Expression of BRCA1 and WWOX and their clinicopathologic implication in breast carcinomas occurring in young women

Abstract

To explore the clinicopathologic characteristics and biological markers of breast carcinomas in young women. Immunohistochemical SP method was used to study breast cancer susceptibility gene (BRCA1) and WWOX in breast carcinomas of patient ≤ 35 years of age (107 cases) and ≥ 60 years of age (112 cases). The findings were correlated with clinicopathological features. In addition, PCR amplification and direct sequencing were performed to detect the BRCA1 gene mutation of exons 2 and 20 using fresh frozen tissue samples in other 10 patients who were ≤ 35 years of age. The positive rate of BRCA1 protein expression was higher in the young age group [65.4% (70/107)] than that of the old age group [35.7% (40/112)]. ER, PR, HER2, and WWOX protein expression and proliferation marker Ki-67 were no statistically different in the two groups (all P > 0.05). BRCA1 expression was significantly correlated with pTNM and axillary lymph node metastasis (both P < 0.05), but not with ER, PR, HER2 and WWOX protein expression (all P > 0.05). Ki-67 and histological grading showed no statistical correlation (P > 0.05). WWOX protein expression showed no correlation with clinicopathologic characteristics (all P > 0.05). Mutation of exons 2 and 20 of the BRCA1 gene was not detected in any of 10 cases studied. BRCA1 cytoplasmic expression statistically correlates with the development and prognosis of breast cancer of young patients.