Fig. 2.

Increase of CDDP and PAC resistance after a 24 h exposure of cholesterol in ovarian cancer cell lines. Ovarian cancer cell lines were pretreated with 5 μg/ml cholesterol for 24 h. (A1) Comparison of IC50 to CDDP and (B2) PAC before and after cholesterol treatment, determined from the data by MTT assay. b Expression of ABCG2 and MDR1 protein 24–48 h after 5 μg/ml cholesterol treatment by Western blot. (C1 and C2) Number of apoptotic cells induced by CDDP and PAC, determined by Annexin V/PI staining. (C3 and C4) Protein expression of cleaved PARP by Western blot and densitometry analysis of cleaved PARP relative to α tubulin. Significant differences are indicated as follows. *P < 0.05, **P < 0.01, ***P < 0.001