R-2HG Exhibits Anti-tumor Activity by Targeting FTO/m6A/MYC/CEBPA Signaling

“To address this question, we conducted integrative analysis of the TCGA AML microarray dataset (Ley et al., 2013) with our RNA-seq data shown in Figure 2A.”

“Knockdown of YTHDF2, a major m6A reader that is responsible for the decay of m6A-modified mRNA transcripts (Wang et al., 2014b) and that is known to bind MYC mRNA (Figure S4N), noticeably increased the stability and expression of MYC transcripts in leukemia cells (Figures 4J and S4O).”

“80% of grade II-III gliomas and secondary glioblastoma (GBM), 10%–20% of acute myeloid leukemia (AML) patients, and at a lower rate in other cancers; most of these lesions involve mutations of arginine (R) residues in codon 132 for IDH1 (IDH1R132) and residues 140 and 172 for IDH2 (IDH2R140 and IDH2R172) (Brat et al.,…”

“Primary AML cells with IDH mutations are also sensitive to JQ1, an inhibitor of MYC signaling (Delmore et al., 2011), often with an IC50 lower than 1 mM, thoughwith a higher IC50 than AML cells with wild-type IDH (Figure 7B; Table S4), likely due to the hyper-activation of MYC signaling in the former.”

“Because IDH mutants block cell differentiation and promote tumor transformation, and inhibition of mutant IDH (IDHi) can reverse this effect, R-2HG (as the major metabolic product of IDH mutants) has been regarded as an oncometabolite (Figueroa et al., 2010; Lu et al., 2012; Rohle et al., 2013;Wang et al., 2013; Xu et…”

“Because IDH mutants block cell differentiation and promote tumor transformation, and inhibition of mutant IDH (IDHi) can reverse this effect, R-2HG (as the major metabolic product of IDH mutants) has been regarded as an oncometabolite (Figueroa et al., 2010; Lu et al., 2012; Rohle et al., 2013;Wang et al., 2013; Xu et…”

“…myeloid leukemia (AML) patients, and at a lower rate in other cancers; most of these lesions involve mutations of arginine (R) residues in codon 132 for IDH1 (IDH1R132) and residues 140 and 172 for IDH2 (IDH2R140 and IDH2R172) (Brat et al., 2015; Mardis et al., 2009; Papaemmanuil et al., 2016).”

“IDH mutants induce a neomorphic enzymatic function that catalyzes the conversion of a-KG to the R enantiomer of 2-hydroxyglutarate (R-2HG) (Dang et al., 2009; Ward et al., 2010).”

“…that leukemia patients with IDH mutations tend to be more sensitive to treatment with hypomethylating agents (AZA and decitabine) (Emadi et al., 2015), ATRA (Boutzen et al., 2016), or standard chemotherapy (daunorubicin and others) (Chou et al., 2011; Patel et al., 2012), than those without.”

“Because IDH mutants block cell differentiation and promote tumor transformation, and inhibition of mutant IDH (IDHi) can reverse this effect, R-2HG (as the major metabolic product of IDH mutants) has been regarded as an oncometabolite (Figueroa et al., 2010; Lu et al., 2012; Rohle et al., 2013;Wang et al., 2013; Xu et…”

“Interestingly, glioma patients with IDH lesions tend to have a better overall survival than those without (Brat et al., 2015; Eckel-Passow et al., 2015), and a similar trend, although still debatable (Marcucci et al.”

“MYC targets and E2F targets are the top gene sets repressed by R-2HG in sensitive cells (see Figure 2), and they are believed to be regulated directly or indirectly by MYC (Lin et al., 2012).”

“R-2HG treatment also significantly increased expression of RARA and ASB2, two direct targets of FTO (Li et al., 2017), in sensitive cells, but not in the resistant cells (Figures S4Q and S4R).”

“…to its effect of increasing global m6A levels in sensitive leukemic cells, R-2HG causes a substantial decrease in global 5hmC abundance in resistant leukemic cells, which most likely attributes to R-2HG-mediated inhibition of TET2, a well-recognized tumor suppressor (Moran-Crusio et al., 2011).”

“Because IDH mutants block cell differentiation and promote tumor transformation, and inhibition of mutant IDH (IDHi) can reverse this effect, R-2HG (as the major metabolic product of IDH mutants) has been regarded as an oncometabolite (Figueroa et al., 2010; Lu et al., 2012; Rohle et al., 2013;Wang et al., 2013; Xu et…”

“R-2HG has also been shown to competitively inhibit the functions of DNA and histone demethylases, such as TET2, JMJD, and KDM, leading to hypermethylated DNA and histones (Chowdhury et al., 2011; Sasaki et al., 2012).”

