Project description:Immunosuppressive tumor microenvironments are common in cancers such as metabolic dysfunction-associated steatohepatitis (MASH)-driven hepatocellular carcinoma (HCC). While immune cell metabolism influences effector function, the impact of tumor metabolism on immunogenicity is less understood. ATP citrate lyase (ACLY), a key enzyme linking catabolic and anabolic processes, supports lipid metabolism and gene regulation. Although ACLY inhibition shows anti-proliferative effects in various tumors, clinical translation has been limited by challenges in inhibitor development and compensatory metabolic pathways. Using a mouse model of MASH-driven HCC that mirrors human disease, genetic inhibition of ACLY in hepatocytes and tumors reduced neoplastic lesions by over 70%. To evaluate the therapeutic potential of this pathway, a novel small-molecule ACLY inhibitor, EVT0185 (6-[4-(5-carboxy-5-methyl-hexyl)-phenyl]-2,2-dimethylhexanoic acid), was identified via phenotypic screening. EVT0185 is converted to a CoA thioester in the liver by SLC27A2 with cryo-EM structural analysis revealing EVT0185-CoA directly interacts with ACLY’s CoA binding site. Oral delivery of EVT0185 in four mouse models of MASH-HCC dramatically reduces tumor burden as monotherapy and enhances efficacy of current standards of care including tyrosine kinase inhibitors and immunotherapies. Transcriptomic and spatial profiling in mice and humans linked reduced tumor ACLY with increases in CXCL13, tumor infiltrating B-cells and tertiary lymphoid structures. Remarkably, the depletion of B cells blocked the anti-tumor effects of ACLY depletion. Together, these findings illustrate how targeting tumor metabolism can rewire immune function and suppress cancer progression in MASH-HCC.
Project description:Immunosuppressive tumor microenvironments are common in cancers such as metabolic dysfunction-associated steatohepatitis (MASH)-driven hepatocellular carcinoma (HCC). While immune cell metabolism influences effector function, the impact of tumor metabolism on immunogenicity is less understood. ATP citrate lyase (ACLY), a key enzyme linking catabolic and anabolic processes, supports lipid metabolism and gene regulation. Although ACLY inhibition shows anti-proliferative effects in various tumors, clinical translation has been limited by challenges in inhibitor development and compensatory metabolic pathways. Using a mouse model of MASH-driven HCC that mirrors human disease, genetic inhibition of ACLY in hepatocytes and tumors reduced neoplastic lesions by over 70%. To evaluate the therapeutic potential of this pathway, a novel small-molecule ACLY inhibitor, EVT0185 (6-[4-(5-carboxy-5-methyl-hexyl)-phenyl]-2,2-dimethylhexanoic acid), was identified via phenotypic screening. EVT0185 is converted to a CoA thioester in the liver by SLC27A2 with cryo-EM structural analysis revealing EVT0185-CoA directly interacts with ACLY’s CoA binding site. Oral delivery of EVT0185 in four mouse models of MASH-HCC dramatically reduces tumor burden as monotherapy and enhances efficacy of current standards of care including tyrosine kinase inhibitors and immunotherapies. Transcriptomic and spatial profiling in mice and humans linked reduced tumor ACLY with increases in CXCL13, tumor infiltrating B-cells and tertiary lymphoid structures. Remarkably, the depletion of B cells blocked the anti-tumor effects of ACLY depletion. Together, these findings illustrate how targeting tumor metabolism can rewire immune function and suppress cancer progression in MASH-HCC.
Project description:Immunosuppressive tumor microenvironments are common in cancers such as metabolic dysfunction-associated steatohepatitis (MASH)-driven hepatocellular carcinoma. To further investigate tumor–immune interactions, we performed spatial transcriptomics on livers from MASH-driven HCC mouse models (WD-DEN, WT or Acly KO mice and from WD-CCL4, Vehicle, or EVT0185 (100mg/kg) treated mice). GO enrichment analysis of spatially resolved tumor cells showed increased fatty acid and lipid metabolism in both Acly KO and EVT0185-treated mice Spatial analysis also revealed a selective increase in B cells, but not T cells, macrophages, or NKT cells, in tumors from Acly KO and EVT0185-treated mice.
