Meat consumption,cigarette smoking,and genetic susceptibility in the etiology of colorectal cancer: results from a Dutch prospective study

Objective: We evaluated the effect of meat consumption and cigarette smoking in combination with N-acetyltransferases 1 and 2 (NAT1 and NAT2), and glutathione S-transferase M1 (GSTM1) genotypes on colorectal cancer. Methods: From a Dutch prospective study, after 8.5 years of follow-up, data of 102 incident colorectal cancer cases and a random sample of 537 controls frequency-matched for gender and age were analyzed. Baseline information on dietary and smoking habits, as well as blood samples for DNA isolation and genotyping, were available. Results: Red meat intake increased colorectal cancer risk among men (OR 2.7; 95% CI 1.1–6.7 highest vs. lowest intake), whereas poultry and fish decreased risk among women (OR 0.5; 95% CI 0.2–1.07). Cigarette smoking for at least 16 years increased colorectal cancer risk among former smokers only (OR 2.7; 95% CI 1.0–7.4), compared to those having smoked for 15 years or less. NAT1 and NAT2 polymorphisms did not significantly modify these associations. High consumption of poultry and fish was inversely associated with colorectal cancer only in the presence of GSTM1. Conclusions: In this study meat consumption and former long-term smoking were associated with colorectal cancer. Associations of colorectal cancer with different types of meat were modified by gender and GSTM1 genotype.     

Cigarette Smoking, Alcohol Consumption, and Endometrial Cancer Risk: A Population-based Study in Sweden

Objective: To assess effects of cigarette smoking and alcohol consumption on the risk of endometrial cancer among postmenopausal women. Methods: We performed a nationwide population-based case–control study among postmenopausal women aged 50–74 years in Sweden, including 709 incident endometrial cancer cases and 3368 controls. Results: Compared to never smokers, recent/current smokers had a decreased risk of endometrial cancer (multivariate OR 0.61, 95% CI 0.47–0.80), but former smokers presented no substantial difference in risk (multivariate OR 0.90, 95% CI 0.72–1.14). We observed a decreased risk of endometrial cancer for postmenopausal smoking, but there was no clear impact on risk for premenopausal smoking. The inverse association of smoking with risk was not explained by differences in body mass index between smokers and nonsmokers. Alcohol consumption was not clearly associated with risk of endometrial cancer. The multivariate OR for women consuming up to 1.6 g of alcohol per day was 1.12 (95% CI 0.88–1.44), and 0.92 (95% CI 0.70–1.20) for women consuming more than 4 g per day (p for trend over categories=0.44). Conclusions: Current cigarette smoking reduces the risk of postmenopausal endometrial cancer, but the inverse association dissipates after smoking cessation. Premenopausal smoking might not affect risk of postmenopausal endometrial cancer. Alcohol consumption is not materially associated with risk.     

Alcohol Dehydrogenase 3, Glutathione S-transferase M1 and T1 Polymorphisms, Alcohol Consumption and Hepatocellular Carcinoma (Italy)

Objective: The aim of this study was to investigate the role of alcohol dehydrogenase type 3 (ADH3), glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) polymorphisms in modifying hepatocellular carcinoma (HCC) risk according to alcohol intake.Methods: A hospital-based case–control study was conducted in two areas of North Italy. Two-hundred cases hospitalized for HCC and 400 controls were recruited. Genotypes were determined using PCR and the PCR/restriction fragment length polymorphism-based method.Results: There was no association of the putative risk genotypes ADH3^1-1, GSTM1 null and GSTT1 null with HCC (odds ratio [OR], 0.8; 95% confidence interval [CI], 0.5–1.3; OR, 1.0; 95% CI, 0.6–1.5; OR, 0.8; 95% CI, 0.4–1.4, respectively). A steady increase in HCC risk with increasing alcohol intake, which did not vary according to ADH3 and GSTT1 genotypes, was observed. Nevertheless, the OR for HCC due to an alcohol intake of >100 g of ethanol per day increased in subjects with GSTM1 null genotype (OR, 8.5; 95% CI, 3.9–18.6) compared to GSTM1 non-null genotype (OR, 4.5; 95% CI, 2.0–10.0).Conclusions: ADH3^1-1 and GSTT1 null genotypes did not modify the risk of HCC due to alcohol intake whereas an influence of GSTM1 null genotype for high ethanol consumption was suggested.     

