Association of polymorphisms in TP53 and the promoter region of IL10 with gastric cancer in a Kazakh population.

The emerging evidence indicates that single nucleotide polymorphisms (SNPs) of the tumor necrosis factor (TNF), interleukin 10 (IL10), tumor protein p53 (TP53), and cluster of differentiation 14 (CD14) genes may determine individual susceptibility to gastric cancer (GC). We aimed to investigate the associations for polymorphisms of the TNF, IL10, TP53, and CD14 genes in a population of Kazakhs, to identify potential risk or protective associations of the SNPs with GC. A case group of 143 patients hospitalized for GC was enrolled. Controls were 355 volunteers with no history of any cancer and frequency matched with cases by age. Differences in proportions for categorical variables and the assessment of genotypic frequencies conforming to the Hardy-Weinberg equilibrium law were evaluated by the Chi-square test. Associations between genetic polymorphisms and the risk of GC were estimated by regression analysis. For genetic analysis, three genetic models (additive, dominant, and recessive) were used. Four significant associations were found. The SNPs rs1042522 of TP53 and rs1800896 of IL10 were risk factors for GC by the additive model. Two polymorphisms of IL10 were protective of GC, namely, rs1800872 by additive model and rs1800871 by recessive model. No significant associations were observed between the TNF and CD14 polymorphisms and GC. The polymorphisms TP53 rs1042522 and IL10 rs1800896 are associated with GC risk, while the polymorphisms IL10 rs1800872 and rs1800871 are protective of GC in the population of Kazakhs.

PTH Gene Polymorphism and Breast Cancer Risk in Kazakhstan.

INTRODUCTION: Breast cancer is the most common type of cancer among women. In Kazakhstan, breast cancer holds first place among causes of women death caused by cancer in the 45-55 year age group. Many studies have shown that the risk of acquiring breast cancer may be related to the level of calcium in the blood serum. One of the important regulators of calcium metabolism in the body is the parathyroid hormone. Single nucleotide polymorphisms in the gene encoding the parathyroid hormone (PTH) are associated with breast cancer development risk, and may modify the associative interaction between the levels of calcium intake and breast cancer. Experimental studies have shown that PTH gene has a carcinogenic effect. At least three studies showed a weak positive correlation between the risk of acquiring breast cancer and primary hyperparathyroidism, a state with high levels of PTH and often high levels of calcium. The aim of this investigation was to evaluate potential association between PTH gene polymorphism and breast cancer risk among Kazakhstani women. METHODS: Female breast cancer patients (n = 429) and matched control women (n = 373) were recruited into a case - control study,. Genomic DNA was extracted from peripheral venous blood of study participants using Wizard® Genomic DNA Purification Kit (Promega, USA). Detection of PTH gene polymorphism (rs1459015) was done by means of the TaqMan® SNP Genotyping Assay of real-time PCR. Statistical analysis was conducted using SPSS 19.0. RESULTS: PTH gene alleles were in Hardy-Weinberg equilibrium (p > 0.05). Distribution was 59% CC, 35% CT, 6% TT in the group with breast cancer and 50% CC, 43% CT, 6% TT in the control group. Total difference (between the group with breast cancer and the control group) in allele frequencies for PTH polymorphism was not significant (p > 0.05). No association was found between rs1459015 TT and breast cancer risk (OR = 1.039; 95%, CI 0.740 - 1.297; p = 0.893). CONCLUSION: We found no association between PTHrs1459015 polymorphism and breast cancer in our present study. Further studies are required to confirm our results and clarify role of PTH gene genotypes on breast cancer risk.

Vitamin D Receptor Gene Polymorphisms and Breast Cancer Risk in Kazakhstan.

INTRODUCTION: The steroid hormone 1,25-dihydroxyvitamin D3 is thought to protect against breast cancer. The activity of 1,25-dihydroxyvitamin D3 is 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. Two common single nucleotide polymorphisms (SNP) in the VDR gene (VDR), rs1544410 (BsmI) and rs2228570 (FokI), have been inconsistently associated with breast cancer risk. Increased risk has been reported for the FokI ff genotype, which encodes a less transcriptionally active isoform of VDR. A reduced risk has been reported for the BsmI BB genotype which may influence VDR mRNA stability. AIM: We have investigated whether specific VDR gene polymorphisms are associated with breast cancer risk in Kazakhstan women. MATERIAL AND METHODS: In a case-control study, female breast cancer patients (315) and a female control group (n=604) were tested for two VDR polymorphisms. Statistical analysis was conducted using SPSS19.0. RESULTS: : The VDR rs2228570 (FokI) polymorphism was associated with an increased occurence of BC [rs2228570 (folk) ff vs. FF genotype: OR=1.71; 95% CI=1.21-2.43]. No association was noted between rs1544410 (BsmI) BB and breast cancer risk [OR=0.68; 95% CI=0.49-0.95]. CONCLUSION: : Although the factors that increase breast cancer susceptibility remain uncertain, future large studies should integrate genetic variation in VDR with biomarkers of vitamin D status. Additional testing on the effect of varying genotypes on the functional mechanisms of the VDR could help to improve future testing and treatment of woman at risk for breast cancer.