ARID1A/BAF250a is significantly overexpressed in primary invasive breast cancer

BACKGROUND: ARID1A (also known as BAF250a, p270 or SMARCF1) is a major component of the mammalian SWI/SNF family that is involved in the regulation of the chromatin structure. ARID1A gene mutations have been associated with many types of malignancies, including breast cancer. This study aimed to explore the expression of BAF250a protein in breast cancer and its association with the clinical and pathological characteristics and prognosis of breast cancer. METHODS: We assessed the BAF250a expression in 119 invasive breast carcinomas samples and 92 healthy control and correlated this expression pattern with various clinical and pathologic parameters including histologic type and grade, tumor size, lymph node status, estrogen receptor (ER) status, progesterone receptor (PR) status. Immunohistochemical analysis of BAF250a, ER, PR, was carried out, and evaluation of stainings was performed. RESULTS: The mean value of BAF250a expression in the experimental group was higher than in healthy control (P=0.001). The expression is unrelated to age, menopausal status, lymph node status, tumor size and location, grade and histologic type of tumor, and hormonal status (ER, PR). CONCLUSIONS: These data suggest that BAF250a is overexpressed in breast cancers. BAF250a may play context-dependent tumor-promoting and tumor-suppressive roles in cancer.