Fig. 2.

PARPi exposure affects cell viability and induces G2/M cell cycle arrest in RMS cell lines. a Olaparib or AZD2461 treatment for 48 h clearly affected the morphology of both RH30 and RD cells, analysed under light microscope at ×20 magnification. b Viability of RH30 and RD cells treated for 48 h with increasing concentration of Olaparib or AZD2461 expressed in relationship with mocked controls (DMSO), arbitrarily set at 100%, assessed by trypan blue exclusion staining. Each bar represents the mean value of three independent experiments ± SD. Statistical significance: *, p < 0.05, ***, p < 0.005, ns not significant vs. DMSO mocked controls. c Flow cytometry data showing percentages of cells in G1, S and G2 phases in RH30 and RD cells treated for 48 h with Olaparib (1.5 and 5 µM) or AZD2461 (5 and 10 µM). Data are average values of three independent experiments. Statistical significance was < 0.005 in both PARPi-treated RH30 and RD cells vs. mocked controls. d Western blot analyses of a panel of cell cycle regulatory proteins (Cyclin B1, Cyclin D1, p-Cdc2, Cdc25C and p21) in RH30 and RD cells at 48 h after exposure to PARPi. Tubulin expression was used as internal control. Representative blots of three independent experiments