MRP1/ABCC1基因3＇UTR单核苷酸多态性介导miRNA对原发性肝癌多药耐药性的影响

The multidrug resistance (MDR) is one important reason of the failure for clinical treatment to the primary Hepatocellular Carcinoma (HCC). The study confirmed that MRP1/ABCC1 overexpression can lead to MDR, MRP1/ABCC1 gene SNP which is closely related to individual sensitivity to drugs, but MRP1/ABCC1 gene SNP in HCC can influence miRNA on regulating drug sensitivity of tumor cells or not remaining unclear. This project is combined with bioinformatics technology and experimental biology methods to systematically identify ABCC1 gene SNP which is closely related to drug-resistant hepatocellular carcinoma in primary hepatocellular carcinoma, and analysis the correlated miRNA that influenced on hepatocellular carcinoma drug sensitivity through regulating MRP1/ABCC1 gene SNP. This project will further clarify the function of MRP1/ABCC1 gene SNP of hepatocellular carcinoma, and reveal miRNA regulation drug-resistant mechanism of hepatocellular carcinoma, and provide the new ideas for individual therapy of hepatocellular carcinoma.

多药耐药（MDR）是原发性肝癌（HCC)临床治疗失败的重要原因之一。研究证实，MRP1/ABCC1基因过度表达可导致MDR，且MRP1/ABCC1基因SNP与个体对药物的敏感性有密切的关系，但HCC中MRP1/ABCC1基因SNP能否影响miRNA对肿瘤细胞药物敏感性的调控目前仍不清楚。本项目拟结合生物信息学技术和实验生物学方法，较系统地识别原发性肝癌中与肝癌耐药性密切相关的MRP1/ABCC1基因的SNP，分析相关miRNA调控MRP1/ABCC1基因SNP对肝癌细胞药物敏感性的影响。本项目将进一步阐明HCC中MRP1/ABCC1基因SNP作用及miRNA调控肝癌细胞耐药的机理，为肝癌的个体化治疗提供新思路。

本项目观察了miR-133a、miR-326对人类肝癌细胞HepG2药物敏感性的影响和作用机制；研究了靶向ABCC1基因的miR-133a、miR-326和靶向Bcl-XL基因的miR-133a、miR-326对肝癌HepG2细胞增殖和药物敏感性的影响；探讨了let‑7b与Bcl-XL 3'UTR结合位点SNP对肝癌BEL‑7402细胞Bcl-XL基因表达的作用及对细胞增殖和药物敏感性的影响。研究发现miR-133a、miR-326分别下调了HepG2细胞Bcl-XL以及ABCC1基因的表达。miR-133a、miR-326能够抑制HepG2细胞增殖，增强细胞对化疗药物的敏感性；miR-133a、miR-326分别下调目的基因Bcl-XL和ABCC1能增强人类肝癌细胞HepG2对5-FU、ADM和DDP的敏感性；let‑7b能够靶向抑制Bcl-XL基因的表达增强BEL‑7402细胞对5-FU药物敏感性，Bcl-XL 3'UTR结合位点SNP则会降低BEL‑7402细胞对5-FU药物敏感性。HepG2细胞对5-FU、ADM和DDP的敏感性增强与Bcl-XL、ABCC1的表达下调有关，BEL‑7402细胞对5-FU的敏感性增强与Bcl-XL表达下调有关。这一研究提示，miRNAs（miR-133a、miR-326和let-7b）很可能是抗肿瘤治疗的有效靶点，尤其在抗肿瘤治疗及肿瘤耐药方面发挥重要作用，并能够增强肝癌细胞对化疗药物的敏感性，促进肝癌细胞凋亡，为揭示肝癌细胞耐药的机理及临床制订个体化治疗方案奠定实验基础。