Vitamin D receptor polymorphisms and risk of epithelial ovarian cancer

The vitamin D receptor (VDR) is a critical mediator of the cellular effects of vitamin D. The associations between four common VDR polymorphisms (BSMI, APAI, TAQI, and FOKI) and risk of epithelial ovarian cancer (EOC) were assessed in a case-control study nested within two prospective cohorts. One hundred seventy incident cases of EOC and 323 individually matched controls were genotyped. Overall, no associations were observed in genotype analyses. Haplotypes combining three SNPs in high linkage disequilibrium (BSMI, APAI, and TAQI) were also not associated with risk. These observations do not support a role for BSMI, APAI, TAQI, and FOKI polymorphisms in epithelial ovarian cancer in a predominantly Caucasian population.     

Vitamin D receptor gene polymorphisms and breast cancer risk.

PURPOSE: The steroid hormone 1,25-dihydroxyvitamin D3 is thought to protect against breast cancer. The actions of 1,25-dihydroxyvitamin D3 are mediated via the vitamin D receptor (VDR), and a number of polymorphisms in the VDR gene have been identified. These result in distinct genotypes, some of which may alter susceptibility to breast cancer. We have investigated whether specific VDR gene polymorphisms are associated with breast cancer risk in a United Kingdom Caucasian population. EXPERIMENTAL DESIGN: In a retrospective case-control study, female breast cancer patients (n = 398) and control women (n = 427) were recruited, and three VDR polymorphisms were determined. RESULTS: The 3' VDR polymorphisms BsmI and variable-length poly(adenylate) sequence were both significantly associated with breast cancer risk; odds ratios (adjusted for age menopausal status and hormone replacement therapy usage) for bb genotype versus BB genotype = 1.92 (95% confidence interval, 1.20-3.10; P < 0.01) and for LL versus SS = 1.94 (95% confidence interval, 1.20-3.14; P < 0.01). A 5' VDR gene variant, FokI, was not associated with breast cancer risk when analyzed in isolation (P > 0.05). However, FokI did modulate the increased risk associated with the bb/LL genotype such that possession of one or more F alleles together with the bb/LL genotype augmented breast cancer risk. Furthermore, the highest proportion of bb and FFLL/FfLL genotypes occurred in women with metastatic breast cancer. CONCLUSIONS: VDR polymorphisms are associated with breast cancer risk and may be associated with disease progression. Additional investigations into how different genotypes may affect the functional mechanisms of the VDR will provide a better strategy for identifying women at risk of breast cancer and for developing improved treatments.     

The Relationship Between eNOS Polymorphisms With Age,Smoking, Body Mass Index,and Clinicopathologic Parameters in Patients With Breast Cancer in Comparison With a Control Group

IntroductionNitric oxide (NO) is a free radical involved in carcinogenesis and is synthesized by endothelial nitric oxide synthase (eNOS). Genetic changes in the eNOS enzyme affect its activity, and the nitric oxide produced by inhibiting apoptosis can lead to cancer cell proliferation and metastasis. In this study, in addition to investigating the relationship between genetic changes in eNOS gene and the risk of breast cancer, the relationship between genotypes of polymorphisms, age, smoking, body mass index, and clinopathologic parameters was also investigated.Material and MethodsThree functional (Intron 4a/b, T786C, and G894T) and 1 tagging (G10T) polymorphisms of the eNOS gene were examined in 203 patients with breast cancer and 203 control subjects, and their genotypes were identified by restriction fragment length polymorphism polymerase chain reaction.ResultsThe T allele in G10T polymorphism increased the risk of breast cancer by 1.503-fold, whereas allele a in Intron 4, T allele in G894T, and C allele in T786C decreased its risk by 0.678-, 0.440-, and 0.525-fold, respectively. GG, GT (G10T), bb and ab (Intron4), GG and TT (G894T), and TT and CC (T786C) genotypes were significantly correlated with body mass index. There was a significant relationship between age and bb genotype, cigarette smoking and genotype ab (Intron 4), and estrogen receptor and GG (G10T) genotype. Tumor invasion factor was also significantly associated with TT (G10T), bb (Intron 4), and TT (T786C) genotypes.ConclusionGenetic changes in eNOS appear to have a dual role in breast cancer rate owing to changes in NO production and can be introduced as one of the genetic markers involved in breast cancer by evaluating the genotype of different populations.     

