TP53 and cancer: It regulates cell fate in response to genotoxicity induced by irradiation, cytotoxic drugs, and carcinogens through mediating cell cycle arrest and induction of apoptosis.7 p53 is implicated in a wide array of cellular activities by forming complex signaling networks with various molecular pathway members, such as ER.8 Somatic mutation in the p53 gene occurs frequently in human malignant neoplasms, including breast cancer.