Article

Cruciferous vegetable intake is inversely associated with lung cancer risk among smokers: A case-control study

Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.
BMC Cancer (Impact Factor: 3.36). 04/2010; 10(1):162. DOI: 10.1186/1471-2407-10-162
Source: PubMed

ABSTRACT

Inverse associations between cruciferous vegetable intake and lung cancer risk have been consistently reported. However, associations within smoking status subgroups have not been consistently addressed.
We conducted a hospital-based case-control study with lung cancer cases and controls matched on smoking status, and further adjusted for smoking status, duration, and intensity in the multivariate models. A total of 948 cases and 1743 controls were included in the analysis.
Inverse linear trends were observed between intake of fruits, total vegetables, and cruciferous vegetables and risk of lung cancer (ORs ranged from 0.53-0.70, with P for trend < 0.05). Interestingly, significant associations were observed for intake of fruits and total vegetables with lung cancer among never smokers. Conversely, significant inverse associations with cruciferous vegetable intake were observed primarily among smokers, in particular former smokers, although significant interactions were not detected between smoking and intake of any food group. Of four lung cancer histological subtypes, significant inverse associations were observed primarily among patients with squamous or small cell carcinoma - the two subtypes more strongly associated with heavy smoking.
Our findings are consistent with the smoking-related carcinogen-modulating effect of isothiocyanates, a group of phytochemicals uniquely present in cruciferous vegetables. Our data support consumption of a diet rich in cruciferous vegetables may reduce the risk of lung cancer among smokers.

Download full-text

Full-text

Available from: Vijayvel Jayaprakash
  • Source
    • "In subsequent studies, researchers conducted two case-control analyses of the effects of cruciferous-vegetable intake on lung cancer risk. These later studies confirmed a decreased risk of lung cancer in those with the highest cruciferous vegetable intake, especially in current smokers [40,41]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Decreasing the risk of lung cancer, or preventing its development in high-risk individuals, would have a huge impact on public health. The most effective means to decrease lung cancer incidence is to eliminate exposure to carcinogens. However, with recent advances in the understanding of pulmonary carcinogenesis and the identification of intermediate biomarkers, the prospects for the field of chemoprevention research have improved dramatically. Here we review the most recent research in lung cancer chemoprevention-focusing on those agents that have been investigated in human clinical trials. These agents fall into three major categories. First, oxidative stress plays an important role in pulmonary carcinogenesis; and therefore, antioxidants (including vitamins, selenium, green tea extracts, and isothiocyanates) may be particularly effective in preventing the development of lung cancer. Second, inflammation is increasingly accepted as a crucial factor in carcinogenesis, and many investigators have focused on anti-inflammatory agents, such as glucocorticoids, NSAIDs, statins, and PPARγ agonists. Finally, the PI3K/AKT/mTOR pathway is recognized to play a central role in tobacco-induced carcinogenesis, and inhibitors of this pathway, including myoinositol and metformin, are promising agents for lung cancer prevention. Successful chemoprevention will likely require targeting of multiple pathways to carcinogenesis-both to minimize toxicity and maximize efficacy.
    Full-text · Article · Mar 2013 · Cancers
  • Source
    • "Tobacco smoking is the major risk factor for the development of lung cancer and about 80–90% of lung cancers are attributable to cigarette smoking [5]. Cigarette smoke contains about 4000 chemicals— at least 250 of them are known to be harmful and more than 60 are known to be carcinogenic [6]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: CYP1A1, CYP2A6andCHRNA5are biologically plausible genes as risk factors for lung cancer but no studies have been reported in the Bangladeshi population. Methods:We conducted this study to determine the prevalence and role ofCYP1A1, CYP2A6andCHRNA5poly-morphisms together with tobacco smoking in the development of lung cancer in Bangladesh. A case–control study was carried out on 106 lung cancer patients and 116 controls to investigate three allelic variants of the CYP1A1gene—rs4646903, rs1048943 and rs1799814; 2 variants of CYP2A6(CYP2A6*1B1, CYP2A6*4)and1 variant ofCHRNA5(rs16969968) using Polymerase Chain Reaction Restriction Fragment Length Polymorphism. Results:Lung cancer risk was estimated as odds ratio (OR) and 95% confidence interval (CI) using unconditional logistic regression models adjusting for age, sex and smoking. A significantly elevated lung cancer risk was associated with heterozygous, mutant and combined heterozygous plus mutant variants of CYP1A1 rs4646903. Asignificant association was also found for heterozygous and heterozygous plus mutant variants of rs1048943 which was in linkage disequilibrium with rs4646903. The risk of lung cancer was decreased significantly in individuals carrying at least one CYP2A6 deletion (CYP2A6*4) allele. No association with lung cancer risk was found forCHRNA5rs16969968. When stratified by smoking, the effects of CYP1A1 and CYP2A6 polymorphisms on lung cancer susceptibility were found to be significant only in heavy smokers who had smoked 40 pack years or more (54% of all cases) but no associations were seen for lighter smokers. No association was also found with any polymorphism in the non-smokers in this study. Conclusions:Our results indicate that the CYP1A1*2B allele (rs4646903 and rs1048943) is associated with an in-creased lung cancer risk and CYP2A6*4 is associated with a decreased lung cancer risk in the study population
    Full-text · Article · Feb 2013 · Clinica chimica acta; international journal of clinical chemistry
  • Source
    • "Tobacco smoking is the major risk factor for the development of lung cancer and about 80–90% of lung cancers are attributable to cigarette smoking [5]. Cigarette smoke contains about 4000 chemicals— at least 250 of them are known to be harmful and more than 60 are known to be carcinogenic [6]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: CYP1A1, CYP2A6 and CHRNA5 are biologically plausible genes as risk factors for lung cancer but no studies have been reported in the Bangladeshi population. Methods: We conducted this study to determine the prevalence and role of CYP1A1, CYP2A6 and CHRNA5 polymorphisms together with tobacco smoking in the development of lung cancer in Bangladesh. A case-control study was carried out on 106 lung cancer patients and 116 controls to investigate three allelic variants of the CYP1A1 gene-rs4646903, rs1048943 and rs1799814; 2 variants of CYP2A6 (CYP2A6*1B1, CYP2A6*4) and 1 variant of CHRNA5 (rs16969968) using Polymerase Chain Reaction Restriction Fragment Length Polymorphism. Results: Lung cancer risk was estimated as odds ratio (OR) and 95% confidence interval (CI) using unconditional logistic regression models adjusting for age, sex and smoking. A significantly elevated lung cancer risk was associated with heterozygous, mutant and combined heterozygous plus mutant variants of CYP1A1 rs4646903. A significant association was also found for heterozygous and heterozygous plus mutant variants of rs1048943 which was in linkage disequilibrium with rs4646903. The risk of lung cancer was decreased significantly in individuals carrying at least one CYP2A6 deletion (CYP2A6*4) allele. No association with lung cancer risk was found for CHRNA5 rs16969968. When stratified by smoking, the effects of CYP1A1 and CYP2A6 polymorphisms on lung cancer susceptibility were found to be significant only in heavy smokers who had smoked 40 pack years or more (54% of all cases) but no associations were seen for lighter smokers. No association was also found with any polymorphism in the non-smokers in this study. Conclusions: Our results indicate that the CYP1A1*2B allele (rs4646903 and rs1048943) is associated with an increased lung cancer risk and CYP2A6*4 is associated with a decreased lung cancer risk in the study population.
    Full-text · Article · Nov 2012 · Clinica chimica acta; international journal of clinical chemistry
Show more