Reversal effect of neferine on resistance to vincristine in human multidrug-resistant gastric carcinoma cell line SGC7901/VCR / 中国病理生理杂志

ABSTRACT

AIM: To investigate the effect of neferine (Nef) on human gastric carcinoma cell line with multidrug resistance (MDR). METHODS: The cytotoxic effect of vincristine (VCR) was evaluated by MTT assay. The cell apoptosis induced by VCR was determined by flow cytometry, and the expression of P-glycoprotein (P-gp) and multidrug-resistance-associated protein (MRP) in cells was examined by immunofluorescence flow cytometry. RESULTS: MTT assay showed that Nef at the concentration of 5 ?mol?L~(-1) to 10 ?mol?L~(-1) have no cytotoxicity to parent human gastric carcinoma cell line (SGC7901) and its VCR-resistant variant cell line (SGC7901/VCR). The IC_(50) value of VCR to SGC7901 cell line was 0.06 mg?L~(-1)and that of to SGC7901/VCR cell line was 2.32 mg?L~(-1), which indicated SGC7901/VCR cell line were 39 times more resistant to VCR in comparison with the parent SGC7901 cell line. After treatment with Nef at the concentrations of 2.5, 5 and 10 ?mol?L~(-1), the IC_(50) value of VCR to SGC7901/VCR cell line decreased to 0.34, 0.12 and 0.05 mg?L~(-1), respectively and those increased by 6.8-, 18.1- and 43.8- fold in the chemosensitivity, respectively. Flow cytometry showed that SGC7901/VCR cells were resistant to apoptosis induced by VCR. After 24 h treatment with Nef (2.5, 5 and 10 ?mol?L~(-1)) and VCR, the apoptosis of SGC7901/VCR cells increased, which indicated Nef could abolish resistance of SGC7901/VCR cells to VCR-induced apoptosis. Furthermore, the action of Nef was more potent than verapamil. The expression of P-glycoprotein and multidrug resistance associated protein was strongly positive in SGC7901/VCR cells, and the expression level of P-gp and MRP in SGC701/VCR cells was significantly down-regulated at 24 h after treatment with Nef (10 ?mol?L~(-1)). CONCLUSIONS: Nef can reverse MDR in multidrug-resistant human gastric carcinoma SGC7901/VCR cell line. Its mechanism might be associated with down-regulation of expression of P-gp and MRP in SGC7901/VCR cells.