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Purpose: The role of exogenous and endogenous sex hormones in the etiology of depression remains elusive, in part because sex hormone variation is often correlated with behaviors, life stage changes, and other factors that may influence depression. Estrogen receptor alpha (ESR1) and beta (ESR2) are known to regulate gene expression and estrogen response in areas of the brain associated with major depression and are unlikely to be correlated with exogenous factors that may influence depression., Methods: We examined whether functional polymorphisms in these genes are associated with lifetime major depression and chronic major depression among a sample of women from the Nurses' Health Study II (N = 2527). DSM-IV depressive disorder symptoms were assessed by structured interview in 2007. Genotyping was performed on DNA extracted from blood using Taq-man., Results: Women with the AA alleles of ESR2 RS4986938 had the higher prevalence of lifetime major depression than women with other allele frequencies (36.7 % for those with AA versus 28.5 % with GA and 29.1 % with GG, p = 0.02) and chronic major depression (14.7 % for those with AA versus 9.3 % with GA and 9.1 % with GG, p = 0.01). History of post-menopausal hormone (PMH) use modified the association of ESR1 polymorphism RS2234693 with any lifetime depression; specifically, those with the TT allele had the highest risk of lifetime depression among PMH users, and the lowest risk of depression among non-PMH users (p value for interaction = 0.02). Further, carriers of the AA alleles in ESR1 polymorphism RS9340799 had increased prevalence of lifetime major depression only among lifetime PMH users (p = 0.007)., Conclusions: Our findings support the hypothesis that estrogen receptor polymorphisms influence risk for major depression; the role of estrogen receptors and other sex steroid-related genetic factors may provide unique insights into etiology.

Bladder cancer results from the combined effects of environmental and genetic factors, smoking being the strongest risk factor. Evaluating absolute risks resulting from the joint effects of smoking and genetic factors is critical to assess the public health relevance of genetic information. Analyses included up to 3,942 cases and 5,680 controls of European background in seven studies. We tested for multiplicative and additive interactions between smoking and 12 susceptibility loci, individually and combined as a polygenic risk score (PRS). Thirty-year absolute risks and risk differences by levels of the PRS were estimated for U.S. males aged 50 years. Six of 12 variants showed significant additive gene-environment interactions, most notably NAT2 (P = 7 × 10(-4)) and UGT1A6 (P = 8 × 10(-4)). The 30-year absolute risk of bladder cancer in U.S. males was 6.2% for all current smokers. This risk ranged from 2.9% for current smokers in the lowest quartile of the PRS to 9.9% for current smokers in the upper quartile. Risk difference estimates indicated that 8,200 cases would be prevented if elimination of smoking occurred in 100,000 men in the upper PRS quartile compared with 2,000 cases prevented by a similar effort in the lowest PRS quartile (P(additive) = 1 × 10(-4)). Thus, the potential impact of eliminating smoking on the number of bladder cancer cases prevented is larger for individuals at higher than lower genetic risk. Our findings could have implications for targeted prevention strategies. However, other smoking-related diseases, as well as practical and ethical considerations, need to be considered before any recommendations could be made., (©2012 AACR.)

Cigarette smoking is inversely associated with endometrial cancer risk. Smoking is proposed to decrease risk, in large part, through its anti-estrogenic effects in the uterus. In addition, cigarette smoke is a major source of alkylation damage. The O6-methylguanine DNA methyltransferase (MGMT) gene is responsible for repairing alkylation DNA damage and also has a role in inhibiting estrogen receptor-mediated cell proliferation. Because of MGMT's dual functions, it is a strong candidate gene for endometrial cancer. We assessed the two functional polymorphisms, the Leu84Phe and Ile143Val, in relation to endometrial cancer risk in a nested case-control study within the Nurses' Health Study (cases = 456, controls = 1134). Compared with the 84Leu/Leu genotype, the Phe carriers had a significantly decreased risk of endometrial cancer [odds ratio (OR), 0.72; 95% confidence interval (CI), 0.53-0.96]. We did not observe an association between the Ile143Val polymorphism and endometrial cancer risk overall. We observed a significant multiplicative interaction between the Ile143Val polymorphism and pack-years of smoking on endometrial cancer risk (P, interaction, 0.04); the inverse association of pack-years with endometrial cancer risk was limited to the 143Val carriers (P, trend, 0.01). Compared with women who had the Ile/Ile genotype and never smoked, the 143Val carriers who had >30 pack-years of smoking had a significantly decreased risk of endometrial cancer (OR, 0.41; 95%CI, 0.19-0.86). These data suggest that these two polymorphisms may influence endometrial cancer risk.

