Current status and perspectives of immune-based therapies for hepatocellular carcinoma

The role of inflammasomes in hepatocellular carcinoma: Mechanisms and therapeutic insights

Hepatocellular carcinoma is among the most frequent forms of primary liver cancer and develops within a context of chronic inflammation, frequently associated with a multitude of risk factors, including viral infections, metabolic dysfunction-associated fatty liver disease, metabolic dysfunction-associated steatohepatitis and liver fibrosis. The tumor microenvironment is crucial for the progression of HCC, as immune cells, tumor-associated fibroblasts and hepatic stellate cells interact to promote chronic inflammation and tumor spread. Inflammasomes, the multiprotein complexes that launch the innate immune response, emerge as important mediators in the pathogenesis of HCC. Among others, the inflammasome Nucleotide-binding oligomerization domain, Leucine rich Repeat (NLR) and Pyrin (NLRP) 3 (NLRP3), and absent in melanoma 2 (AIM2), exhibit a dual role in HCC background. It has been reported that they can exert oncosuppressive functions by triggering the inflammatory death of cancer cells. Vice versa, chronic activation contributes to the development of a pro-tumorigenic environment, thus supporting tumor growth. In addition, other inflammasomes such as Nucleotide-binding oligomerization domain, Leucine rich Repeat (NLR) and Pyrin (NLRP) 6 and 12 (NLRP6 and NLRP12, respectively) regulate HCC onset and progression, although more experimental evidence is required. This review focuses on the molecular mechanisms underpinning the inflammasome's contribution to the onset, progression and spread of HCC. Moreover, we will explore the potential therapeutic approaches currently under investigation, which aim to improve the efficacy and reduce the side effects of the treatments currently available. Targeting inflammasomes may be a promising therapeutic strategy for the treatment of HCC, offering new opportunities to improve patient prognosis.

Sensitizing the Efficiency of ICIs by Neoantigen mRNA Vaccines for HCC Treatment

This study builds upon the groundbreaking mRNA vaccine Nobel Prize win in 2023 for COVID-19 prevention, paving the way for next-generation mRNA cancer vaccines to revolutionize immunotherapy. Despite the existing challenges, such as the presence of a suppressive tumor microenvironment and the identification of cancer-associated antigens, recent results from the KEYNOTE-942 trial have successfully demonstrated the effectiveness of mRNA-based cancer treatments, providing clinical evidence for the first time. This trial aimed to evaluate the efficacy and safety of combining immune checkpoint inhibitors with mRNA-based therapies in treating cancer. This advancement undeniably represents new hope for hepatocellular carcinoma (HCC) patients. However, progress in this field remains limited. In this article, we summarized the current state of applying immune checkpoint inhibitors (ICIs) combined with neoantigen mRNA vaccines. Additionally, we discussed potential targets for designing novel mRNA vaccines and potential mRNA vaccine delivery vehicles. The objective of this article is to inspire enthusiasm for the exploration of innovative therapeutic strategies that combine ICIs with neoantigen mRNA vaccines for HCC treatment and HCC prevention.

Systematic analyses to explore immune gene sets-based signature in hepatocellular carcinoma, in which IGF2BP3 contributes to tumor progression

Tumor immune microenvironment (TIME) is of critical importance for the development and therapeutic response of hepatocellular carcinoma (HCC). However, limited studies have investigated immune-related indicators for clinical supervision and decision. The current study aimed to develop an improved prognostic signature based on TIME. HCC patients from TCGA and ICGC database were classified into three subtypes (Immunity High, Immunity Medium and Immunity Low) according to ssGSEA scores of 29 immune gene sets. Differentially expressed immune-related genes (DE IRGs) between Immune High and Low groups were screened with an adjusted P < 0.05. Weighted gene co-expression network analysis (WGCNA) was used to establish gene co-expression modules of differentially expressed genes (DEGs) between tumor and normal tissues. 45 survival-related immune genes (SRIGs) were identified at points of intersection between hub genes and DE IRGs. By performing Cox regression and LASSO analysis, 3 of the 45 SRIGs were screened to establish a prognostic model. Patients with high risk scores exhibited worse survival outcome and poorer response to chemotherapy. Potential mechanisms of chemotherapy resistance also have been discussed. More significantly, high -risk patients showed increased immune cell infiltration and checkpoints, which suggested a benefit of immunotherapy. In addition, knockdown of IGF2BP3 was determined to significantly inhibit cell proliferation and migration in HCC. Our immune-related model may be an effective tool for precise diagnosis and treatment of HCC. It may help to select patients suitable for chemotherapy, and immunotherapy.

Stereotactic navigation versus ultrasound guidance in placing IRE applicators in a liver phantom

The aim of this study was to compare the accuracy of stereotactic CT-guided navigation and ultrasound guided navigation for placing electrodes in Irreversible electroporation in a liver phantom. A liver phantom with multiple tumours was used and interventionists placed four IRE electrodes around each tumour guided either by stereotactic CT-guided navigation or ultrasound. The goal was to place them in a perfect 20 × 20 mm square with parallel electrodes. After each treatment, a CT-scan was performed. The accuracy in pairwise electrode distance, pairwise parallelism and time per tumour was analysed. Eight interventionists placed four electrodes around 55 tumours, 25 with ultrasound and 30 with stereotactic CT-guided navigation. 330 electrode pairs were analysed, 150 with ultrasound and 180 with stereotactic CT-navigation. The absolute median deviation from the optimal distance was 1.3 mm (range 0.0 to 11.3 mm) in the stereotactic CT-navigation group versus 7.1 mm (range 0.3 to 18.1 mm) in the Ultrasound group (p < 0.001). The mean angle between electrodes in each pair was 2.7 degrees (95% CI 2.4 to 3.1 degrees) in the stereotactic CT-navigation group and 5.5 degrees (95% CI 5.0 to 6.1 degrees) in the Ultrasound group (p < 0.001). The mean time for placing the electrodes was 15:11 min (95% CI 13:05 to 17:18 min) in the stereotactic CT-navigation group and 6:40 min (95% CI 5:28 to 7:52 min) in the Ultrasound group. The use of stereotactic CT-navigation in placing IRE-electrodes in a liver phantom is more accurate, but more time consuming, compared to ultrasound guidance.

