Dataset Information

Association of Vitamin D Receptor Gene Polymorphisms with Colorectal Cancer in a Saudi Arabian Population.

ABSTRACT: BACKGROUND:Vitamin D, causally implicated in bone diseases and human malignancies, exerts its effects through binding to the vitamin D receptor (VDR). VDR is a transcription factor modulating the expression of several genes in different pathways. Genetic variants in the VDR gene have been associated with several cancers in different population including colorectal cancer. OBJECTIVE:To assess the association of VDR gene polymorphisms in relation with colorectal cancer (CRC) in a Saudi population. METHODS:The polymorphisms of VDR gene (BsmI, FokI, ApaI and TaqI) were analyzed by the polymerase chain reaction amplification of segments of interest followed by Sanger sequencing. One hundred diagnosed CRC patients and 100 healthy control subjects that were age and gender matched were recruited. RESULTS:We did not observe significant association of any of the four VDR polymorphisms with colorectal cancer risk in the overall analysis. Although not statistically significant, the AA genotype of BsmI conferred about two-fold protection against CRCs compared to the GG genotype. Stratification of the study subjects based on age and gender suggests statistically significant association of CRC with the 'C' allele of ApaI in patients >57 years of age at disease diagnosis and BsmI polymorphism in females. In addition, statistically significant differences were observed for the genotypic distributions of VDR-BsmI, ApaI and TaqI SNPs between Saudi Arabian population and several of the International HapMap project populations. CONCLUSION:Despite the absence of correlation of the examined VDR polymorphisms with CRCs in the combined analysis, ApaI and BsmI loci are statistically significantly associated with CRC in elderly and female patients, respectively. These findings need further validation in larger cohorts prior to utilizing these SNPs as potential screening markers for colorectal cancers in Saudi population.

SUBMITTER: Alkhayal KA

PROVIDER: S-EPMC4911096 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Association of Vitamin D Receptor Gene Polymorphisms with Colorectal Cancer in a Saudi Arabian Population.

Alkhayal Khayal A KA Awadalia Zainab H ZH Vaali-Mohammed Mansoor-Ali MA Al Obeed Omar A OA Al Wesaimer Alanoud A Halwani Rabih R Zubaidi Ahmed M AM Khan Zahid Z Abdulla Maha-Hamadien MH

PloS one 20160616 6

<h4>Background</h4>Vitamin D, causally implicated in bone diseases and human malignancies, exerts its effects through binding to the vitamin D receptor (VDR). VDR is a transcription factor modulating the expression of several genes in different pathways. Genetic variants in the VDR gene have been associated with several cancers in different population including colorectal cancer.<h4>Objective</h4>To assess the association of VDR gene polymorphisms in relation with colorectal cancer (CRC) in a Sa ...[more]

PMID: 27309378

Similar Datasets

Project description:Background:Inflammation is a fundamental factor that contributes to the development and progression of several types of cancer including colon cancer. Toll-like receptors (TLRs) and their signaling pathways have been reported to be associated with chronic inflammation and thereby induced cancer. Our aim was to investigate the expression and polymorphisms of TLR2 and their association with colon cancer. Methods:Real-time PCR and immunohistochemistry were used to investigate TLR2 gene expression and to evaluate the potential risk of predisposition to colon cancer caused by three tagging single-nucleotide polymorphisms (SNPs) on TLR2, including rs3804100, rs4696480, and rs3804099. TaqMan assay was conducted on samples from 115 patients with colon cancer and 102 age- and sex-matched normal individuals. Results:We found that, TLR2 was highly expressed in epithelial colon cancer cells and both TLR2 mRNA and protein levels, and significantly decreased in tumor tissues compared to normal tissues. Two of three TLR2 SNPs increased the risk of colon cancer. However, TLR2 rs3804099 increased the risk of colon cancer development by more than 3.8- and 5-fold in female patients and patients aged less than 57 years, respectively. The T allele of TLR2 rs3804100 showed a significant association with patients less than 57 years. In silico analysis of the TLR2 nucleotide substitution in SNP rs3804100 and rs3804099 determined that 67% and 70% probability of these single nucleotide variants alter splicing phenotypes, rs3804100 more specifically result on activating an additional splice site. Genotype and allele frequencies of rs4696480 were similar between the overall study populations. Thus, TLR2 rs4696480 appear to be not involved in colon cancer in our study population. Conclusions:There was a significant link between innate immunity deregulation through disruption of the TLRs and potential development of colon cancer. These SNPs can be used as screening markers for predicting colon cancer risk earlier in life to implement necessary prevention.

Project description:Vitamin D and its cognate intracellular nuclear receptor, namely, vitamin D receptor (VDR), are involved in the regulation of a variety of body metabolic processes, immune function, and oncogenesis. A large number of studies demonstrated the association of low vitamin D levels and variations in five common single nucleotide polymorphisms (SNPs), FokI, BsmI, Tru9I, ApaI, and TaqI, with the risk of several cancers, including colorectal cancers. However, these associations vary among different populations. This case-control study was aimed at analysing whether common single-nucleotide polymorphisms (SNPs) and haplotypes of the vitamin D receptor (VDR) gene contribute to colorectal carcinogenesis in the Thai population. We enrolled 364 Thai participants from King Chulalongkorn Memorial Hospital between 2014 and 2015. Half of the participants underwent colonoscopy and showed a normal colon without polyps (control group) and another half were newly diagnosed patients with colorectal cancer (CRC) by colonoscopy during the index period, were under treatment, or were followed up at the outpatient clinic (case group). Differences in allele and genotype frequencies of five common VDR SNPs, between the case and control groups, were the primary outcome measures. Differences in haplotype frequencies of the five SNPs between the case and control groups were the secondary outcome measures. Among the 364 participants, baseline characteristics were not significantly different between the case and control groups, except for the higher proportion of males in the CRC group. The mean vitamin D level was also not significantly different between the case and control groups (24.6 ± 9.1 vs. 25.3 ± 10.6 ng/mL, p = 0.52). None of the five VDR SNPs was associated with CRC development (p > 0.05). However, haplotype analysis of these polymorphisms demonstrated that the AGGT haplotype was associated with a decreased risk of CRC (odds ratio 0.24, 95% confidence interval 0.07-0.81, p = 0.01). The AGGT haplotype was associated with a lower risk of CRC in the Thai population. This genetic linkage might support the role of vitamin D in colorectal carcinogenesis. However, this finding requires further study within a larger population and a multivariate analysis of other established risk factors.

Dataset Information

Association of Vitamin D Receptor Gene Polymorphisms with Colorectal Cancer in a Saudi Arabian Population.

Publications

Association of Vitamin D Receptor Gene Polymorphisms with Colorectal Cancer in a Saudi Arabian Population.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets