Abstract Ectopic hepatocellular carcinoma (EHCC) is an extremely rare neoplasm, especially in the mediastinum, which shares morphologic characteristics with intrahepatic hepatocellular carcinoma (HCC). Its clinical features remain unclear, posing significant diagnostic and therapeutic challenges. The prognosis is also unclear due to its rarity and potential variability. This study reports the first case of EHCC in the mediastinum with subsequent brain metastasis. A 50-year-old man presented with shoulder and chest discomfort persisting for 5 months, accompanied by progressive weight loss and fatigue over the preceding 2 years. Imaging showed a mediastinal mass initially suspected to be lymphoma due to its malignant characteristics. However, histopathological examination identified the lesion as HCC, supported by characteristic immunohistochemical markers, despite normal abdominal imaging. Two months later, the tumor progressed despite intensive radiotherapy, and the patient experienced recurrent seizures. Subsequent brain imaging confirmed multiple intracranial metastases. Unfortunately, the patient died 6 months after diagnosis. The ectopic liver is more susceptible to hepatocarcinogenesis than the main liver; this is attributed to its incomplete functional structure. EHCC can be considered as differential diagnosis of mediastinal masses, even when no intrahepatic HCC is found. The rarity of EHCC in the mediastinum poses difficulties in developing treatment protocols. This case emphasizes the diagnostic challenges and aggressive nature of ectopic HCC and the need for comprehensive management strategies. There are currently no definite guidelines regarding the diagnosis, treatment, and prognosis of EHCC.
ectopic hepatocellular carcinoma ; mediastinum ; metastasis

This study aimed to investigate the regulatory effect and mechanism of thymopentin on the growth of subcutaneous hepatocellular carcinoma in mice. A subcutaneous tumor model of Hepa1-6 liver cancer in immunocompetent mice was constructed, with three randomly divided groups based on tumor volume: control group, low-dose thymopentin (TP5) group (10 mg/kg), and high-dose TP5 group (20 mg/kg), with 6 mice in each group. Drugs were administered, and the intervention effect of thymopentin on tumor growth was evaluated. Hepa1-6 cells were then cultured in vitro and treated with blank medium and TP5 of different concentrations (10, 100, 1000 ng/mL) for 72 hours. Cell viability was detected by sulforhodamine B (SRB) colorimetry. A subcutaneous tumor model of liver cancer LM3 in immunocompromised mice was constructed, with three randomly divided groups based on tumor volume: control group, TP5 group (20 mg/kg), and positive drug Sorafinib group (30 mg/kg). The intervention effect of thymopentin on the growth of subcutaneous tumors in immunocompromised mice was evaluated. Flow cytometry was used to analyze the changes in the proportion of T cells and myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment 11 days after TP5 administration in the Hepa1-6 model. MDSCs were cultured in vitro and treated with TP5. The effect of TP5 on MDSCs was evaluated by detecting the levels of ROS, IL-6, and NO, which are effector molecules of MDSCs. The mouse subcutaneous liver cancer model was established again using C57BL/6N mice. After 10 days, they were randomly divided into four groups based on tumor volume: control group, low-dose TP5 group (10 mg/kg), high-dose TP5 group (20 mg/kg), and arginine-deficient TP5 group (15 mg/kg). Drugs were administered continuously for 11 days, and the intervention effect of arginine-deficient TP5 on tumor growth was evaluated based on tumor weight. Annexin-V staining was used to detect the impact of TP5 on T cell survival. The results showed that both low and high doses of TP5 inhibited the growth of subcutaneous liver cancer in immunocompetent mice (P < 0.05), yet TP5 had no direct inhibitory effect on the proliferation of tumor cells cultured in vitro. Besides, a high dose of TP5 could not inhibit the growth of subcutaneous liver cancer in immunocompromised mice. Furthermore, TP5 promoted the infiltration of CD4 and CD8 T cells but decreased MDSCs in the subcutaneous tumor microenvironment of immunocompetent mice. TP5 did not affect the levels of ROS, IL-6, and NO in MDSCs. Lastly, arginine-deficient TP5 could not inhibit the growth of subcutaneous liver cancer in immunocompetent mice. Accordingly, TP5 but not arginine-deficient TP5 promoted the increase in the proportion of viable CD4 and CD8 T cells cultured in vitro. These results suggest that TP5 may inhibit the growth of liver cancer by increasing T cell number in the liver cancer microenvironment.
thymopentin ; hepatocellular carcinoma ; tumor microenvironment ; arginine ; T cells

