The Current Landscape of Immune Checkpoint Blockade in Hepatocellular Carcinoma: A Review

The Systemic Inflammatory Response Identifies Patients with Adverse Clinical Outcome from Immunotherapy in Hepatocellular Carcinoma

Systemic inflammation is a hallmark of cancer, and it has a pivotal role in hepatocellular carcinoma (HCC) development and progression. We conducted a retrospective study including 362 patients receiving immune check-point inhibitors (ICIs) across three continents, evaluating the influence of neutrophiles to lymphocytes ratio (NLR), platelets to lymphocytes ratio (PLR), and prognostic nutritional index (PNI) on overall (OS), progression free survival (PFS), and radiologic responses. In our 362 patients treated with immunotherapy, median OS and PFS were 9 and 3.5 months, respectively. Amongst tested inflammatory biomarkers, patients with NLR ≥ 5 had shorter OS (7.7 vs. 17.6 months, p < 0.0001), PFS (2.1 vs. 3.8 months, p = 0.025), and lower objective response rate (ORR) (12% vs. 22%, p = 0.034); similarly, patients with PLR ≥ 300 reported shorter OS (6.4 vs. 16.5 months, p < 0.0001) and PFS (1.8 vs. 3.7 months, p = 0.0006). NLR emerged as independent prognostic factors for OS in univariate and multivariate analysis (HR 1.95, 95%CI 1.45-2.64, p < 0.001; HR 1.73, 95%CI 1.23-2.42, p = 0.002) and PLR remained an independent prognostic factor for both OS and PFS in multivariate analysis (HR 1.60, 95%CI 1.6-2.40, p = 0.020; HR 1.99, 95%CI 1.11-3.49, p = 0.021). Systemic inflammation measured by NLR and PLR is an independent negative prognostic factor in HCC patients undergoing ICI therapy. Further studies are required to understand the biological mechanisms underlying this association and to investigate the predictive significance of circulating inflammatory biomarkers in HCC patients treated with ICIs.

Construction of a ceRNA network in hepatocellular carcinoma and comprehensive analysis of immune infiltration patterns

BACKGROUND

Hepatocellular carcinoma (HCC) is a type of refractory malignant tumor with high fatality rate. Currently, immunotherapy and competitive endogenous RNA (ceRNA) are research hotspots in HCC, but the relationship between ceRNA and the immune microenvironment in HCC is unclear.

METHODS

Firstly, a differentially expressed circRNA-miRNA-mRNA network was constructed from the GEO database, and functional enrichment analysis was performed. Next, combine the TCGA database to construct a ceRNA prognosis-related subnetwork. Establish a risk prediction model based on the mRNA in the sub-network, and evaluate the impact of the model on the prognosis. Use clinical samples to verify the expression of genes in the model. Finally, we analyzed the distribution of tumor infiltrating immune cells (TIC) in HCC, and explored the correlation between mRNAs in the ceRNA sub-network and immune infiltration.

RESULTS

We used the HCC ceRNA network (including 12 circRNA, 5 miRNA, and 8 mRNA) as a starting point for the identification of target genes (PSMD10, ESR1 and PPARGC1A) in the ceRNA prognosis-related subnetwork to establish a risk prediction model and elucidated its important role in predicting the poor prognosis of HCC. The differences in mRNA expression verified by clinical samples are consistent with the database. In addition, we found that the mRNAs in the ceRNA prognosis subnetwork are closely related to different types of TICs and immune checkpoints.

CONCLUSIONS

This study is expected to serve as a reference for the study of mechanisms underlying liver cancer, the screening of prognostic markers and the evaluation of the immune response.

Programmed Cell Death 1 and Hepatocellular Carcinoma: An Epochal Story

In recent years, immune-based therapies have emerged as novel pillars for hepatocellular carcinoma (HCC). The rationale of immune-checkpoint inhibitors (ICIs) trial in HCC originated from the fact that the tumor cells and the infiltrating stromal and immune cells promote an immunosuppressive tumor microenvironment, including the up-regulation of immune checkpoint molecules on their surface. Antibody-based blockage targeting inhibitory checkpoint molecules on cytotoxic T cells, including programmed cell death-1 (PD-1) or its counterpart on antigen-presenting cells has shown strong anti-tumor activity in a subset of HCC patients. Single nucleotide polymorphisms (SNP) of PD-1 gene may affect the PD-1 expression or function, which eventually can cause dysfunctionality of immune balance. Based on the inhibitory role of PD-1 in anti-tumor responses, it has been investigated in several studies as a candidate to test for genetic susceptibility of individuals to HCC. The present paper highlights the knowledge on cross-talks for liver immunology and HCC course, recent studies investigating the role of functional SNPs of PD-1 gene in Turkish HCC population, and the data on already investigated PD-1 inhibitor molecules in clinical trials.

Antibiotic Therapy is Associated with Worse Outcome in Patients with Hepatocellular Carcinoma Treated with Sorafenib

Background

Antibiotic treatment (ABT) affects the outcome of cancer patients treated with immune checkpoint inhibitors (ICIs) and chemotherapy, possibly by altering the gut microbiome. We investigated the impact of ABT on overall survival (OS) and progression-free survival (PFS) in patients with advanced HCC treated with sorafenib.

Methods

HCC patients treated with sorafenib between 05/2006 and 03/2020 at the Medical University of Vienna were retrospectively analyzed. ABT was defined as antibiotic use within 30 days prior to or after sorafenib initiation.

Results

Of 206 patients, the majority was male (n=171, 83%) with a mean age of 66±9.6 years. Half of patients (n=94, 46%) had impaired liver function (Child-Pugh stage B). Median time of follow-up was 10.8 (95% CI: 9.2-12.3) months. ABT was administered in 23 (11%) patients due to different types of proven or clinically suspected bacterial infections (n=17, 74%) and hepatic encephalopathy (n=6, 26%). The median duration of ABT was 14 (IQR: 12-30) days. Penicillin (n=13, 57%), followed by rifaximin (n=6, 26%), fluoroquinolones (n=3, 13%), and cephalosporins (n=1, 4%), was administered in the ABT group. The ABT group had a significantly shorter median OS (4.7 (95% CI: 3.2-6.1) months vs 11.4 (95% CI: 9.9-12.9) months, p=0.012), which was confirmed in multivariable analysis (HR: 1.91 (95% CI: 1.1-3.2), p=0.014). Similarly, PFS trended to be shorter in the ABT group (3.5 (95% CI: 1.6-5.4) months vs 4.8 (95% CI: 3.9-5.7) months, p=0.099). None of the 10 patients with complete or partial response was found in the ABT group.

Conclusion

ABT was independently associated with worse outcomes in sorafenib-treated HCC patients. Prospective studies are needed to elucidate the underlying mechanism.

REXO4 acts as a biomarker and promotes hepatocellular carcinoma progression

BACKGROUND

Hepatocellular carcinoma (HCC) is a leading cause of global cancer-related mortality and the most common form of liver cancer. REXO4 (RNA exonuclease 4 homolog) downregulation has previously been linked to enhanced chemosensitivity in breast cancer cells. The present study sought to comprehensively clarify the functional role of REXO4 in HCC.

