Preclinical Investigations of PM01183 (Lurbinectedin) as a Single Agent or in Combination with Other Anticancer Agents for Clear Cell Carcinoma of the Ovary
Fig 1
In vitro growth-inhibitory effects of lurbinectedin as a single agent.
A, Sensitivity of CCC and SAC cells to lurbinectedin. CCC (RMG1, RMG2, KOC7C, and HAC2) cells and SAC (A2780, HeyA8, and SKOV-3) cells were treated with the indicated concentrations of lurbinectedin in the presence of 10% FBS for 48 hours. Cell proliferation was assessed using the MTS assay. Data points, mean values; bars, SD (*, significantly different from the control; P <0.05). B, Comparison of the growth-inhibitory activities of 5 anticancer agents. CCC (RMG1 and RMG2) cells were treated with the indicated concentrations of paclitaxel, doxorubicin, SN-38, cisplatin, or lurbinectedin in the presence of 10% FBS for 48 hours. Cell proliferation was assessed using the MTS assay. Data points, mean values; bars, SD (*, significantly different from paclitaxel; P <0.05). C, Lurbinectedin alters the cell cycle distribution of CCC cells. CCC cells (RMG1 and RMG2) were treated with lurbinectedin at a concentration of 1 nmol/L for 48 hours. Then, the cells were detached and fixed with 75% ethanol at -20°C overnight. The cells were subsequently incubated with 100 μg/ml RNase A and 50 μg/ml PI in the dark. A total of 1×104 cells were subjected to flow cytometry. The bar graphs show the percentages of RMG1 and RMG2 cells that had been treated (or not) with lurbinectedin in the subG1, G0/G1, S, and G2/M phases. Data points, mean values; bars, SD. D, Lurbinectedin induces apoptosis in CCC cells. CCC cells (RMG1 and RMG2) were treated with lurbinectedin at concentrations of 0, 0.1, 1, and 10 nmol/L for 48 hours. Then, the cells were detached and subjected to dual staining with both annexin V and FITC, and cellular DNA was stained using PI. A total of 1×104 cells were subjected to flow cytometric analysis. Data points, mean values; bars, SD (*, significantly different from the control; P <0.05). E, Effects of lurbinectedin on the growth of chemoresistant CCC cells. Cisplatin- and paclitaxel-resistant sublines were established as described in the Materials and Methods section. The parental (RMG1 and RMG2), cisplatin-resistant (RMG1-CR and RMG2-CR), and paclitaxel-resistant (RMG1-PR and RMG2-PR) cells were treated with the indicated concentrations of lurbinectedin in the presence of 10% FBS for 48 hours. Cell proliferation was assessed using the MTS assay. Data points, mean values; bars, SD (*, significantly different from the RMG1-CR or RMG1-PR cells; **, significantly different from the RMG2-CR or RMG2-PR cells; P <0.05); CR, cisplatin resistant; PR, paclitaxel resistant. All experiments were repeated at least three times, producing similar results, and representative results are shown.