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1.
Science ; 385(6705): eadl6173, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38991060

ABSTRACT

Isocitrate dehydrogenase 1 (IDH1) is the most commonly mutated metabolic gene across human cancers. Mutant IDH1 (mIDH1) generates the oncometabolite (R)-2-hydroxyglutarate, disrupting enzymes involved in epigenetics and other processes. A hallmark of IDH1-mutant solid tumors is T cell exclusion, whereas mIDH1 inhibition in preclinical models restores antitumor immunity. Here, we define a cell-autonomous mechanism of mIDH1-driven immune evasion. IDH1-mutant solid tumors show selective hypermethylation and silencing of the cytoplasmic double-stranded DNA (dsDNA) sensor CGAS, compromising innate immune signaling. mIDH1 inhibition restores DNA demethylation, derepressing CGAS and transposable element (TE) subclasses. dsDNA produced by TE-reverse transcriptase (TE-RT) activates cGAS, triggering viral mimicry and stimulating antitumor immunity. In summary, we demonstrate that mIDH1 epigenetically suppresses innate immunity and link endogenous RT activity to the mechanism of action of a US Food and Drug Administration-approved oncology drug.


Subject(s)
Immune Evasion , Immunity, Innate , Isocitrate Dehydrogenase , Neoplasms , Animals , Humans , Mice , Cell Line, Tumor , DNA/metabolism , DNA Demethylation , DNA Methylation , DNA Transposable Elements , Epigenesis, Genetic , Glutarates/metabolism , Immunity, Innate/genetics , Isocitrate Dehydrogenase/genetics , Isocitrate Dehydrogenase/metabolism , Mutation , Neoplasms/immunology , Neoplasms/genetics , Nucleotidyltransferases/genetics , Tumor Escape , Immune Evasion/genetics
2.
Clin Exp Dermatol ; 2024 May 03.
Article in English | MEDLINE | ID: mdl-38699939

ABSTRACT

BACKGROUND: Dysregulated interleukin (IL)-17/IL-23 signaling contributes to psoriasis pathogenesis. Cedirogant is an inverse agonist of retinoic acid-related orphan receptor gamma thymus (RORγt), a key transcription factor responsible for IL-17 synthesis and a regulator of the T helper 17 cell lineage program. OBJECTIVE: To evaluate the efficacy and safety of cedirogant to treat moderate-to-severe psoriasis. METHODS: In this phase 2b, multicenter, double-blind, 16-week study (NCT05044234), adults aged 18-65 years were randomized 1:1:1:1 to once-daily oral cedirogant 75 mg, 150 mg, 375 mg, or placebo. Assessments included ≥50%/75%/90%/100% improvement from baseline in Psoriasis Area and Severity Index (PASI 50/75/90/100), static Physician Global Assessment 0/1, Psoriasis Symptoms Scale 0, and improvements in itch, adverse events (AEs), pharmacokinetics, and IL-17A/F levels. Efficacy results based on observed cases were summarized descriptively. RESULTS: Of 156 enrolled patients, most were male (70.5%); 39 patients were randomized to each treatment. Only 47 patients completed the study; the study was terminated early due to preclinical findings. At week 16, PASI 75 achievement rates (primary endpoint) were 28.6%, 7.7%, and 41.7% in the cedirogant 75 mg, 150 mg, and 375 mg groups, respectively, and 0% in the placebo group. AE rates were similar in the cedirogant 75 mg, 150 mg, and placebo groups and higher in the cedirogant 375-mg group; most AEs were mild or moderate. CONCLUSIONS: Patients with psoriasis who received cedirogant showed PASI improvement and cedirogant was generally well tolerated. Results should be interpreted in the context of early study termination. Cedirogant development has been discontinued.

