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Introduction: Smoking cessation has been known to be associated with drinking behaviors, which are influenced by polymorphisms in genes encoding alcohol metabolizing enzymes. The aim was to evaluate the impact of aldehyde dehydrogenase 2 (ALDH2, rs671) and alcohol dehydrogenase 1B (ADH1B, rs1229984) polymorphisms together with drinking behaviors on smoking cessation.Methods: We conducted a cross-sectional study with 1137 former smokers and 1775 current smokers without any cancer at Aichi Cancer Center Hospital between 2001 and 2005. Unconditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for successful smoking cessation by comparing former smokers (quitters) with current smokers (non-quitters).Results: Older age, lower amount of cumulative smoking exposure, lower number of cigarettes per day, younger age of smoking initiation, shorter smoking duration, longer time to first cigarette in the morning, and lower amount of drinking among ever drinkers were predictors of smoking cessation. After careful adjustment for age, sex, smoking patterns, and drinking status, the ORs for smoking cessation among subjects with ALDH2 Glu/Lys and Lys/Lys were 1.02 (95% CI 0.84-1.23) and 1.78 (95% CI 1.23-2.58) compared with those with ALDH2 Glu/Glu, respectively Mediation analyses confirmed that the effect of ALDH2 Lys/Lys on smoking cessation was independent by dinking behaviors. No statistically significant association between ADH1B polymorphism and smoking cessation was observed.Conclusions: In our Japanese population, ALDH2 polymorphism predicts smoking cessation, independent by drinking behaviors. Interventions for promoting smoking cessation by ALDH2 polymorphism may be useful in Asian populations.Implications: We newly show that subjects with ALDH2 Lys/Lys genotype in a functional polymorphism, rs671, are more likely to quit smoking than those with ALDH2 Glu allele in a Japanese population. Our finding suggests that ALDH2 polymorphism may be useful for promoting smoking cessation in those specific populations as East Asian ones with frequent ALDH2 Lys allele carriers. [ABSTRACT FROM AUTHOR]

Over the past 20 years, high-penetrance pathogenic mutations in genes BRCA1, BRCA2, TP53, PTEN, STK11 and CDH1 and moderate-penetrance mutations in genes CHEK2, ATM, BRIP1, PALB2, RAD51C, RAD50 and NBN have been identified for breast cancer. In this study, we investigated whether there are additional variants in these 13 genes associated with breast cancer among women of Asian ancestry. We analyzed up to 654 single nucleotide polymorphisms (SNPs) from 6269 cases and 6624 controls of Asian descent included in the Breast Cancer Association Consortium (BCAC), and up to 236 SNPs from 5794 cases and 5529 controls included in the Shanghai Breast Cancer Genetics Study (SBCGS). We found three missense variants with minor allele frequency (MAF) <0.05: rs80358978 (Gly2508Ser), rs80359065 (Lys2729Asn) and rs11571653 (Met784Val) in the BRCA2 gene, showing statistically signifcant associations with breast cancer risk, with P-values of 1.2 x 10-4, 1.0 x 10-3 and 5.0 x 10-3, respectively. In addition, we found four low-frequency variants (rs8176085, rs799923, rs8176173 and rs8176258) in the BRCA1 gene, one common variant in the CHEK2 gene (rs9620817), and one common variant in the PALB2 gene (rs13330119) associated with breast cancer risk at P < 0.01. Our study identified several new risk variants in BRCA1, BRCA2, CHEK2, and PALB2 genes in relation to breast cancer risk in Asian women. These results provide further insights that, in addition to the high/moderate penetrance mutations, other low-penetrance variants in these genes may also contribute to breast cancer risk. [ABSTRACT FROM AUTHOR]

