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Dietary carrot consumption and the risk of prostate cancer
Abstract
Previous studies regarding the association between carrot intake and prostate cancer risk have reported inconsistent results. We conducted a meta-analysis to summarize evidence on this association and to quantify the potential dose-response relationship.
A systematic literature search of papers published in August 2013 was conducted using PubMed, EMBASE, Scopus, Web of Science, the Cochrane register, and the Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles were screened. The summary risk estimates with 95 % confidence intervals (CIs) for the highest versus the lowest intake of carrots were calculated. A dose-response meta-analysis was also conducted for the studies reporting categorical risk estimates for a series of exposure levels.
We found a significantly decreased risk of prostate cancer associated with the intake of carrots (odds ratio 0.82, 95 % CI 0.70-0.97). In addition, the dose-response meta-analysis indicated that for each serving per week, or 10 g per day increment of carrot intake, the risk estimate of prostate cancer was 0.95 (0.90-0.99) or 0.96 (0.94-0.99). There was no evidence of significant publication bias based on Begg's funnel plot (P = 1.000) or Egger's test (P = 0.804).
Carrot intake might be inversely associated with prostate cancer risk. Because of the limited number of cohort studies and substantial heterogeneity observed between studies in this meta-analysis, further well-designed prospective studies are warranted to confirm the findings from our study.
... They are present not only in fruits and vegetables but also in fungi, bacteria, and algae. They are traditionally classified into two large structural groups: the carotenes, which are mostly hydrocarbons C40 H56 (α-and βcarotene and lycopene), and the xanthophylls, C40 H56(OH)2, which have different oxygenating functions in the molecule (lutein, zeaxanthin, βcryptoxanthin and canthaxanthin) [13]. Carotenoids impart color to foods and some occur only in specific plants, such as lycopene for the tomato, papaya, pink grapefruit, pink guava, and watermelon. ...
... It has substantial anti-oxidative activity. Epidemiological evidences have indicated inverse relationship between lycopene consumption and human prostate cancer [13,17]. Lycopene exhibits anti-cancer activity by inhibiting nuclear transcription factor (NF-κB) and arresting cell growth in the prostate, breast, and endometrial cancer cells [18]. ...
Cancer is a chronic disorder characterized by the uncontrolled growth of cells resulting in the formation of a lump of benign tumors or leading to metastasis in malignant forms of cancer. This review outlines the general aspects of cancer, epidemiology, and types of cancer, and emphasizes the use of functional foods in the treatment of cancer. It highlights the importance of various foods used in daily life and against cancer and other chronic diseases as well. Recent studies have investigated foods including bitter gourd, fish oil, soursoup, curcumin, green tea, red grapes, papaya, beet root, turmeric, Indian Safron, etc. on cancer patients and their potential in relieving pain resulting from chemotherapy or radiotherapy. The mechanism of action of various functional foods and their bioactive components against malignant cancerous cells, especially for carotenoids, flavonoids, and different fatty acids, along with their anti-carcinogenic activity, have been indicated in detail. This chapter not only emphasizes the dire need of exploring safe functional foods against cancer, but also provides future insights into the addition of active food components in cancer therapeutics.
... Although the consumption of carrots in our study was low compared with others [42], we found a strong dose-responsive inverse association with prostate cancer. Consistent with this finding, a recent meta-analysis including 10 studies (eight case-control and two cohort) showed around 20% significantly lower risk of prostate cancer in the category with the highest level of carrot consumption relative to the one with the lowest level [43]. Because of the scarcity of studies on dietary carrots and prostate cancer risk in Asia [43], our study adds to the evidence for a potentially beneficial role of carrot in prostate cancer prevention among populations, even with a relatively low consumption. ...
... Consistent with this finding, a recent meta-analysis including 10 studies (eight case-control and two cohort) showed around 20% significantly lower risk of prostate cancer in the category with the highest level of carrot consumption relative to the one with the lowest level [43]. Because of the scarcity of studies on dietary carrots and prostate cancer risk in Asia [43], our study adds to the evidence for a potentially beneficial role of carrot in prostate cancer prevention among populations, even with a relatively low consumption. ...
The incidence of prostate cancer has increased in Vietnam, but there have been few studies of the risk factors associated with this change. This retrospective case-control study investigated the relation of the intake of carotenoids and their food sources to prostate cancer risk. A sample of 652 participants (244 incident prostate cancer patients, aged 64–75 years, and 408 age frequency-matched controls) were recruited in Ho Chi Minh City during 2013–2015. The habitual diet was ascertained with a validated food-frequency questionnaire, and other factors including demographic and lifestyle characteristics were assessed via face-to-face interviews by trained nurses. Multivariate-adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression models. The risk of prostate cancer decreased with increasing intakes of lycopene, tomatoes, and carrots; the respective ORs (95% CIs) were 0.46 (0.27, 0.77), 0.39 (0.23, 0.66), and 0.35 (0.21, 0.58), when comparing the highest with the lowest tertile of intake (p for trend < 0.01). No statistically significant associations were found for the intake of α-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin, and major food sources of carotenoids. In conclusion, Vietnamese men with a higher intake of lycopene, tomatoes, and carrots may have a lower risk of prostate cancer. However, large prospective studies are needed in this population to confirm this finding.
... In epidemiological studies, such as case-control and prospective cohort studies, the potential relationship between carrot consumption and site-specific cancer incidence has been investigated. A dose-response metaanalysis indicated that carrot intake might be associated with a reduced risk of prostate cancer [6]. Fallahzadeh et al. reported an inverse relationship between the consumption of carrot and gastric cancer risk [7]. ...
... In conclusion, this meta-analysis indicates that high intake of carrot is associated with a low incidence of urothelial cancer. Moderate consumption of carrot has been recommended by many researchers, as carrot intake has been reported to be associated a low incidence of several cancers [6,7] and protection of vision [19] and cardiovascular system [20,21]. However, because of the above discussed limitations, further large well-designed prospective cohort studies are warranted to confirm the findings from this meta-analysis. ...
Previous studies regarding the relationship between carrot intake and risk of urothelial cancer have reported conflicting results. Hence we performed a meta-analysis of eligible studies to summarize evidence on this association. A comprehensive search up to January 2017 was performed in PubMed, Web of Science, Scopus, EMBASE, Cochrane register, and Chinese National Knowledge Infrastructure (CNKI) databases. The combined odds ratio (OR) with 95% confidence interval (CI) for the highest versus the lowest intake of carrot was calculated. A total of six epidemiological studies consisting of four case-control and two cohort studies were included. Overall analysis indicated a significantly reduced risk of urothelial cancer for high intake of carrot (OR = 0.63, 95% CI 0.44–0.90). Obvious significant heterogeneity was observed among included studies (P < 0.001 for heterogeneity; I² = 79.6%). There was no significant publication bias by Begg's test (P = 0.348) or Egger's test (P = 0.130). In conclusion, this meta-analysis indicates that high intake of carrot is associated with a low incidence of urothelial cancer. Considering the limited included studies and huge heterogeneity, further large well-designed prospective cohort studies are warranted to confirm the findings from our meta-analysis.
... 3=Central Asiatic Center: for core region of the Asian continent includes Northwest India (Punjab and Kashmir), Afghanistan, Tajikistan, Uzbekistan and western Tian-Shan. Central Asia is not only located on the Silk Road and a corridor for human migrations (Lacau et al., 2012), but also center of origin for 43 species in Crop (Vavilov, 1951;Ladizinsky,1998;Wikipedia, 2013), some functional foods with anticancer including to grape, mung bean, spinach, carrot, onion, garlic, mustard, apple, flax, and sesame (Lowcock et al., 2013;Maeda et al., 2013;Zeng et al., 2013;Cheah et al., 2014;Prado-Silva et al., 2014;Xu et al., 2014); Up to now, Central Asia is major production region for these functional crop. Grape seed procyanidins not only enhanced the impact of 5-Fluorouracil in killing colon cancer cells, but also surpassed standard 5-Fluorouracil chemotherapy as an anticancer agent (Cheah et al., 2014). ...
... Mono-galactosyl diacylglycerol from spinach suppressed the proliferation of colon cancer cells, which has the potential for cancer prevention and health promotion (Maeda et al., 2013). Carrot intake might be inversely associated with prostate cancer risk (Xu et al., 2014). Compounds in onions have been reported with lots of health benefits, including anticancer, antiplatelet, antithrombotic, anti-asthmatic, and antibiotic effects (Suleria et al., 2015). ...
Cancer is the leading cause of death around the world. Anticancer activities from many functional food sources have been reported in years, but correlation between cancer prevalence and types of food with anticancer activities from crop origin center in the world as well as food source with human migration are unclear. Hunger from food shortage is the cause of early human evolution from Africa to Asia and later into Eurasia. The richest functional foods are found in crop origin centers, housing about 70% in the world populations. Crop origin centers have lower cancer incidence and mortality in the world, especially Central Asia, Middle East, Southwest China, India and Ethiopia. Asia and Africa with the richest anticancer crops is not only the most important evolution base of humans and origin center of anticancer functional crop, but also is the lowest mortality and incidence of cancers in the world. Cancer prevention of early human migrations was associated with functional foods from crop origin centers, especially Asia with four centers and one subcenter of crop origin, accounting for 58% of the world population. These results reveal that coevolution between human's anticancer activities associated with functional foods for crop origin centers, especially in Asia and Africa.
... Carrot (Daucus carota L.), one of the top ten vegetable crops in the world, is a rich source of natural antioxidants, including carotenoids, anthocyanins, vitamins, etc. [18]. Carrots are favored by consumers due to their high nutritional and medicinal value [19,20]. As the demand for carrots increases, improving the yield and quality of carrots is an urgent problem that needs to be solved in carrot production. ...
Background
Carrot ( Daucus carota L.), an important root vegetable, is very popular among consumers as its taproot is rich in various nutrients. Abiotic stresses, such as drought, salt, and low temperature, are the main factors that restrict the growth and development of carrots. Non-heme carotene hydroxylase (BCH) is a key regulatory enzyme in the β-branch of the carotenoid biosynthesis pathway, upstream of the abscisic acid (ABA) synthesis pathway.
Results
In this study, we characterized a carrot BCH encoding gene, DcBCH1 . The expression of DcBCH1 was induced by drought treatment. The overexpression of DcBCH1 in Arabidopsis thaliana resulted in enhanced tolerance to drought, as demonstrated by higher antioxidant capacity and lower malondialdehyde content after drought treatment. Under drought stress, the endogenous ABA level in transgenic A. thaliana was higher than that in wild-type (WT) plants. Additionally, the contents of lutein and β-carotene in transgenic A. thaliana were lower than those in WT, whereas the expression levels of most endogenous carotenogenic genes were significantly increased after drought treatment.
Conclusions
DcBCH1 can increase the antioxidant capacity and promote endogenous ABA levels of plants by regulating the synthesis rate of carotenoids, thereby regulating the drought resistance of plants. These results will help to provide potential candidate genes for plant drought tolerance breeding.
... Dietary habits, including nutrients and dietary patterns, potentially affect prostate cancer pathogenesis and progression through various mechanisms mediated inflammation, antioxidant effects, and the action of sex hormones (3). Several dietary factors (4,5) have been identified to be associated with the risk of prostate cancer, although controversial results have been reported for almost all nutrients. ...
Objective: Several epidemiological studies have linked tomato products consumption with prostate cancer risk; however, the findings yielded inconsistent results. The aim of the present meta-analysis is to summary the evidence on this association based on eligible cohort studies.
Materials and Methods: A comprehensive literature search of articles was performed in March 2021 using PubMed, ISI Web of Science, and Scopus databases. A random-effects model was used to calculate the combined relative risks (RRs) and their corresponding 95% confidence intervals (CIs). Heterogeneity across studies was assessed using Cochran's Q statistic and the I² score.
Results: A total of 10 prospective studies were finally included in our meta-analysis. There was no evidence of a significant association between tomato products consumption and prostate cancer risk (RR 0.91, 95% CI 0.79–1.03, P = 0.138). Subgroup meta-analyses were performed by tomato types, geographical region, publication year, study quality and number of cases. No significant associations were observed in any subgroups (all P > 0.05). No significant publication bias was observed using Begg's test (P = 0.602) or Egger's test (P = 0.957).
Conclusion: The results of this meta-analysis indicated that tomato consumption was not related with the risk of prostate cancer. Further prospective large-scale cohort studies are still warranted to verify our findings.