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*

The study investigated the specific mechanism by which oxocrebanine, the anti-hepatic cancer active ingredient in Stephania hainanensis, inhibits the proliferation of hepatic cancer cells. Firstly, methyl thiazolyl tetrazolium(MTT) assay, 5-bromodeoxyuridine(BrdU) labeling, and colony formation assay were employed to investigate whether oxocrebanine inhibited the proliferation of HepG2 and Hep3B2.1-7 cells. Propidium iodide(PI) staining was used to observe the oxocrebanine-induced apoptosis of HepG2 and Hep3B2.1-7 cells. Western blot was employed to verify whether apoptotic effector proteins, such as cleaved cysteinyl aspartate-specific protease 3(c-caspase-3), poly(ADP-ribose) polymerase 1(PARP1), B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), Bcl-2 homologous killer(Bak), and myeloid cell leukemia-1(Mcl-1) were involved in apoptosis. Secondly, HepG2 cells were simultaneously treated with oxocrebanine and the autophagy inhibitor 3-methyladenine(3-MA), and the changes in the autophagy marker LC3 and autophagy-related proteins [eukaryotic translation initiation factor 4E-binding protein 1(4EBP1), phosphorylated 4EBP1(p-4EBP1), 70-kDa ribosomal protein S6 kinase(P70S6K), and phosphorylated P70S6K(p-P70S6K)] were determined. The results of MTT assay, BrdU labeling, and colony formation assay showed that oxocrebanine inhibited the proliferation of HepG2 and Hep3B2.1-7 cells in a dose-dependent manner. The results of flow cytometry suggested that the apoptosis rate of HepG2 and Hep3B2.1-7 cells increased after treatment with oxocrebanine. Western blot results showed that the protein levels of c-caspase-3, Bax, and Bak were up-regulated and those of PARP1, Bcl-2, and Mcl-1 were down-regulated in the HepG2 cells treated with oxocrebanine. The results indicated that oxocrebanine induced apoptosis, thereby inhibiting the proliferation of hepatic cancer cells. The inhibition of HepG2 cell proliferation by oxocrebanine may be related to the induction of protective autophagy in hepatocellular carcinoma cells. Oxocrebanine still promoted the conversion of LC3-Ⅰ to LC3-Ⅱ, reduced the phosphorylation levels of 4EBP1 and P70S6K, which can be reversed by the autophagy inhibitor 3-MA. It is prompted that oxocrebanine can inhibit the proliferation of hepatic cancer cells by inducing autophagy. In conclusion, oxocrebanine inhibits the proliferation of hepatic cancer cells by inducing apoptosis and autophagy.
Humans ; Apoptosis/drug effects* ; Autophagy/drug effects* ; Cell Proliferation/drug effects* ; Hep G2 Cells ; Liver Neoplasms/genetics* ; Carcinoma, Hepatocellular/genetics* ; Caspase 3/genetics*

This study investigates the effect of glycyrrhetinic acid(GA) combined with doxorubicin(DOX) on apoptosis in HepG2 cells and its possible mechanisms. HepG2 cells were cultured in vitro, and cell viability was assessed using the cell counting kit-8(CCK-8) method. Flow cytometry was used to measure apoptosis levels in HepG2 cells. The cells were divided into the following groups: control group(0 μmol·L~(-1)), DOX group(2 μmol·L~(-1)), GA group(150 μmol·L~(-1)), and DOX + GA combination group(2 μmol·L~(-1) DOX + 150 μmol·L~(-1) GA), with treatments given for 24 hours. The colocalization level between the endoplasmic reticulum(ER) and mitochondria was assessed by colocalization fluorescence imaging. Fluorescence probes were used to measure the Ca~(2+) content in the ER and mitochondria. The qRT-PCR and Western blot were used to determine the mRNA and protein expression of sirtuin-3(SIRT3). Co-immunoprecipitation(CO-IP) was applied to investigate the interactions between voltage-dependent anion channel 1(VDAC1) and SIRT3, as well as between VDAC1, glucose-regulated protein 75(GRP75), and inositol 1,4,5-trisphosphate receptor(IP3R). The results showed that the combination of DOX and GA promoted apoptosis in HepG2 liver cancer cells. The colocalization level between the ER and mitochondria was significantly reduced, the Ca~(2+) content in the ER was significantly increased, and the Ca~(2+) content in the mitochondria was significantly decreased. The relative expression of VDAC1, GRP75, and IP3R was significantly reduced, and interactions between VDAC1, GRP75, and IP3R were observed. SIRT3 mRNA and protein expression levels were significantly increased, and an interaction between SIRT3 and VDAC1 was detected. The acetylation level of VDAC1 was significantly decreased. In conclusion, GA combined with DOX induces apoptosis in HepG2 cells by mediating the deacetylation of VDAC1 through SIRT3, weakening the interactions among VDAC1, GRP75, and IP3R. This regulates the formation of endoplasmic reticulum-mitochondrial membrane domains(ERMMDs), affects Ca~(2+) transport between the ER and mitochondria, and ultimately triggers cell apoptosis.
Humans ; Apoptosis/drug effects* ; Hep G2 Cells ; Glycyrrhetinic Acid/pharmacology* ; Doxorubicin/pharmacology* ; Liver Neoplasms/genetics* ; Carcinoma, Hepatocellular/physiopathology* ; Mitochondria/metabolism* ; Endoplasmic Reticulum/metabolism* ; Cell Survival/drug effects* ; Membrane Proteins/genetics*

