BACKGROUND: Peripheral helper T (T PH ) cells are uniquely positioned within pathologically inflamed non-lymphoid tissues to stimulate B-cell responses and antibody production. However, the phenotype, function, and clinical relevance of T PH cells in hepatocellular carcinoma (HCC) are currently unknown. METHODS: Blood, tumor, and peritumoral liver tissue samples from 39 HCC patients (Sep 2016-Aug 2017) and 101 HCC patients (Sep 2011-Dec 2012) at the Third Affiliated Hospital of Sun Yat-sen University were used. Flow cytometry was used to quantify the expression, phenotype, and function of T PH cells. Log-rank tests were performed to evaluate disease-free survival and overall survival in samples from 39 patients and 101 patients with HCC. T PH cells, CD19 + B cells, and T follicular helper (T FH ) cells were cultured separately in vitro or isolated from C57/B6L mice in vivo for functional assays. RESULTS: T PH cells highly infiltrated tumor tissues, which was correlated with tumor size, early recurrence, and shorter survival time. The tumor-infiltrated T PH cells showed a unique ICOS hi CXCL13 + IL-21 - MAF + BCL-6 - phenotype and triggered naïve B-cell differentiation into regulatory B cells. Triggering programmed cell death protein 1 (PD-1) induced the production of C-X-C motif chemokine ligand 13 (CXCL13) by T PH cells, which then suppressed tumor-specific immunity and promoted disease progression. CONCLUSION Our study reveals a novel regulatory mechanism of T PH cell-regulatory B-cell-mediated immunosuppression and provides an important perspective for determining the balance between the differentiation of protumorigenic T PH cells and that of antitumorigenic T FH cells in the HCC microenvironment.
Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Humans ; T-Lymphocytes, Helper-Inducer/metabolism* ; Animals ; Mice ; Male ; Female ; Mice, Inbred C57BL ; Middle Aged ; B-Lymphocytes, Regulatory/metabolism* ; Flow Cytometry ; Interleukin-21 ; Aged ; Chemokine CXCL13/metabolism*

BACKGROUND: Cluster of differentiation 8 positive (CD8 + ) T cells play a crucial role in the response against tumors, including hepatocellular carcinoma (HCC), where their dysfunction is commonly observed. While the association between elevated peroxisome proliferator-activated receptor alpha (PPARα) expression in HCC cells and exosomes and unfavorable prognosis in HCC patients is well-established, the underlying biological mechanisms by which PPARα induces CD8 + T cell exhaustion mediated by HCC exosomes remain poorly understood. METHODS: Bioinformatics analyses and dual-luciferase reporter assays were used to investigate the regulation of microRNA-27b-3p ( miR-27b-3p ) and thymocyte selection-associated high mobility group box ( Tox ) by Pparα . In vitro and in vivo experiments were conducted to validate the effects of HCC-derived exosomes, miR-27b-3p overexpression, and Pparα on T cell function. Exosome characterization was confirmed using transmission electron microscopy, Western blotting, and particle size analysis. Exosome tracing was performed using small animal in vivo imaging and confocal microscopy. The expression levels of miR-27b-3p , Pparα , and T cell exhaustion-related molecules ( Tox , Havcr2 , and Pdcd1 ) were detected using quantitative reverse transcription polymerase chain reaction analysis, Western blotting analysis, immunofluorescence staining, and flow cytometry analysis. RESULTS: Pparα expression was significantly increased in HCC and negatively correlated with prognosis. It showed a positive correlation with Tox and a negative correlation with miR-27b-3p . The overexpressed Pparα from HCC cells was delivered to CD8 + T cells via exosomes, which absorbed miR-27b-3p both in vitro and in vivo , acting as "miRNA sponges". Further experiments demonstrated that Pparα can inhibit the negative regulation of Tox mediated by miR-27b-3p through binding to its 3'untranslated regions. CONCLUSIONS HCC-derived exosomes deliver Pparα to T cells and promote CD8 + T cell exhaustion and malignant progression of HCC via the miR-27b-3p /TOX regulatory axis. The mechanisms underlying T-cell exhaustion in HCC can be utilized for the advancement of anticancer therapies.
MicroRNAs/metabolism* ; PPAR alpha/genetics* ; Carcinoma, Hepatocellular/genetics* ; Humans ; Liver Neoplasms/genetics* ; CD8-Positive T-Lymphocytes/immunology* ; Exosomes/metabolism* ; Animals ; Cell Line, Tumor ; Mice ; High Mobility Group Proteins/genetics* ; Male ; T-Cell Exhaustion

