However, FEN1 deficient lung cancer cells were more sensitive to cisplatin treatment, and leading to more accumulation of unrepaired DNA damages in cells.18 Data from breast cancer cell model also verified this conclusion.24 IR combines cisplatin treatment is at present a primary treatment for cancer cells, especially for locally advanced cervical and breast cancers; however, patients often develop resistance to the drug during subsequent treatment. The gene discussed is FEN1; the disease is breast carcinoma.