3.
Nat Cancer ; 4(3): 365-381, 2023 03.
Article in English | MEDLINE | ID: mdl-36914816

ABSTRACT

Adult liver malignancies, including intrahepatic cholangiocarcinoma and hepatocellular carcinoma, are the second leading cause of cancer-related deaths worldwide. Most individuals are treated with either combination chemotherapy or immunotherapy, respectively, without specific biomarkers for selection. Here using high-throughput screens, proteomics and in vitro resistance models, we identify the small molecule YC-1 as selectively active against a defined subset of cell lines derived from both liver cancer types. We demonstrate that selectivity is determined by expression of the liver-resident cytosolic sulfotransferase enzyme SULT1A1, which sulfonates YC-1. Sulfonation stimulates covalent binding of YC-1 to lysine residues in protein targets, enriching for RNA-binding factors. Computational analysis defined a wider group of structurally related SULT1A1-activated small molecules with distinct target profiles, which together constitute an untapped small-molecule class. These studies provide a foundation for preclinical development of these agents and point to the broader potential of exploiting SULT1A1 activity for selective targeting strategies.


Subject(s)
Alkylating Agents , Liver Neoplasms , Humans , Sulfotransferases , Liver Neoplasms/drug therapy , Arylsulfotransferase
4.
Am J Gastroenterol ; 117(12): 2075-2078, 2022 12 01.
Article in English | MEDLINE | ID: mdl-36066458

ABSTRACT

INTRODUCTION: Bile duct involvement is a key finding of primary biliary cholangitis (PBC). The aim of this study was to evaluate baseline ductopenia and disease progression. METHODS: Retrospective longitudinal histological follow-up of treatment-naive patients with PBC. RESULTS: Eighty-three patients were included, with ductopenia correlated to fibrosis stage at baseline. The cumulative incidence of severe ductopenia remained stable after 5 years, whereas fibrosis continually increased over time. Baseline AST-to-Platelet Ratio Index and elevated alkaline phosphatase >2 times the normal with abnormal bilirubin were associated with ductopenia progression. DISCUSSION: Bile duct injury does not seem to follow the same course as fibrosis in PBC.


Subject(s)
Cholangitis , Liver Cirrhosis, Biliary , Humans , Liver Cirrhosis, Biliary/complications , Liver Cirrhosis, Biliary/diagnosis , Liver Cirrhosis, Biliary/epidemiology , Retrospective Studies , Bile Ducts/diagnostic imaging , Bile Ducts/pathology , Fibrosis , Incidence , Cholangitis/diagnosis
5.
Hepatol Commun ; 4(11): 1717-1724, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33163840

ABSTRACT

Liver transplant centers in the United States retain great autonomy in determining eligibility criteria for a liver transplant. This study aims to define the availability and content of liver transplant centers' publicly available Internet policies regarding eligibility criteria for liver transplant. Three trained undergraduate students performed a structured pilot-tested assessment of official websites of the United Network for Organ Sharing-registered liver transplant centers. All 141 liver transplant centers had an accessible website. Some account of eligibility criteria was provided by 53% of centers, while 32% of centers discussed substance use. Only 17% discussed their policy regarding alcohol use in candidates with underlying alcohol use disorder, and only 2% stipulated that 6 months of abstinence was required. While exclusion based on substance use or age was discussed infrequently, insurance coverage requirements, the need for social support, and the need for adherence to medical care were mentioned in 21%, 37%, and 23% of centers, respectively. Conclusion: In 2018, half of liver transplant centers provided some information on their official websites regarding eligibility criteria for liver transplant. Detailed information regarding substance use disorders and social health requirements was rare. The Internet is infrequently used by liver transplant centers as a means to publicly share information regarding selection criteria.

6.
Hepatol Commun ; 2(8): 919-928, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30094403

ABSTRACT

Noncirrhotic portal hypertension (NCPH) is a rare disease that may lead to serious clinical consequences. Currently, noninvasive tools for the assessment of NCPH are absent. We investigated the utility of spleen and liver volumetrics as a marker of the presence and severity of portal hypertension in this population. A cohort of NCPH patients evaluated between 2003 and 2015 was retrospectively studied. The association of spleen and liver volumes with the hepatic venous pressure gradient (HVPG) level was evaluated using locally weighted scatterplot smoothing curves. A cohort of patients with viral hepatitis-related liver disease was used as controls. Of the 86 patients with NCPH evaluated during the study period, 75 (mean age, 35 ± 17; 73% males) were included in the final analysis. Patients with portal hypertension had significantly higher spleen and liver to body mass index (BMI) ratios compared to patients with HVPG <5 mm Hg (39.5 ± 27.9 versus 22.8 ± 10.6 cm3/kg/m2, P = 0.003; 91.1 ± 40.1 versus 71.4 ± 16.7 cm3/kg/m2, P = 0.014, for spleen/BMI and liver/BMI, respectively). In contrast to the patients with viral hepatitis, a positive linear correlation was observed in the NCPH cohort between spleen/BMI and liver/BMI (above a cutoff of 25 and 80 cm3/kg/m2, respectively) and HVPG level. Additionally, only in the NCPH cohort was an increase in spleen/BMI range quartile predictive of a higher prevalence of portal hypertension and clinically significant portal hypertension (trend, P = 0.014 and 0.031, respectively). Conclusion: Spleen and liver volumetrics may have utility in the assessment of NCPH as a noninvasive biomarker that can be performed using routine radiologic examinations. Further studies are needed to validate these findings. (Hepatology Communications 2018; 00:000-000).

