Tremelimumab in combination with ablation in patients with advanced hepatocellular carcinoma

Up to seven criteria in selection of systemic therapy for hepatocellular carcinoma

Barcelona clinic liver cancer (BCLC) intermediate stage hepatocellular carcinoma is a heterogenous disease. Transarterial chemoembolization is offered as the first line therapy in this disease stage. Recent advances in systemic therapy have markedly improved outcomes even in advanced stage disease. The use of systemic therapy in BCLC intermediate stage disease may now be of therapeutic benefit in selected patients. We will focus on "the up to seven" criteria and its utility in selecting systemic therapy.

Immune Checkpoint Inhibitors for Advanced Hepatocellular Carcinoma: Monotherapies and Combined Therapies

Hepatocellular carcinoma (HCC) is an important cause of cancer death and is considered the 3rd most lethal around the world. Hepatectomy, liver transplantation, and ablation therapy are considered curative treatments for early-stage HCC. Transarterial chemoembolization is the preferred therapy for intermediate stage HCC. Ssystemic therapy is recommended for advanced HCC. For more than a decade, sorafenib and lenvatinib were used as the first-line treatment for the advanced HCC. For the great success of immunotherapy in melanoma and lung cancer, some immune-based treatments, such as immune checkpoint inhibitors (ICIs), have been applied in the treatment of HCC. The anti-programmed cell death protein 1 (PD1) antibodies, including nivolumab and pembrolizumab, have been approved by the Food and Drug Administration for sorafenib-pretreated patients. Moreover, due to the results of durable antitumor responses attained from the phase 3 trials, atezolizumab in combination with bevacizumab is now the standard therapy for advanced HCC. Recently, there are a lot of clinical trials involving the ICIs, as monotherapy or combination therapy, with tyrosine kinase inhibitors, antiangiogenic drugs, cytotoxic agents, and locoregional treatments, providing a promising outcome for advanced HCC. Thus, this review summarized the role of ICIs for HCC patients with monotherapy or combination therapy. The success and failures of monotherapy and combination therapy involving ICIs have provided advanced insights into HCC treatment and led to novel avenues to improve therapy efficacy in HCC.

Integrated use of PD-1 inhibition and transarterial chemoembolization for hepatocellular carcinoma: evaluation of safety and efficacy in a retrospective, propensity score-matched study

Background

Immune checkpoint inhibitors (ICIs) have revolutionized treatment of advanced hepatocellular carcinoma. Integrated use of transarterial chemoembolization (TACE), a locoregional inducer of immunogenic cell death, with ICI has not been formally assessed for safety and efficacy outcomes.

Methods

From a retrospective multicenter dataset of 323 patients treated with ICI, we identified 31 patients who underwent >1 TACE 60 days before or concurrently, with nivolumab at a single center. We derived a propensity score-matched cohort of 104 patients based on Child-Pugh Score, portal vein thrombosis, extrahepatic metastasis and alpha fetoprotein (AFP) who received nivolumab monotherapy. We described overall survival (OS), progression-free survival (PFS), objective responses according to modified RECIST criteria and safety in the multimodal arm in comparison to monotherapy.

Results

Over a median follow-up of 9.3 (IQR 4.0–16.4) months, patients undergoing multimodal immunotherapy with TACE achieved a significantly longer median (95% CI) PFS of 8.8 (6.2–23.2) vs 3.7 (2.7–5.4) months (log-rank 0.15, p<0.01) in the monotherapy group. Multimodal immunotherapy with TACE demonstrated a numerically longer OS compared with ICI monotherapy with a median 35.1 (16.1–Not Evaluable) vs 16.6 (15.7–32.6) months (log-rank 0.41, p=0.12). In the multimodal treatment group, there were three (10%) grade 3 or higher adverse events (AEs) attributed to immunotherapy compared with seven (6.7%) in the matched ICI monotherapy arm. There were no AEs grade 3 or higher attributed to TACE in the multimodal treatment arm. At 3 months following each TACE in the multimodal arm, there was an overall objective response rate of 84%. There were no significant changes in liver functional reserve 1 month following each TACE. Four patients undergoing multimodal treatment were successfully bridged to transplant.

Conclusions

TACE can be safely integrated with programmed cell death 1 blockade and may lead to a significant delay in tumor progression and disease downstaging in selected patients.

Emerging immunotherapy for HCC: A guide for hepatologists

HCC is one of the most common cancers worldwide, and the third leading cause of cancer-related death globally. HCC comprises nearly 90% of all cases of primary liver cancer. Approximately half of all patients with HCC receive systemic therapy during their disease course, particularly in the advanced stages of disease. Immuno-oncology has been paradigm shifting for the treatment of human cancers, with strong and durable antitumor activity in a subset of patients across a variety of malignancies including HCC. Immune checkpoint inhibition with atezolizumab and bevacizumab, an antivascular endothelial growth factor neutralizing antibody, has become first-line therapy for patients with advanced HCC. Beyond immune checkpoint inhibition, immunotherapeutic strategies such as oncolytic viroimmunotherapy and adoptive T-cell transfer are currently under investigation. The tumor immune microenvironment of HCC has significant immunosuppressive elements that may affect response to immunotherapy. Major unmet challenges include defining the role of immunotherapy in earlier stages of HCC, evaluating combinatorial strategies that use targeting of the immune microenvironment plus immune checkpoint inhibition, and identifying treatment strategies for patients who do not respond to the currently available immunotherapies. Herein, we review the rationale, mechanistic basis and supporting preclinical evidence, and available clinical evidence for immunotherapies in HCC as well as ongoing clinical trials of immunotherapy.

Local and Regional Therapies for Hepatocellular Carcinoma and Future Combinations

Simple Summary

Percutaneous interventional radiological techniques offer many alternatives for treatment of Hepatocellular Carcinoma (HCC) using local anesthesia and sedation. These methods aim to destroy the malignant tumors locally without affecting the non-malignant liver. In this way, complications are kept low and patient recovery is quick. Indications depend on tumor size, type and stage, as well as patient’s condition, liver function and co-morbidities. In recent years, a lot of research has been made in combining such approaches with immune therapy, but there is still much work to be done. This manuscript tries to analyze where we stand today and explain, using a comprehensive algorithm, the treatment options for each different clinical condition.

Abstract

Background: Hepatocellular carcinoma (HCC) can be treated by local and regional methods of percutaneous interventional radiological techniques. Indications depend on tumor size, type and stage, as well as patient’s condition, liver function and co-morbidities. According to international classification systems such as Barcelona Clinic Liver Cancer (BCLC) classification, very early, early or intermediate staged tumors can be treated either with ablative methods or with transarterial chemoembolization (TACE), depending on tumor characteristics. The combination of both allows for individualized forms of treatment with the ultimate goal of improving response and survival. In recent years, a lot of research has been carried out in combining locoregional approaches with immune therapy. Although recent developments in systemic treatment, especially immunotherapy, seem quite promising and have expanded possible combined treatment options, there is still not enough evidence in their favor. The aim of this review is to provide a comprehensive up-to-date overview of all these techniques, explaining indications, contraindications, technical problems, outcomes, results and complications. Moreover, combinations of percutaneous treatment with each other or with immunotherapy and future options will be discussed. Use of all those methods as down-staging or bridging solutions until surgery or transplantation are taken into consideration will also be reviewed. Conclusion: Local and regional therapies remain a mainstay of curative and palliative treatment of patients with HCC. Currently, evidence on potential combination of the local and regional treatment options with each other as well as with other treatment modalities is growing and has the potential to further individualize HCC therapy. To identify the most suitable treatment option out of these new various options, a repeated interdisciplinary discussion of each case by the tumor board is of utmost importance.

Solute carrier family 2 members 1 and 2 as prognostic biomarkers in hepatocellular carcinoma associated with immune infiltration

BACKGROUND

Metabolic reprogramming has been identified as a core hallmark of cancer. Solute carrier family 2 is a major glucose carrier family. It consists of 14 members, and we mainly study solute carrier family 2 member 1 (SLC2A1) and solute carrier family 2 member 2 (SLC2A2) here. SLC2A1, mainly existing in human erythrocytes, brain endothelial cells, and normal placenta, was found to be increased in hepatocellular carcinoma (HCC), while SLC2A2, the major transporter of the normal liver, was decreased in HCC.

AIM

To identify if SLC2A1 and SLC2A2 were associated with immune infiltration in addition to participating in the metabolic reprogramming in HCC.

