The Reversal Effect On Multidrug Resistance Gene 1 Mediated Multidrug Resistance In Human Gastric Cancer Cells By Small Interfering RNA

The multidrug resistance (MDR) influences severely the chemotherapy effect and the living quality of patients with carcinoma. There are two categories of MDR: intrinsic MDR and acquired MDR. The multidrug resistance gene 1 (mdrl) with most affirmative function, one kind of human drug-resistance gene family, is recognized firstly, and can encode P-glycoprotein (P-gp) with MW 170 kDa. The P-gp is mainly distributed on the cell membrane and can transport actively anti-tumor drugs. The intracellular drug concentration is reduced by combining anti-tumor drugs with P-gp combining drug sites and pumping the combinator out of the cells, which leads to decreased cytotoxicity.The overall imortality rate of gastric carcinoma in our country presents an increasing trend. Chemotherapy is still one of the most important way in gastric carcinoma treatments. There is the participation of P-gp in intrinsic MDR of the gastric carcinoma. The average P-gp positive rate of human gastric carcinoma is about 54.01% in our country. There is mdrl gene-mediated intrinsic MDR in the human gastric adenocarcinoma cell line BGC823, while in SGC7901 cells, the expression of mdrl is difference according to some reports. The human gastric cancer cell subline SGC7901/VCR with MDR was selected from human gastric cancer SGC7901 cell...