BMAL1 and breast cancer: Hypoxia significantly reduces BMAL1 protein expression in MCF-7, T47D (luminal A), ZR-75-1 (luminal B), MDA-MB-231, MDA-MB-468, Hs578T (basal-like) human breast cancer, and TUBO and TUBO-P2J (TUBO metastatic variant) mouse breast cancer cells (Figure 1a and Supplementary Table S1).