Although a range of chemical exposures (cigarette smoking and occupational exposure) are recognized risk factors for the development of bladder cancer (BCa), many epidemiological studies have demonstrated that alcohol drinking is not associated with BCa risk. Aldehyde dehydrogenase 2 (ALDH2; rs671, Glu504Lys) and alcohol dehydrogenase 1B (ADH1B; rs1229984, His47Arg) polymorphisms impact the accumulation of acetaldehyde, resulting in an increased risk of various cancers. To date, however, no studies evaluating the association between BCa risk and alcohol drinking have considered these polymorphisms. Here, we conducted a matched case-control study to investigate whether ALDH2 and ADH1B polymorphisms influence BCa risk associated with alcohol drinking. Cases were 74 BCa patients and controls were 740 first-visit outpatients without cancer at Aichi Cancer Center Hospital between January 2001 and December 2005. Odds ratio (OR), 95% confidence interval (CI) and gene-environment interaction were assessed by conditional logistic regression analysis with adjustment for potential confounders. Results showed that ALDH2 Glu/Lys was associated with a significantly increased risk of BCa compared with Glu/Glu (OR 2.03, 95% CI 1.14-3.62, P = 0.017). In contrast, ALDH2 Glu/Lys showed no increase in risk among the stratum of never drinkers compared with Glu/Glu, indicating a gene-environment interaction. ADH1B His/Arg had an OR of 1.98 (1.20-3.24, P = 0.007) compared with His/His. ADH1B Arg+ showed a similar OR and 95% CI. Individuals with ALDH2 Glu/Lys and ADH1B Arg+ had the highest risk of BCa compared with ALDH2 Glu/Glu and ADH1B His/ His [OR 4.00 (1.81-8.87), P = 0.001]. [ABSTRACT FROM AUTHOR]

Purpose. Although the impact of imatinib in improving survival outcomes in chronic myelogenous leukemia (CML) patients has been widely reported, its impact on mortality from CML has not been evaluated. A survival benefit demonstrated in clinical trials does not simply translate to a decrease in mortality. To evaluate the impact of imatinib on the public health, we estimated the age-standardized mortality rate of CML patients in Japan and the U.S. using vital statistics data for Japan and data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute for the U.S. Patients and Methods. The period covered in this analysis is 1993-2008, during which 64,203 patients in Japan and 26,888 patients in nine registries in the U.S. died as a result of CML. We used joinpoint regression analysis to evaluate the significance of trends in mortality. Results. Estimated age-standardized mortality rates decreased significantly in both countries after the availability of imatinib. The annual percent changes (95% confidence interval) in the U.S. were -12.3% (-14.8% to -9.7%) for men and -11.6% (-13.1% to -10.1%) for women. In Japan, these were -20.8% (-36.2% to -1.6%) for men and -15.6% (-18.8% to -12.2%) for women. The period of change in the mortality trend seems to correlate with the period in which imatinib appeared in the two countries. The CML mortality rate in 2008 was nearly 30% that of the 1993 level. Conclusion. This is one example of the advent of a single new drug changing the picture of a single disease, CML. These results may encourage further development of drugs based on the concept of molecular targeting. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (H. pylori) is a causative agent for peptic ulcers as well as some types of gastric lymphoma; however, the relationship between a peptic ulcer history in combination with H. pylori infection and the risk of gastric lymphoma has not been fully evaluated. To examine this point, we conducted a case-control study with 645 patients histologically diagnosed as having malignant lymphomas and 3225 non-cancer controls. Plasma H. pylori IgG status was assessed for subgroups for which blood samples were available (116 cases and 114 controls). An association with a history of gastric, but not duodenal ulcers was found for gastric lymphoma [odds ratio (OR) = 5.41, 95% confidence interval (CI): 3.12–9.39]. In the examination according to histological subtype, the OR was high for both gastric mucous-associated lymphoid tissue (MALT) lymphoma (OR = 5.54, 95% CI: 2.56–12.01) and diffuse large B-cell lymphoma (DLBCL) (OR = 7.23, 95% CI: 2.62–19.90). In the analysis of H. pylori antibody, the risk of total gastric lymphoma was associated with H. pylori infection (OR = 5.34, 95% CI: 1.42–20.05). A high prevalence of H. pylori infection was also found for both gastric MALT lymphoma (8 out of 10: 80.0%) and DLBCL (8 out of 9: 88.9%). Further, in subgroup analysis of subjects with H. pylori infection, gastric ulcer history, but not duodenal ulcer history was associated with the risk of gastric lymphoma (OR = 4.15, 95% CI: 1.02–16.89). In conclusion, we found a positive association with a past history of gastric ulcer and H. pylori infection for gastric lymphoma, while duodenal ulcer history was no association. These results suggested the risk of gastric lymphoma increased by interaction between H. pylori infection and gastric ulcer history. Further studies are warranted. [ABSTRACT FROM AUTHOR]

