Radiosensitivity of shGATA3 keratinocytes. (A) Short-term radiosensitivity: Transduced keratinocytes were exposed to 1 cGy or 2 Gy radiation, and viability was measured after 72 h by the XTT method. Results are expressed as the mean percentage +/- SD of viable cells of 3 independent experiments, assuming 100% viability for non-irradiated cells. *p < 0.05. (B) Long-term radiosensitivity: Transduced cells were plated at low density (20 cells/cm2). The next day, they were irradiated at 1 cGy or 2 Gy and then cultured for 2 weeks. The number of colonies obtained is expressed as the mean percentage +/- SD of 3 independent experiments. *p < 0.01.