Association of A vitamin D receptor polymorphism with sporadic breast cancer development

Breast cancer is the leading cause of cancer death among Australian women and its incidence is annually increasing. Genetic factors are involved in the complex etiology of breast cancer. The seco-steroid hormone, 1.25 dihydroxy vitamin D3 can influence breast cancer cell growth in vitro. A number of studies have reported correlations between vitamin D receptor (VDR) gene polymorphisms and several diseases including prostate cancer and osteoporosis. In breast cancer, low vitamin D levels in serum are correlated with disease progression and bone metastases, a situation also noted in prostate cancer and suggesting the involvement of the VDR. In our study, 2 restriction fragment length polymorphisms (RFLP) in the 3' region (detected by Apa1 and Taq1) and an initiation codon variant in the 5' end of the VDR gene (detected by Fok1) were tested for association with breast cancer risk in 135 females with sporadic breast cancer and 110 cancer-free female controls. Allele frequencies of the 3' Apa1 polymorphism showed a significant association (p = 0.016; OR = 1.56, 95% CI = 1.09-2.24) while the Taq1 RFLP showed a similar trend (p = 0.053; OR = 1.45, 95% CI = 1.00-2.00). Allele frequencies of the Fok1 polymorphism were not significantly different (p = 0.97; OR = 0.99, 95% CI = 0.69-1.43) in the study population. Our results suggest that specific alleles of the VDR gene located near the 3' region may identify an increased risk for breast cancer and justify further investigation of the role of VDR in breast cancer.     

Vitamin D receptor genotype and breast cancer in Latinas (United States)

Objective: Polymorphism in the vitamin D receptor (VDR) gene has been associated with variation in bone mineral density and with prostate cancer risk. The purpose of this study was to determine whether polymorphism in the VDR gene may also influence breast cancer risk.Methods: Polymorphisms in the 5 and 3 ends of the VDR gene were genotyped for 143 Latina women with breast cancer and 300 cohort controls.Results: Both the BsmI and poly-A polymorphisms in the 3 end of the VDR gene were associated with breast cancer risk, with a trend for increasing risk with increasing number of BsmI B alleles or short (S) poly-A alleles. Compared to subjects having two long poly-A alleles (genotype LL), odds ratios (and 95% confidence intervals) were 1.5 (1.0–2.3) and 3.2 (1.5–6.9) for subjects having genotypes SL and SS, respectively. Compared to BsmI genotype bb, odds ratios (and 95% confidence intervals) were 1.6 (1.1–2.5) and 2.2 (1.0–4.7) for genotypes Bb and BB respectively. The start codon polymorphism, FokI, was not associated with breast cancer risk.Conclusion: These results suggest that polymorphic variation in or near the 3 end of the VDR gene influences breast cancer risk in Latina women.     

Influence of Genotype and Haplotype of MDR1 (C3435T,G2677A/T,C1236T) on the Incidence of Breast Cancer - a Case-Control Study in Jordan