Malignant proliferating liver cancer cells possess the ability to detect and respond to various body signals, thereby facilitating tumor growth, invasion, and metastasis. One crucial mechanism through which hepatocellular carcinoma (HCC) cells interpret these signals is crosstalk. Within liver cancer tissues, cancer cells engage in communication with hepatic stellate cells (HSCs), tumor-associated macrophages (TAMs), and immune cells. This interaction plays a pivotal role in regulating the proliferation, invasion, and metastasis of HCC cells. Crosstalk occurs in multiple ways, each characterized by distinct functions. Its molecular mechanisms primarily involve regulating immune cell functions through the expression of specific receptors, such as CD24 and CD47, modulating cell functions by secreting cytokines like transforming growth factor-β (TGF-β) and platelet-derived growth factor (PDGF), and mediating cell growth and proliferation by activating pathways such as Wnt/β-catenin and Hedgehog. A comprehensive understanding of the mechanisms and interactions within crosstalk is essential for unraveling the pathogenesis of HCC. It also opens up new avenues for the development of innovative therapeutic strategies. This article reviews the relationship between crosstalk and the progression of HCC, offering insights and inspiration for future research.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Hepatic Stellate Cells/physiology* ; Disease Progression ; Signal Transduction/physiology* ; Transforming Growth Factor beta/metabolism* ; Cell Proliferation ; Hedgehog Proteins/metabolism* ; Tumor-Associated Macrophages ; Platelet-Derived Growth Factor/metabolism* ; Cell Communication/physiology*

OBJECTIVES: To investigate the active ingredients in Hedyotis diffusa-Scutellaria barbata D. Don and the main biological processes and signaling pathways mediating their inhibitory effect on primary hepatocellular carcinoma (HCC). METHODS: The core intersecting genes of HCC and the two drugs were screened from TCMSP, Uniport, Genecards, and String databases using Cytoscape software, and GO and KEGG enrichment analyses of the intersecting genes were conducted. Molecular docking between the active ingredients of the drugs and the core genes was carried out using Pubcham, RCSB and Autoduckto to identify the active ingredients with the highest binding energy, whose inhibitory effect on HepG2 cells was verifies using CCK-8 assay, flow cytometry and Western blotting. RESULTS: TP53 and ESR1 were identified as the core genes of HCC and the two drugs. GO and KEGG analyses showed that the two genes were mainly involved in regulation of apoptotic signaling pathway, cell population proliferation, methane raft, and protein kinase activity, and participated in the signaling pathways of apoptosis, proteoglycans in cancer, PI3K Akt signaling pathway, and hepatitis B. Molecular docking studies showed that the active ingredients of the drugs could be docked with TP53 and ESR1 genes under natural conditions, and ursolic acid had the highest binding energy to ESR1 (-4.98 kcal/mol). The results of CCK-8 assay, flow cytometry and Western blotting all demonstrated significant inhibitory effect of ursolic acid on HepG2 cells. CONCLUSIONS The inhibitory effect of Hedyotis diffusa-scutellariae barbatae on HCC is mediated by multiple active ingredients in the two drugs.
Humans ; Molecular Docking Simulation ; Liver Neoplasms/drug therapy* ; Hep G2 Cells ; Network Pharmacology ; Carcinoma, Hepatocellular/drug therapy* ; Hedyotis/chemistry* ; Signal Transduction/drug effects* ; Cell Proliferation/drug effects* ; Tumor Suppressor Protein p53/metabolism* ; Apoptosis/drug effects* ; Estrogen Receptor alpha/metabolism* ; Drugs, Chinese Herbal/pharmacology*

