ERBB2 and breast cancer: To extend the relevance of these findings to human breast cancers, we utilized a breast tissue microarray (TMA) to evaluate Pfkfb3 expression by immunohistochemistry (IHC) across the four major clinical breast cancer subtypes: (i) ER−/PR−/HER2− (TNBC); (ii) ER+/PR+/HER2− (luminal A); (iii) ER+/PR+/HER2+ (luminal B); and (iv) ER−/PR−/HER2+ (HER2+)39.