METHODS

REXO4 expression levels in HCC tumor tissues and control tissue samples were established by analyzing data from the Gene Expression Omnibus (GEO) database. The expression of REXO4 was then knocked down in HCC cell lines to explore its functional role in these cells, while a gene set enrichment analysis (GSEA) approach was used to assess the functional regulator network associated with REXO4, and the Cell type Identification By Estimating Relative Subsets Of RNA Transcripts (CIBERSORT) algorithm was used to determine the relationship between this gene and immune cell infiltration of tumor tissues. The relationship between REXO4 and metabolic pathway was analyzed by oil red O staining. Cell Counting Kit-8 assays, colony formation, wound-healing assay, and a nude mouse subcutaneous tumor model were used to evaluate the function of REXO4 in HCC.

RESULTS

REXO4 was highly upregulated in HCC tumors and cell lines, and was an effective predictor of HCC patient prognosis. The results indicated that the knockdown of REXO4 inhibited the proliferation and progression of HCC in vitro and in vivo. GSEA approaches also revealed REXO4 to be associated with tumor progression. Furthermore, REXO4 was associated with the degree of increase of intratumoral immune cell infiltration in HCC tissues and cells, and this gene was also linked with altered lipid metabolism in HCC cells.

CONCLUSIONS

In summary, these analyses revealed REXO4 to be upregulated in HCC and to be associated with poor patient prognosis. In addition, this gene was closely linked to key cancer hallmark pathways and was revealed to play an important role in the susceptibility of liver tumors to immune cell infiltration and activation. Thus, targeting REXO4 may be a promising approach to treating patients with HCC in the near future.

ZnS@BSA Nanoclusters Potentiate Efficacy of Cancer Immunotherapy

Although immunotherapy such as immune checkpoint inhibitors has shown promising efficacy in cancer treatment, the responsiveness among patients is relatively limited. Activation of the cyclic guanosine monophosphate-adenosine monophosphate synthase/interferon gene stimulator (cGAS/STING) signaling pathway to upregulate innate immunity has become an emerging strategy for enhancing tumor immunotherapy. Herein, ZnS@BSA (bovine serum albumin) nanoclusters synthesized via a self-assembly approach are reported, where the released zinc ions under acidic tumor microenvironment significantly enhance cGAS/STING signals. Meanwhile, intracellular zinc ions can produce reactive oxygen species, which is further facilitated by the generated H₂ S gas from ZnS@BSA via specifically inhibiting catalase in hepatocellular carcinoma cells. It is found that the nanoclusters activate the cGAS/STING signals in mice, which promotes the infiltration of CD8⁺ T cells at the tumor site and cross-presentation of dendritic cells, leading to an improved immunotherapy efficacy against hepatocellular carcinoma.

CPI-203 improves the efficacy of anti-PD-1 therapy by inhibiting the induced PD-L1 overexpression in liver cancer

Hepatocellular carcinoma (HCC) is one of the commonest lethal malignancies worldwide, and often diagnosed at an advanced stage, without any curative therapy. Immune checkpoint blockers targeting the programmed death receptor 1 (PD‐1) have shown impressive antitumor activity in patients with advanced‐stage HCC, while the response rate is only 30%. Inducible PD‐L1 overexpression may result in a lack of response to cancer immunotherapy, which is attributed to a mechanism of adaptive immune resistance. Our study investigated that the overexpression of PD‐L1 promoted the invasion and migration of liver cancer cells in vitro, and the induced overexpression of PD‐L1 in the tumor microenvironment could weaken the effects of anti‐PD‐1 immunotherapy in a BALB/c mouse model of liver cancer. CPI‐203, a small‐molecule bromodomain‐containing protein 4 (BRD4) inhibitor, which can potently inhibit PD‐L1 expression in vitro and in vivo, combined with PD‐1 antibody improved the response to immunotherapy in a liver cancer model. Cell transfection and chromatin immunoprecipitation assay manifested that BRD4 plays a key role in PD‐L1 expression; CPI‐203 can inhibit PD‐L1 expression by inhibiting the BRD4 occupation of the PD‐L1 promoter region. This study indicates a potential clinical immunotherapy method to reduce the incidence of clinical resistance to immunotherapy in patients with HCC.

Immune Checkpoint Inhibitors in Hepatocellular Carcinoma: Current Progresses and Challenges

Hepatocellular carcinoma (HCC) is one of the most common malignant tumor in the world and its incidence is increasing in many countries. In recent years, with the deepening understanding of the immune and pathological mechanisms of HCC, immunotherapy based on the regulation of tumor immune microenvironment has become a new treatment choice for patients with HCC. Immune checkpoint inhibitors (ICIs) targeting programmed death protein-1, programmed death protein-ligand-1, or cytotoxic T-lymphocyte-associated antigen 4 are the most widely used. Instead of general immune-enhancing therapies, ICIs can reactivate anti-tumor immune responses by disrupting co-inhibitory T cell signaling. In this review, the research progress and existing problems of ICIs in the treatment of HCC in recent years are reviewed.

Thermal ablation and immunotherapy for hepatocellular carcinoma: Recent advances and future directions

Hepatocellular carcinoma (HCC) is one of most common cancers that cause death in the world. Thermal ablation (TA) is an important alternative treatment method for HCC patients who are not appropriate for surgery or liver transplantation. Particularly for small and early HCCs, TA can be considered as the first-line curative treatment. However, local and distant recurrence rates are still high even though the TA equipment and technology develop rapidly. Immunotherapy is a novel systemic treatment method to enhance the anti-tumor immune response of HCC patients, which has the potential to reduce the tumor recurrence and metastasis. The combination of local TA and systemic immunotherapy for HCCs may be an ideal treatment for enhancing the efficacy of TA and controlling the recurrence. Herein we summarize the latest progress in TA, immunotherapy, and their combination for the treatment of patients with HCC and discuss the limitations and future research directions of the combined therapy.

Relationships Between Indices of Tumor Aggressiveness in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) aggressiveness factors include serum levels of alpha-fetoprotein (AFP), maximum tumor diameter (MTD), tumor multifocality, and presence of portal vein thrombosis (PVT).

AIMS

The interdependence of these factors has not been closely studied.

METHODS

A large HCC database was examined for the presence of patients with PVT and multifocality and was analyzed retrospectively for the relationship of these 2 parameters to each other and to MTD and survival.

RESULTS

Multifocality was found to increase with increase in MTD in the whole cohort and especially in patients with PVT. PVT also increased with increasing MTD. Neither increases in multifocality nor in PVT depended on elevated serum AFP levels, although they each increased with higher AFP levels. PVT increased in monofocal tumors as MTD increased but increased further in multifocal tumors.

CONCLUSIONS

Multifocality and PVT appear to be separate processes, each increasing with increase in MTD and AFP levels. The data support the hypothesis that in hepatocarcinogenesis, various factors cause increase in MTD, that in turn causes increased multifocality and PVT, which are non-co-dependent. However, both multifocality and PVT mechanisms involve both HCC cell growth and invasiveness, multifocality in liver parenchyma, and PVT in the portal vein.

