Motoki Iwasaki

National Cancer Center, Japan, Edo, Tōkyō, Japan

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Publications (223)947.33 Total impact

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    ABSTRACT: Dietary fiber may reduce the risk of prostate cancer, possibly by increasing circulating concentrations of sex hormone-binding globulin and improving insulin sensitivity. However, results from previous epidemiologic studies of fiber intake and prostate cancer are inconsistent, and to our knowledge, no study has comprehensively evaluated the effects of soluble and insoluble fiber on prostate cancer in Asia. The objective was to examine the association between fiber intake and prostate cancer in Japanese men. We conducted a population-based prospective study in 43,435 Japanese men aged 45-74 y. Participants responded to a validated questionnaire, which included 138 food items. Follow-up was from 1995 through 2009. HRs and 95% CIs of incidence were calculated according to quartiles of fiber intake. During the 11.6-y follow-up, of the 825 men newly diagnosed with prostate cancer, 213 had advanced-stage cancer, 582 had organ-localized disease, and 30 had an undetermined stage of disease. Among them, 217 cases were detected by subjective symptoms. Total fiber was not associated with total or advanced prostate cancer, with respective multivariable HRs for the highest and lowest quartiles of 1.00 (95% CI: 0.77, 1.29; P-trend = 0.97) and 0.67 (95% CI: 0.42, 1.07; P-trend = 0.30). Total fiber and insoluble fiber intake were associated with a decreased risk of advanced cancers detected by subjective symptoms, with multivariate HRs (95% CIs) across increasing quartiles of 1.00, 0.58, 0.62, and 0.44 (0.21, 0.92; P-trend = 0.05) for total fiber and 1.00, 0.60, 0.52, and 0.46 (0.22, 0.93; P-trend = 0.04) for insoluble fiber. Soluble fiber intake showed no association with prostate cancer. Dietary fiber is inversely associated with advanced prostate cancer detected by subjective symptoms even among populations with relatively low intake, such as Japanese. These results suggest that a very low intake of dietary fiber is associated with an increased risk of prostate cancer. © 2015 American Society for Nutrition.
    American Journal of Clinical Nutrition 01/2015; 101(1):118-25. · 6.50 Impact Factor
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    ABSTRACT: Background: Evidence suggests that estrogen plays a preventive role in primary liver cancer development, and it might be thought that isoflavones, which are structurally similar to estrogens and bind to estrogen receptors, are associated with the risk of liver cancer. We investigated this suspected association by measuring plasma concentrations of isoflavones in a nested case-control study of a population-based prospective cohort in Japan. Methods: From 18,628 target participants aged 40 to 69 years who returned the baseline questionnaire and provided blood samples, we selected those with either hepatitis B or hepatitis C virus infection at baseline (n=1,544). Among these, 90 (28 women and 62 men) were newly diagnosed with primary liver cancer from 1993 through 2006; they were matched with 175 controls (54 women and 121 men). Plasma concentrations of isoflavones (genistein, daidzein, glycitein, and equol) were measured using triple quadrupole tandem liquid chromatography-mass spectrometry. The odds ratios of liver cancer development based on plasma concentrations were estimated with a conditional logistic regression model. Results: Basically, distributions of plasma isoflavone concentrations did not differ between the cases and controls. No statistically significant associations of genistein, daidzein, glycitein, and equol with primary liver cancer risk were found in either women or men. Conclusions: In middle-aged Japanese women and men with hepatitis virus infection, plasma isoflavones were unassociated with the occurrence of primary liver cancer. Impact: The role of isoflavones in liver carcinogenesis merits further study using both biomarkers and data on dietary intake of isoflavones. Copyright © 2014, American Association for Cancer Research.