... Several studies have also found stronger negative correlations of developing cancer and in particular lung cancer with intake of α-carotene rather than β-carotene [13,14]. Thus, it is widely accepted that carrots play a central role as a protecting vegetable against development of cancer, which is supported by recent meta-analysis studies on carrot consumption in relation to the development of breast, gastric, lung and prostate cancer [15][16][17][18]. The cancer-preventive effect of this vegetable has mainly been explained by its high contents of carotenoids; however, intervention studies have shown that supplementation with carotenoids does not protect against development of this disease [10,11,19]. ...
Carrots are consumed worldwide. Several meta-analysis studies on carrot consumption have indicated that carrots play a central role as a protecting vegetable against development of different types of cancers. A cancer-preventive role of carrots is plausible because they are the main dietary source of the bioactive polyacetylenic oxylipins falcarinol (FaOH) and falcarindiol (FaDOH), which have shown anti-proliferative and anti-inflammatory activity in numerous in vitro studies. In addition, purified FaOH and FaDOH have, in recent studies in colorectal cancer (CRC)-primed rats, demonstrated an anti-neoplastic effect in a dose-dependent manner. The mechanisms of action for this effect appears to be due to inhibition of pro-inflammatory and transcription factor biomarkers for inflammation and cancer. However, studies of the CRC-preventive effect of carrots in a large cohort are still missing. We therefore examined the risk of being diagnosed with CRC as predicted by intake of carrots in a Danish population of 57,053 individuals with a long follow-up. Self-reported intake of raw carrots at a baseline of 2-4 carrots or more each week (>32 g/day) was associated with a 17% decrease in risk of CRC with a mean follow-up of >18 years, compared to individuals with no intake of raw carrots even after extensive model adjustments (HR 0.83 CI 95% 0.71; 0.98). An intake below 2-4 carrots each week (<32 g/day) was not significantly associated with reduced risk of CRC (HR 0.93 CI 95% 0.82; 1.06). The results of this prospective cohort study clearly support the results from studies in cancer-primed rats for CRC and hence a CRC-preventive effect of carrots.
... contain alpha-and beta-carotene [114], and extracts may have (phyto)estrogenic activity [115,116] or be associated with estrogen metabolism [117]. While the mechanism(s) remain(s) unknown, epidemiological studies suggest that dietary carrot intake is associated with lower rates of breast [118,119] and prostate cancer [120]. While these are preliminary findings, it would seem that, based on their carotenoid (especially beta-carotene) content, there could be an implied association with ovarian health based on the animal studies listed above, perhaps related to the concentration of carotenoids in the ovary. ...
Over the past decades, thousands of published studies have amassed supporting recommendations to consume fruits and vegetables for physiological and psychological health. Newer research has emerged to suggest that these plant-based foods contain a plethora of not only vitamins and minerals, but perhaps, most importantly, phytonutrients. These phytonutrients have known pleiotropic effects on cellular structure and function, ultimately resulting in the modulation of protein kinases and subsequent epigenetic modification in a manner that leads to improved outcomes. Even though eating fruits and vegetables is a well-known feature of a healthy dietary pattern, population intakes continue to be below federal recommendations. To encourage consumers to include fruits and vegetables into their diet, an “eat by color” approach is proposed in this review. Although each individual food may have numerous effects based on its constituents, the goal of this simplified approach was to identify general patterns of benefits based on the preponderance of scientific data and known mechanisms of food-based constituents. It is suggested that such a consumer-oriented categorization of these plant-based foods may lead to greater recognition of their importance in the daily diet throughout the lifespan. Other adjunctive strategies to heighten awareness of fruits and vegetables are discussed.
... [2] Physical activities, coffee consumption, statin use, intake of certain vegetables also have been linked with the prevention of prostate cancer. [3][4][5][6][7] Recently, it was proposed that metformin had additional beneficial anticarcinogenic effects in human cancers, [8,9] including prostate cancer. [10] Metformin, a biguanide, is the most widely prescribed antidiabetic drug worldwide due to its clinical effectiveness and tolerability. ...
Background:
The relationship between metformin use and the risk of prostate cancer is still inconclusive. Therefore, we performed a systematic review and meta-analysis of all eligible cohort studies to evaluate a potential association of metformin use with prostate cancer risk.
Methods:
A comprehensive literature search was performed in PubMed and Web of Science databases through July 2018. A DerSimonian and Laird random-effects model was applied to calculate the pooled relative risk (RR) and its 95% confidence interval (CI).
Results:
Eighteen cohort or nested case-control studies were included in this study with a total of 52,328 cases. In a random-effect pooled analysis, metformin use was not significantly associated with the risk of prostate cancer (RR 0.97, 95% CI 0.80-1.16, P = .711). Statistically significant heterogeneity was identified among included studies (P < .001, I = 98.1%). Sensitivity analysis indicated that no single study dominated the pooled RR.
Conclusion:
The present large meta-analysis of cohort studies did not find an association between metformin use and prostate cancer risk.
... [3] Additional but less established risk factors include physical activity, body mass index, and some dietary factors. [4][5][6][7] Emerging studies have indicated that the coagulation cascade and thrombocytes implicated in the development and progression of cancer, and that anticoagulant drugs could in theory improve prognosis. [8,9] For instance, activated platelets release secretory factors, such as proangiogenic regulatory proteins, chemokines, and microparticles within the microenvironment, to promote tumor growth and metastasis. ...
Background:
Vitamin K antagonists (VKAs) may have potential antitumor effects in prostate cancer. However, the findings of observational studies are inconsistent. The purpose of the present study was to estimate the quantitative association between VKAs use and prostate cancer risk by combining the results of all eligible observational studies.
Methods:
PubMed and Web of Science database were searched from inception until May, 2018. A DerSimonian random-effects model was used to combine the studies. Study heterogeneity was measured using the chi-squared and I statistics.
Results:
Six eligible studies were eventually included in our meta-analysis. There was an inverse but not statistically significant association between ever use of VKAs and the risk of prostate cancer (relative risk [RR] 0.84, 95% confidence interval [CI] 0.70-1.01, P = .063) with large heterogeneity across studies (P < .001 for heterogeneity, I = 94.6%). When analysis restricted to long term of VKAs user (>3 years), the pooled risk estimate was 0.83 (0.77-0.90) without obvious heterogeneity (P = .597, I = 0.0%).
Conclusion:
This meta-analysis indicates that VKAs use may be associated with a decreased risk of prostate cancer, especially in long-term users.
... [3] Evidence from meta-analysis also showed reduced risk of prostate and gastric cancers in the high carrot intake population. [4,5] Epidemiological studies have investigated the possible relationship between carrot intake and breast cancer risk. However, the results were not completely consistent, with some studies having found significant inverse association, [6,7] while others have not. ...
Background:
We aimed to estimate the association between dietary carrot intake and risk of breast cancer by conducting a meta-analysis of epidemiologic studies.
Methods:
Relevant studies were identified by searching databases through September 2017. We included studies that reported risk estimates with 95% confidence intervals for the association between dietary carrot intake and breast cancer risk. Random-effects models were used to calculate the summary risk estimates. Publication bias was estimated using Begg's funnel plot and Egger's regression asymmetry test.
Results:
A total of 10 articles met the eligibility criteria and were included in the meta-analysis involving 13,747 cases. The combined odds ratios (ORs) of breast cancer for the highest compared with the lowest dietary carrot intake was 0.79 (95% CI: 0.68, 0.90), and a significant heterogeneity was observed. In the subgroup analyses separated by study design, the inverse associations were more pronounced in the case-control studies than in the cohort studies, while the associations did not significantly differ by geographical region, study quality, exposure assessment. Omission of any single study had little effect on the combined risk estimate.
Conclusion:
The overall current literatures suggested that dietary carrot intake was associated with decreased risk of breast cancer.
... Processed carrot foods are among the basic meals for infants and young children (Seidel et al., 2015). Consumption of carrot is also linked to decreased risk of prostate cancer and has the potential to improve heart and liver functionality and consequently protect against cardiovascular diseases (Xu et al., 2014;Potter, Foroudi, Stamatikos, Patil, & Deyhim, 2011;Nicolle et al., 2003). The production of α-tocopherol-β-carotene (ATBC) drinks, also called carotenoid drinks, depends on carrot juice as a natural source of provitamin A (Simon et al., 2008;Demir, Acar, & Bahç eci, 2004). ...
Carrot has a relatively high content of Vitamin C and it is a major source of natural carotenoids. However, carrot has a short shelf-life and is better consumed fresh. A quick assessment of its quality attributes is important to preserving its freshness. The objective of this study was to apply Vis-NIR spectroscopy to noninvasively assess and predict the various quality attributes of carrot (cv. Nectar), namely color (L*a*b*), moisture content (MC), total soluble solids (TSS), firmness, Vitamin C, and β-carotene. Two spectroscopic sensors (400-1,000 nm and 900-1,700 nm) were utilized and samples included whole root and 25.4 mm thick sliced disc. The best prediction models using partial least squares regression yielded correlation coefficient, r, and ratio of performance to deviation or r(RPD) of 0.50(0.73), 0.84(0.88), 0.86(2.07), 0.69(0.66), 0.97(1.44), 0.90(1.49), 0.47(1.47), and 0.92(1.76) for color indices, L* a* b*, firmness, MC, TSS, Vitamin C, and β-carotene, respectively. However, using only the wavelengths selected by interval partial least squares, the r(RPD) values for the aforementioned attributes improved and are presented as follows: 0.92(1.97), 0.96(2.83), 0.98(5.85), 0.99(6.65), 0.98(3.91), 0.99(5.93), 0.98(4.16), and 0.98(4.43), respectively. Generally, Vis-NIR region had higher prediction performance than NIR region, and whole roots had similar prediction performance as sliced samples. This study shows that rapid determination of quality parameters of carrot is possible through non-destructive Vis-NIR sensing, which could be useful for quality tracking during carrot supply chain. Moreover, results of this study could be improved using a larger sample size.
... Meanwhile, the factors causing heterogeneity were also explored using the residual maximum likelihood based random-effects meta-regression analysis. 27 All the statistical analyses were performed using Stata V.12.0 software (StataCorp, College Station, Texas, USA), and two-sided test was used to evaluate the p value. ...
Objectives
The aim of this study was to explore the prognostic value of ki67 as a marker in patients with non-muscle invasive bladder cancer (NMIBC) treated with BCG.
Methods
Studies were systematically retrieved from the relevant databases (Web of Science, PubMed, Cochrane Library and Embase), and the expiry date was May 2017. The research steps referred to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement.
Results
A total of 11 studies that complied with the inclusion criteria were included. The expression of ki67 was not statistically significantly associated with recurrence-free survival (RFS) (HR 1.331; 95% CI 0.980 to 1.809). No significant heterogeneity was found among all included studies (I²=36.7%, p=0.148). The expression of ki67 was statistically significantly associated with progression-free survival (PFS) (HR 2.567; 95% CI 1.562 to 4.219), and the overexpression of ki67 was the risk factor for PFS. Significant heterogeneity was noted among all the included studies (I²=55.6%, p=0.021). The studies that might cause heterogeneity were excluded using the Galbraith plot, and then the meta-analysis was performed again. The results showed that the expression of ki67 was still associated with PFS (HR 2.922; 95% CI 2.002 to 4.266).
Conclusions
The overexpression of ki67 was the risk factor for PFS, and the relationship between the expression of ki67 and RFS was not statistically significant in patients with NMIBC treated with BCG intravesical immunotherapy. Well-designed, prospective, with a large sample size are still needed to validate the findings.
... Advancing age, ethnicity and family history of prostate cancer are the only well-established risk factors (3,4). Other factors, such as physical activity, body mass index (BMI) (5), hormones and diet (6,7), are also thought to be associated with the risk of prostate cancer (8,9). It has been proposed that the risk associated with shift work could be explained by decreased exposure to daylight, increased the levels of sex hormones or suppression of melatonin, which might stimulate the growth of prostate cancer cell (10)(11)(12). ...
Observational studies suggest that shift work may be associated with prostate cancer. However, the results are inconsistent. The objective of this study is to quantitatively assess the association between shift work and the risk of prostate cancer. Relevant studies were identified by a comprehensive search of the PubMed, Embase, Web of Science, and China National Knowledge Infrastructure databases to September 2017. We also reviewed the reference lists from retrieved articles. Observational studies that reported relative risk (RR) with 95% confidence intervals (CIs) for the association between shift work and the risk of prostate cancer were included. A linear and nonlinear dose-response meta-analysis was performed. Fifteen studies with 16 independent reports involving 2,546,822 individuals and 10,715 patients with prostate cancer were included. The pooled adjusted RR for the association between ever exposure to shift work and prostate cancer risk was 1.23 (95% CI, 1.08-1.41; P<0.001). A nonlinear association of prostate cancer risk with duration of shift work was identified (P for nonlinearity=0.001). Subgroup analysis demonstrated that a higher pooled RR of prostate cancer for studies among Asian populations (RR=1.98, 95% CI, 1.34-2.93; P=0.618). A positive association was observed in rotating shift groups (RR=1.10, 95% CI, 1.00-1.26; P=0.156), but not in other shift groups. Integrated evidence from this meta-analysis suggests that shift work is significantly associated with an increased risk of prostate cancer, and a nonlinear association between duration of shift work and prostate cancer was found.