Immunological Markers, Prognostic Factors and Challenges Following Curative Treatments for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortalities worldwide. Patients with early-stage HCC are eligible for curative treatments, such as surgical resection, liver transplantation (LT) and percutaneous ablation. Although curative treatments provide excellent long-term survival, almost 70-80% of patients experience HCC recurrence after curative treatments. Tumor-related factors, including tumor size, number and differentiation, and underlying liver disease, are well-known risk factors for recurrence following curative therapies. Moreover, the tumor microenvironment (TME) also plays a key role in the recurrence of HCC. Many immunosuppressive mechanisms, such as an increase in regulatory T cells and myeloid-derived suppressor cells with a decrease in cytotoxic T cells, are implicated in HCC recurrence. These suppressive TMEs are also modulated by several factors and pathways, including mammalian target of rapamycin signaling, vascular endothelial growth factor, programmed cell death protein 1 and its ligand 1. Based on these mechanisms and the promising results of immune checkpoint blockers (ICBs) in advanced HCC, there have been several ongoing adjuvant studies using a single or combination of ICB following curative treatments in HCC. In this review, we strive to provide biologic and immunological markers, prognostic factors, and challenges associated with clinical outcomes after curative treatments, including resection, LT and ablation.

Potential predictors for survival in hepatocellular carcinoma patients treated with immune checkpoint inhibitors: A meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICI) are increasingly used in hepatocellular carcinoma (HCC) trials. However, the correlations between early endpoints, such as progression free survival (PFS), objective response rate (ORR), and disease control rate (DCR), and overall survival (OS) are unclear. In this study, the correlations between OS and other early endpoints were evaluated in HCC patients who received ICI.

METHODS

Pubmed and Embase were searched to October 2020. Clinical studies evaluating efficacy and outcomes of HCC patients treated with ICI were included. ORR, DCR, PFS and OS were extracted from individual studies. The Spearman's rank correlation coefficient and linear regression model were used to assess the correlation.

RESULTS

74 studies involving 9001 HCC cases were included. For HCC patients treated with ICI, the pooled ORR and DCR were 16% (95% CI: 14-18%) and 52% (95% CI: 47-57%), and the median PFS and OS were 3.75 (95% CI: 2.88-4.90) months, and 13.20 (95% CI: 11.88-14.82) months, retrospectively. The correlation between ORR, DCR, PFS and OS were 0.35 (R² = 0.21, p < 0.05), 0.43 (R² = 0.18, p < 0.05), and 0.50 (R² = 0.33, p < 0.05), respectively. Further, the association between PFS and OS of the combination strategy showed a better correlation (rs = 0.79, R² = 0.75, p < 0.05).

CONCLUSION

These results suggest that PFS could be potential surrogates for OS, especially PFS for patients who treated with ICI combination regimen.

Regulation Network and Prognostic Significance of Aldo-Keto Reductase (AKR) Superfamily Genes in Hepatocellular Carcinoma

Purpose

The aldo-keto reductase (AKR) superfamily members have been proposed with multiple roles in various tumors. Here, a comprehensive analysis on the integral role of AKR genes was conducted to evaluate the expression profile, regulation network, and prognostic significance in hepatocellular carcinoma (HCC).

Materials and Methods

Transcriptome datasets of HCC were obtained from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus. Univariate and multivariate Cox regression analyses were used to build a novel risk score model, and then were further used to identify independent prognostic factors for overall survival (OS) of HCC. A prognostic nomogram was developed and validated. The expression of these critical AKR members was also evaluated by quantitative real-time polymerase chain reaction and immunohistochemistry in HCC specimens.

Results

Eight differentially expressed AKR genes were identified in HCC. The dysregulation of most AKR genes was negatively correlated with DNA methylation, and a regulation network with transcription factors (TFs) was also established. Then, three critical AKR genes (AKR1B10, AKR1D1, and AKR7A3) were screened out to build a novel risk score model. Worse OS was observed in high-risk patients. Besides, a prognostic nomogram based on the model was further established and validated in both the TCGA and GSE14520 cohorts, which showed superior performance in predicting the OS of HCC patients. Notably, close correlations were identified between the risk score and tumor immune microenvironment, somatic mutation profiles, and drug susceptibilities of HCC. Finally, the upregulated AKR1B10 and downregulated AKR1D1 and AKR7A3 were further verified in HCC tumor and adjacent tissues from our institution.

Conclusion

The dysregulated AKR genes could be mediated by DNA methylation and TFs in HCC. The risk model established with superior prognostic performance further suggested the significant role of AKR genes involved in the progression of HCC.

Application of Immunotherapy in Hepatocellular Carcinoma

Hepatocellular carcinoma is one of the most common malignancies globally. It not only has a hidden onset but also progresses rapidly. Most HCC patients are already in the advanced stage of cancer when they are diagnosed, and have even lost the opportunity for surgical treatment. As an inflammation-related tumor, the immunosuppressive microenvironment of HCC can promote immune tolerance through a variety of mechanisms. Immunotherapy can activate tumor-specific immune responses, which brings a new hope for the treatment of HCC. At the present time, main immunotherapy strategies of HCC include immune checkpoint inhibitors, tumor vaccines, adoptive cell therapy, and so on. This article reviews the application and research progress of immune checkpoint inhibitors, tumor vaccines, and adoptive cell therapy in the treatment of HCC.

PD-L1, TMB, and other potential predictors of response to immunotherapy for hepatocellular carcinoma: how can they assist drug clinical trials?

INTRODUCTION

Hepatocellular carcinoma (HCC) represents the sixth most commonly diagnosed malignancy worldwide, accounting for millions of deaths annually. Despite immune checkpoint inhibitors (ICIs) reported important results, only a minority of HCC patients benefit from these treatments, and the identification of predictive biomarkers of response still remains a highly unmet need.

AREAS COVERED

Herein, we provide a timely overview of available evidence on biochemical predictors of response to immunotherapy in advanced HCC patients; we speculate on how PD-L1, TMB, and other emerging biomarkers could assist drug clinical trials in the near future. A literature search was conducted in June 2021 using Pubmed/Medline, Cochrane library, and Scopus databases.

EXPERT OPINION

Reliable predictors of response to ICIs are of pivotal importance to allow a proper stratification and selection of HCC patients that could derive more benefit from immunotherapy. Well-designed, multicenter clinical trials specifically focused on predictive biomarkers are warranted in this setting, where most of evidence currently derives from retrospective, single-center studies with small sample size.

