Indeed, more effective HR in such fractions may provide a high survival, pointing to a significant role of p53-family proteins (in particular, p73 and/or p63) in conferring a stem-like cell and radioresistant phenotype of NSCLC cells that is associated with our previous observation for the ABCG2-overexpressing H1299IR cells. This evidence concerns the gene ABCG2 and non-small cell lung carcinoma.