Tamarix articulata Inhibits Cell Proliferation, Promotes Cell Death Mechanisms and Triggers G0/G1 Cell Cycle Arrest in Hepatocellular Carcinoma Cells

RESEARCH BACKGROUND

From ancient times plants have been used for medicinal purposes against various ailments. In the modern era, plants are a major source of drugs and are an appealing drug candidate for the anticancer therapeutics against various molecular targets. Here we tested methanolic extract of dry leaves of Tamarix articulata for anticancer activity against a panel of hepatocellular carcinoma cells.

EXPERIMENTAL APPROACH

Cell viability of hepatocellular carcinoma cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after a dose-dependent treatment with the extract of T. articulata. Phase-contrast microscopy and 4՛,6-diamidino-2-phenylindole (DAPI) staining served to analyse cellular and nuclear morphology. Immunoblotting was performed to determine the expression of proteins associated with autophagy, apoptosis and cell cycle. However, flow cytometry was used for the quantification of apoptotic cells and the analysis of cells in different phases of the cycle after the treatment with various doses of T. articulata. Additionally, acridine orange staining and 2՛,7՛-dichlorofluorescein diacetate (DCFH-DA) dye were used to analyse the quantification of autophagosomes and reactive oxygen species.

RESULTS AND CONCLUSION

Our results demonstrate that T. articulata methanolic extract exhibits promising antiproliferative activity with IC50 values (271.1±4.4), (298.3±7.1) and (336.7±6.1) µg/mL against hepatocellular carcinoma HepG2, Huh7D12 and Hep3B cell lines, respectively. Mechanistically, we found that T. articulata methanolic extract induces cell death by activating apoptosis and autophagy pathways. First, T. articulata methanolic extract promoted autophagy, which was confirmed by acridine orange staining. The immunoblotting analysis further confirmed that the extract at higher doses consistently induced the conversion of LC3I to LC3II form with a gradual decrease in the expression of autophagy substrate protein p62. Second, T. articulata methanolic extract promoted reactive oxygen species production in hepatocellular carcinoma cells and activated reactive oxygen species-mediated apoptosis. Flow cytometry and immunoblotting analysis showed that the plant methanolic extract induced dose-dependent apoptosis and activated proapoptotic proteins caspase-3 and PARP1. Additionally, the extract triggered the arrest of the G0/G1 phase of the cell cycle and upregulated the protein expression of p27/Kip and p21/Cip, with a decrease in cyclin D1 expression in hepatocellular carcinoma cells.

NOVELTY AND SCIENTIFIC CONTRIBUTION

The current study demonstrates that T. articulata methanolic extract exhibits promising anticancer potential to kill tumour cells by programmed cell death type I and II mechanisms and could be explored for potential drug candidate molecules to curtail cancer in the future.

Adjuvant therapy using ex vivo-expanded allogenic natural killer cells in hepatectomy patients with hepatitis B virus related solitary hepatocellular carcinoma: MG4101 study

Backgrounds/Aims

Fewer reports have been published regarding hepatectomy patients with solitary hepatocellular carcinoma (HCC) who received immunotherapeutic agents as adjuvant therapy. We evaluated the safety and efficacy of ex vivo-expanded allogenic natural killer (NK) cells in those patients with modified International Union Against Cancer (UICC) stage T3.

Methods

From August 2014 to October 2015, five patients who underwent hepatic resection received ex vivo-expanded allogenic NK cells. Patients received five rounds of NK cells (2-3×10⁷ cells/kg) at postoperative 4, 6, 8, 12, and 16 weeks. This study is registered with ClinicalTrials.gov, number NCT02008929.

Results

The median age of the five patients (three men and two women) was 44.8 years (range, 36-54 years). All had hepatitis B virus-related HCC, and the median tumor size was 2.2 cm (range, 2.1-8.2 cm). None of the patients had any adverse events. HCC recurrence developed in two patients at one year after hepatic resection, but four patients were alive at 3 years. The two recurrence-free patients showed a higher ratio of CD8+ T lymphocyte populations before and after administration of ex vivo-expanded allogenic NK cells compared with the three patients who experienced recurrence.

Conclusions

Immunotherapy using ex vivo-expanded allogenic NK cells in hepatectomy patients can be used safely. Further studies should be investigated for efficacy.

Minimally invasive ethyl cellulose ethanol ablation in domesticated cats with naturally occurring head and neck cancers: Six cats

It is difficult to retain tumoricidal doses of ethanol in large or unencapsulated tumours without causing intoxication or damaging surrounding tissue. Ethyl cellulose-ethanol ablation (ECEA) overcomes this limitation by trapping ethanol intratumorally. To evaluate the safety of ECEA and to develop a clinically feasible workflow, a single-arm pilot study was performed in cats with lingual/sublingual squamous cell carcinoma (SCC). Six cats underwent intratumoral injection of 6% ethyl cellulose in ethanol. Subjects were observed overnight. There was mild bleeding and transient hyperthermia, and injection site pain and swelling that improved with anti-inflammatory drugs. Serum ethanol was minimally elevated; the mean concentration peaked 1 hour after injection (129 +/- 15.1 nM). Cats were rechecked at weeks 1 and 2; booster treatments were given in cats (n = 3) with stable quality of life and partial response to therapy. Recheck examinations were then performed monthly. The longest tumour dimension increased in each animal (progressive disease via cRECIST); however, estimated tumour volume was reduced in 3 of 6 cats, within 1 week of ECEA. All cats were euthanized (median survival time 70 days) because of local tumour progression and/or lingual dysfunction that was likely hastened by ECEA. ECEA is not a viable treatment for feline lingual/sublingual SCC; tumour volume was effectively reduced in some cats, but the simultaneous loss of lingual function was poorly tolerated. Further optimization may make ECEA a useful option for SCC at other oral sites in the cat, and for head and neck malignancies in other species.