GSTM1 and GSTT1 Polymorphisms, Cigarette Smoking, and Risk of Colon Cancer: A Population-based Case-control Study in North Carolina (United States)

Cigarette smoke is a risk factor for colon cancer, but the importance of dose and interaction with genetic susceptibility remain poorly understood. We used data from a population-based case control study, to examine the association between cigarette smoking and colon cancer in African Americans and whites, and colon cancer and polymorphisms in GSTM1 and GSTT1. A total of 554 cases of primary colon cancer and 874 controls were included in this analysis. We found no association between cigarette smoking (ever versus never) and colon cancer in African Americans (odds ratio (OR)=0.93, 95% confidence interval (CI)=0.65–1.33). In contrast, there was an increased risk of cigarette smoking in whites (OR=1.43, CI=1.05–1.94). There was a small increased risk of colon cancer for individuals with GSTM1 null (African Americans, OR=1.43, CI, 0.98–2.09; whites, OR=1.19, CI, 0.90–1.58) and a decreased risk of colon cancer for individuals with GSTT1 null (African Americans, OR=0.59, CI: 0.40–0.86; whites, OR=0.72, CI: 0.53–1.00). There were weak interactions between GSTT1 null and cigarette smoking in whites, and GSTM1 null genotype and cigarette smoking in African Americans. GSTT1 and GSTM1 polymorphisms may be weakly related to colon cancer risk and there may be racial differences in gene-smoking interactions.     

<Emphasis Type="BoldItalic">BAP1</Emphasis> and Breast Cancer Risk

BAP1 whose protein interacts with BRCA1 was analysed in a series of 47 French familial breast cancer cases negatively tested for BRCA1/2 mutations. The lack of detection of deleterious mutations suggests that BAP1 is not a high risk breast cancer predisposing gene. However, a common identified variant, rs123602, may be tested in sporadic cases as candidate for moderate risk.     

Cigarette smoking,glutathione-s-transferase M1 and t1 genetic polymorphisms,and breast cancer risk (United States)

Objective: It has been suggested that functional polymorphisms in genes encoding tobacco carcinogen-metabolizing enzymes may modify the relationship between tobacco smoking and breast cancer risk. We sought to determine if there is a gene–environment interaction between GSTM1 (GSTM1A and GSTM1B), and GSTT1 genotypes and cigarette smoking in the risk of breast cancer. Methods: Cases and controls were recruited in a case–control study conducted in Connecticut from 1994 to 1998. Cases were histologically confirmed, incident breast cancer patients, and controls were randomly selected from women histologically confirmed to be without breast cancer. A total of 338 cases and 345 controls were genotyped for GSTM1 and GSTT1. Results: None of the GSTM1 genotypes, either alone or in combination with cigarette smoking, was associated with breast cancer risk. There was, however, a significantly increased risk of breast cancer among postmenopausal women with a GSTT1 null genotype (OR = 1.9, 95% CI 1.2–2.9). There were also indications of increased risk of breast cancer associated with cigarette smoking for postmenopausal women with GSTT1-null genotype, especially for those who commenced smoking before age 18 (OR = 2.9, 95% CI 1.0–8.8). Conclusion: Women with a GSTT1-null genotype may have an increased breast cancer risk, especially postmenopausal women who started smoking at younger ages.     

Meat and Fish Consumption, APCGene Mutations and hMLH1 Expression in Colon and Rectal Cancer: a Prospective Cohort Study (The Netherlands)

