TY - JOUR
T1 - BCAT1 restricts alpha KG levels in AML stem cells leading to IDHmut-like DNA hypermethylation
AU - Raffel, Simon
AU - Falcone, Mattia
AU - Kneisel, Niclas
AU - Hansson, Jenny
AU - Wang, Wei
AU - Lutz, Christoph
AU - Bullinger, Lars
AU - Poschet, Gernot
AU - Nonnenmacher, Yannic
AU - Barnert, Andrea
AU - Bahr, Carsten
AU - Zeisberger, Petra
AU - Przybylla, Adriana
AU - Sohn, Markus
AU - Toenjes, Martje
AU - Erez, Ayelet
AU - Adler, Lital
AU - Jensen, Patrizia
AU - Scholl, Claudia
AU - Froehling, Stefan
AU - Cocciardi, Sibylle
AU - Wuchter, Patrick
AU - Thiede, Christian
AU - Floercken, Anne
AU - Westermann, Jorg
AU - Ehninger, Gerhard
AU - Lichter, Peter
AU - Hiller, Karsten
AU - Hell, Rudiger
AU - Herrmann, Carl
AU - Ho, Anthony D.
AU - Krijgsveld, Jeroen
AU - Radlwimmer, Bernhard
AU - Trumpp, Andreas
N1 - We thank all members of HI-STEM for discussions, M. Milsom and S. Haas for reading the manuscript, A. Ehninger for help with AML sample acquisition, the members of the Central Animal Laboratory at DKFZ for animal husbandry, the members of the DKFZ Flow Cytometry Core Facility for expertise and support, R. Delwel, P. Valk and B. Lowenberg for providing patient survival data for the Erasmus GSE14468 dataset, and A. Lenze for processing cord blood samples. We thank the EMBL Proteomics Core Facility for assistance with mass spectrometry analysis, the microarray unit of the DKFZ Genomics and Proteomics Core Facility for support, and the Metabolomics Core Technology Platform of the Excellence Cluster CellNetworks for support with ultra-performance liquid chromatography-based metabolite quantification. This work was supported by the SFB873 funded by the Deutsche Forschungsgemeinschaft (DFG) (C.L., C.S., and A.T.), the SyTASC consortium funded by the Deutsche Krebshilfe (A.T.) and the Dietmar Hopp Foundation (A.T.), by grant ZUK 49/2 from the DFG (G.P.), and the DFG Heisenberg-Professorship BU 1339/8-1 (L.B.). Contributions - S.R. designed the study and performed experiments; M.F. performed experiments and bioinformatic analyses with conceptual input from S.R. and C.H.; N.K. performed tracing experiments with the help of Y.N. and K.H.; J.H. and J.K. generated and analysed the proteome data; W.W. helped with cloning, generated growth curves and colony-forming unit assays on HL-60 KD cells, and performed western blotting on primary samples; C.L. and A.D.H. provided AML samples, clinical data, and conceptual input; L.B. provided the GSE16432 dataset and conceptual input; G.P. and R.H. performed targeted metabolomics; A.B., C.B., P.Z., A.P., and M.S. helped with mouse and in vitro experiments; M.T., A.E., L.A., P.J., C.S., and S.F. gave conceptual input; S.C. and L.B. performed RNA-sequencing of paired diagnosis/relapse samples; C.T., A.F., J.W., and G.E. provided AML samples, P.L. financial support, and P.W. healthy HSPC samples; A.T. designed with S.R. the overall study and supervised it. B.R. helped to design and supervise parts of the study; S.R., M.F., N.K., B.R., and A.T. interpreted the results; and S.R. wrote the manuscript with M.F., N.K., B.R., and A.T.