Obesity and the associated pathologies including dyslipidemia, insulin resistance, type 2 diabetes, and cardiovascular disease constitute a major threat to global human health. Yet, the genetic factors that differentially predispose individuals to this cluster of pathologies are unclear. The fatty acid-binding protein aP2 is a cytoplasmic lipid chaperon expressed in adipocytes and macrophages. Mice with aP2 deficiency are partially resistant to obesity-induced insulin resistance and type 2 diabetes, have lower circulating triglycerides, and exhibit marked protection against atherosclerosis. Here, we demonstrate a functionally significant genetic variation at the aP2 locus in humans that results in decreased adipose tissue aP2 expression due to alteration of the CAAT box/enhancer-binding protein binding and reduced transcriptional activity of the aP2 promoter. In population genetic studies with 7,899 participants, individuals that carry this T-87C polymorphism had lower serum triglyceride levels and significantly reduced risk for coronary heart disease and type 2 diabetes compared with subjects homozygous for the WT allele. Taken together, our results indicate that reduction in aP2 activity in humans generate a metabolically favorable phenotype that is similar to aP2 deficiency in experimental models.

The androgen receptor (AR) gene is a transcription factor responsible for mediating the physiological effects of androgens. Evidence suggests that androgens and the androgen receptor are involved in uterine cell proliferation. A polymorphic CAG repeat in exon 1 of the AR gene encodes a polyglutamine tract that is inversely correlated with the transcriptional activity of this gene. We assessed the association between the functional CAG repeat polymorphism and AR haplotypes and the risk of endometrial cancer in two nested case-control studies within the Nurses' Health Study (n = 222 cases, 666 controls) and the Women's Health Study (n = 137 cases, 411 controls) using conditional and unconditional logistic regression. Associations between AR CAG repeat polymorphism and endometrial cancer risk were similar in the 2 case-control studies. In the pooled analysis, women with an average repeat allele > or =22 repeats compared to <22 repeats were at a statistically significant decreased risk of endometrial cancer (odds ratio (OR) = 0.76; 95% confidence interval (CI), 0.59-0.98). Women with one or two long alleles (> or =27 repeats) compared to both alleles <22 repeats were also at a statistically significant decreased risk (OR = 0.60; 95% CI, 0.36-0.99). We observed a modest yet statistically significant association for each one unit increase in the average repeat length and endometrial cancer risk (OR = 0.94; 95% CI, 0.88-1.00). Associations for the AR CAG average repeat length and endometrial cancer risk differed by menopausal status (p = 0.02). No significant associations between the AR haplotypes and endometrial cancer risk were observed. Our findings suggest that an increasing number of functional CAG repeats may be associated with endometrial carcinogenesis because of AR's reduced ability to recruit coregulators and other transcriptional components. (supplementary material for this article can be found on the International Journal of Cancer website at http://www.interscience.wiley.com/jpages/0020-7136/suppmat/index.html)., ((c) 2005 Wiley-Liss, Inc.)

Endogenous estrogen exposure is an important determinant of endometrial cancer risk. Aromatase, encoded by CYP19, catalyzes the aromatization of androstenedione and testosterone to estrone and estradiol, respectively. Several common genetic polymorphisms in CYP19 have been identified, including a TCT insertion/deletion and a (TTTA)(n) repeat polymorphism in intron IV as well as a 3'UTR C/T polymorphism. We evaluated these 3 polymorphisms plus an additional 9 noncoding polymorphisms as individual genotypes and predicted haplotypes as risk factors for endometrial cancer using a nested case-control study design. Invasive endometrial cancer cases (n = 222) and matched controls (n = 666) were identified among participants in the Nurses' Health Study who had provided a blood sample in 1989-1990 (n = 32,826). We estimated haplotypes from unphased genotype data spanning > 123 kb of CYP19. Six haplotypes constructed from 10 SNPs were estimated with a frequency > or = 5%. The highest prevalence haplotype (33% among cases, 28% among controls) was significantly associated with endometrial cancer risk (p = 0.03). Loci with variant alleles that comprise the risk haplotype were independently associated with endometrial cancer, with relative risk estimates ranging from 1.68 (95% CI 1.13-2.48) to 2.07 (95% CI 1.33-3.23), comparing variant allele carriers to wild-type homozygotes. We observed significant interactions between menopausal status and 2 of the high-risk loci (p = 0.03 and p < 0.01), with > 2-fold increased risk for variant allele carriers who were postmenopausal but no association between genotype and endometrial cancer among premenopausal women. We evaluated associations between CYP19 haplotypes and plasma steroid hormone levels. The haplotype associated with endometrial cancer risk is also significantly associated with the ratios of estrone to androstenedione and estradiol to testosterone, the products and substrates of the enzyme aromatase, encoded by CYP19. Our data suggest that there is a high-frequency CYP19 haplotype related to higher estrogen to androgen ratios and increased risk of endometrial cancer and that this association may primarily pertain to postmenopausal women., (Copyright 2005 Wiley-Liss, Inc.)