“Because IDH mutants block cell differentiation and promote tumor transformation, and inhibition of mutant IDH (IDHi) can reverse this effect, R-2HG (as the major metabolic product of IDH mutants) has been regarded as an oncometabolite (Figueroa et al., 2010; Lu et al., 2012; Rohle et al., 2013;Wang et al., 2013; Xu et…”

“, 2015), and a similar trend, although still debatable (Marcucci et al., 2010), was reported in AML patients (Chou et al.”

“The TET2 mutations are thought to occur in the early pre-leukemic stage, which contribute to subsequent cancer initiation (Jan et al., 2012).”

“…leukemia, we exposed 27 human leukemia cell lines (Table S1), none of which carries common IDH1/2 mutations (Table S2), to a series of concentrations of R-2HG; similar or even higher concentrations of R-2HGhave been used in previous studies (Fu et al., 2015; Losman et al., 2013; Lu et al., 2012).”

“R-2HG has also been shown to competitively inhibit the functions of DNA and histone demethylases, such as TET2, JMJD, and KDM, leading to hypermethylated DNA and histones (Chowdhury et al., 2011; Sasaki et al., 2012).”

“Two strategies of R-2HG treatment, including direct R-2HG injection and IDH1R132H-mediated generation of R-2HG, were conducted with immunodeficient NSGS (Wunderlich et al., 2010) and NRGS (Wunderlich et al., 2014) mice.”

“Recent studies further showed that IDH mutations and R-2HG exhibit growth-suppressive activity and glycolysis-inhibitory function 90 Cell 172, 90–105, January 11, 2018 ª 2017 Elsevier Inc. (legend on next page) Cell 172, 90–105, January 11, 2018 91 in gliomas (Bralten et al., 2011; Fu et al., 2015).”

“…that leukemia patients with IDH mutations tend to be more sensitive to treatment with hypomethylating agents (AZA and decitabine) (Emadi et al., 2015), ATRA (Boutzen et al., 2016), or standard chemotherapy (daunorubicin and others) (Chou et al., 2011; Patel et al., 2012), than those without.”

“Recent studies further showed that IDH mutations and R-2HG exhibit growth-suppressive activity and glycolysis-inhibitory function 90 Cell 172, 90–105, January 11, 2018 ª 2017 Elsevier Inc. (legend on next page) Cell 172, 90–105, January 11, 2018 91 in gliomas (Bralten et al., 2011; Fu et al., 2015).”

“R-2HG also causes downregulation of FTO expression indirectly through epigenetic suppression of CEBPA, an essential hematopoiesis-related transcription factor that is required for leukemogenesis (Ohlsson et al., 2014; Ye et al., 2015), via an m(6)A-dependent mechanism in which accumulation of internal m(6)A causes red…”

“…that leukemia patients with IDH mutations tend to be more sensitive to treatment with hypomethylating agents (AZA and decitabine) (Emadi et al., 2015), ATRA (Boutzen et al., 2016), or standard chemotherapy (daunorubicin and others) (Chou et al., 2011; Patel et al., 2012), than those without.”

“…it was reported that leukemia patients with IDH mutations tend to be more sensitive to treatment with hypomethylating agents (AZA and decitabine) (Emadi et al., 2015), ATRA (Boutzen et al., 2016), or standard chemotherapy (daunorubicin and others) (Chou et al., 2011; Patel et al., 2012), than…”

“Based on our previous study on FTO in AML, a recent study suggested that R-2HGmay target FTO (Elkashef et al., 2017).”

“R-2HG treatment led to a substantial decrease of leukemic blasts in PB from both NSGS and NRGS mice with these sensitive cells, but not with the 2HG-resistant AML cells (Figure 1L).”

“R-2HG also causes downregulation of FTO expression indirectly through epigenetic suppression of CEBPA, an essential hematopoiesis-related transcription factor that is required for leukemogenesis (Ohlsson et al., 2014; Ye et al., 2015), via an m(6)A-dependent mechanism in which accumulation of internal m(6)A causes red…”

“Knockdown of YTHDF2, a major m6A reader that is responsible for the decay of m6A-modified mRNA transcripts (Wang et al., 2014b) and that is known to bind MYC mRNA (Figure S4N), noticeably increased the stability and expression of MYC transcripts in leukemia cells (Figures 4J and S4O).”

“In these cells up to ~40% of all mRNA m6A are subjected to demethylation by FTO (Li et al., 2017; Su et al., 2018; Wei et al., 2018).”

“20 In zebrafish, Ythdf2 deletion in embryos decelerates the decay of m6A-modified maternal mRNAs and impedes zygotic genome activation.23 Our recent study revealed that YTHDF2-mediated decay of transcripts of the arterial endothelial genes notch1a and rhoca contributes to the emergence of haematopoietic stem/progenito…”