Shed antigen-induced blocking effect on CAR-T cells targeting Glypican-3 in Hepatocellular Carcinoma

Role of cell-based therapies in digestive disorders: Obstacles and opportunities

Stem cell-based therapies have emerged as a promising frontier in the treatment of gastrointestinal disorders, offering potential solutions for challenges posed by conventional treatments. This review comprehensively examines recent advancements in cell-based therapeutic strategies, particularly focusing on stem cell applications, immunotherapy, and cellular therapies for digestive diseases. It highlights the successful differentiation of enteric neural progenitors from pluripotent stem cells and their application in animal models, such as Hirschsprung disease. Furthermore, the review evaluates clinical trials and experimental studies demonstrating the potential of stem cells in regenerating damaged tissues, modulating immune responses, and promoting healing in conditions like Crohn's disease and liver failure. By addressing challenges, such as scalability, immunogenicity, and ethical considerations, the review underscores the translational opportunities and obstacles in realizing the clinical potential of these therapies. Concluding with an emphasis on future directions, the study provides insights into optimizing therapeutic efficacy and fostering innovations in personalized medicine for digestive disorders.

Engineered E. coli OMVs Carrying the Membrane-Binding hGC33 Fragment Precisely Target Liver Cancer and Effectively Treat Tumor

Background

Glypican-3 (GPC3), which is a membrane-associated antigen that is overexpressed in hepatocellular carcinoma (HCC). hGC33, a humanized anti-GPC3 antibody, has been validated as a potential antibody drug with good antitumor activity by preclinical studies and the Phase II clinical trial. However, free drug usually lack good tumor penetration. Outer membrane vesicles (OMVs) that are secreted by Escherichia coli function as natural vectors for molecule delivery and mediators of biological signals across tissues. Our study aimed to engineer E. coli for use as a platform to precisely deliver the hGC33 single-chain variable fragment (hGC33-scFv) for the targeted treatment of HCC.

Methods

In this study, we utilized E. coli BL21(DE3) to express Hbp-hGC33-scFv fusion protein and generated E. coli hGC33-OMVs. After isolation and characterization, we assessed their chemotaxis toward HepG2  cells by Transwell, coimmunoprecipitation (co-IP) to confirm hGC33-GPC3 binding, and immunofluorescence (IF) to evaluate the localization of hGC33 on OMV membranes. The in vivo efficacy was assessed in BALB/c nude mice harboring HepG2  cell-derived xenografts, and tumor targeting was analyzed with Cy7-labeled OMVs and live imaging. Proliferation assays, cell cycle analysis, and Wnt pathway expression analysis were performed to elucidate the underlying mechanisms.

Results

hGC33-OMVs exhibited spherical bilayered nanostructures and displayed hGC33-scFv on their surface. hGC33-OMVs preferentially accumulated in tumors, significantly reducing tumor volume compared with controls and downregulating the proliferation markers Ki67 and PCNA. Transwell assays revealed increased tropism of hGC33-OMVs toward HepG2 cells, while Co-IP confirmed the direct interaction between hGC33 and GPC3. Meanwhile, hGC33-OMVs suppressed HepG2 cell proliferation, induced G1-phase arrest, and reduced Wnt3a, β-catenin, Cyclin D1, and C-myc expression.

Conclusion

Engineered E. coli hGC33-OMVs effectively target HCC via the hGC33-GPC3 interaction, inhibit tumor growth by suppressing Wnt signaling, and demonstrate potential for use as a versatile platform for antibody delivery.

Sex disparities in hepatocellular carcinoma immunotherapy: hormonal and genetic influences on treatment efficacy

Hepatocellular carcinoma (HCC) is a highly aggressive liver cancer with a rising incidence globally. Immunotherapy, particularly immune checkpoint inhibitors (ICIs), has revolutionized HCC treatment, yet response rates remain variable. Sex-based disparities in immunotherapy efficacy have become increasingly recognized as important factors influencing treatment outcomes in HCC. This review examines the role of biological sex in HCC progression and immunotherapy responses. It discusses the epidemiology of sex differences in HCC incidence, prognosis, and therapeutic outcomes, highlighting the impact of sex hormones, such as estrogen and testosterone, on immune system function and tumor biology. Estrogen's protective effects, including enhanced T cell activation and improved immune surveillance, contribute to better treatment responses in females, while testosterone's immunosuppressive effects lead to poorer outcomes in males. The review also explores the influence of the tumor microenvironment, including immune cell composition and macrophage polarization, on treatment efficacy. Emerging evidence suggests that sex-specific factors, including hormonal status, should be considered in clinical trials and personalized treatment strategies. By addressing these disparities, tailored immunotherapeutic approaches could optimize efficacy and minimize toxicity in both male and female HCC patients, ultimately improving overall outcomes.

Development and optimization of Eva1 (MPZL2) targeting chimeric antigen receptor T cells

BACKGROUND

Whereas chimeric antigen receptor gene modified T (CAR-T) cell therapy has been clinically applied to malignant lymphomas and multiple myeloma, CAR-T cell therapy for solid tumors has so far not reached clinical application. Epithelial V-like antigen 1 (Eva1), transcribed from myelin protein zero-like 2 (MPZL2), is a small surface protein highly expressed on various tumor cells. We selected Eva1 as a novel solid tumor-target antigen because of its broad expression across various tumor types. The purpose of the present study is to develop and optimize CAR-T cells targeting Eva1.

METHOD

We prepared various humanized single chain variable fragment sequences based on a mouse anti-human Eva1 monoclonal antibody. We constructed six humanized Eva1CAR-Ts and selected one that maintained specificity and good cellular proliferation after antigen stimulation. We further optimized the length of the extracellular spacer domain and the choice of the intracellular domain in vitro and in two different xenograft mouse models.

RESULTS

We confirmed Eva1 expression on various tumor cell lines by flow cytometry and analysis of public database, but we also observed that normal monocytes weakly expressed Eva1. A combination of short spacer domain and 4-1BB or CD79A/CD40 intracellular domain provided higher treatment efficacy both in vitro and in vivo. The cytokine release on autologous monocyte stimulation to Eva1CAR-T cells was comparable to that on autologous B cell stimulation to CD19CAR-T cells. Humanized Eva1CAR-T cells demonstrated excellent therapeutic efficacy by infusing a single dose of Eva1CAR-T cells (1×106) in both NCI-H1975 lung cancer and CFPAC-1 pancreatic cancer cell line grafted model.

CONCLUSIONS

In summary, these data suggest that humanized Eva1CAR-T has promising therapeutic potential for the treatment of various Eva1-positive solid tumors. Regarding on-target/off-tumor recognition, further detailed analyses of the Eva1CAR-T cell responses to normal tissues are needed.

SynNotch CAR-T cell, when synthetic biology and immunology meet again

Cancer immunotherapy has been transformed by chimeric antigen receptor (CAR) T-cell treatment, which has shown groundbreaking results in hematological malignancies. However, its application in solid tumors remains a formidable challenge due to immune evasion, tumor heterogeneity, and safety concerns arising from off-target effects. A long-standing effort in this field has been the development of synthetic receptors to create new signaling pathways and rewire immune cells for the specific targeting of cancer cells, particularly in cell-based immunotherapy. This field has undergone a paradigm shift with the introduction of synthetic Notch (synNotch) receptors, which offer a highly versatile signaling platform modeled after natural receptor-ligand interactions. By functioning as molecular logic gates, synNotch receptors enable precise, multi-antigen regulation of T-cell activation, paving the way for enhanced specificity and control. This review explores the revolutionary integration of synNotch systems with CAR T-cell therapy, emphasizing cutting-edge strategies to overcome the inherent limitations of traditional approaches. We delve into the mechanisms of synNotch receptor design, focusing on their ability to discriminate between cancerous and normal cells through spatiotemporally controlled gene expression. Additionally, we highlight recent advancements to improve therapeutic efficacy, safety, and adaptability in treating solid tumors. This study highlights the potential of synNotch-based CAR-T cells to transform the field of targeted cancer therapy by resolving present challenges and shedding light on potential future paths.

