Lin28 transfection induced radiation resistance via inhibiting H2A.X pathway.Lin28 increased radioresistance by affecting the RAS oncogene and genes associated with DNA damage repair.Lin28 decreased chemosensitivity via inhibiting miRNA-107, let-7, Rb, p21 and Bcl-xL.Lin28 was associated with susceptibility and clinical features in breast cancer, including the response to neo-adjuvant chemotherapy. The gene discussed is BCL2L1; the disease is breast cancer.