Drugs Targeting p53 Mutations with FDA Approval and in Clinical Trials

Mutations in the tumor suppressor p53 (p53) occur in similar to 50% of human cancers, the majority of which are missense mutations. Mutations in p53 not only impair the tumor suppressive function, but also confer missense mutant p53 (mutp53) with oncogenic activities independent of wild-type p53 (wtp53). Since p53 mutations are cancer-specific, several approaches targeting them have been taken to develop novel cancer therapies, including restoration or stabilization of wtp53 conformation from mutp53, rescue of p53 nonsense mutations, depletion of mutp53 proteins, and induction of p53 synthetic lethality or targeting of vulnerabilities imposed by p53 deficiencies (activated retrotransposons) or mutations (enhanced YAP/TAZ). Here, we summarize clinically available investigational and FDA-approved drugs that target p53 mutations for their mechanisms of action and activities to suppress cancer progression. Mutations in the tumor suppressor p53 (p53) promote cancer progression. This is mainly due to loss of function (LOS) as a tumor suppressor, dominant-negative (DN) activities of missense mutant p53 (mutp53) over wild-type p53 (wtp53), and wtp53-independent oncogenic activities of missense mutp53 by interacting with other tumor suppressors or oncogenes (gain of function: GOF). Since p53 mutations occur in similar to 50% of human cancers and rarely occur in normal tissues, p53 mutations are cancer-specific and ideal therapeutic targets. Approaches to target p53 mutations include (1) restoration or stabilization of wtp53 conformation from missense mutp53, (2) rescue of p53 nonsense mutations, (3) depletion or degradation of mutp53 proteins, and (4) induction of p53 synthetic lethality or targeting of vulnerabilities imposed by p53 mutations (enhanced YAP/TAZ activities) or deletions (hyperactivated retrotransposons). This review article focuses on clinically available FDA-approved drugs and drugs in clinical trials that target p53 mutations and summarizes their mechanisms of action and activities to suppress cancer progression.