... O'Neill et al. (2001) stated that carrot is the most vegetable crop contributing to β-carotene nutrient in several European countries including UK, Republic of Ireland, Spain, France, and The Netherlands in the 2001 winter. Xu et al. (2014) found that there was a significant decrease in the prostate cancer risk associated with regular consumption of carrot. Moreover, the effect of uniform intake of carrot on cholesterol absorption in rats was investigated by Nicole et al., (2003). ...
Carrot is a root crop that has relatively high content of vitamin C and carotenoids. Carrot is usually consumed fresh, juiced or cooked. It is also a major source of industrial natural carotenoids, a precursor to vitamin A. Rapid determination of quality parameters indeed helps process engineers and storage managers to track the condition of root crops such as carrots during storage and/or before processing. The objectives of this study were to apply VIS-NIR spectroscopy to noninvasively assess and predict the various quality attributes of carrot (cv. Nectar) including color parameters (L*a*b*), moisture content (MC), total soluble solids (TSS), firmness, vitamin C content, and β-carotene. Two spectroscopic sensors with different range were used (400-1000 nm and 900-1700 nm). Samples included whole roots and sliced discs. The best prediction models using partial least squares regression (PLSR) yielded correlation coefficient, r and ratio of performance to deviation or r(RPD) with values of 0.92 (2.46), 0.85(1.65), 0.94(2.85), 0.96(3.55), 1.00(17.92), 0.90(2.16), 0.98(4.73), and 0.97(3.88) for L*, a*, b*, firmness, MC, TSS, vitamin C, and β-carotene, respectively. Generally, whole roots and VIS-NIR sensor have high prediction (r = 0.69 – 1.00). Results obtained in this research could be enhanced with more samples to develop a better and higher accuracy predictive multispectral model for carrot quality prediction with possible extension to other similar vegetables in post-harvest losses reduction.
... Age, race/ethnicity, and family history of prostate cancer are the most established risk factors for prostate cancer [2]. Several modifiable factors, such as physical activity [3] and intake of specified vegetables (e.g., carrots [4] and cruciferous vegetables [5]), also have been reported to be associated with prostate cancer incidence, although controversies still persist. ...
Previous studies regarding the relationship between legume intake and risk of prostate cancer have reported inconsistent results. We conducted a meta-analysis of prospective cohort studies to summarize evidence on this association. A systematic literature search of articles published through June 2016 was performed using PubMed and Web of Science databases. The combined relative risk (RR) with its 95% confidence interval (CI) for the highest versus the lowest intake of legumes was calculated with a random-effects model. Dose-response meta-analysis was also performed for the studies that provided at least three levels of legume consumption. Ten articles (eight cohorts) reporting 281,034 individuals and 10,234 incident cases were identified. The individuals with high consumption of legumes compared with the reference group experienced a significantly reduced risk for developing prostate cancer (RR: 0.85 [95% CI 0.75-0.96], P = 0.010). Moderate heterogeneity of RRs was observed across these studies (P = 0.064 for heterogeneity, I2 = 45.8 %). Dose-response meta-analysis indicated that the risk of prostate cancer reduced by 3.7% (95% CI 1.5%-5.8%) for each 20 grams per day increment of legume intake. In conclusion, the results from this meta-analysis suggest that a high intake of legumes is associated with a low incidence of prostate cancer.
... Several epidemiological studies have explored the association of dietary habits on PC risk, and meta-analysis has recently summarized the association of individual foods and nutrients with PC risk. Indeed, significant preventive effects have been found for the intake of allium vegetables [4], carrots and coffee [5,6]; whereas, inconsistent correlation has been observed between PC risk and the consumption of tomatoes and lycopene [7,8], tea [9], fruits and vegetables [10], fiber [11], fat [12], red meat, processed meat, and seafood [13]. On the other hand, dairy products, calcium, and eggs seem to act as risk factors for PC [13,14]. ...
Dietary patterns were recently applied to examine the relationship between eating habits and prostate cancer (PC) risk. While the associations between PC risk with the glycemic index and Mediterranean score have been reviewed, no meta-analysis is currently available on dietary patterns defined by “a posteriori” methods. A literature search was carried out (PubMed, Web of Science) to identify studies reporting the relationship between dietary patterns and PC risk. Relevant dietary patterns were selected and the risks estimated were calculated by a random-effect model. Multivariable-adjusted odds ratios (ORs), for a first-percentile increase in dietary pattern score, were combined by a dose-response meta-analysis. Twelve observational studies were included in the meta-analysis which identified a “Healthy pattern” and a “Western pattern”. The Healthy pattern was not related to PC risk (OR = 0.96; 95% confidence interval (CI): 0.88–1.04) while the Western pattern significantly increased it (OR = 1.34; 95% CI: 1.08–1.65). In addition, the “Carbohydrate pattern”, which was analyzed in four articles, was positively associated with a higher PC risk (OR = 1.64; 95% CI: 1.35–2.00). A significant linear trend between the Western (p = 0.011) pattern, the Carbohydrate (p = 0.005) pattern, and the increment of PC risk was observed. The small number of studies included in the meta-analysis suggests that further investigation is necessary to support these findings.
... The most well-established risk factors for prostate cancer are age, positive family history, and race/ ethnicity [2]. Less well-established but modifiable risk factors include unhealthy behaviors (e.g., lack of physical activity [3]) and eating fewer vegetables, such as carrots [4] and cruciferous vegetables [5]. In addition, it has been proposed that statins [6], aspirin [7], and metformin [8] have additional beneficial anti-carcinogenic effects and are linked to a lower risk of prostate cancer, although the evidence has been conflicting. ...
Emerging evidence suggests that renin-angiotensin system (RAS) may act as a molecular and therapeutic target for treating site-specific cancers, including prostate cancer. However, previous observational studies regarding the association between RAS inhibitors and prostate cancer risk have reported inconsistent results. We examined this association by performing a systematic review and meta-analysis. A total of 20,267 patients from nine cohort studies were enrolled. Compared with non-users of RAS inhibitors, individuals using RAS inhibitors had a reduced risk of prostate cancer (RR 0.92, 95 % CI 0.87-0.98), without statistically significant heterogeneity among studies (P = 0.118 for heterogeneity, I2 = 37.6 %). In addition, when subgroup analyses by study quality and number of cases, more statistically significant associations were observed in studies of high quality (RR 0.93, 95 % CI 0.88-0.97) and large sample size (RR 0.94, 95 % CI 0.91-0.98). There was no evidence of significant publication bias with Begg's test (P = 0.602) or with Egger's test (P = 0.350). Overall, this study indicates that use of RAS inhibitors may be associated with a decreased risk of prostate cancer. Large-scale well designed studies are needed to further explore this association.
... For example, certain vegetables, such as soy and carrot, have been linked to the reduction of prostate cancer risk. 3,4 There is also some evidence that firefighters may have an increased risk of prostate cancer. 5,6 In addition to the exposure to toxic combustion products, firefighters' shift work schedule may partly explain this association. ...
Background
Night-shift work is suggested to be associated with an increased risk of breast cancer, but its association with prostate cancer is still controversial. We examined this association by conducting a systematic review and meta-analysis.
Methods
Studies were identified by searching PubMed, EMBASE, Ovid, Web of Science, the Cochrane register, and the China National Knowledge Infrastructure databases through December 25, 2014. Summary relative risks (SRRs) with their corresponding 95% confidence intervals (CIs) were calculated using a random effects or fixed effects model. Heterogeneity and publication bias were also evaluated.
Results
A total of 2,459,845 individuals from eight published studies were included in this meta-analysis. Analysis of all studies suggested that night-shift work was associated with a significantly increased risk of prostate cancer (RR: 1.24, 95% CI: 1.05–1.46; P=0.011). Sensitivity analysis showed that the association remained significant when repeating the analysis after removing one study each time. Dose–response meta-analysis suggested that an increase in night-shift work of 5 years duration was statistically significantly associated with a 2.8% (95% CI: 0.3, 5.4%, P=0.030) increase in the risk of prostate cancer. There was no significant publication bias.
Conclusion
Based on a meta-analysis, night-shift work is associated with an increased risk of prostate cancer. Because of the limited number of included studies and the large level of heterogeneity, further well-designed studies are still warranted to confirm the findings of our analysis.
... 34 Another recent meta-analysis of cohort studies has indicated that high intakes of dairy products and dairy calcium may increase total prostate cancer risk. 35 Conversely, consumption of dietary carrot 36 and cruciferous vegetables 37 might be inversely associated with prostate cancer risk. ...
Background
The relationships between dietary fiber, whole grains, carbohydrate, glycemic index (GI), glycemic load (GL), and prostate cancer risk are unclear. We conducted a systematic review and meta-analysis to investigate these associations.
Methods
Relevant studies were identified by a search of PubMed database and EMBASE database up to April 2015. A random effects model was used to calculate the summary relative risks (RRs) and their corresponding 95% confidence intervals (CIs).
Results
Twenty-seven epidemiological studies (18 case–control studies and nine cohort studies) were included in the final analysis. The pooled RRs of prostate cancer were 0.94 (95% CI 0.85–1.05, P=0.285), 1.13 (95% CI 0.98–1.30, P=0.095), 0.96 (95% CI 0.81–1.14, P=0.672), 1.06 (95% CI 0.96–1.18, P=0.254), and 1.04 (95% CI 0.91–1.18, P=0.590) for dietary fiber, whole grains, carbohydrate, GI, and GL, respectively. There was no evidence of significant publication bias based on the Begg’s test and Egger’s test.
Conclusion
The findings of this meta-analysis indicate that, based on available information, dietary fiber, whole grains, carbohydrate, GI, and GL are not associated with the risk of prostate cancer.
... In addition, the Galbraith plot was used to detect the possible sources of heterogeneity [25], and a re-analysis was conducted after excluding the studies that possibly contributed to the heterogeneity. Additionally, residual maximum likelihood (REML)-based random-effects meta-regression analysis was used to explore the potential sources of heterogeneity [26,27]. ...
Published studies have yielded inconsistent results on the relationship between p53 status and the prognosis of non-muscle invasive bladder cancer (NMIBC) treated with Bacillus Calmette-Guérin (BCG) intravesical therapy. Therefore, we performed a meta-analysis to evaluate the prognostic value of p53 in NMIBC treated with BCG.
We systematically searched for relevant literature in PubMed, EMBASE, CNKI, and Chinese Wanfang databases. Hazard ratios (HRs) with 95% confidence intervals (CIs) were combined as the effect size (ES) across studies for recurrence-free survival (RFS) and progression-free survival (PFS).
A total of 11 studies, consisting of 1,049 participants, met the criteria. Overall, there was no clear relationship between p53 status and RFS or PFS for NMIBC patients treated with BCG (HR: 1.40, 95% CI: 0.91-2.16; HR: 1.37, 95% CI: 0.90-2.09, respectively). Obvious heterogeneity was observed across the studies (I2 = 69.5%, P = 0.001; I2 = 44.7%, P = 0.081, respectively). In stratified analysis by region, p53 overexpression was a predictor of poor RFS in Asian populations (HR: 1.57, 95% CI: 1.08-2.27). In addition, after excluding the studies that possibly contributed to the heterogeneity by the Galbraith plot, the overall association for RFS became statistically significant (HR: 1.38 95% CI: 1.08-1.77) without evidence of heterogeneity (I2 = 0.0%, P = 0.499).
This meta-analysis suggests that p53 overexpression in NMIBC patients treated with BCG may be associated with RFS, especially in Asian populations. Because of the heterogeneity and other limitations, further studies with rigid criteria and large populations are still warranted to confirm our findings.
... The following data were extracted from each study and included in the final analysis: the study name (together with the first author's name and year of publication), country of origin, gender, age, study design, source of patients, number of cases/controls, risk factor assessment, matching covariates, and adjusted covariates. We contacted the corresponding authors of the primary studies to acquire missing or insufficient data (when necessary), used group consensus and consulted a third reviewer to resolve discrepancies, and assigned scores of ,7 and $ 7 for low-and high-quality studies, respectively, on the nine-score Newcastle-Ottawa Scale (NOS) [19,20]. ...