Alcohol consumption is recognized as a potential risk factor for colorectal cancer (CRC). Genetic polymorphisms, aldehyde dehydrogenase (ALDH2) Glu487Lys and alcohol dehydrogenase 2 (ADH2) His47Arg, which have a strong impact on alcohol metabolism, are common in Japanese population but their significance for CRC carcinogenesis remains to be clarified in detail. We, therefore, conducted a matched case–control study with 257 incident CRC cases and 771 non-cancer controls at Aichi Cancer Center, including analysis of interactions between polymorphisms, drinking and folate consumption. The ADH2 Arg allele was found to be associated with increased risk, the odds ratios (ORs) being 1.35 (95% confidence interval: 1.00–1.84) and 1.93 (1.06–3.53) for the His/Arg and Arg/Arg genotypes, respectively. In contrast, no apparent links were observed with the ALDH2 genotypes. Individuals having ALDH2 Glu/Glu with ADH2 Arg+, ALDH2 Lys+ with ADH2 His/His and ALDH2 Lys+ with ADH2 Arg+ showed ORs of 0.10(0.04–0.21), 0.10 (0.06–0.19) and 1.36 (0.94–1.97), respectively, compared with ALDH2 Glu/Glu with ADH2 His/His. Statistical gene–gene interaction was significant between the two polymorphisms for the risk of CRC (P< 0.001). The impact of ALDH2 Lys+ with ADH2 Arg+ was more evident in low folate consumer (OR = 2.32, 1.19–4.55) than high folate consumer (OR 1.38, 0.80–2.38). In conclusion, while we failed to find any significant association with the ALDH2 polymorphism itself, significant interaction between ALDH2 and ADH2 polymorphism was observed. Replication in the future study is warranted. [ABSTRACT FROM AUTHOR]

One-carbon metabolism, in which folate plays an essential role, is involved in DNA methylation and synthesis, and is suspected of impacting on colorectal carcinogenesis. Alcohol is well recognized as a risk factor for colorectal cancer (CRC) and interactions with one-carbon metabolism have also been suggested. Therefore, functional polymorphisms in genes encoding members of this pathway, MTHFR C677T and A1298C (genes for methylenetetrahydrofolate reductase), MTR A2756G (gene for methionine synthase) and TS (gene for thymidylate synthase) tandem repeats polymorphisms, have attracted attention. We conducted a matched case–control study with 257 incident CRC cases and 771 non-cancer controls at the Aichi Cancer Center to clarify associations among folate intake and four polymorphisms with reference to CRC risk. Gene–environment interaction between polymorphisms, drinking and folate consumption was also evaluated. None of the polymorphisms showed any significant impact on CRC risk by genotype alone, but when combined with alcohol consumption the MTHFR 677CC type showed a significantly reduced risk (odds ratio (OR) = 0.45, 95% confidence interval (CI): 0.23–0.86) (P = 0.01). MTR GG showed increased risk only among drinkers (OR = 3.35, 1.40–8.05) (P = 0.047). TS polymorphism did not show statistical significance by genotype alone, while interaction with drinking was significant (P = 0.028). The association was not changed even after stratification by daily folate consumption and drinking habit. In conclusion, we found consistently significant interactions between one-carbon metabolism-related polymorphisms and alcohol drinking. [ABSTRACT FROM AUTHOR]