Background: Breast cancer is the leading cause of cancer death among women and the second in humans worldwide. Many published studies have suggested an association between MDR1 polymorphisms and breast cancer risk. Our aim was to study the association between genetic polymorphism of MDR1 at three sites (C3435T, G2677A/T, and C1236T) and their haplotype and the risk of breast cancer in Jordanian females. Materials and Methods: A case-control study involving 150 breast cancer cases and 150 controls was conducted. Controls were age-matched to cases. The polymerase chain reaction/restriction fragment length polymorphism (PCRRFLP) technique and sequencing were performed to analyse genotypes. Results: The distribution of MDR1 C3435T genotypes differed between cases and controls [cases, CC 45.3%, CT 41.3%, and TT 13.3%; controls, CC 13.4%, CT 43.3%, and TT 30.2%, p < 0.001]. Similarly, the distribution of G2677A/T significantly differed [cases, GG 43.1 %, GT+GA 50.9% and AA+TT 6%; controls, GG 29.6 %, GT+GA 50.9%, and AA+TT 19.4%, p = 0.004]. On the other hand, genotype and allelotype distribution of C1236T was not statistically different between cases and controls (p=0.56 and 0.26, respectively). The CGC haplotype increased the risk to breast cancer by 2.5-fold compared to others, while TGC and TTC haplotypes carried 2.5- and 5-fold lower risk of breast cancer, respectively. Conclusions: Genetic polymorphisms of MDR1 C3435T and G2677A/T, but not C1236T, are associated with increased risk of breast cancer. In addition, CGC, TGC and TTC haplotypes have different impacts on the risk of breast cancer. Future, larger studies are needed to validate these findings.     

Plasma 25-hydroxy vitamin D concentrations, vitamin D receptor genotype and breast cancer risk in a UK Caucasian population

Low levels of 25-hydroxy vitamin D (25(OH)D) and polymorphisms in the vitamin D receptor gene (VDR) have been found separately to increase risk of breast cancer. The aim of this study was to determine whether low 25(OH)D levels, alone and in combination with BsmI VDR genotype, increased breast cancer risk in a United Kingdom (UK) Caucasian population. Breast cancer patients (n=179) and control women (n=179) were recruited and 25(OH)D levels measured by enzyme-linked immunosorbent assay (ELISA). VDR genotype was determined by polymerase chain reaction (PCR) and restriction enzyme digest. Analysis showed that subjects with 25(OH)D levels <50 nM and the bb BsmI VDR genotype are 6.82 times more likely to have breast cancer than subjects with levels of 25(OH)D>50 nM and either the BB or Bb genotype (95% confidence interval (CI) 2.31-14.7, P<0.001). This study indicates that low levels of circulating 25(OH)D, both alone and in combination with BsmI VDR genotype, may increase risk of breast cancer in a UK Caucasian population.     

Association of polymorphisms of angiogenesis genes with breast cancer

BACKGROUND: Few studies have systematically explored a pathway approach: to test the association of multiple polymorphisms from multiple genes important to angiogenesis simultaneously with risk of breast cancer. We report our preliminary data evaluating the association of polymorphisms from seven genes known to influence angiogenesis with the likelihood of having breast cancer. METHODS: We recruited 715 controls and 520 subjects with breast cancer. Subjects provided a blood specimen and completed a questionnaire that included common breast cancer risk factors and breast cancer status. We evaluated candidate polymorphisms in the following genes: Hypoxia Inducible Factor-1 alpha (HIF1alpha), Vascular Endothelial Growth Factor (VEGF), VEGF Receptor 1 (VEGFR-1), VEGFR-2, endothelial Nitric Oxide Synthase (eNOS), Neuropilin-1 (NRP-1) and Neuropilin-2 (NRP-2). Testing for associations between each polymorphism and the presence or absence of breast cancer was performed. RESULTS: VEGF-2578 AA and -1498 CC genotypes were more common in cancer cases than controls (P = 0.06 and P = 0.04, respectively). These two genotypes remained significant predictors of breast cancer status after adjusting for non-genetic risk factors estimated by the Gail model (P = 0.03 and P = 0.03, respectively). When comparing women with invasive versus pre-invasive breast cancer, the eNOS-786 TT and eNOS 894 GG genotypes were associated with a greater likelihood of invasive disease and the eNOS 894 GG genotype was associated with a greater likelihood of having metastatic disease. CONCLUSION: There is an association of the VEGF-2578A and -1498C alleles with increased breast cancer risk. This association remains significant when adjusted for Gail score-related risk factors.     

