IDH1

Description

IDH1 mutations have been observed in a number of cancer types, including sarcomas, hematologic malignancies, colon cancer and brain cancer. Mutations in the two isocitrate dehydrogenase enzymes involved in cytoplasmic (IDH1) and mitochondrial (IDH2) conversion of alpha-ketoglutarate to D-2-hydroxyglutarate have been described as mutually exclusive in many of these cancer types. The most frequent mutations involve R132 (IDH1) and R172 (IDH2) involve the active site and result in neomorphic enzyme activity. The implications of mutations in this gene vary greatly by cancer type. In myelodysplastic syndromes and acute myeloid leukemia (AML), IDH1 mutations have been associated with worse outcome, shorter overall survival, and normal karyotype. However, in glioblastoma and astrocytoma, patients with IDH1 mutations have shown better overall survival than patients with wild-type IDH1. Unlike the association with cytogenetically normal AML, in glioblastoma, IDH1 mutations have been associated with specific cytogenetic abnormalities, 1p and 19q deletions.