Allosteric targeted drug delivery for enhanced blood-brain barrier penetration via mimicking transmembrane domain interactions

Current strategies for active targeting in the brain are entirely based on the effective interaction of the ligand with the orthosteric sites of specific receptors on the blood-brain barrier (BBB), which is highly susceptible to various pathophysiological factors and limits the efficacy of drug delivery. Here, we propose an allosteric targeted drug delivery strategy that targets classical BBB transmembrane receptors by designing peptide ligands that specifically bind to their transmembrane domains. This strategy prevents competitive interference from endogenous ligands and antibodies by using the insulin receptor and integrin αv as model targets, respectively, and can effectively overcome pseudotargets or target loss caused by shedding or mutating the extracellular domain of target receptors. Moreover, these ligands can be spontaneously embedded in the phospholipid layer of lipid carriers using a plug-and-play approach without chemical modification, with excellent tunability and immunocompatibility. Overall, this allosteric targeted drug delivery strategy can be applied to multiple receptor targets and drug carriers and offers promising therapeutic benefits in brain diseases.

Application and prospect analysis of chimeric antigen receptor T-cell therapy in hepatocellular carcinoma treatment: a systematic review and meta-analysis

Introduction

Hepatocellular carcinoma (HCC), accounting for 90% of primary liver cancers, is a high-mortality malignancy and the third leading cause of cancer-related deaths globally, with major risk factors like hepatitis B/C, aflatoxin exposure, and obesity. Most patients are diagnosed at advanced stages, with a 5-year survival rate below 10%. Therefore, HCC treatment and research still face significant challenges, and more effective treatments need to be further explored.

Methods

We searched PubMed, Scopus, Web of Science and Embase from the time of repository construction to March 1, 2025, preliminary included studies involving animal experiments on the therapeutic effects of Chimeric Antigen Receptor T-cell (CAR-T cell) therapy on HCC. After exclusion and evaluation of literature, the random/fixed effects model was employed to perform meta-analysis and obtain Weighted Mean Difference (WMD) and 95% confidence interval (CI) of tumor volume and mass. We then verify the robustness of the results through subgroup analysis and sensitivity analysis. Use Q-test to evaluate heterogeneity and quantify it based on I² value.

Results

We included a total of 16 studies. Multiple independent sets of data were extracted from the experiments of these studies, of which 25 were used for volume-based meta-analysis and 16 were used for mass-based meta-analysis. Regarding volume, The combined mean CAR-T treatment group/control group resulted in an WMD of -515.77 (95% CI: -634.78 to -396.76; I² =90.8%). Meanwhile, based on mass, the combined mean CAR-T treatment group/control group resulted in an WMD of -0.30 (95% CI: -0.38 to -0.22; I² = 94.4%). The results of the bias analysis further validated the reliability of the research conclusions.

Conclusions

Based on the dual-index meta-analysis, the CAR-T therapy have been proved to possess significant therapeutic effect in HCC. However, the funnel plot of tumor mass and the Egger's regression suggest the potential presence of publication bias. Thus, it warrants further research to evaluate the potential of CAR-T therapy alone or as an adjuvant for HCC treatment.

Targeting the tumour cell surface in advanced prostate cancer

Prostate cancer remains a substantial health challenge, with >375,000 annual deaths amongst men worldwide. Most prostate cancer-related deaths are attributable to the development of resistance to standard-of-care treatments. Characterization of the diverse and complex surfaceome of treatment-resistant prostate cancer, combined with advances in drug development that leverage cell-surface proteins to enhance drug delivery or activate the immune system, have provided novel therapeutic opportunities to target advanced prostate cancer. The prostate cancer surfaceome, including proteins such as prostate-specific membrane antigen (PSMA), B7-H3, six transmembrane epithelial antigen of the prostate 1 (STEAP1), delta-like ligand 3 (DLL3), trophoblastic cell-surface antigen 2 (TROP2), prostate stem cell antigen (PSCA), HER3, CD46 and CD36, can be exploited as therapeutic targets, as regulatory mechanisms might contribute to the heterogeneity of expression of these proteins and subsequently affect treatment response and resistance. Specific treatment strategies targeting the surfaceome are in clinical development, including radionuclides, antibody-drug conjugates, T cell engagers and chimeric antigen receptor (CAR) T cells. Ultimately, biomarker development and clinical implementation of these agents will be informed and refined by further understanding of the biology of various targets; the target specificity and sensitivity of different agents; and off-target and toxic effects associated with these agents. Understanding the dynamic nature of cell-surface targets and non-overlapping expression patterns might also lead to future combinational strategies.

From molecular design to clinical translation: dual-targeted CAR-T strategies in cancer immunotherapy

The pathogenesis of tumors involves various abnormalities at both the cellular and genetic levels. Chimeric antigen receptor (CAR)-T cell immunotherapy has emerged as a transformative treatment strategy that effectively addresses these challenges. While CAR-T therapy has shown remarkable success in treating hematological malignancies, limitations have been identified, particularly in single antigen-targeting CAR-T therapies. These limitations include antigenic mutation or loss, reduced efficacy against leukemia, and poor results in solid tumors due to factors like low CAR-T cell persistence, limited tumor infiltration, rapid cell exhaustion, the suppressive tumor microenvironment, and heterogeneous tumor antigen expression. In recent years, multi-antigen targeted CAR-T therapies have garnered significant attention for their potential to prevent tumor relapse and progression. This review outlines the fundamental design of dual CAR structures and summarizes the major advancements in both preclinical studies and clinical trials of dual-targeted CAR-T cell therapy, categorized by cancer type. Additionally, it discusses the challenges associated with dual-targeted CAR-T therapy and the strategies to enhance its efficacy and applicability in treating both hematologic and solid tumors. In conclusion, the progress in dual-targeted CAR-T cell therapy presents a promising therapeutic avenue for multiple malignancies, offering insights into future modifications of immunotherapy to advance the field.

T lymphocyte-based immune response and therapy in hepatocellular carcinoma: focus on TILs and CAR-T cells

Hepatocellular carcinoma (HCC) is among the leading causes of cancer-related death worldwide. The primary therapies for HCC are liver transplantation, hepatic tumor excision, radiofrequency ablation, and molecular-targeted medicines. An unfavorable prognosis marks HCC and has limited pharmacological response in therapeutic studies. The tumor immune microenvironment (TME) imposes significant selection pressure on HCC, resulting in its evolution and recurrence after various treatments. As the principal cellular constituents of tumor-infiltrating lymphocytes (TILs), T cells have shown both anti-tumor and protumor actions in HCC. T cell-mediated immune responses are pivotal in cancer monitoring and elimination. TILs are recognized for their critical involvement in the progression, prognosis, and immunotherapeutic management of HCC. Foxp3 + , CD8 + , CD3 + , and CD4 + T cells are the extensively researched subtypes of TILs. This article examines the functions and processes of several subtypes of TILs in HCC. Emerging T cell-based therapies, including TILs and chimeric antigen receptor (CAR)-T cell therapy, have shown tumor regression in several clinical and preclinical studies. Herein, it also delves into the existing T cell-based immunotherapies in HCC, with emphasis on TILs and CAR-T cells.

Heparan sulfate chains in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) corresponds to the vast majority of liver cancer cases, with one of the highest mortality rates. Major advances have been made in this field both in the characterization of the molecular pathogenesis and in the development of systemic therapies. Despite these achievements, biomarkers and more efficient treatments are still needed to improve its management. Heparan sulfate (HS) chains are polysaccharides that are present at the cell surface or in the extracellular matrix that are able to bind various types of molecules, such as soluble factors, affecting their availability and thus their effects, or to contribute to interactions that position cells in their environments. Enzymes can modify HS chains after their synthesis, thus changing their properties. Numerous studies have shown HS-related proteins to be key actors that are associated with cellular effects, such as tumor growth, invasion, and metastasis, including in the context of liver carcinogenesis. The aim of this review is to provide a comprehensive overview of the biology of HS chains and their potential importance in HCC, from biological considerations to clinical development, and the identification of biomarkers, as well as therapeutic perspectives.

