RAD52 Discovery Brings New Light to Cancer Research

A breakthrough study led by researchers at the University of Iowa has revealed a previously unknown structure of the DNA repair protein RAD52, offering promising insights for developing new cancer therapies. The discovery uncovers how RAD52 forms a protective double-ring structure to stabilise damaged DNA during replication, potentially making it an ideal drug target for cancers deficient in DNA repair mechanisms.

RAD52 and DNA Repair Deficiencies

Cancers such as breast, ovarian, and some brain tumours often carry mutations in key DNA repair genes like BRCA1 and BRCA2. These mutations force cancer cells to rely on alternate repair pathways for survival. RAD52 is one of the proteins that compensates for this deficiency, helping cancer cells replicate even with damaged DNA. Scientists believe that blocking RAD52 could selectively kill such cancer cells while sparing healthy ones.

Discovery of a Unique Double-Ring Formation

Using cryogenic electron microscopy (CryoEM), the research team found that RAD52 assembles into a spool-like structure composed of two protein rings, each containing 11 subunits. These rings bind all three arms of the DNA replication fork — the region where DNA splits for copying — and prevent unwanted interference by motor proteins. This unexpected configuration, never observed before, sheds light on how RAD52 protects DNA during stress and offers new structural targets for drug development.

Potential for New Drug Design

Unlike normal cells, which can function without RAD52, cancer cells with defective DNA repair genes depend on it for survival. This makes RAD52 inhibition a highly selective approach with minimal side effects. The researchers already possess small molecules capable of binding to RAD52, and the new findings will help refine these compounds to create effective and precise anti-cancer drugs. Similar to the PARP inhibitors used against BRCA-deficient cancers, RAD52 blockers could expand treatment options, particularly for tumours resistant to current therapies.

Exam Oriented Facts

• RAD52 is vital for DNA repair in cancers with BRCA1/2 mutations.
• The University of Iowa study revealed a double-ring RAD52 structure via CryoEM.
• The research was led by Professor Maria Spies and published in “Nature” on April 2, 2025.
• Funding was provided by the U.S. National Cancer Institute (NIH grants R01 CA232425 and P30 CA086862).

Collaborative Research and Future Directions

The study was conducted in collaboration with Pietro Pichierri from Italy’s Istituto Superiore di Sanità and Ashley Spies from the University of Iowa College of Pharmacy. Their combined efforts integrated biochemical analysis, single-molecule imaging, and computational modelling to decode the protein’s structure and behaviour. By pinpointing how RAD52’s dual-ring complex guards replication forks, the research opens the door to novel therapeutic strategies aimed at disabling this mechanism — a crucial step toward future cancer treatments that are both targeted and less toxic.