Accuracy of Electrode Placement in IRE Treatment with Navigated Guidance

Purpose

Evaluate the accuracy of multiple electrode placements in IRE treatment of liver tumours using a stereotactic CT-based navigation system.

Method

Analysing data from all IRE treatments of liver tumours at one institution until 31 December 2018. Comparing planned with validated electrode placement. Analysing lateral and angular errors and parallelism between electrode pairs

Results

Eighty-four tumours were treated in 60 patients. Forty-six per cent were hepatocellular carcinoma, and 36% were colorectal liver metastases. The tumours were located in all segments of the liver. Data were complete from 51 treatments. Two hundred and six electrodes and 336 electrode pairs were analysed. The median lateral and angular error, comparing planned and validated electrode placement, was 3.6 mm (range 0.2–13.6 mm) and 3.1° (range 0°–16.1°). All electrodes with a lateral error >10 mm were either re-positioned or excluded before treatment. The median angle between the electrode pairs was 3.8° (range 0.3°–17.2°). There were no electrode placement-related complications.

Conclusion

The use of a stereotactic CT-based system for navigation of electrode placement in IRE treatment of liver tumours is safe, accurate and user friendly.

Long Non-Coding RNAs: Potential Biomarkers and Targets for Hepatocellular Carcinoma Therapy and Diagnosis

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. Increasing studies showed that long non-coding RNAs (lncRNAs), a novel class of RNAs that are greater than 200 nucleotides in length but lack the ability to encode proteins, exert crucial roles in the occurrence and progression of HCC. LncRNAs promote the proliferation, migration, invasion, autophagy, and apoptosis of tumor cells by regulating downstream target gene expression and cancer-related signaling pathways. Meanwhile, lncRNA can be used as biomarkers to predict the efficacy of HCC treatment strategies, such as surgery, radiotherapy, chemotherapy, and immunotherapy, and as a potential individualized tool for HCC diagnosis and treatment. In this review, we overview up-to-date findings on lncRNAs as potential biomarkers for HCC surgery, radiotherapy, chemotherapy resistance, target therapy, and immunotherapy, and discuss the potential clinical application of lncRNA as tools for HCC diagnosis and treatment.

Immuno-oncology for Hepatocellular Carcinoma: The Present and the Future

Hepatocellular carcinoma is a highly prevalent and lethal cancer that many therapeutics are being tested for this disease. It has the potential to be a highly immune-responsive tumor given its inflammatory origins. The first immunotherapies were anti-programmed death-1 monotherapies, which improved response rates and survival. Novel immunotherapy combinations and immunotherapy show promise in frontline treatment. The novel antibody therapy combination of atezolizumab and bevacizumab may be practice changing. Although these landmark studies seem to offer new treatment options, the role of immunotherapy in the liver transplant setting is uncertain until the safety of this approach is defined.

Microwave ablation enhances tumor-specific immune response in patients with hepatocellular carcinoma

Thermal ablative therapies are standard treatments for localized hepatocellular carcinoma (HCC). In addition to local tumor destruction, ablation leads to abscopal effects in distant lesions most likely mediated by an anti-tumor immune response. Although microwave ablation (MWA) is increasingly substituting other ablative techniques, its systemic immunostimulatory effects are poorly studied. We analyzed tumor-specific immune responses in peripheral blood of HCC patients after thermal ablation with regard to T cell responses and disease outcome. While comprehensive flow cytometric analyses in sequential samples of a prospective patient cohort (n = 23) demonstrated only moderate effects of MWA on circulating immune cell subsets, fluorospot analyses of specific T cell responses against seven tumor-associated antigens (TTAs) revealed de-novo or enhanced tumor-specific immune responses in 30% of patients. This anti-tumor immune response was related to tumor control as Interferon-y and Interleukin-5 T cell responses against TAAs were more frequent in patients with a long-time remission (> 1 year) after MWA (7/16) compared to patients suffering from an early relapse (0/13 patients) and presence of tumor-specific T cell response (IFN-y and/or IL-5) was associated to longer progression-free survival (27.5 vs. 10.0 months). Digital image analysis of immunohistochemically stained archival HCC samples (n = 18) of patients receiving combined MWA and resection revealed a superior disease-free survival of patients with high T cell abundance at the time of thermal ablation (37.4 vs. 13.1 months). Our data demonstrates remarkable immune-related effects of MWA in HCC patients and provides additional evidence for a combination of local ablation and immunotherapy in this challenging disease.

A genomic-clinical nomogram predicting recurrence-free survival for patients diagnosed with hepatocellular carcinoma

Liver resection surgery is the most commonly used treatment strategy for patients diagnosed with hepatocellular carcinoma (HCC). However, there is still a chance for recurrence in these patients despite the survival benefits of this procedure. This study aimed to explore recurrence-related genes (RRGs) and establish a genomic-clinical nomogram for predicting postoperative recurrence in HCC patients. A total of 123 differently expressed genes and three RRGs (PZP, SPP2, and PRC1) were identified from online databases via Cox regression and LASSO logistic regression analyses and a gene-based risk model containing RRGs was then established. The Harrell’s concordance index (C-index), receiver operating characteristic (ROC) curves and calibration curves showed that the model performed well. Finally, a genomic-clinical nomogram incorporating the gene-based risk model, AJCC staging system, and Eastern Cooperative Oncology Group performance status was constructed to predict the 1-, 2-, and 3-year recurrence-free survival rates (RFS) for HCC patients. The C-index, ROC analysis, and decision curve analysis were good indicators of the nomogram’s performance. In conclusion, we identified three reliable RRGs associated with the recurrence of cancer and constructed a nomogram that performed well in predicting RFS for HCC patients. These findings could enrich our understanding of the mechanisms for HCC recurrence, help surgeons predict patients’ prognosis, and promote HCC treatment.

