Mutant forms of EGFR (D746-750, L858R, and the targeted-therapy resistant T790M mutant) confer radiosensitivity to hypoxic lung cancer cells, at least in part due to downregulation of RAD50, a member of the MRE11/RAD50/NBS1 complex that plays early end-processing and signaling roles in NHEJ and HR[190]. Here, RAD50 is linked to lung cancer.