Folate takes part in two biological pathways involved in DNA methylation and synthesis, and a potential protective influence of this nutrient chemical against carcinogenicity has been recognized in several sites, including the esophagus. Therefore, the functional polymorphisms in genes encoding folate metabolizing enzymes, MTHFR C677T and MTR A2756G, might be suspected of impacting on esophageal cancer risk. We therefore conducted a matched case–control study of 165 esophageal cancer cases and 495 non-cancer controls to clarify associations among folate intake, MTHFR C677T and MTR A2756G polymorphisms, and esophageal cancer risk. Gene–environment interactions between the two polymorphisms, and drinking and smoking were also evaluated. Folate consumption and MTHFR 677TT were associated with a non-significant tendency for decreased risk while the MTR genotypes did not show any links in themselves; further, when analysis was limited to heavy drinkers, the MTHFR TT genotype significantly decreased esophageal cancer risk [odds ratio (OR) = 0.27, 95% confidence interval (CI), 0.09–0.76]. The OR for the gene–environment interaction between heavy drinking and the 677TT genotype in the case-only design was 0.31 (95% CI, 0.10–0.94), indicating risk with heavy drinking to be 69% decreased in individuals harboring the 677TT genotype. We failed to find any significant interaction between either of the polymorphisms and smoking. [ABSTRACT FROM AUTHOR]

APE1 (apurinic/apyrimidinic endonuclease 1) and XRCC1 (X-ray cross-complementing group 1) are DNA repair proteins that play important roles in the base excision repair (BER) pathway. Polymorphisms in their encoding genes are associated with altered DNA repair capacity and thus may impact on cancer risk. In the present case-control study with 178 Japanese incident lung cancer cases and 449 age- and sex-matched controls, we investigated the gene–environment interaction among APE1 Asp148Glu, XRCC1 Arg399Gln and smoking habit in lung cancer risk. The results were analyzed by using conditional logistic regression models, adjusted for age, sex and smoking status. The adjusted odds ratio for the current smokers with APE1 148Asp/Asp, Asp/Glu and Glu/Glu genotype as compared with the never smokers with the Asp/Asp genotype were 3.01 (95% CI 1.39–6.51, P = 0.005), 2.73 (95% CI 1.29–5.77, P = 0.008) and 7.33 (95% CI 2.93–18.3, P < 0.001), respectively. The gene–environment interaction between current smoking and APE1 148Glu/Glu genotype was statistically significant (OR 3.59, 95% CI 1.28–10.1, P = 0.015). When APE1 Asp148Glu and XRCC1 Arg399Gln polymorphisms were evaluated together, the adjusted odds ratios for the current smokers with 0–1, 2 and 3–4 of APE1 148Glu or XRCC1 399Gln alleles as compared with never smokers with the 0 of these alleles were 2.96 (95% CI 1.57–5.58, P = 0.001), 3.86 (95% CI 1.85–8.05, P < 0.001) and 6.01 (95% CI 2.25–16.1, P < 0.001), respectively. The gene–environment interaction between current smoking and three or more APE1 148Glu or XRCC1 399Gln alleles was statistically significant (OR 2.44, 95% CI 1.00–9.22, P = 0.049). The OR for the gene–environment interaction of Glu/Glu genotype of APE1 codon 148 with heavy smoking was 1.04 (95% CI 0.38–2.90, P = 0.936) and that with light smoking was 2.67 (95% CI 1.00–7.68, P = 0.049). These results suggest that APE1 Asp148Glu and XRCC1 Arg399Gln polymorphisms might modify the risk of lung cancer attributable to cigarette smoking exposure. [ABSTRACT FROM AUTHOR]