Although these two genes were not known to be involved in IR response, they are associated with clinical outcomes in cancer: low levels of CCNB1IP1 are associated with poor prognosis in breast and lung cancer (22), and high levels of CTH are correlated with resistance to anti-tumor drugs, such as methotrexate and cisplatin, which affect DNA synthesis or repair (23). Here, CCNB1IP1 is linked to lung carcinoma.