    Cancer Epidemiology Biomarkers & Prevention 12/2014; · 4.32 Impact Factor
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    ABSTRACT: The aim of the study was to investigate trends in cancer prognosis by examining the relationship between period of diagnosis and probability of death from cancer in a population-based cohort. Within a cohort of Japanese men and women aged 40-69 years and free of prior diagnosis of cancer and cardiovascular disease at baseline, data from 4403 patients diagnosed with cancer between 1990 and 2006 and followed up until 2012 were analyzed using survival regression models to assess the presence of an effect of the period of diagnosis (before 1998 versus after 1998) on the risk of dying from cancer. We noted a significant decrease in risk of dying from cancer among individuals diagnosed after 1998 with lung cancer (hazard ratio [HR]=0.676 [0.571-0.800]) or colorectal cancer (HR=0.801 [0.661-0.970]). A decrease in the estimated five-year probability of death from cancer was also noted between the first (before 1998) and the second (after 1998) period of diagnosis for lung and colorectal cancers (e.g., 85.4% vs. 73.3% for lung cancer and 44.6% vs. 37.7% for colorectal cancer, respectively, for stage III in men aged 60 at diagnosis). This study presented the first scientific evidence of improvement in prognosis for lung and colorectal cancer patients in a population-based cohort in Japan. Our results suggest that recent advances in cancer treatment could have influenced cancer survival differently among lung, colorectal and gastric cancers. Copyright © 2014 Elsevier Ltd. All rights reserved.
    Cancer Epidemiology 12/2014; · 2.56 Impact Factor
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    ABSTRACT: The association between alcohol consumption, genetic polymorphisms of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), and gastric cancer risk is not completely understood. We investigated the association between genetic polymorphisms ADH1B (rs1229984), ADH1C (rs698), and ALDH2 (rs671), alcohol consumption, and the risk of gastric cancer among Japanese subjects in a population-based, nested, case-control study (1990-2004). Among 36 745 subjects who answered the baseline questionnaire and provided blood samples, 457 new gastric cancer cases matched to 457 controls were used in the analysis. The odds ratios (OR) and corresponding 95% confidence intervals (CI) were calculated using logistic regression models. No association was observed between alcohol consumption, ADH1B (rs1229984), ADH1C (rs698), and ALDH2 (rs671) polymorphisms, and gastric cancer risk. However, considering gene-environmental interaction, ADH1C G allele carriers who drink ≥150 g/week of ethanol had a 2.5-fold increased risk of gastric cancer (OR = 2.54, 95% CI = 1.05-6.17) relative to AA genotype carriers who drink 0 to <150 g/week (P for interaction = 0.02). ALDH2 A allele carriers who drink ≥150 g/week also had an associated increased risk (OR = 2.08, 95% CI = 1.05-4.12) relative to GG genotype carriers who drink 0 to < 150 g/week (P for interaction = 0.08). To find the relation between alcohol consumption and gastric cancer risk, it is important to consider both alcohol consumption level and ADH1C and ALDH2 polymorphisms. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Carcinogenesis 12/2014; · 5.27 Impact Factor
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    ABSTRACT: Non-participants to psychosocial studies have been shown to have higher mortality, and mortality differs between partial and complete responders to psychosocial questionnaires. Yet, there is very little information available directly linking survey response status with completing suicide. The study population consisted of the participants of the Japanese Public Health Center-based prospective study. Ninety-nine thousand four hundred thirty-nine subjects who returned the 10-year follow-up questionnaire and 31 754 individuals who did not return the questionnaire were included in our analyses. The risk of dying by suicide according to response status was estimated by Cox regression models. There were 358 suicides during 1 128 831 person-years of follow-up (mean follow-up time: 8.6 years). Of those who returned the questionnaire, 53.9% were full responders, 42.8% were partial non-responders, and 3.3% were complete non-responders. The risk of suicide was increased for both complete non-responders [hazard ratio (HR) = 1.84, 95% confidence interval (CI), 0.51, 6.64] and partial non-responders (HR = 1.36, 95% CI, 0.999, 1.84) to the questionnaire as a whole. The adjusting variables explained around 40% of the risk for complete non-responders whereas they did not explain the increased risk of suicide for partial non-responders. The risk of dying by suicide was significantly increased for partial non-responders to the subscale on coping (HR = 1.36, 95% CI, 1.01, 1.85) and for complete non-responders to questions on sleep (HR = 2.07, 95% CI, 1.03, 4.16). Partial and complete non-responders have increased suicide risk compared with complete non-responders. More than one non-responder category should therefore be considered when interpreting data pertaining to psychosocial questionnaires in longitudinal studies. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
    European journal of public health. 12/2014;
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    ABSTRACT: Coffee is a commonly consumed beverage which contains several potential anticarcinogenic and chemopreventive compounds, and has been hypothesized to have protective effects in colorectal neoplasia. However, the limited available data on coffee consumption in relation to colorectal adenoma (CRA), a precursor lesion to most colorectal cancers, remain largely inconsistent. In this study, we evaluated the association of coffee intake with the risk of CRA in a middle-aged Japanese population. Study subjects were selected from examinees who underwent total colonoscopy as part of a cancer screening program and responded to self-administered dietary and lifestyle questionnaires. A total of 738 patients with adenoma and 697 controls were included in the study. Coffee intake was assessed with a food frequency questionnaire, and divided into quartiles based on the distribution among controls. Unconditional logistic regression models were used to estimate odds ratio (OR) and 95% confidence interval (CI) of CRA, with adjustment for potential confounding factors. High coffee consumption was associated with a reduced risk of CRA, with a multivariate-adjusted OR for the highest versus lowest quartile of coffee intake of 0.67 (95% CI=0.48–0.93; Ptrend=0.02). The inverse association of coffee intake was limited to proximal (OR=0.64; 95%CI= 0.44–0.95; Ptrend=0.04) and distal colon adenoma (OR=0.62; 95%CI=0.39–0.99; Ptrend=0.06), and appeared to be more evident with small (OR=0.68; 95%CI=0.49–0.96; Ptrend=0.04) and single adenomas (OR=0.65; 95%CI=0.44–0.95; Ptrend=0.02). Green tea intake was not found to be associated with CRA risk. This study provides support for the protective effect of coffee drinking on colon adenomas, a precursor of colon cancer. This article is protected by copyright. All rights reserved.
