Arsenic and an Old Place: Rescuing p53 Mutants in Cancer

Area of Science:

• Oncology
• Molecular Biology
• Drug Discovery

Background:

• The tumor suppressor p53 protein is crucial for preventing cancer.
• Mutations in p53 are common in many cancers, leading to loss of its tumor-suppressive function.
• Conventional drugs struggle to target p53 due to its lack of typical drug-binding pockets.

Purpose of the Study:

• To identify novel therapeutic strategies for restoring p53 function in cancer.
• To investigate the potential of existing drugs to target p53.
• To discover new roles for established compounds in cancer therapy.

Main Methods:

• Structural analysis of p53.
• Biochemical assays to assess p53 binding and activity.
• Testing the effects of arsenic trioxide on p53 mutants.

Main Results:

• Arsenic trioxide binds to a previously unrecognized, conserved cryptic site on p53.
• This binding event stabilizes the p53 protein.
• Arsenic trioxide reactivates multiple cancer-associated p53 mutants, restoring their tumor-suppressive functions.

Conclusions:

• Arsenic trioxide represents a promising therapeutic agent for cancers with p53 mutations.
• Targeting cryptic sites offers a new avenue for drug development against previously undruggable targets like p53.
• Repurposing existing drugs like arsenic trioxide can accelerate cancer treatment discovery.