CAR-T Cell Manufacturing for Hematological and Solid Tumors: From the Preclinical to Clinical Point of View

Cell therapy based on chimeric antigen receptor (CAR) T cells has represented a revolutionary new approach for treating tumors, especially hematological diseases. Complete remission rates (CRR) > 80%-97% and 50%-90% overall response rates (ORR) have been achieved with a treatment based on CAR-T cells in patients with malignant B-cell tumors that have relapsed or are refractory to previous treatments. Toxicity remains the major problem. Most patients treated with CAR-T cells develop high-grade cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). However, the unprecedentedly high CRR and ORR have led to the approval of six CAR-T cell therapeutics by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA), prompting researchers to improve existing products and develop new ones. By now, around 1000 clinical trials based on CAR-T cells are registered at ClinicalTrials.gov: 82% are for hematological diseases, while the remaining 16% are for solid tumors. As a result of this increased research, an enormous amount of conflicting information has been accumulated in the literature, and each group follows its manufacturing protocols and performs specific in vitro testing. This review aimed to combine and compare clinical and preclinical information, highlighting the most used protocols to provide a comprehensive overview of the in vitro world of CAR-T cells, from manufacturing to their characterization. The focus is on all steps of the CAR-T cell manufacturing process, from the collection of patient or donor blood to the enrichment of T cells, their activation with anti-CD3/CD28 beads, interleukin-2 (IL-2) or IL-7 and IL-15 (induction of a more functional memory phenotype), and their transfection (viral or non-viral methods). Automation is crucial for ensuring a standardized final product.

Unlocking the potential of chimeric antigen receptor T cell engineering immunotherapy: Long road to achieve precise targeted therapy for hepatobiliary pancreatic cancers

Innovative therapeutic strategies are urgently needed to address the ongoing global health concern of hepatobiliary pancreatic malignancies. This review summarizes the latest and most comprehensive research of chimeric antigen receptor (CAR-T) cell engineering immunotherapy for treating hepatobiliary pancreatic cancers. Commencing with an exploration of the distinct anatomical location and the immunosuppressive, hypoxic tumor microenvironment (TME), this review critically assesses the limitations of current CAR-T therapy in hepatobiliary pancreatic cancers and proposes corresponding solutions. Various studies aim at enhancing CAR-T cell efficacy in these cancers through improving T cell persistence, enhancing antigen specificity and reducing tumor heterogeneity, also modulating the immunosuppressive and hypoxic TME. Additionally, the review examines the application of emerging nanoparticles and biotechnologies utilized in CAR-T therapy for these cancers. The results suggest that constructing optimized CAR-T cells to overcome physical barrier, manipulating the TME to relieve immunosuppression and hypoxia, designing CAR-T combination therapies, and selecting the most suitable delivery strategies, all together could collectively enhance the safety of CAR-T engineering and advance the effectiveness of adaptive cell therapy for hepatobiliary pancreatic cancers.

Dual-Functional Nanobody Optical Probes for In Vivo Fluorescence Imaging and Photodynamic Therapy

Nanobodies have gained significant attention as promising tools for cancer diagnostics and treatment due to their unique ability to precisely target specific cancer cells. However, a major challenge lies in the site-specific incorporation of multifunctional molecules into nanobodies, as it is essential to link these molecules in a manner that preserves the nanobody's function and stability while retaining the desired therapeutic or diagnostic properties. This study outlines the development of dual-functional nanobody optical probes for enhanced cancer diagnostics and therapeutic interventions. We designed a dual-functional clickable linker that enables site-specific functionalization of the nanobody, facilitating the simultaneous conjugation of two dyes: indocyanine green for imaging and chlorin e6 for photodynamic therapy. In vitro cellular assays confirmed the successful labeling of the dual-functional dyes, with the nanobody probe exhibiting high cellular binding specificity. In vivo imaging of mice bearing Hep3B tumors revealed clear visualization with a high signal-to-noise ratio. Furthermore, PEGylated probes significantly improved tumor retention, enhancing both imaging contrast and photodynamic therapy efficacy as compared to free chlorin e6. These dual-functional nanobody probes show great promise for the precise diagnosis and treatment of malignant tumors.

Hamid SS. Multiomics in silico analysis identifies TM4SF4 as a cell surface target in hepatocellular carcinoma

The clinical application of cellular immunotherapy in hepatocellular carcinoma (HCC) is impeded by the lack of a cell surface target frequently expressed in HCC cells and with minimal presence in normal tissues to reduce on-target, off-tumor toxicity. To address this, an in silico multomics analysis was conducted to identify an optimal therapeutic target in HCC. A longlist of genes (n = 12,948) expressed in HCCs according to The Human Protein Atlas database were examined. Eight genes were shortlisted to identify one with the highest expression in HCCs, without being shed into circulation, and with restrictive expression profile in other normal human tissues. A total of eight genes were shortlisted and subsequently ranked according to the combination of their transcript and protein expression levels in HCC cases (n = 791) derived from four independent datasets. TM4SF4 was the top-ranked target with the highest expression in HCCs. TM4SF4 showed more favorable expression profile with significantly lower expression in normal human tissues but more highly expressed in HCC compared with seven other common HCC therapeutic targets. Furthermore, scRNA-seq and immunohistochemistry datasets showed that TM4SF4 was absent in immune cell populations but highly expressed in the bile duct canaliculi of hepatocytes, regions inaccessible to immune cells. In scRNA-seq dataset of HCCs, TM4SF4 expression was positively associated with mitochondrial components and oxidative phosphorylation Gene Ontologies in HCC cells (n = 15,787 cells), suggesting its potential roles in mitochondrial-mediated oncogenic effects in HCC. Taken together, TM4SF4 is proposed as a promising cell surface target in HCC due to its high expression in HCC cells with restricted expression profile in non-cancerous tissues, and association with HCC oncogenic pathways.

Mechanisms of antigen-dependent resistance to chimeric antigen receptor (CAR)-T cell therapies

Cancer immunotherapy has reshaped the landscape of cancer treatment over the past decades. Genetic manipulation of T cells to express synthetic receptors, known as chimeric antigen receptors (CAR), has led to the creation of tremendous commercial and therapeutic success for the treatment of certain hematologic malignancies. However, since the engagement of CAR-T cells with their respective antigens is solely what triggers their cytotoxic reactions against target cells, the slightest changes to the availability and/or structure of the target antigen often result in the incapacitation of CAR-T cells to enforce tumoricidal responses. This results in the resistance of tumor cells to a particular CAR-T cell therapy that requires meticulous heeding to sustain remissions in cancer patients. In this review, we highlight the antigen-dependent resistance mechanisms by which tumor cells dodge being recognized and targeted by CAR-T cells. Moreover, since substituting the target antigen is the most potent strategy for overcoming antigen-dependent disease relapse, we tend to highlight the current status of some target antigens that might be considered suitable alternatives to the currently available antigens in various cancers. We also propose target antigens whose targeting might reduce the off-tumor adverse events of CAR-T cells in certain malignancies.

Efficacy and safety of the combination of envafolimab and lenvatinib in unresectable hepatocellular carcinoma: a single-arm, multicentre, exploratory phase II clinical study

Currently, therapeutic combinations of immune checkpoint inhibitors (ICIs) with anti-angiogenic agents have shown promising outcomes and have the potential to establish a new standard of care. The efficacy and safety of the first-line combination of envafolimab (an ICI) and lenvatinib (an anti-tumor angiogenesis drug) for the treatment of patients with inoperable hepatocellular carcinoma (HCC) have not been demonstrated. Unresectable HCC patients with an Eastern Cooperative Oncology Group (ECOG) physical status score ≤ 1 and a Child-Pugh score ≤ 7 who had not received systemic therapy were included in this single-arm, exploratory, multicentre phase II clinical study. All patients were required to meet the criteria of being at least 18 years of age, having no history of other malignancies, and existing at least one measurable lesion. The patients were treated with envafolimab (150 mg, QW, subcutaneous) in combination with lenvatinib (12 mg for patients weighing over 60 kg, 8 mg for patients weighing under 60 kg). The co-primary endpoint of the study was overall survival (OS), while surrogate endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety. Between March 2022 and April 2023, 36 patients were enrolled, 30 of whom were treated with envafolimab plus lenvatinib. At data cutoff, the median follow-up duration was 20 months (95% CI 18.9-21.1). Among the 30 assessable patients (patients treated according to the trial protocol), the median overall survival (mOS) and median progression-free survival (mPFS) for the therapy comprising envafolimab alongside lenvatinib were 18.5 months (95% CI 13.2-23.8) and 9.4 months (95% CI 1.6-15.6), respectively. The ORR and the DCR (evaluated according to mRECIST criteria) reached 40% and 80%, respectively. In terms of safety, 23 patients (76.7%) experienced at least one treatment-related adverse event (TRAE), of which the most common was elevated aspartate aminotransferase (AST, 23.3%). Furthermore, grade 3 and higher TRAEs occurred in 30%. This study demonstrates that envafolimab in combination with lenvatinib exhibits favourable anti-cancer activity and a manageable safety profile for the first-line treatment of patients with unresectable HCC.

