OTUB1 and breast cancer: FOXM1 has an essential function in enhancing DNA damage repair and genotoxic agent resistance.5, 8, 9, 10 Previous research has also demonstrated that OTUB1 can modulate DNA damage response by promoting protein deubiquitination.17 We show, in here, that OTUB1 can promote deubiquitination and stabilization of FOXM1 in response to the genotoxic agent epirubicin in breast cancer.