Are There Upper Limits in Tumor Burden for Down-Staging of Hepatocellular Carcinoma to Liver Transplant? Analysis of the All-Comers Protocol

Patients with hepatocellular carcinoma (HCC) within the University of California, San Francisco down-staging (UCSF-DS) criteria (one lesion > 5 cm and ≤ 8 cm; two to three lesions each ≤ 5 cm; or four to five lesions each ≤ 3 cm with total tumor diameter ≤ 8 cm) who achieved successful down-staging (DS) to Milan criteria had similar outcomes after liver transplantation (LT) compared with HCC initially meeting the Milan criteria. Nevertheless, little is known about the outcome of DS in patients with initial tumor burden exceeding the UCSF-DS criteria, defined as "all-comers" (AC). We compared the intention-to-treat (ITT) outcomes of DS in 74 patients in the AC group and 133 patients in the UCSF-DS group. Successful DS to Milan was observed in 64.8% of the AC group versus 84.2% of the UCSF-DS group (P < 0.001). The sum of tumor number and largest tumor diameter was significantly associated with successful DS (hazard ratio [HR] 0.87, P < 0.05). The cumulative probability of dropout within 1 year and 3 years was 53.5% and 80.0%, respectively, for AC versus 25.0% and 36.1%, respectively, for UCSF-DS (P < 0.0001). Factors predicting dropout included sum of tumor number and largest tumor diameter greater than 8 (HR 1.79, P = 0.049) and Child class B and C (HR 2.54, P = 0.001). The AC group also had a significantly lower liver transplant (LT) rate (13.5% versus 59.0%, P < 0.001). ITT survival at 1 year and 5 years was 77.4% and 21.1%, respectively, in AC versus 85.5% and 56.0%, respectively, in UCSF-DS (P < 0.001). Three of 10 patients in the AC group who underwent LT developed HCC recurrence. Conclusion: We observed a significantly lower LT probability and inferior ITT survival with DS in the AC group versus the UCSF-DS group. Our results suggest that an upper limit in tumor burden exists beyond which successful LT after DS becomes an unrealistic goal.

Treatment of Advanced Hepatocellular Carcinoma with Somatostatin Analogues: A Review of the Literature

Hepatocellular carcinoma, one of the most dreaded complications of cirrhosis, is a frequent cancer with high mortality. Early primary liver cancer can be treated by surgery or ablation techniques, but advanced hepatocellular carcinoma remains a challenge for clinicians. Most of these patients have underlying cirrhosis, which complicates or even precludes treatment. Therefore, efficacious treatments without major side effects are welcomed. Initial results of treatment of advanced hepatocellular carcinoma with somatostatin analogues were promising, but subsequent trials have resulted in conflicting outcomes. This might be explained by different patient populations, differences in dosage and type of treatment and differences in somatostatin receptor expression in the tumor or surrounding tissue. It has been shown that the expression of somatostatin receptors in the tumor might be of importance to select patients who could benefit from treatment with somatostatin analogues. Moreover, somatostatin receptor expression in hepatocellular carcinoma has been shown to correlate with recurrence, prognosis, and survival. In this review, we will summarize the available data on treatment of primary liver cancer with somatostatin analogues and analyze the current knowledge of somatostatin receptor expression in hepatocellular carcinoma and its possible clinical impact.

Immunotherapy and the Interventional Oncologist: Challenges and Opportunities-A Society of Interventional Oncology White Paper

Interventional oncology is a subspecialty field of interventional radiology that addresses the diagnosis and treatment of cancer and cancer-related problems by using targeted minimally invasive procedures performed with image guidance. Immuno-oncology is an innovative area of cancer research and practice that seeks to help the patient's own immune system fight cancer. Both interventional oncology and immuno-oncology can potentially play a pivotal role in cancer management plans when used alongside medical, surgical, and radiation oncology in the care of cancer patients.

Initial experience with irreversible electroporation of liver tumours

Introduction

Thermal ablation of liver tumours is an established technique used in selected patients with relatively small tumours that can be ablated with margin. Thermal ablation methods are not advisable near larger bile ducts that are sensitive to thermal injury causing strictures and severe morbidity. Irreversible electroporation (IRE) has the possibility to treat these tumours without harming the bile tree. The method is relatively new and has been proven to be feasible and safe with promising oncological results.

Methods

50 treatments were performed on 42 patients that were not resectable or treatable by thermal ablation (12 women and 30 men) with 59 tumours in total. 51% were colorectal cancer liver metastases (CRCLM) and 34% were hepatocellular carcinomas (HCC). 70% of the treatments were performed using stereotactic CT-guidance for needle placement.

Results

81% of the treatments were performed with initial success. All patients with missed ablations were re-treated. Local recurrence rate at 3 months was 3% and 37% at one year. The complication rate was low with 2 patients having major complications (Clavien-Dindo grade 3b-5) and without 30-day mortality.

Conclusion

IRE is safe for treating tumours not suitable for thermal ablation with 63% of patients being without local recurrence after one year in a group of patients with tumours deemed unresectable. IRE has a role in the treatment of unresectable liver tumours close to heat-sensitive structures not suitable for thermal ablation.