    International Journal of Cancer 12/2014; · 6.20 Impact Factor
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    ABSTRACT: In a three-stage genome-wide association study among East Asian women including 22,780 cases and 24,8 controls, we identified 3 genetic loci newly associated with breast cancer risk, including rs4950 at q32. (in intron 2 of the ZC3H11A gene; P = 8.82 × 0 −9), rs0474352 at 5q4.3 (near the ARRDC3 gene; P = .67 × 0 −9) and rs2290203 at 5q26. (in intron 4 of the PRC1 gene; P = 4.25 × 0 −8). We replicated these associations in 6,003 cases and 4,335 controls of European ancestry (P = 0.030, 0.004 and 0.00, respectively). Data from the ENCODE Project suggest that variants rs4950 and rs0474352 might be located in an enhancer region and transcription factor binding sites, respectively. This study provides additional insights into the genetics and biology of breast cancer. Breast cancer is one of the most common malignancies among women worldwide. Genetic factors have a substantial role in breast cancer etiology 1,2 . Thus far, genome-wide association studies (GWAS) have identified approximately 75 genetic loci associated with breast cancer risk 2–5 . With the exception of the studies we have conducted among East Asian women 6–9 and one study conducted among women of African ancestry 10 , all other published GWAS have been conducted among women of European ancestry. Genetic risk variants identified thus far from GWAS explain only about 10% of familial risk for breast cancer in East Asian women 3 . Given the dif-ferences in genetic architecture and environmental exposures for women of European and East Asian ancestry, additional GWAS need to be conducted among East Asian women to study the genetic basis of breast cancer risk. The current study was conducted as part of the Asia Breast Cancer Consortium (ABCC) to search for additional susceptibility loci for breast cancer. Included in this study are data obtained from 22,780 breast cancer cases and 24,181 controls who were recruited in 14 studies conducted in multiple Asian countries (Supplementary Table 1). The discovery stage (stage 1) included 2 GWAS in which 5,285 Chinese women (SBCGS-1) and 4,777 Korean women (SeBCS1) were scanned primarily using Affymetrix Genome-Wide Human SNP Array 6.0, which consists of 906,602 SNPs. After applying quality control filters described previously 6,9,11 , 5,152 Chinese women (2,867 cases and 2,285 controls; 677,157 SNPs) and 4,298 Korean women (2,246 cases and 2,052 controls; 555,117 SNPs) remained in the cur-rent analysis. Imputation was conducted for each study following the MACH algorithm 12 using HapMap 2 release 22 CHB (Han Chinese in Beijing, China) and JPT (Japanese in Tokyo, Japan) data (2,416,663 SNPs) as the reference. Only SNPs with a high imputation quality score (RSQR ≥ 0.50) were analyzed for associations with breast can-cer risk. In the analyses of data from Chinese and Korean women, a total of 1,930,412 and 1,907,146 SNPs, respectively, were included. A meta-analysis of these GWAS data was conducted using a fixed-effects, inverse variance meta-analysis with the METAL program 13 . There was little evidence of inflation in the association test statis-tics for the studies included in stage 1 (genomic inflation factors (λ): λ = 1.0426 for SBCGS-1, λ = 1.0431 for SeBCS1 and λ = 1.0499 for both studies combined; Supplementary Fig. 1). When scaled to a study of 1,000 cases and 1,000 controls, λ 1,000 values were 1.02, 1.02 and 1.01, respectively. To select SNPs for stage 2 replication, we used the following criteria: (i) association P < 0.05 in the stage 1 meta-analysis results; (ii) the
    Nature Genetics 07/2014; · 29.65 Impact Factor