Heterogeneity of tumor-associated neutrophils in hepatocellular carcinoma

Neutrophils are the most abundant cell type in human blood and play a crucial role in the immune system and development of tumors. This review begins with the generation and development of neutrophils, traces their release from the bone marrow into the bloodstream, and finally discusses their role in the hepatocellular carcinoma (HCC) microenvironment. It elaborates in detail the mechanisms by which tumor-associated neutrophils (TANs) exert antitumor or protumor effects under the influence of various mediators in the tumor microenvironment. Neutrophils can exert antitumor effects through direct cytotoxic action. However, they can also accelerate the formation and progression of HCC by being recruited and infiltrated, promoting tumor angiogenesis, and maintaining an immunosuppressive microenvironment. Therefore, based on the heterogeneity and plasticity of neutrophils in tumor development, this review summarizes the current immunotherapies targeting TANs, discusses potential opportunities and challenges, and provides new insights into exploring more promising strategies for treating HCC.

Rapid evaluation of hepatocellular carcinoma by detecting plasma exosomes with time-resolved fluorescence immunochromatographic test strips

Time-resolved fluorescence immunochromatographic test strips (TRFIS) was developed for the rapid detection of hepatocellular carcinoma (HCC)-specific plasma exosomes (hExos) by targeting the hExo-surface membrane protein glypican-3 (GPC3). The GPC3-TRFIS could directly detect plasma exosomes without the isolation and purification process, and the whole immunoassay could be completed within 15 min. The visual detection limit of GPC3-TRFIS was 3.44 × 10^9 particles/mL, with a minimum detection limit of 1.8 × 10^9 particles/mL. For analysis of the clinical HCC samples, GPC3-TRFIS shows high specificity for detection of hExo, and was nearly unreactive for healthy donors' samples. GPC3-TRFIS was able to efficiently distinguish HCC patients (19 cases) from healthy donors (19 cases). Overall, the developed TRFIS offers the benefits of high sensitivity, simple operation, and no need of large precision instruments and professional technical personnel for rapid detection of plasma hExos, and supplies a novel approach for early screening of HCC.

Novel CAR-T cells targeting TRKB for the treatment of solid cancer

Chimeric antigen receptor (CAR) T-cell therapy is highly effective for treating blood cancers such as B-cell malignancies, however, its effectiveness as an approach to treat solid tumors remains to be further explored. Here, we focused on the development of CAR-T cell therapies targeting tropomyosin-related kinase receptor B (TRKB), a highly expressed protein that is significantly associated with tumor progression, malignancy, and drug resistance in multiple forms of aggressive solid tumors. To achieve this, we screened brain-derived neurotrophic factor (BDNF) and neurotrophin 4 (NTF4) ligand-based CAR-T cells for their efficiency in targeting the TRKB receptor in the context of solid tumors, particularly hepatocellular carcinoma and pancreatic cancer. We demonstrated that TRKB is overexpressed not only in hepatocellular carcinoma and pancreatic carcinoma cell lines but also in cancer stem-like cells (CSCs). Notably, BDNF-CAR T and NTF4-CAR T cells could not only effectively target and kill TRKB-expressing pan-cancer cell lines in a dose-dependent manner but also effectively kill CSCs. We also performed in vivo studies to show that NTF4-CAR T cells have a better potential to inhibit the tumor growth of hepatocellular carcinoma xenografts in mice, compared with BDNF-CAR T cells. Taken together, our findings suggest that CAR-T targeting TRKB may be a promising approach for developing novel therapies to treat solid cancers.

CAR-T cell therapy for hepatocellular carcinoma: current trends and challenges

Hepatocellular carcinoma (HCC) ranks among the most prevalent cancers worldwide, highlighting the urgent need for improved diagnostic and therapeutic methodologies. The standard treatment regimen generally involves surgical intervention followed by systemic therapies; however, the median survival rates for patients remain unsatisfactory. Chimeric antigen receptor (CAR) T-cell therapy has emerged as a pivotal advancement in cancer treatment. Both clinical and preclinical studies emphasize the notable efficacy of CAR T cells in targeting HCC. Various molecules, such as GPC3, c-Met, and NKG2D, show significant promise as potential immunotherapeutic targets in liver cancer. Despite this, employing CAR T cells to treat solid tumors like HCC poses considerable challenges within the discipline. Numerous innovations have significant potential to enhance the efficacy of CAR T-cell therapy for HCC, including improvements in T cell trafficking, strategies to counteract the immunosuppressive tumor microenvironment, and enhanced safety protocols. Ongoing efforts to discover therapeutic targets for CAR T cells highlight the need for the development of more practical manufacturing strategies for CAR-modified cells. This review synthesizes recent findings and clinical advancements in the use of CAR T-cell therapies for HCC treatment. We elucidate the therapeutic benefits of CAR T cells in HCC and identify the primary barriers to their broader application. Our analysis aims to provide a comprehensive overview of the current status and future prospects of CAR T-cell immunotherapy for HCC.

Liver resection and transplantation in the era of checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) have revolutionised the treatment landscape for advanced hepatocellular carcinoma (HCC). The combination of atezolizumab and bevacizumab has demonstrated efficacy, establishing a new standard of care for advanced HCC. Neoadjuvant studies have shown promising results with high response rates, increasing research into ICIs' role. In the peri-operative setting, in addition to adjuvant and neo-adjuvant therapies, strategies for "downstaging" and "bridging" patients to liver transplantation (LT) are being investigated, broadening the eligible candidate pool. Furthermore, therapeutic advances have reshaped conversion strategies for hepatic resection, with emerging evidence indicating a role for adjuvant immunotherapy in patients at high risk of postoperative recurrence. In LT, concerns have arisen over the potential conflict between immunosuppression needs and the immune-enhancing effects of ICIs, with reports of severe rejection. However, liver-specific factors may lessen rejection risks, prompting exploration into the safety of pre-transplant ICI administration. Moreover, ongoing trials must prioritise patient selection and vigilant management protocols. Despite the remarkable progress in immunotherapy, the intricate molecular interactions within the tumour microenvironment and their implications on oncogenic pathways remain incompletely understood. This highlights the need for specialised expertise to effectively integrate immunotherapy into the surgical management of HCC. Key challenges include ensuring safety, optimising oncological outcomes, managing the risk of graft rejection in transplant recipients, and refining patient selection criteria. In this review, we aim to provide a comprehensive overview of the evolving role of immunotherapy in the surgical management of HCC, discussing the rationale for its application in both pre- and post-surgical contexts, leveraging current clinical experience, identifying potential limitations, and envisioning future applications. By integrating existing knowledge and highlighting areas for further investigation, this review seeks to inform clinical practice and guide future research endeavours.

Advances in immunotherapy for hepatitis B virus associated hepatocellular carcinoma patients

Hepatitis B virus (HBV) infection plays an important role in the occurrence and development of hepatocellular carcinoma (HCC), and the rate of HBV infection in liver cancer patients in China is as high as 92.05%. Due to long-term exposure to chronic antigens from the gut, the liver needs to maintain a certain level of immune tolerance, both to avoid severe inflammation caused by non-pathogenic antigens and to maintain the possibility of rapid and violent responses to infection and tumors. Therefore, HBV infection interacts with the tumor microenvironment (TME) through a highly complex and intertwined signaling pathway, which results in a special TME in HCC. Due to changes in the TME, tumor cells can evade immune surveillance by inhibiting tumor-specific T cell function through cytotoxic T-lymphocy-associated protein-4 (CTLA-4) and programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1). Interferons, as a class of immune factors with strong biological activity, can improve the TME of HBV-HCC through various pathways. In recent years, the systematic treatment of HCC has gradually come out of the dilemma. In addition to the continuous emergence of new multi-target anti-vascular tyrosine kinase inhibitor drugs, immune checkpoint inhibitors have opened up a new avenue for the systematic treatment of HCC. At present, immunotherapy based on PD-1/L1 inhibitors has gradually become a new direction of systematic treatment for HCC, and the disease characteristics of patients included in global clinical studies are different from those of Chinese patients. Therefore, whether a group of HCC patients with HBV background and poor prognosis in China can also benefit from immunotherapy is an issue of wide concern. This review aims to elucidate the advances of immunotherapy for HBV related HCC patients with regard to: (1) Immunotherapy based on interferons; (2) Immunotherapy based on PD-1/L1 inhibitors; (3) Immunotherapy based on CTLA4 inhibitors; (4) Adoptive cell transfer; (5) Combination immunotherapy strategy; and (6) Shortcomings of immunotherapy.

