A combined pharmacological inhibition of both HIF-1α and TGF-β, which targets both cancer cells and bone microenvironment had an additive effect more than either treatments alone indicating that hypoxia and TGF-β signaling drive in parallel tumor bone metastases and that pharmacological inhibitors, by acting on both tumor cells and the bone microenvironment, can additively decrease tumor burden [120]. This evidence concerns the gene TGFB1 and cancer.