METHODS

The expression levels of SLC2A1 and SLC2A2 were tested in HepG2 cells, HepG215 cells, and multiple databases. The clinical characteristics and survival data of SLC2A1 and SLC2A2 were examined by multiple databases. The correlation between SLC2A1 and SLC2A2 was analyzed by multiple databases. The functions and pathways in which SLC2A1, SLC2A2, and frequently altered neighbor genes were involved were discussed in String. Immune infiltration levels and immune marker genes associated with SLC2A1 and SLC2A2 were discussed from multiple databases.

RESULTS

The expression level of SLC2A1 was up-regulated, but the expression level of SLC2A2 was down-regulated in HepG2 cells, HepG215 cells, and liver cancer patients. The expression levels of SLC2A1 and SLC2A2 were related to tumor volume, grade, and stage in HCC. Interestingly, the expression levels of SLC2A1 and SLC2A2 were negatively correlated. Further, high SLC2A1 expression and low SLC2A2 expression were linked to poor overall survival and relapse-free survival. SLC2A1, SLC2A2, and frequently altered neighbor genes played a major role in the occurrence and development of tumors. Notably, SLC2A1 was positively correlated with tumor immune infiltration, while SLC2A2 was negatively correlated with tumor immune infiltration. Particularly, SLC2A2 methylation was positively correlated with lymphocytes.

CONCLUSION

SLC2A1 and SLC2A2 are independent therapeutic targets for HCC, and they are quintessential marker molecules for predicting and regulating the number and status of immune cells in HCC.

Identification of a Tumor Immunological Phenotype-Related Gene Signature for Predicting Prognosis, Immunotherapy Efficacy, and Drug Candidates in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the predominant subtype of primary liver cancer and represents a highly heterogeneous disease, making it hard to predict the prognosis and therapy efficacy. Here, we established a novel tumor immunological phenotype-related gene index (TIPRGPI) consisting of 11 genes by Univariate Cox regression and the least absolute shrinkage and selection operator (LASSO) algorithm to predict HCC prognosis and immunotherapy response. TIPRGPI was validated in multiple datasets and exhibited outstanding performance in predicting the overall survival of HCC. Multivariate analysis verified it as an independent predictor and a TIPRGPI-integrated nomogram was constructed to provide a quantitative tool for clinical practice. Distinct mutation profiles, hallmark pathways, and infiltration of immune cells in tumor microenvironment were shown between the TIPRGPI high and low-risk groups. Notably, significant differences in tumor immunogenicity and tumor immune dysfunction and exclusion (TIDE) were observed between the two risk groups, suggesting a better response to immune checkpoint blockade (ICB) therapy of the low-risk group. Besides, six potential drugs binding to the core target of the TIPRGPI signature were predicted via molecular docking. Taken together, our study shows that the proposed TIPRGPI was a reliable signature to predict the risk classification, immunotherapy response, and drugs candidate with potential application in the clinical decision and treatment of HCC. The novel “TIP genes”-guided strategy for predicting the survival and immunotherapy efficacy, we reported here, might be also applied to more cancers other than HCC.

Immunotherapy-Based Treatments of Hepatocellular Carcinoma: AJR Expert Panel Narrative Review

The advent of immunotherapy for patients with hepatocellular carcinoma (HCC) has changed the treatment landscape and conferred survival benefit for patients with advanced HCC who typically have a very poor prognosis. The most pronounced improvements in response, as documented by standardized response criteria based on CT or MRI, have been achieved when immunotherapy is combined with other systemic or locoregional therapies. Immune checkpoint inhibitor treatments result in unique patterns on CT and MRI that challenge the application of conventional response criteria such as RECIST, modified RECIST, and European Association for the Study of the Liver criteria. Thus, newer criteria have been developed to gauge therapy response or disease progression for patients on immunotherapy, including immune-related RECIST (iRECIST) and immune-modified RECIST (imRECIST), though these remain unvalidated. In this review, we describe the current landscape of immunotherapeutic agents used for HCC, summarize results of published studies, review pathobiological mechanisms that provide a rationale for the use of these agents, and report on the status of response assessment for immunotherapy, either alone or in combination with other treatment options. Finally, consensus statements are provided to inform radiologists on essential considerations in the era of a rapidly changing treatment paradigm for patients with HCC.

Liver Immunology, Immunotherapy, and Liver Cancers: Time for a Rethink?

The complex immune system of the liver has a major role in tumor surveillance, but also partly explains why current immune therapies are poorly effective against liver cancers. Known primarily for its tolerogenic capacity, the hepatic immune repertoire also comprises diverse populations of armored immune cells with tumor surveillant roles. In healthy people, these work together to successfully identify malignant cells and prevent their proliferation, thus halting tumor formation. When frontline hepatic immune surveillance systems fail, compromised hepatic immunity, driven by obesity, infection, or other pathological factors, allows primary or secondary liver cancers to develop. Tumor growth promotes the normal tolerogenic immunological milieu of the liver, perhaps explaining why current immunotherapies fail to work. This review explores the complex local liver immune system with the hope of identifying potential therapeutic targets needed to best overcome immunological barriers in the liver to create an environment no longer hostile to immunotherapy for the treatment of liver cancer.

Advances in the interventional therapy of hepatocellular carcinoma originating from the caudate lobe

Hepatocellular carcinoma originating from the caudate lobe, also known as segment I hepatocellular carcinoma, is difficult to treat because of its special location, complex vascular supply, and the proximity of important vessels, bile ducts, and organs. This research is conducted to examine the efficacy and safety of interventional therapy for hepatocellular carcinoma in the caudate lobe.

Conclusion

Superselective chemoembolization and ablation techniques for the treatment of caudate lobe hepatocellular carcinoma still need to be improved. The combination of multiple interventional methods and the application of multiple imaging techniques can improve the effectiveness and safety of interventional therapy for hepatocellular carcinoma in the caudate lobe. Multidisciplinary treatment is also essential to improve the prognosis of patients with caudate lobe hepatocellular carcinoma.

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The anatomical characteristics of the arteries in the caudate lobe hepatocellular carcinoma remains an important factor restricting the success rate of superselective transcatheter arterial chemoembolization.

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The application of multiple imaging techniques may improve the effectiveness and safety of interventional therapy.

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The combination of multiple interventional methods has more advantages than disadvantages.

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Multidisciplinary treatment is increasingly becoming a trend in the treatment of caudate lobe hepatocellular carcinoma.

Encouraging specific biomarkers-based therapeutic strategies for hepatocellular carcinoma

The prevention, early discovery and effective treatment of patients with hepatocellular carcinoma (HCC) remain a global medical challenge. At present, HCC is still mainly treated by surgery, supplemented by vascular embolization, radio frequency, radiotherapy, chemotherapy and biotherapy. The application of multikinase inhibitor sorafenib, chimeric antigen receptor T cells, or PD-1/PD-L1 inhibitors can prolong the median survival of HCC patients. However, the treatment efficacy is still unsatisfactory due to HCC metastasis and postoperative recurrence. During the process of hepatocyte malignant transformation, HCC tissues can express and secrete many types of specific biomarkers, or oncogenic antigen molecules into blood, for example, alpha-fetoprotein, glypican-3, Wnt3a (one of the key signaling molecules in the Wnt/β-catenin pathway), insulin-like growth factor (IGF)-II or IGF-I receptor, vascular endothelial growth factor, secretory clusterin and so on. In addition, combining immunotherapy with non-coding RNAs might improve anti-cancer efficacy. These biomarkers not only contribute to HCC diagnosis or prognosis, but may also become molecular targets for HCC therapy under developing or clinical trials. This article reviews the progress in emerging biomarkers in basic research or clinical trials for HCC immunotherapy.

Efficacy of Sorafenib Combined With Immunotherapy Following Transarterial Chemoembolization for Advanced Hepatocellular Carcinoma: A Propensity Score Analysis

Aim

The aim of the study is to compare the efficacy and safety of monotherapy with a sequential immune checkpoint inhibitor (ICI) programmed cell death protein-1 (PD-1) and its combination with multi-target drug sorafenib after transcatheter arterial chemoembolization (TACE) for advanced hepatocellular carcinoma (HCC).