Advances in immunotherapy for hepatitis B virus associated hepatocellular carcinoma patients

Hepatitis B virus (HBV) infection plays an important role in the occurrence and development of hepatocellular carcinoma (HCC), and the rate of HBV infection in liver cancer patients in China is as high as 92.05%. Due to long-term exposure to chronic antigens from the gut, the liver needs to maintain a certain level of immune tolerance, both to avoid severe inflammation caused by non-pathogenic antigens and to maintain the possibility of rapid and violent responses to infection and tumors. Therefore, HBV infection interacts with the tumor microenvironment (TME) through a highly complex and intertwined signaling pathway, which results in a special TME in HCC. Due to changes in the TME, tumor cells can evade immune surveillance by inhibiting tumor-specific T cell function through cytotoxic T-lymphocy-associated protein-4 (CTLA-4) and programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1). Interferons, as a class of immune factors with strong biological activity, can improve the TME of HBV-HCC through various pathways. In recent years, the systematic treatment of HCC has gradually come out of the dilemma. In addition to the continuous emergence of new multi-target anti-vascular tyrosine kinase inhibitor drugs, immune checkpoint inhibitors have opened up a new avenue for the systematic treatment of HCC. At present, immunotherapy based on PD-1/L1 inhibitors has gradually become a new direction of systematic treatment for HCC, and the disease characteristics of patients included in global clinical studies are different from those of Chinese patients. Therefore, whether a group of HCC patients with HBV background and poor prognosis in China can also benefit from immunotherapy is an issue of wide concern. This review aims to elucidate the advances of immunotherapy for HBV related HCC patients with regard to: (1) Immunotherapy based on interferons; (2) Immunotherapy based on PD-1/L1 inhibitors; (3) Immunotherapy based on CTLA4 inhibitors; (4) Adoptive cell transfer; (5) Combination immunotherapy strategy; and (6) Shortcomings of immunotherapy.

Progress and challenges in glypican-3 targeting for hepatocellular carcinoma therapy

INTRODUCTION

Glypican-3 (GPC3) is a cell membrane-anchored heparan sulfate proteoglycan that has recently garnered attention as a cancer antigen owing to its high expression in numerous cancers, particularly hepatocellular carcinoma (HCC), and to limited expression in adult normal tissue.

AREAS COVERED

Here, we propose the potential of GPC3 as a cancer antigen based on our experience with the GPC3 peptide vaccine against HCC, having developed a vaccine that progressed from preclinical studies to first-in-human clinical trials. In this review, we present a summary of the current status and future prospects of immunotherapies targeting GPC3 by focusing on clinical trials; peptide vaccines, mRNA vaccines, antibody therapy, and chimeric antigen receptor/T-cell receptor - T-cell therapy and discuss additional strategies for effectively eliminating HCC through immunotherapy.

EXPERT OPINION

GPC3 is an ideal cancer antigen for HCC immunotherapy. In resectable HCC, immunotherapies that leverage physiological immune surveillance, immune checkpoint inhibitors, and GPC3-target cancer vaccines appear promising in preventing recurrence and could be considered as a prophylactic adjuvant therapy. However, in advanced HCC, clinical trials have not demonstrated sufficient anti-tumor efficacy, in contrast with preclinical studies. Reverse translation, bedside-to-bench research, is crucial to identify the factors that have hindered GPC3 target immunotherapies.

Immunotherapy in liver cancer: overcoming the tolerogenic liver microenvironment

Liver cancer is a major global health concern, ranking among the top causes of cancer-related deaths worldwide. Despite advances in medical research, the prognosis for liver cancer remains poor, largely due to the inherent limitations of current therapies. Traditional treatments like surgery, radiation, and chemotherapy often fail to provide long-term remission and are associated with significant side effects. Immunotherapy has emerged as a promising avenue for cancer treatment, leveraging the body's immune system to target and destroy cancer cells. However, its application in liver cancer has been limited. One of the primary challenges is the liver's unique immune microenvironment, which can inhibit the effectiveness of immunotherapeutic agents. This immune microenvironment creates a barrier, leading to drug resistance and reducing the overall efficacy of treatment. Recent studies have focused on understanding the immunological landscape of liver cancer to develop strategies that can overcome these obstacles. By identifying the specific factors within the liver that contribute to immune suppression and drug resistance, researchers aim to enhance the effectiveness of immunotherapy. Prospective strategies include combining immunotherapy with other treatments, using targeted therapies to modulate the immune microenvironment, and developing new agents that can bypass or counteract the inhibitory mechanisms in the liver. These advancements hold promise for improving outcomes in liver cancer treatment.

Finding Your CAR: The Road Ahead for Engineered T Cells

Adoptive cellular therapy using chimeric antigen receptors (CARs) has transformed immunotherapy by engineering T cells to target specific antigens on tumor cells. As the field continues to advance, pathology laboratories will play increasingly essential roles in the complicated multi-step process of CAR T-cell therapy. These include detection of targetable tumor antigens by flow cytometry or immunohistochemistry at the time of disease diagnosis and the isolation and infusion of CAR T cells. Additional roles include: i) detecting antigen loss or heterogeneity that renders resistance to CAR T cells as well as identifying alternative targetable antigens on tumor cells, ii) monitoring the phenotype, persistence, and tumor infiltration properties of CAR T cells and the tumor microenvironment for factors that predict CAR T-cell therapy success, and iii) evaluating side effects and biomarkers of CAR T-cell cytotoxicity such as cytokine release syndrome. This review highlights existing technologies that are applicable to monitoring CAR T-cell persistence, target antigen identification, and loss. Also discussed are emerging technologies that address new challenges such as how to put a brake on CAR T cells. Although pathology laboratories have already provided companion diagnostic tests important in immunotherapy (eg, programmed death-ligand 1, microsatellite instability, and human epidermal growth factor receptor 2 testing), it draws attention to the exciting new translational research opportunities in adoptive cellular therapy.

The association between tumour heterogeneity and immune evasion mechanisms in hepatocellular carcinoma and its clinical implications

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. The emergence of combination therapy, atezolizumab (anti-PDL1, immune checkpoint inhibitor) and bevacizumab (anti-VEGF) has revolutionised the management of HCC. Despite this breakthrough, the best overall response rate with first-line systemic therapy is only about 30%, owing to intra-tumoural heterogeneity, complex tumour microenvironment and the lack of predictive biomarkers. Many groups have attempted to classify HCC based on the immune microenvironment and have consistently observed better outcomes in immunologically "hot" HCC. We summarised possible mechanisms of tumour immune evasion based on the latest literature and the rationale for combination/sequential therapy to improve treatment response. Lastly, we proposed future strategies and therapies to overcome HCC immune evasion to further improve treatment outcomes of HCC.

Glypican-3 deficiency in liver cancer upregulates MAPK/ERK pathway but decreases cell proliferation

Glypican-3 (GPC3) is overexpressed in hepatocellular carcinomas and hepatoblastomas and represents an important therapeutic target but the biologic importance of GPC3 in liver cancer is unclear. To date, there are limited data characterizing the biological implications of GPC3 knockout (KO) in liver cancers that intrinsically express this target. Here, we report on the development and characterization of GPC3-KO liver cancer cell lines and compare to them to parental lines. GPC3-KO variants were established in HepG2 and Hep3B liver cancer cell lines using a lentivirus-mediated CRISPR/Cas9 system. We assessed the effects of GPC3 deficiency on oncogenic properties in vitro and in murine xenograft models. Downstream cellular signaling pathway changes induced by GPC3 deficiency were examined by RNAseq and western blot. To confirm the usefulness of the models for GPC3-targeted drug development, we evaluated the target engagement of a GPC3-selective antibody, GC33, conjugated to the positron-emitting zirconium-89 (89Zr) in subcutaneous murine xenografts of wild type (WT) and KO liver cancer cell lines. Deletion of GPC3 significantly reduced liver cancer cell proliferation, migration, and invasion compared to the parental cell lines. Additionally, the tumor growth of GPC3-KO liver cancer xenografts was significantly slower compared with control xenografts. RNA sequencing analysis also showed GPC3-KO resulted in a reduction in the expression of genes associated with cell cycle regulation, invasion, and migration. Specifically, we observed the downregulation of components in the AKT/NFκB/WNT signaling pathways and of molecules related to cell cycle regulation with GPC3-KO. In contrast, pMAPK/ERK1/2 was upregulated, suggesting an adaptive compensatory response. KO lines demonstrated increased sensitivity to ERK (GDC09994), while AKT (MK2206) inhibition was more effective in WT lines. Using antibody-based positron emission tomography (immunoPET) imaging, we confirmed that 89Zr-GC33 accumulated exclusively in GPC3-expression xenografts but not in GPC3-KO xenografts with high tumor uptake and tumor-to-liver signal ratio. We show that GPC3-KO liver cancer cell lines exhibit decreased tumorigenicity and altered signaling pathways, including upregulated pMAPK/ERK1/2, compared to parental lines. Furthermore, we successfully distinguished between GPC3+ and GPC3- tumors using the GPC3-targeted immunoPET imaging agent, demonstrating the potential utility of these cell lines in facilitating GPC3-selective drug development.

