Furthermore, we found that lactate dehydrogenase A (LDHA) was negatively regulated by BRD7 through promoting proteasomal degradation of HIF1α, and restoring the expression of LDHA in BRD7-overexpressed or breast cancer cells could reverse the effect of BRD7 on aerobic glycolysis, cell proliferation, and apoptosis, as well as the expression of cell cycle and apopotosis related molecules such as cyclin D1, CDK4, P21, and c-poly-ADP-ribose polymerase (c-PARP) both in vitro and in vivo. This evidence concerns the gene HIF1A and breast cancer.