Endogenous oestrogens play a crucial role in endometrial cancer pathogenesis, with most endometrial cancer risk factors causing an increase in oestrogens. Adipose tissue, where androgens are converted to oestrogens by the enzyme aromatase, is an important source of endogenous oestrogen production in the postmenopausal woman. The peroxisome proliferator-activated receptor-gamma (PPARgamma), a key transcriptional regulator of adipogenesis, may also play a role in the regulation of aromatase expression in adipose tissue. We hypothesized that the functional PPARgamma ProAla polymorphism may alter aromatase expression, ultimately affecting endometrial cancer susceptibility. We genotyped the PPARgamma ProAla polymorphism in a study of invasive endometrial cancer cases (n = 222) and matched controls (n = 666) nested within the Nurses' Health Study Cohort. We found little or no evidence of an association between the Ala allele of the PPARgamma codon 12 polymorphism and endometrial cancer risk (adjusted odds ratio = 1.18, 95% confidence interval = 0.80-1.76). Furthermore, we found no association with the PPARgamma ProAla polymorphism and the ratio of oestrone to androstenedione or oestradiol to testosterone plasma hormone levels, measures of aromatase activity. Consistent with previous findings for breast cancer, these results suggest that the PPARgamma ProAla polymorphism does not play a major role in mediating circulating oestrogen levels or endometrial cancer susceptibility.

Objective: We hypothesized that variations in the ESR2 gene may influence estrogen exposure in the uterus and thus influence endometrial cancer risk. We validated and screened for variants in the ESR2 gene and examined whether they are associated with endometrial cancer risk., Methods: We resequenced the promoter and coding regions of the ESR2 gene in 24 endometrial cancer cases, and genotyped the validated/discovered SNPs and intronic dinucleotide CA repeat in a nested case-control study of endometrial cancer (cases = 222, controls = 666) in the Nurses' Health Study (NHS). We also explored statistical interaction between ESR2 genotypes and body mass index (BMI) or hormone replacement therapy (HRT) use among postmenopausal women and cancer risk., Results: Two SNPs were validated [rs1256049 in exon 5 (allelic frequencies = 98% G, 2% A) and rs1271572 in the promoter region (allelic frequencies = 60% G, 40% T)]. After adjusting for potential confounders, we observed no association between ESR2 gene polymorphisms and endometrial cancer risk [rs1256049 (OR = 1.2; 95%CI: 0.7-2.3), rs1271572 (OR = 0.8; 95%CI: 0.5-1.1) and CA repeat (22 repeat allele versus > or = 22 repeat allele, OR = 1.1; 95%CI: 0.7-1.7)]. We also did not observe any significant effect modification of the ESR2 polymorphisms by BMI or HRT use among postmenopausal women., Conclusion: Our results indicate that ESR2 polymorphisms may not be associated with endometrial cancer risk., (Copyright 2004 Kluwer Academic Publishers)

