Fig. 2

YM155 impairs HR. a Cell viability of U251 and U87 pretreated with DMSO or 5 nM YM155 after increased doses of radiation. b Bar graph representation of the number of colonies formed as related to control (DMSO). c Bar graph representation of the percentage of apoptosis as related to control (DMSO). Early apoptosis is measured using annexin V and late apoptosis is measured using PI. d Western blots to assess protein levels of γ-H2AX after treatment of indicated cells with DMSO, YM155, radiation and combined treatment (5 nM YM155 + radiation 4 Gy). e Quantitation of chemiluminescence of western blot analysis in (d). f Western blot analysis for protein levels of Rad51, BRCA1 and γ-H2AX in lysates prepared from cells treated with increasing concentrations of YM155. g HR efficiency of U251 and U87 cells after treatment with DMSO or 5 nM YM155 evaluated using qPCR to detect levels of a recombined fragment. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001