IDH-1

Isocitrate dehydrogenase-1 (IDH-1) is a crucial enzyme in the tricarboxylic acid cycle that can catalyze the production of α-ketoglutarate (α-KG) and NADPH. IDH-1 is universally mutated in glioma, and the common site is the substitution of arginine (R) with histidine (H) at position 132. Mutant IDH-1 can convert α-KG to 2-hydroxyglutaric acid (2-HG), which will not only cause epigenetic changing and metabolic reprogramming in cancer cells by up-regulating DNA methylation level, but also promote hypoxia tolerance and tumor angiogenesis by inducing the accumulation of hypoxia tolerant factor-1α. Therefore, IDH-1 has been widely used in the diagnosis of astrocytoma, oligodendroglioma, oligoastrocytoma, secondary glioblastoma and other gliomas, and it is closely related to tumor occurrence. However, patients with mutant IDH-1 often have longer survival time and better prognosis compared to those with the wild-type. One possible reason is that IDH-1 mutation is often accompanied by 1p/19q chromosome deletion, which can increase the chemotherapy sensitivity of the tumor.