Modulation of RhoA GTPase Activity Sensitizes Human Cervix Carcinoma Cells to γ-Radiation by Attenuating DNA Repair Pathways

Figure 2

Cell death and DNA damage response and repair analyses in HeLa cells expressing RhoA mutants, after γ-radiation treatment. (a) Quantification of senescent cells, by a senescence-associated β-galactosidase assay, performed 96 h after radiation. (b) Quantification of apoptotic cell death after radiation, by Annexin-V and propidium iodide staining (Annexin V⁺/PI⁺ cells were considered apoptotic). (c) Estimation of DNA damage and repair efficiency following radiation, by the olive tail moment (OTM, in arbitrary units) measurements from comet assays. (d) Immunoblotting analysis of phosphorylated Chk1/Chk2 and histone H2AX levels in the different HeLa cell lines, after exposure to 15 Gy of γ-radiation (and using α-Tubulin as loading control). Graphs and immunoblots are representative of three independent experiments. , , and between clones and parental HeLa cells and ^# between treated and untreated conditions (by ANOVA).

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