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    ABSTRACT: To date, the association between diabetes mellitus (DM) and gastric cancer has been controversial, including the underlying mechanism. We investigated the association between plasma diabetic biomarkers (insulin, C-peptide, and blood glucose) and gastric cancer risk. In addition, homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β) were calculated. A total of 36,745 subjects aged 40–69 years in the Japan Public Health Center–based prospective study (JPHC) who returned the baseline questionnaire and provided blood samples were followed from 1990 to 2004. In the present analysis, 477 cases and 477 matched controls were used. The odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) for developing gastric cancer were calculated using conditional logistic regression models. Plasma insulin was positively associated with increased risk of gastric cancer; compared to tertile 1, ORs were 1.69 (95% CI = 1.11–2.59) and 2.01 (1.19–3.38) for tertiles 2 and 3, respectively (p for trend = 0.009). In men, C-peptide was also positively associated with a significant risk; corresponding ORs were 1.42 (0.85–2.38) and 1.91 (1.03–3.54), respectively (p for trend = 0.04). These findings were confirmed for blood samples from the fasting group (≥8 h after a meal). Higher HOMA-IR was also associated with increased risk, whereas no association was observed for blood glucose. Our findings suggest that Japanese population with higher insulin and C-peptide levels derived from insulin resistance have an elevated risk of gastric cancer. © 2014 Wiley Periodicals, Inc.
    International Journal of Cancer 07/2014; · 6.20 Impact Factor
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    ABSTRACT: No large population-based prospective study has investigated the risks of suicide and death by other externally caused injuries (ECIs) among stroke patients. The purpose of this study was to examine whether stroke increases the risks of suicide and ECI deaths.
    Psychosomatic medicine. 06/2014;
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    ABSTRACT: Compared with western populations, the consumption of soy foods among Japanese is very high and the incidence of endometrial cancer very low. We evaluated the association of soy food and isoflavone intake with endometrial cancer risk in Japanese women.
    BJOG An International Journal of Obstetrics & Gynaecology 06/2014; · 3.76 Impact Factor
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    ABSTRACT: Background Clarification of the putative etiologic role of heterocyclic aromatic amines (HAAs) in the development of cancer requires a validated assessment tool for dietary HAAs. This study primarily aimed to evaluate the validity of a food frequency questionnaire (FFQ) in estimating HAA intake, using 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) level in human hair as the reference method. Methods We first updated analytical methods of PhIP using liquid chromatography-electrospray ionization/tandem mass spectrometry (LC-ESI/MS/MS) and measured 44 fur samples from nine rats from a feeding study as part-verification of the quantitative performance of LC-ESI/MS/MS. We next measured PhIP level in human hair samples from a validation study of the FFQ (n = 65). HAA intake from the FFQ was estimated using information on intake from six fish items and seven meat items and data on HAA content in each food item. Correlation coefficients between PhIP level in human hair and HAA intake from the FFQ were calculated. Results The animal feeding study of PhIP found a significant dose–response relationship between dosage and PhIP in rat fur. Mean level was 53.8 pg/g hair among subjects with values over the limit of detection (LOD) (n = 57). We found significant positive correlation coefficients between PhIP in human hair and HAA intake from the FFQ, with Spearman rank correlation coefficients of 0.35 for all subjects, 0.21 for subjects with over LOD values, and 0.34 for subjects with over limit of quantification. Conclusion Findings from the validation study suggest that the FFQ is reasonably valid for the assessment of HAA intake.
