Zoltán Hujber1, Gergő Horváth2, Gábor Petővári1, Titanilla Dankó1, Ildikó Krencz1, Fanni Tóth1, Katalin Mészáros3, Norbert Szoboszlai4, László Tretter2, Attila Patócs3, András Jeney1, Anna Sebestyén1
1 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest
2 Department of Medical Biochemistry, Semmelweis University, Budapest
3 Department of Laboratory Medicine, MTA-SE Lendulet Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest
4 Department of Analytical Chemistry, Institute of Chemistry, Eötvös Loránd University, Budapest
Introduction: Mutation of isocitrate dehydrogenase enzyme (IDH) occur in 80% of low grade gliomas and secondary glioblastomas with a better prognosis compared to non IDH mutant types. These mutations play role in gliomagenesis and cause D-2-hydroxyglutarate (2-HG) oncometabolite production, this contributes to changes in cellular metabolism, epigenetics and reductive oxygen species production. IDH1 mutation status is a critical marker to classify gliomas according to WHO (2016).
Aims: In our study the role of certain metabolic alterations, especially glycolytic activity and mitochondrial functions were examined in glioma cell line models. Further purpose was studying association between IDH1 mutations, altered bioenergetics and signalling pathways.
Method: U87 MG, U373 MG and U251 MG and U251 MG IDH1 R132H transfected cell lines were used in vitro. Cellular respiration, glycolysis, energy substrates oxidation were measured by Seahorse technique. Energy metabolism associated protein expressions, proliferation rates and energy metabolites were also studied. To identify the sources of 2-HG in IDH1 mutant U251 MG cells, cells were fed with 13C-labelled energy substrates.
Results: Glycolysis and oxygen consumption rate of the cell lines showed several differences. The IDH1 mutant U251 cells has lower glycolytic activity and higher respiration than IDH1 wild-type glioma cell line U251 pair. Applying wide range of bioenergetic substrates, it has been found that U251 cells are able to oxidise glutamine, glutamate and malate at significantly higher level than IDH1 mutant U251 cells. The expression pattern of proteins which orchestrate cellular metabolism reflected to the founded bioenergetic differences in the studied glioma cells.
Conclusion: According to our results, IDH1 mutation harbouring glioma cells exhibited a lower glycolysis, a higher cellular respiration and altered glutamine metabolism, which could be potential therapeutic targets in the future.
Doctoral School: Pathology
Supervisor: Anna Sebestyén
E-mail address: firstname.lastname@example.org
Supported by ÚNKP-17-2 and 3, Richter Centenárium Fund, Bolyai Found of Hungarian Academy Sciences and Semmelweis University Innovation Found STIA-KF-17