miR-520a靶基因PIK3CA结合位点多态性与中国汉族人群大肠癌易感性的关联研究

摘要

Background and purpose: Increasing evidence has indicated that polymorphisms in the microRNA (miRNA, miR) binding site of target gene can alter the ability of miRNA and modulate the risk of cancer. We aimed to investigate the association between a miR-520a binding site single nucleotide polymorphism (SNP) rs141178472 in the PIK3CA 3’UTR and the risk of colorectal cancer in a Chinese Han population. Methods:The polymorphism rs141178472 was analyzed in a case-control study, including 386 colorectal cancer patients and 394 age-and sex-matched controls. The relationship between the polymorphism and the risk of colorectal cancer was examined by statistical methods. Results:Individuals carrying the rs141178472 CC genotype or C allele had an increased risk of developing colorectal cancer (CC vs TT, OR=1.716, 95%CI:1.084-2.716, P=0.022;C vs T, OR=1.258, 95%CI:1.021-1.551, P=0.033). Furthermore, the expression of PIK3CA was detected in the peripheral blood mononucleated cell of colorectal cancer patients, suggesting that mRNA levels of PIK3CA might be associated with SNP rs141178472. Conclusion:These ifndings provide evidence that a miR-520a binding site polymorphism rs141178472 in the PIK3CA 3’UTR may play crucial roles in the etiology of colorectal cancer.%背景与目的：越来越多的研究表明，微小RNA(microRNA，miRNA，miR)靶基因位点的多态性可能会影响miRNA的转录或生成能力，影响个体对肿瘤的易感性。本研究旨在探讨大肠癌患者miR-520a靶基因PIK3CA 3’端单核苷酸多态性(single nucleotide polymorphism，SNP)位点rs141178472与中国汉族人群大肠癌易感性之间的关系。方法：选取386例大肠癌标本作为实验组，394名年龄及性别比例匹配的非肿瘤个体作为对照组。病例对照研究检测rs141178472的分布频率。统计分析大肠癌易感性与多态性之间的关系。结果：携有rs141178472 CC基因型或C等位基因显著增加了大肠癌的发病风险(CC vs TT，OR=1.716，95%CI：1.084~2.716， P=0.022；C vs T，OR=1.258，95%CI：1.021~1.551，P=0.033)。通过检测大肠癌患者外周血单个核细胞PIK3CA的表达发现，PIK3CA mRNA的表达与SNP基因型rs141178472具有关联性。结论：miR-520a与PIK3CA 3’UTR的SNP位点rs141178472相互作用可能与大肠癌易感性有关。