Osteosarcoma: K139 has been identified as a novel acetylation site in human p53 accounting for p53-mediated mTOR suppression.180 The p53-4KR mutant retains the ability to inhibit mTOR activity, which is completely abolished in the p53-5KR (K136R + K98R + K117R + K161R + K162R) mutant. Here, MTOR is linked to osteosarcoma.