Haplotype analysis of common vitamin D receptor variants and colon and rectal cancers.

Inherited variants of the vitamin D receptor (VDR) gene may influence cancer risk by altering the effect of vitamin D on cell growth and homeostasis. Studies have examined genotypes for common VDR polymorphisms, including a single nucleotide polymorphism (SNP) detected by Bsm1, a polyadenosine [poly(A)] repeat polymorphism, and a SNP detected by Fok1, as candidates for susceptibility to cancer, but most have not evaluated haplotypes for these markers. We investigated haplotypes for these polymorphisms in case-control studies of colon cancer (1,811 cases and 1,451 controls) and rectal cancer (905 cases and 679 controls). We used the expectation-maximization algorithm to estimate haplotypes for White, Hispanic, African-American, and Asian subjects, tested for differences in VDR haplotype distribution, and calculated odds ratios (OR) for association between haplotype and cancer. The distribution of haplotypes differed by race or ethnic group, but four common haplotypes accounted for the majority of alleles in all groups. VDR haplotype distributions differed between colon cancer cases and controls (P = 0.0004). The common haplotype bLF, containing Bsm1 b (Bsm1 restriction site present), poly(A) long (18-22 repeats), and Fok1 F (restriction site absent) was associated with increased risk of colon cancer, OR 1.15 (95% confidence interval, 1.03-1.28), as was the rare haplotype BLF, containing Bsm1 B (restriction site absent), poly(A) long, and Fok1 F (OR, 2.40; 95% confidence interval, 1.43-4.02). No case-control differences were detected for rectal cancer. In this analysis, haplotypes of the VDR influenced risk of colon cancer, but haplotype variables had only slightly better ability to explain case-control differences than genotype variables.     

Vitamin D receptor gene BsmI polymorphism correlates with erbB-2/HER-2 expression in human rectal cancer

Apart from the regulation of calcium metabolism, 1, 25-dihydroxyvitamin D(3) plays an essential role in cell proliferation and differentiation in several tissues. The vitamin D receptor (VDR) gene shows polymorphisms in humans that appear to be clinically significant in some pathological conditions. In the present study, the BsmI polymorphism of the VDR gene was studied in 59 Caucasian patients with rectal cancer (mean follow-up: 48 months). The relationship between VDR genotypes and the expression of oncogenes as well as their influence on survival were also investigated. VDR polymorphism was examined in tumor and normal mucosa cells by PCR technique. The expression of erbB-2/HER-2, p53, ras and epidermal growth factor receptor (EGFR) was also detected by immunohistochemistry and protein blotting. The presence of the VDR B allele significantly correlated with the overexpression of the erbB-2 oncogene. There was no difference in the VDR genotype between cancer and normal mucosal cells. Coexpression of erbB-2, pan-ras, p53 and EGFR internal and external domains was significantly higher in cancer cells than in normal mucosa. There was no significant correlation between VDR genotypes and age, gender, tumor infiltration depth, number and site of lymph node metastases and lymphatic or blood vessel infiltration. The VDR genotype alone did not influence survival. Overexpression of erbB-2 and EGFR was associated with a poor prognosis. In patients expressing only one oncogene in cancer cells, the presence of the VDR B allele showed a tendency to a poor prognosis. In conclusion, VDR gene BsmI polymorphism might affect the development and prognosis of rectal cancer by influencing erbB-2 oncogene expression.     