Methods

We conducted a retrospective evaluation of patients with advanced HCC who had received sequential PD-1 sorafenib (duplex group, n = 25) or monotherapy PD-1 alone (PD-1 group, n = 41) after TACE during April 2018–September 2021. Propensity score matching (PSM) was applied to correct the selection bias, and 22 pairs were created. The objective response rate (ORR), duration of the overall response (DOR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events were analyzed for both groups.

Results

After PSM, the median PFS (7.63 vs. 2.9 months; p = 0.0335) was significantly longer for the duplex group than for the PD-1 group. The median OS (21.63 vs. 16.43 months; p = 0.103) was longer for the duplex group than for the PD-1 group, albeit without any statistical difference. The CR rate, ORR, DCR, and PFS rates at the first, third, and sixth months were higher for the duplex group than for the PD-1 group, wherein the PFS rate of the third and sixth months were statistically different. The OS rates at the sixth, 12th, and 18th months were better for the duplex group than for the PD-1 group, while the 18th-month OS rate (54.5% vs. 33.9%, p = 0.030) were statistically different between them. The most common adverse events after TACE included liver function injury, leukocytopenia, and thrombocytopenia, albeit without any statistical differences between the groups. Cox regression analysis showed that sorafenib combined immunotherapy after TACE and the achieving of CR or PR during the treatment were independent factors affecting PFS. Moreover, CNLC stage-IIIa, TACE frequency ≤2, and achievement of CR or PR were independent influencing factors of OS.

Conclusions

Sequential PD-1 combined with sorafenib therapy after TACE for advanced HCC treatment is safe and effective, especially for patients with good initial treatment response, to further improve the disease prognosis.

An Overview of Hepatocellular Carcinoma After Insufficient Radiofrequency Ablation

Radiofrequency ablation (RFA) is a commonly used treatment for hepatocellular carcinoma (HCC), however, various complex conditions in clinical practice may lead to insufficient radiofrequency ablation (IRFA), allowing residual HCC to survive. In clinical practice and laboratory models, IRFA plays an important role in rapid tumor progression. Therefore, targeting the residual HCC and avoiding IRFA were worthwhile methods. A deeper understanding of IRFA is required; IRFA contributes to the improvement of proliferative activity, migration rates, and invasive capacity, and this may be due to the involvement of multiple complex processes or proteins, including epithelial mesenchymal transitions (EMTs), cancer stem cells (CSCs), autophagy, heat shock proteins (HSPs), changes of non-tumor cells and extracellular matrix, altered immune microenvironment, hypoxia-inducible factors (HIFs), growth factors, epigenetic alterations, and metabolic reprogramming. We focus on the processes of the above mechanisms and possible therapeutic approach, with a review of the literature. Additionally, we recapitulated the construction methods of various experimental models of IRFA (in vivo and in vitro).

Suppression of the transforming growth factor-β signaling pathway produces a synergistic effect of combination therapy with programmed death receptor 1 blockade and radiofrequency ablation against hepatic carcinoma in mice

Primary liver cancer (PLC) significantly affects the health of patients globally owing to its high morbidity and low survival rate. Radiofrequency ablation (RFA) has recently been introduced for the clinical treatment of PLC. However, significant immunosuppressive effects are induced by RFA, which limits its application. This study aimed to explore the potential of combination therapy with RFA by investigating the effects of siRNAs against programmed death receptor 1 (PD-1) and transforming growth factor-β (TGF-β) on the antitumor effect induced by RFA. We observed that compared with si-NC, cell viability was reduced, apoptosis rate was elevated, release of inflammatory factors and percentage of CD3+CD8+ cells were increased, and the PI3K/AKT/mTOR pathway was repressed in the co-culture of RFA-treated H22 cells and CD8+ T cells by transfection with si-PD-1 and si-TGF-β; these effects were further enhanced by co-transfection with si-PD-1 and si-TGF-β. Additionally, in H22 cell xenograft-bearing mice treated with RFA, compared with the si-NC group, repressed tumor growth, prolonged survival, increased production of inflammatory factors and expression of CD3 and CD8 in tumor tissues, and downregulation of the PI3K/AKT/mTOR pathway were observed in the si-PD-1 and si-TGF-β groups; these effects were further enhanced in the si-PD-1 + si-TGF-β group. Taken together, our data revealed that suppression of the TGF-β signaling pathway produced a synergistic antitumor effect of combination therapy with PD-1 blockade and RFA against PLC. [Figure: see text].

Transarterial Embolization Modulates the Immune Response within Target and Nontarget Hepatocellular Carcinomas in a Rat Model

Background Transarterial embolization (TAE) is the most common treatment for hepatocellular carcinoma (HCC); however, there remain limited data describing the influence of TAE on the tumor immune microenvironment. Purpose To characterize TAE-induced modulation of the tumor immune microenvironment in a rat model of HCC and identify factors that modulate this response. Materials and Methods TAE was performed on autochthonous HCCs induced in rats with use of diethylnitrosamine. CD3, CD4, CD8, and FOXP3 lymphocytes, as well as programmed cell death protein ligand-1 (PD-L1) expression, were examined in three cohorts: tumors from rats that did not undergo embolization (control), embolized tumors (target), and nonembolized tumors from rats that had a different target tumor embolized (nontarget). Differences in immune cell recruitment associated with embolic agent type (tris-acryl gelatin microspheres [TAGM] vs hydrogel embolics) and vascular location were examined in rat and human tissues. A generalized estimating equation model and t, Mann-Whitney U, and χ2 tests were used to compare groups. Results Cirrhosis-induced alterations in CD8, CD4, and CD25/CD4 lymphocytes were partially normalized following TAE (CD8: 38.4%, CD4: 57.6%, and CD25/CD4: 21.1% in embolized liver vs 47.7% [P = .02], 47.0% [P = .01], and 34.9% [P = .03], respectively, in cirrhotic liver [36.1%, 59.6%, and 4.6% in normal liver]). Embolized tumors had a greater number of CD3, CD4, and CD8 tumor-infiltrating lymphocytes relative to controls (191.4 cells/mm2 vs 106.7 cells/mm2 [P = .03]; 127.8 cells/mm2 vs 53.8 cells/mm2 [P < .001]; and 131.4 cells/mm2 vs 78.3 cells/mm2 [P = .01]) as well as a higher PD-L1 expression score (4.1 au vs 1.9 au [P < .001]). A greater number of CD3, CD4, and CD8 lymphocytes were found near TAGM versus hydrogel embolics (4.1 vs 2.0 [P = .003]; 3.7 vs 2.0 [P = .01]; and 2.2 vs 1.1 [P = .03], respectively). The number of lymphocytes adjacent to embolics differed based on vascular location (17.9 extravascular CD68+ peri-TAGM cells vs 7.0 intravascular [P < .001]; 6.4 extravascular CD68+ peri-hydrogel embolic cells vs 3.4 intravascular [P < .001]). Conclusion Transarterial embolization-induced dynamic alterations of the tumor immune microenvironment are influenced by underlying liver disease, embolic agent type, and vascular location. © RSNA, 2022 Online supplemental material is available for this article. See also the editorials by Kennedy et al and by White in this issue.

Atezolizumab and bevacizumab with transarterial chemoembolization in hepatocellular carcinoma: the DEMAND trial protocol

The combination of the anti-PD-L1 antibody atezolizumab and the anti-VEGF bevacizumab is the first approved immunotherapeutic regimen for first-line therapy in patients with unresectable hepatocellular carcinoma (HCC), currently approved in more than 80 countries. The efficacy and tolerability of this regimen suggest that the use of atezolizumab + bevacizumab could be extended to the treatment of patients with intermediate-stage HCC in combination with transarterial chemoembolization (TACE). The authors describe the rationale and design of the DEMAND study. This investigator-initiated, multicenter, randomized phase II study is the first trial to evaluate the safety and efficacy of atezolizumab + bevacizumab prior to or in combination with TACE in patients with intermediate-stage HCC. The primary end point is the 24-month survival rate; secondary end points include objective response rate, progression-free survival, safety and quality of life. Clinical Trial Registration: NCT04224636 (ClinicalTrials.gov).