Estrogen production and metabolism play critical roles in the development and pathogenesis of endometrial carcinoma. Cytochrome P450 1B1 (CYP1B1) and catechol-O-methyltransferase (COMT) are two key enzymes in the estrogen metabolism pathway that result in the hydroxylation and conjugation of estradiol, respectively. We evaluated the association between the CYP1B1 Leu432Val and CYP1B1 Asn453Ser polymorphisms and the COMT Val158Met polymorphism and invasive endometrial cancer risk in a case-control study nested within the Nurses' Health Study (n = 222 cases, 666 controls). We also evaluated whether body mass index (BMI), postmenopausal hormone (PMH) use and cigarette smoking modified the associations of the CYP1B1 and COMT genotypes and endometrial cancer risk. Conditional logistic regression was used to calculate the adjusted odds ratios (OR) and 95% confidence intervals (CI) to quantify the risk of endometrial cancer among subjects who had at least one variant allele compared with subjects who were homozygous for the wild-type allele. Carriers of the CYP1B1 Ser allele had a statistically significant decreased risk of endometrial cancer (OR = 0.62; 95% CI, 0.42-0.91); there was no significant association between the CYP1B1 Val allele and endometrial cancer risk (OR = 1.10; 95% CI, 0.75-1.59). Compared with the COMT Val/Val wildtype genotype, the adjusted OR of endometrial cancer for women with the COMT Val/Met or COMT Met/Met genotype was 0.96 (95% CI, 0.65-1.43). We did not observe any effect modification by BMI, PMH use and cigarette smoking for the CYP1B1 and COMT genotypes. Our data suggest, that the CYP1B1 Ser allele may decrease endometrial cancer risk by altering the production of catechol estrogens. However, further studies are warranted to elucidate the role of CYP1B1 in endometrial cancer.

Genetic polymorphisms in double-strand break repair genes may influence DNA repair capacity and, in turn, confer predisposition to breast cancer. We prospectively assessed the associations of candidate polymorphisms G31479A (R188H) in XRCC2, A4541G (5'-UTR), A17893G (IVS5-14) and C18067T (T241 M) in XRCC3, and C299T (5'-UTR) and T1977C (D501D) in Ligase IV with breast cancer risk in a nested case-control study within the Nurses' Health Study (incident cases, n=1004; controls, n=1385). We observed no overall associations of these six genotypes with breast cancer risk. Four common haplotypes in XRCC3 accounted for 99% of the chromosomes of the present study population. We observed that Ligase IV 1977C carriers were at increased breast cancer risk if they had a first degree family history of breast cancer (test for interaction, P=0.01). We observed that the XRCC2 R188H polymorphism modified the association of plasma alpha-carotene level and breast cancer risk (test for ordinal interaction, P=0.03); the significantly decreased risk seen overall for women in the highest quartile of plasma alpha-carotene was only present among 188H non-carriers (the top quartile versus the bottom quartile; multivariate odds ratio, 0.55; 95% confidence interval, 0.40-0.75). No significant interactions were seen between any of these polymorphisms and duration or dose of cigarette smoking. The gene-environment interaction data suggest that the subtle effects of some of these variants on breast cancer risk may be magnified in the presence of certain exposures.

Estrogen exposure influences breast and endometrial cancer risk. The HSD17B1 gene produces an enzyme that catalyzes the conversion of estrone to estradiol. We hypothesized that genetic variations in HSD17B1 gene may alter endogenous estrogen levels and, thus, influence endometrial and breast cancer risk. We validated and genotyped polymorphisms in the HSD17B1 gene and assessed whether these single nucleotide polymorphisms (SNPs), or the imputed haplotypes, were associated with endometrial and breast cancer risk. We also assessed whether a priori risk factors modified the associations between HSD17B1 genotype and cancer risk, and whether HSD17B1 genotypes were associated with plasma estrogen levels among postmenopausal women not using hormone replacement therapy. Ten SNPs of HSD17B1 gene were validated in 30 women from the Nurses' Health Study. Using the expectation maximization algorithm, three common (>5% frequency) haplotypes accounted for 97% of the chromosomes at this locus, and seven SNPs were in complete linkage disequilibrium. We identified and genotyped two haplotype-tagging SNPs (+1004C/T and +1322C/A), and genotyped an additional SNP [+1954A/G (Ser312Gly)] in nested case-control studies of endometrial cancer (cases = 222, controls = 666) and breast cancer (cases = 1007, controls = 1441) in the prospective Nurses' Health Study. Although no overall association by SNP or haplotype analysis was observed with endometrial or breast cancer risk, the +1954A/A genotype was associated with higher estradiol levels in lean women (P = 0.01) and interaction between the +1954 genotype with body mass index in postmenopausal breast cancer (P = 0.05) was suggested. These findings suggest that the HSD17B1 may be associated with circulating estradiol levels and interact with body mass index in postmenopausal breast cancer.