    Cancer Causes and Control 06/2014; · 2.96 Impact Factor
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    ABSTRACT: While the global methylation level of leukocyte DNA may be a suitable biomarker for cancer risk, the level may be influenced by multiple factors, both environmental and host-related, one of which is exposure to environmental pollutants. To date, three epidemiologic studies have examined associations between serum organochlorine levels and global DNA methylation level, but their findings are not fully consistent, and the associations thus require confirmation in other well-characterized populations. We tested the association between organochlorine exposure and the global DNA methylation level of leukocytes in Japanese women. We conducted a cross-sectional study using the control group of a breast cancer case-control study in Japan. Subjects were 403 Japanese women who provided blood samples. Serum polychlorinated biphenyls (PCBs) and nine pesticide-related organochlorines were measured by gas chromatography isotope-dilution high-resolution mass spectrometry. Further, global methylation level of peripheral leukocyte DNA among 399 women was measured by luminometric methylation assay. Linear trends in the association between methylation and quartile levels of organochlorines were evaluated by regression coefficients in a multivariable linear regression model. We found significant inverse associations between the global methylation level in leukocyte DNA and many of the organochlorine levels measured. Global methylation level was significantly decreased by 0.33-0.83% per quartile category for serum o,p'-dichlorodiphenyltrichloroethane (o,p'-DDT), p,p'-DDT, p,p'-dichlorodiphenyldichloroethylene, trans-nonachlor, oxychlordane, hexachlorobenzene, β-hexachlorocyclohexane, PCB17, PCB52/69, PCB74, PCB114, and PCB183. Serum organochlorine levels were inversely associated with the global methylation level of leukocyte DNA in a relatively large sample of Japanese women.
    Science of The Total Environment 05/2014; 490C:603-609. · 3.16 Impact Factor
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    ABSTRACT: Cyclin B1 is a checkpoint protein that regulates cell division from G2 to the M phase. Studies in mice have shown that cyclin B1 vaccine-induced immunity significantly delayed or prevented the spontaneous cancer development later in life. We hypothesized that if these results showing a protective effect of anti-cyclin B1 antibodies could be extrapolated to the human condition, cancer-free individuals should have higher levels of endogenous antibodies than patients with cancers characterized by the overexpression of this tumor-associated antigen. To test this hypothesis, we characterized a large (1739 subjects) number of multiethnic patients with breast cancer (which overexpresses cyclin B1) and matched controls for anti-cyclin B1 IgG antibodies. Multivariate analyses, after adjusting for the covariates, showed that cancer-free individuals had significantly higher levels of naturally occurring IgG antibodies to cyclin B1 than patients with breast cancer (mean ± SD: 148.0 ± 73.6 vs. 126.1 ± 67.8 arbitrary units per mL; p < 0.0001). These findings may have important implications for cyclin B1-based immunotherapy against breast cancer and many other cyclin B1-overexpressing malignancies.
    Clinical & Experimental Immunology 05/2014; · 3.28 Impact Factor
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    ABSTRACT: Background:Global hypomethylation has been suggested to cause genomic instability and lead to an increased risk of cancer. We examined the association between the global methylation level of peripheral blood leukocyte DNA and breast cancer among Japanese women.Methods:We conducted a hospital-based case-control study of 384 patients aged 20-74 years with newly diagnosed, histologically confirmed invasive breast cancer, and 384 matched controls from medical checkup examinees in Nagano, Japan. Global methylation levels in leukocyte DNA were measured by LUminometric Methylation Assay. Odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between global hypomethylation and breast cancer were estimated using a logistic regression model.Results:Compared with women in the highest tertile of global methylation level, ORs for the second and lowest tertiles were 1.87 (95% CI=1.20-2.91) and 2.86 (95% CI=1.85-4.44), respectively. Global methylation levels were significantly lower in cases than controls, regardless of the hormone receptor status of the cancer (all P values for trend <0.05).Interpretation:These findings suggest that the global methylation level of peripheral blood leukocyte DNA is low in patients with breast cancer and may be a potential biomarker for breast cancer risk.British Journal of Cancer Advance online publication, 1 May 2014 1; doi:10.1038/bjc.2014.223
    British Journal of Cancer 05/2014; · 5.08 Impact Factor
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    ABSTRACT: Objective There have been very few population-based prospective studies that have investigated the risks of deaths by suicide and other externally caused injuries (ECIs) among cancer patients in an Asian population. This study investigated whether the risk of death by both suicide and ECIs increases during the first year following the initial diagnosis of cancer.Methods Data were analyzed from a population-based cohort of Japanese residents between 1990 and 2010, collected during the Japan Public Health Center-based Prospective Study. Poisson regression models were used to calculate adjusted risk ratios (RRs) for both suicide and ECI deaths. To adjust for unmeasured confounding factors, case-crossover analyses were conducted for all patients with cancer who died by suicide and ECIs.ResultsA population-based cohort of 102,843 Japanese residents was established. During the follow-up period, there were 34 suicides and 48 ECI deaths among patients with cancer, as compared with 527 suicides and 707 ECI deaths among those who did not have cancer. Analyses revealed that those who were newly diagnosed with cancer were at a greatly increased risk of death by suicide and ECIs within the first year after their diagnosis (suicide RR = 23.9, 95% CI: 13.8–41.6; ECI RR = 18.8, 95% CI: 11.4–31.0). Furthermore, the case-crossover analyses generally confirmed the results of the Poisson regressions.Conclusions The risks of suicide and ECI deaths within the first year after a cancer diagnosis were higher than those among cancer-free populations. A diagnosis of cancer is a critical experience that may increase the risk of fatal outcomes. Copyright © 2014 John Wiley & Sons, Ltd.
