Screening Highly Efficient Sequences Of Small Interfering RNAs Targeting MDR1Gene In Human Hepatocellular Carcinoma Bel-7402/ADM Cells

Objective Screening highly efficient siRNA targeting MDR1gene in multidrugresistant human hepatocellular carcinoma cell subline Bel-7402/ADM cells will be usedto provide new molecular targets for the reversal of multidrug resistance inhepatocellular carcinoma.Methods Four siRNAs(mdrlsi-1、 mdrlsi-2、 mdrlsi-3and mdrlsi-4)specificallytargeting MDR1gene were designed and synthesized with chemical technique. ThesiRNA duplexes were used to transfect into the human hepatocellular carcinomaBel-7402/ADM cells, mediated by Lipofectamine2000. The silencing efficacy of thefour siRNAs was evaluated with RT-PCR for MDR1mRNA expression, western blotfor P-glycoprotein expression,flow cytometry for adriamycin(ADM) accumulation andMMT for sensitivity to ADM.Results The Bel-7402/ADM cells treated with4siRNAs led to reversal effect onmultidrug resistance to different extents. Among the Bel-7402/ADM cells treated bysiRNAs for48h，the depression of MDR1mRNA expression in mdrlsi-1or mdrlsi-3group cells was larger than that of mdrlsi-4or mdrlsi-2group cells (P<0.05).Inaccordance with the order of P-gp expression the mdrlsi-1group cells was the lowest,the mdrlsi-3and the mdrlsi-4were next， and the mdrlsi-2was mostobvious(P<0.05).The Relative reversal efficiency of the mdrlsi-1group cells to ADRwas the highest，The mdrlsi-3was higher (P<0.05).There was no difference in the relative reversal efficiency between mdrlsi-4and mdrlsi-2group cells(P>0.05).Conclusions Compared with the other there siRNAs, mdr1si-1with more reversaleffects on multidrug resistance mediated by MDR1gene were found in the humanhepatocellular carcinoma Bel-7402/ADM cells. Its target site could be a potential targetfor reversal of multidrug resistance in hepatocellular carcinoma.