Local Ablative Therapy Associated with Immunotherapy in Locally Advanced Pancreatic Cancer: A Solution to Overcome the Double Trouble?-A Comprehensive Review

Pancreatic ductal adenocarcinoma (PDAC) remains a major killer and is a challenging clinical research issue with abysmal survival due to unsatisfactory therapeutic efficacy. Two major issues thwart the treatment of locally advanced nonresectable pancreatic cancer (LAPC): high micrometastasis rate and surgical inaccessibility. Local ablative therapies induce a systemic antitumor response (i.e., abscopal effect) in addition to local effects. Thus, the incorporation of additional therapies could be key to improving immunotherapy's clinical efficacy. In this systematic review, we explore recent applications of local ablative therapies combined with immunotherapy to overcome immune resistance in PDAC and discuss future perspectives and challenges. Particularly, we describe four chemoradiation studies and nine reports on irreversible electroporation (IRE). Clinically, IRE is the ablative therapy of choice, utilized in all but two clinical trials, and may create a favorable microenvironment for immunotherapy. Various immunotherapies have been used in combination with IRE, such as NK cell- or γδ T cell-based therapy, as well as immune checkpoint inhibitors. The results of the clinical trials presented in this review and the advancement potential of these therapies to phase II/III trials remain unknown. A multiple treatment approach involving chemotherapy, local ablation, and immunotherapy holds promise in overcoming the double trouble of LAPC.

Evaluation of immune-modulating drugs for use in drug-eluting microsphere transarterial embolization

Cancer immunotherapy has yet to reach its full potential due in part to limited response rates and side effects inherent to systemic delivery of immune-modulating drugs. Local administration of immunotherapy using drug-eluting embolic (DEE) microspheres as drug delivery vehicles for direct infusion into tumor-feeding arteries might increase and prolong tumor drug concentrations and reduce systemic drug exposure, potentially improving the risk-to-benefit ratio of these agents. The purpose of this study was to evaluate the ability of four immune modulators affecting two different immune pathways to potentiate replication of immune cells from a woodchuck model of hepatocellular carcinoma. DSR 6434, a Toll-like receptor agonist, and BMS-202, a PD-L1 checkpoint inhibitor, induced immune cell replication and were successfully loaded into radiopaque DEE microspheres in high concentrations. Release of DSR 6434 from the DEE microspheres was rapid (t99% = 0.4 h) upon submersion in a physiologic saline solution while BMS-202 demonstrated a more sustained release profile (t99% = 17.9 h). These findings demonstrate the feasibility of controlled delivery of immune-modulating drugs via a local DEE microsphere delivery paradigm.

JAK/STAT Signaling: Molecular Targets, Therapeutic Opportunities, and Limitations of Targeted Inhibitions in Solid Malignancies

JAK/STAT signaling pathway is one of the important regulatory signaling cascades for the myriad of cellular processes initiated by various types of ligands such as growth factors, hormones, and cytokines. The physiological processes regulated by JAK/STAT signaling are immune regulation, cell proliferation, cell survival, apoptosis and hematopoiesis of myeloid and non-myeloid cells. Dysregulation of JAK/STAT signaling is reported in various immunological disorders, hematological and other solid malignancies through various oncogenic activation mutations in receptors, downstream mediators, and associated transcriptional factors such as STATs. STATs typically have a dual role when explored in the context of cancer. While several members of the STAT family are involved in malignancies, however, a few members which include STAT3 and STAT5 are linked to tumor initiation and progression. Other STAT members such as STAT1 and STAT2 are pivotal for antitumor defense and maintenance of an effective and long-term immune response through evolutionarily conserved programs. The effects of JAK/STAT signaling and the persistent activation of STATs in tumor cell survival; proliferation and invasion have made the JAK/STAT pathway an ideal target for drug development and cancer therapy. Therefore, understanding the intricate JAK/STAT signaling in the pathogenesis of solid malignancies needs extensive research. A better understanding of the functionally redundant roles of JAKs and STATs may provide a rationale for improving existing cancer therapies which have deleterious effects on normal cells and to identifying novel targets for therapeutic intervention in solid malignancies.

Identification of the Tumor Immune Microenvironment and Therapeutic Biomarkers by a Novel Molecular Subtype Based on Aging-Related Genes in Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the most prevalent malignant tumors with poor prognosis. Increasing evidence has revealed that immune cells and checkpoints in the tumor microenvironment (TME) and aging are associated with the prognosis of HCC. However, the association between aging and the tumor immune microenvironment (TIME) in HCC is still unclear.

Methods

RNA expression profiles and clinical data concerning HCC were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Based on differentially expressed aging-related genes (DEAGs), unsupervised clustering was used to identify a novel molecular subtype in HCC. The features of immune cell infiltration and checkpoints were further explored through CIBERSORTx. Enrichment analysis and both univariate and multivariate Cox analyses were conducted to construct a 3-gene model for predicting prognosis and chemosensitivity. Finally, the mRNA and protein expression levels of the 3 genes were verified in HCC and other cancers through database searches and experiments.

Results

Eleven differentially expressed AGs (GHR, APOC3, FOXM1, PON1, TOP2A, FEN1, HELLS, BUB1B, PPARGC1A, PRKDC, and H2AFX) correlated with the prognosis of HCC were used to divide HCC into two subtypes in which the prognosis was different. In cluster 2, which had a poorer prognosis, the infiltration of naive B cells and monocytes was lower in the TCGA and GEO cohorts, while the infiltration of M0 macrophages was higher. In addition, the TCGA cohort indicated that the microenvironment of cluster 2 had more immunosuppression through immune checkpoints. Enrichment analysis suggested that the MYC and E2F targets were positively associated with cluster 2 in the TCGA and GEO cohorts. Additionally, 3 genes (HMGCS2, SLC22A1, and G6PD) were screened to construct the prognostic model through univariate/multivariate Cox analysis. Then, the model was validated through the TCGA validation set and GEO dataset (GSE54236). Cox analysis indicated that the risk score was an independent prognostic factor and that patients in the high-risk group were sensitive to multiple targeted drugs (sorafenib, gemcitabine, rapamycin, etc.). Finally, significantly differential expression of the 3 genes was detected across cancers.

Conclusion

We systematically described the immune differences in the TME between the molecular subtypes based on AGs and constructed a novel three-gene signature to predict prognosis and chemosensitivity in patients with HCC.

Novel Perspectives in Immune Checkpoint Inhibitors and the Management of Non-Alcoholic Steatohepatitis-Related Hepatocellular Carcinoma

Immune checkpoint inhibitors have revolutionised the systemic treatment of advanced hepatocellular carcinoma. Although phase III trials, testing single agent nivolumab and pembrolizumab, failed to meet their primary endpoints, the combination of atezolizumab and bevacizumab has demonstrated a remarkable objective response and unprecedented survival benefits, replacing sorafenib as the standard first-line treatment for advanced hepatocellular carcinoma. Despite these successes observed in immune checkpoint inhibitors in the management of advanced hepatocellular carcinoma, not all patients responded to treatment, which has led to the search of risk factors and biomarkers that could predict the response to immune checkpoint inhibitors. Recent translational studies have begun to shed light on the impact of an underlying liver disease, namely NASH, which might affect the response to immune checkpoint inhibitors. In addition, antidrug-antibody and gene expression assays have demonstrated promises in predicting the response to immune checkpoint inhibitors. In this article, we will provide an overview of the use of ICI in the management of advanced HCC, review the evidence that surrounds the recent controversy regarding NASH-HCC, and discuss potential biomarkers that predict the response to immune checkpoint inhibitors.

Expression of FOXM1 and PLK1 predicts prognosis of patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most frequently encountered malignant tumor types and to improve its treatment, effective prognostic biomarkers are urgently required. Cell cycle dysregulation is a significant feature of cancer progression. The aim of the present study was to estimate the expression levels of forkhead box protein M1 (FOXM1) and polo-like kinase 1 (PLK1), both of which have essential roles in cell cycle regulation, and determine their prognostic value in HCC. To this end, FOXM1 and PLK1 expression levels were assessed in The Cancer Genome Atlas and International Cancer Genome Consortium Japan HCC cohorts, and the associations between their co-expression were determined via Pearson's correlation analysis. Furthermore, the overall survival and disease-free survival in these cohorts for different FOXM1 and PLK1 expression statuses were analyzed. In vitro knockdown experiments were also performed using Huh7 cells. The results obtained indicated overexpression of FOXM1 and PLK1 in HCC tumor tissues as well as a positive correlation between FOXM1 and PLK1 expression. The results also suggested that both FOXM1 and PLK1 are required for HCC cell proliferation. In addition, upregulation of FOXM1 and PLK1 was indicated to be associated with poor prognosis of patients with HCC. However, only their coordinated overexpression was identified as an independent prognostic factor for HCC.

