Elevated SOX11 expression distinguishes basal-like human breast cancer.
Patients diagnosed with basal-like breast cancer face a more aggressive disease course and more dismal prognosis than patients diagnosed with luminal A and luminal B breast cancer molecular subtypes (1-4). We mined published microarray data (5, 6) to understand in an unbiased fashion the most distinguishing transcriptional features of tumors from patients with basal or basal-like subtype breast cancer. We observed transcriptome-wide differential expression of SRY-box 11, SOX11, when comparing tumors of patients with basal-like breast cancer with that of other PAM50 molecular subtypes. SOX11 mRNA was present at significantly higher quantities in the tumors of patients with basal-like breast cancer. Analysis of patient survival data revealed that SOX11 primary tumor expression was correlated with overall survival, with higher SOX11 associated with inferior outcomes - in basal-like patients but not in luminal A, luminal B, HER2+, or normal-like patients. Elevated SOX11 expression appears to distinguish basal-like human breast cancer from the other molecular subtypes.