Selected drugs that inhibit DNA methylation can preferentially kill p53 deficient cells

Area of Science:

• Molecular Biology
• Genetics
• Cancer Research

Background:

• The p53 protein is a critical regulator of cellular fidelity, preventing mutations under stress.
• Emerging evidence suggests p53 also plays a role in maintaining epigenome stability.
• Deoxycytosine methylation patterns are crucial epigenetic marks in the genome.

Purpose of the Study:

• To investigate the relationship between p53 status and sensitivity to drugs that alter DNA methylation.
• To determine if p53 deficiency or mutation leads to synthetic lethality with DNA methylation inhibitors.

Main Methods:

• Treatment of human and mouse cells with p53 mutations/deficiencies and wild-type controls using DNA methylation-altering drugs.
• In vivo studies using mice with p53 deficiencies or missense mutations.
• Evaluation of human cancer cell xenografts with varying p53 functional status.

Main Results:

• Cells and mice with p53 mutations or deficiencies were preferentially killed by DNA methylation-altering drugs.
• Human cancer xenografts with p53 mutations showed increased sensitivity to these drugs compared to wild-type tumors.
• Loss of p53 function was found to enhance synthetic lethality with drugs targeting deoxycytidine methylation.

Conclusions:

• p53 status significantly influences cellular and organismal response to DNA methylation-modulating therapies.
• The findings reveal a synthetic lethal interaction between p53 loss and drugs affecting DNA methylation patterns.
• This suggests potential therapeutic strategies targeting cancers with p53 alterations.