Objective:The aim of this study was to investigate the associations between meat and fish consumption and APC mutation status and hMLH1 expression in colon and rectal cancer. Methods:The associations were investigated in the Netherlands Cohort Study, and included 434 colon and 154 rectal cancer patients on whom case-cohort analyses (subcohort n = 2948) were performed. Results:Total meat consumption was not associated with the endpoints studied. Meat product (i.e. processed meat) consumption showed a positive association with colon tumours harbouring a truncating APC mutation, whereas beef consumption was associated with an increased risk of colon tumours without a truncating APC mutation (incidence rate ratio (RR) highest versus lowest quartile of intake 1.61, 95% confidence interval (CI) 0.96–2.71, p-trend = 0.04 and 1.58, 95% CI 1.10–2.25, p-trend = 0.01, respectively). Consumption of other meat (horsemeat, lamb, mutton, frankfurters and deep-fried meat rolls) was associated with an increased risk of rectal cancer without a truncating APC mutation (RR intake versus no intake 1.79, 95% CI 1.10–2.90). No associations were observed for meat consumption and tumours lacking hMLH1 expression. Conclusions:Our data indicate that several types of meat may contribute differently to the aetiology of colon and rectal cancer, depending on APC mutation status but not hMLH1 expression of the tumour.     

Glutathione-S-transferase M1, T1 and P1 polymorphisms, and breast cancer risk, in BRCA1/2 mutation carriers

Variation in penetrance estimates for BRCA1/2 carriers suggests that other environmental and genetic factors may modify cancer risk in carriers. The GSTM1, T1 and P1 isoenzymes are involved in metabolism of environmental carcinogens. The GSTM1 and GSTT1 gene is absent in a substantial proportion of the population. In GSTP1, a single-nucleotide polymorphism that translates to Ile112Val was associated with lower activity. We studied the effect of these polymorphisms on breast cancer (BC) risk in BRCA1/2 carriers. A population of 320 BRCA1/2 carriers were genotyped; of them 262 were carriers of one of the three Ashkenazi founder mutations. Two hundred and eleven were affected with BC (20 also with ovarian cancer (OC)) and 109 were unaffected with BC (39 of them had OC). Risk analyses were conducted using Cox proportional hazard models adjusted for origin (Ashkenazi vs non-Ashkenazi). We found an estimated BC HR of 0.89 (95% CI 0.65-1.12, P=0.25) and 1.11 (95% CI 0.81-1.52, P=0.53) for the null alleles of GSTM1 and GSTT1, respectively. For GSTP1, HR for BC was 1.36 (95% CI 1.02-1.81, P=0.04) for individuals with Ile/Val, and 2.00 (95% CI 1.18-3.38) for carriers of the Val/Val genotype (P=0.01). An HR of 3.20 (95% CI 1.26-8.09, P=0.01), and younger age at BC onset (P=0.2), were found among Val/Val, BRCA2 carriers, but not among BRCA1 carriers. In conclusion, our results indicate significantly elevated risk for BC in carriers of BRCA2 mutations with GSTP1-Val allele with dosage effect, as implicated by higher risk in homozygous Val carriers. The GSTM1- and GSTT1-null allele did not seem to have a major effect.     

GSTM1 and GSTT1 Genetic Polymorphisms and Breast Cancer Risk in Selected Filipino Cases

Background: The association of genetic polymorphisms with cancer development has been shown to be race- andtumor site-specific. Thus, this study aimed to determine whether polymorphisms in the GSTM1 and GSTT1 genesare associated with breast cancer among selected Filipinos. Methods: A total of 136 histologically confirmed breastcancer cases were age- and sex-matched with 136 clinically healthy controls. Genomic DNA extracted from bloodsamples of participants were screened for GSTM1 and GSTT1 genetic polymorphisms by multiplex PCR. Results:The frequency of null genotypes among the cases (GSTM1: n=78; 57.4%; GSTT1: n=61; 44.9%) was not significantlydifferent (p>0.05) from the controls (GSTM1: n=93; 68.4%; GSTT1: n=59; 43.4%). It was also demonstrated that riskfor breast cancer was increased in passive smokers carrying the GSTM1 null (OR=2.56; 95% CI=1.38-4.75) or GSTT1positive (OR=2.00; 95% CI=1.05-3.83) genotypes. Moreover, risk was decreased in alcohol users carrying the GSTT1null (OR=0.39; 95% CI=0.16-0.97) genotype. Conclusion: This study suggests that variants of GSTM1 and GSTT1may not be risk factors for breast cancer development among Filipinos. However, the risk may be increased when thesegenotypes were combined with lifestyle or environmental factors.     

