HIF1A and breast cancer: It has been shown that physical exercise and hormone therapy in BC orthotropic mouse model resulted in decreased tumor growth and angiogenesis through downregulation of miR-21, HIF-1α, ERα, VEGF and upregulation of miR-206, let-7a, programmed cell death protein 4 (PDCD-4), IL-10 [151] hence, miR-21 reduction is linked to anti-angiogenic response in BC.