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Updated: Sep 15, 2025
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Quantifying Replication Stress in Ovarian Cancer Cells Using Single-Stranded DNA Immunofluorescence
Published on: February 10, 2023
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Comprehensive RAD51C ovarian cancer variant analysis uncouples homologous recombination and replicative functions
Hayley L Rein1, Yashpal Rawal2, Anna L Palovcak-Lightbourn3
1University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, USA.
Nature Communications
|July 16, 2025
Summary
Researchers identified specific RAD51C gene variants that disrupt its function in DNA repair. This finding helps classify variants of unknown significance and informs ovarian cancer treatment strategies.
Area of Science:
- Genetics
- Molecular Biology
- Oncology
Background:
- RAD51C is a tumor suppressor gene crucial for DNA repair.
- Over 285 variants of unknown significance (VUS) are identified in ovarian tumors.
- RAD51C functions by forming complexes with other RAD51 paralogs.
Purpose of the Study:
- To screen RAD51C variants of unknown significance (VUS) for their impact on functional complex assembly.
- To identify specific RAD51C VUS that affect key DNA repair and replication activities.
- To aid in the pathogenicity classification of RAD51C VUS and inform treatment strategies.
Main Methods:
- Screening of 27 ovarian cancer-derived RAD51C VUS.
- Yeast 3-hybrid assays and biochemical analyses.
- Assessment of homologous recombination (HR), replication fork regression, DNA binding, ATPase activity, and RAD51 filament formation.
Main Results:
- A mutation cluster in the RAD51C Walker B region was identified, affecting interactions with RAD51 paralogs.
- Separation-of-function alleles were found, uncoupling RAD51C's enzymatic activities from HR and replication.
- Functional defects were identified in additional RAD51C VUS.
Conclusions:
- The study identified specific RAD51C VUS with functional defects, improving VUS classification.
- Understanding these defects provides insights into RAD51C's role in DNA repair and replication.
- Findings will aid in developing targeted therapies for ovarian cancer patients with RAD51C loss-of-function alleles.
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