Fig. 3

Cell viability assays 72 h post-radiation. Cells were treated with either radiation only (“control”), or radiation plus erlotinib at 10 μM or 40 μM. Experiments were repeated three times and average of results are shown. Addition of erlotinib resulted in statistically significant decreases in cell viability for Dharma cells at 10 μM, and for all cell lines at 40 μM dose. Enhancement of radiation effects were less pronounced at 10 μM, as seen in Dharma cells. *p <0.05 indicates statistically significant reduction in percentage of viable cells compared to control group at the corresponding radiation dose