ATM基因多态性与乳腺癌患病风险及临床病理特征的相关性分析

目的:探讨共济失调毛细血管扩张突变基因（ataxia-telangiectasia mutated gene,ATM）单核苷酸多态性（SNP）rs189037和rs609261两个位点多态性与乳腺癌患病风险及临床病理特征的关系。方法:收集我院未接受放、化疗的乳腺癌根治标本和乳腺良性肿瘤标本。采用多重SNaPshot法检测ATM基因rs189037和rs609261两个位点多态性,分析其与乳腺癌患病风险及临床病理特征的关系。结果:ATM基因rs189037位点多态性与乳腺癌患癌风险及临床病理特征无关（GA基因型,P=0.667）;rs609261位点携带TC、CC基因型的淋巴结转移患者患癌风险高于TT基因型携带者（TC+CC显性模型,P=0.015）。ATM基因rs189037和rs609261两个位点等位基因频率和基因型分布与免疫组化指标（ER、PR、HER2、Ki-67）无相关性（rs189037位点GA+AA显性模型和rs609261位点TC+CC显性模型,ER:P=0.676、0.675;PR:P=0.758、0.573;HER2:P=0.203、0.327;Ki-67:P=0.189、0.405）。结论:ATM基因rs189037位点与乳腺癌患癌风险及临床病理特征、免疫组化指标无明显相关性。rs609261位点携带TC、CC基因型的淋巴结转移患者可能增加患病风险。     

Association of breast cancer progression with a vitamin D receptor gene polymorphism. South-East Sweden Breast Cancer Group.

The vitamin D3 receptor gene (VDR) contains a TaqI RFLP that is associated with increased VDR mRNA stability, increased serum levels of 1alpha,25-dihydroxyvitamin D3 (1,25-D3), and decreased risk for prostate cancer. Determination of the TaqI genotype, in a group of young women with breast cancer (n = 111; age, <37 years) and a control population (n = 130), revealed no overall association to risk for breast cancer. However, patients without TaqI site (TT genotype) showed a significantly increased risk for lymph node metastasis (relative risk, 1.8, 95% confidence interval, 1.3-2.6). Furthermore, a tendency toward an increased survival was found among estrogen receptor-positive, tamoxifen-treated patients who were homozygous for the TaqI site (P = 0.075). We conclude that polymorphism in the VDR gene may influence tumor progression and tamoxifen treatment response in early-onset breast carcinomas.     

Genetic variants at the miR-124 binding site on the cytoskeleton-organizing IQGAP1 gene confer differential predisposition to breast cancer

IQGAP1 knockout mice develop gastric cancer, but the IQGAP1 protein is associated with some advanced-stage human cancers. IQGAP1 expression is regulated by a microRNA, miR-124, through a binding site at the 3'-untranslated region, where a single nucleotide polymorphism (SNP) exists in the core binding region. We asked whether IQGAP1 expression is associated with breast cancer development and whether genetic variants at the miR-124 binding site are important. We genotyped the IQGAP1 SNP rs1042538 A/T in 1,541 breast cancer cases and 1,598 controls and analyzed the frequency of the variant and interactions with major risk factors in these populations. We also measured the expression of IQGAP1 at both mRNA and protein levels in different IQGAP1 genotypes. The IQGAP1 TT genotype, compared with the AA genotype, was associated with a significantly lower risk of developing breast cancer [P=0.049, odds ratio (OR), 0.78; 95% confidence interval (CI), 0.61-0.99]. In case-only analyses, the TT, compared with the AA, genotype was associated with progesterone receptor-positive subjects (OR, 1.35; 95% CI, 1.00-1.83). The expression levels of IQGAP1 protein were significantly higher in the TT genotype compated to the AA genotype. The presence of SNPs at the miR-124 binding site may be a marker for predicting breast cancer risk and prognosis.     

