Figure 1.
Depletion of DNA-PKcs by specific siRNA sensitizes cells to UV irradiation. A: Immunoblotting analysis shows downregulated expression of DNA-PKcs in HeLa-H1 as compared with the control HeLa-NC cells. The HeLa-H1 and HeLa-NC cells were generated from HeLa cells by stably transfecting with a shRNA vector expressing siRNA specifically targeting DNA-PKcs, and a control siRNA vector expressing a molecule showing no homology with the mammalian genomic DNA. B: Cell growth curves after exposed to 5 J/m2 of Ultraviolet (UV). The data are the means of four independent experiments with standard deviation. * P < 0.05, # P < 0.01 as compared with HeLa-NC cells at the same time point. C: Cell growth curves after exposed to 10 J/m2 of Ultraviolet (UV). The data are the means of four independent experiments with standard deviation. * P < 0.05, # P < 0.01 as compared with HeLa-NC cells at the same time point. D: Cell survival (clonogenic assay) after exposed to different dose of UV radiation. The data are the means of three independent experiments with standard deviation. * P < 0.05 as compared with HeLa-NC cells at the same UV dose.