Rapid N-acetyltransferase 2 imputed phenotype and smoking may increase risk of colorectal cancer in women (Netherlands)

Objective: The relationship between smoking and colorectal cancer risk and whether such effect is modified by variations in the NAT2 genotype is investigated. Methods: In the prospective DOM (Diagnostisch Onderzoek Mammacarcinoom; 27,722 women) cohort follow-up from 1976 until 1987 revealed 54 deaths due to colon or rectal cancer, and follow-up from 1987 to 01-01-1996 revealed 204 incident colorectal cancer cases. A random sample (n = 857) from the baseline cohort was used as controls. Four NAT2 restriction fragment length polymorphisms (RFLPs) were analysed using DNA extracted from urine samples. Rapid or slow acetylator phenotype status was attributed to individuals. Results: Smoking may increase the risk for colon cancer (RR = 1.36, 95% CI 0.97–1.92) as well as for rectal cancer (RR = 1.31, 95% CI 0.76–2.25), although not statistically significant. Rapid NAT2 acetylation did not increase colorectal cancer risk, but in combination with smoking the risk was statistically significant increased, compared to women who had a slow NAT2 imputed phenotype and never smoked (RR = 1.56, 95% CI 1.03–2.37). For colon cancer, but not for rectal cancer the increased risk was statistically significant (RR = 1.67, 95% CI, 1.05–2.67 versus RR = 1.30 95% CI 0.63–2.68). Conclusions: Our study points to smoking as a risk factor for colon and rectal cancer and, in addition, especially in women with rapid NAT2 imputed phenotype.     

Menopausal hormone therapy use and breast cancer risk in Australia: Findings from the New South Wales Cancer,Lifestyle and Evaluation of Risk study

Randomised controlled trials and large‐scale observational studies have found that current use of menopausal hormone therapy (MHT) is associated with an increased risk of breast cancer; this risk is higher for oestrogen–progestagen combination therapy than for oestrogen‐only therapy. Our study was designed to estimate MHT‐associated breast cancer risk in a population of Australian women. Data were analysed for postmenopausal women with self‐reported incident invasive breast cancer (n = 1,236) and cancer‐free controls (n = 862), recruited between 2006 and 2014 into a large case–control study for all cancer types, the NSW CLEAR study. Information on past and current MHT use was collected from all participants, along with other lifestyle and demographic factors, using a self‐administered questionnaire. Unmatched multivariable logistic regression was performed, adjusting for socio‐demographic, reproductive and health behaviour variables, body mass index and breast screening history. Compared to never users of MHT, the adjusted odds ratio (aOR) for breast cancer in current users of any type of MHT was 2.09 (95% CI: 1.57–2.78; p < 0.0001) and for past users of any type of MHT was 1.03 (0.82–1.28; p = 0.8243). For current users of oestrogen‐only and oestrogen–progestagen therapy, aORs were 1.80 (1.21–2.68; p = 0.0039) and 2.62 (1.56–4.38; p = 0.0003), respectively. These findings are consistent with those from other international observational studies, that current, but not past, use of MHT is associated with a substantially increased risk of breast cancer.     

Glutathione-S-transferase (GSTM1, GSTT1) Null Phenotypes and Risk of Lung Cancer in a Korean Population

Purpose: The aim of this study was to evaluate any association of GSTM1 and GSTT1 null genotypes withthe risk of lung cancer in a South Korean population. Methods: We conducted a large-scale, population-basedcase-control study including 3,933 lung cancer cases and 1,699 controls. Genotypes of GSTM1 and GSTT1 weredetermined using real-time polymerase chain reaction. Results: In logistic regression analysis adjusted for age andsmoking, we did not find any association between GSTM1 or GSTT1 and LC risk in women. However, in men,the GSTM1 and GSTTI null genotypes were borderline associated with risk (OR=1.18, 95% CI=0.99-1.41 forGSTM1, OR=1.18, 95% CI=0.99-1.41 for GSTT1), and combined GSTM1 and GSTT1 null genotypes conferredan increased risk for LC in men (OR=1.39, 95% CI=1.08–1.78). The OR for the GSTT1 null genotype was greaterin subjects aged 55 years old or younger (OR=1.45, 95% CI=1.09-1.92 for men; OR=1.36, 95% CI=0.97–1.90for women), than in those over age 55 (OR=1.03, 95% CI=0.83-1.27 for men; OR=0.86, 95% CI=0.66–1.12 forwomen) in both genders (p for interaction <0.05). Conclusions: In the Korean population, the GSTM1 andGSTT1 null genotypes are risk factors for LC in men; the GSTT1 null genotype has a more prominent effecton LC risk in younger people (age 55 years and under) than in older individuals.     

