Prof. Andreas von Deimling, University Clinic Heidelberg; Dr Stefan Pusch, German Cancer Research Center; Dr Jörg Balss, German Cancer Research Center
Isocitrate dehydrogenase (IDH) enzymes catalyze the oxidative decarboxylation of isocitrate to alpha ketoglutarate. In humans, three IDH isoforms are known, the homodimers IDH1 and IDH2 and the heterotetramer IDH3.
Mutations in genes encoding IDH enzymes have been identified both in neurometabolic disorders and tumorous diseases. IDH1 have been found in secondary glioblastoma (83 %), diffused astrocytoma (71 %), oligodendrogliomas and oligoastro-cytoma. Mitochondrial IDH2 has been also identified at less frequency (3 %). IDH mutations occur not only in diffuse gliomas, but also in acute myeloid leukemia (IDH1: 6-8.5 %; IDH2: 8.7-11 %), chondrosarcoma (56 %), intrahepatic cholangio-carcinoma (~25 %) and angioimmunoblastic T cell lymphoma (~45 %).
The diagnosis of low-grade gliomas is presently performed by immuno-histological analysis using the IDH1 R132H-specific antibody.
In addition, detection of (D)-2-hydroxyglutarate (D2HG) in tumor tissue, in paraffin-embedded tissues of low-grade gliomas and in blood sera of AML patients can currently only be carried out by individual GC-MS analysis. A robust D2HG test can be done faster than HTS and less expensive.
Researchers from DKFZ and University Hospital of Heidelberg developed a test for detecting (D)-2-hydroxyglutarate in a tumor sample by measuring the production of the reduced state of the dye. The technique can be used for diagnosis but in addition monitoring a (D)-2-hydroxy-glutarate-associated disease of a patient.
Development and distribution of a simple and robust enzymatic assays for the specific determination of the D- (or R-) enantiomer of 2-hydroxyglutarate, i.e. (D)-2-hydroxyglutarate (D2HG). The readout is available already in about 2 to 3 hours. Moreover, they are suitable for 96-well format and can be even further miniaturized to the 384-well format, thereby allowing for the parallel analysis (high-throughput) of numerous samples at the same time. Beside an already granted license for research use only, we now seek a licensee for the DIAGNOSTIC field.
The test can be used for HTS and was successfully tested using on 96-well format.
Priority patent application EP12157663.1 “Means and Methods for the Determination of (D)-2-Hydroxyglutarate (D2HG)” as well as a PCT patent application WO 2013/127997. Granted in Europe as EP2820145 (CH, DE, FR, GB), granted in USA as US9487815, pending in JP, CN.
G1) “Detection of 2-hydroxyglutarate in formalin-fixed paraffin-embedded glioma specimens by gas chromatography/mass spectrometry.” in Brain Pathol. 2012 Jan;22(1):26-31 by Sahm F et al.
2) “Enzymatic assay for quantitative analysis of (D)-2-hydroxyglutarate.” in Acta Neuropathol. 2012 Dec;124(6):883-91 by Balss J et al.
3) “Pan‑mutant IDH1 inhibitor BAY 1436032 for effective treatment of IDH1 mutant astrocytoma in vivo.” In Acta Neuropathol. 2017 Jan 25. PMID: 28124097 by Stefan Pusch et al.
4) “Pan-mutant-IDH1 inhibitor BAY1436032 is highly effective against human IDH1 mutant acute mye-loid leukemia in vivo.” In Leukemia, Jan 2017; doi: 10.1038/leu.2017.46. by A Chaturvedi et al.