Level of Evidence: Level 4, Case Series.

Down-regulation of siglec-2 (CD22) predicts worse overall survival from HBV-related early-stage hepatocellular carcinoma: a preliminary analysis from Gene Expression Omnibus

Sialic-acid-binding immunoglobulin-like lectin (siglec) regulates cell death, anti-proliferative effects and mediates a variety of cellular activities. Little was known about the relationship between siglecs and hepatocellular carcinoma (HCC) prognosis. Siglec gene expression between tumor and non-tumor tissues were compared and correlated with overall survival (OS) from HCC patients in GSE14520 microarray expression profile. Siglec-1 to siglec-9 were all down-regulated in tumor tissues compared with those in non-tumor tissues in HCC patients (all P < 0.05). Univariate and multivariate Cox regression analysis revealed that siglec-2 overexpression could predict better OS (HR = 0.883, 95%CI = 0.806-0.966, P = 0.007). Patients with higher siglec-2 levels achieved longer OS months than those with lower siglec-2 levels in the Kaplan-Meier event analysis both in training and validation sets (P < 0.05). Alpha-fetoprotein (AFP) levels in siglec-2 low expression group were significantly higher than those in siglec-2 high expression group using Chi-square analysis (P = 0.043). In addition, both logistic regression analysis and ROC curve method showed that siglec-2 down-regulation in tumor tissues was significantly associated with AFP elevation over 300 ng/ml (P < 0.05). In conclusion, up-regulation of siglec-2 in tumor tissues could predict better OS in HCC patients. Mechanisms of siglec-2 in HCC development need further research.

Transcriptomic analysis of hepatocellular carcinoma reveals molecular features of disease progression and tumor immune biology

Hepatocellular carcinoma (HCC) develops in the context of chronic inflammatory liver disease and has an extremely poor prognosis. An immunosuppressive tumor microenvironment may contribute to therapeutic failure in metastatic HCC. Here, we identified unique molecular signatures pertaining to HCC disease progression and tumor immunity by analyzing genome-wide RNA-Seq data derived from HCC patient tumors and non-tumor cirrhotic tissues. Unsupervised clustering of gene expression data revealed a gradual suppression of local tumor immunity that coincided with disease progression, indicating an increasingly immunosuppressive tumor environment during HCC disease advancement. IHC examination of the spatial distribution of CD8+ T cells in tumors revealed distinct intra- and peri-tumoral subsets. Differential gene expression analysis revealed an 85-gene signature that was significantly upregulated in the peri-tumoral CD8+ T cell-excluded tumors. Notably, this signature was highly enriched with components of underlying extracellular matrix, fibrosis, and epithelial-mesenchymal transition (EMT). Further analysis condensed this signature to a core set of 23 genes that are associated with CD8+ T cell localization, and were prospectively validated in an independent cohort of HCC specimens. These findings suggest a potential association between elevated fibrosis, possibly modulated by TGF-β, PDGFR, SHH or Notch pathway, and the T cell-excluded immune phenotype. Indeed, targeting fibrosis using a TGF-β neutralizing antibody in the STAM™ model of murine HCC, we found that ameliorating the fibrotic environment could facilitate redistribution of CD8+ lymphocytes into tumors. Our results provide a strong rationale for utilizing immunotherapies in HCC earlier during treatment, potentially in combination with anti-fibrotic therapies.

Chimeric antigen receptor-engineered T-cell therapy for liver cancer

BACKGROUND

Chimeric antigen receptor-engineered T-cell (CAR-T) therapy is a newly developed immunotherapy used in the treatment of cancers. Because CAR-T therapy has shown great success in treating CD19-positive hematological malignancies, its application has been explored in the treatment of solid tumors, such as liver cancer. In this review, we discuss the immune characteristics of liver cancer, the obstacles encountered during the application of CAR-T therapy, and preclinical and clinical progress in the use of CAR-T therapy in patients with liver cancer.

DATA SOURCES

The data on CAR-T therapy related to liver cancers were collected by searching PubMed and the Web of Science databases prior to December 2017 with the keywords "chimeric antigen receptor", "CAR-T", "liver cancer", "hepatocellular carcinoma", and "solid tumor". Additional articles were identified by manual search of references found in the primary articles. The data for clinical trials were collected by searching ClinicalTrials.gov.

RESULTS

The liver has a tolerogenic nature in the intrahepatic milieu and its tumor microenvironment significantly affects tumor progression. The obstacles that reduce the efficacy of CAR-T therapy in solid tumors include a lack of specific tumor antigens, limited trafficking and penetration of CAR-T cells to tumor sites, and an immunosuppressive tumor microenvironment. To overcome these obstacles, several strategies have emerged. In addition, several strategies have been developed to manage the side effects of CAR-T, including enhancing the selectivity of CARs and controlling CAR-T activity. To date, no clinical trials of CAR-T therapy against HCC have been completed. However, preclinical studies in vitro and in vivo have shown potent antitumor efficacy. Glypican-3, mucin-1, epithelial cell adhesion molecule, carcinoembryonic antigen, and other targets are currently being studied.

CONCLUSIONS

The application of CAR-T therapy for liver cancer is just beginning to be explored and more research is needed. However, we are optimistic that CAR-T therapy will offer a new approach for the treatment of liver cancers in the future.