The peroxisome proliferator-activated receptor gamma (PPAR gamma) is a critical regulator of adipogenesis. PPAR gamma+/- mice are resistant to high-fat diet-induced obesity and thus PPAR gamma may mediate physiological responses to dietary fat in other mammals. The aim of this study was to determine whether the human PPAR gamma proline to alanine substitution polymorphism (Pro12Ala) modifies the association between dietary fat and adiposity and plasma lipids. Subjects (n=2141) were controls selected for three case-control studies nested within the Nurses' Health Study, a large ongoing prospective cohort study. Associations between intake of total fat, fat subtypes and BMI were different in PPAR gamma 12Ala variant allele-carriers compared with non-carriers. Among homozygous wild-type Pro/Pro individuals, those in the highest quintile of total fat intake, had significantly higher mean body mass index (BMI) compared with those in the lowest quintile (27.3 versus 25.4 kg/m2, respectively; P-trend<0.0001) whereas among 12Ala variant allele-carriers there was no significant trend observed between dietary fat intake and BMI (P-trend=0.99; P-interaction=0.003). In contrast, intake of monounsaturated fat was not associated with BMI among homozygous wild-type women but was inversely associated with BMI among 12Ala variant allele-carriers (mean in lowest quintile=27.6 versus mean in highest quintile=25.5 kg/m2; P-trend=0.006; P-interaction=0.003). The relationship between dietary fat intake and plasma lipid concentrations also differed according to PPAR gamma genotype. These data suggest that PPAR gamma genotype is an important factor in physiological responses to dietary fat in humans.

Objective: Polymorphic variants of the human progesterone receptor gene have been described, but their potential influence on in vitro fertilization outcome have not been studied., Study Design: DNA was available from 317 women (cases) who had >or=2 embryo transfers without a clinical pregnancy and from 288 women (control subjects) who became pregnant after 1 in vitro fertilization attempt. With protocols that were specific for H770H (C/T genotype) and +331G/A polymorphism, amplification of polymorphism fragments, digestion with restriction enzymes, and gel visualization were performed., Results: Allele frequencies for the 2 variants were 15.5% for H770H T and 4.1% for +331A in cases and 17.9% and 3.6% in control subjects, respectively. Both polymorphisms were rare among non-white subjects. Possession of a H770H T allele was associated with a decreased risk for implantation failure, which was nonsignificant overall but significant in women aged <35 years (adjusted relative risk, 0.52 [95% CI, 0.28, 0.97]). Possession of a +331A allele was associated with an increased risk of implantation failure, which was nonsignificant overall but significant in women who weighed <135 pounds (adjusted relative risk, 3.85 [95% CI, 1.20, 12.30]). The +331G/A polymorphism tended to increase the risk for implantation failure in women with an H770H C/C genotype, but not in women with a C/T or TT genotype (P=.09). Among white women who were H770H C/C, there was a significant trend (P=.03) in the proportion of +331G/A carriers as the number of implantation failures increased, from 8.6% of women with 0 failed attempts to 40% among women with >or=5 failed attempts., Conclusion: Although human progesterone receptor polymorphisms do not clearly affect the risk for implantation failure in most women who undergo in vitro fertilization, the likelihood that a woman carries the +331G/A human progesterone receptor polymorphism increases with the number of failed attempts at implantation.

Background: GSTP1 is a gene that helps detoxify foreign substances in the body. Functional polymorphisms of GSTP1 have been studied as risk factors for lung cancer. Past studies have compared the effect of the "at risk" polymorphism in two strata of smoking pack-years (usually defined by the median among controls). We examined the interaction between GSTP1 polymorphisms and cumulative exposure to smoking and their association with lung cancer risk., Methods: Data are from a large hospital-based case-control study of persons treated for primary lung cancer at the Massachusetts General Hospital since 1992. Controls were drawn from friends and nonrelated family members. We genotyped 1,042 cases and 1,161 controls for GSTP1 using polymerase chain reaction-restriction fragment length polymorphism techniques., Findings: The GSTP1 GG genotype approximately doubled the lung cancer risk associated with pack-years. This interaction was stronger among current smokers. At 26 pack-years (median among controls with a smoking history), the adjusted odds ratio for the association between pack-years and lung cancer risk was 13 (95% confidence interval = 6.5-25) among current smokers with the GSTP1 GG genotype compared with 6.1 (95% confidence interval = 4.9-7.5) among those with the GSTP1 AA genotype., Conclusions: GSTP1 GG increases the lung cancer risk associated with pack-years of smoking.