Objective
Pesticide exposure has been linked to increased risk of cancer at several sites, but its association with risk of myelodysplastic syndromes (MDS) is still unclear. A meta-analysis of studies published through April, 2014 was performed to investigate the association of pesticide exposure with the risk of MDS.
Methods
Studies were identified by searching the Web of Science, Cochrane Library and PubMed databases. Summary odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated using random- or fixed-effect models.
Results
This meta-analysis included 11 case-control studies, all of which demonstrated a correlation between pesticide exposure and a statistically significant increased risk of MDS (OR = 1.95, 95% CI 1.23–3.09). In subgroup analyses, patients with pesticide exposure had increased risk of developing MDS if they were living in the Europe or Asia and had refractory anemia (RA) or RA with ringed sideroblasts (RARS). Moreover, in the analysis by specific pesticides, increased risk was associated with exposure to insecticides (OR = 1.71, 95% CI 1.22–2.40) but not exposure to herbicides or fungicides.
Conclusion
This meta-analysis supports the hypothesis that exposure to pesticides increases the risk of developing MDS. Further prospective cohort studies are warranted to verify the association and guide clinical practice in MDS prevention.
The study aimed to measure the carotenoid (Car) and pH contents of carrots using hyperspectral imaging. A total of 300 images were collected using a hyperspectral imaging system, covering 472 wavebands from 400 to 1000 nm. Regions of interest (ROIs) were defined to extract average spectra from the hyperspectral images (HIS). We developed two models: least squares support vector machine (LS-SVM) and partial least squares regression (PLSR) to establish a quantitative analysis between the pigment amounts and spectra. The spectra and pigment contents were predicted and correlated using these models. The selection of EWs for modeling was done using the Successive Projections Algorithm (SPA), regression coefficients (RC) from PLSR models, and LS-SVM. The results demonstrated that hyperspectral imaging could effectively evaluate the internal attributes of carrot cortex and xylem. Moreover, these models accurately predicted the Car and pH contents of the carrot parts. This study provides a valuable approach for variable selection and modeling in hyperspectral imaging studies of carrots.
Carrots are main dietary sources of several potential anti-cancer compounds, including polyacetylenes, while β-carotene has shown no benefits in controlled cancer trials. Accordingly, associations between carrot intake and cancer incidence were quantified, where necessary using α-carotene as a non-causal biomarker of carrot consumption, by searching for studies published before June 2022 reporting risk estimates for relationships of cancer incidence with carrot intake or α-carotene intake or α-carotene plasma concentration, supplemented with hand searches of included studies and reviews. Meta-analyses comparing highest and lowest reported intakes in prospective studies using a random-effects model estimated summary relative risks (RRs) with 95% confidence intervals (CIs), separately for carrot intake or α-carotene plasma concentration, and the corresponding dose-responses. Of 198 observational studies, in 50 prospective studies with 52000 cases recording carrot intake, the cancer-risk was substantially reduced (RR 0.90, 95% CI 0.87–0.94, p ˂ 0·00004). In 30 prospective studies with 9331 cases reporting plasma α-carotene levels, summary RR was 0.80 (0.72–0.89, p ˂ 0·00006). For both exposure types, inter-study heterogeneity was moderate, interaction with cancer types insignificant, and the dose-response significant (p ˂ 0·01). In conclusion, carrot consumption is robustly associated with decreased cancer-risk; carrot consumption should be encouraged, and the causal mechanisms further investigated.
In vitro and animal studies have shown that carrot juice containing bioactive natural products, such as falcarinol (FaOH) and falcarindiol (FaDOH), can affect inflammation. The present study was designed to test whether oral intake of carrot juice containing the bioactive acetylenic oxylipins FaOH and FaDOH affects mediators of acute inflammation or the innate immune response in human blood. Carrot juice (500 mL) was administered orally to healthy volunteers, and blood samples were drawn before and 1 h after juice intake. Next, the blood samples were split in two, and one sample was stimulated ex vivo with lipopolysaccharide (LPS) and incubated at 37 °C for 24 h. The concentrations of 44 inflammatory cytokines and chemokines were examined using multiplex electrochemiluminescence analysis. In blood samples not stimulated with LPS, a significant increase in IL-15 was measured 1 h after carrot juice intake. Cytokines like IFN-ɣ, IL-12/IL-23(p40), IL-23, IL-17A, IL-17B, IL-17D, and IL-22 were significantly increased in LPS-stimulated blood samples after carrot juice intake. The upregulation of the immunostimulating cytokines belonging to the IL-23/IL-17 Th17 axis suggests that carrot juice intake could benefit diseases where inflammation plays a role, like in the early stages of diabetes or cancers.
In recent years, the benefits of carrots and carotene in different areas of health have been examined. The purpose of this umbrella review was to identify the associations between carrots and carotene and multiple health outcomes. The review considered evidence from meta‐analyses of interventional and observational studies of carrots and carotene and any health outcome. We comprehensively searched Web of Science, PubMed, and Embase. For each association, we estimated the summary effect size using random and fixed effects models and the 95% confidence interval. A total of 1329 studies were searched, and 30 meta‐analyses with 26 health outcomes were identified that met the eligibility criteria. Carrot intake was associated with a lower risk of multiple cancer outcomes including breast cancer, lung cancer, pancreatic cancer, gastric cancer, urothelial cancer, and prostate cancer. Carotene intake was associated with a lower risk of fracture, age‐related cataract, sunburn, Alzheimer's disease, breast cancer, lung cancer, pancreatic cancer, gastric cancer, esophageal cancer, prostate cancer, and head and neck cancer (HNC). Serum carotene was inversely associated with all‐cause mortality, breast cancer, and lung cancer. Our study revealed that carrot or carotene intake could reduce the risk of various negative health outcomes. © 2023 Society of Chemical Industry.
Root vegetables are known all over the world, but they are being less and less consumed by individuals. The main purpose of this article was to summarize the benefits, health effects, and threats associated with the consumption of carrot, celery, parsley, beetroot, radish, turnip, and horseradish. They are characterized by high nutritional value due to their richness in dietary fiber, vitamins, and minerals. One of their most important features is their high content of bioactive compounds, such as polyphenols, phenols, flavonoids, and vitamin C. These compounds are responsible for antioxidant potential. Comparison of their antioxidant effects is difficult due to the lack of standardization among methods used for their assessment. Therefore, there is a need for a reference method that would allow for correct interpretation. Moreover, root vegetables are characterized by several health-promoting effects, including the regulation of metabolic parameters (glucose level, lipid profile, and blood pressure), antioxidant potential, prebiotic function, and anti-cancer properties. However, due to the type of cultivation, root vegetables are vulnerable to contaminants from the soil, such as toxic metals (lead and cadmium), pesticides, pharmaceutical residues, microplastics, and nitrates. Regardless, the low levels of toxic substances present in root vegetables do not pose health risks to the average consumer.
Background
The evidence of dietary carrot/carotene intake's effect on the association with colorectal cancer (CRC) risk is conflicted. We sought to examine the association of carrot/carotene intake with CRC incidence and mortality in the Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening cohort.
Methods
In all, 101,680 participants were enrolled between November 1993 and July 2001 from the PLCO cohort. We employed the multivariable Cox regression analyses to estimate the hazard ratios and 95% confidence interval. Subgroup analyses and interaction tests were performed to examine the potential effect modifiers. We further applied the generalized additive model to explore the non-linear trend of the exposure to cancer-related outcomes.
Results
A total of 1,100 CRC cases and 443 cancer-related deaths were documented. We noted that the 4th quintile of dietary carrot intakes was associated with a 21% lower risk of CRC incidence, compared with the lowest quintile group (full-adjusted HRquintile4vs.quintile1 = 0.79, 95%CI = 0.65–0.97, p for trend = 0.05), while the adjusted-HR was 0.95 (95%CI = 0.89–1.02) with per SD increment of carrot intakes, and no statistically significant associations were detected between dietary α-, and β-carotene intake and CRC incidence. There were no statistically significant associations observed between carrot/carotene intakes and CRC mortality. Furthermore, there were no non-linear dose-response relationships between dietary carrot, α-, and β-carotene intake and CRC incidence and mortality (all pnonlinearity > 0.05). Of note, smoking status as a modifier on the association of dietary carrot intakes with CRC incidence but not mortality was observed.
Conclusions
In summary, this large U.S. prospective cohort study indicated that a moderate consumption of carrots was associated with a lower CRC incidence, which suggested that a certain dose-range of carrots consumed might contribute to a potential cancer-prevention effect, not the more the better.
Urological cancers, namely prostate, bladder, kidney, testicular, and penile cancers, are common conditions that constitute almost one-quarter of all malignant diseases in men. Urological cancers tend to affect older individuals, and their development is influenced by modifiable metabolic, behavioral, and environmental risk factors. Phytochemicals may have cancer-fighting properties and protect against cancer development, slow its spread, and reduce the risk of cancer deaths in humans. This paper aims to review the current literature in regard to the effects of carotenoids in reducing urological cancer risk.
Peeling may result in changes in carrot’s nutritional properties; therefore, the present study focused on its effect on the retention of principal nutrients (minerals, sugars, organic acids) and antioxidants (carotenoids and phenols) in the peeled roots of two landraces (‘Carota a punta lunga’—CPL and ‘Carota a punta tonda’—CPT) and a hybrid cultivar (‘Presto’) grown in the area of the “Salterns of Margherita di Savoia” area (Puglia region). The peel had a higher concentration of cations (+92%), organic acids (+103%), carotenoids (+42%), and phenolic acids (seven times) than root flesh. For each chemical class, the most abundant components were K, malic acid, ß-carotene, and chlorogenic acid, respectively. The two landraces stand out for the accumulation of the phenolic acids and ß-carotene, whereas the peel of ‘Presto’ was distinguished by the concentration of Ca and ascorbic and pyruvic acids. The root flesh had a greater accumulation of simple sugars, nitrate (mainly in CPL), oxalic acid, and in particular in the flesh of ‘Presto’, of Na and Cl. For local varieties, peel removal seems to impact the nutritional and antioxidative properties of carrots more consistently compared to the advanced cultivar, since it represents on average 21% and 59% of the total carotenoids and phenols, respectively, of the intact roots.
Previous studies have provided limited evidence for the effect of carrot intake on bladder cancer incidence. This study aimed to evaluate the association between carrot consumption and bladder cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening cohort. PLCO enrolled 154,897 participants between November 1993 and July 2001 from 10 clinical screening centers throughout the United States. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression model adjusting for confounders. A meta-analysis was also performed based on all available prospective studies with DerSimonian and Laird random-effects model to calculate summary relative risk (RR) and 95% CI. After a median of 12.5 years of follow-up, 762 incident bladder cancer cases occurred. We found no statistically significant association between dietary carrot intake and bladder cancer risk. The multivariate-adjusted HR of bladder cancer for participants in the highest category of total carrot intake compared with those in the lowest category was 0.96 (95% CI: 0.76–1.22; P for trend = 0.436). Corresponding adjusted HR was 0.98 (95% CI 0.90–1.06) per 1 SD increment of carrot intake. A meta-analysis based on two previous cohort studies and our study also found no significant association between carrot intake and bladder cancer risk (Summary HR 1.02, 95% CI 0.95–1.10) without obvious heterogeneity between studies (P = 0.859, I² = 0.0%). In summary, analysis of the PLCO cohort did not provide evidence that dietary consumption of carrot was associated with the risk of bladder cancer.
There are few studies that evaluated the relationship between dietary diversity score (DDS) and risk of cancer. The purpose of this study was to examine the association of DDS with the risk of prostate cancer (PC) among Iranian men. This case-control study was performed among 60 cases with prostate cancer and 60 hospital-based controls. Anthropometric measurements were done and demographic information was recorded using standard protocols. A validated 160-item semi-quantitative food frequency questionnaire (FFQ) was used to assess usual dietary intakes. Also, Binary logistic regression was performed to estimate the risk of PC in relation to DDS. After controlling for several confounders (age, body mass index, physical activity, energy intake, job, education, and antihypertensive drugs usage) higher adherence to DDS (OR = 0.33; 95% CI (0.11-0.97)), fruits group (OR = 0.19; 95% CI (0.06-0.63)), and vegetables group (OR = 0.17; 95% CI (0.05 − 0.58)) were significantly associated with lower risk of PC. In contrast, greater adherence to the meat group (OR = 3.88; 95% CI (1.32-11.42)) was significantly associated with increased PC risk. Our results showed that adherence to a diet with higher DDS, especially higher amounts of fruits and vegetables and a lower amount of meat could decrease the risk of PC.