Circulating 25-Hydroxy Vitamin D Relative to Vitamin D Receptor Polymorphism after Vitamin D3 Supplementation in Breast Cancer Women: A Randomized,Double-Blind Controlled Clinical Trial

Objective: The influence of vitamin D receptor (VDR) genetic variation on serum 25-hydroxyvitamin D levels [25(OH)D] after vitamin D3 supplementation remains unclear. We aimed to investigate changes of 25(OH)D in a randomized, double-blind, placebo-controlled clinical trial, according to VDR genotype, after provision of vitamin D3 to breast cancer cases for a 2-month period. Methods: Participants were assigned to two treatment arms: placebo (n = 28) and vitamin D3 supplementation (n =28). The supplementation group received 50,000 IU of vitamin D every week for 2 months. Blood samples were collected at baseline and after intervention to measure serum 25(OH) D3. Genotypes were assessed for FokI, BsmI, ApaI, and TaqI polymorphisms. Results: After eight weeks supplementation, the rvention group showed a significant increase in the serum concentration of 25(OH) D3 (28±2.6 to 39±3.5; p=0.004). Subjects were then classified into twelve subgroups according to different VDR genotypes. Subjects with ff/Ff, TT/Tt, and Bb genotypes had significantly higher increases in serum 25(OH)D compared to those with FF, tt, and BB/bb genotypes post-intervention. Serum vitamin D3 levels with the AA genotype were lower than with aa/ Aa. No differences were found among other subgroups. Conclusion: Vitamin D3 supplementation increases serum 25(OH)D in women with breast cancer. Serum vitamin D3 in TT/Tt, ff/Ff, and Bb carriers was more responsive to vitamin D supplementation than in those with FF/ff and tt genotypes. Other subgroups might gain less from vitamin D3 supplementation.     

A polymorphism in the G protein β3-subunit gene is associated with bone metastasis risk in breast cancer patients

Breast cancer is the most frequently diagnosed cancer among women in western countries and bone metastases of breast cancer cause significant morbidity. G proteins are important components of a multitude of transmembrane receptors and are involved in the regulation of intracellular signaling pathways such as parathormone receptors 1 and 2 (PTH1 and 2), extracellular calcium-sensing receptor, the calcitonin receptor and the OPG/RANKL-system. A common polymorphism in the gene encoding the G protein β3-subunit, GNB3 825C > T, has been linked to increased G protein activation. To analyse the role of this polymorphism in bone metastasis of breast cancer, we determined GNB3 825C > T genotypes in 500 female breast cancer patients. According to breast cancer staging, patients were divided in three groups, representing patients without metastases (n = 250), those with metastases other than bone (n = 117), and those with bone metastasis (n = 133). Frequency of the GNB3 825 TT genotype was significantly lower among patients with bone metastases (3.1%) than among those with other metastases (12.8%; P = 0.004) or no metastases (13.3%; P < 0.001). In a Cox regression analysis, relative risk of the GNB3 TT genotype for bone metastasis was 0.22 (95% CI 0.08–0.61; P = 0.004) for bone metastasis. We conclude that the homozygous GNB3 825 TT genotype may be protective against development of bone metastasis in breast cancer patients. The precise mechanism for this remains to be determined, but could be due to a direct involvement of G protein-coupled receptors in bone metabolism.     

Angiotensin I-converting enzyme (ACE) gene polymorphism and breast cancer risk among Chinese women in Singapore