    Psycho-Oncology 04/2014; · 4.04 Impact Factor
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    ABSTRACT: Purpose Cross-sectional studies have shown an association between different coping styles and suicidal behavior. It is unknown whether there is any prospective association between coping behaviors and suicide in the general population. Methods The study population consisted of participants of the Japanese Public Health Center-based prospective study (JPHC Study). In the 10-year follow-up questionnaire, subjects aged 50-79 were asked how they handle daily problems. Coping behaviors were used to determine two coping strategies (approach coping and avoidance coping). Out of 99 439 subjects that returned the 10-year follow-up questionnaire, 70 213 subjects provided complete answers on coping and were included in our analyses. Cox regression models, adjusted for confounders, were used to determine the risk of committing suicide according to coping style. Mean follow-up time was 8.8 years. Results Two coping behaviors were significantly associated with suicide over time: planning (HR=0.64, 95% CI, 0.42, 0.98), and self-blame (HR=2.15, 95% CI, 1.26, 3.68). Of the coping strategies, only the avoidance coping strategy was significantly associated with suicide (HR=2.51, 95% CI, 1.27, 4.95). Conclusions For the first time two coping behaviors and one coping strategy have been shown to have a significant prospective association with suicide in a general population.
    Annals of epidemiology 03/2014; · 2.95 Impact Factor
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    ABSTRACT: A positive association between body mass index (BMI) and breast cancer risk among postmenopausal women has been reported, and a weak inverse association has been suggested among premenopausal women from studies in the Western population. The effects of BMI on breast cancer have remained unclear among the Asian population, especially in premenopausal women. We assessed the associations between BMI and breast cancer incidence by a pooled analysis from eight representative large-scale cohort studies in Japan. Cancer incidence was mainly confirmed through regional population-based cancer registries and/or through active patient notification from major local hospitals. Breast cancer was defined as code C50 according to ICD10. Pooled estimates of the hazard ratios (HRs) and 95% confidence interval (CIs) for breast cancer were calculated using random-effects models. Analytic subjects were 183 940 women, 1783 of whom had breast cancer during 2 194 211 person-years of follow-up. A positive association between BMI and the risk of postmenopausal breast cancer was observed (trend P < 0.001). The HRs for premenopausal breast cancer were 1.05 (95% CI 0.56-1.99), 1.07 (95% CI 0.76-1.52), 0.91 (95% CI 0.64-1.30), 1.15 (95% CI 0.76-1.73), 1.45 (95% CI 0.71-2.94), and 2.25 (95% CI 1.10-4.60), respectively, in BMIs of <19, 19 to <21, 21 to <23, 25 to <27, 27 to <30, and ≥30 kg/m(2). These results were not substantially altered after excluding the patients who were diagnosed with breast cancer in the first 2 years of follow-up. The increased risk of postmenopausal breast cancer among women with higher BMIs was confirmed in Japanese. A borderline-significant positive association between BMI and premenopausal breast cancer was observed, suggesting that body mass in Asian women might have opposite effects on breast cancer compared with Western women.