Hepatocellular carcinoma(HCC), the third leading cause of cancer-related death worldwide, is characterized by high mortality and recurrence rates. Common treatments include hepatectomy, liver transplantation, ablation therapy, interventional therapy, radiotherapy, systemic therapy, and traditional Chinese medicine(TCM). While exhibiting specific advantages, these approaches are associated with varying degrees of adverse effects. To alleviate patients' suffering and burdens, it is crucial to explore additional treatments and elucidate the pathogenesis of HCC, laying a foundation for the development of new TCM-based drugs. With emerging research on gut microbiota, it has been revealed that microbiota plays a vital role in the development of HCC by influencing intestinal barrier function, microbial metabolites, and immune regulation. TCM, with its multi-component, multi-target, and multi-pathway characteristics, has been increasingly recognized as a vital therapeutic treatment for HCC, particularly in patients at intermediate or advanced stages, by prolonging survival and improving quality of life. Recent global studies demonstrate that TCM exerts anti-HCC effects by modulating gut microbiota, restoring intestinal barrier function, regulating microbial composition and its metabolites, suppressing inflammation, and enhancing immune responses, thereby inhibiting the malignant phenotype of HCC. This review aims to elucidate the mechanisms by which gut microbiota contributes to the development and progression of HCC and highlight the regulatory effects of TCM, addressing the current gap in systematic understanding of the "TCM-gut microbiota-HCC" axis. The findings provide theoretical support for integrating TCM with western medicine in HCC treatment and promote the transition from basic research to precision clinical therapy through microbiota-targeted drug development and TCM-based interventions.
Humans ; Gastrointestinal Microbiome/drug effects* ; Carcinoma, Hepatocellular/microbiology* ; Liver Neoplasms/microbiology* ; Drugs, Chinese Herbal/administration & dosage* ; Animals ; Medicine, Chinese Traditional

Objective To explore the clinical and immunological significance of CCDC97 in hepatocellular carcinoma (HCC). Methods Clinical data and RNA sequencing results from HCC patients were retrieved from TCGA and ICGC databases. Bioinformatics analysis and in vitro experiments were performed to investigate the role of CCDC97 in HCC. Results The expression level of CCDC97 was elevated in HCC patients and HCC cells, closely associated with pathological features and prognosis. CCDC97 was identified as a novel prognostic biomarker. It is linked to the spliceosome pathway, which is significantly active in tumors and potentially promotes carcinogenesis. CCDC97 is also highly expressed in various immune cells and is associated with microenvironment. Furthermore, knocking down CCDC97 in vitro suppressed cell migration, invasion, and proliferation. Conclusion CCDC97 plays a critical role in HCC progression and the immune microenvironment, making it a potential target for prognosis and therapeutic intervention.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Tumor Microenvironment/genetics* ; Cell Movement/genetics* ; Cell Proliferation ; Prognosis ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Biomarkers, Tumor/genetics* ; Male

Hepatocellular carcinoma (HCC) is one of the fastest growing cancers in the world, ranking fourth among the causes of cancer-induced death in the world. At present, the field of HCC treatment is developing rapidly, and immunotherapy has been recognized as a promising treatment method, in which T cells play a key role in HCC immunotherapy. However, in the case of virus infection or in tumor microenvironment (TME), T cells will be continuously stimulated by antigens and then fall into the state of T cell exhaustion (Tex). This state will not only reduce the immunity of patients but also lead to poor efficacy of immunotherapy. Therefore, to deeply analyze the mechanism of Tex and to explore effective strategies to reverse Tex is the key point in the immunotherapy for HCC. This review aims to summarize the mechanism of Tex in HCC patients, and the current situation and shortcomings of drug research and development to reverse Tex at this stage, in order to provide theoretical basis for the optimization of immunotherapy regimen for HCC patients.
Humans ; Carcinoma, Hepatocellular/therapy* ; Liver Neoplasms/therapy* ; Immunotherapy/methods* ; T-Lymphocytes/immunology* ; Tumor Microenvironment/immunology* ; Animals ; T-Cell Exhaustion