Yonsei Cancer Hospital identifies RAD51D mutation as breast cancer treatment predictor

Researchers at Yonsei Cancer Hospital have identified that the RAD51D gene mutation can serve as a key indicator for predicting response to chemotherapy in breast cancer patients. The study, published in the journal ‘Molecular Therapy – Oncology’, analyzed clinical data from patients registered between 2016 and 2019.

Findings revealed that patients with the RAD51D mutation (Group A) exhibited more aggressive cancer characteristics, including a higher prevalence of triple-negative breast cancer (50% compared to 20.5% in the non-mutation group) and higher Ki67 expression levels. However, Group A also showed a significantly higher response to neoadjuvant chemotherapy. The rate of pathological complete response—where no cancer cells are observed in surgical tissue—was 66.7% for the mutation group, more than double the 30.5% observed in the non-mutation group.

Cellular experiments confirmed that breast cancer cells with impaired RAD51D function are more sensitive to DNA-damaging agents like cisplatin. This suggests that while RAD51D mutations indicate more aggressive tumors, the resulting deficiency in DNA repair makes these cells more vulnerable to specific treatments. This discovery provides a basis for expanding personalized genetic treatment strategies beyond BRCA1 and BRCA2 mutations to include RAD51D.