When and how should we perform a biopsy for HCC in patients with liver cirrhosis in 2018? A review

The role of liver biopsy in the diagnosis of hepatocellular carcinoma (HCC) has changed over time. The diagnostic algorithm for this tumor is nowadays mainly based on radiological imaging, relegating histology to controversial cases, in which imaging techniques cannot establish a clear-cut diagnosis. This most commonly happens in small lesions, where biopsies frequently become mandatory, or in larger hypovascularized lesions. In this case however, the histological examination may not be reliable enough to grade the lesion, as different cell clones, deriving from sequential mutations, can originate heterogeneous cell populations. The risk of complications of liver biopsy, such as tumor seeding and intra-abdominal bleeding, needs to be reconsidered in light of new scientific evidence and of the technical improvements that have been introduced. Furthermore, increasing knowledge of the immunohistochemical and molecular characteristics of hepatocellular carcinoma opens a new scenario in which biopsy may play a decisive role in defining prognosis, and even treatment, by identifying the patient populations who could most benefit from target-driven hepatocellular carcinoma treatments, and therefore improving the success rate of experimental therapies. All the above reasons suggest that, overall, the role of liver biopsy in the management of HCC needs a reappraisal.

Six2 is negatively correlated with good prognosis and decreases 5-FU sensitivity via suppressing E-cadherin expression in hepatocellular carcinoma cells

This work aims to study the roles and related mechanisms of six2 in 5-FU sensitivity of hepatocellular carcinoma (HCC) cells. KM-Plotter analysis showed that HCC patients with higher six2 expression levels had shorter overall survival. Six2 expression was higher in clinical HCC tissues than in normal tissues, and was negatively correlated with E-cadherin expression. Additionally, six2 overexpression decreased the sensitivity of HCC cells to 5-Fu, characterized as attenuating 5-FU-induced cell apoptosis and downregulation of cell viability, and promoted HCC cells stemness. Mechanistically, six2 overexpression repressed E-cadherin expression via stimulating promoter methylation of the E-cadherin. And E-cadherin overexpression rescued six2-induced decrease of 5-FU sensitivity and promotion on HCC cells stemness. Therefore, our results suggest that Six2 is negatively correlated with good prognosis and decreases 5-FU sensitivity via suppressing E-cadherin expression in HCC cells.

MiR-544 promotes immune escape through downregulation of NCR1/NKp46 via targeting RUNX3 in liver cancer

Objective

To study the potential role of miR-544 in the immune escape mechanism of hepatoma cells.

Methods

Natural killer (NK) cells were collected from healthy volunteers and patients with liver cancer. Interleukin (IL)-2 activated-NK-92 cells were transfected with miR-544 inhibitor/mimic or NC/pre-NC in HepG2 co-culture system. NK-92 cells were treated with control, IL-2, IL-2 + pre-NC, IL-2 + miR-544 mimic, IL-2 + miR-544 mimic + pcDNA and IL-2 + miR-544 mimic + pcDNA-runt-related transcription factor 3 (RUNX3) groups. Mice models of liver cancer were well established. Expression of miR-544, natural cytotoxicity receptor 1 (NCR1) and RUNX3 were evaluated by quantitative real-time PCR and western blotting. Flow cytometry and ELISA were used to determine NK cell cytotoxicity and the levels of INF-γ, respectively.

Results

MiR-544 was upregulated while NCR1 and RUNX3 was downregulated in NK cells of patients with liver cancer. The levels of IFN-γ and miR-544 expression were increased and decreased in IL-2 activated-NK cells, respectively. Inversely, miR-544 overexpression inhibited NK cell cytotoxicity by downregulating IFN-γ. However, miR-544 directly targeted RUNX3 and negatively regulated NCR1. Furthermore, miR-544 promoted immune escape of hepatoma cells in vivo and in vitro.

Conclusion

miR-544 promoted the immune escape of liver cancer cells by downregulating NCR1 via targeting RUNX3.

Dual inhibitors of hepatitis C virus and hepatocellular carcinoma: design, synthesis and docking studies

Aim

Simultaneous inhibition of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC) may enhance anti-HCV effects and reduce resistance and side effects.

Results/methodology

Novel hybrid derivatives were designed and synthesized to exhibit dual activity against HCV and its associated major complication, HCC. The synthesized compounds were screened for their potential activity against HCV and HCC. Compounds 5f, 5j, 5l, 5p, 5q, 5r, 6c and 6d exhibited potential in vitro anticancer activity against HCC cell line HepG2, while compounds 5a, 5l, 5p and 5v showed in vitro anti-HCV activity. Docking studies suggested that the newly synthesized compounds could suppress HCC through VEGFR2 tyrosine kinase inhibition.

Conclusion

Compounds 5l and 5p exhibited dual activity against HCV and HCC in vitro.

Using a weaning immunosuppression protocol in liver transplantation recipients with hepatocellular carcinoma: a compromise between the risk of recurrence and the risk of rejection?

Hepatocellular carcinoma (HCC) recurrence rate after liver transplantation (LT) is still up to 15-20%, despite a careful selection of candidates and optimization of the management within the waiting list. To reduce tumour recurrence, the currently adopted post-transplant strategies are based on the administration of a tailored immunosuppression (IS) regimen. Drug-induced depression of the immune system is essential in preventing graft rejection, however has a well-established association with oncogenesis. The immune system has a key role as a defending mechanism against cancer development, preventing vascular invasion and metastasis. Thus, IS drugs represent one of few modifiable non-oncological risk factors for tumour recurrence. In HCC recipients, a tailored IS therapy, with the aim to minimize drugs' doses, is essential to gain the optimal balance between the risk of rejection and the risk of tumour recurrence. So far, a complete withdrawal of IS drugs after LT is reported to be safely achievable in 25% of patients (defined as "operational tolerant"), without the risk of patient and graft loss. The recent identification of non-invasive "bio-markers of tolerance", which permit to identify patients who could successfully withdraw IS therapies, opens new perspectives in the management of HCC after LT. IS withdrawal could potentially reduce the risk of tumour recurrence, which represents the major drawback in HCC recipients. Herein, we review the current literature on IS weaning in patients who underwent LT for HCC as primary indication and we report the largest experiences on IS withdrawal in HCC recipients.

