BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, cilt.627, ss.191-199, 2022 (SCI-Expanded)
The D-2-hydroxyglutarate (D-2-HG), whose normal cellular concentration is low, can be accumulated 10-100 times natural levels in some cancer types and participates in the carcinogenesis process. D-2-HG is produced by different pathways specific to cancer type. In this study, the level of significant metabolites produced in some metabolic pathways related to D-2-HG in the energy metabolism was determined in colon adenocarcinoma cell lines at different stages. Then, the differences in TCA and Cori cycle, gluta-minolysis, and Glycolysis were investigated in the brain, colon, liver, and tumor tissues extracted from xenograft models. The levels of glucose, pyruvate, lactate, all TCA cycle intermediates, and D-2-HG were determined by the HPLC analysis, DNS method, and pyruvate assay. The intracellular D-2-HG level was found at 22.6 mmol/mg in primary (Caco-2) and 152.6 mmol/mg in metastatic (SW620) colon adeno-carcinoma cells, whereas it could not be detected in colon epithelial cell line (CCD-18Co). In the xenograft models, D-2-HG could not be detected in CCD-18Co colon and brain tissues, whereas it was produced in Caco-2 and SW620 tissues. Most importantly, the level of D-2-HG was 7.4 and 19.9-fold increased in Caco-2 and SW620 tumor tissues compared to healthy tissue, respectively. In addition, the D-2-HG production pathways were investigated. The results revealed that the carbon source of D-2-HG is glucose, and the imbalance of wt-IDH1/2 enzymes plays a role in its production. Overall, the in vitro and in vivo results show that the enhanced production of endogenous D-2-HG is a characteristic change in the metabolism of colon cancer.(c) 2022 Elsevier Inc. All rights reserved.