Why does survival of hepatocellular carcinoma patients remain so low? Key stumbling blocks and questions in preclinical and clinical development

INTRODUCTION

: Hepatocellular carcinoma (HCC) is a complex disease which involves diverse molecular pathways and etiologies. In recent years, several new systemic treatments have improved survival in advanced stage disease, but numerous significant challenges remain. No significant improvements have been achieved in the intermediate stage disease; this may be attributed to the difficulties in stratification of patients and the broad spectrum of clinical situations in terms of tumor burden and liver function.

AREAS COVERED

: This article considers the recent progress in first- and second-line therapy for advanced HCC. Investigational strategies conducted in intermediate stage HCC, which involve mainly combination therapy with locoregional approaches and systemic drugs, antiangiogenics, immunotherapies (or both), are then examined. Later, the paper offers insights on the questions and challenges that lie ahead for treating HCC.

EXPERT OPINION

Clinical and biomolecular markers for the stratification of patients are needed for therapeutic progress. Further molecular profiling data could enhance our knowledge of the molecular pathways underlying this tumor and facilitate the identification of targetable aberrations. This could offer opportunities for precision medicine approaches and improved survival.

Identification of the Expression Patterns and Potential Prognostic Role of 5-Methylcytosine Regulators in Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer with a poor prognosis. 5-methylcytosine (m5C) modification plays a nonnegligible role in tumor pathogenesis and progression. However, little is known about the role of m5C regulators in HCC.

Methods: Based on 9 m5C regulators, the m5C modification patterns of HCC samples extracted from public databases were systematically evaluated and correlated with tumor immune and prognosis characteristics. An integrated model called the “m5Cscore” was constructed using principal component analysis, and its prognostic value was evaluated.

Results: Almost all m5C regulators were differentially expressed between HCC and normal tissues. Through unsupervised clustering, three different m5Cclusters were ultimately uncovered; these clusters were characterized by differences in prognosis, immune cell infiltration, and pathway signatures. The m5Cscore was constructed to quantify the m5C modifications of individual patients. Subsequent analysis revealed that the m5Cscore was an independent prognostic factor of HCC and could be a novel indicator to predict the prognosis of HCC.

Conclusion: This study comprehensively explored and systematically profiled the features of m5C modification in HCC. m5C modification patterns play a crucial role in the tumor immune microenvironment (TIME) and prognosis of HCC. The m5Cscore provides a more holistic understanding of m5C modification in HCC and provides a practical tool for predicting the prognosis of HCC. This study will help clinicians identify effective indicators of HCC to improve the poor prognosis of this disease.

The effects of immune checkpoint modulators on the clinical course of patients with resectable hepatocellular carcinoma

Background/Aim

Immune checkpoint proteins regulating T-cell mediated anti-tumor immunity have been reported to affect clinical outcomes in multiple malignancies. This study aimed to investigate the prognostic effect of histological expression of immune checkpoint proteins in patients with resected hepatocellular carcinoma (HCC).

Methods

A total of 221 patients with HCC who underwent curative resection were included. Expression of programmed-cell death ligand-1 (PD-L1) in tumor cells (tPD-L1) and tumor infiltrating mononuclear cells (TIMCs) (iPD-L1), programmed-cell death-1 in TIMCs (iPD-1), and cytotoxic T lymphocyte antigen-4 in TIMCs (iCTLA-4) were measured immunohistochemically.

Results

Histo-positivity for iCTLA-4, iPD-1, iPD-L1, and tPD-L1 was 32.1%, 42.5%, 35.3%, and 14.9%, respectively. Multivariate logistic analyses revealed that male sex and tumor >5 cm were variables related to iCTLA-4 positivity (odds ratio [OR], 0.46 and 1.94, respectively; P<0.05). Poor differentiation was related to PD-L1 expression in both tumor cells and TIMCs (OR, 2.88 and 3.46, respectively; P<0.05). Microvascular invasion was significantly associated only with iPD-L1 (OR, 2.24; P<0.05). In time-dependent outcome analyses, expression of immune checkpoint proteins in TIMCs (i.e., iCTLA-4, iPD-1, and iPD-L1) was significantly related to longer overall survival and non-cancer-related survival (all P<0.05), but not to time-to-recurrence or cancer-specific deaths. Concurrent activation of the PD-1:PD-L1 and CTLA-4 pathways predicted improved outcomes in terms of overall survival and non-cancer related survival (P=0.06 and P=0.03, respectively).

Conclusions

Immune checkpoint proteins upregulated in TIMCs in HCC tissues have individual and additive effects in prolonging the survival of patients, specifically in terms of survival not related to cancer recurrence.

Correlation Between Contrast-Enhanced Ultrasound and Immune Response of Distant Hepatocellular Carcinoma After Radiofrequency Ablation in a Murine Model

OBJECTIVES

To investigate the relationships between contrast-enhanced ultrasound (CEUS) and the immune status of a distant tumor after radiofrequency ablation (RFA) in a mouse model of hepatocellular carcinoma (HCC).

METHODS

Twenty-four mice with two liver tumors were randomized into two groups. RFA was performed on the left tumor in the RFA group. Growth of the right tumors in both groups was monitored after RFA. According to tumor growth, two time points at which tumor growth was halted and restored were selected for study. Then, another 24 mice were randomized into RFA and non-RFA groups. The CEUS parameters, apoptosis, CD8+ T cell, and vasculogenic mimicry (VM) of the right tumors were analyzed on the two aforementioned time points in each group.

RESULTS

Days 3 and 6 were selected as the time points of tumor retardation and progressive growth, respectively. The different immune status of the distant tumors at the two time points after RFA was confirmed by CD8+ T cell and apoptosis (both P < 0.001). Peak intensity, time to peak, area wash-in, and area wash-out of the CEUS parameters increased significantly in the day-6 RFA group versus the day-3 RFA group (P < .001, P = .017, P = .005, P = .002, respectively). VM of the day-6 RFA group was higher than that of the day-3 RFA group (P = .003).

CONCLUSIONS

CEUS maybe a good method to follow the immune response after RFA in an advanced HCC mouse model.

Systemic Therapy for Hepatocellular Carcinoma: Current Updates and Outlook

Hepatocellular carcinoma (HCC) has emerged the culprit of cancer-related mortality worldwide with its dismal prognosis climbing. In recent years, ground-breaking progress has been made in systemic therapy for HCC. Targeted therapy based on specific signaling molecules, including sorafenib, lenvatinib, regorafenib, cabozantinib, and ramucirumab, has been widely used for advanced HCC (aHCC). Immunotherapies such as pembrolizumab and nivolumab greatly improve the survival of aHCC patients. More recently, synergistic combination therapy has boosted first-line (atezolizumab in combination with bevacizumab) and second-line (ipilimumab in combination with nivolumab) therapeutic modalities for aHCC. This review aims to summarize recent updates of systemic therapy relying on the biological mechanisms of HCC, particularly highlighting the approved agents for aHCC. Adjuvant and neoadjuvant therapy, as well as a combination with locoregional therapies (LRTs), are also discussed. Additionally, we describe the promising effect of traditional Chinese medicine (TCM) as systemic therapy on HCC. In this setting, the challenges and future directions of systemic therapy for HCC are also explored.

Immunotherapies for hepatocellular carcinoma

Liver cancer, more specifically hepatocellular carcinoma (HCC), is the second leading cause of cancer-related death and its incidence is increasing globally. Around 50% of patients with HCC receive systemic therapies, traditionally sorafenib or lenvatinib in the first line and regorafenib, cabozantinib or ramucirumab in the second line. In the past 5 years, immune-checkpoint inhibitors have revolutionized the management of HCC. The combination of atezolizumab and bevacizumab has been shown to improve overall survival relative to sorafenib, resulting in FDA approval of this regimen. More recently, durvalumab plus tremelimumab yielded superior overall survival versus sorafenib and atezolizumab plus cabozantinib yielded superior progression-free survival. In addition, pembrolizumab monotherapy and the combination of nivolumab plus ipilimumab have received FDA Accelerated Approval in the second-line setting based on early efficacy data. Despite these major advances, the molecular underpinnings governing immune responses and evasion remain unclear. The immune microenvironment has crucial roles in the development and progression of HCC and distinct aetiology-dependent immune features have been defined. Inflamed and non-inflamed classes of HCC and genomic signatures have been associated with response to immune-checkpoint inhibitors, yet no validated biomarker is available to guide clinical decision-making. This Review provides information on the immune microenvironments underlying the response or resistance of HCC to immunotherapies. In addition, current evidence from phase III trials on the efficacy, immune-related adverse events and aetiology-dependent mechanisms of response are described. Finally, we discuss emerging trials assessing immunotherapies across all stages of HCC that might change the management of this disease in the near future.