Environmental Tobacco Smoke (ETS) exposure has been associated with lung cancer risk. ETS is composed of emissions from cigarette smoke and contains a higher concentration of tobacco smoke carcinogens than mainstream smoke. Polymorphisms in genes that metabolize tobacco smoke carcinogens have been studied as effect modifiers of the association between active smoking and lung cancer risk. GSTP1 is a polymorphic gene that encodes for GST pi, a detoxification enzyme and has a high expression in the lung. We investigated the association between ETS and lung cancer risk and the modification of this association by the GSTP1 polymorphism. Using a case-control design, individuals were genotyped for GSTP1 using PCR-RFLP techniques. All analyses were carried out using multiple logistic regression. The association between ETS exposure and lung cancer risk was evaluated in different strata based on smoking habits to evaluate the consistency of results. The effect of the GSTP1 polymorphisms on lung cancer risk was evaluated by considering the joint effect of having both an ETS exposure and the GSTP1 GG genotype compared to the absence of ETS exposure and the GSTP1 AA genotype as a reference group as well as doing stratified analysis by genotype. ETS exposure was associated consistently with higher lung cancer risk in all the strata considered. The adjusted odds ratios (AOR) evaluating the association between ETS and lung cancer risk for the different strata were: nonsmokers (Cases/Controls 66/413; AOR = 1.38; 95% CI = 0.78-2.43), ex-smokers (Cases/Controls 560/527; AOR = 1.66; 95% CI = 1.22-2.25), current smokers (Cases/Controls 415/219; AOR = 1.56; 95% CI = 1.00-2.41). The AORs for ex-smokers and light smoking subgroups were: ex-smokers who quit for 19 years or more (Cases/Controls 144/244; AOR = 2.64; 95% CI = 1.55-4.50), ex-smokers who quit for 10-19 years (Cases/Controls 141/128; AOR = 1.16; 95% CI = 0.66-2.04), ex-smokers who quit for 10 years or less (Cases/Controls 247/122; AOR = 1.45; 95% CI = 0.83-2.55) and participants who had <15 packyears and nonsmokers combined (Cases/Controls 143/640; AOR = 1.52; 95% CI = 1.02-2.28). Among those with the GSTP1 GG genotype the ETS-lung cancer risk association was greater than those with the GSTP1 AA genotype: nonsmokers (GSTP1 GG AOR = 7.84; 95% CI = 0.80-76.68; GSTP1 AA AOR = 1.15; 95% CI = 0.46-2.90), ex-smokers (GSTP1 GG AOR = 2.32; 95% CI = 0.90-5.96; GSTP1 AA AOR = 2.15; 95% CI = 1.34-3.44), current smokers (GSTP1 GG AOR = 1.75; 95% CI = 0.42-7.32; GSTP1 AA AOR = 1.32; 95% CI = 0.67-2.58) and participants who had <15 packyears and nonsmokers (GSTP1 GG AOR = 1.93; 95% CI = 0.54-6.97; GSTP1 AA AOR = 1.58; 95% CI = 0.83-3.01). We found that ETS exposure is associated with higher lung cancer risk. Furthermore, the presence of the GSTP1 GG genotype appears to enhance the magnitude of the association between ETS exposure and lung cancer. Larger studies will be needed to confirm these preliminary findings., (Copyright 2003 Wiley-Liss, Inc.)

Excessive estrogen stimulation unopposed by progesterone strongly predisposes to endometrial cancer. Because the antiproliferative effect of progesterone requires the progesterone receptor (PR), which exists in two isoforms, PR-A and -B, we reasoned that variants in the PR gene may predispose to endometrial cancer. We found six variable sites, including four polymorphisms in the hPR gene and five common haplotypes. One promoter region polymorphism, +331G/A, creates a unique transcription start site. Biochemical assays showed that the +331G/A polymorphism increases transcription of the PR gene, favoring production of hPR-B in an endometrial cancer cell line. Using a case-control study nested within the Nurses' Health Study cohort, we observed a statistically significant association between the +331G/A polymorphism and the risk of endometrial cancer, which was even greater in overweight women carriers. After including a second population of controls, these associations remained intact. Our findings suggest that the +331G/A hPR gene polymorphism may contribute to endometrial cancer risk by increasing expression of the hPR-B isoform.

