Research On Relationship Between MiRNA Regulation And3’UTR Genetic Polymorphisms Of Colorectal Cancer Candidate Gene TGFBR1and CD4

microRNA (miRNA) are single-stranded non-coding RNA molecules encoded by endogenous gene with a length of about21-25nucleotides, and work as post-DNA transcription regulators for gene expression. miRNA could result in the mRNA degradation of target gene or inhibiting mRNA translation by specifically binding to the3’UTRs or open reading frame of the target gene. Many studies have shown that single nucleotide variation/polymorphisms chromosomely play an important role in the transcription, formation, exportation and regulation of miRNA. It has been confirmed SNPs of target genes are associated with risk of colorectal cancer, breast cancer, stomach cancer, esophageal cancer and thyroid cancer etc, as well as the prediction of nasopharyngeal carcinoma recurrence after radiotherapy.Globally, colorectal cancer is the third most common malignancy. In China, cancer ranks first in the mortality of major diseases, and colorectal cancer ranks fifth among the most harmful cancer. Current studies revealed that SNPs that miRNA target on are related to colorectal cancer (CRC) risk based on case-control studies. However the in-depth studies of target gene involved in the disease occurrence and development remain insufficiency, therefore revealing the relationship between miRNAs and their target genes is the key to the research. In this project, bioinformatics software are applied to analyze the3’UTR of CRC related candidate genes, identifying rs868, rs420549(TGFBR1) and rs3213427(CD4) might be miRNA targeted binding sites. To analyze the regulatory role of SNPs on specific miRNA, we constructed dual-luciferase reporter gene expression vectors which contain3’UTR wild-type or mutant-type of candidate gene, and further to determine the role that mutation site-mediated change of regulation level in gene function; And initially identified functional genetic markers for CRC risk warning. Our results showed that:the optimal concentration of mimics is100nM with transfection efficiency about70%, the mimics are then co-transfected with pmirGLO-target gene (wt/mut) in Hela cells; Utilizing dual luciferase reporter gene screening, we initially identified recombinant that contains A allele of TGFBR13’UTR or T allele of CD43’UTR reduced the luciferase activity after co-transfecting with miR-98or miR-921, respectively.The results of this study indicated that there was a target regulatory relationships between TGFBR1and has-miR-98,CD4and has-miR-921.However,whether they are involved in the regulation of colorectal cancer still needs further assays at mRNA and protein levels.