Immunomodulation for hepatocellular carcinoma therapy: current challenges

PURPOSE OF REVIEW

The emergence of novel immunotherapies, such as immune-checkpoint inhibitors has changed the landscape of systemic cancer treatment. In hepatocellular carcinoma (HCC) patients, despite initial enthusiasm, the proportion of responders to immune-checkpoint inhibitors remains low. We provide a brief update of this rapidly evolving field, with specific focus on the development in the field of predictive factors and the immunomodulation induced by locoregional therapies.

RECENT FINDINGS

Even if the immune contexture of HCC before the treatment remains the most promising predictive marker for response to immunotherapies, recent findings show that the cause of HCC may have also a key role. Specific inflammatory mechanisms induced by NASH may result in limited efficacy of immunotherapy compared with viral HCC. Other recent findings showed that percutaneous ablations are responsible for intratumoral immune changes and systemic immune system activation that may help to prevent recurrence when combined with immunotherapies. In case of multifocal HCC, transarterial therapies (TACE and SIRT) may help to turn a cold tumor type to a hot tumor type and could be associated with immune-checkpoint inhibitors to improve outcomes.

SUMMARY

The future HCC management will focus on patient stratification for specific immunotherapies depending on the signature and cause of HCC and the best combined approaches in which locoregional therapies may play a pivotal role.

Current progress of immune checkpoint inhibitors in the treatment of advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer worldwide. The onset of the disease is occult and develops rapidly. As a result, the disease is often detected when it is already in advanced stages, resulting in patients losing the best opportunity for liver transplantation and surgical treatment. Therefore, effective treatment of HCC is particularly important in clinical practice. During the past decades, there have been considerable advances in the treatment of HCC, and immunotherapy is increasingly recognized as a promising approach in clinical trials. In this review, an overview of immune checkpoint (ICP) inhibitors (ICIs) and their role in the treatment of liver cancers, particularly advanced HCC, is presented and the recent therapeutic progress with treatment with different ICIs alone or in combination with other methods/therapeutic agents is summarized. In addition, the identification of biomarkers to predict treatment response and the limitations of current ICIs are analyzed, and future directions for ICI treatment are discussed.

Transarterial Chemoembolization Combined With Immune Checkpoint Inhibitors and Tyrosine Kinase Inhibitors for Unresectable Hepatocellular Carcinoma: Efficacy and Systemic Immune Response

Background

Locoregional therapy combined with systemic therapy can further improve the prognoses for HCC. However, the efficacy of TACE combined with ICIs and TKIs for HCC and whether this triple therapy can activate systemic immune response are still unknown.

Purpose

To identify the efficacy of TACE+ICIs+TKIs for unresectable hepatocellular carcinoma (uHCC) and its effect on systemic immunity.

Materials and Methods

This single-center retrospective study was approved by the Institutional Review Board. From August 1, 2019, to March 30, 2021, patients with uHCC who received the combination therapy of TACE+ICIs+TKIs were included. Peripheral blood samples were collected at baseline and once a month for 4 months after treatment. Lymphocyte subsets were measured by flow cytometry. Immunoglobulins were measured using the immune turbidimetric method. The dynamic change trend of circulating parameters was tested using simple linear regression.

Results

Fifty-three patients with a mean age of 59 ± 10.6 years were included. TTP was 8.0 months (95% CI, 5.5–10.5) and PFS was 8.5 months (95% CI, 5.4–11.5). ORR was 52.8% and DCR was 81.1%. Twenty patients had completed analysis of biomarkers in peripheral blood. For cellular immune response, the level of circulating CD8⁺, CD3⁺ T cells and NK cells increased, the frequency of CD4⁺T cells and the CD4⁺/CD8⁺ ratio decreased, and among them, CD8⁺ T cells increased significantly. For humoral immune response, there was a significant decrease in B cells and a significant increase in Ig G, Ig κ, and Ig λ. Moreover, Ig G, Ig κ, and Ig λ were related to tumor response.

Conclusion

TACE+ICIs+TKIs showed considerable efficacy in patients with uHCC. This triple therapy activated not only cell immune but also humoral immune activation. Circulating Ig G, Ig λ, and Ig κ can serve as potential biomarkers.

The dual checkpoint blockade in unresectable hepatocellular carcinoma: Opportunities emerging in clinical trials

INTRODUCTION

To prevent damage from an immune response against autoantigens and toxins originating from the gut, the liver promotes an immune-tolerant milieu providing fertile ground for immune escape of cancer cells. Therefore, the use and evaluation of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) is a treatment rationale.

AREA COVERED

In this article, we discuss the role of the dual ICIs blockade in advanced HCC, covering the biological basis for their combination, their mechanism of action, and the results of the early phase studies testing nivolumab plus ipilimumab and durvalumab plus tremelimumab. Furthermore, we provide the results of the phase III HIMALAYA trial and an overview of the ongoing trials investigating the dual ICIs in different disease stages.

EXPERT OPINION

The potential approval of the dual ICIs blockade strategies for advanced HCC will set the entry of antiangiogenic-free options, expanding the proportion of patients eligible for a first-line treatment. However, it will pose a series of clinical challenges with a sizeable proportion of patients, namely Child-Pugh B, elderly, and immunocompromised patients, still marginalized. Also, given the rate of disease progression, identifying reliable predictive biomarkers is crucial to inform treatment choice and sequences. Finally, the compelling response rate of such combinations is paving the way for their evaluation in earlier stages.

Dual immune checkpoint blockade in hepatocellular carcinoma: where do we stand?

Hepatocellular carcinoma (HCC) represents the fourth most common cause of cancer-related death. Surgery, local ablative therapies and liver transplantation are the only potentially curative strategies, but the majority of patients present with advanced disease at diagnosis or develop recurrence after surgery. In recent years, immunotherapy for HCC has received growing interest, and one of the most promising strategies is the association of two immune checkpoint inhibitors (ICIs), which has already demonstrated its potential in other solid tumors such as melanoma and renal cell carcinoma. Herein, we discuss the role and the biologic rationale of dual immune checkpoint blockade in HCC patients, focusing on the two ICI combinations: nivolumab plus ipilimumab and durvalumab plus tremelimumab.

Distinctive features of hepatocellular carcinoma in non-alcoholic fatty liver disease

Hepatocellular carcinoma (HCC) is on the rise globally, causing more than 800 thousand deaths annually, with an estimated annual percent change of 0.51 for causes other than viral hepatitis, including nonalcoholic fatty liver disease (NAFLD). The incidence of NAFLD-related HCC is peaking in several Far East regions (6-12% vs. 2-3% in Western Europe and USA), HCC risk being mainly driven by the epidemic of obesity and diabetes, both favored by an unhealthy diet and sedentary lifestyle. Under inherited susceptibility outlined by such genetic markers as variants in PNPLA3, TM6SF2 and MBOAT7, neoplastic transformation of NAFLD is driven by sublethal lipotoxicity consequent to hepatocyte lipid overload, whereas a myriad of factors spanning from subverted circadian homeostasis and gut dysbiosis to alcohol abuse and tobacco may interact as risk modifiers. At variance with viral HCC, NAFLD-HCC shows a frequent association with cardiovascular co-morbidities, absence of cirrhosis in up to half of patients and an association with persistently normal transaminase values. All these misleading features of NAFLD-related HCC account for the low uptake of surveillance and linkage to curative treatments that has been reported in patients with this cancer, a downside that could be attenuated when scores for cost-effective risk stratification become available.

Glycosylated 4-methylumbelliferone as a targeted therapy for hepatocellular carcinoma

BACKGROUND & AIMS

Reaching efficacious drug delivery to target cells/tissues represents a major obstacle in the current treatment of solid malignancies including hepatocellular carcinoma (HCC). In this study, we developed a pipeline to selective add complex-sugars to the aglycone 4-methylumbelliferone (4MU) to help their bioavailability and tumour cell intake.