OBJECTIVES: To investigate the clinical significance of SLC1A5 overexpression in pan-cancer and its mechanism for promoting hepatocellular carcinoma (HCC) progression. METHODS: We analyzed the correlation of SLC1A5 expression with clinical stage, lymph node metastasis and prognosis in pan-cancer using TCGA and ICGC datasets and explored its association with immune cell infiltration using EPIC, CIBERSORT, and TIMER algorithms. In HCC cell lines, the effects of lentivirus-mediated SLC1A5 overexpression or RNA interference on cell proliferation were examined using CCK-8 assay, and the growth of HCC cell xenografts overexpressing SLC1A5 was observed in nude mice. The effects of SLC1A5 overexpression or silencing in HCC cells on macrophage polarization were evaluated in a cell co-culture system. RESULTS: SLC1A5 was mainly localized on cell membrane and was highly expressed in most cancers in association with clinical stage, lymph node metastasis and poor prognosis. SLC1A5 expression was positively correlated with immunity score in 13 cancer types, especially in low-grade glioma (LGG), LIHC and thyroid cancer. SLC1A5 was positively correlated with macrophage infiltration level in LGG and LIHC but negatively correlated with macrophage infiltration in 5 cancers including lung squamous carcinoma, pancreatic carcinoma, and gastric carcinoma. Patients with SLC1A5 overexpression and high level of M2 macrophage infiltration had the worst survival outcomes. SLC1A5 was correlated with immunosuppression-related genes, cytokines, and cytokine receptors, which was the most obvious in LGG and LIHC. SLC1A5 was highly expressed in different HCC cell lines, and its overexpression promoted HCC cell proliferation both in vitro and in nude mice. In the cell co-culture experiment, SLC1A5 was positively correlated with the molecular markers of M2 polarization of macrophages, and its overexpression strongly promoted M2 polarization of the macrophages and inhibited T cell secretion of IFN-γ. CONCLUSIONS SLC1A5 expression level is correlated with clinical stage, lymph node metastasis, prognosis, and immune cell infiltration in most cancers, and its overexpression promotes HCC progression by inhibiting T-cell function via promoting M2 polarization of macrophages.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Animals ; Macrophages/cytology* ; Disease Progression ; Cell Line, Tumor ; Mice ; Amino Acid Transport System ASC/genetics* ; Cell Proliferation ; Lymphatic Metastasis ; Mice, Nude ; Prognosis ; Minor Histocompatibility Antigens

OBJECTIVES: To investigate the inhibitory effect of Zheng GanDecoction (ZGF) on tumor progression in a rat model of diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) and explore the possible mechanism. METHODS: Seventy SD rats were subjected to regular intraperitoneal injections of DEN (50 mg/kg) for 12 weeks to induce HCC tumorigenesis, with another 10 rats receiving saline injections as the normal control. After successful modeling, the rats were randomized into 5 groups (n=10) for daily treatment with distilled water ( model group), Huaier Granules (4 g/kg; positive control group), or ZGF at low, medium, and high doses (2, 4, and 8 g/kg, respectively) via gavage for 17 weeks. Body weight changes of the rats were monitored, and after completion of the treatments, the rats were euthanized for measurement of liver, spleen and thymus indices and morphological and histopathological examinations of the liver tissues using HE staining. The expressions of YAP, p-YAP, MST1, LATS1 and p-LATS1 in the liver tissues were detected using immunohistochemistry and Western blotting. RESULTS: Compared with the normal control rats, the rat models with DEN-induced HCC exhibited much poorer general condition with a significantly reduced survival rate, increased body weight and liver and spleen indices, and a lowered thymus index. ZGF treatment obviously reduced liver and spleen indices, increased the thymus index, and improved pathologies of the liver tissues of the rat models. Immunohistochemistry and Western blotting showed a dose-dependent reduction of YAP expression and an increment of p-YAP expression in ZGF-treated rats, which also exhibited significantly upregulated hepatic expressions of MST1, LATS1 and p-LATS1. CONCLUSIONS ZGF inhibits DEN-induced HCC in rats by activating the Hippo/YAP pathway via upregulating MST1 and LATS1 expression, which promotes YAP phosphorylation and degradation to suppress proliferation and induce apoptosis of the tumor cells.
Animals ; Drugs, Chinese Herbal/pharmacology* ; Diethylnitrosamine ; Rats, Sprague-Dawley ; Rats ; Signal Transduction/drug effects* ; Protein Serine-Threonine Kinases/metabolism* ; Carcinoma, Hepatocellular/drug therapy* ; YAP-Signaling Proteins ; Liver Neoplasms/drug therapy* ; Hippo Signaling Pathway ; Male ; Liver Neoplasms, Experimental/metabolism* ; Transcription Factors/metabolism* ; Adaptor Proteins, Signal Transducing/metabolism*

