The TP53 gene is frequently mutated in human tumors.15 The frequency of TP53 mutations in prostate cancer is relatively low, 5–25%, but it is higher in metastatic lesions according to some studies.16, 17, 18 In general, tumors that carry mutant TP53 are more resistant to chemotherapy and radiotherapy, consistent with the notion that DNA-damaging drugs and radiotherapy induce tumor cell death at least in part through the activation of wild-type p53. The gene discussed is TP53; the disease is prostate cancer.