METHODS

The therapeutic efficacy of sugar-modified rutinosyl-4-methylumbelliferone (4MUR) and 4MU were compared in vitro and in an orthotopic HCC model established in fibrotic livers. The mechanistic bases of its selective target to liver tumour cells were evaluated by the interaction with asialoglycoprotein receptor (ASGPR), the mRNA expression of hyaluronan synthases (HAS2 or HAS3) and hyaluronan deposition.

RESULTS

4MUR showed a significant antiproliferative effect on liver tumoural cells as compared to non-tumoural cells in a dose-dependent manner. Further analysis showed that 4MUR is incorporated mostly into HCC cells by interaction with ASGPR, a receptor commonly overexpressed in HCC cells. 4MUR-treatment decreased the levels of HAS2 and HAS3 and the cytoplasmic deposition of hyaluronan. Moreover, 4MUR reduced CFSC-2G activation, hence reducing the fibrosis. In vivo efficacy showed that 4MUR treatment displayed a greater tumour growth inhibition and increased survival in comparison to 4MU. 4MUR administration was associated with a significant reduction of liver fibrosis without any signs of tissue damage. Further, 60% of 4MUR treated mice did not present macroscopically tumour mass post-treatment.

CONCLUSION

Our results provide evidence that 4MUR may be used as an effective HCC therapy, without damaging non-tumoural cells or other organs, most probably due to the specific targeting.

Targets of immunotherapy for hepatocellular carcinoma: An update

Hepatocellular carcinoma, the most common primary liver cancer, in an immunogenic tumor with a poor prognosis because these tumors are diagnosed at late stages. Although, surgical resection, ablation, liver transplant, and locoregional therapies are available for early stages; however, there are yet no effective treatment for advanced and recurrent tumors. Immune checkpoint inhibitor therapy and adoptive cell transfer therapy has gained the popularity with some positive results because these therapies overcome anergy and systemic immune suppression. However, still there is a lack of an effective treatment and thus there is an unmet need of a novel treatment. At present, the focus of the research is on oncolytic viral therapy and combination therapy where therapies including radiotherapy, immune checkpoint therapy, adoptive cell transfer therapy, and vaccines are combined to get an additive or synergistic effect enhancing the immune response of the liver with a cytotoxic effect on tumor cells. This review discusses the recent key development, the basis of drug resistance, immune evasion, immune tolerance, the available therapies based on stage of the tumor, and the ongoing clinical trials on immune checkpoint inhibitor therapy, adoptive cell transfer therapy, oncolytic viral vaccine therapy, and combination therapy.

Immunotherapy and Gene Therapy: New Challenges in the Diagnosis and Management of Drug-Induced Liver Injury

In the last 5 years, the landscape of oncologic treatment has been deeply modified with the development and use of immune checkpoint inhibitors (ICIs) that exert their antitumoral effect by reverting the exhausted phenotype of tumor-infiltrating lymphocytes. This innovative therapeutic strategy has widely changed the prognosis of some advanced neoplastic diseases such as melanoma and lung cancer, providing durable remission for a significant number of patients. Unfortunately, immune-related adverse events (irAEs), especially ICI-induced hepatitis, may be very severe in some cases, impairing the prognosis of the patient. Guidelines available today on the diagnosis and management of ICI-induced hepatitis are mainly based on expert opinions and case series. This lack of large data is explained not only by the low incidence of hepatic adverse events but also by their clinical heterogeneity and variable severity. In this article, we will review the clinical, biological, and histological characteristics of ICI-induced liver injury. We will discuss the current knowledge on their pathological mechanisms and their therapeutic strategy based on immunosuppressive treatment for more severe cases. Regarding severity assessment, we will discuss the gap between the oncologist and the hepatologist's point of view, highlighting the need for multidisciplinary management. While initially developed for notably less frequent diseases than neoplastic ones, gene therapy is going to be a revolution for the treatment of diseases not responding to pharmacological therapy. Limited but growing data describe liver injury after the administration of such therapy whose exact physiopathology remains unknown. In this article, we will discuss the available data supporting the role of gene therapies in the onset of drug-induced liver injury and related mechanisms. We will describe the clinical context, the biological and histological features, and the management currently proposed.

Immunotherapy in liver transplantation for hepatocellular carcinoma: Pros and cons

Liver transplantation (LT) has emerged as a curative strategy for hepatocellular carcinoma (HCC), but contributes to a higher predisposition to HCC recurrence in the immunosuppression context, especially for tumors beyond the Milan criteria. Although immunotherapy has dramatically improved survival for immunocompetent patients and has become the standard of care for a variety of tumors, including HCC, it is mainly used outside the scope of organ transplantation owing to potentially fatal allograft rejection. Nevertheless, accumulative evidence has expanded the therapeutic paradigms of immunotherapy for HCC, from downstaging or bridging management in the pretransplant setting to the salvage or adjuvant strategy in the posttransplant setting. Generally, immunotherapy mainly includes immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT) and vaccine therapy. ICIs, followed by ACT, have been most investigated in LT, with some promising results. Because of the complex tumor microenvironment and immunoreactivity when immunosuppressants are combined with immunotherapy, it is difficult to reach formulations for immunosuppressant adjustment and the optimal selection of immunotherapy as well as patients. In addition, the absence of effective biomarkers for identifying rejection and tumor response is still an unresolved barrier to successful clinical immunotherapy applications for LT. In this review, we comprehensively summarize the available evidence of immunotherapy used in LT that is specific to HCC. Moreover, we discuss clinically concerning issues regarding the concurrent goals of graft protection and antitumor response.

Combination of Ablation and Immunotherapy for Hepatocellular Carcinoma: Where We Are and Where to Go

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide and is increasing in incidence. Local ablative therapy plays a leading role in HCC treatment. Radiofrequency (RFA) is one of the first-line therapies for early local ablation. Other local ablation techniques (e.g., microwave ablation, cryoablation, irreversible electroporation, phototherapy.) have been extensively explored in clinical trials or cell/animal studies but have not yet been established as a standard treatment or applied clinically. On the one hand, single treatment may not meet the needs. On the other hand, ablative therapy can stimulate local and systemic immune effects. The combination strategy of immunotherapy and ablation is reasonable. In this review, we briefly summarized the current status and progress of ablation and immunotherapy for HCC. The immune effects of local ablation and the strategies of combination therapy, especially synergistic strategies based on biomedical materials, were discussed. This review is hoped to provide references for future researches on ablative immunotherapy to arrive to a promising new era of HCC treatment.

Immune suppressive checkpoint interactions in the tumour microenvironment of primary liver cancers

Liver cancer is one of the most prevalent cancers, and the third most common cause of cancer-related mortality worldwide. The therapeutic options for the main types of primary liver cancer-hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA)-are very limited. HCC and CCA are immunogenic cancers, but effective immune-mediated tumour control is prevented by their immunosuppressive tumour microenvironment. Despite the critical involvement of key co-inhibitory immune checkpoint interactions in immunosuppression in liver cancer, only a minority of patients with HCC respond to monotherapy using approved checkpoint inhibitor antibodies. To develop effective (combinatorial) therapeutic immune checkpoint strategies for liver cancer, in-depth knowledge of the different mechanisms that contribute to intratumoral immunosuppression is needed. Here, we review the co-inhibitory pathways that are known to suppress intratumoral T cells in HCC and CCA. We provide a detailed description of insights from preclinical studies in cellular crosstalk within the tumour microenvironment that results in interactions between co-inhibitory receptors on different T-cell subsets and their ligands on other cell types, including tumour cells. We suggest alternative immune checkpoints as promising targets, and draw attention to the possibility of combined targeting of co-inhibitory and co-stimulatory pathways to abrogate immunosuppression.

Current Perspectives on the Immunosuppressive Niche and Role of Fibrosis in Hepatocellular Carcinoma and the Development of Antitumor Immunity

Immune checkpoint inhibitors have become the mainstay of treatment for hepatocellular carcinoma (HCC). However, they are ineffective in some cases. Previous studies have reported that genetic alterations in oncogenic pathways such as Wnt/β-catenin are the important triggers in HCC for primary refractoriness. T-cell exhaustion has been reported in various tumors and is likely to play a prominent role in the emergence of HCC due to chronic inflammation and cirrhosis-associated immune dysfunction. Immunosuppressive cells including regulatory T-cells and tumor-associated macrophages infiltrating the tumor are associated with hyperprogressive disease in the early stages of immune checkpoint inhibitor treatment. In addition, stellate cells and tumor-associated fibroblasts create an abundant desmoplastic environment by producing extracellular matrix. This strongly contributes to epithelial to mesenchymal transition via signaling activities including transforming growth factor beta, Wnt/β-catenin, and Hippo pathway. The abundant desmoplastic environment has been demonstrated in pancreatic ductal adenocarcinoma and cholangiocarcinoma to suppress cytotoxic T-cell infiltration, PD-L1 expression, and neoantigen expression, resulting in a highly immunosuppressive niche. It is possible that a similar immunosuppressive environment is created in HCC with advanced fibrosis in the background liver. Although sufficient understanding is required for the establishment of immune therapies of HCC, further investigations are still required in this field.

