Ex-vivo expanded CD34+ cell transplantation alleviates fibrotic liver injury via innate immune modulation in metabolic dysfunction-associated steatohepatitis mice.

BACKGROUND: In drug-induced liver injury, vascular endothelial progenitor cells, specifically the CD34+ cell fractions, have been found to decrease liver fibrosis and promote regeneration. However, it is unclear whether CD34+ cell transplantation has anti-fibrogenic effects on MASH, which has previously been treated effectively with anti-angiogenic therapy. We investigated the efficacy of ex vivo-expanded CD34+ cells in treating MASH livers. MATERIALS AND METHODS: Diet-induced MASH mice were fed a choline-deficient, L-amino acid-defined, high-fat diet for 12 or 20 weeks, and were designated as a mild and a severe fibrosis model, respectively. Mouse bone marrow CD34+ cells were expanded for 7 days, transplanted into each mouse once or twice 2 weeks later, and sacrificed at 4 weeks after the first transplantation. RESULTS: Expanded CD34+ cell transplantation ameliorated liver fibrosis, regardless of fibrosis degree, as indicated by the decrease in α-smooth muscle actin-positive cells, hydroxyproline concentration, and fibrogenic gene expression of Col1a1 and Timp1. Furthermore, engrafted CD34+ cells reduced alanine transaminase levels, the number of TUNEL+ hepatocytes, and 8-OHdG concentration. RNA-sequencing data showed that "defense response to virus" was the most down-regulated category in the Gene Ontology analysis and subsequent analysis revealed the suppression of RIG-I-like receptors/Irf7/Stat1/Cxcl10 axis in expanded CD34+ cell-transplanted livers. Finally, the downregulation of CXCL10 expression inhibits the mobilization of inflammatory immune cells, macrophages, T cells, and natural killer cells to the MASH liver. CONCLUSIONS: These findings suggest that transplanted expanded CD34+ cells alleviate fibrotic liver injury in MASH mouse models through possible modulation of the innate immune response, which is abnormally activated by hepatocyte lipotoxicity.

A tumor endothelial cell-specific microRNA replacement therapy for hepatocellular carcinoma.

Current approved anti-angiogenic drugs (AAD) for hepatocellular carcinoma (HCC) inhibit tumor angiogenesis, but affect the hepatic vasculature resulting in adverse effects. Tumor endothelial cells (TECs) differ from normal endothelial cells. In this study, we aimed to detect TEC-specific miRNAs and develop an anti-angiogenic treatment specific for TECs. We established HCC orthotopic mouse models. TEC-specific miRNAs were detected using a microRNA array. Finally, we evaluated the therapeutic effects of the TEC-specific miRNA agonist cocktail. In total, 260 TEC-specific genes were detected. Among the top ten downregulated TEC-specific miRNAs, miR-139-3p and 214-3p were important for the TEC phenotype. The TEC-specific microRNA agonist cocktail showed significant anti-tumor effects by inhibiting tumor angiogenesis without affecting hepatic vasculatures in HCC orthotopic mouse models. Moreover, it significantly downregulated tip-cell sprouting-related genes. We identified two downregulated TEC-specific miRNAs; microRNA replacement therapy, which targets the downregulated TEC-specific miRNAs, is an effective and promising treatment for HCC.

Fibroblast growth factor inhibition by molecular-targeted agents mitigates immunosuppressive tissue microenvironment in hepatocellular carcinoma.

BACKGROUND & AIMS: Combination immunotherapy refers to the use of immune checkpoint inhibitors (ICI) and molecular-targeted agents (MTA), which have recently been approved for the treatment of advanced hepatocellular carcinoma (HCC). Owing to its relatively low antitumor effect (up to 30%), sequential therapy following ICIs treatment is required in patients with HCC. This study aimed to determine the impact of MTAs on the tumor immune microenvironment (TIME). METHODS: We established immune syngeneic orthotopic HCC mouse models using Hep-55.1C and Hep-53.4, and treated them with MTAs (lenvatinib, sorafenib, regorafenib, cabozantinib, and DC101 as anti-vascular endothelial growth factor receptor-2 antibodies, and AZD4547 as a fibroblast growth factor receptor (FGFR)-1/2/3/4 inhibitor) for 2 weeks. Subsequently, alterations in the TIME caused by MTAs were evaluated using immunohistochemistry (antibodies for CD3, CD8, Foxp3, Granzyme B, Arginase-1, NK1.1, F4/80, CD11c, PD-1, and PD-L1). We conducted RNA-seq analysis using lenvatinib- and AZD4547-treated tumors. To confirm the clinical relevance of these findings, we analyzed the transcriptome data of human HCC cells (MHCC-97H) treated with various concentrations of lenvatinib for 24 h using RNA-seq data from the Gene Expression Omnibus database. RESULTS: The number of Foxp3- and F4/80-positive cells in the TIME was decreased in many MTAs. Cabozantinib increased the numbers in NK1.1-, Granzyme B, and CD11c-positive cells. Lenvatinib and AZD4547 increased the number of CD8, Granzyme B, and PD-L1-positive cells. Gene ontology enrichment analysis revealed that lipid metabolism-related genes were downregulated by lenvatinib and AZD4547. In total, 161 genes downregulated by FGFR inhibition in rodent models overlapped with those downregulated by lenvatinib in human HCC cells. CONCLUSIONS: In this study, we showed that cabozantinib activated the innate immune system, and lenvatinib and AZD4547, which commonly inhibit FGFR signaling, altered TIME to a hot immune state by downregulating lipid metabolism-related genes. These findings support the therapeutic use of combination immunotherapies.