Genetic Heterogeneity, Therapeutic Hurdle Confronting Sorafenib and Immune Checkpoint Inhibitors in Hepatocellular Carcinoma

Despite the latest advances in hepatocellular carcinoma (HCC) screening and treatment modalities, HCC is still representing a global burden. Most HCC patients present at later stages to an extent that conventional curative options are ineffective. Hence, systemic therapy represented by the tyrosine kinase inhibitor, sorafenib, in the first-line setting is the main treatment modality for advanced-stage HCC. However, in the two groundbreaking phase III clinical trials, the SHARP and Asia-Pacific trials, sorafenib has demonstrated a modest prolongation of overall survival in almost 30% of HCC patients. As HCC develops in an immune-rich milieu, particular attention has been placed on immune checkpoint inhibitors (ICIs) as a novel therapeutic modality for HCC. Yet, HCC therapy is hampered by the resistance to chemotherapeutic drugs and the subsequent tumor recurrence. HCC is characterized by substantial genomic heterogeneity that has an impact on cellular response to the applied therapy. And hence, this review aims at giving an insight into the therapeutic impact and the different mechanisms of resistance to sorafenib and ICIs as well as, discussing the genomic heterogeneity associated with such mechanisms.

CLEC4s as Potential Therapeutic Targets in Hepatocellular Carcinoma Microenvironment

Immunosuppressive tumor microenvironment in hepatocellular carcinoma (HCC) is critical in tumor development. C-type (Ca²⁺ -dependent) lectin (CLEC) receptors, essential in innate pattern recognition, have potential regulatory effects on immune cell trafficking and modulatory effects on cancer cell activity. However, information on the expression and prognostic value of CLECs in HCC is scanty. Herein, we explored the potential role of CLECs in HCC based on TCGA, ONCOMINE, GEPIA, UALCAN, cBioPortal, Metascape, TRRUST, and TIMER databases. Results demonstrated a significantly higher mRNA level of CLEC4A and CLEC4L in HCC tissues than normal liver tissues. Contrarily, we found significantly low CLEC4G/H1/H2/M expression in HCC tissues. The IHC analysis revealed the following: Absence of CLEC4A/J/K/M in normal and liver cancer tissues; high CLEC4C expression in HCC tissues; low expression and zero detection of CLEC4D/E/H1/H2/L in HCC tissues and normal tissues, respectively. And the HepG2 and LX-2 were used to verify the expression level of CLEC4s via qRT-PCR in vitro. Furthermore, the expression of CLEC4H1 (ASGR1) and CLEC4H2 (ASGR2) exhibited a significant relation to clinical stages. However, the expression of CLEC4A, CLEC4D, CLEC4E, CLEC4J (FCER2), CLEC4K (CD207), CLEC4G, CLEC4H1, CLEC4M, and CLEC4H2 decreased with tumor progression. Patients expressing higher CLEC4H1/H2 levels had longer overall survival than patients exhibiting lower expression. Moreover, CLEC4A/D/E/J/K/G/H1/M/H2 had significant down-regulated levels of promoter methylation. The expression level of CLEC4s was correlated with the infiltration of B cells, CD8 + T cells, CD4 + T cells, macrophage cells, neutrophil cells, and dendritic cells. Functional analysis revealed the potential role of CLECL4s in virus infection, including COVID-19. Also, hsa-miR-4278 and hsa-miR-324-5p, two potential miRNA targets of CLEC4s, were uncovered. This article demonstrates that CLEC4 is crucial for the development of HCC and is associated with infiltration of various immune cells, providing evidence for new immunotherapy targets in HCC.

Atezolizumab plus bevacizumab for unresectable or metastatic hepatocellular carcinoma

Introduction: The treatment of unresectable hepatocellular carcinoma (HCC) has radically changed after the approval of the combination of atezolizumab plus bevacizumab as first-line treatment. A strong preclinical rationale exists to support the combination of bevacizumab, an anti-vascular endothelial growth factor monoclonal antibody (mAb), and atezolizumab, an anti-programmed death ligand 1 mAb. The efficacy of the combination was first assessed in the phase Ib GO30140 study, and the combination was then proven superior to the prior standard of care, sorafenib, in the phase III IMbrave150 trial.Areas covered: This article focuses on the mechanism of action of atezolizumab and bevacizumab, their synergistic action, and the two clinical trials leading to approval. We also collected the body of post-hoc analyses and meta-analyses to help guide the decision-making process in terms of patient selection and subsequent treatments.Expert opinion: Atezolizumab plus bevacizumab are the current standard of care for first-line treatment of unresectable or metastatic HCC and treatment-naïve patient should be treated with the combination, unless contraindications to the drugs. Since all the available agents for further lines of treatment have been approved for sorafenib-pretreated patients, prospective trials, post-hoc analyses, and real-world data assessing valid treatment sequencing are strongly needed.

PD-1 Blockade for Hepatocellular Carcinoma: Current Research and Future Prospects

The treatment of hepatocellular carcinoma (HCC) has witnessed radical changes over the last few years, with the introduction of immune checkpoint inhibitors (ICI) in clinical practice, namely the combination of atezolizumab plus bevacizumab as the standard of care for first-line treatment of advanced HCC. The immunosuppressive microenvironment of the chronically inflamed liver makes HCC a fertile ground for the use of ICI. This review focuses on anti-programmed cell death-1 (PD-1) monoclonal antibodies (mAb), which have been extensively studied, as monotherapy, in combination with other ICI or with antiangiogenic agents. Currently, anti-PD-1 agents are approved by the United States Food and Drug Administration for second-line treatment in advanced HCC: nivolumab, alone or in combination with ipilimumab, and pembrolizumab. Lack of demonstration of survival benefit in first and second line led to the investigation of PD-1 agents in combination with multi-kinase inhibitors, with a number of first-line treatment regimens being actively investigated. Mounting evidence suggests a potential role of PD-1 blockade as adjuvant or neoadjuvant therapies. A key challenge remains the identification of biomarkers of response, since only a minority of patients appear to benefit from ICI.

IMbrave 151: a randomized phase II trial of atezolizumab combined with bevacizumab and chemotherapy in patients with advanced biliary tract cancer

Background:

Biliary tract cancers (BTCs) are heterogenous, highly aggressive tumors that harbor a dismal prognosis for which more effective treatments are needed. The role of cancer immunotherapy in BTC remains to be characterized. The tumor microenvironment (TME) of BTC is highly immunosuppressed and combination treatments are needed to promote effective anticancer immunity. Vascular endothelial growth factor (VEGF) drives immunosuppression in the TME by disrupting antigen presentation, limiting T-cell infiltration, or potentiating immune-suppressive cells. Many VEGF-regulated mechanisms are thought to be relevant to repressed antitumor immunity in BTC, making dual targeting of VEGF and programmed cell death protein 1 (PD-1)/PD-L1 pathways a rational approach. Gemcitabine and Cisplatin (Gem/Cis) can also modulate anticancer immunity through overlapping and complementary mechanisms to those regulated by VEGF. Anti-PD-L1/VEGF inhibition, coupled with chemotherapy, may potentiate antitumor immunity leading to enhanced clinical benefit.

