Fig. 6

Further validation of the RB-dependent synergistic effect of PD on CDDP- induced cytotoxicity in MDA-MB-468 cells. a RB mRNA and protein expression levels were significantly higher in RB-overexpressing MDA-MB-468 (OE) cells than in MDA-MB-468 cells transfected with empty plasmid (vector), according to results of RT-PCR and Western blot analysis. b Cell cycle analysis of OE and vector cells treated with PD for 24 h. c Flow cytometry showed that PD enhanced the CDDP-induced apoptosis of OE cells but not vector cells in the PD-CDDP group, and the average percentage of cells in apoptosis was quantified. d A CCK8 assay, colony formation assay and immunofluorescence analysis were performed to determine the cell viability, colony formation and DNA damage, respectively, in OE and vector cells