Angiotensin II has been shown to have possible mitogenic and angiogenic effects in human cell lines and animal models of breast cancer. It is converted from its precursor to its active form by the angiotensin I-converting enzyme (ACE). A recent epidemiological study observed lower breast cancer incidence in female users of ACE inhibitors relative to nonusers with comparable cardiovascular conditions. To study the hypothesis that reduced ACE activity is associated with reduced risk of breast cancer, we conducted a nested case-control study within the Singapore Chinese Health Study Cohort to investigate the associations between the ACE A-240T and I/D gene polymorphisms, and breast cancer risk. For this analysis, 189 incident breast cancer cases and 671 female cohort control subjects were compared. The low-activity A and I alleles were the putative "low-risk" alleles. The I/D and A-240T genotypes exhibited significant linkage disequilibrium among Singapore Chinese (contingency coefficient = 0.74; P < 0.001). With adjustment for breast cancer risk factors, women with one or two copies of the low activity A allele showed a statistically significant reduction in risk compared with those with the TT genotype [odds ratio (OR), 0.55; 95% confidence interval (CI), 0.34-0.90]. The risk reduction was enhanced after excluding subjects with medical conditions for which ACE inhibitors are commonly prescribed (OR, 0.49; 95% CI, 0.27-0.89). Comparable results were obtained with respect to the I/D genotype and risk of breast cancer. When the I/D and A-240T genotypes were considered simultaneously, compared with women with the high-activity genotypes (either TT or DD or both), those with the low-activity genotypes (presence of both A and I alleles) exhibited lower breast cancer risk (OR, 0.46; 95% CI, 0.27-0.81). Our findings support experimental data implicating ACE and angiotensin II in breast cancer, and suggest that the renin-angiotensin system may serve as a therapeutic target for breast cancer treatment and prevention.     

Genetic determinants of bone mass do not relate with breast cancer risk in US white and African-American women

Introduction The association between high bone mass and increased breast cancer risk has been established. Identification of polymorphisms and the resultant variant receptors suggests the possibility of differential effects on hormone responsive genes when complexed with the hormones. Both estrogen receptor-α (ER) and vitamin D receptor (VDR) polymorphisms have been associated with bone density. Thus, we examined these polymorphisms for association with increased breast cancer risk among US African-American and white women.Methods A case–control study was conducted to measure ER and VDR polymorphisms and radial bone mineral density (BMD) in African-American and white women, and to examine the association between polymorphisms, bone density and breast cancer risk. Genotypes and bone density were obtained from 412 women (220 cases and 192 controls, with equal distribution between the two ethnic groups).Results We found no evidence for an association between either the ER or VDR genotypes and breast cancer risk. Also, there was no difference in the risk of breast cancer by genotypes after adjusting for ethnicity. The addition of age, sex and ethnicity-specific BMD (Z-scores) did not significantly change the odds ratio for breast cancer.Conclusions Our data suggest that the polymorphisms investigated had no effect on risk of breast cancer in this population. Thus, we found no evidence to support our hypothesis that breast cancer cases and controls would have a different distribution of ER and VDR genotypes. Furthermore, the polymorphisms were not associated with differences in bone mass and its relationship with breast cancer risk.     

Association of ApaI and TaqI polymorphisms in VDR Gene with Breast Cancer

Background: Vitamin D inhibits cell proliferation via the vitamin D receptor (VDR), which may affect breast cancer risk. This study aimed to investigate the association of ApaI and TaqI polymorphisms of the VDR gene with breast cancer risk which followed by stratified analysis. Materials and methods: A case-control study was conducted on 150 breast cancer patients and 150 healthy controls. VDR ApaI and TaqI genotyping were performed by PCR-RFLP. Some demographic and pathologic features of patients were extracted from their archived files and then were analyzed by genotypes distributions. Results: For ApaI polymorphism, our data showed a significant difference between the patient and healthy groups for mutant allele carriers compared with those with AA genotype. Besides, statistical analysis showed that there was a significant association between the C allele and the increased risk of breast cancer. For TaqI polymorphism, statistical analysis revealed that there was a significant association between CC genotype and increased risk of breast cancer. Also, there was a significant association between the C allele and the increased risk of breast cancer. In a preliminary study, stratified analysis based on the size of tumor and lymph node metastasis revealed no significant association between two ApaI and TaqI variations and these parameters. Conclusions: Based on our results, the VDR ApaI and TaqI variations could be considered as genetic risk factors for breast cancer. However, further studies with a larger sample size are required to obtain more accurate outcomes, especially in stratified analysis.     

