Search

Genetic polymorphisms are responsible for inter-individual variation and diversity and have been recently considered as the main genetic elements involved in the development and progression of cancer. We examined associations between common germline genetic variants in 7 genes involved in folate metabolism, cell proliferation and apoptosis, prostaglandin synthesis, detoxification of compounds and inflammation, and disease-free survival among women diagnosed with invasive breast cancer. DNA from up to 432 women was genotyped for 8 polymorphisms. The genotypes of each polymorphism were tested for association with disease-free survival using univariate and multivariate Cox regression analysis. The model was adjusted for known breast cancer prognostic factors. The rare allele of the IL-10 592C>A polymorphism was significantly associated with reduced disease-free survival (P = 0.018, risk ratio of recurrence (RR) = 1.45, 95% confidence interval (CI) = 1.06-1.98), which was not attenuated after adjusting for age at diagnosis, tumor size, lymph node status, clinical stage, histological grade, estrogen receptor status, progesterone receptor status, and treatment modalities (P = 0.019, RR = 1.48, 95% CI = 1.066-2.044). No association was found between MTHFR 677C>T, TGFB1 29T>C, FASLG 844C>T, FAS 1377G>A, FAS 670A>G, PTGS2 8473T>C and SULT1A1 638G>A polymorphisms and disease-free survival. Our data suggest that the rare allele of IL-10 592C>A may be a potential prognostic marker in breast cancer for disease-free survival.

Purpose: Vascular endothelial growth factor (VEGF) is a key regulator of tumor-induced angiogenesis and is required for growth of tumors. We tested the hypothesis that VEGF gene polymorphisms may be associated with breast cancer., Experimental Design: We performed a case-control study including 804 female incident breast cancer patients and 804 female age-matched healthy control subjects. We selected seven VEGF candidate polymorphisms and determined genotypes by 5'-nuclease (TaqMan) assays. Furthermore, VEGF plasma levels and genotypes were analyzed in a group of 81 healthy volunteers (64 men and 17 women)., Results: Haplotype analysis showed two separate blocks of high-linkage disequilibrium, formed by five polymorphisms upstream of the coding sequence (promoter and 5' untranslated region) and two polymorphisms downstream of the coding sequence. None of the single polymorphisms or haplotypes was significantly associated with the presence of breast cancer. After Bonferroni correction for multiple testing, only one statistical signifcant association between VEGF genotypes and haplotypes and tumor characteristics was observed (-634C allele and small tumor size; p < 0.001). In a multivariate regression analysis including sex, age, VEGF genotypes, and haplotypes as covariates and VEGF plasma level as dependent variable, none of the VEGF polymorphism or haplotypes was a significant predictor of VEGF plasma levels., Conclusions: Our findings do not support the hypothesis that VEGF polymorphisms are associated with breast cancer risk. The association of the VEGF -634C allele with small tumor size is in clear contrast to a previous publication and should be interpreted with caution until replicated by additional studies.

In the biology of complex disorders, such as breast cancer, interactions among genetic factors may play an important role and theoretical considerations suggest that gene-gene interactions are quite common in such diseases. In this case-control study with 500 breast cancer patients and 500 population-based healthy sex- and age-matched control subjects, we applied a multigenic approach to examine the associations with breast cancer risk of a comprehensive panel of 16 selected polymorphisms in a variety of pathways using classification tree analysis (CART). Overall, 79.6% of all breast cancer patients and 80.6% of all control subjects were correctly classified on the basis of their individual genetic profile by the classification procedure. CART analysis of the data identified the heterozygous vascular endothelial growth factor (VEGF) and matrix metalloproteinase 3 (MMP3) genotype and homozygous cyclooxygenase-2 (PTGS2) mutant as the initial splits, indicating that these genotypes exert the greatest impact on the classification process. Breast cancer patients were primarily indicated by 30 distinct genetic profiles. The odds ratio of these genetic risk profiles for breast cancer was 16.12 (95% confidence interval 11.09-23.49). Five genetic profiles formed homogenous breast cancer subgroups and represented highest risk genetic profiles. This is the first comprehensive study to use a multigenic analysis for breast cancer and the data suggest that individuals with distinct genetic profiles are at an increased risk for breast cancer, confirming the importance of taking a multigenic approach for risk assessment.

Integrins are cell surface receptors, which mediate cell-to-cell and cell-to-extracellular matrix adhesion. Some of them, e.g. alpha(V)beta(3), alpha(IIb)beta(3) and alpha(2)beta(1), have been suggested as key players for cancer development and tumor metastasis. Two polymorphisms in the gene for the alpha(2) component, ITGA2 807C>T and 1648G>A, have been associated with the cell-surface density of integrin alpha(2)beta(1). The 176T>C polymorphism in the ITGB3 gene, encoding the beta(3) subunit of integrins alpha(IIb)beta(3) and alpha(V)beta(3), modifies a variety of traits of beta(3) expressing cells. To analyze the role of ITGA2 and ITGB3 polymorphisms for breast cancer risk and prognosis, we performed a case-control study including 500 female breast cancer patients and 500 healthy female age-matched control subjects. All study participants were of Caucasian origin (Austria, Middle-Europe). The ITGA2 1648&#95;AA genotype was significantly associated with breast cancer (odds ratio 3.12; 95% confidence interval 1.11-8.77). Carriers of the most common ITGA2 haplotype (807C&#95;1648G, 'wildtype') were at decreased risk for breast cancer (odds ratio 0.72; 95% confidence interval 0.53-0.98). A histological grade of 3 or 4 was found more often in ITGA2 807TT subjects (p=0.039 compared to CC+CT genotypes) and carriers of an ITGA2 1648A allele (p=0.017 compared to GG genotype). Carriers of the ITGA2 807C&#95;1648G haplotype were less likely to have a histological grade 3 or 4 compared to non-carriers (p=0.003). The ITGB3 176T>C polymorphisms was not associated with breast cancer susceptibility. In a Cox-regression analysis, carriers of the homozygous ITGB3 176-CC genotype had a higher risk for metastasis (relative risk 2.3; 95% CI 1.3-4.2; p=0.005). We conclude that functional polymorphisms in integrin genes ITGA2 and ITGB3 influence the development and progression of breast cancer, respectively. The precise mechanism remains to be determined, but likely involves dysregulated signaling pathways.