Bispecific CAR-T cells targeting FAP and GPC3 have the potential to treat hepatocellular carcinoma

Chimeric antigen receptor (CAR) T cell therapy has demonstrated robust efficacy against hematological malignancies, but there are still some challenges regarding treating solid tumors, including tumor heterogeneity, antigen escape, and an immunosuppressive microenvironment. Here, we found that SNU398, a hepatocellular carcinoma (HCC) cell line, exhibited high expression levels of fibroblast activation protein (FAP) and Glypican 3 (GPC3), which were negatively correlated with patient prognosis. The HepG2 HCC cell line highly expressed GPC3, while the SNU387 cell line exhibited high expression of FAP. Thus, we developed bispecific CAR-T cells to simultaneously target FAP and GPC3 to address tumor heterogeneity in HCC. The anti-FAP-GPC3 bispecific CAR-T cells could recognize and be activated by FAP or GPC3 expressed by tumor cells. Compared with anti-FAP CAR-T cells or anti-GPC3 CAR-T cells, bispecific CAR-T cells achieved more robust activity against tumor cells expressing FAP and GPC3 in vitro. The anti-FAP-GPC3 bispecific CAR-T cells also exhibited superior antitumor efficacy and significantly prolonged the survival of mice compared with single-target CAR-T cells in vivo. Overall, the use of anti-FAP-GPC3 bispecific CAR-T cells is a promising treatment approach to reduce tumor recurrence caused by tumor antigen heterogeneity.

Universal CAR 2.0 to overcome current limitations in CAR therapy

Chimeric antigen receptor (CAR) T cell therapy has effectively complemented the treatment of advanced relapsed and refractory hematological cancers. The remarkable achievements of CD19- and BCMA-CAR T therapies have raised high expectations within the fields of hematology and oncology. These groundbreaking successes are propelling a collective aspiration to extend the reach of CAR therapies beyond B-lineage malignancies. Advanced CAR technologies have created a momentum to surmount the limitations of conventional CAR concepts. Most importantly, innovations that enable combinatorial targeting to address target antigen heterogeneity, using versatile adapter CAR concepts in conjunction with recent transformative next-generation CAR design, offer the promise to overcome both the bottleneck associated with CAR manufacturing and patient-individualized treatment regimens. In this comprehensive review, we delineate the fundamental prerequisites, navigate through pivotal challenges, and elucidate strategic approaches, all aimed at paving the way for the future establishment of multitargeted immunotherapies using universal CAR technologies.

A Review of CAR-T Combination Therapies for Treatment of Gynecological Cancers

CAR-T cell therapy offers a promising way for prolonged cancer remission, specifically in the case of blood cancers. However, its application in the treatment of solid tumors still faces many limitations. This review paper provides a comprehensive overview of the challenges and strategies associated with CAR-T cell therapy for solid tumors, with a focus on gynecological cancer. This study discusses the limitations of CAR-T therapy for solid tumor treatment, such as T cell exhaustion, stromal barrier, and antigen shedding. Additionally, it addresses possible approaches to increase CAR-T efficacy in solid tumors, including combination therapies with checkpoint inhibitors and chemotherapy, as well as the novel approach of combining CAR-T with oncolytic virotherapy. Given the lack of comprehensive research on CAR-T combination therapies for treating gynecological cancers, this review aims to provide insights into the current landscape of combination therapies for solid tumors and highlight the potential of such an approach in gynecology.

Expand available targets for CAR-T therapy to overcome tumor drug resistance based on the "Evolutionary Traps"

Based on the concept of "Evolutionary Traps", targeting survival essential genes obtained during tumor drug resistance can effectively eliminate resistant cells. While, it still faces limitations. In this study, lapatinib-resistant cells were used to test the concept of "Evolutionary Traps" and no suitable target stand out because of the identified genes without accessible drug. However, a membrane protein PDPN, which is low or non-expressed in normal tissues, is identified as highly expressed in lapatinib-resistant tumor cells. PDPN CAR-T cells were developed and showed high cytotoxicity against lapatinib-resistant tumor cells in vitro and in vivo, suggesting that CAR-T may be a feasible route for overcoming drug resistance of tumor based on "Evolutionary Trap". To test whether this concept is cell line or drug dependent, we analyzed 21 drug-resistant tumor cell expression profiles reveal that JAG1, GPC3, and L1CAM, which are suitable targets for CAR-T treatment, are significantly upregulated in various drug-resistant tumor cells. Our findings shed light on the feasibility of utilizing CAR-T therapy to treat drug-resistant tumors and broaden the concept of the "Evolutionary Trap".

Immunosuppressive tumor microenvironment and immunotherapy of hepatocellular carcinoma: current status and prospectives

Hepatocellular carcinoma (HCC) is a major health concern worldwide, with limited therapeutic options and poor prognosis. In recent years, immunotherapies such as immune checkpoint inhibitors (ICIs) have made great progress in the systemic treatment of HCC. The combination treatments based on ICIs have been the major trend in this area. Recently, dual immune checkpoint blockade with durvalumab plus tremelimumab has also emerged as an effective treatment for advanced HCC. However, the majority of HCC patients obtain limited benefits. Understanding the immunological rationale and exploring novel ways to improve the efficacy of immunotherapy has drawn much attention. In this review, we summarize the latest progress in this area, the ongoing clinical trials of immune-based combination therapies, as well as novel immunotherapy strategies such as chimeric antigen receptor T cells, personalized neoantigen vaccines, oncolytic viruses, and bispecific antibodies.

Treatment Options for Hepatocellular Carcinoma Using Immunotherapy: Present and Future

Hepatocellular carcinoma (HCC) is a common cancer, and the body's immune responses greatly affect its progression and the prognosis of patients. Immunological suppression and the maintenance of self-tolerance in the tumor microenvironment are essential responses, and these form part of the theoretical foundations of immunotherapy. In this review, we first discuss the tumor microenvironment of HCC, describe immunosuppression in HCC, and review the major biomarkers used to track HCC progression and response to treatment. We then examine antibody-based therapies, with a focus on immune checkpoint inhibitors (ICIs), monoclonal antibodies that target key proteins in the immune response (programmed cell death protein 1, anti-cytotoxic T-lymphocyte associated protein 4, and programmed death-ligand 1) which have transformed the treatment of HCC and other cancers. ICIs may be used alone or in conjunction with various targeted therapies for patients with advanced HCC who are receiving first-line treatments or subsequent treatments. We also discuss the use of different cellular immunotherapies, including T cell receptor (TCR) T cell therapy and chimeric antigen receptor (CAR) T cell therapy. We then review the use of HCC vaccines, adjuvant immunotherapy, and oncolytic virotherapy, and describe the goals of future research in the development of treatments for HCC.

Efficient CAR T cell targeting of the CA125 extracellular repeat domain of MUC16

BACKGROUND

Ovarian cancer (OC) is the leading cause of death from gynecologic malignancies in the Western world. Contributing factors include a high frequency of late-stage diagnosis, the development of chemoresistance, and the evasion of host immune responses. Currently, debulking surgery and platinum-based chemotherapy are the treatment cornerstones, although recurrence is common. As the clinical efficacy of immune checkpoint blockade is low, new immunotherapeutic strategies are needed. Chimeric antigen receptor (CAR) T cell therapy empowers patients' own T cells to fight and eradicate cancer, and has been tested against various targets in OC. A promising candidate is the MUC16 ectodomain. This ectodomain remains on the cell surface after cleavage of cancer antigen 125 (CA125), the domain distal from the membrane, which is currently used as a serum biomarker for OC. CA125 itself has not been tested as a possible CAR target. In this study, we examined the suitability of the CA125 as a target for CAR T cell therapy.