7.
Hepatology ; 66(2): 591-601, 2017 08.
Article in English | MEDLINE | ID: mdl-28422310

ABSTRACT

Cystic fibrosis (CF) liver disease (CFLD), a leading cause of death in CF, is mostly described in pediatric populations. Adult-onset CFLD lacks sufficient characterization and diagnostic tools. A cohort of CF patients without CFLD during childhood were followed for up to 38 years with serologic testing, imaging, and noninvasive fibrosis markers. Historical CFLD diagnostic criteria were compared with newly proposed CFLD criteria. Thirty-six CF patients were followed for a median of 24.5 years (interquartile range 15.6-32.9). By the last follow-up, 11 (31%) had died. With conventional criteria, 8 (22%) patients had CFLD; and by the new criteria, 17 (47%) had CFLD at a median age of 36.6 years (interquartile range 26.5-43.2). By the new criteria, those with CFLD had higher median alanine aminotransferase (42 versus 27, P = 0.005), aspartate aminotransferase (AST; 26 versus 21, P = 0.01), direct bilirubin (0.13 versus 0.1, P = 0.01), prothrombin time (14.4 versus 12.4, P = 0.002), and AST-to-platelet ratio index (0.31 versus 0.23, P = 0.003) over the last 2 years of follow-up. Subjects with a FibroScan >6.8 kPa had higher alanine aminotransferase (42 versus 28U/L, P = 0.02), AST (35 versus 25U/L, P = 0.02), AST-to-platelet ratio index (0.77 versus 0.25, P = 0.0004), and Fibrosis-4 index (2.14 versus 0.74, P = 0.0003) and lower platelet counts (205 versus 293, P = 0.02). One CFLD patient had nodular regenerative hyperplasia. Longitudinally, mean platelet counts significantly declined in the CFLD group (from 310 to 230 U/L, P = 0.0005). Deceased CFLD patients had lower platelet counts than those alive with CFLD (143 versus 258 U/L, P = 0.004) or those deceased with no CFLD (143 versus 327U/L, P = 0.006). CONCLUSION: Adult-onset CFLD may be more prevalent than previously described, which suggests a later wave of CFLD that impacts morbidity; routine liver tests, radiologic imaging, noninvasive fibrosis markers, and FibroScan can be used algorithmically to identify adult CFLD; and further evaluation in other CF cohorts should be performed for validation. (Hepatology 2017;66:591-601).


Subject(s)
Cause of Death , Cystic Fibrosis/diagnosis , Cystic Fibrosis/epidemiology , Liver Diseases/diagnosis , Liver Diseases/epidemiology , Adult , Age of Onset , Biopsy, Needle , Child , Child, Preschool , Cohort Studies , Female , Humans , Immunohistochemistry , Liver Function Tests , Male , Prospective Studies , Risk Assessment , Severity of Illness Index , Survival Analysis
9.
Mol Genet Metab ; 107(4): 674-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23137569

ABSTRACT

Single nucleotide polymorphism (SNP) arrays possess clinical potential due to their high throughput capacity, sensitivity and versatility. We used such an array to perform a genome-wide SNP analysis of a patient with a multi-system undiagnosed disease involving peripheral neuropathies and food intolerances. The patient had a homozygous deletion within the gene encoding maltase-glucoamylase (MGAM), an intestinal starch digestion enzyme, predicting absence of enzyme activity and potential starch indigestion. We then performed validation testing using a functional MGAM analysis that involved starch ingestion followed by measuring blood glucose and insulin levels as well as hydrogen breath levels. Gastrointestinal tissue was also obtained via endoscopy and immunohistochemical staining for intestinal MGAM was performed. Our results strongly suggest the presence and functioning of MGAM which disproved deficiency predictions based on SNP array analysis findings, classifying the deletion as a functional polymorphism. This study highlights a current clinical limitation of SNP arrays, i.e., distinguishing deleterious genomic alterations from misleading functional polymorphisms. We conclude that novel findings from SNP arrays should be clinically validated and published.


