Notch stabilizes HIF-1α to promote the Warburg effect. Hypoxia enhances Notch signaling (upregulating DLL4). Notch and HIF-1α cooperatively regulate EMT progression and metabolic reprogramming in breast cancer. Notch1 and HIF-1α show synergistic co-expression in breast cancer. This evidence concerns the gene HIF1A and breast carcinoma.