Background and Aims: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. Nonalcoholic steatohepatitis (NASH), the progressive form of NAFLD, and advanced fibrosis are associated with poor outcomes. We searched for their noninvasive biomarkers.Approach and Results: Global RNA sequencing of liver tissue from 98 patients with biopsy-proven NAFLD was performed. Unsupervised hierarchical clustering well distinguished NASH from nonalcoholic fatty liver (NAFL), and NASH patients exhibited molecular abnormalities reflecting their pathological features. Transcriptomic analysis identified proteins upregulated in NASH and/or advanced fibrosis (stage F3-4), including matricellular glycoprotein thrombospondin-2 (TSP-2), encoded by the thrombospondin 2 (THBS2) gene. The intrahepatic THBS2 expression level showed the highest areas under the receiver operating characteristic curves (AUROCs) of 0.915 and 0.957 for diagnosing NASH and advanced fibrosis, respectively. THBS2 positively correlated with inflammation and ballooning according to NAFLD activity score, serum aspartate aminotransferase and hyaluronic acid (HA) levels, and NAFLD Fibrosis Score (NFS). THBS2 was associated with extracellular matrix and collagen biosynthesis, platelet activation, caspase-mediated cleavage of cytoskeletal proteins, and immune cell infiltration. Serum TSP-2 expression was measured in 213 patients with biopsy-proven NAFLD, was significantly higher in NASH than in NAFL, and increased parallel to fibrosis stage. The AUROCs for predicting NASH and advanced fibrosis were 0.776 and 0.856, respectively, which were comparable to Fibrosis-4 index, serum HA level, and NFS in advanced fibrosis diagnosis. Serum TSP-2 level and platelet count were independent predictors of NASH and advanced Accepted ArticleThis article is protected by copyright. All rights reserved fibrosis. Serum TSP-2 levels could stratify NAFLD patients according to the risk of hepatic complications, including liver cancer and decompensated cirrhotic events.Conclusions: TSP-2 may be a useful biomarker for NASH and advanced fibrosis diagnosis in NAFLD patients.

Background and Aims: Immunotherapy has become the standard‐of‐care treatment for hepatocellular carcinoma (HCC), but its efficacy remains limited. To identify immunotherapy‐susceptible HCC, we profiled the molecular abnormalities and tumor immune microenvironment (TIME) of rapidly increasing nonviral HCC. Approaches and Results: We performed RNA‐seq of tumor tissues in 113 patients with nonviral HCC and cancer genome sequencing of 69 genes with recurrent genetic alterations reported in HCC. Unsupervised hierarchical clustering classified nonviral HCCs into three molecular classes (Class I, II, III), which stratified patient prognosis. Class I, with the poorest prognosis, was associated with TP53 mutations, whereas class III, with the best prognosis, was associated with cadherin‐associated protein beta 1 (CTNNB1) mutations. Thirty‐eight percent of nonviral HCC was defined as an immune class characterized by a high frequency of intratumoral steatosis and a low frequency of CTNNB1 mutations. Steatotic HCC, which accounts for 23% of nonviral HCC cases, presented an immune‐enriched but immune‐exhausted TIME characterized by T cell exhaustion, M2 macrophage and cancer‐associated fibroblast (CAF) infiltration, high PD‐L1 expression, and TGF‐β signaling activation. Spatial transcriptome analysis suggested that M2 macrophages and CAFs may be in close proximity to exhausted CD8+ T cells in steatotic HCC. An in vitro study showed that palmitic acid‐induced lipid accumulation in HCC cells upregulated PD‐L1 expression and promoted immunosuppressive phenotypes of cocultured macrophages and fibroblasts. Patients with steatotic HCC, confirmed by chemical‐shift MR imaging, had significantly longer PFS with combined immunotherapy using anti–PD‐L1 and anti‐VEGF antibodies. Conclusions: Multiomics stratified nonviral HCCs according to prognosis or TIME. We identified the link between intratumoral steatosis and immune‐exhausted immunotherapy‐susceptible TIME.

No abstract

No abstract

No abstract