Project description:The branched-chain amino acid (BCAA) metabolism plays pleiotropic roles in homeostasis. Here we show that human acute leukemia-initiating cells (LICs), but not normal hematopoietic stem cells, are heavily addicted to the BCAA metabolism, irrespective of myeloid or lymphoid types. Human acute leukemia cells had a high level of BCAAs, transporting free BCAAs into the cytoplasm. Functional inhibition of BCAA transaminase-1 (BCAT1), a catalytic enzyme for BCAAs, induced apoptosis of human LICs, and suppressed reconstitution of human leukemia in xenograft models. Furthermore, deprivation of BCAAs from daily diet in mice transplanted with human LICs strongly inhibited their expansion and self-renewal in vivo. The BCAT1 inhibition inactivates the PRC2 function for epigenetic maintenance of stem cell signatures via downregulation of EZH2 and EED, critical PRC2 components, and inhibited the mTORC1 signaling for leukemia propagation. Thus, targeting the BCAA metabolism should be a powerful approach to erase cancer stemness in human acute leukemias.
Project description:The branched-chain amino acid (BCAA) metabolism plays pleiotropic roles in homeostasis. Here we show that human acute leukemia-initiating cells (LICs), but not normal hematopoietic stem cells, are heavily addicted to the BCAA metabolism, irrespective of myeloid or lymphoid types. To clarify how BCAA metabolism affect the gene expression of human acute leukemia cells, we examined the gene expression alteration in human acute leukemia cell lines in control and BCAA-resrticted culture conditions.
Project description:The branched-chain amino acid (BCAA) metabolism plays pleiotropic roles in homeostasis. Here we show that human acute leukemia-initiating cells (LICs), but not normal hematopoietic stem cells, are heavily addicted to the BCAA metabolism, irrespective of myeloid or lymphoid types. To clarify how BCAA metabolism affect the gene expression of human acute leukemia cells, we examined the gene expression alteration in human acute leukemia cell lines in control and BCAA-resrticted culture conditions.
Project description:The branched-chain amino acid (BCAA) metabolism plays pleiotropic roles in homeostasis. Here we show that human acute leukemia-initiating cells (LICs), but not normal hematopoietic stem cells, are heavily addicted to the BCAA metabolism, irrespective of myeloid or lymphoid types. To clarify how BCAA metabolism affect the gene expression of human acute leukemia cells, we examined the gene expression alteration in human acute leukemia cell lines in control and BCAA-resrticted culture conditions.
Project description:Genome-wide maps of H3K27me3 chromatin modification status regulated by branched chain amino acids (BCAA) metabolism in human acute leukemia
Project description:We used RNA-Seq to ask whether the transcripts for the proposed BCKDH subunits are upregulated in wild-type plants subjected to prolonged darkness. These experiments were performed using rosette leaves from 5-week-old, short-day-grown (8h light/16h dark) Col-0 wild-type plants moved to constant darkness for 6h, 24h, 48h and 72h, and grown in short day for 72h as control. The transcripts of eight BCAA catabolism genes were increased nine- to 400-fold within the first 6h of prolonged darkness, and remained high until the last time point. These results are consistent with the hypothesis that BCAA catabolic enzymes - including BCKDH subunits E1A1, E1B1, E1B2 and E2 - have one or more physiological roles in the dark. Rosette leaf mRNA profiles of 5-week old Col wild type (WT, CS60000) and BCAA catabolic mutants ivd1-2 and hml1-2 were generated byRNA sequencing, in duplicate, using Illumina HiSeq2500.
Project description:Strong associations exist between branched chain amino acids (BCAA) and dysregulated glucose and lipid metabolism, but the underlying mechanisms are not well understood. Here we report that inhibition of the kinase (BDK) or overexpression of the phosphatase (PPM1K) that regulate branched-chain ketoacid dehydrogenase (BCKDH), the committed step of BCAA catabolism, lowers circulating BCAA, reduces hepatic steatosis and improves glucose tolerance in the absence of weight loss in Zucker fatty rats. Phosphoproteomics analysis identified ATP-citrate lyase (ACL) as an alternate substrate of BDK and PPM1K. Overexpression of BDK in liver of lean rats increased ACL phosphorylation and activated de novo lipogenesis. Moreover, BDK and PPM1K transcript levels were increased and repressed, respectively, in response to fructose feeding and expression of the ChREBP transcription factor. These studies identify BDK and PPM1K as a regulatory node that integrates BCAA, glucose, and lipid metabolism via reciprocal regulation of BCKDH and ACL. Modulation of this node relieves key disease phenotypes in a genetic model of severe obesity and metabolic dysfunction.