Methods:

IMbrave 151 is a randomized, double-blind, placebo-controlled, multicenter, international phase II study to evaluate atezolizumab (a PD-L1 inhibitor) in combination with chemotherapy (gemcitabine and cisplatin) and bevacizumab (an anti-VEGF monoclonal antibody) as a first-line treatment for advanced BTC. Approximately 150 patients with previously untreated, advanced BTC will be randomized to either Arm A (atezolizumab + bevacizumab + Gem/Cis) or Arm B (atezolizumab + placebo + Gem/Cis). Randomization is stratified by the presence of metastatic disease, primary tumor location, and geographic region. The primary efficacy endpoint is investigator-assessed progression-free survival (PFS) per RECIST 1.1. Secondary endpoints include objective response rate (ORR), duration of response (DoR), disease control rate (DCR), overall survival (OS), and safety and patient reported outcomes (PROs). Tissue, blood, and stool samples will be collected at baseline and on-treatment in order to perform correlative biomarker analyses.

Discussion:

IMbrave 151 represents the first randomized study to evaluate combined PD-L1/VEGF blockade on a chemotherapy backbone in BTC.

Trial registration:

NCT identifier: NCT04677504; EUDRACT number: 2020-003759-14

Reductions in AFP and PIVKA-II can predict the efficiency of anti-PD-1 immunotherapy in HCC patients

BACKGROUND

Few biomarkers can predict the efficiency of PD-1 blockade in patients with hepatocellular carcinoma (HCC). This study aimed to investigate the prognostic role of AFP and PIVKA-II in HCC patients receiving anti-PD-1 immunotherapy.

METHODS

A total of 235 HCC patients treated with PD-1 blockade were enrolled. Serum AFP and PIVKA-II levels were collected before and after treatments. The patients were divided into groups based on the reduction in AFP and PIVKA-II: AFP reduction ≤50% vs AFP reduction > 50% and PIVKA-II reduction ≤50% vs PIVKA-II reduction > 50%. The primary endpoints included objective response rate (ORR), progression-free survival (PFS) and overall survival (OS). Binary logistic regression analyses were used to explore the related factors of ORR. A Cox proportional hazards model was employed to identify the potential prognostic factors of PFS and OS.

RESULTS

Among all the patients, 34.9% (82/235) achieved a complete or partial response. There was a positive correlation between AFP reduction > 50% or PIVKA-II reduction> 50% and the ORR of PD-1 blockade (P < 0.001 and = 0.003). PFS was significantly improved in patients with AFP reduction > 50% and PIVKA-II reduction > 50% (p < 0.001 and = 0.021). In addition, AFP reduction > 50% and PIVKA-II reduction> 50% were positively correlated with longer OS (p = 0.003 and 0.006).

CONCLUSION

Early reductions in AFP and PIVKA-II can be predictors of the efficacy of PD-1 blockade in HCC patients.

Cabozantinib in Advanced Hepatocellular Carcinoma: Efficacy and Safety Data from an International Multicenter Real-Life Cohort

BACKGROUND AND AIMS

The multikinase inhibitor cabozantinib has been approved for hepatocellular carcinoma (HCC) previously treated with sorafenib. We report safety and efficacy data of an international, multicenter, real-life cohort of patients with advanced HCC treated with cabozantinib.

METHODS

Patients with HCC who were treated with cabozantinib were retrospectively identified across 11 centers in Austria, Switzerland, and Germany. Patients' characteristics, adverse events, duration of treatment and overall survival (OS) data were analyzed until April 1, 2020.

RESULTS

Eighty-eight patients from 11 centers were included. The predominant underlying liver diseases were NAFLD/NASH in 26 (30%) and hepatitis C infection in 21 (24%) patients. Seventy-eight patients (89%) were classified as Barcelona clinic liver cancer (BCLC) stage C. Sixty patients (68%) were Child-Pugh A, whereas 22 (25%) were Child-Pugh B, respectively. Cabozantinib was used as systemic second- and third-line or later treatment in 41 (47%) and 46 (52%) patients, respectively. The following best responses under cabozantinib were documented: partial response in 6 (7%), stable disease in 28 (32%), and progressive disease in 28 (32%) patients, respectively. Fifty-two patients (59%) died during follow-up. The median OS from start of cabozantinib treatment was 7.0 months in the entire cohort and 9.7 months in Child-Pugh A patients, while Child-Pugh B patients had a median OS of 3.4 months, respectively. Thirty-seven (42%) patients fulfilled the CELESTIAL inclusion and exclusion criteria, showing a median OS of 11.1 months. Most common adverse events were fatigue (15.6%) and diarrhea (15.6%).

CONCLUSION

Cabozantinib treatment was effective, safe, and feasible in patients with advanced HCC in patients with compensated cirrhosis. Patients in the real-life setting had more advanced liver disease - in which 25% of patients were Child-Pugh B. However, OS in patients with Child-Pugh A cirrhosis was similar to that reported in the phase 3 trial (CELESTIAL).

The evolving treatment paradigm of advanced hepatocellular carcinoma: putting all the pieces back together

PURPOSE OF REVIEW

The therapeutic landscape of advanced hepatocellular carcinoma (HCC) has become notably complex in recent years. With this review, we aimed to put the most recent findings in perspective and tried to delineate the rapidly changing treatment algorithm.

RECENT FINDINGS

The combination of atezolizumab and bevacizumab has become the new first-line standard of care treatment for unresectable HCC after the positive results of the phase 3 IMbrave150 study. Nivolumab monotherapy failed to demonstrate advantage versus sorafenib in the CheckMate 459 trial, while two different therapeutic strategies (sintilimab and bevacizumab biosimilar and donafenib) outperformed sorafenib in two phase 2/3 studies conducted in the Chinese population. Several immunotherapy combinations are currently under study in large phase 3 trials after promising results in earlier phase studies. About further lines of treatment, the combination of ipilimumab and nivolumab was approved for sorafenib-pretreated patients after the positive results of the phase 1/2 CheckMate 040 study and apatinib was proven effective in the Chinese population in a phase 2/3 study, while pembrolizumab as monotherapy did not show statistically significant superiority when compared with placebo in the KEYNOTE-240 study.

SUMMARY

Because of the growing complexity of advanced HCC treatment, the implementation of predictive biomarkers of response is eagerly needed.

Lenvatinib plus pembrolizumab: the next frontier for the treatment of hepatocellular carcinoma?

Introduction: While sorafenib monotherapy represented the mainstay of medical treatment for advanced hepatocellular carcinoma (HCC) patients for more than a decade, novel agents and combination therapies have recently produced unprecedented paradigm shifts. The combination of lenvatinib plus pembrolizumab is now being evaluated as a front-line treatment in advanced HCC patients; early phase clinical trials have already reported promising results.Areas covered: This paper reviews the combination of lenvatinib plus pembrolizumab for the treatment of advanced HCC. The preclinical rationale and completed and ongoing trials are examined and later, the authors reflect on biomarkers of predictive of response to immune-based combinations and future treatment decision-making on the basis of tolerability and clinical benefits provided by these novel therapeutics. A literature search was conducted in April 2021 of Pubmed/Medline, Cochrane library and Scopus databases; moreover, abstracts of international cancer meetings were reviewed.Expert opinion: The landscape of new agents and combinations continues to expand. Recently, immune-based combinations have reported important results in advanced HCC, as witnessed by the landmark IMbrave150 trial. Based on the promising results of early phase clinical trials, lenvatinib plus pembrolizumab has the potential to represent a novel treatment option in this setting.