Falcarindiol (FaDOH) is a cytotoxic and anti-inflammatory polyacetylenic oxylipin found in food plants of the carrot family (Apiaceae). FaDOH has been shown to activate PPARγ and to increase the expression of the cholesterol transporter ABCA1 in cells, both of which play an important role in lipid metabolism. Thus, a common mechanism of action of the anticancer and antidiabetic properties of FaDOH may be due to a possible effect on lipid metabolism. In this study, the effect of sub-toxic concentration (5 μM) of FaDOH inside human mesenchymal stem cells (hMSCs) was studied using white light microscopy and Raman imaging. Our results show that FaDOH increases lipid content in the hMSCs cells as well as the number of lipid droplets (LDs) and that this can be explained by increased expression of PPARγ2 as shown in human colon adenocarcinoma cells. Activation of PPARγ can lead to increased expression of ABCA1. We demonstrate that ABCA1 is upregulated in colorectal neoplastic rat tissue, which indicates a possible role of this transporter in the redistribution of lipids and increased formation of LDs in cancer cells that may lead to endoplasmic reticulum stress and cancer cell death.
Bioactive C17 and C18 acetylenic oxylipins have shown to contribute to the cytotoxic, anti-inflammatory, and potential anticancer properties of terrestrial plants. These acetylenic oxylipins are widely distributed in plants belonging to the families Apiaceae, Araliaceae, and Asteraceae, and have shown to induce cell cycle arrest and/or apoptosis of cancer cells in vitro and to exert a chemopreventive effect on cancer development in vivo. The triple bond functionality of these oxylipins transform them into highly alkylating compounds being reactive to proteins and other biomolecules. This enables them to induce the formation of anti-inflammatory and cytoprotective phase 2 enzymes via activation of the Keap1–Nrf2 signaling pathway, inhibition of proinflammatory peptides and proteins, and/or induction of endoplasmic reticulum stress, which, to some extent, may explain their chemopreventive effects. In addition, these acetylenic oxylipins have shown to act as ligands for the nuclear receptor PPARγ, which play a central role in growth, differentiation, and apoptosis of cancer cells. Bioactive C17 and C18 acetylenic oxylipins appeartherefore, to constitute a group of promising lead compounds for the development of anticancer drugs. In this review, the cytotoxic, anti-inflammatory and anticancer effects of C17 and C18 acetylenic oxylipins from terrestrial plants are presented and their possible mechanisms of action and structural requirements for optimal cytotoxicity are discussed.
Carrots’ genotype and growing conditions influence their potential properties to fight against cardiovascular and metabolic diseases. The present study evaluated the influence of carrot genotypes contrasted by root color (Bolero, Presto, Karotan, Deep Purple, Kintoki and Blanche des Vosges) growing under standard, water-restricted, biotic stress (Alternaria dauci inoculation), and combined stress conditions (water restriction and A.dauci inoculation). The effect of carrots’ polyphenol and carotenoid content was assessed on endothelial and smooth muscle cells, hepatocytes, adipocytes and macrophages functions (oxidative stress, apoptosis, proliferation, lipid accumulation and inflammation). Independently of varieties or growing conditions, all carrot extracts affected vascular cells’ oxidative stress and apoptosis, and metabolic cells’ oxidative stress and lipid accumulation. Three clusters were revealed and displayed beneficial properties mostly for adipocytes function, smooth muscle cells and hepatocytes, and endothelial cells and hepatocytes, respectively. Karotan and Presto varieties exhibited endothelial tropism while Blanche des Vosges targeted adipocytes. Carrots under biotic stress are more efficient in inducing beneficial effects, with the Bolero variety being the most effective. However, extracts from carrots which grew under combined stress conditions had limited beneficial effects. This report underscores the use of certain carrot extracts as potential effective nutraceutical supplements for metabolic diseases.
Emerging epidemiological studies have assessed the potential relationship between the inflammatory potential of diet measured using the dietary inflammatory index (DII) and the risk of prostate cancer and found inconsistent results. The aim of this study was to systematically evaluate this issue using a meta-analysis approach. A comprehensive literature search of papers published through March 2019 was performed in the PubMed and EMBASE databases. The summary odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using a DerSimonian and Laird random effects model. A categorized analysis and linear and nonlinear dose-response analyses were performed. Ten studies met the inclusion criteria for our meta-analysis. The highest DII score category was associated with a significantly higher risk of prostate cancer than the lowest DII score category (OR = 1.73, 95% CI 1.34–2.23). In the dose-response analysis, the summary OR of prostate cancer for an increment of one unit of the DII was 1.10 (95% CI 1.04–1.17). The sensitivity analysis indicated that exclusion of any single study did not materially alter the pooled risk estimates. Finally, there was no evidence of significant publication bias with Begg’s test or with Egger’s test. In conclusion, this meta-analysis suggests that an increased DII is related to a higher risk of prostate cancer and that the risk increases by 10.0% per unit of the DII. However, further well-designed prospective trials with larger sample sizes should be performed to validate our preliminary findings.
Background and aim: Prostate cancer is the most common cancer among men. Several studies have investigated the effects of dietary patterns on prostate cancer risk, but this topic is still a matter of debate. This study aimed to examine the association between dietary patterns and prostate cancer risk.
Methods: In a case-control study, 60 newly diagnosed prostate cancer cases and 60 hospital-based controls were selected from two main hospitals of Shiraz, Iran. Data on dietary intakes, anthropometric features, and demographic characteristics were collected. To determine the dietary patterns factor analysis, and to estimate the odds ratios (ORs), multivariable logistic regression was performed.
Results: Two major dietary patterns were identified: Western dietary (WD) pattern and Mediterranean dietary (MD) pattern. After adjusting for potential confounders, men who had higher scores for WD pattern (above the median) were more likely to have prostate cancer (OR = 5.15; 95% CI (1.44–18.47); P = 0.01) compared with men who had lower scores. A nonsignificant inverse association was found for MD pattern (OR = 0.62; 95% CI (0.22–1.77); P = 0.37).
Conclusions: Our findings suggest that WD pattern may increase the risk of prostate cancer and the beneficial effects of MD pattern on prostate cancer risk need further research.
It is speculated that genetic variants are associated with differential responses to nutrients (known as gene–diet interactions) and that these variations may be linked to different cancer risks. In this review, we critically evaluate the evidence across 314 meta-analyses of observational studies and randomized controlled trials of dietary risk factors and the five most common cancers (breast, lung, prostate, colorectal, and stomach). We also critically evaluate the evidence across 13 meta-analyses of observational studies of gene–diet interactions for the same cancers. Convincing evidence for association was found only for the intake of alcohol and whole grains in relation to colorectal cancer risk. Three nutrient associations had highly suggestive evidence and another 15 associations had suggestive evidence. Among the examined gene–diet interactions, only one had moderately strong evidence.
Objectives
Prostate cancer is the most common cancer and the second leading cause of cancer-related deaths among men, but the contributing factors are unclear. One such may be night work because of the day/night alternation of work and the resulting disturbance of the circadian system. The purpose of the present study was to investigate the prospective relation between number of years with night work and prostate cancer in men.
Design
Cohort study comparing night and day working twins with respect to incident prostate cancer in 12 322 men.
Setting
Individuals in the Swedish Twin Registry.
Participants
12 322 male twins.
Outcome measures
Prostate cancer diagnoses obtained from the Swedish Cancer Registry with a follow-up time of 12 years, with a total number of cases=454.
Results
Multiple Cox proportional hazard regression analysis, adjusted for a number of covariates, showed no association between ever night work and prostate cancer, nor for duration of night work and prostate cancer. Analysis of twin pairs discordant for prostate cancer (n=332) showed no significant association between night work and prostate cancer.
Conclusions
The results, together with previous studies, suggest that night work does not seem to constitute a risk factor for prostate cancer.
Background
Cancer is a major disease worldwide, and many patients use complementary and alternative treatments. The purpose of this study was to identify the herbal remedies and functional foods used as complementary medicine by prostate, breast and colorectal cancer patients at speciality care facilities in Trinidad. We also sought to determine how patients rated the efficacy of these modalities compared with conventional treatment. MethodsA descriptive, cross-sectional survey was conducted using an interviewer-administered pilot-tested de novo questionnaire during the period June to August 2012 at two speciality treatment centres on the island. Data was analysed using χ2 analyses. ResultsAmong the 150 patients who reported use of herbal remedies/functional foods, soursop (Annona muricata L.) was the most popular; with 80.7 % using the leaves, bark, fruit and seeds on a regular basis. Other common herbal remedies/functional foods included wheatgrass (Triticum aestivum L.), saffron (Crocus sativus L.) and Aloe vera (L.) Burm. f. The most commonly used functional foods were beetroot (Beta vulgaris L.), carrots (Daucus carata L.) and papaya (Carica papaya L.) used by 43.3 % of patients; and these were mostly blended as a mixture. Herbal remedies and functional foods were used on a daily basis and patients believed that this modality was equally (32.0 %) or more efficacious (14.7 %) than conventional treatment. Conclusions
This survey identified the most common herbal remedies and functional foods used among prostate, breast and colorectal cancer patients in Trinidad. Although functional foods rarely pose a problem, herbs may interact with conventional chemotherapy and physicians need to inform patients regarding probable herb-drug interactions.
The previously reported association between hypertension and prostate cancer risk was controversial. We performed this systematic review and meta-analysis of all available studies to summarize evidence on this association. Studies were identified by searching PubMed, Web of Science and Chinese National Knowledge Infrastructure (CNKI) databases through January 2016. Pooled relative risks (RRs) with their corresponding 95% confidence intervals (CIs) were calculated using a random-effects model. A total of 21 published studies were included in this meta-analysis. A significant increase in the risk of prostate cancer (RR 1.08, 95% CI 1.02–1.15, P = 0.014) was observed among individuals with hypertension. There was statistically significant heterogeneity among included studies (P < 0.001 for heterogeneity, I2 = 72.1%). No obvious evidence of significant publication bias was detected by either Begg’s test (P = 0.174) or Egger’s test (P = 0.277). In conclusion, this meta-analysis indicates that hypertension may be associated with an increased risk of prostate cancer. Considering the substantial heterogeneity and residual confounding among included studies, further large-scale, well-designed prospective cohorts, as well as mechanistic studies, are urgently needed to confirm our preliminary findings.
Background: Prostate cancer is one of the most common cancers in the world. However, disparities in incidence rates worldwide have suggested that lifestyle factors, particularly diet, may play a role in its development. Carotenoids have exhibited multiple anti-cancer effects, and increased intakes of high-carotenoid foods have been shown to be protective against prostate cancer in epidemiological investigations. The aim of this project was to complete a meta-analysis of dietary intake of four carotenoids – α-carotene, β-cryptoxanthin, lutein, and zeaxanthin – to determine their role in prostate cancer incidence.
Methods: A PubMed literature search and a systematic review of the literature was performed to identify studies measuring carotenoid intake and prostate cancer risk. Estimates of OR or HR for highest versus lowest categories of intake were pooled for each individual carotenoid for case-control/NCC studies and cohort/case-cohort studies, respectively. Tests for heterogeneity and publication bias were also carried out.
Results: A total of sixteen published articles were included in the analysis. A significantly reduced risk of prostate cancer was found for higher intakes of each of the four carotenoids in case-control/NCC studies, but not for cohort/case-cohort studies. Pooled ORs for lutein (0.76, 95% CI = 0.60-0.97, p = 0.03) and lutein & zeaxanthin (0.82, 95% CI = 0.75-0.89, p = 0.00) showed the strongest risk reductions, while α-carotene (OR = 0.92, 95% CI = 0.84-1.00, p = 0.04) and β-cryptoxanthin (OR = 0.91, 95% CI = 0.83-0.99, p = 0.03) showed more modest protective effects. Cohort/case-cohort studies also expressed reduced risks for higher intakes (lutein showed no association; HR = 1.00, 95% CI = 0.91-1.10, p = 0.97), though these results were not statistically significant. No publication bias was detected, though there was significant heterogeneity between included studies.
Conclusion: There appears to be an inverse association for intake of α-carotene, β-cryptoxanthin, lutein, and zeaxanthin and prostate cancer. Increased intakes of high carotenoid foods may be protective against prostate cancer development.
