Article

FOXC1 Is a Potential Prognostic Biomarker with Functional Significance in Basal-like Breast Cancer

Department of Surgical Oncology, John Wayne Cancer Institute, Santa Monica, California 90404, USA.
Cancer Research (Impact Factor: 9.28). 05/2010; 70(10):3870-6. DOI: 10.1158/0008-5472.CAN-09-4120
Source: PubMed

ABSTRACT Gene expression signatures for a basal-like breast cancer (BLBC) subtype have been associated with poor clinical outcomes, but a molecular basis for this disease remains unclear. Here, we report overexpression of the transcription factor FOXC1 as a consistent feature of BLBC compared with other molecular subtypes of breast cancer. Elevated FOXC1 expression predicted poor overall survival in BLBC (P = 0.0001), independently of other clinicopathologic prognostic factors including lymph node status, along with a higher incidence of brain metastasis (P = 0.02) and a shorter brain metastasis-free survival in lymph node-negative patients (P < 0.0001). Ectopic overexpression of FOXC1 in breast cancer cells increased cell proliferation, migration, and invasion, whereas shRNA-mediated FOXC1 knockdown yielded opposite effects. Our findings identify FOXC1 as a theranostic biomarker that is specific for BLBC, offering not only a potential prognostic candidate but also a potential molecular therapeutic target in this breast cancer subtype.

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