Research Paper Volume 13, Issue 13 pp 17407—17427

Figure 1. Characterization of human cisplatin-resistant (CR) ovarian cancer cell lines. (A) Crystal violet cell viability assay. Subconfluent two CR lines OVCAR8CR (a) and SKOV3CR (b), and the respective parental counterparts OVCAR8 (a) and SKOV3 (b) were treated with the indicated concentrations of cisplatin. At 72 h post treatment, cells were fixed and subjected to crystal violet staining. Representative results are shown. The stained cells were dissolved and measured quantitatively for optical absorbance. ^**p < 0.01, compared with that of the parental cells treated with 0 μM cisplatin (or DFM solvent control) group. (B) Cell apoptosis assay. Subconfluent OVCAR8 (a), OVCAR8CR (b), SKOV3CR (c) and SKOV3CR (d) were treated with 0 or 5 μM cisplatin. At 72 h post treatment, cells were collected, fixed and stained with Hoechst33258 and examined under a fluorescence microscope. Representative images are shown. Representative apoptotic cells are indicated by arrows. (C) Expression of the chemoresistance-associated genes in the two cisplatin-resistant human ovarian cancer lines. Subconfluent two CR lines OVCAR8CR (a) and SKOV3CR (b), and the respective parental counterparts OVCAR8 (a) and SKOV3 (b) were treated with 0 or 2 μM cisplatin. At 48 h after treatment, total RNA was isolated and subjected to qPCR analysis of the indicated genes. GAPDH was used as a reference gene. All assays were done in triplicate. ^*p < 0.05, ^**p < 0.01, compared with that of the parental cells treated with 0 μM cisplatin (i.e., DFM solvent control) group.