Prospective study of plasma enterolactone and prostate cancer risk (Sweden)

Objectives: Enterolactone, a phytoestrogen produced by the intestinal microflora from precursors in plant foods, has been postulated to protect against hormone-dependent cancers. We studied the association between plasma enterolactone and risk of prostate cancer. Methods: In the Northern Sweden Health and Disease Cohort, enterolactone concentrations were measured by time-resolved fluoroimmunoassay in plasma taken from 265 men who were diagnosed with prostate cancer at a mean time of 5 years after blood collection, and in plasma from 525 control men, matched for age and date of blood collection. Results: There was no significant association between quartiles of plasma enterolactone and risk of prostate cancer. Odds ratios for prostate cancer, estimated by conditional logistic regression for increasing concentrations of enterolactone in quartiles were 1.00 (referent), 0.81 (95% confidence interval 0.52–1.27), 1.03 (0.67–1.58), and 1.22 (0.80–1.86). Adjustments for body mass index (BMI), smoking status and stratification for age, lag time, storage time and tumour characteristics did not materially alter risk estimates. Men with very low enterolactone levels, however, had significantly higher risk of prostate cancer, odds ratio for bottom decile versus all other deciles was 1.68 (1.03–2.74). Conclusions: Our results do not support the hypothesis that enterolactone formed from dietary lignans protects against prostate cancer.     

Antibiotic exposure and breast cancer in New Zealand

Summary Aims To investigate the hypothesis that use of antibiotics is related to subsequent development of breast cancer and also to apply this theory to other cancer types. Materials and methods A nested case–control study was conducted, using data linkage between the RNZCGP Research Unit database and the New Zealand Hospital Separation Diagnosis database. Cancer related hospital admissions were identified between 1998 and 2002, and prior antibiotic exposure in these patients was then found.Results A total of 6678 patients were identified with a newly diagnosed cancer in this time period. A slightly increased odds ratio (OR) (95% CI) for breast cancer was seen with penicillin, 1.07 (1.02–1.13). Penicillin was also associated with an increased OR with lung and respiratory cancer, 1.13 (1.06–1.21), and skin neoplasms, 1.05 (1.02–1.08). Significant associations were seen between macrolides and leukaemia, 1.15 (1.01–1.30), lung and respiratory cancers, 1.23 (1.10–1.38) and non-Hodgkin’s lymphoma, 1.26 (1.02–1.55). Tetracyclines were significantly associated with non-Hodgkin’s lymphoma, 1.12 (1.01–1.24). Cephalosporins only showed a significant association with leukaemia, 1.35 (1.06–1.71), sulphonamides with colorectal cancers, 1.12 (1.01–1.24), and ‘other‘ antibiotic classes with bladder and renal cancers, 1.34 (1.07–1.67). Conclusions It is most likely that antibiotic exposure represents a confounding factor rather than a causation for breast cancer and other cancer types.     

Glycemic Load,Glycemic Index,and the Risk of Breast Cancer Among Mexican Women

Objective: The amount and composition of dietary carbohydrates is a major determinant of postprandial blood glucose and insulin, and risk of breast cancer has been positively associated with plasma levels of insulin and insulin-like growth factor 1. We sought to evaluate dietary glycemic load (GL) and overall glycemic index (GI) in relation to breast cancer risk in Mexican women. Methods: We examined dietary GL and overall GI and breast cancer risk among 475 women with histologically-confirmed breast cancer and a random sample of 1391 women from Mexico City households. Diet was assessed using a food frequency questionnaire adapted to the Mexican population. Results: The multivariate adjusted or for all women comparing the highest quartile of dietary GL with the lowest quartile was 1.62 (95% CI 1.13–2.32; p-test for trend = 0.02) with a significant trend. In postmenopausal women, the multivariate adjusted or comparing the extreme quartiles was 2.18 (95% CI 1.34–3.55; p-test for trend=0.005). Overall GI was not significantly associated with risk of breast cancer. Conclusion: High intake of rapidly absorbed carbohydrate appears to play an important role in the risk of breast cancer in Mexican women.     

