[Exploration on the increased sensitivity to docetaxel and reversing mechanism of drug resistance of antisense survivin RNA in gastric cancer cell line SGC7901 cells].

OBJECTIVE: To explore the effects of survivin antisense RNA on apoptosis and chemosensitivity to docetaxel in gastric cancer line SGC7901 cells, and its relation to mdr-1.

METHODS: survivin antisense eukaryotic vector anti-pcDNA3-svv was transfected into SGC7901 cells by electorporation and positive clone was screened out. survivin protein and mdr-1 mRNA were determined by Western blot and RT-PCR. Apoptosis-inducing effect was examined by electron microscopy. Sensitivity to docetaxel was examined by MTT. Expression of mdr-1 and survivin mRNA were detected in the SGC7901 cells after drug-resisitance induction.

RESULTS: The expression of survivin protein of SGC7901 cells after transfection reduced significantly than that of non-transfected cells. MDR indexes of transfection group and non-transfection group were 0.196 +/- 0.013 and 3.126 +/- 0.019, respectively. The IC50 of transfection group to docetaxel was (16.7 +/- 1.98) microg/L and non-transfection group was (55.7 +/- 1. 89) microg/L, with a statistically significant difference. Expression of survivin mRNA in drug-resistant cells decreased along with the decreasing of mdr-1.

CONCLUSION: Antisense surivivin RNA can induce apoptosis in gastric cancer cells and increase sensitivity to docetaxel. The reversing mechanism of drug resistance is related with decreasing of mdr-1.