[Relationship between survivin expression and chemosensitivity of human lung cancer cells].

OBJECTIVE: To investigate the relationship between survivin expression and the chemosensitivity in multiple drug resistant human lung cancer cell line

METHODS: Human lung cancer cells of the parental cell line H460 and multiple drug resistant cell line H460/cDDP were cultured respectively. RT-PCR and Western blotting were used to detect the mRNA and protein expression of survivin. siRNA targeting survivin was transfected into H460/cDDP cells by Liposomes approach. The expression change of survivin protein after transfection was examined by Western blotting. Cisplatin (DDP) and paclitaxel of different concentrations were added into the culture fluid of the H460/cDDP cells respectively. Methyl thiazolyl tetrazolium (MTT) assay was used to calculate the IC(50) value so as to detect the cytotoxicity of cisplatin and paclitaxel to the cells.

RESULTS: The mRNA expression and protein expression of survivin in the H460/cDDP cells were both significantly higher than those in the H460 cells. 24 h, 48 h, and 72 h after transfection of the survivin siRNA the survivin protein expression levels of the H460/cDDP were decreased by 67.0%, 76.2%, and 92.3% respectively. MTT assay showed that the cisplatin IC(50) levels of the H460/cDDP and H460 cells were 6.3 +/- 0.6 mg/L and 0.8 +/- 0.1 mg/L respectively, and the paclitaxel IC(50) levels were 12.7 +/- 1.2 mg/L and 1.5 +/- 0.3 mg/L respectively. 48 h after the transfection of survivin siRNA, the cisplatin and paclitaxel IC(50) levels of the H460/cDDP cells were decreased to 4.0 +/- 0.9 mg/L (P = 0.002) and 8.1 +/- 1.7 mg/L (P = 0.003) respectively.

CONCLUSION: The survivin expression of the resistant cell line H460/cDDP was up-regulated compared with that of the parental cell line H460. Survivin siRNA sensitized the H460/cDDP cells to both cisplatin and paclitaxel. Survivin participates in the multiple drug resistance mechanism of human lung cancer cells.