Photodynamic therapy: A next alternative treatment strategy for hepatocellular carcinoma?

Liver cancer is one of the most common cancers in the world. Of all types of liver cancer, hepatocellular carcinoma (HCC) is known to be the most frequent primary liver malignancy and has seriously compromised the health status of the general population. Locoregional thermal ablation techniques such as radiofrequency and microwave ablation, have attracted attention in clinical practice as an alternative strategy for HCC treatment. However, their aggressive thermal effect may cause undesirable complications such as hepatic decompensation, hemorrhage, bile duct injury, extrahepatic organ injuries, and skin burn. In recent years, photodynamic therapy (PDT), a gentle locoregional treatment, has attracted attention in ablation therapy for patients with superficial or luminal tumors as an alternative treatment strategy. However, some inherent defects and extrinsic factors of PDT have limited its use in clinical practice for deep-seated HCC. In this contribution, the aim is to summarize the current status and challenges of PDT in HCC treatment and provide potential strategies to overcome these deficiencies in further clinical translational practice.

Alpha-fetoprotein response predicts treatment outcomes in patients with unresectable hepatocellular carcinoma receiving immune checkpoint inhibitors with or without tyrosine kinase inhibitors or locoregional therapies

Combined immune checkpoint inhibitors (ICIs) along with tyrosine kinase inhibitors (TKIs) and locoregional therapies have been used increasingly to treat hepatocellular carcinoma (HCC). Biomarkers are required to predict the treatment efficacy of ICIs with or without combination therapies in patients with unresectable HCC. This study enrolled 95 consecutive patients with unresectable HCC from May 2017 to June 2021 from two hospitals retrospectively. Of the 95 patients, 15 and 80 had Barcelona Clinic Liver Cancer stages B and C, respectively. The median ICI treatment duration was 3.43 (1.87-7.87) months, and 77 patients received combination therapies. Radiological imaging was not performed in 13 patients. Objective response and disease control rates were 27.4% and 53.7%, respectively. The duration of progression-free survival (PFS) and overall survival (OS) was 4.07 (1.59-6.54) months and 14.53 (6.93-22.14) months, respectively. Alpha-fetoprotein (AFP) response was defined as a decline of >15% in the serum AFP level within the initial 3 months of ICI therapy according to Youden's index. AFP response was determined to be a predictor of disease control (odds ratio: 11.657, 95% confidence interval [CI]: 2.834-47.941, P=.001). Macrovascular invasion (MVI), AFP response (hazard ratio [HR]: 0.488, 95% CI: 0.255-0.934, P=.030), combination therapy, and disease control were predictors of PFS, and MVI, AFP response (HR: 0.344, 95% CI: 0.160-0.737, P=.006), and disease control were predictors of OS. AFP response was a predictor of disease control, PFS, and OS. These findings indicate that AFP response can serve as a biomarker to predict treatment outcomes in patients with unresectable HCC receiving ICIs with or without TKIs or locoregional therapies.

Combined treatments in hepatocellular carcinoma: Time to put them in the guidelines?

The time for battling cancer has never been more suitable than nowadays and fortunately against hepatocellular carcinoma (HCC) we do have a far-reaching arsenal. Moreover, because liver cancer comprises a plethora of stages-from very early to advanced disease and with many treatment options–from surgery to immunotherapy trials–it leaves the clinician a wide range of options. The scope of our review is to throw light on combination treatments that seem to be beyond guidelines and to highlight these using evidence-based analysis of the most frequently used combination therapies, discussing their advantages and flaws in comparison to the current standard of care. One particular combination therapy seems to be in the forefront: Transarterial chemoembolization plus ablation for medium-size non-resectable HCC (3-5 cm), which is currently at the frontier between Barcelona Clinic Liver Cancer classification A and B. Not only does it improve the outcome in contrast to each individual therapy, but it also seems to have similar results to surgery. Also, the abundance of immune checkpoint inhibitors that have appeared lately in clinical trials are bringing promising results against HCC. Although the path of combination therapies in HCC is still filled with uncertainty and caveats, in the following years the hepatology and oncology fields could witness an HCC guideline revolution.

Strategies to Improve the Antitumor Effect of Immunotherapy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), one of the most fatal malignancies in the world, is usually diagnosed in advanced stages due to late symptom manifestation with very limited therapeutic options, which leads to ineffective intervention and dismal prognosis. For a decade, tyrosine kinase inhibitors (TKIs) have offered an overall survival (OS) benefit when used in a first-line (sorafenib and lenvatinib) and second-line setting (regorafenib and cabozantinib) in advanced HCC, while long-term response remains unsatisfactory due to the onset of primary or acquired resistance. Recently, immunotherapy has emerged as a promising therapy in the treatment of several solid tumors, such as melanoma and non-small cell lung cancer. Moreover, as the occurrence of HCC is associated with immune tolerance and immunosurveillance escape, there is a potent rationale for employing immunotherapy in HCC. However, immunotherapy monotherapy, mainly including immune checkpoint inhibitors (ICIs) that target checkpoints programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), and the cytotoxic T lymphocyte antigen-4 (CTLA-4), has a relatively low response rate. Thus, the multi-ICIs or the combination of immunotherapy with other therapies, like antiangiogenic drugs and locoregional therapies, has become a novel strategy to treat HCC. Combining different ICIs may have a synergistical effect attributed to the complementary effects of the two immune checkpoint pathways (CTLA-4 and PD-1/PD-L1 pathways). The incorporation of antiangiogenic drugs in ICIs can enhance antitumor immune responses via synergistically regulating the vasculature and the immune microenvironment of tumor. In addition, locoregional treatments can improve antitumor immunity by releasing the neoplasm antigens from killed tumor cells; in turn, this antitumor immune response can be intensified by immunotherapy. Therefore, the combination of locoregional treatments and immunotherapy may achieve greater efficacy through further synergistic effects for advanced HCC. This review aims to summarize the currently reported results and ongoing trials of the ICIs-based combination therapies for HCC to explore the rational combination strategies and further improve the survival of patients with HCC.

CD169-positive macrophages enhance abscopal effect of radiofrequency ablation therapy in liver cancer

Radiofrequency ablation (RFA) is a widely used and effective treatment for primary or metastatic liver cancer with small-size lesions. However, the therapeutic effectiveness of RFA in controlling metastatic lesion or recurrence is still limited. As the major cell population in tumor microenvironment (TME), macrophages have been reported to be recruited to RFA-treated lesion, but their roles are still unclear. Herein, we successfully established the mouse model mimicking RFA-induced abscopal effect, in which RFA eliminated the local orthotopic liver tumor but failed to control growth of distant tumor. Correspondently, RFA suppressed protumoral activation of local tumor-associated macrophages (TAMs), but failed to reprogram TAMs in distance. Importantly, although RFA led to reduced proportion of hepatic CD169⁺ macrophages in local and decreased expression of immune inhibitory molecules Tim-3 and PD-L1, these alterations were not observed for CD169⁺ macrophages in distant TME. Further RNA-seq and flow cytometry analysis showed that hepatic CD169⁺ macrophages contributed to reprograming TME through recruiting CD8⁺ T/NK cells and suppressing accumulation of MDSCs/Tregs. Consistently, depletion of CD169⁺ macrophages in CD169-DTR mouse greatly promoted liver tumor progression and largely dampened RFA-induced tumor suppression. Notably, transfer of CD169⁺ macrophages synergistically enhanced RFA-induced inhibition of distant tumor. To our knowledge, this is the first study which demonstrates hepatic CD169⁺ macrophages as a key factor responsible for RFA-induced abscopal effect. Our data suggest RFA with transfer of CD169⁺ macrophages as a promising combination therapy to lessen metastasis or recurrence of liver cancer in patients.