Combined effect of GSTM1, GSTT1, and COMT genotypes in individual

Our previous studies suggested that both catechol O-methyl transferase (COMT) and glutathione S-transferase (GST) M1 and T1 genotypes are associated with breast cancer risk. Here we extended the studies to evaluate the potential combined effect of these genotypes in individual breast cancer risk. Incident breast cancer cases (n = 202) and controls (n = 299) with no previous cancer were recruited from three teaching hospitals in Seoul in 1996-1999. Information on putative risk factors was collected by interviewed questionnaire. PCR-based methods were used for the genotyping analyses. Odds ratios (ORs) and 95% confidence (CIs) intervals were estimated by unconditional logistic regression after adjustment for known or suspected risk factors of breast cancer. Among pre-menopausal women the low activity associated (COMT *L) allele containing genotypes and the GSTM1 null genotype posed increased risks of breast cancer with ORs of 1.7 (95% CI = 1.0 - 2.8) and 1.7 (95% CI = 1.0-2.8), respectively. A marginally significant effect of GSTT1 null genotype was also observed when the total study population was considered (OR = 1.3, 95% CI = 1.0-2.1). When the combined genotype effects were examined, the concurrent lack of GSTM1 and GSTT1 genes posed a more than 2-fold risk of breast cancer (OR = 2.2, 95% CI = 1.2-3.9); this effect was mainly attributable in pre-menopausal women (OR = 3.2, 95% CI = 1.5-7.2). Moreover, the breast cancer risk increased in parallel with the number of COMT, GSTM1, and GSTT1 at-risk genotypes (p for trend = 0.003). This association was particularly clear in pre-menopausal women among whom combination of all three high-risk genotypes posed a 4.1-fold breast cancer risk (95% CI = 1.4-12.7) compared with pre-menopausal women without at-risk genotypes (p for trend = 0.001). The trend was more pronounced in women with BMI greater than 22 kg/m² (p for trend<0.001) and high-risk status of parity factor (nulliparous or women with the first full term pregnancy at age of over 25-year-old) (p for trend = 0.013). These results suggest the combined effect between reproductive factors and GSTM1, GSTT1 andCOMT genotypes in human breast carcinogenesis.     

Association of NAT2 and smoking in relation to breast cancer incidence in a population-based case-control study (United States)

Objective: To evaluate the potential interaction between N-acetyltransferase 2 (NAT2) and smoking in breast cancer incidence. Methods: The data are derived from a population-based case–control study of women aged 20–69 years who were residents of Massachusetts or Wisconsin during 1997–1998. Incident cases of invasive breast cancer were identified through state tumor registries and age-similar controls were selected at random from population lists. Telephone interviews were conducted to obtain information on known and suspected risk factors including smoking history. Women provided oral mucosal DNA through the mail for genetic studies. Results: A total of 791 cases and 797 controls were included in the analysis. Overall, smoking was modestly associated with breast cancer risk (multivariate odds ratio (OR) for ever smoking: 1.37; 95% confidence interval (CI): 1.12–1.69), and there was a trend in risk for greater pack-years of smoking among postmenopausal women (p for trend = 0.02). Overall, NAT2 was not related to invasive breast cancer (multivariate OR: 1.11; 95% CI: 0.90–1.36). Associations of smoking with breast cancer tended to be somewhat stronger among the women with the slow acetylator genotype for NAT2: when compared to those who never smoked and were rapid acetylators, the OR for ever smoking was 1.50 (95% CI: 1.11–2.02) in slow acetylators, and OR: 1.24 (95% CI: 0.91–1.70) in rapid acetylators. However, tests for multiplicative interaction were not significant in case–control comparisons, or in case-only analyses. Conclusion: Results of the study are compatible with the majority of previous studies that indicate little or no association of NAT2, smoking, or their interaction with the occurrence of breast cancer.     

