Since HIF-1α levels are mainly regulated at the level of protein stability [39], and HIF-1α is remarkably down-regulated with the depletion of DEC2, our data suggest that DEC2 may be a facilitator for HIF-1α stabilization in osteosarcomas under the influence of oncogenic signaling or in a hypoxic tumor microenvironment. The gene discussed is BHLHE41; the disease is osteosarcoma.