Cancer and hepatic steatosis

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent and increasing liver disease, which encompasses a variety of liver diseases of different severity. NAFLD can lead to liver cirrhosis with all its complications as well as hepatocellular carcinoma (HCC). Steatosis of the liver is not only related to obesity and other metabolic risk factors, but can also be caused by several drugs, including certain cytotoxic chemotherapeutic agents. In patients undergoing liver surgery, hepatic steatosis is associated with an increased risk of post-operative morbidity and mortality. This review paper summarizes implications of hepatic steatosis on the management of patients with cancer. Specifically, we discuss the epidemiological trends, pathophysiological mechanisms, and management of NAFLD, and its role as a leading cause of liver cancer. We elaborate on factors promoting immunosuppression in patients with NAFLD-related HCC and how this may affect the efficacy of immunotherapy. We also summarize the mechanisms and clinical course of chemotherapy-induced acute steatohepatitis (CASH) and its implications on cancer treatment, especially in patients undergoing liver resection.

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Non-alcoholic fatty liver disease can lead to cirrhosis with all its complications, including hepatocellular carcinoma.

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Chemotherapy-associated acute steatohepatitis is a side-effect of chemotherapeutic agents and may limit treatment options.

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In this review we summarize current clinical concepts of NAFLD and CASH that help clinicians in their clinical practice.

The multidisciplinary management of hepatocellular carcinoma with portal vein tumor thrombus

Portal vein tumor thrombus (PVTT) is one of the most common complications of hepatocellular carcinoma (HCC), which refers to the advanced stage of HCC and indicates an extremely poor prognosis. Monotherapy cannot effectively prolong the survival benefit of patients with HCC-PVTT characterized by a high recurrence rate. With great progress in the area of immune and molecular targeted therapy, there comes a promising era of multidisciplinary management of HCC. Survival benefits can be achieved based on accurate diagnosis, staging, and multidisciplinary management. Additionally, in terms of the presence of controversy about the standard treatment algorithm and the absence of universal treatment guidelines, a multidisciplinary management program may afford the best hope for HCC-PVTT patients via appropriate implement of various treatment protocols.

A novel therapeutic strategy for hepatocellular carcinoma: Immunomodulatory mechanisms of selenium and/or selenoproteins on a shift towards anti-cancer

Selenium (Se) is an essential trace chemical element that is widely distributed worldwide. Se exerts its immunomodulatory and nutritional activities in the human body in the form of selenoproteins. Se has increasingly appeared as a potential trace element associated with many human diseases, including hepatocellular carcinoma (HCC). Recently, increasing evidence has suggested that Se and selenoproteins exert their immunomodulatory effects on HCC by regulating the molecules of oxidative stress, inflammation, immune response, cell proliferation and growth, angiogenesis, signaling pathways, apoptosis, and other processes in vitro cell studies and in vivo animal studies. Se concentrations are generally low in tissues of patients with HCC, such as blood, serum, scalp hair, and toenail. However, Se concentrations were higher in HCC patient tissues after Se supplementation than before supplementation. This review summarizes the significant relationship between Se and HCC, and details the role of Se as a novel immunomodulatory or immunotherapeutic approach against HCC.

Targeting human Acyl-CoA:cholesterol acyltransferase as a dual viral and T cell metabolic checkpoint

Determining divergent metabolic requirements of T cells, and the viruses and tumours they fail to combat, could provide new therapeutic checkpoints. Inhibition of acyl-CoA:cholesterol acyltransferase (ACAT) has direct anti-carcinogenic activity. Here, we show that ACAT inhibition has antiviral activity against hepatitis B (HBV), as well as boosting protective anti-HBV and anti-hepatocellular carcinoma (HCC) T cells. ACAT inhibition reduces CD8+ T cell neutral lipid droplets and promotes lipid microdomains, enhancing TCR signalling and TCR-independent bioenergetics. Dysfunctional HBV- and HCC-specific T cells are rescued by ACAT inhibitors directly ex vivo from human liver and tumour tissue respectively, including tissue-resident responses. ACAT inhibition enhances in vitro responsiveness of HBV-specific CD8+ T cells to PD-1 blockade and increases the functional avidity of TCR-gene-modified T cells. Finally, ACAT regulates HBV particle genesis in vitro, with inhibitors reducing both virions and subviral particles. Thus, ACAT inhibition provides a paradigm of a metabolic checkpoint able to constrain tumours and viruses but rescue exhausted T cells, rendering it an attractive therapeutic target for the functional cure of HBV and HBV-related HCC.

Identification of novel targets of miR-622 in hepatocellular carcinoma reveals common regulation of cooperating genes and outlines the oncogenic role of zinc finger CCHC-type containing 11

The poor prognosis of advanced hepatocellular carcinoma (HCC) is driven by diverse features including dysregulated microRNAs inducing drug resistance and stemness. Lin-28 homolog A (LIN28A) and its partner zinc finger CCHC-type containing 11 (ZCCHC11) cooperate in binding, oligouridylation and subsequent degradation of tumorsuppressive let-7 precursor microRNAs. Functionally, activation of LIN28A was recently shown to promote stemness and chemoresistance in HCC. However, the expression and regulation of LIN28A in HCC had been unclear. Moreover, the expression, regulation and function of ZCCHC11 in liver cancer remained elusive. In contrast to "one-microRNA-one-target" interactions, we identified common binding sites for miR-622 in both LIN28A and ZCCHC11, suggesting miR-622 to function as a superior pathway regulator. Applying comprehensive microRNA database screening, human hepatocytes and HCC cell lines, patient-derived tissue samples as well as "The Cancer Genome Atlas" (TCGA) patient cohorts, we demonstrated that loss of tumorsuppressive miR-622 mediates derepression and overexpression of LIN28A in HCC. Moreover, the cooperator of LIN28A, ZCCHC11, was newly identified as a prognostic and therapeutic target of miR-622 in liver cancer. Together, identification of novel miR-622 target genes revealed common regulation of cooperating genes and outlines the previously unknown oncogenic role of ZCCHC11 in liver cancer.

Host Epigenetic Alterations and Hepatitis B Virus-Associated Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most frequent primary malignancy of the liver and a leading cause of cancer-related deaths worldwide. Although much progress has been made in HCC drug development in recent years, treatment options remain limited. The major cause of HCC is chronic hepatitis B virus (HBV) infection. Despite the existence of a vaccine, more than 250 million individuals are chronically infected by HBV. Current antiviral therapies can repress viral replication but to date there is no cure for chronic hepatitis B. Of note, inhibition of viral replication reduces but does not eliminate the risk of HCC development. HBV contributes to liver carcinogenesis by direct and indirect effects. This review summarizes the current knowledge of HBV-induced host epigenetic alterations and their association with HCC, with an emphasis on the interactions between HBV proteins and the host cell epigenetic machinery leading to modulation of gene expression.

