A comparative study of molecular characteristics of pathogenic and uncertain significance variants of BRCA1/2 in Chinese breast cancer patients.

OBJECTIVE: Although many studies focus on breast cancer patients carrying pathogenic or likely pathogenic variants (P/LPVs) of the breast cancer susceptibility gene (BRCA), the impact of variants of uncertain significance (VUS) on breast cancer remains unclear. This study aims to analyze the tumor biological characteristics of different mutation types of the BRCA in the Shenzhen population. RESULTS: (1) Among the patients included based on the genetic high-risk breast cancer assessment guidelines, the detection rate of BRCA mutations reached 21.2% (87/411) ; (2) Pathogenic variant c.5239 C > T in the BRCA1 was detected in 3 cases, while pathogenic variants c.3109 C > T and c.8951 C > G in the BRCA2 were each detected in 3 cases; (3) In breast cancer patients carrying BRCA and BRCA1 mutations, the negative rates of estrogen receptor and progesterone receptor in the pathogenic or likely pathogenic variants group are higher than those in the variants of uncertain significance group; (4) The types of BRCA mutations (P/LPVs versus VUS) were correlated with the expression levels of estrogen receptor and progesterone receptor.