Fig. 5

PD synergistically enhanced CDDP-mediated cytotoxicity in a potentially RB-dependent manner. a RB mRNA and protein expression levels in MDA-MB-231 cells were dramatically decreased by shRB, according to the results of RT-PCR and Western blot analysis. b Cell cycle analysis of sh-MDA-MB-231 cells treated with PD for 24 h. c Flow cytometry showed that PD did not enhance the CDDP-induced apoptosis of sh-MDA-MB-231 cells, and the average percentage of cells in apoptosis was quantified. d CCK8 assay, colony formation assay and immunofluorescence analysis were performed and showed that PD did not significantly enhance the CDDP-induced inhibition of cell viability or colony formation or increase in DNA damage in sh-MDA-MB-231 cells. e The IC50 of CDDP was calculated in sh-MDA-MB-231 cells treated with PD-CDDP