CDC25B and breast cancer: CDC25B dephosphorylates and activates CDC2, which is required for entry into mitosis, and is over-expressed in various tumors, including breast cancer (17), colorectal carcinoma (18), endometrioid endometrial carcinoma (19), esophageal squamous cell carcinoma (20), pancreatic ductal adenocarcinoma (21), and non-small cell lung carcinoma (22), among others.