Forkhead box A1 expression in breast cancer is associated with luminal subtype and good prognosis

Abstract

Aims: Forkhead box A1 (FOXA1) is a forkhead family transcription factor expressed in breast cancer cells. It is essential for optimal expression of ∼50% of oestrogen receptor (ER)-related genes. This study explored the FOXA1 relationship with luminal and basal breast cancer subtypes, proliferation markers, and survival in breast cancer patients who had received similar treatment. Methods: A tissue microarray comprising tumours from 245 invasive breast cancer patients with 67 months of median follow-up was analysed for FOXA1 expression by immunohistochemistry. Interpretable FOXA1 expression, obtained in 184 patients, was analysed along with other variables such as tumour grade, size, nodal status, ER, progesterone receptor, HER2/neu, proliferation and basal markers. Results: FOXA1 expression (score >3) was seen in 139 of 184 breast cancers. It correlated positively with ERα (pConclusion: Based on this study in patients treated with surgery followed by adjuvant anthracycline-based chemotherapy, FOXA1 expression is associated with good prognosis. It correlates with luminal subtype breast cancer, and could possibly serve as a clinical marker for luminal subtype A. Prognostic ability of FOXA1 in these low-risk breast cancers may prove to be useful in treatment decision making.