HLA-mediated tumor escape mechanisms that may impair immunotherapy clinical outcomes via T-cell activation

Although the immune system provides protection from cancer by means of immunosurveillance, which serves a major function in eliminating cancer cells, it may also lead to cancer immunoediting, molding tumor immunogenicity. Cancer cells exploit several molecular mechanisms to thwart immune-mediated death by disabling cellular components of the immune system associated with tumor recognition and rejection. Human leukocyte antigen (HLA) molecules are mandatory for the immune recognition and subsequent killing of neoplastic cells by the immune system, as tumor antigens must be presented in an HLA-restricted manner to be recognized by T-cell receptors. Impaired HLA-I expression prevents the activation of cytotoxic immune mechanisms, whereas impaired HLA-II expression affects the antigen-presenting capability of antigen presenting cells. Aberrant HLA-G expression by cancer cells favors immune escape by inhibiting the activities of virtually all immune cells. The development of cancer therapies based on T-cell activation must consider these HLA-associated immune evasion mechanisms, as alterations in their expression occur early and frequently in the majority of types of cancer, and have an adverse impact on the clinical response to immunotherapy. Herein, the concept of altered HLA expression as a mechanism exploited by tumors to escape immune control and induce an immunosuppressive environment is reviewed. A number of novel clinical immunotherapeutic approaches used for cancer treatment are also reviewed, and strategies for overcoming the limitations of these immunotherapeutic interventions are proposed.

Surface expression of anti-CD3scfv stimulates locoregional immunotherapy against hepatocellular carcinoma depending on the E1A-engineered human umbilical cord mesenchymal stem cells

Tumor antigens is at the core of cancer immunotherapy, however, the ideal antigen selection is difficult especially in poorly immunogenic tumors. In this study, we designed a strategy to modify hepatocellular carcinoma (HCC) cells by surface expressing anti-CD3scfv within the tumor site strictly, which depended on the E1A-engineered human umbilical cord mesenchymal stem cells (HUMSC.E1A) delivery system. Subsequently, membrane-bound anti-CD3scfv actived the lymphocytes which lysed HCC cells bypassing the expression of antigens or MHC restriction. First, we constructed the anti-CD3scfv gene driven by human α-fetoprotein (AFP) promoter into an adenoviral vector and the E1A gene into the lentiviral vector. Our results showed that anti-CD3scfv could specifically express on the surface of HCC cells and activate the lymphocytes to kill target cells effectively in vitro. HUMSC infected by AdCD3scfv followed by LentiR.E1A could support the adenoviral replication and packaging in vitro 36 h after LentiR.E1A infection. Using a subcutaneous HepG2 xenograft model, we confirmed that AdCD3scfv and LentiR.E1A co-transfected HUMSC could migrate selectively to the tumor site and produce considerable adenoviruses. The new generated AdCD3scfv infected and modified tumor cells successfully. Mice injected with the MSC.E1A.AdCD3scfv and lymphocytes significantly inhibited the tumor growth compared with control groups. Furthermore, 5-fluorouracil (5-FU) could sensitize adenovirus infection at low MOI resulting in improved lymphocytes cytotoxicity in vitro and in vivo. In summary, this study provides a promising strategy for solid tumor immunotherapy.

Fluid shear stress regulates HepG2 cell migration though time-dependent integrin signaling cascade

Hepatocellular carcinoma (HCC) is a subtype of malignant liver cancer with poor prognosis and limited treatment options. It is noteworthy that mechanical forces in tumor microenvironment play a pivotal role in mediating the behaviors and functions of tumor cells. As an instrumental type of mechanical forces in vivo, fluid shear stress (FSS) has been reported having potent physiologic and pathologic effects on cancer progression. However, the time-dependent mechanochemical transduction in HCC induced by FSS remains unclear. In this study, hepatocellular carcinoma HepG2 cells were exposed to 1.4 dyn/cm² FSS for transient duration (15s and 30s), short duration (5 min, 15 min and 30 min) and long duration (1h, 2h and 4h), respectively. The expression and translocation of Integrins induced FAK-Rho GTPases signaling events were examined. Our results showed that FSS endowed HepG2 cells with higher migration ability via reorganizing cellular F-actin and disrupting intercellular tight junctions. We further demonstrated that FSS regulated the expression and translocation of Integrins and their downstream signaling cascade in time-dependent patterns. The FSS downregulated focal adhesion components (Paxillin, Vinculin and Talin) while upregulated the expression of Rho GTPases (Cdc42, Rac1 and RhoA) in long durations. These results indicated that FSS enhanced tumor cell migration through Integrins-FAK-Rho GTPases signaling pathway in time-dependent manners. Our in vitro findings shed new light on the role of FSS acting in physiologic and pathological processes during tumor progression, which has emerged as a promising clinical strategy for liver carcinoma.

B lymphocytes repress hepatic tumorigenesis but not development in Hras12V transgenic mice

Increasing reports show noninflammation underlying HCC, challenging our understanding of the roles of the immune system in hepatocarcinogenesis. By exploring a mouse model of hepatic tumor induced by hepatocyte-specific expression of the Hras12V oncogene without obvious inflammation, we found that the proportion of B cells, but not T cells, progressively and significantly decreased in 3, 5-month-old transgenic mice (Tg) compared with non-transgenic mice. Notably, the proportions of total and activated B and T cells all significantly decreased in 9-month-old Tg with multiple massive hepatic tumors. Together with the decreased B cell proportion, serum IgG1/2 also significantly decreased in 5, 9-month-old Tg. Interestingly, homozygous Tg showed significantly higher B cell proportion and IgG2 levels, accompanied by significantly lower incidences of liver nodules but not adenomas and carcinomas compared with heterozygous Tg. Treatment of Tg with PCI-32765, a potent Bruton's tyrosine kinase (BTK) inhibitor for suppressing B cell proliferation and activation, significantly decreased the B cell proportion and IgG2 levels, accompanied by a significantly higher incidence of liver nodules, but had no effects on adenoma and carcinoma. Treatment of Tg with insulin-like growth factor 1 (IGF-1) significantly increased the B cell proportion and IgG2 levels, accompanied by a significantly lower incidence of liver nodules and carcinoma, but had no effects on adenoma. Conclusively, B cells and IgG2 may play important roles in suppressing hepatic tumorigenesis, but not development. In addition, hepatocyte-specific expression of the ras oncogene may play roles in suppressing B cells, while developed hepatic tumors suppress both B and T cells.