Subject(s)
Homozygote , Polymorphism, Single Nucleotide , Sequence Deletion , alpha-Glucosidases/genetics , Blood Glucose , Female , Genome-Wide Association Study , Humans , Insulin/blood , Intestinal Mucosa/enzymology , Middle Aged , Oligonucleotide Array Sequence Analysis , alpha-Glucosidases/metabolism
10.
Gastroenterology ; 141(4): 1220-30, 1230.e1-3, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21726511

ABSTRACT

BACKGROUND & AIMS: Chronic infection with hepatitis B or C virus (HBV or HCV) is a leading cause of cirrhosis by unknown mechanisms of pathogenesis. Translocation of gut microbial products into the systemic circulation might increase because of increased intestinal permeability, bacterial overgrowth, or impaired clearance of microbial products by Kupffer cells. We investigated whether the extent and progression of liver disease in patients with chronic HBV or HCV infection are associated with microbial translocation and subsequent activation of monocytes. METHODS: In a retrospective study, we analyzed data from 16 patients with minimal fibrosis, 68 with cirrhosis, and 67 uninfected volunteers. We analyzed plasma levels of soluble CD14 (sCD14), intestinal fatty acid binding protein, and interleukin-6 by enzyme-linked immunosorbent assay, and lipopolysaccharide (LPS) by the limulus amebocyte lysate assay, at presentation and after antiviral treatment. RESULTS: Compared with uninfected individuals, HCV- and HBV-infected individuals had higher plasma levels of LPS, intestinal fatty acid binding protein (indicating enterocyte death), sCD14 (produced upon LPS activation of monocytes), and interleukin-6. Portal hypertension, indicated by low platelet counts, was associated with enterocyte death (P=.045 at presentation, P<.0001 after therapy). Levels of sCD14 correlated with markers of hepatic inflammation (P=.02 for aspartate aminotransferase, P=.002 for ferritin) and fibrosis (P<.0001 for γ-glutamyl transpeptidase, P=.01 for alkaline phosphatase, P<.0001 for α-fetoprotein). Compared to subjects with minimal fibrosis, subjects with severe fibrosis at presentation had higher plasma levels of sCD14 (P=.01) and more hepatic CD14+ cells (P=.0002); each increased risk for disease progression (P=.0009 and P=.005, respectively). CONCLUSIONS: LPS-induced local and systemic inflammation is associated with cirrhosis and predicts progression to end-stage liver disease in patients with HBV or HCV infection.


Subject(s)
Bacterial Translocation , Hepatitis B, Chronic/complications , Hepatitis C, Chronic/complications , Host-Pathogen Interactions , Intestines/virology , Liver Cirrhosis/virology , Monocytes/virology , Biomarkers/blood , Biopsy , Cell Death , Disease Progression , End Stage Liver Disease/microbiology , End Stage Liver Disease/virology , Enterocytes/microbiology , Enterocytes/pathology , Enterocytes/virology , Enzyme-Linked Immunosorbent Assay , Fatty Acid-Binding Proteins/blood , Female , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/immunology , Hepatitis B, Chronic/microbiology , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/immunology , Hepatitis C, Chronic/microbiology , Humans , Hypertension, Portal/microbiology , Hypertension, Portal/virology , Interleukin-6/blood , Intestines/immunology , Intestines/microbiology , Intestines/pathology , Kupffer Cells/microbiology , Kupffer Cells/virology , Limulus Test , Lipopolysaccharide Receptors/blood , Lipopolysaccharides/blood , Liver Cirrhosis/diagnosis , Liver Cirrhosis/immunology , Liver Cirrhosis/microbiology , Logistic Models , Male , Maryland , Middle Aged , Monocytes/immunology , Monocytes/microbiology , Odds Ratio , Retrospective Studies , Severity of Illness Index
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