OBJECTIVES: To investigate the mechanism by which transforming growth factor‑β (TGF‑β) regulates major histocompatibility complex class I (MHC-I) expression in hepatocellular carcinoma (HCC) cells and its role in immune evasion of HCC. METHODS: HCC cells treated with TGF‑β alone or in combination with SB-431542 (a TGF-β type I receptor inhibitor) were examined for changes in MHC-I expression using RT-qPCR and Western blotting. A RNA interference experiment was used to explore the role of miR-23a-3p/IRF1 signaling in TGF‑β‑mediated regulation of MHC-I. HCC cells with different treatments were co-cultured with human peripheral blood mononuclear cells (PBMCs), and the changes in HCC cell proliferation was assessed using CCK-8 and colony formation assays. T-cell cytotoxicity in the co-culture systems was assessed with lactate dehydrogenase (LDH) release and JC-1 mitochondrial membrane potential assays, and T-cell activation was evaluated by flow cytometric analysis of CD69 cells and ELISA for TNF-α secretion. RESULTS: TGF‑β treatment significantly suppressed MHC-I expression in HCC cells and reduced T-cell activation, leading to increased tumor cell proliferation and decreased HCC cell death in the co-culture systems. Mechanistically, TGF-β upregulated miR-23a-3p, which directly targeted IRF1 to inhibit MHC-I transcription. Overexpression of miR-23a-3p phenocopied TGF‑β‑induced suppression of IRF1 and MHC-I. CONCLUSIONS We reveal a novel immune escape mechanism of HCC, in which TGF‑β attenuates T cell-mediated antitumor immunity by suppressing MHC-I expression through the miR-23a-3p/IRF1 signaling axis.
Humans ; MicroRNAs/genetics* ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Interferon Regulatory Factor-1/metabolism* ; Transforming Growth Factor beta/metabolism* ; Signal Transduction ; Histocompatibility Antigens Class I/metabolism* ; Cell Line, Tumor ; Tumor Escape ; Coculture Techniques

OBJECTIVES: To investigate the role of long noncoding RNA (lncRNA) HClnc1 in regulating proliferation, invasion, and migration of hepatocellular carcinoma (HCC) cells and the regulatory mechanism. METHODS: HClnc1 expression levels in liver cancer tissues were analyzed using data from the TCGA database. BrdU incorporation, plate cloning, and transwell assays were employed to examine the effects of HClnc1 silencing/overexpression and/or ODC1 silencing on proliferation, invasion, and migration of liver cancer cells. The effects of HClnc1 silencing on ODC1 protein and mRNA expression in the liver cancer cells were analyzed using qRT-PCR and Western blotting. The activity of ODC1 promoter was analyzed using a dual luciferase reporter gene assay. Pull-down experiment, mass spectrometry analysis, and chromatin immunoprecipitation (ChIP) assay were used for identification of HClnc1-binding proteins and their interactions. Protein interactions with the ODC1 promoter region and their binding efficiencies were investigated using RNA interference and ChIP analysis. RESULTS: HClnc1 was significantly overexpressed in HCC tissues. In liver cancer cells, HClnc1 silencing significantly inhibited cell proliferation, invasion, and migration, while HClnc1 overexpression promoted these behaviors. ODC1 silencing also suppressed malignant behaviors of liver cancer cells, and counteracted the effects of HClnc1 overexpression. Interference of HClnc1 obviously inhibited ODC1 promoter activity. RBBP5 and KAT2B proteins were identified to bind simultaneously with HClnc1. HClnc1 overexpression upregulated ODC1 protein expression, while interference of RBBP5 or KAT2B downregulated ODC1 protein expression and blocked HClnc1-induced upregulation of ODC1 protein. Both RBBP5 and KAT2B could directly bind to ODC1 promoter region; knocking out KAT2B or RBBP5 reduced the binding efficiency, while knocking out HClnc1 reduced the binding of both RBBP5 and KAT2B to ODC1 promoter region. CONCLUSIONS By targeting the RBBP5/KAT2B epigenetic modification complex, HClnc1 increases ODC1 promoter activity to enhance ODC1 transcription and promote the proliferation and migration of liver cancer cells.
Humans ; Cell Proliferation ; RNA, Long Noncoding/genetics* ; Cell Movement ; Liver Neoplasms/metabolism* ; Cell Line, Tumor ; Carcinoma, Hepatocellular/genetics* ; Promoter Regions, Genetic ; Gene Expression Regulation, Neoplastic