PY - 2017/11/16
Y1 - 2017/11/16
N2 - The branched-chain amino acid (BCAA) pathway and high levels of BCAA transaminase 1 (BCAT1) have recently been associated with aggressiveness in several cancer entities(1-6). However, the mechanistic role of BCAT1 in this process remains largely uncertain. Here, by performing high-resolution proteomic analysis of human acute myeloid leukaemia (AML) stem-cell and non-stem-cell populations, we find the BCAA pathway enriched and BCAT1 protein and transcripts overexpressed in leukaemia stem cells. We show that BCAT1, which transfers a-amino groups from BCAAs to alpha-ketoglutarate (alpha KG), is a critical regulator of intracellular aKG homeostasis. Further to its role in the tricarboxylic acid cycle, alpha KG is an essential cofactor for alpha KG-dependent dioxygenases such as Egl-9 family hypoxia inducible factor 1 (EGLN1) and the ten-eleven translocation (TET) family of DNA demethylases(7-10). Knockdown of BCAT1 in leukaemia cells caused accumulation of aKG, leading to EGLN1-mediated HIF1 alpha protein degradation. This resulted in a growth and survival defect and abrogated leukaemia-initiating potential. By contrast, overexpression of BCAT1 in leukaemia cells decreased intracellular alpha KG levels and caused DNA hypermethylation through altered TET activity. AML with high levels of BCAT1 (BCAT1(high)) displayed a DNA hypermethylation phenotype similar to cases carrying a mutant isocitrate dehydrogenase (IDHmut), in which TET2 is inhibited by the oncometabolite 2-hydroxyglutarate(11,12). High levels of BCAT1 strongly correlate with shorter overall survival in IDH(WT)TET2(WT), but not IDHmut or TET2(mut) AML. Gene sets characteristic for IDHmut AML(13) were enriched in samples from patients with an IDH(WT)TET2(WT)BCAT1(high) status. BCAT1(high) AML showed robust enrichment for leukaemia stem-cell signatures(14,15), and paired sample analysis showed a significant increase in BCAT1 levels upon disease relapse. In summary, by limiting intracellular alpha KG, BCAT1 links BCAA catabolism to HIF1 alpha stability and regulation of the epigenomic landscape, mimicking the effects of IDH mutations. Our results suggest the BCAA-BCAT1-alpha KG pathway as a therapeutic target to compromise leukaemia stem-cell function in patients with IDH(WT)TET2(WT) AML.
AB - The branched-chain amino acid (BCAA) pathway and high levels of BCAA transaminase 1 (BCAT1) have recently been associated with aggressiveness in several cancer entities(1-6). However, the mechanistic role of BCAT1 in this process remains largely uncertain. Here, by performing high-resolution proteomic analysis of human acute myeloid leukaemia (AML) stem-cell and non-stem-cell populations, we find the BCAA pathway enriched and BCAT1 protein and transcripts overexpressed in leukaemia stem cells. We show that BCAT1, which transfers a-amino groups from BCAAs to alpha-ketoglutarate (alpha KG), is a critical regulator of intracellular aKG homeostasis. Further to its role in the tricarboxylic acid cycle, alpha KG is an essential cofactor for alpha KG-dependent dioxygenases such as Egl-9 family hypoxia inducible factor 1 (EGLN1) and the ten-eleven translocation (TET) family of DNA demethylases(7-10). Knockdown of BCAT1 in leukaemia cells caused accumulation of aKG, leading to EGLN1-mediated HIF1 alpha protein degradation. This resulted in a growth and survival defect and abrogated leukaemia-initiating potential. By contrast, overexpression of BCAT1 in leukaemia cells decreased intracellular alpha KG levels and caused DNA hypermethylation through altered TET activity. AML with high levels of BCAT1 (BCAT1(high)) displayed a DNA hypermethylation phenotype similar to cases carrying a mutant isocitrate dehydrogenase (IDHmut), in which TET2 is inhibited by the oncometabolite 2-hydroxyglutarate(11,12). High levels of BCAT1 strongly correlate with shorter overall survival in IDH(WT)TET2(WT), but not IDHmut or TET2(mut) AML. Gene sets characteristic for IDHmut AML(13) were enriched in samples from patients with an IDH(WT)TET2(WT)BCAT1(high) status. BCAT1(high) AML showed robust enrichment for leukaemia stem-cell signatures(14,15), and paired sample analysis showed a significant increase in BCAT1 levels upon disease relapse. In summary, by limiting intracellular alpha KG, BCAT1 links BCAA catabolism to HIF1 alpha stability and regulation of the epigenomic landscape, mimicking the effects of IDH mutations. Our results suggest the BCAA-BCAT1-alpha KG pathway as a therapeutic target to compromise leukaemia stem-cell function in patients with IDH(WT)TET2(WT) AML.
UR - http://www.scopus.com/inward/record.url?scp=85034609644&partnerID=8YFLogxK
U2 - 10.1038/nature24294
DO - 10.1038/nature24294
M3 - مقالة
SN - 0028-0836
VL - 551
SP - 384
EP - 388
JO - Nature
JF - Nature
IS - 7680
ER -