An investigation of relationships between hypoxia-inducible factor-1 alpha gene polymorphisms and ovarian, cervical and endometrial cancers

BACKGROUND: DNA sequence variations in HIF-1 alpha gene might yield changes both in the production outcomes and in the activities of the gene. Overexpression of the HIF-1 alpha subunit, resulting from intratumoral hypoxia and genetic alterations, has been demonstrated in common human cancers and is correlated with tumor angiogenesis and patient mortality. In this study, we aimed to determine how the three single nucleotide polymorphisms (SNPs, C1772T and G1790A exon 12, C111A exon 2) in the HIF-1 alpha gene coding regions affect the ovarian, cervical and endometrial cancer patients in the Turkish population. A study on this relationship has not been conducted to date. METHOD: 102 gynecologic cancer patients and 107 healthy controls were studied. Genotypes of the three polymorphisms were analyzed by PCR-RFLP. RESULTS: There was no significant difference between ovarian cancer patients and controls in terms of the distribution of C1772T genotypes and alleles (P>0.05). However, there was a highly significant increase in the frequency of both CT 1772 and TT 1772 genotypes in patients with cervical and endometrial cancers compared with healthy controls. In fact, 1772T allele-carriers (CT+TT genotypes) showed an association with the risk of cervical and endometrial cancers compared to the wild type (OR=3.84, 95% CI: 1.65-8.93; OR=7.41, 95% CI: 2.33-23.59, respectively). C1772T polymorphism was not associated with family history concerning gynecologic and/or other cancer types, stages (I-IV) and grades of tumor, smoking habits and existence of other diseases that generate a hypoxic microenvironment even after multivariable logistic regression analysis. As for HIF-1 alpha G1790A genotypes, the frequencies of G alleles were 98% in ovarian patients and 100% in the control group. We found no significant difference in the genotype distribution and allele frequencies between the ovarian patients and healthy control subjects. There were no GA and AA genotypes among the cervical and endometrial cancer patients. As for HIF-1 alpha C111A polymorphism, we did not find CA and AA variants of the gene in controls or in any of the three types of patients. CONCLUSION: Our results suggest that the C1772T polymorphism of the HIF-1 alpha may be associated with cervical and endometrial cancers.     

Functional variants in the promoter of interleukin-1beta are associated with an increased risk of breast cancer: a case-control analysis in a Chinese population

Interleukin 1beta (IL-1beta) is a multifunctional cytokine that upregulates the inflammatory response, and participates in carcinogenesis, malignant transformation, tumor growth, invasion and metastasis. Two potentially functional polymorphisms (T-31C and C-511T) in the IL-1beta gene promoter were suggested to be correlated with alteration of IL-1beta expression and therefore may be associated with cancer risk. To test the hypothesis that these 2 polymorphisms are associated with risk of breast cancer, we performed a case-control study of 365 breast cancer cases, 270 patients with benign breast diseases (BBD) and 631 cancer-free controls in a Chinese population. Multivariate logistic regression analyses revealed that increased risk of breast cancer was associated with IL-1beta-31C variant genotypes [adjusted odds ratio (OR)=1.28 and 95% confidence interval (CI)=0.91-1.80 for -31CT and 1.72 (95% CI=1.16-2.54) for -31CC], compared with the -31TT genotype. Similarly, IL-1beta-511T variant genotypes were also associated with increased risk of breast cancer (adjusted OR=1.20, 95% CI=0.86-1.67 for -511CT and adjusted OR=1.74, 95% CI=1.18-2.56 for -511TT), compared with the -511CC genotype. Furthermore, cancer risks associated with IL-1betaT-31C variant genotypes were more evident in older women, postmenopausal women and individuals with a later menarche age. Interestingly, although we did not find significant associations of these 2 variants with cancer risk when compared with the BBD patients, a 1.27-fold (95% CI=1.01-1.60) increased risk was observed with the -31C-511T common haplotype. These findings indicate that these 2 IL-1beta promoter variants may contribute to risk of developing breast cancer in the Chinese population.