Animals Antibiotics, Antineoplastic Article Cdc25C gene Cdc25C protein Cell Line Cell Line, Tumor Cells, Cultured DNA damage Down-Regulation Doxorubicin G2 Phase Cell Cycle Checkpoints G2 phase cell cycle checkpoint Gene Expression Regulation HCT 116 cell line HCT116 Cells Humans Immunoblotting MDM2 protein, human Mdm2 gene Mice, Knockout Proteolysis Proto-Oncogene Proteins c-mdm2 RNA Interference RNA interference Tumor Suppressor Protein p53 animal animal cell antineoplastic antibiotic cdc25 Phosphatases