Among them, EGLN1 and EGLN3, two α-KG-dependent dioxygenases of the EglN prolyl-4-hydroxylase family (21), were upregulated in IDH mutant LGG patients and served as favorable indicators for LGG prognosis, which is consistent with previous studies proving that 2-HG specifically increased the activity of EglN enzymes in human astrocytes (22) and that overexpression of EGLN3 could suppress tumor progression of glioma models by normalized glioma capillary architecture and tightly associated with hypoxic environment (23, 24). Here, IDH2 is linked to central nervous system cancer.