Interleukin-10 (IL-10) is an immunosuppressive cytokine which may facilitate development of cancer by supporting tumor escape from the immune response. A [TCATA] haplotype formed by polymorphisms at positions -3575, -2763, -1082, -819 and -592 in the promoter of the IL-10 gene is a strong determinant for IL-10 expression. The presence of this haplotype can be determined by analysis of the -592C > A polymorphism. Aim of the present study was to analyze the role of the IL-10 [TCATA] haplotype for breast cancer. We performed a case-control study including 500 female patients with histologically confirmed breast cancer and 500 female, age-matched, healthy control subjects from population-based screening studies. The -592C > A polymorphism was determined by a 5'-nuclease assay (TaqMan). Frequency of the homozygous -592 AA genotype, indicating homozygosity for the [TCATA] haplotype, was 4.2% among patients and 7.3% among controls (p=0.038; odds ratio 0.56; 95% confidence interval 0.32-0.97). IL-10 genotypes were not associated with tumor size, histological grading, estrogen or progesterone receptor status and age at diagnosis. Therefore we conclude that the IL-10 -592C > A promoter polymorphism may be associated with a reduced breast cancer risk.

Background: Positron emission tomography (PET) is a an important technology for detection and staging of breast cancer. The method is based upon assessment of glucose metabolism using the 18F-fluorodeoxyglucose (18F-FDG) as glucose analog. A strong variability of 18F-FDG uptake by breast cancer tissue has been reported, the reason for which is not fully understood but may involve vascular density and integrity. A 936C>T polymorphism in the gene for the vascular endothelial growth factor (VEGF) has been associated with VEGF plasma levels and breast cancer risk., Methods: To analyze the role of this polymorphism for 18F-FDG uptake in breast cancer patients, we determined the VEGF genotype in 37 patients in whom PET was performed for detection of metastases. An 18F-FDG uptake score of 1 (low uptake), 2 (medium uptake) or 3 (high uptake) was assigned to each patient., Results: VEGF CC, CT and TT genotypes were found in 28, 8 and 1 patient. Uptake score of 1 was found in three patients, score 2 in 12 patients and score 3 in 22 patients. VEGF genotype was significantly associated with FDG uptake score (chi2 test, p=0.007). The number of 936-T alleles correlated with a lower 18F-FDG uptake score (Spearman correlation test, p=0.032)., Conclusion: In the present study the common VEGF 936C>T polymorphisms had a major impact on 18F-FDG uptake in breast cancer patients. If this result can be confirmed in following studies, it might have strong relevance for the use of PET as diagnostic tool.

Sulfotransferase 1A1 (SULT1A1), also designated as phenol-preferring sulfotransferase, is involved in the bioactivation and detoxification of a variety of potential carcinogens, including iodothyronines, hydroxylated aromatic amines, and phenolic xenobiotics. A common arginine (R) to histidine (H) polymorphism at amino acid position 213 influences SULT1A1 activity and has been suggested as risk factor for a different types of cancers. To investigate the role of this polymorphism for breast cancer risk, SULT1A1 genotype was determined in 500 women with clinically verified breast cancer and 500 female age-matched healthy control subjects. Frequencies of heterozygous (controls: 42.5% patients: 50.2%) or homozygous (controls: 12.6%; patients: 9.4%) carriers of the 213H variant were not significantly different between groups. The SULT1A1 genotype was furthermore not associated with tumor size, histological grading, estrogen or progesterone receptor status and age at diagnosis. The SULT1A1 213H variant was associated with the presence of lymph node metastases (p = 0.002). We conclude that the SULT1A1 R213H polymorphism is not a general risk factor for breast cancer, but may be involved in lymph node metastazing in breast cancer patients.

A common 870G > A polymorphism in the gene for cyclin D1, CCND1, has been linked to alternative splicing and cancer susceptibility. To analyze its role for breast cancer, we determined the CCND1 genotype in 500 breast cancer patients and 500 controls. CCND1 genotype frequencies were similar among patients and controls. The CCND1 genotype was furthermore not associated with tumor characteristics. We conclude that the CCND1 870G > A polymorphism is not associated with breast cancer.

Methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism and plays a role in DNA biosynthesis, methylation, and repair in actively dividing cells. A common 677C>T polymorphism in the gene for MTHFR, leading to a thermolabile enzyme with decreased activity, has been associated with reduced plasma folate levels and elevated homocysteine levels and could be a risk factor for breast cancer. In the present case-control study, MTHFR genotype was determined in 500 women with clinically verified breast cancer and 500 female age-matched healthy control subjects. The homozygous TT genotype was found in 13.0% patients and 13.1% controls (P = n.s.). The odds ratio of TT homozygotes for breast cancer was 0.99 (95% confidence interval 0.68-1.43). The MTHFR genotype was furthermore not associated with tumor size, histological grading, estrogen or progesterone receptor status and age at diagnosis. In a subgroup of 116 premenopausal patients, no increased frequency of the homozygous 677T genotype was found (13.8%). Therefore, we conclude that the MTHFR 677C>T polymorphism is not associated with individual susceptibility to breast cancer.