Project description:The alarming rise in the prevalence of metabolic dysfunction-associated steatohepatitis (MASH) is attributed significantly to dysregulated lipid metabolism. The present study discovered that a novel enedioic acid ACLY inhibitor 326E, an investigational new drug in Phase 2a study for hypercholesterolemia, markedly reduces hepatic lipid accumulation and alleviates MASH in two different mouse models of MASH. Mechanistic studies demonstrated that 326E exerts these effects not only by inhibiting ATP-citrate lyase (ACLY) to reduce de novo lipogenesis but also as a PPARα agonist to increase hepatic fatty acid oxidation with promoted mitochondrial biogenesis. Subsequent studies in cynomolgus monkeys (Macaca fascicularis) confirmed the effectiveness of 326E for MASH in primate species. In a randomized Phase 1b/2a clinical trial in MASH patients 326E was well tolerated and demonstrated a therapeutic potential for MASH signatures. Our results reveal a promising therapeutic potential of 326E for MASH via distinctive dual mechanisms of inhibiting ACLY while activating PPARα.
Project description:The alarming rise in the prevalence of metabolic dysfunction-associated steatohepatitis (MASH) is attributed significantly to dysregulated lipid metabolism. The present study discovered that a novel enedioic acid ACLY inhibitor 326E, an investigational new drug in Phase 2a study for hypercholesterolemia, markedly reduces hepatic lipid accumulation and alleviates MASH in two different mouse models of MASH. Mechanistic studies demonstrated that 326E exerts these effects not only by inhibiting ATP-citrate lyase (ACLY) to reduce de novo lipogenesis but also as a PPARα agonist to increase hepatic fatty acid oxidation with promoted mitochondrial biogenesis. Subsequent studies in cynomolgus monkeys (Macaca fascicularis) confirmed the effectiveness of 326E for MASH in primate species. In a randomized Phase 1b/2a clinical trial in MASH patients 326E was well tolerated and demonstrated a therapeutic potential for MASH signatures. Our results reveal a promising therapeutic potential of 326E for MASH via distinctive dual mechanisms of inhibiting ACLY while activating PPARα.
Project description:Metabolic dysfunction-associated steatohepatitis (MASH)-driven hepatocellular carcinoma (HCC) development is accompanied by the accumulation of immune cells within the hepatic microenvironment, yet its immunological networks remain obscure. Herein, we illustrate the profound reprogramming of the liver immune microenvironment during the transition from MASH to HCC by single-cell RNA sequencing (scRNA-seq).
Project description:We demonstrated that ACBP/DBI inhibition impaired hepatocarcinogenesis in NASH/MASH-driven HCC models. To further investigate its potential mechanisms at transcriptional level in NASH/MASH-driven HCC models, we performed Bulk RNA-seq analyses with liver tissues from the following three models, namely, (i) WD/CCl4 with tamoxifen inducible ACBP/DBI knout mice (Dbi-/- mice, Dbi+/+ mice as control) for in total 27 weeks; (ii) WD/CCl4 with KLH/KLH-ACBP immunized mice for in total 34 weeks; and (iii) HFD/DEN with KLH/KLH-ACBP immunized miceI for a total of 36 weeks.
Project description:De novo lipogenesis is activated in most cancers. Several lipogenic enzymes are implicated in oncogenesis and represent potential cancer therapeutic targets. RNA interference-mediated depletion of ATP citrate lyase (ACLY), the enzyme that catalyzes the first step of de novo lipogenesis, leads to growth suppression in a subset of human cancer cells. Here we demonstrate the molecular basis and potential biomarkers for ACLY-targeting therapy. First, suppression of cancer cell growth by ACLY depletion involves down-regulation of fatty acid elongase ELOVL6 at the transcriptional level. Lipid profiling revealed that ACLY depletion alters fatty acid composition in triglyceride; increased palmitate and decreased longer fatty acids, in accordance with ELOVL6 down-regulation. Second, ACLY depletion increases reactive oxygen species (ROS), whereas addition of antioxidant reduces ROS and attenuates the growth suppression. Third, ACLY depletion or ROS stimulation induce phosphorylation of AMP-activated protein kinase (AMPK), a sensor of energy and lipid metabolism. Analysis of various cancer cell lines revealed that the levels of AMPK phosphorylation (p-AMPK) correlate with the basal ROS levels, and that cancer cells with low basal p-AMPK (i.e., low basal ROS) levels are highly susceptible to ACLY depletion-mediated growth suppression. Finally, in clinical colon cancer tissues, p-AMPK levels are significantly decreased in aggressive tumors and correlate with the levels of 8-hydroxydeoxyguanosine, a hallmark of ROS stimulation. Together, these data suggest that ACLY inhibition suppresses cancer growth via palmitate-mediated lipotoxicity, and p-AMPK could be a predictive biomarker for its therapeutic outcome. Two cell lines are treated with ACLY siRNA. The samples include controls of each cell line.