    Annals of Oncology 02/2014; 25(2):519-24. · 6.58 Impact Factor
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    ABSTRACT: Background:Colorectal cancer (CRC) incidence rate increased rapidly in Japan between the 1950s and 1990s. We examined the association between rice intake and CRC risk in comparison with bread, noodles and cereal among Japanese adults enrolled in the Japan Public Health Center-based prospective Study.Methods:A total of 73 501 Japanese men and women were followed-up from 1995 to 1999 until the end of 2008 for an average of 11 years. During 801 937 person-years of follow-up, we identified 1276 incident cases of CRC. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) of CRC for rice, noodle, bread and cereal intake were calculated by Cox proportional hazards model.Results:Overall, no significant association was observed for the highest quartile of rice intake compared with the lowest and the risk of CRC and its subsites in men (HR, 0.77; 95% CI, 0.56-1.07) and women (HR, 1.10; 95% CI, 0.71-1.68). However, a non-significant inverse trend was observed between rice intake and rectal cancer in men. No clear patterns of association were observed in bread, noodle and cereal intake.Conclusion:Our findings suggest that the consumption of rice does not have a substantial impact on the risk of CRC in the Japanese population.British Journal of Cancer advance online publication, 2 January 2014; doi:10.1038/bjc.2013.799
    British Journal of Cancer 01/2014; · 5.08 Impact Factor
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    ABSTRACT: The genetic basis of sporadic colorectal cancer (CRC) is not well explained by known risk polymorphisms. Here we perform a meta-analysis of two genome-wide association studies in 2,627 cases and 3,797 controls of Japanese ancestry and 1,894 cases and 4,703 controls of African ancestry, to identify genetic variants that contribute to CRC susceptibility. We replicate genome-wide statistically significant associations (P<5 × 10(-8)) in 16,823 cases and 18,211 controls of European ancestry. This study reveals a new pan-ethnic CRC risk locus at 10q25 (rs12241008, intronic to VTI1A; P=1.4 × 10(-9)), providing additional insight into the aetiology of CRC and highlighting the value of association mapping in diverse populations.
    Nature Communications 01/2014; 5:4613. · 10.74 Impact Factor
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    ABSTRACT: In many developed countries, socioeconomic status is associated with cancer incidence and survival. However, research in Japan is sparse. We examined the association between neighborhood deprivation based on the Japanese Deprivation Index and the risk of incidence, mortality and survival from total and major cancers in the Japan Public Health Center-based Prospective Study.
    PLoS ONE 01/2014; 9(9):e106729. · 3.53 Impact Factor

Publication Stats

4k Citations
947.33 Total Impact Points


  • 2004–2014
    • National Cancer Center, Japan
      • • Research Center for Cancer Prevention and Screening
      • • Center for Cancer Control and Information Services
      Edo, Tōkyō, Japan
  • 2013
    • Tokyo Healthcare University
      • Department of Medical Nutrition
      Edo, Tōkyō, Japan
    • Harvard Medical School
      Boston, Massachusetts, United States
    • Juntendo University
      • Department of Epidemiology and Environmental Health
      Edo, Tōkyō, Japan
  • 2012–2013
    • Medical University of South Carolina
      • Department of Microbiology and Immunology (College of Medicine)
      Charleston, SC, United States
    • Osaka City University
      • Department of Public Health
      Ōsaka, Ōsaka, Japan
    • National Institute for Environmental Studies
      • Center for Environmental Health Sciences
      Tsukuba, Ibaraki, Japan
    • Tokyo University of Agriculture
      • Department of Nutrition
      Edo, Tōkyō, Japan
  • 2010–2012
    • Vanderbilt University
      • Division of Epidemiology
      Nashville, MI, United States
    • Aichi Cancer Center
      Ōsaka, Ōsaka, Japan
  • 2008–2012
    • Tokyo Medical and Dental University
      • Department of Molecular Epidemiology
      Edo, Tōkyō, Japan
    • University of Tsukuba
      • Institute of Community Medicine
      Tsukuba, Ibaraki-ken, Japan
    • Tokyo University of Science
      • Department of Management Science
      Edo, Tōkyō, Japan
  • 2011
    • Karolinska Institutet
      • Institutionen för medicinsk epidemiologi och biostatistik
      Solna, Stockholm, Sweden
    • National Center for Global Health and Medicine in Japan
  • 2007–2010
    • Kyorin University
      • Department of Public Health
      Edo, Tōkyō, Japan
    • Tokyo University and Graduate School of Social Welfare
      Edo, Tōkyō, Japan
  • 2009
    • Hokkaido University
      Sapporo, Hokkaidō, Japan
    • Showa University
      • Department of Medicine
      Shinagawa, Tōkyō, Japan
  • 2003–2007
    • National Cancer Research Institute
      Londinium, England, United Kingdom
  • 2002
    • Gunma University
      • Department of Public Health
      Maebashi, Gunma Prefecture, Japan