OBJECTIVES: To investigate the expression of parathyroid hormone-like hormone (PTHLH) in hepatocellular carcinoma (HCC) and analyze its correlation with clinical prognosis, its regulatory effects on HCC cell behaviors, and the signaling pathways mediating its effects. METHODS: We analyzed the differential expression of PTHLH in HCC and adjacent tissues and its association with patient prognosis based on data from TCGA and GEO databases and from 70 HCC patients treated in our hospital. The effects of PTHLH knockdown and overexpression on proliferation, migration, and invasion of cultured HCC cells were investigated using CCK-8 assay, colony formation assay, Transwell migration and invasion assays, and the signaling pathways activated by PTHLH were detected using Western blotting. RESULTS: TCGA and GEO database analysis showed significant overexpression of PTHLH mRNA in HCC tissues, which was associated with poor prognosis of the patients (P<0.05). High PTHLH mRNA expression was a probable independent prognostic risk factor for HCC (P<0.05). In the clinical samples, PTHLH mRNA and protein expressions were significantly higher in HCC tissues than in the adjacent tissues (P<0.001 or 0.01). Univariate and multivariate Cox regression analyses suggested that high PTHLH mRNA expression was an independent risk factor to affect postoperative disease-free survival of HCC patients (P<0.05). The prognostic prediction model based on PTHLH mRNA expression showed an improved accuracy for predicting the risk of postoperative recurrence in HCC patients. In cultured HCC cells, PTHLH overexpression significantly promoted cell proliferation, colony formation, migration and invasion, and caused activation of the ERK/JNK signaling pathway in Huh7 and Hep3B cells. CONCLUSIONS High PTHLH expression promotes HCC progression and is associated with poor patient prognosis. Its pro-tumor effects may be mediated by activation of the ERK/JNK signaling pathway.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Prognosis ; Cell Proliferation ; Parathyroid Hormone-Related Protein/genetics* ; Cell Line, Tumor ; Cell Movement ; Disease Progression ; Signal Transduction ; Male ; RNA, Messenger/genetics* ; Female

Deactivation of the mitochondrial pyruvate dehydrogenase complex (PDC) is important for the metabolic switching of cancer cell from oxidative phosphorylation to aerobic glycolysis. Studies examining PDC activity regulation have mainly focused on the phosphorylation of pyruvate dehydrogenase (E1), leaving other post-translational modifications largely unexplored. Here, we demonstrate that the acetylation of Lys 488 of pyruvate dehydrogenase complex component X (PDHX) commonly occurs in hepatocellular carcinoma, disrupting PDC assembly and contributing to lactate-driven epigenetic control of gene expression. PDHX, an E3-binding protein in the PDC, is acetylated by the p300 at Lys 488, impeding the interaction between PDHX and dihydrolipoyl transacetylase (E2), thereby disrupting PDC assembly to inhibit its activation. PDC disruption results in the conversion of most glucose to lactate, contributing to the aerobic glycolysis and H3K56 lactylation-mediated gene expression, facilitating tumor progression. These findings highlight a previously unrecognized role of PDHX acetylation in regulating PDC assembly and activity, linking PDHX Lys 488 acetylation and histone lactylation during hepatocellular carcinoma progression and providing a potential biomarker and therapeutic target for further development.
Humans ; Acetylation ; Carcinoma, Hepatocellular/genetics* ; Liver Neoplasms/genetics* ; Pyruvate Dehydrogenase Complex/genetics* ; Gene Expression Regulation, Neoplastic ; Animals ; Mice ; Cell Line, Tumor ; Protein Processing, Post-Translational ; Histones/metabolism* ; Disease Progression