Tumor-derived insulin-like growth factor-binding protein-1 contributes to resistance of hepatocellular carcinoma to tyrosine kinase inhibitors.

BACKGROUND: Antiangiogenic tyrosine kinase inhibitors (TKIs) provide one of the few therapeutic options for effective treatment of hepatocellular carcinoma (HCC). However, patients with HCC often develop resistance toward antiangiogenic TKIs, and the underlying mechanisms are not understood. The aim of this study was to determine the mechanisms underlying antiangiogenic TKI resistance in HCC. METHODS: We used an unbiased proteomic approach to define proteins that were responsible for the resistance to antiangiogenic TKIs in HCC patients. We evaluated the prognosis, therapeutic response, and serum insulin-like growth factor-binding protein-1 (IGFBP-1) levels of 31 lenvatinib-treated HCC patients. Based on the array of results, a retrospective clinical study and preclinical experiments using mouse and human hepatoma cells were conducted. Additionally, in vivo genetic and pharmacological gain- and loss-of-function experiments were performed. RESULTS: In the patient cohort, IGFBP-1 was identified as the signaling molecule with the highest expression that was inversely associated with overall survival. Mechanistically, antiangiogenic TKI treatment markedly elevated tumor IGFBP-1 levels via the hypoxia-hypoxia inducible factor signaling. IGFBP-1 stimulated angiogenesis through activation of the integrin α5ß1-focal adhesion kinase pathway. Consequently, loss of IGFBP-1 and integrin α5ß1 by genetic and pharmacological approaches re-sensitized HCC to lenvatinib treatment. CONCLUSIONS: Together, our data shed light on mechanisms underlying acquired resistance of HCC to antiangiogenic TKIs. Antiangiogenic TKIs induced an increase of tumor IGFBP-1, which promoted angiogenesis through activating the IGFBP-1-integrin α5ß1 pathway. These data bolster the application of a new therapeutic concept by combining antiangiogenic TKIs with IGFBP-1 inhibitors.

Ex vivo expansion of circulating CD34(+) cells enhances the regenerative effect on rat liver cirrhosis.

Ex vivo expansion of autologous cells is indispensable for cell transplantation therapy of patients with liver cirrhosis. The aim of this study was to investigate the efficacy of human ex vivo-expanded CD34(+) cells for treatment of cirrhotic rat liver. Recipient rats were intraperitoneally injected with CCl4 twice weekly for 3 weeks before administration of CD34(+) cells. CCl4 was then re-administered twice weekly for 3 more weeks, and the rats were sacrificed. Saline, nonexpanded or expanded CD34(+) cells were injected via the spleen. After 7 days, CD34(+) cells were effectively expanded in a serum-free culture medium. Expanded CD34(+) cells were also increasingly positive for cell surface markers of VE-cadherin, VEGF receptor-2, and Tie-2. The expression of proangiogenic growth factors and adhesion molecules in expanded CD34(+) cells increased compared with nonexpanded CD34(+) cells. Expanded CD34(+) cell transplantation reduced liver fibrosis, with a decrease of αSMA(+) cells. Assessments of hepatocyte and sinusoidal endothelial cell proliferative activity indicated the superior potency of expanded CD34(+) cells over non-expanded CD34(+) cells. The inhibition of integrin αvß3 and αvß5 disturbed the engraftment of transplanted CD34(+) cells and aggravated liver fibrosis. These findings suggest that expanded CD34(+) cells enhanced the preventive efficacy of cell transplantation in a cirrhotic model.