Cardiovascular disease (CVD) has been the number one cause of death in the United States for approximately 114 of the last 115 years. The majority of the research on specific lifestyle factors that could contribute to CVD also suggests similar lifestyle factors cause or encourage the progression of prostate cancer. And, lifestyle changes that reduce CVD reduce the risk of developing prostate cancer. Minimal exercise, caloric excess, obesity, insulin resistance or glucose abnormalities, dyslipidemia, hypertension, and metabolic syndrome appear to increase the risk of both conditions. The largest randomized trials utilizing dietary supplements or pharmacologic agents for prostate cancer prevention (the Prostate cancer Prevention Trial – PCPT and SELECT) have also indirectly observed the relationship between CVD and prostate cancer. Lower rates of aggressive prostate cancer with low cholesterol levels and a higher risk for those with a history of heart disease were interesting findings. Dietary supplements that have not been found to be CVD protective, such as selenium and vitamin E, have not been found to be prostate protective. Additionally, overexposure to specific antioxidants in nutritionally replete populations may be encouraging cancer growth. Future trials of dietary supplements to prevent prostate cancer could be problematic because by the time a definitive trial is initiated the population in question may no longer be “deficient” in the nutrient being tested, which arguably occurred in the SELECT trial. Yet, it is also interesting that statins, aspirin, and metformin (S.A.M) are three “natural” (derived from yeast, willow bark, and French Lilac), generic, low-cost, heart healthy agents with some separate and overlapping mechanisms of action, which all appear to have the best benefit-to-risk ratio compared to any other agent available for prostate cancer prevention, especially aggressive disease, and may also play a role in slowing the progression of this disease. It is time to focus on the forest over the trees and embrace simplicity and recommend proven CVD protective lifestyle and evidence-based agents along with conventional measures for men concerned about prostate cancer.
The previously reported association between fatherhood status and prostate cancer risk was controversial. We carried out the present meta-analysis of all relevant studies to summarize evidence on this association. A comprehensive literature search of studies was performed in PubMed, Web of Science, and the Chinese National Knowledge Infrastructure (CNKI) databases, covering all the papers published from their inception to September 2015. The combined risk estimates with 95% confidence intervals (CIs) were calculated using a random effects model. Heterogeneity and publication bias were also evaluated. A total of 11 studies were finally included in this meta-analysis. We found a significantly reduced risk of prostate cancer associated with being childless (OR 0.91, 95% CI 0.87-0.96). There was statistically significant heterogeneity across the studies (P < 0.001, I(2) = 88.2%). In summary, this meta-analysis supports that being fatherless is associated with a lower risk of prostate cancer. Because of the substantial heterogeneity and residual confounding, using other study designs to further explore this association and the underling mechanism is warranted.
Systematic reviews should build on a protocol that describes the rationale, hypothesis, and planned methods of the review; few reviews report whether a protocol exists. Detailed, well-described protocols can facilitate the understanding and appraisal of the review methods, as well as the detection of modifications to methods and selective reporting in completed reviews. We describe the development of a reporting guideline, the Preferred Reporting Items for Systematic reviews and Meta-Analyses for Protocols 2015 (PRISMA-P 2015). PRISMA-P consists of a 17-item checklist intended to facilitate the preparation and reporting of a robust protocol for the systematic review. Funders and those commissioning reviews might consider mandating the use of the checklist to facilitate the submission of relevant protocol information in funding applications. Similarly, peer reviewers and editors can use the guidance to gauge the completeness and transparency of a systematic review protocol submitted for publication in a journal or other medium.
Systematic reviews and meta-analyses have become increasingly important in health care. Clinicians read them to keep up to date with their field [1],[2], and they are often used as a starting point for developing clinical practice guidelines. Granting agencies may require a systematic review to ensure there is justification for further research [3], and some health care journals are moving in this direction [4]. As with all research, the value of a systematic review depends on what was done, what was found, and the clarity of reporting. As with other publications, the reporting quality of systematic reviews varies, limiting readers' ability to assess the strengths and weaknesses of those reviews.
Several early studies evaluated the quality of review reports. In 1987, Mulrow examined 50 review articles published in four leading medical journals in 1985 and 1986 and found that none met all eight explicit scientific criteria, such as a quality assessment of included studies [5]. In 1987, Sacks and colleagues [6] evaluated the adequacy of reporting of 83 meta-analyses on 23 characteristics in six domains. Reporting was generally poor; between one and 14 characteristics were adequately reported (mean = 7.7; standard deviation = 2.7). A 1996 update of this study found little improvement [7].
In 1996, to address the suboptimal reporting of meta-analyses, an international group developed a guidance called the QUOROM Statement (QUality Of Reporting Of Meta-analyses), which focused on the reporting of meta-analyses of randomized controlled trials [8]. In this article, we summarize a revision of these guidelines, renamed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses), which have been updated to address several conceptual and practical advances in the science of systematic reviews (Box 1).
Box 1: Conceptual Issues in the Evolution from QUOROM to PRISMA
Completing a Systematic Review Is an Iterative Process
The conduct of a systematic review depends heavily on the scope and quality of included studies: thus systematic reviewers may need to modify their original review protocol during its conduct. Any systematic review reporting guideline should recommend that such changes can be reported and explained without suggesting that they are inappropriate. The PRISMA Statement (Items 5, 11, 16, and 23) acknowledges this iterative process. Aside from Cochrane reviews, all of which should have a protocol, only about 10% of systematic reviewers report working from a protocol [22]. Without a protocol that is publicly accessible, it is difficult to judge between appropriate and inappropriate modifications.
This study was performed to assess prostate biomarkers with reference to body mass index and duration of prostate cancer.
A hospital based retrospective study was undertaken using data retrieved from the register maintained in the Department of Biochemistry of Manipal Teaching Hospital, Pokhara, Nepal between 1st January, 2009 and 28th February, 2012. Biomarkers studied were prostate specific antigen (PSA), acid phosphatase (ACP) and prostatic acid phosphatase (PAP), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (γGT). Demographic data including age, duration of disease, body weight, height and body mass index (BMI) were also collected. Duration of disease was categorized into three groups: <1 year, 1-2 years and >2 years. Similarly, BMI (kg/m2) was categorized into three groups: <23 kg/m2, 23-25 kg/ m2 and >25 kg/m2. Descriptive statistics and testing of hypothesis were used for the analysis using EPI INFO and SPSS 16 software.
Out of 57 prostate cancers, serum level of PSA, ACP and PAP were increased above the cut-off point in 50 (87.5%), 30 (52.63%) and 40 (70.18%) respectively. Serum levels of PSA, ACP and PAP significantly declined with the duration of disease after diagnosis. We observed significant and inverse relation between PSA and BMI. Similar non-signficiant tendencies were apparent for ACP and PAP.
Decreasing levels of prostate biomarkers were found with the duration of prostate cancer and with increased BMI. Out of prostate biomarkers, PSA was found to be significantly decreased with the duration of disease and BMI.
Established risk factors for prostate cancer have not translated to effective prevention or adjuvant care strategies. Several epidemiologic studies suggest greater body adiposity may be a modifiable risk factor for high-grade (Gleason 7, Gleason 8-10) prostate cancer and prostate cancer mortality. However, BMI only approximates body adiposity, and may be confounded by centralized fat deposition or lean body mass in older men. Our objective was to use bioelectric impedance analysis (BIA) to measure body composition and determine the association between prostate cancer and total body fat mass (FM) fat-free mass (FFM), and percent body fat (%BF), and which body composition measure mediated the association between BMI or waist circumference (WC) with prostate cancer.
The study used a multi-centered recruitment protocol targeting men scheduled for prostate biopsy. Men without prostate cancer at biopsy served as controls (n = 1057). Prostate cancer cases were classified as having Gleason 6 (n = 402), Gleason 7 (n = 272), or Gleason 8-10 (n = 135) cancer. BIA and body size measures were ascertained by trained staff prior to diagnosis, and clinical and comorbidity status were determined by chart review. Analyses utilized multivariable linear and logistic regression.
Body size and composition measures were not significantly associated with low-grade (Gleason 6) prostate cancer. In contrast, BMI, WC, FM, and FFM were associated with an increased risk of Gleason 7 and Gleason 8-10 prostate cancer. Furthermore, BMI and WC were no longer associated with Gleason 8-10 (OR(BMI) = 1.039 (1.000, 1.081), OR(WC) = 1.016 (0.999, 1.033), continuous scales) with control for total body FFM (OR(BMI) = 0.998 (0.946, 1.052), OR(WC) = 0.995 (0.974, 1.017)). Furthermore, increasing FFM remained significantly associated with Gleason 7 (OR(FFM) = 1.030 (1.008, 1.052)) and Gleason 8-10 (OR(FFM) = 1.044 (1.014, 1.074)) after controlling for FM.
Our results suggest that associations between BMI and WC with high-grade prostate cancer are mediated through the measurement of total body FFM. It is unlikely that FFM causes prostate cancer, but instead provides a marker of testosterone or IGF1 activities involved with retaining lean mass as men age.
The relationship between obesity and risk of prostate cancer (PCa) is unclear; however, etiologic heterogeneity by subtype of PCa (localized, advanced) related to obesity was suggested. Therefore, we conducted a dose-response meta-analysis of prospective studies to assess the association between body mass index (BMI) and risk of localized and advanced PCa.
Relevant prospective studies were identified by a search of Medline and Embase databases to 03 October 2011. Twelve studies on localized PCa (1,033,009 men, 19,130 cases) and 13 on advanced PCa (1,080,790 men, 7067 cases) were identified. We carried out a dose-response meta-analysis using random-effects model.
For localized PCa, we observed an inverse linear relationship with BMI [Ptrend<0.001, relative risk (RR): 0.94 (95% confidence interval, 95% CI, 0.91-0.97) for every 5 kg/m2 increase]; there was no evidence of heterogeneity (Pheterogeneity=0.27). For advanced PCa, we observed a linear direct relationship with BMI (Ptrend=0.001, RR: 1.09 (95% CI 1.02-1.16) for every 5 kg/m2 increase); there was weak evidence of heterogeneity (Pheterogeneity=0.08). Omitting one study that contributed substantially to the heterogeneity yielded a pooled RR of 1.07 (95% CI 1.01-1.13) for every 5 kg/m2 increase (Pheterogeneity=0.26).
The quantitative summary of the accumulated evidence indicates that obesity may have a dual effect on PCa-a decreased risk for localized PCa and an increased risk for advanced PCa.
Objective: Funnel plots (plots of effect estimates against sample size) may be useful to detect bias in meta-analyses that were later contradicted by large trials. We examined whether a simple test of asymmetry of funnel plots predicts discordance of results when meta-analyses are compared to large trials, and we assessed the prevalence of bias in published meta-analyses. Design: Medline search to identify pairs consisting of a meta-analysis and a single large trial (concordance of results was assumed if effects were in the same direction and the meta-analytic estimate was within 30
Two methods for point and interval estimation of relative risk for log-linear exposure-response relations in meta-analyses of published ordinal categorical exposure-response data have been proposed. The authors compared the results of a meta-analysis of published data using each of the 2 methods with the results that would be obtained if the primary data were available and investigated the circumstances under which the approximations required for valid use of each meta-analytic method break down. They then extended the methods to handle nonlinear exposure-response relations. In the present article, methods are illustrated using studies of the relation between alcohol consumption and colorectal and lung cancer risks from the ongoing Pooling Project of Prospective Studies of Diet and Cancer. In these examples, the differences between the results of a meta-analysis of summarized published data and the pooled analysis of the individual original data were small. However, incorrectly assuming no correlation between relative risk estimates for exposure categories from the same study gave biased confidence intervals for the trend and biased P values for the tests for nonlinearity and between-study heterogeneity when there was strong confounding by other model covariates. The authors illustrate the use of 2 publicly available user-friendly programs (Stata and SAS) to implement meta-analysis for dose-response data.
Although several mechanisms have been proposed to explain the putative role of beta-carotene in cancer, no studies have investigated a possible influence of beta-carotene on caveolin-1 (cav-1) pathway, an important intracellular signaling deregulated in cancer. Here, different human colon and prostate cancer cell lines, expressing (HCT-116, PC-3 cells) or not (Caco-2, LNCaP cells) cav-1, were treated with varying concentrations of beta-carotene (0.5-30 muM) for different periods of time (3-72 h) and the effects on cell growth were investigated. The results of this study show that (i) beta-carotene acted as a growth-inhibitory agent in cav-1-positive cells, but not in cav-1-negative cells; (ii) in cav-1-positive cells, the carotenoid downregulated in a dose- and time-dependent manner the expression of cav-1 protein and messenger RNA levels and inhibited AKT phosphorylation which, in turn, stimulated apoptosis by increasing the expression of beta-catenin and c-myc and the activity of caspases-3, -7, -8 and -9; when the carotenoid was removed from culture medium, a progressive increase in cell growth was observed with respect to beta-carotene-treated cells and (iii) the transfection of cav-1 in cav-1-negative cells increased cell sensitivity to beta-carotene by inducing apoptosis. This effect was accompanied by a reduction of both cav-1 and AKT phosphorylation and by an increase of c-myc and beta-catenin expression. Silencing of c-Myc attenuated beta-carotene-induced apoptosis and beta-catenin expression. All together, these data suggest that the modulation of cav-1 pathway by beta-carotene could be a novel mechanism by which the carotenoid acts as a potent growth-inhibitory agent in cancer cells.