METHODS

We tested a series of antibodies raised against the CA125 extracellular repeat domain of MUC16 and adapted them to the CAR format. Comparisons between these candidates, and against an existing CAR targeting the MUC16 ectodomain, identified K101 as having high potency and specificity. The K101CAR was subjected to further biochemical and functional tests, including examination of the effect of soluble CA125 on its activity. Finally, we used cell lines and advanced orthotopic patient-derived xenograft (PDX) models to validate, in vivo, the efficiency of our K101CAR construct.

RESULTS

We observed a high efficacy of K101CAR T cells against cell lines and patient-derived tumors, in vitro and in vivo. We also demonstrated that K101CAR functionality was not impaired by the soluble antigen. Finally, in direct comparisons, K101CAR, which targets the CA125 extracellular repeat domains, was shown to have similar efficacy to the previously validated 4H11CAR, which targets the MUC16 ectodomain.

CONCLUSIONS

Our in vitro and in vivo results, including PDX studies, demonstrate that the CA125 domain of MUC16 represents an excellent target for treating MUC16-positive malignancies.

Selection, engineering, and in vivo testing of a human leukocyte antigen-independent T-cell receptor recognizing human mesothelin

BACKGROUND

Canonical α/β T-cell receptors (TCRs) bind to human leukocyte antigen (HLA) displaying antigenic peptides to elicit T cell-mediated cytotoxicity. TCR-engineered T-cell immunotherapies targeting cancer-specific peptide-HLA complexes (pHLA) are generating exciting clinical responses, but owing to HLA restriction they are only able to target a subset of antigen-positive patients. More recently, evidence has been published indicating that naturally occurring α/β TCRs can target cell surface proteins other than pHLA, which would address the challenges of HLA restriction. In this proof-of-concept study, we sought to identify and engineer so-called HLA-independent TCRs (HiTs) against the tumor-associated antigen mesothelin.

METHODS

Using phage display, we identified a HiT that bound well to mesothelin, which when expressed in primary T cells, caused activation and cytotoxicity. We subsequently engineered this HiT to modulate the T-cell response to varying levels of mesothelin on the cell surface.

RESULTS

The isolated HiT shows cytotoxic activity and demonstrates killing of both mesothelin-expressing cell lines and patient-derived xenograft models. Additionally, we demonstrated that HiT-transduced T cells do not require CD4 or CD8 co-receptors and, unlike a TCR fusion construct, are not inhibited by soluble mesothelin. Finally, we showed that HiT-transduced T cells are highly efficacious in vivo, completely eradicating xenografted human solid tumors.

CONCLUSION

HiTs can be isolated from fully human TCR-displaying phage libraries against cell surface-expressed antigens. HiTs are able to fully activate primary T cells both in vivo and in vitro. HiTs may enable the efficacy seen with pHLA-targeting TCRs in solid tumors to be translated to cell surface antigens.

Immunotherapy for transplantation of hepatocellular carcinoma: the next frontier in adjunctive therapy

PURPOSE OF REVIEW

The increasing success of liver transplantation in hepatocellular carcinoma (HCC) drives an ever-evolving search for innovative strategies to broaden eligible patients' pools. Recent advances in immuno-oncology have turned the spotlight on immune checkpoint inhibitors (ICIs). This review offers an updated overview of ICIs in liver transplantation for HCC, exploring neoadjuvant and adjuvant approaches and addressing unanswered questions on safety, patients' selection, and response predictors.

RECENT FINDINGS

ICIs have transitioned from being a last-chance therapeutic hope to becoming an integral cornerstone in the treatment of advanced HCC, holding great promise as a compelling option not only to downstage patients for transplantation but also as an alternative strategy in addressing posttransplantation disease recurrence. Despite ongoing refinements in immunotherapeutic agents, the complex molecular pathways involved emphasize the need for a comprehensive approach to integrate immunotherapy in liver transplantation.

SUMMARY

Initial concerns about graft rejection, with ICIs as a bridging therapy to liver transplantation, were successfully addressed using adequate immunosuppressants strategies and minimized with a sufficient washout period. Post-liver transplantation disease recurrence remains challenging, requiring a balance between effective therapy and preserving graft function. Emphasis should be placed on clinical trials validating the risk-benefit ratio of ICIs for liver transplantation, guiding appropriate patients' selection, and establishing clear management pathways.

Humanized mouse models: A valuable platform for preclinical evaluation of human cancer

Animal models are routinely employed to assess the treatments for human cancer. However, due to significant differences in genetic backgrounds, traditional animal models are unable to meet bioresearch needs. To overcome this restriction, researchers have generated and optimized immunodeficient mice, and then engrafted human genes, cells, tissues, or organs in mice so that the responses in the model mice could provide a more reliable reference for treatments. As a bridge connecting clinical application and basic research, humanized mice are increasingly used in the preclinical evaluation of cancer treatments, particularly after gene interleukin 2 receptor gamma mutant mice were generated. Human cancer models established in humanized mice support exploration of the mechanism of cancer occurrence and provide an efficient platform for drug screening. However, it is undeniable that the further application of humanized mice still faces multiple challenges. This review summarizes the construction approaches for humanized mice and their existing limitations. We also report the latest applications of humanized mice in preclinical evaluation for the treatment of cancer and point out directions for future optimization of these models.

Chimeric Antigen Receptor T Cell Therapy for Hepatocellular Carcinoma: Where Do We Stand?

Hepatocellular carcinoma (HCC) remains a global health challenge that urgently calls for innovative therapeutic strategies. Chimeric antigen receptor T cell (CAR T) therapy has emerged as a promising avenue for HCC treatment. However, the therapeutic efficacy of CAR T immunotherapy in HCC patients is significantly compromised by some major issues including the immunosuppressive environment within the tumor, antigen heterogeneity, CAR T cell exhaustion, and the advanced risk for on-target/off-tumor toxicity. To overcome these challenges, many ongoing preclinical and clinical trials are underway focusing on the identification of optimal target antigens and the decryption of the immunosuppressive milieu of HCC. Moreover, limited tumor infiltration constitutes a significant obstacle of CAR T cell therapy that should be addressed. The continuous effort to design molecular targets for CAR cells highlights the importance for a more practical approach for CAR-modified cell manufacturing. This review critically examines the current landscape of CAR T cell therapy for HCC, shedding light on the changes in innate and adaptive immune responses in the context of HCC, identifying potential CAR T cell targets, and exploring approaches to overcome inherent challenges. Ongoing advancements in scientific research and convergence of diverse treatment modalities offer the potential to greatly enhance HCC patients' care in the future.

Antigen loss following CAR-T cell therapy: Mechanisms, implications, and potential solutions

Chimeric Antigen Receptor T-cell (CAR-T cell) therapy has emerged as a groundbreaking immunotherapeutic approach for treating various hematological malignancies. CAR-T cells are engineered to express synthetic receptors that target specific antigens on cancer cells, leading to their eradication. While the therapy has shown remarkable efficacy, a significant challenge that has been observed in 30%-70% of patients showing recurrent disease is antigen loss or downregulation. We searched PubMed/MEDLINE, EMBASE, and Google scholar for articles on antigen loss/escape following Chimeric antigen receptor T-cell therapy in malignancies. Antigen loss refers to the loss or reduction in the expression of the target antigen on cancer cells, rendering CAR-T cells ineffective. This phenomenon poses a significant clinical concern, as it can lead to disease relapse and limited treatment options. This review explores the mechanisms underlying antigen loss following CAR-T cell therapy, its implications on treatment outcomes, and potential strategies to overcome the problem.

Adoptive cell therapy in paediatric extracranial solid tumours: current approaches and future challenges

Immunotherapy has ignited hope to cure paediatric solid tumours that resist traditional therapies. Among the most promising methods is adoptive cell therapy (ACT). Particularly, ACT using T cells equipped with chimeric antigen receptors (CARs) has moved into the spotlight in clinical studies. However, the efficacy of ACT is challenged by ACT-intrinsic factors, like lack of activation or T cell exhaustion, as well as immune evasion strategies of paediatric solid tumours, such as their highly immunosuppressive microenvironment. Novel strategies, including ACT using innate-like lymphocytes, innovative cell engineering techniques, and ACT combination therapies, are being developed and will be crucial to overcome these challenges. Here, we discuss the main classes of ACT for the treatment of paediatric extracranial solid tumours, reflect on the available preclinical and clinical evidence supporting promising strategies, and address the challenges that ACT is still facing. Ultimately, we highlight state-of-the-art developments and opportunities for new therapeutic options, which hold great potential for improving outcomes in this challenging patient population.

