Armaghane Danesh Bimonthly Journal (Nov 2019)
Association of MCC Rs9122 Polymorphism with Increased Risk of Gastric Cancer
Abstract
Background & aim: Gastric cancer is one of the most common malignancies worldwide. Genetic background has been identified as one of the risk factors for gastric cancer. One of the genes that have been proven to play a role in various cancers, including gastric cancer, is the MCC gene. There are hundreds of SNPs in the coding and regulatory region of the MCC gene, one of which is rs9122, which is located at the junction of several microRNAs. The aim of the present study was to determine the relationship between MCC gene rs9122 polymorphism and gastric cancer risk. Methods: In this case-control study, blood or DNA samples were collected from 214 gastric cancer patients diagnosed by a gastroenterologist and endoscopic test, and 211 healthy control individuals, from the Biobank of Shiraz Cancer Research Center, with no gastrointestinal disease, based on a gastroenterologist and the endoscopy results. Also in control group, Helicobacter pylori infection test was negative and this group was matched for gender, age and geographical area with patients. After extracting genomic DNA from blood samples, MCC rs9122 polymorphism genotype was determined using RFLP PCR- (MluI enzyme) technique. The association of this polymorphism with gastric cancer susceptibility was evaluated using SPSS software and logistic regression test. Results: The results indicated that the frequency of A allele and G allele in control group were 48.1 and 51.9% and the frequency of AA, AG and GG genotypes in this group were 27, 42.2 and 30.8 respectively. In the patient group, the frequency of A and G alleles were 40.7 and 59.3, and the frequencies of AA, AG and GG were 23.4%, 34.6% and 42%, respectively. The GG genotype also borderline increased the risk of gastric cancer (p=0.071, OR= 1.557, 95% CI=0.961-2599) and G allele as a risk allele, susceptibility to Increases gastric cancer (p=0.029, OR=1.353, 95% CI = 1.031-1.775). In addition, the GG genotype increased the risk of gastric cancer compared with the total AA + AG genotypes (OR = 1.630, p = 0.016, 95% 1.94-0.242 / 429 CI), whereas total AG + GG genotypes were not associated with risk of gastric cancer (p = 0.386). Conclusion: MCS rs9122 polymorphism seems to be associated with gastric cancer risk, so that the G allele and GG genotype at this locus increase the risk of gastric cancer. Confirming these findings in larger populations, geographically and ethnically diverse, can be used to screen for gastric cancer.
