HIF1A and central nervous system cancer: EGLN1 knockdown comprised the proliferation of IDH1mt astrocyte while downregulating HIF-1α did the opposite; these results suggest that IDHmt-derived D-2HG activates EGLN1, and subsequent downregulation of HIF-1α may lead to the tumorigenesis of glioma (Koivunen et al., 2012).