David Moher and colleagues introduce PRISMA, an update of the QUOROM guidelines for reporting systematic reviews and meta-analyses
Much research has been conducted relating total carotenoids--and β-carotene in particular--to risk of cancer and cardiovascular disease (CVD). Limited data are emerging to implicate the important role of α-carotene in the development of CVD or cancer.
We assessed the direct relationship between α-carotene concentrations and risk of death among 15,318 US adults 20 years and older who participated in the Third National Health and Nutrition Examination Survey Follow-up Study. We used Cox proportional hazard regression analyses to estimate the relative risk for death from all causes and selected causes associated with serum α-carotene concentrations.
Compared with participants with serum α-carotene concentrations of 0 to 1 μg/dL (to convert to micromoles per liter, multiply by 0.01863), those with higher serum levels had a lower risk of death from all causes (P < .001 for linear trend): the relative risk for death was 0.77 (95% confidence interval, 0.68-0.87) among those with α-carotene concentrations of 2 to 3 μg/dL, 0.73 (0.65-0.83) among those with concentrations of 4 to 5 μg/dL, 0.66 (0.55-0.79) among those with concentrations of 6 to 8 μg/dL, and 0.61 (0.51-0.73) among those with concentrations of 9 μg/dL or higher after adjustment for potential confounding variables. We also found significant associations between serum α-carotene concentrations and risk of death from CVD (P = .007), cancer (P = .02), and all other causes (P < .001). The association between serum α-carotene concentrations and risk of death from all causes was significant in most subgroups stratified by demographic characteristics, lifestyle habits, and health risk factors.
Serum α-carotene concentrations were inversely associated with risk of death from all causes, CVD, cancer, and all other causes. These findings support increasing fruit and vegetable consumption as a means of preventing premature death.
The authors prospectively examined the relation of fruit and vegetable intake to breast cancer risk among 51,928 women aged 21-69 years at enrollment in 1995 in the Black Women's Health Study. Dietary intake was assessed by using a validated food frequency questionnaire. Cox proportional hazards models were used to estimate incidence rate ratios and 95% confidence intervals, adjusted for breast cancer risk factors. During 12 years of follow-up, there were 1,268 incident cases of breast cancer. Total fruit, total vegetable, and total fruit and vegetable intakes were not significantly associated with overall risk of breast cancer. However, total vegetable consumption was associated with a decreased risk of estrogen receptor-negative/progesterone receptor-negative breast cancer (incidence rate ratio = 0.57, 95% confidence interval: 0.38, 0.85, for ≥2 servings/day relative to <4/week; P(trend) = 0.02). In addition, there was some evidence of inverse associations with breast cancer risk overall for cruciferous vegetable intake (P(trend) = 0.06) and for carrot intake (P(trend) = 0.02). Study findings suggest that frequent consumption of vegetables is inversely associated with risk of estrogen receptor-negative/progesterone receptor-negative breast cancer, and that specific vegetables may be associated with a decreased risk of breast cancer overall.
Mounting evidence indicates that vitamin B(6), a coenzyme involved in nearly 100 enzymatic reactions, may reduce the risk of colorectal cancer.
To conduct a systematic review with meta-analysis of prospective studies assessing the association of vitamin B(6) intake or blood levels of pyridoxal 5'-phosphate (PLP; the active form of vitamin B(6)) with risk of colorectal cancer.
Relevant studies were identified by a search of MEDLINE and EMBASE databases to February 2010, with no restrictions. We also reviewed reference lists from retrieved articles.
We included prospective studies that reported relative risk (RR) estimates with 95% confidence intervals (CIs) for the association between vitamin B(6) intake or blood PLP levels and the risk of colorectal, colon, or rectal cancer.
Two authors independently extracted data and assessed study quality. Study-specific RRs were pooled using a random-effects model.
Nine studies on vitamin B(6) intake and 4 studies on blood PLP levels were included in the meta-analysis. The pooled RRs of colorectal cancer for the highest vs lowest category of vitamin B(6) intake and blood PLP levels were 0.90 (95% CI, 0.75-1.07) and 0.52 (95% CI, 0.38-0.71), respectively. There was heterogeneity among studies of vitamin B(6) intake (P = .01) but not among studies of blood PLP levels (P = .95). Omitting 1 study that contributed substantially to the heterogeneity among studies of vitamin B(6) intake yielded a pooled RR of 0.80 (95% CI, 0.69-0.92). The risk of colorectal cancer decreased by 49% for every 100-pmol/mL increase (approximately 2 SDs) in blood PLP levels (RR, 0.51; 95% CI, 0.38-0.69).
Vitamin B(6) intake and blood PLP levels were inversely associated with the risk of colorectal cancer in this meta-analysis.
David Moher and colleagues introduce PRISMA, an update of the QUOROM guidelines for reporting systematic reviews and meta-analyses
Despite years of research and hundreds of reports on tumor markers in oncology, the number of markers that have emerged as clinically useful is pitifully small. Often, initially reported studies of a marker show great promise, but subsequent studies on the same or related markers yield inconsistent conclusions or stand in direct contradiction to the promising results. It is imperative that we attempt to understand the reasons that multiple studies of the same marker lead to differing conclusions. A variety of methodologic problems have been cited to explain these discrepancies. Unfortunately, many tumor marker studies have not been reported in a rigorous fashion, and published articles often lack sufficient information to allow adequate assessment of the quality of the study or the generalizability of study results. The development of guidelines for the reporting of tumor marker studies was a major recommendation of the National Cancer Institute–European Organisation for Research and Treatment of Cancer (NCI-EORTC) First International Meeting on Cancer Diagnostics in 2000. As for the successful CONSORT initiative for randomized trials and for the STARD statement for diagnostic studies, we suggest guidelines to provide relevant information about the study design, preplanned hypotheses, patient and specimen characteristics, assay methods, and statistical analysis methods. In addition, the guidelines suggest helpful presentations of data and important elements to include in discussions. The goal of these guidelines is to encourage transparent and complete reporting so that the relevant information will be available to others to help them to judge the usefulness of the data and understand the context in which the conclusions apply.
In meta-analysis, the assessment of graphs is widely used in an attempt to identify or rule out heterogeneity and publication
bias. A variety of graphs are available for this purpose. To date, however, there has been no comparative evaluation of the
performance of these graphs. With the objective of assessing the reproducibility and validity of graph ratings, the authors
simulated 100 meta-analyses from 4 scenarios that covered situations with and without heterogeneity and publication bias.
From each meta-analysis, the authors produced 11 types of graphs (box plot, weighted box plot, standardized residual histogram,
normal quantile plot, forest plot, 3 kinds of funnel plots, trim-and-fill plot, Galbraith plot, and L'Abbé plot), and 3 reviewers
assessed the resulting 1,100 plots. The intraclass correlation coefficients (ICCs) for reproducibility of the graph ratings
ranged from poor (ICC = 0.34) to high (ICC = 0.91). Ratings of the forest plot and the standardized residual histogram were
best associated with parameter heterogeneity. Association between graph ratings and publication bias (censorship of studies)
was poor. Meta-analysts should be selective in the graphs they choose for the exploration of their data.
The BJC is owned by Cancer Research UK, a charity dedicated to understanding the causes, prevention and treatment of cancer and to making sure that the best new treatments reach patients in the clinic as quickly as possible. The journal reflects these aims. It was founded more than fifty years ago and, from the start, its far-sighted mission was to encourage communication of the very best cancer research from laboratories and clinics in all countries. The breadth of its coverage, its editorial independence and it consistent high standards, have made BJC one of the world's premier general cancer journals. Its increasing popularity is reflected by a steadily rising impact factor.
A case-control study in Somerset and east Devon was undertaken to investigate possible risk factors for prostatic cancer. A total of 159 cases, diagnosed at Taunton. Yeovil and Exeter hospitals between May 1989 and May 1991, were identified prospectively and interviewed with a structured questionnaire. A total of 161 men diagnosed with benign prostatic hypertrophy and 164 non-urological hospital controls were given identical questionnaires. The questionnaire covered a wide range of factors identified from previous studies, but the central hypotheses for this study related to diet (fat and green vegetables), sexual activity and farming as an occupation. This study found no association between farming and risk of prostatic cancer (odds ratio = 0.74, 95% confidence interval 0.46-1.18), nor with sexual activity as measured by number of sexual partners (chi-squared test for trend P = 0.52). A history of sexually transmitted disease was not significantly associated with prostatic cancer, but the numbers involved were very small and the odds ratio of 2.06 (0.38-11.2) is consistent with the hypothesis. A range of questions aimed at eliciting dietary fat intake produced no significant associations, although meat consumption showed increasing risk with increasing consumption (test for trend P = 0.005). Increased consumption of leafy green vegetables was associated with lower risk, but not significantly so (test for trend P = 0.16). As expected with so many factors investigated, some statistically significant associations were found, although these can only be viewed as hypothesis generating in this context. These included apparent protective effects of circumcision and high fish consumption.
We interviewed 328 men diagnosed with prostate cancer before the age of 75 years and 328 age-matched population controls. The principal hypotheses were that risk would increase with a high intake of total or saturated fat and would decrease with a high intake of carotene (beta-carotene equivalents) or lycopene. We also examined the associations of other nutrients and foods with risk. There was no evidence for an association between fat intake and risk, although the average fat intake was high and the range of fat intakes was narrow (medians of lower and upper thirds of percentage of energy from fat among controls were 34.3% and 42.9% respectively). Risk was lower in subjects with higher carotene intake: odds ratios 0.65 (95% CI 0.45-0.94) and 0.76 (0.53-1.10) in the middle and upper thirds of carotene intake respectively (P for trend = 0.150). Lycopene was not associated with risk. Among 13 other nutrients examined, the odds ratios in the top third of intake were below 0.8 for: potassium, 0.74 (0.51-1.09; P for trend = 0.054); zinc, 0.73 (0.49-1.08; P for trend = 0.126); iodine, 0.75 (0.51-1.11; P for trend = 0.077); vitamin B6 food only, 0.77 (0.53-1.12; P for trend = 0.077); and vitamin B6 including supplements, 0.70 (0.48-1.03; P for trend = 0.029). Among 18 foods examined, statistically significant associations were observed for: garlic as food, > or = 2/week vs never, 0.56 (0.33-0.93); garlic including supplements, > or = 2/week vs never, 0.60 (0.37-0.96); baked beans, > or = 2/week vs < 1/month, 0.57 (0.34-0.95); and garden peas, > or = 5/week vs < or = 3/month, 0.35 (0.13-0.91). This study does not support the hypothesis that fat increases risk and is equivocal in relation to carotene. The possible relationships of vitamin B6, garlic, beans and peas with risk for prostate cancer should be further investigated.
Funnel plots (plots of effect estimates against sample size) may be useful to detect bias in meta-analyses that were later contradicted by large trials. We examined whether a simple test of asymmetry of funnel plots predicts discordance of results when meta-analyses are compared to large trials, and we assessed the prevalence of bias in published meta-analyses.
Medline search to identify pairs consisting of a meta-analysis and a single large trial (concordance of results was assumed if effects were in the same direction and the meta-analytic estimate was within 30% of the trial); analysis of funnel plots from 37 meta-analyses identified from a hand search of four leading general medicine journals 1993-6 and 38 meta-analyses from the second 1996 issue of the Cochrane Database of Systematic Reviews.
Degree of funnel plot asymmetry as measured by the intercept from regression of standard normal deviates against precision.
In the eight pairs of meta-analysis and large trial that were identified (five from cardiovascular medicine, one from diabetic medicine, one from geriatric medicine, one from perinatal medicine) there were four concordant and four discordant pairs. In all cases discordance was due to meta-analyses showing larger effects. Funnel plot asymmetry was present in three out of four discordant pairs but in none of concordant pairs. In 14 (38%) journal meta-analyses and 5 (13%) Cochrane reviews, funnel plot asymmetry indicated that there was bias.
