Isocitrate dehydrogenase(IDH)mutations frequently occur in lower-grade gliomas and secondary glioblastomas.Mutant IDHs exhibit a gain-of-function activity,leading to the production of D-2-hydroxyglutarate(D-2HG)by red...Isocitrate dehydrogenase(IDH)mutations frequently occur in lower-grade gliomas and secondary glioblastomas.Mutant IDHs exhibit a gain-of-function activity,leading to the production of D-2-hydroxyglutarate(D-2HG)by reducingα-ketoglutarate(α-KG),a central player in metabolism and epigenetic modifications.However,the role ofα-KG homeostasis in IDH-mutated gliomagenesis remains elusive.In this study,we found that low expression of oxoglutarate dehydrogenase(OGDH)was a common feature in IDH-mutated gliomas,aswellasinastrocytes.ThislowexpressionofOGDHresultedintheaccumulationofα-KGandpromotedastrocytematuration.However,IDH1 mutation significantly reducedα-KG levels and increased glutaminolysis and DNA/histone methylation in astrocytes.These metabolic and epigenetic alterations inhibited astrocyte maturation and led to cortical dysplasia in mice.Moreover,our results also indicated that reduced OGDH expression can promote the differentiation of glioma cells,while IDH1 mutations impeded the differentiation of glioma cells with low OGDH by reducing the accumulation ofα-KG and increasing glutaminolysis.Finally,we found that l-glutamine increasedα-KG levels and augmented the differentiation-promoting effects of AGI5198,an IDH1-mutant inhibitor,in IDH1-mutant glioma cells.Collectively,this study reveals that low OGDH expression is a crucial metabolic characteristic of IDH-mutant gliomas,providing a potential strategy for the treatment of IDH-mutant gliomas by targetingα-KG homeostasis.展开更多
基金supported by funds from the National Key Research and Development Program of China(2022YFA0806501)the National Natural Science Foundation of China(81972342 to J.Y.,82173120 to Y.G.,and 82070298 to L.Z.)the Natural Science Basic Research Plan in ShaanxiProvince(2020JZ-29 to J.Y.).
文摘Isocitrate dehydrogenase(IDH)mutations frequently occur in lower-grade gliomas and secondary glioblastomas.Mutant IDHs exhibit a gain-of-function activity,leading to the production of D-2-hydroxyglutarate(D-2HG)by reducingα-ketoglutarate(α-KG),a central player in metabolism and epigenetic modifications.However,the role ofα-KG homeostasis in IDH-mutated gliomagenesis remains elusive.In this study,we found that low expression of oxoglutarate dehydrogenase(OGDH)was a common feature in IDH-mutated gliomas,aswellasinastrocytes.ThislowexpressionofOGDHresultedintheaccumulationofα-KGandpromotedastrocytematuration.However,IDH1 mutation significantly reducedα-KG levels and increased glutaminolysis and DNA/histone methylation in astrocytes.These metabolic and epigenetic alterations inhibited astrocyte maturation and led to cortical dysplasia in mice.Moreover,our results also indicated that reduced OGDH expression can promote the differentiation of glioma cells,while IDH1 mutations impeded the differentiation of glioma cells with low OGDH by reducing the accumulation ofα-KG and increasing glutaminolysis.Finally,we found that l-glutamine increasedα-KG levels and augmented the differentiation-promoting effects of AGI5198,an IDH1-mutant inhibitor,in IDH1-mutant glioma cells.Collectively,this study reveals that low OGDH expression is a crucial metabolic characteristic of IDH-mutant gliomas,providing a potential strategy for the treatment of IDH-mutant gliomas by targetingα-KG homeostasis.