Tumor Solid Stress: Assessment with MR Elastography under Compression of Patient-Derived Hepatocellular Carcinomas and Cholangiocarcinomas Xenografted in Mice

Malignant tumors have abnormal biomechanical characteristics, including high viscoelasticity, solid stress, and interstitial fluid pressure. Magnetic resonance (MR) elastography is increasingly used to non-invasively assess tissue viscoelasticity. However, solid stress and interstitial fluid pressure measurements are performed with invasive methods. We studied the feasibility and potential role of MR elastography at basal state and under controlled compression in assessing altered biomechanical features of malignant liver tumors. MR elastography was performed in mice with patient-derived, subcutaneously xenografted hepatocellular carcinomas or cholangiocarcinomas to measure the basal viscoelasticity and the compression stiffening rate, which corresponds to the slope of elasticity versus applied compression. MR elastography measurements were correlated with invasive pressure measurements and digital histological readings. Significant differences in MR elastography parameters, pressure, and histological measurements were observed between tumor models. In multivariate analysis, collagen content and interstitial fluid pressure were determinants of basal viscoelasticity, whereas solid stress, in addition to collagen content, cellularity, and tumor type, was an independent determinant of compression stiffening rate. Compression stiffening rate had high AUC (0.87 ± 0.08) for determining elevated solid stress, whereas basal elasticity had high AUC for tumor collagen content (AUC: 0.86 ± 0.08). Our results suggest that MR elastography compression stiffening rate, in contrast to basal viscoelasticity, is a potential marker of solid stress in malignant liver tumors.

Atezolizumab in advanced hepatocellular carcinoma: good things come to those who wait

Advanced hepatocellular carcinoma (HCC) patients present poor prognosis. However, recent years have seen the advent of several novel treatments in this setting, where the role of immune checkpoint inhibitors has been investigated. Among these, the PD-L1 inhibitor atezolizumab in combination with bevacizumab has reported unprecedented results in treatment-naive patients with unresectable disease, with the recently published IMbrave150 Phase III trial showing the superiority of the combination over sorafenib monotherapy, and after having attended more than a decade of 'stagnation', the HCC medical community has a new standard of care. Herein, we examine the development and the impact of atezolizumab in advanced HCC, summarizing the mechanism of action, pharmacokinetics and recent evidence from Phase I to III clinical trials.

Macrophages in Chronic Liver Failure: Diversity, Plasticity and Therapeutic Targeting

Chronic liver injury results in immune-driven progressive fibrosis, with risk of cirrhosis development and impact on morbidity and mortality. Persistent liver cell damage and death causes immune cell activation and inflammation. Patients with advanced cirrhosis additionally experience pathological bacterial translocation, exposure to microbial products and chronic engagement of the immune system. Bacterial infections have a high incidence in cirrhosis, with spontaneous bacterial peritonitis being the most common, while the subsequent systemic inflammation, organ failure and immune dysregulation increase the mortality risk. Tissue-resident and recruited macrophages play a central part in the development of inflammation and fibrosis progression. In the liver, adipose tissue, peritoneum and intestines, diverse macrophage populations exhibit great phenotypic and functional plasticity determined by their ontogeny, epigenetic programming and local microenvironment. These changes can, at different times, promote or ameliorate disease states and therefore represent potential targets for macrophage-directed therapies. In this review, we discuss the evidence for macrophage phenotypic and functional alterations in tissue compartments during the development and progression of chronic liver failure in different aetiologies and highlight the potential of macrophage modulation as a therapeutic strategy for liver disease.

The Role of Cabozantinib as a Therapeutic Option for Hepatocellular Carcinoma: Current Landscape and Future Challenges

The systemic treatment of advanced hepatocellular carcinoma (HCC) has significantly changed over the last years, with the introduction of two new standard-of-care first-line treatments (lenvatinib and the combination of atezolizumab and bevacizumab) and the success of several new agents in second line. In particular, after the approval of regorafenib, ramucirumab and cabozantinib, the landscape of second-line treatment has become notably complex, providing a serious challenge in clinical practice. In this review, we focus on cabozantinib, a multikinase inhibitor which was proven effective in improving overall and progression-free survival of patients previously treated with sorafenib in the randomized Phase III CELESTIAL trial. CELESTIAL is the only phase III study to have included patients in the third-line setting and cabozantinib efficacy was confirmed in several post hoc analyses, irrespective of alpha-fetoprotein levels, albumin-bilirubin score, age, and duration of previous sorafenib treatment. The safety profile of cabozantinib in the CELESTIAL trial was comparable with other multikinase inhibitors used for HCC and the most frequent grade ≥3 adverse events were diarrhea, palmar-plantar erythrodysesthesia, fatigue, hypertension, and aspartate aminotransferase increase. Tolerability did not differ between younger and older patients and quality of life was significantly improved compared to placebo during the treatment. In this review, we also make a particular mention to the use of cabozantinib in populations which are normally excluded from clinical trials, such as older patients and Child-Pugh B patients. Finally, we present the new treatment strategies in which cabozantinib is being tested, most notably the combination of cabozantinib and atezolizumab in the first-line setting in the phase III COSMIC-312 trial and the use of cabozantinib after progression on immune-checkpoint inhibitors.

A new perspective on the immune escape mechanism in HCC: onco-foetal reprogramming

We found a shared immunosuppressive microenvironment between foetal liver and hepatocellular carcinoma (HCC) which includes the re-emergence of foetal-associated endothelial cells (PLVAP/VEGFR2) and foetal-like (FOLR2) tumour-associated macrophages in HCC, mediated via VEGF-NOTCH signalling. The discoveries suggest possible novel targets for therapeutic interventions in HCC.

DNA primase subunit 1 deteriorated progression of hepatocellular carcinoma by activating AKT/mTOR signaling and UBE2C-mediated P53 ubiquitination

Background

DNA primase subunit 1 (PRIM1) has been reported as a novel oncogene in several cancer types. However, its roles in hepatocellular carcinoma (HCC) remain unclear. This study aimed to investigate underlying mechanisms of PRIM1 and identify it as a potential molecular target for HCC.

Methods

Hub genes were screened between HCC tissues and normal liver tissues in 3 gene expression omnibus (GEO) datasets and the cancer genome atlas (TCGA). The expression features and prognostic value of one of the hub genes PRIM1 were analyzed by bioinformatic analyses and immunohistochemistry. Loss-of-function and gain-of-function studies were used to investigate the regulatory role of PRIM1 in HCC cells. Real-time (RT)-qPCR, western blotting, and ubiquitin immunoprecipitation assays were performed to explore the underlying mechanisms. The xenograft model was employed to detect the roles of PRIM1 in tumor growth in vivo. Finally, the 3D spheroid model was conducted to validate the role of PRIM1 in tumor growth and sorafenib resistance.

Results

The hub genes of HCC were screened in multiple bioinformatic datasets. PRIM1, as one of the hub genes, was significantly overexpressed in HCC tissues in mRNA and protein levels. In addition, high expression of PRIM1 indicated poor prognosis of HCC patients in TCGA, ICGC, and Nantong cohorts. Overexpression of PRIM1 promoted the proliferation, migration/invasion, and sorafenib resistance of HCC cells, with the decrease in apoptosis and cell cycle arrest. Mechanically, PRIM1 facilitated epithelial-mesenchymal transition (EMT) process and the activity of PI3K/AKT/mTOR signaling of HCC cells. Additionally, PRIM1 could cause the ubiquitination and degradation of P53 by upregulating Ubiquitin Conjugating Enzyme E2 C (UBE2C). Furthermore, knockdown of PRIM1 significantly inhibited the growth of xenograft tumors and HCC cells-derived spheroids with enhanced sorafenib resistance.