Meat Consumption,Animal Products,and the Risk of Bladder Cancer: A Case-Control Study in Uruguayan Men

In the time period 1996-2004, all incident cases of bladder cancer were included in a case-control study inorder to study the role of meat consumption and product animals in the etiology of urothelial cancer. The studyincluded 225 cases and 1,510 hospitalized controls with non-neoplastic conditions, not related to smoking andalcohol drinking. Relative risks, approximated by the odds ratios, were calculated in order to clarify the effectof meat consumption in the etiology of urothelial cancer. Total meat consumption (OR 1.47, 95% CI 1.02-2.11),total processed meat (OR 1.57, 95% CI 1.08-2.27), frankfurters (hot dogs) (OR 2.03, 95% CI 1.28-3.21), ham(OR 1.79, 95% CI 1.21-2.67) and salted meat (OR 2.73, 95% CI 1.78-4.18) were positively associated with riskof bladder cancer. Animal products, like cheese, whole milk, and total eggs were also associated with bladdercancer risk (OR for eggs 4.05, 95% CI 2.68-6.12). In conclusion, total meat, processed meat, and eggs could playan important role in the etiology of bladder cancer in Uruguay.     

A Family-based Genetic Association Study of Variants in Estrogen-metabolism Genes COMT and CYP1B1 and Breast Cancer Risk

In this paper, we report findings from a family-based association study examining the association between polymorphisms in two key estrogen-metabolism genes CYP1B1 (codon 432 G --> C and codon 453 A --> G variants) and COMT (codon 158 G --> A variant) and female breast cancer. We conducted the study among 280 nuclear families containing one or more daughters with breast cancer with a total of 1124 family members (702 with available constitutional DNA and questionnaire data and 421 without). These nuclear families were selected from breast cancer families participating in the Metropolitan New York Registry (MNYR) - one of the six centers of NCI's Breast Cooperative Family Registry. We used likelihood-based statistical methods to examine the allelic associations. We found none of the variant alleles of the CYP1B1 and COMT genes to be associated with breast cancer in these families. This was consistent with results from matched case-control analyses using all available sib-ships in these families. However, we found that parental carrier status of the CYP1B1 codon 453 variant G allele and the COMT codon 158 variant A allele was associated with breast cancer risk in daughters (independent of the daughters' own genotype). In conclusion, findings from this family-based study indicate that a woman's own CYP1B1 or COMT genotypes are not associated with her breast cancer risk. Although the study found that parental carrier status of certain CYP1B1 or COMT genotypes might be associated with daughter's breast cancer risk, the biological basis as well as independent confirmation of this finding need to be investigated in future larger family-based studies before making meaningful inferences.     

Glutathione S-transferase M1 and P1 polymorphisms and risk of breast cancer and fibrocystic breast conditions in Chinese women

Enzymes encoded by the glutathione S-tranferase mu 1 (GSTM1) and pi 1 (GSTP1) genes, which are expressed in breast tissue, catalyze the detoxification of endogenous and exogenous electrophiles. Reduced enzyme activity, due to carriage of the GSTM1 deletion or the GSTP1 Ile105Val Val allele, may therefore affect susceptibility to breast cancer and related conditions. In a case-control study of Chinese women, we examined whether these polymorphisms were associated with risk of breast cancer and fibrocystic breast conditions. Women diagnosed with breast cancer (n = 615) or fibrocystic breast conditions (n = 467) were compared to women without clinical breast disease (n = 878). We also examined whether these associations differed by menopausal status or by presence of proliferation in the extra-tumoral epithelium among women with breast cancer and in lesions among women with fibrocystic conditions. No overall association of either GST polymorphism with risk of breast cancer or fibrocystic breast conditions was observed. There was some evidence of slightly elevated cancer risk associated with carriage of the GSTM1 null genotype and at least one GSTP1 105–Val allele (OR = 1.33, 95% CI, 0.99–1.80), compared to carriage of the GSTM1 non-null and GSTP1 Ile/Ile genotypes. This relationship was stronger in women who had breast cancer with extra-tumoral tissue proliferation (OR = 1.77, 95% CI, 1.03–3.04). Our results suggest that GSTM1 and GSTP1 genotypes do not individually influence susceptibility to breast cancer or fibrocystic breast conditions. The observed increased risk of breast cancer associated with joint carriage of the GSTM1 null genotype and GSTP1 105–Val allele needs confirmation in other studies.