Background: A polymorphism (G to A transition) in intron 13 of the mitochondrial enzyme monoamine oxidase B (MAOB) gene may modify, alone or by interacting with the catechol-O-methyltransferase (COMT(LL)) genotype (low enzymatic activity), the risk of idiopathic PD. Also, the association between never smoking and PD risk may be present only in people with the MAOB G allele., Methods: The authors studied two ongoing prospective cohorts-the Nurses' Health Study (121,700 women aged 30 to 55 in 1976) and the Health Professionals' Follow-up Study (51,529 men aged 40 to 75 in 1986). They identified new PD cases through 1996, selected random control subjects matched on age and study cohort, and obtained DNA samples from blood or buccal smears from 85% of the eligible cases and 84% of the control subjects. They included genotypes from 214 cases and 449 control subjects, all Caucasian., Results: The odds ratio of PD was 1.2 (95% CI 0.9, 1.7) for MAOB genotypes G/GG/GA compared with genotypes A/AA, and 1.1 (0.7, 1.8) for COMT genotypes LL compared with HH. The odds ratio (95% CI) was 1.7 (0.7, 3.9) for those with MAOB G/GG and COMT(LL) genotypes compared with those with MAOB A/AA and COMT(HH). There was a strong association between never smoking and PD risk in all groups defined by MAOB and COMT genotypes., Conclusion: The findings do not support a major role of the MAOB intron 13 polymorphism in the development of PD, either by itself or by interacting with smoking.

Cytochrome P450 1B1 catalyzes the conversion of 17-beta-estradiol (E2) to thecatechol estrogen metabolites 2-OH-E2 and 4-OH-E2 that have been postulated to be involved in mammary carcinogenesis. We sought to determine whether two common functional polymorphisms in Cytochrome P450 1B1, V432L (m1), and A453S (m2) are related to breast cancer risk. Using a nested case control design within the Nurses' Health Study cohort, we genotyped 453 cases and 456 controls and found no significant association between m1[val/leu and leu/leu versus val/val, OR = 1 (CI, 0.72-1.45)] or m2 [asn/ser and ser/ser versus asn/asn, OR = 0.8 (CI, 0.62-1.15)] and breast cancer risk. However, we did observe women with the Val/Val (m1) genotype to have a higher percentage of estrogen receptor-positive tumors (P = 0.03). We did not observe any correlation with the m2 genotypes and estrogen receptor status. The association of the m1 and m2 genotypes on plasma hormone levels in postmenopausal control women not using hormone replacement therapy was also evaluated. Carriers of the m1 leu and m2 ser alleles had modestly higher estradiol levels but similar estrone and estrone sulfate levels. The results presented do not support a strong association between m1 and m2 and the risk of breast cancer.

UDP-glucuronosyltransferases (UGTs) catalyze the detoxification and the elimination of a large number of endogenous and exogenous compounds in the liver and extrahepatic tissues. One of the UGT1A family members, UGT1A1, is involved in estradiol metabolism and, therefore, represents a candidate gene in breast carcinogenesis. A common insertion/deletion polymorphism in the TATA-box of the promoter region of UGT1A1 results in decreased initiation of transcription. In a previous study, we found a positive association between the UGT1A1 low-transcriptional alleles and premenopausal breast cancer risk in an African-American population. In the present study, we sought to determine whether the low-transcription UGT1A1 promoter allele, UGT1A1*28 [A(TA)(7)TAA], was associated with increased breast cancer risk among primarily Caucasian women in a nested case-control study within the Nurses' Health Study cohort. No significant association between the UGT1A1*28 [A(TA)(7)TAA] allele and breast cancer was observed. Compared with women homozygous for the UGT1A1*1 [A(TA)(6)TAA] allele, the relative risk was 0.80 (confidence interval, 0.49-1.29) for women homozygous for the UGT1A1*28 allele. The effect of the UGT1A1 genotype on plasma hormone levels in postmenopausal women not using hormone replacement was also evaluated, and overall, no significant differences in hormone levels by genotypes were observed. When restricted to women who had at least one UGT1A1*28 allele and a body mass index at blood draw of >27 kg/m(2), particularly in combination with the cytochrome p450c17alpha genotype, estrone and estradiol levels tended to vary by UGT1A1 genotypes. The results presented do not support a strong association between the UGT1A1 promoter polymorphism and the risk of breast cancer.

