ΔNp63α levels correlate with clinical tumor response to cisplatin

After exposure to damaging agents, the p53 tumor suppressor is stabilized mediating cell cycle arrest and apoptosis. p53 family member, Delta Np63 promotes cell proliferation and accelerates tumor growth. We previously found that the genotoxic stress agents induced a decrease of Delta Np63 alpha. We further observed that genotoxic stress mediated phosphorylation of Delta Np63 alpha targeting it into proteasome degradation. Here, we found that high Delta Np63 protein levels in primary tumors accurately predicted response to platinum based chemotherapy and a favorable outcome in head and neck cancer patients. Our data suggest that degradation of Delta Np63 alpha is part of the cellular response to DNA damage in head and neck cancers. The findings may have implications for the rational use of DNA damaging agents in human cancer.