Both growth arrest and apoptosis are triggered upon p53 activation, thus, the inactivation of p53 signaling pathways allows damaged cells to proliferate, leading to the development of tumors.4 More than 50% of human cancer have a mutant p53 gene.5 Delivery of the wild-type p53 (wt-p53) gene to a cancer cell can increase the levels of wt-p53 protein and trigger apoptosis or growth arrest, leading to the inhibition of tumor growth.6 The gene discussed is TP53; the disease is cancer.