Blocking the FEN1 enzyme to target cancers with DNA repair defects

FEN1 Endonuclease as a Synthetic Lethal Target for Cancer Therapy

NIH-funded research University of California, San Diego · NIH-11137105

Researchers are developing treatments that block the FEN1 enzyme to kill cancers with DNA repair defects, such as BRCA1/2-linked breast and ovarian cancers.

Quick facts

Grant typeR01 grant
Study typeNIH-funded research
Funding institutionUniversity of California, San Diego NIH-funded
Lab location1 site (La Jolla, United States)
Project IDNIH-11137105 on NIH RePORTER

What this research studies

This project uses genetic data and lab models to test whether inhibiting the FEN1 enzyme can selectively kill cancer cells that have problems repairing DNA, like those with BRCA1 or BRCA2 mutations. The team is translating findings from yeast genetics to human cancer genes, running experiments in human cancer cell lines and preclinical models, and searching for drug-like molecules that hit FEN1. They will also look for biomarkers that predict which tumors are most likely to respond so future treatments can be targeted. All work is being done in laboratory and preclinical settings at the University of California San Diego and collaborating labs.

Who could benefit from this research

Good fit: Patients with cancers that carry BRCA1/BRCA2 mutations or other homologous recombination repair defects would be the most likely candidates for therapies developed from this work.

Not a fit: Patients whose tumors have intact DNA repair pathways or cancers driven by unrelated mechanisms may not benefit from FEN1-targeted treatments.

Why it matters

Potential benefit: If successful, this could lead to new targeted drugs that specifically kill tumors with DNA repair defects while reducing harm to normal cells.

How similar studies have performed: The PARP inhibitor approach has already used synthetic lethality successfully in BRCA-mutant cancers, but directly targeting FEN1 is a newer strategy that remains mainly at the laboratory and preclinical stage.

Where this research is happening

La Jolla, 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.
Conditions Anti-Cancer Agents
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.