Conclusion

This study implies that PRIM1 may play a key role in the progression of HCC and may serve as a potential target for HCC treatment.

Inflammatory Mechanisms Underlying Nonalcoholic Steatohepatitis and the Transition to Hepatocellular Carcinoma

Nonalcoholic fatty liver disease (NAFLD) is a rising chronic liver disease and comprises a spectrum from simple steatosis to nonalcoholic steatohepatitis (NASH) to end-stage cirrhosis and risk of hepatocellular carcinoma (HCC). The pathogenesis of NAFLD is multifactorial, but inflammation is considered the key element of disease progression. The liver harbors an abundance of resident immune cells, that in concert with recruited immune cells, orchestrate steatohepatitis. While inflammatory processes drive fibrosis and disease progression in NASH, fueling the ground for HCC development, immunity also exerts antitumor activities. Furthermore, immunotherapy is a promising new treatment of HCC, warranting a more detailed understanding of inflammatory mechanisms underlying the progression of NASH and transition to HCC. Novel methodologies such as single-cell sequencing, genetic fate mapping, and intravital microscopy have unraveled complex mechanisms behind immune-mediated liver injury. In this review, we highlight some of the emerging paradigms, including macrophage heterogeneity, contributions of nonclassical immune cells, the role of the adaptive immune system, interorgan crosstalk with adipose tissue and gut microbiota. Furthermore, we summarize recent advances in preclinical and clinical studies aimed at modulating the inflammatory cascade and discuss how these novel therapeutic avenues may help in preventing or combating NAFLD-associated HCC.

Response Stratification in the First-Line Combined Immunotherapy of Hepatocellular Carcinoma at Genomic, Transcriptional and Immune Repertoire Levels

BACKGROUND

Immunotherapy combined with VEGF inhibitor has become the new first-line therapy for advanced or metastatic hepatocellular carcinoma (HCC). However, the biomarkers for response and prognosis stratification of HCC first-line combined immunotherapy have not been clarified.

METHODS

Here, we obtained the genomic alteration data from pre-therapeutic samples of 103 HCC patients using a 605-gene NGS test, and obtained the transcriptional and T cell receptor (TCR) diversity data from 18 patients who underwent the first-line combined immunotherapy using RNAseq and TCR sequencing, respectively. Patients received sorafenib/sintilimab or lenvatinib/sintilimab combined first-line therapy and the response was assessed at 3-6 cycles of therapy.

RESULTS

No stratification of response was found in high-frequency key driver gene mutations, including TP53 and TERT. However, significantly higher ratio of progression (PD) was found in patients carrying MDM4 amplification. Similarly, FGF/3/4/19 amplifications could also result in high ratio of PD. The mRNA and lncRNA levels of eight genes related to hepatic metabolism and immune microenvironment exhibited significant differences between PR/SD and PD group, including DGKI, TNFSF14, CHST4, ACTIN1, PFKP, SLC51B, LCK and ERN1, suggesting stratification of response. Furthermore, moderate correlation was identified between the stratification genes (CHST4, SLC51B and ERN1) and immune factors (TIGIT, CD34, ICAM1, CCL5, CXCL9 and CXCL10), suggesting potential roles of these factors in immunoregulation. Strong linear correlation was found between any two of the three indexes for TCR CDR3 diversity, including Shannon-Wiener Index, Simpson index and evenness. However, no significant difference was found in the three indexes between the PR/SD and PD group, suggesting no stratification of response by these indexes.

CONCLUSION

We identified several potential biomarkers for response stratification in the first-line combined immunotherapy. MDM4 was capable of predicting disease progression, and a panel mRNA and lncRNA of eight genes may also predict the response. Further validation is needed to verify these biomarkers.

LncRNA EPIC1 promotes tumor angiogenesis via activating the Ang2/Tie2 axis in non-small cell lung cancer

AIMS

Non-small cell lung cancer (NSCLC) is considered a highly fatal tumor. Importantly, angiogenesis is critical for tumor progression. Long non-coding RNAs (lncRNAs), which are untranslatable, control cell functions through different pathways. lncRNA EPIC1 has been reported to promote cell viability, cell cycle progression, and invasion. However, the relationship between EPIC1 and tumor angiogenesis remains an enigma. We explored the role of EPIC1 in tumor angiogenesis in NSCLC.

MATERIALS AND METHODS

First, EPIC1 expression was analyzed using the GEPIA database and was further verified using qPCR in tumor tissues from patients with NSCLC and NSCLC cell lines. Next, EPIC1 function was detected using loss-of-function and gain-of-function assays. Moreover, EdU staining, flow cytometry, and channel formation assays were performed to assess HUVEC proliferation and channel the formation in the NSCLC-HUVEC transwell co-culture system.

KEY FINDINGS

EPIC1 expression was significantly upregulated in NSCLC tissues and cell lines. Furthermore, the overexpression of EPIC1 in NSCLC cells stimulated HUVEC channel formation and proliferation by activating Ang2/Tie2 signaling, and the opposite results were obtained when EPIC1 was silenced in NSCLC cells. The density of new blood vessels was simultaneously increased by EPIC1 overexpression in vivo, using CAM angiogenesis model and a nude mouse tumor model. Finally, all these experimental findings could be established in the samples from patients with NSCLC. We postulate that EPIC1 promotes tumor angiogenesis by activating the Ang2/Tie2 axis in NSCLC.

SIGNIFICANCE

Elucidating the molecular and cellular mechanisms of EPIC1 in tumor angiogenesis provides a novel perspective on NSCLC clinical therapy.

Risk Factors, Pathogenesis, and Strategies for Hepatocellular Carcinoma Prevention: Emphasis on Secondary Prevention and Its Translational Challenges

Hepatocellular carcinoma (HCC) is a leading cause of cancer-associated mortality globally. Given the limited therapeutic efficacy in advanced HCC, prevention of HCC carcinogenesis could serve as an effective strategy. Patients with chronic fibrosis due to viral or metabolic etiologies are at a high risk of developing HCC. Primary prevention seeks to eliminate cancer predisposing risk factors while tertiary prevention aims to prevent HCC recurrence. Secondary prevention targets patients with baseline chronic liver disease. Various epidemiological and experimental studies have identified candidates for secondary prevention-both etiology-specific and generic prevention strategies-including statins, aspirin, and anti-diabetic drugs. The introduction of multi-cell based omics analysis along with better characterization of the hepatic microenvironment will further facilitate the identification of targets for prevention. In this review, we will summarize HCC risk factors, pathogenesis, and discuss strategies of HCC prevention. We will focus on secondary prevention and also discuss current challenges in translating experimental work into clinical practice.