Blocking p300 to prevent PARP drug resistance in acidic tumors

Targeting p300 to Overcome PARP inhibitor resistance induced by acidic tumor microenvironment

NIH-funded research University of Tx Md Anderson Can Ctr · NIH-11159411

This project looks at whether blocking a protein called p300 can help PARP drugs work better for people with BRCA-mutant ovarian cancer when tumors become acidic.

Quick facts

Grant typeNIH-funded research
Study typeNIH-funded research
Funding institutionUniversity of Tx Md Anderson Can Ctr NIH-funded
Lab location1 site (Houston, United States)
Project IDNIH-11159411 on NIH RePORTER

What this research studies

Researchers are studying why low pH (acidic) tumor environments make PARP drugs like olaparib less effective in epithelial ovarian cancer, especially in patients with BRCA1/2-related repair defects. In the lab they use cell models, animal studies, and CRISPR genetic screens that identified the epigenetic regulator p300 as a key driver of acidity-induced resistance. The team will test drugs that block p300 together with PARP inhibitors to see if the combination restores cancer cell killing and PARP trapping. They will also analyze tumor samples for biomarkers that could predict who would benefit and help guide future clinical testing.

Who could benefit from this research

Good fit: Ideal candidates are people with epithelial ovarian cancer, particularly those with BRCA1/2 mutations or homologous recombination deficiency who have shown or risk developing resistance to PARP inhibitors.

Not a fit: Patients without ovarian cancer, without BRCA/HDR-related defects, or whose treatment fails for reasons unrelated to tumor acidity or p300 activity are unlikely to benefit from this approach.

Why it matters

Potential benefit: If successful, this approach could restore or extend the effectiveness of PARP inhibitors for patients whose BRCA-related ovarian cancers have become resistant due to an acidic tumor microenvironment.

How similar studies have performed: Combining PARP inhibitors with drugs that target epigenetic regulators has shown promise in preclinical and some early clinical work, but targeting p300 specifically to counteract acidity-driven resistance is a newer, mainly preclinical approach.

Where this research is happening

Houston, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.