Among women, the A2 allele of CYP17 has been associated with elevated levels of endogenous steroid hormones; however, it does not seem to be a strong independent risk factor for breast cancer. We assessed the association between the A2 allele of CYP17 and invasive endometrial cancer risk in a case-control study nested within the Nurses' Health Study cohort (cases: n = 184; controls: n = 554). We also evaluated whether endometrial cancer risk associated with CYP17 genotype was modified by established endometrial cancer risk factors. In addition, we further examined the relationship between CYP17 genotype and endogenous plasma steroid hormone levels among postmenopausal controls not using hormone replacement therapy (HRT). Women with the A2 allele of CYP17 were at decreased risk of endometrial cancer (A1/A1 genotype (reference); A1/A2 genotype: odds ratio, 0.89; 95% confidence interval, 0.62-1.27; A2/A2 genotype: odds ratio, 0.43; 95% confidence interval, 0.23-0.80; P trend, 0.02). We also observed the inverse association between the A2 allele and endometrial cancer risk to be stronger among women with a first-degree family history of endometrial and/or colorectal cancer (P for interaction, 0.05). Among 165 controls, we did not observe women with the A2 allele to have significantly elevated levels of any steroid hormone fraction. When these women were combined and analyzed with those women on whom we had previously examined the relationship between CYP17 genotype and circulating hormone levels (total n = 469), only modest associations were observed for the A2/A2 genotype and steroid hormone fractions estrone (versus A1/A1 genotype: +10.9%; P = 0.05) and estradiol (+8.5%; P = 0.17). These data suggest that the A2 allele of CYP17 decreases endometrial cancer risk, but has only weak effects on endogenous estrogen levels among postmenopausal women.

The CYP19 gene codes for aromatase, a key steroidogenic enzyme involved in the conversion of androgens to estrogens. A tetranucleotide (TTTA) repeat polymorphism is present in intron 4 of CYP19; 2 out of 4 breast cancer case-control studies have reported a greater frequency of 2 specific alleles among affected women. We evaluated associations between CYP19 repeat alleles and breast cancer risk in a case-control study nested within the Nurses' Health Study cohort (incident cases: n=462; controls: n=618). We observed seven different CYP19 alleles (TTTA(7-13)). Compared to controls, cases had a statistically significant greater frequency of the 10 (TTTA)(10) repeat allele (10 allele: 2.3% vs. 0.7%, p = 0.005) and a nonsignificant increase in the frequency of the 12 (TTTA)(12) allele (12 allele: 3.1% vs. 2.1%, p = 0.11). A higher frequency of the 10 allele was observed in more advanced cancer cases defined as four or more involved nodes or distant metastasis [4+ nodes: 5/36 (13.9%) vs. 0-3 nodes: 13/330 (3.9%), p = 0.02]. Among controls, we found women with the 7 repeat allele to have decreased levels of estrone sulfate (-16.4%, p = 0.02), estrone (-6.1%, p = 0.22) and estradiol (-9.9%, p = 0.10), and a lower estrone/androstenedione ratio (E1/A) (-10.5%, p = 0.08) compared to non-carriers. A higher E1/A ratio and elevated estrogen levels were observed among carriers of the 8 repeat allele; E1/A ratio (+21.0%, p = 0.003), estrone (+7.5%, p = 0.16) and estradiol (+10.8%, p = 0.08). However, we observed no evidence of an association between these alleles and breast cancer risk. We were unable to make inferences regarding the effect of the 10 allele on hormone levels due to the small number of allele carriers in the subgroup with hormone levels. As this repeat polymorphism is not close to the splice sites in intron 4, linkage disequilibrium with other functional polymorphisms in CYP19 may explain the findings of an increased association between breast cancer and the 10 allele variant of CYP19. We did not detect any sequence variants in the regulatory region or in the adipose-specific exon I.4. The lack of an established effect on CYP19 function associated with the 10 allele means that these findings should be interpreted with caution., (Copyright 2000 Wiley-Liss, Inc.)