A simple analysis of funnel plots provides a useful test for the likely presence of bias in meta-analyses, but as the capacity to detect bias will be limited when meta-analyses are based on a limited number of small trials the results from such analyses should be treated with considerable caution.
This population-based case-control study investigated associations between prostate cancer risk and dietary intake of the carotenoids beta-carotene and lycopene and their major plant food sources, including carrots, green leafy vegetables, and tomato-based foods. The study was carried out in Auckland, New Zealand, during 1996-1997 and recruited 317 prostate cancer cases and 480 controls. The authors found that dietary intake of beta-carotene and its main vegetable sources was largely unassociated with prostate cancer risk, whereas intake of lycopene and tomato-based foods was weakly associated with a reduced risk. These results suggest that in contrast to the findings regarding many types of cancers, vegetables rich in beta-carotene are not protective against prostate cancer. However, lycopene from tomato-based foods was found to be associated with a small reduction in risk.
We study recently developed nonparametric methods for estimating the number of missing studies that might exist in a meta-analysis and the effect that these studies might have had on its outcome. These are simple rank-based data augmentation techniques, which formalize the use of funnel plots. We show that they provide effective and relatively powerful tests for evaluating the existence of such publication bias. After adjusting for missing studies, we find that the point estimate of the overall effect size is approximately correct and coverage of the effect size confidence intervals is substantially improved, in many cases recovering the nominal confidence levels entirely. We illustrate the trim and fill method on existing meta-analyses of studies in clinical trials and psychometrics.
This meta-analysis was conducted to evaluate the association between intake of carotenoids and risk of esophageal cancer. A systematic search using PubMed, Cochrane Library, Web of Science, Scopus, CNKI, and CBM (updated to 6 May 2012) identified ten articles meeting the inclusion criteria with 1,958 cases of esophageal cancer and 4,529 controls. Higher intake of beta-carotene, alpha-carotene, lycopene, beta-cryptoxanthin, lutein, and zeaxanthin reduced esophageal cancer risk with pooled ORs of 0.58 (95% CI 0.44, 0.77), 0.81 (95% CI 0.70, 0.94), 0.75 (95% CI 0.64, 0.86), 0.80 (95% CI 0.66, 0.97), and 0.71 (95% CI 0.59, 0.87), respectively. In subgroup analyses, beta-carotene showed protective effects against esophageal adenocarcinoma in studies located in Europe and North America. Alpha-carotene, lycopene, and beta-cryptoxanthin showed protection against esophageal squamous cell cancer. This meta-analysis suggested that higher intake of carotenoids (beta-carotene, alpha- carotene, lycopene, beta-cryptoxanthin, lutein, and zeaxanthin) is associated with lower risk of esophageal cancer. Further research with large-sample studies need to be conducted to better clarify the potentially protective mechanisms of carotenoid associations risk of different types of esophageal cancer.
Background:
There are inconsistent data regarding the association between metabolic factors, separately and combined, and the risk of prostate cancer and death from prostate cancer.
Methods:
In the Metabolic Syndrome and Cancer Project (Me-Can), data on body mass index (BMI); blood pressure; and blood levels of glucose, cholesterol, and triglycerides were collected for 289,866 men. Cox proportional hazard models were used to calculate relative risks (RRs) by exposures in quintiles as well as for z scores (with a mean of 0 and a standard deviation of 1) together with a composite sum of scores to assess the combined effect of metabolic factors. RRs were corrected for random errors in measurement.
Results:
During a mean follow-up of 12 years, 6673 men were diagnosed with prostate cancer and 961 died of the disease. Men with high levels of glucose and triglycerides were found to have a decreased risk of prostate cancer: top versus bottom quintile of glucose: RR, 0.82 (95% confidence interval [95% CI], 0.62-1.08; P value for trend = .03) and top versus bottom quintile of triglycerides: RR, 0.88 (95% CI, 0.74-1.04; P value for trend = .001). High BMI, elevated blood pressure, and a high composite z score were found to be associated with an increased risk of death from prostate cancer: top versus bottom quintile of BMI: RR, 1.36 (95% CI, 1.08-1.71); systolic blood pressure: RR, 1.62 (95% CI, 1.07-2.45); and per 1-unit increase of the composite z score: RR, 1.13 (95% CI, 1.03-1.25).
Conclusions:
The authors found no evidence of an association between high levels of metabolic factors and the risk of prostate cancer, but high BMI, elevated blood pressure, and a composite score of all metabolic factors were associated with an increased risk of death from prostate cancer.
To conduct a systematic review of prospective studies assessing the association of vitamin D intake or blood levels of 25-hydroxyvitamin D [25(OH)D] with the risk of colorectal cancer using meta-analysis.
Relevant studies were identified by a search of MEDLINE and EMBASE databases before October 2010 with no restrictions. We included prospective studies that reported relative risk (RR) estimates with 95% CIs for the association between vitamin D intake or blood 25(OH)D levels and the risk of colorectal, colon, or rectal cancer. Approximately 1,000,000 participants from several countries were included in this analysis.
Nine studies on vitamin D intake and nine studies on blood 25(OH)D levels were included in the meta-analysis. The pooled RRs of colorectal cancer for the highest versus lowest categories of vitamin D intake and blood 25(OH)D levels were 0.88 (95% CI, 0.80 to 0.96) and 0.67 (95% CI, 0.54 to 0.80), respectively. There was no heterogeneity among studies of vitamin D intake (P = .19) or among studies of blood 25(OH)D levels (P = .96). A 10 ng/mL increment in blood 25(OH)D level conferred an RR of 0.74 (95% CI, 0.63 to 0.89).
Vitamin D intake and blood 25(OH)D levels were inversely associated with the risk of colorectal cancer in this meta-analysis.
In this study, we evaluated the efficacy of lycopene against the growth of prostate cancer in vivo.
Athymic nude mice were implanted subcutaneously with human androgen-independent prostate carcinoma PC-3 cells. They were supplemented with a low or a high dose of lycopene (4 and 16 mg/kg) and a single dose of β-carotene (16 mg/kg) twice a week for 7 wk. At the end of the experiment, both lycopene and β-carotene strongly inhibited the tumor growth, as evidenced by the decrease in tumor volume and tumor weight. High-dosage lycopene and β-carotene significantly decreased the expression of proliferating cell nuclear antigen in tumor tissues and increased the levels of insulin-like growth factor-binding protein-3 in plasma. In addition, high-dosage lycopene supplementation significantly decreased the vascular endothelial growth factor (VEGF) levels in plasma. In contrast, β-carotene supplementation significantly increased the VEGF levels, as compared with tumor control group.
Lycopene and β-carotene supplementation suppressed the growth of prostate tumor cells, and the effects are likely associated with reduction of proliferation (attenuation of proliferating cell nuclear antigen expression) and with interference of the insulin-like growth factor 1 signaling (increased plasma insulin-like growth factor-binding protein-3 levels). Furthermore, the inhibition of VEGF by lycopene suggests that the antitumor mechanisms of lycopene also involve anti-angiogenesis.
Estimates of the worldwide incidence and mortality from 27 cancers in 2008 have been prepared for 182 countries as part of the GLOBOCAN series published by the International Agency for Research on Cancer. In this article, we present the results for 20 world regions, summarizing the global patterns for the eight most common cancers. Overall, an estimated 12.7 million new cancer cases and 7.6 million cancer deaths occur in 2008, with 56% of new cancer cases and 63% of the cancer deaths occurring in the less developed regions of the world. The most commonly diagnosed cancers worldwide are lung (1.61 million, 12.7% of the total), breast (1.38 million, 10.9%) and colorectal cancers (1.23 million, 9.7%). The most common causes of cancer death are lung cancer (1.38 million, 18.2% of the total), stomach cancer (738,000 deaths, 9.7%) and liver cancer (696,000 deaths, 9.2%). Cancer is neither rare anywhere in the world, nor mainly confined to high-resource countries. Striking differences in the patterns of cancer from region to region are observed.
Each year, the American Cancer Society estimates the number of new cancer cases and deaths expected in the United States in the current year and compiles the most recent data on cancer incidence, mortality, and survival based on incidence data from the National Cancer Institute, Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries and mortality data from the National Center for Health Statistics. Incidence and death rates are standardized by age to the 2000 United States standard million population. A total of 1,479,350 new cancer cases and 562,340 deaths from cancer are projected to occur in the United States in 2009. Overall cancer incidence rates decreased in the most recent time period in both men (1.8% per year from 2001 to 2005) and women (0.6% per year from 1998 to 2005), largely because of decreases in the three major cancer sites in men (lung, prostate, and colon and rectum [colorectum]) and in two major cancer sites in women (breast and colorectum). Overall cancer death rates decreased in men by 19.2% between 1990 and 2005, with decreases in lung (37%), prostate (24%), and colorectal (17%) cancer rates accounting for nearly 80% of the total decrease. Among women, overall cancer death rates between 1991 and 2005 decreased by 11.4%, with decreases in breast (37%) and colorectal (24%) cancer rates accounting for 60% of the total decrease. The reduction in the overall cancer death rates has resulted in the avoidance of about 650,000 deaths from cancer over the 15-year period. This report also examines cancer incidence, mortality, and survival by site, sex, race/ethnicity, education, geographic area, and calendar year. Although progress has been made in reducing incidence and mortality rates and improving survival, cancer still accounts for more deaths than heart disease in persons younger than 85 years of age. Further progress can be accelerated by applying existing cancer control knowledge across all segments of the population and by supporting new discoveries in cancer prevention, early detection, and treatment.
The effect of vegetable and fruit consumption on breast cancer risk is controversial. We examined the association between vegetable and fruit intake and breast cancer risk in a hospital-based case-control study conducted in Guangdong, China. Four hundred and thirty-eight cases were frequency matched to 438 controls by age (5-year interval) and residence (rural/urban). Dietary intake was assessed by face-to-face interviews using a validated food frequency questionnaire. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence interval (CI) after adjusting for various potential confounders. Total vegetable and fruit intake was found to be inversely associated with breast cancer risk. The ORs of the highest quartile relative to the lowest quartile of total vegetable and fruit intake were 0.28 (95% CI 0.18-0.43) and 0.53 (95% CI 0.34-0.82), respectively. Consumption of individual vegetable and fruit groups such as dark green leafy vegetables, cruciferous vegetables, carrots and tomatoes, banana, watermelon/papaya/cantaloupe were all inversely and significantly related with breast cancer risk. An inverse association was also observed for vitamin A, carotene, vitamin C, vitamin E, and fiber intake. These data indicate that greater intake of vegetables and fruits is associated with a decreased risk of breast cancer among Chinese women residing in Guangdong.
A high consumption of non-starchy vegetables and fruits likely decreases the risk of gastric cancer, but no specific constituent of plant foods has been consistently identified to explain this association.
We considered several micronutrients and minerals in an Italian case-control study conducted between 1997 and 2007, including 230 patients with incident, histologically confirmed gastric cancer and 547 matched controls, admitted with acute conditions. Micronutrients computation was based on a validated and reproducible food frequency questionnaire, through an Italian food composition database. We estimated odds ratios (ORs) using conditional logistic regression, adjusted for energy intake and selected covariates.
We found decreased ORs for the highest versus lowest quartile of vitamin E (OR=0.50), alpha-carotene (OR=0.52) and beta-carotene (OR=0.42) intake. Gastric cancer was directly associated with sodium, with ORs of 2.22 for the second, 2.56 for the third and 2.46 for the fourth quartile of intake. No significant relation emerged with iron, calcium, potassium, zinc, vitamin C, thiamin, riboflavin, niacin, vitamin B6, folate, vitamin D, retinol, beta-cryptoxanthin, lycopene and lutein plus zeaxanthin.
Our data support a favourable effect on gastric cancer of vitamin E and selected carotenoids and a detrimental effect of sodium even at intermediate levels of intake.
The relationship between intake of various indicator foods and beverages and risk of prostatic cancer was assessed in 271 cases of prostatic cancer and 685 hospital controls recruited in two areas of northern Italy, the province of Pordenone and the greater Milan area. Increased risks were found for more frequent intake of meat [odds ratio (OR) in the highest vs. lowest consumption tertile = 1.4, 95% confidence interval (CI) 1.0-2.0], milk (OR = 1.6, 95% CI 1.1-2.4), fresh fruit (OR = 1.4, 95% CI 1.0-2.1), and vegetables (OR = 1.4, 95% CI 0.9-2.2). After allowance for the reciprocal confounding effect of various dietary