Immunotherapeutic approaches for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a cancer with a high mortality rate due to the fact that the diagnosis usually occurs at anadvanced stage. Even in case of curative surgical treatment, recurrence is common. Sorafenib and regorafenib are the only therapeutic agents that have been demonstrated to be effective in advanced HCC, thus novel curative approaches are urgently needed. Recent studies focus on the role of immune system in HCC. In fact, the unique immune response in the liver favors tolerance, which can represent a real challenge for conventional immunotherapy in these patients. Spontaneous immune responses against tumor antigens have been detected, and new immune therapies are under investigation: dendritic cell vaccination, immune-modulator strategy, and immune checkpoint inhibition. In recent years different clinical trials examining the use of immunotherapy to treat HCC have been conducted with initial promising results. This review article will summarize the literature data concerning the potential immunotherapeutic approaches in HCC patients.

Systemic treatment for hepatocellular carcinoma: Still unmet expectations

Many patients with hepatocellular carcinoma (HCC) are diagnosed in an advanced stage, so they cannot be offered the option of curative treatments. The results of systemic chemotherapy are unsatisfactory and this has led to molecular targeted approaches. HCC develops in chronically damaged tissue due to cirrhosis in most patients. Several different cell types and molecules constitute a unique microenvironment in the liver, which has significant implications in tumor development and invasion. This, together with genome instability, contributes to a significant heterogeneity which is further enhanced by the molecular differences of the underlying causes. New classifications based on genetic characteristics of the tissue microenvironment have been proposed and key carcinogenic signaling pathways have been described. Tumor and adjacent tissue profiling seem biologically promising, but have not yet been translated into clinical settings. The encouraging first results with molecular - genetic signatures should be validated and clinically applicable. A more personalized approach to modern management of HCC is urgently needed.

Is Adjuvant Cellular Immunotherapy Essential after TACE-Predominant Minimally-Invasive Treatment for Hepatocellular Carcinoma? A Systematic Meta-Analysis of Studies Including 1774 Patients

PURPOSE

Cellular immunotherapy has appeared to be a promising modality for the treatment of malignant tumor. The objective of this study was to evaluate the efficacy of cellular immunotherapy combined with minimally invasive therapy.

METHODS

We searched PubMed, Web of Science and The Cochrane Library through March 2016 for relevant studies. Short-term efficacy (the disease control rate, the control rate of quality life and the AFP descent rate) and long-term efficacy (overall survival (OS) and progression-free survival (PFS) rate) were compared as the major outcome measures. The meta-analysis was performed using Review Manager 5.3.

RESULTS

A total of 1174 references in 3 databases were found of which 19 individual studies with 1774 HCC patients enrolled in this meta-analysis. Meta-analysis results showed that cellular immunotherapy combined with minimally-invasive treatment significantly improved the measures of short-term response (the disease control rate (OR = 5.91, P = 0.007), the control rate of quality lift (OR = 3.38, P = 0.003) and the AFP descent rate (OR = 4.48, P = 0.02)). Also higher 6-month PFS (OR = 2.78, P = 0.05), ≥12-month PFS (OR = 3.56, P<0.00001) rate and 6-month OS (OR = 2.81, P = 0.0009), 12-month OS (OR = 3.05, P<0.00001) and 24-month OS (OR = 3.52, P<0.0001) rate were observed in patients undergoing cellular immunotherapy.

CONCLUSIONS

This meta-analysis suggested that cellular immunotherapy is a feasible adjuvant treatment that could be beneficial for the improvement of the clinical outcomes for hepatocellular carcinoma (HCC) patients after minimally invasive treatment, including short-term response and long-term survival.

Frequently mutated genes/pathways and genomic instability as prevention targets in liver cancer

The incidence of liver cancer has increased in recent years. Worldwide, liver cancer is common: more than 600000 related deaths are estimated each year. In the USA, about 27170 deaths due to liver cancer are estimated for 2016. Liver cancer is highly resistant to conventional chemotherapy and radiotherapy. For all stages combined, the 5-year survival rate is 15-17%, leaving much to be desired for liver cancer prevention and therapy. Heterogeneity, which can originate from genomic instability, is one reason for poor outcome. About 80-90% of liver cancers are hepatocellular carcinoma (HCC), and recent cancer genome sequencing studies have revealed frequently mutated genes in HCC. In this review, we discuss the cause of the tumor heterogeneity based on the functions of genes that are frequently mutated in HCC. We overview the functions of the genes that are most frequently mutated (e.g. TP53, CTNNB1, AXIN1, ARID1A and WWP1) that portray major pathways leading to HCC and identify the roles of these genes in preventing genomic instability. Notably, the pathway analysis suggested that oxidative stress management may be critical to prevent accumulation of DNA damage and further mutations. We propose that both chromosome instability (CIN) and microsatellite instability (MIN) are integral to the hepatic carcinogenesis process leading to heterogeneity in HCC and that the pathways leading to heterogeneity may be targeted for prognosis, prevention and treatment.