Diagnostic and Prognostic Value of Protein Post-translational Modifications in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor with high incidence and cancer mortality worldwide. Post-translational modifications (PTMs) of proteins have a great impact on protein function. Almost all proteins can undergo PTMs, including phosphorylation, acetylation, methylation, glycosylation, ubiquitination, and so on. Many studies have shown that PTMs are related to the occurrence and development of cancers. The findings provide novel therapeutic targets for cancers, such as glypican-3 and mucin-1. Other clinical implications are also found in the studies of PTMs. Diagnostic or prognostic value, and response to therapy have been identified. In HCC, it has been shown that glycosylated alpha-fetoprotein (AFP) has a higher detection rate for early liver cancer than conventional AFP. In this review, we mainly focused on the diagnostic and prognostic value of PTM, in order to provide new insights into the clinical implication of PTM in HCC.

Tyrosine kinase signaling-independent MET-targeting with CAR-T cells

BACKGROUND

Recent progress in cancer immunotherapy encourages the expansion of chimeric antigen receptor (CAR) T cell therapy in solid tumors including hepatocellular carcinoma (HCC). Overexpression of MET receptor tyrosine kinase is common in HCC; however, MET inhibitors are effective only when MET is in an active form, making patient stratification difficult. Specific MET-targeting CAR-T cells hold the promise of targeting HCC with MET overexpression regardless of signaling pathway activity.

METHODS

MET-specific CARs with CD28ζ or 4-1BBζ as co-stimulation domains were constructed. MET-CAR-T cells derived from healthy subjects (HS) and HCC patients were evaluated for their killing activity and cytokine release against HCC cells with various MET activations in vitro, and for their tumor growth inhibition in orthotopic xenograft models in vivo.

RESULTS

MET-CAR.CD28ζ and MET-CAR.4-1BBζ T cells derived from both HS and HCC patients specifically killed MET-positive HCC cells. When stimulated with MET-positive HCC cells in vitro, MET-CAR.CD28ζ T cells demonstrated a higher level of cytokine release and expression of programmed cell death protein 1 (PD-1) than MET-CAR.4-1BBζ T cells. When analyzed in vivo, MET-CAR.CD28ζ T cells more effectively inhibited HCC orthotopic tumor growth in mice when compared to MET-CAR.4-1BBζ T cells.

CONCLUSION

We generated and characterized MET-specific CAR-T cells for targeting HCC with MET overexpression regardless of MET activation. Compared with MET-CAR.4-1BBζ, MET-CAR.CD28ζ T cells showed a higher anti-HCC potency but also a higher level of T cell exhaustion. While MET-CAR.CD28ζ is preferred for further development, overcoming the exhaustion of MET-CAR-T cells is necessary to improve their therapeutic efficacy in vivo.

The Era of Immunotherapy in Hepatocellular Carcinoma: The New Mission and Challenges of Magnetic Resonance Imaging

In recent years, significant advancements in immunotherapy for hepatocellular carcinoma (HCC) have shown the potential to further improve the prognosis of patients with advanced HCC. However, in clinical practice, there is still a lack of effective biomarkers for identifying the patient who would benefit from immunotherapy and predicting the tumor response to immunotherapy. The immune microenvironment of HCC plays a crucial role in tumor development and drug responses. However, due to the complexity of immune microenvironment, currently, no single pathological or molecular biomarker can effectively predict tumor responses to immunotherapy. Magnetic resonance imaging (MRI) images provide rich biological information; existing studies suggest the feasibility of using MRI to assess the immune microenvironment of HCC and predict tumor responses to immunotherapy. Nevertheless, there are limitations, such as the suboptimal performance of conventional MRI sequences, incomplete feature extraction in previous deep learning methods, and limited interpretability. Further study needs to combine qualitative features, quantitative parameters, multi-omics characteristics related to the HCC immune microenvironment, and various deep learning techniques in multi-center research cohorts. Subsequently, efforts should also be undertaken to construct and validate a visual predictive tool of tumor response, and assess its predictive value for patient survival benefits. Additionally, future research endeavors must aim to provide an accurate, efficient, non-invasive, and highly interpretable method for predicting the effectiveness of immune therapy.

Targeted delivery of a PD-1-blocking scFv by CD133-specific CAR-T cells using nonviral Sleeping Beauty transposition shows enhanced antitumour efficacy for advanced hepatocellular carcinoma

BACKGROUND

CD133 is considered a marker for cancer stem cells (CSCs) in several types of tumours, including hepatocellular carcinoma (HCC). Chimeric antigen receptor-specific T (CAR-T) cells targeting CD133-positive CSCs have emerged as a tool for the clinical treatment of HCC, but immunogenicity, the high cost of clinical-grade recombinant viral vectors and potential insertional mutagenesis limit their clinical application.

METHODS

CD133-specific CAR-T cells secreting PD-1 blocking scFv (CD133 CAR-T and PD-1 s cells) were constructed using a sleeping beauty transposon system from minicircle technology, and the antitumour efficacy of CD133 CAR-T and PD-1 s cells was analysed in vitro and in vivo.

RESULTS

A univariate analysis showed that CD133 expression in male patients at the late stage (II and III) was significantly associated with worse progression-free survival (PFS) (P = 0.0057) and overall survival (OS) (P = 0.015), and a multivariate analysis showed a trend toward worse OS (P = 0.041). Male patients with advanced HCC exhibited an approximately 20-fold higher PD-L1 combined positive score (CPS) compared with those with HCC at an early stage. We successfully generated CD133 CAR-T and PD-1 s cells that could secrete PD-1 blocking scFv based on a sleeping beauty system involving minicircle vectors. CD133 CAR-T and PD-1 s cells exhibited significant antitumour activity against HCC in vitro and in xenograft mouse models. Thus, CD133 CAR-T and PD-1 s cells may be a therapeutically tractable strategy for targeting CD133-positive CSCs in male patients with advanced HCC.

CONCLUSIONS

Our study provides a nonviral strategy for constructing CAR-T cells that could also secrete checkpoint blockade inhibitors based on a Sleeping Beauty system from minicircle vectors and revealed a potential benefit of this strategy for male patients with advanced HCC and high CD133 expression (median immunohistochemistry score > 2.284).

Gut microbial metabolite butyrate improves anticancer therapy by regulating intracellular calcium homeostasis

BACKGROUND AND AIMS

Gut microbiota are recognized to be important for anticancer therapy, yet the underlying mechanism is not clear. Here, through the analysis of clinical samples, we identify the mechanism by which the gut microbial metabolite butyrate inhibits HCC and then explore new strategies for HCC treatment.

APPROACH AND RESULTS

In our study, we demonstrate that gut microbial metabolite butyrate improves anticancer therapy efficacy by regulating intracellular calcium homeostasis. Using liquid chromatography-mass spectrometry analysis, we found that butyrate metabolism is activated in HCC patients compared with healthy individuals. Butyrate levels are lower in the plasma of HCC patients by gas chromatography-mass spectrometry (GC-MS) analysis. Butyrate supplementation or depletion of short-chain Acyl-CoA dehydrogenase (SCAD) gene (ACADS), encoding a key enzyme for butyrate metabolism, significantly inhibits HCC proliferation and metastasis. The profiling analysis of genes upregulated by butyrate supplementation or ACADS knockdown reveals that calcium signaling pathway is activated, leading to dysregulation of intracellular calcium homeostasis and production of reactive oxygen species. Butyrate supplementation improves the therapy efficacy of a tyrosine kinase inhibitor sorafenib. On the basis of these findings, we developed butyrate and sorafenib coencapsulated mPEG-PLGA-PLL nanoparticles coated with anti-GPC3 antibody (BS@PEAL-GPC3) to prolong the retention time of drugs and enhance drug targeting, leading to high anticancer efficacy. BS@PEAL-GPC3 nanoparticles significantly reduce HCC progression. In addition, BS@PEAL-GPC3 nanoparticles display excellent HCC targeting with excellent safety.

CONCLUSIONS

In conclusion, our findings provide new insight into the mechanism by which the gut microbial metabolites inhibit HCC progression, suggesting a translatable therapeutics approach to enhance the clinical targeted therapeutic efficacy.

Bispecific antibodies redirect synthetic agonistic receptor modified T cells against melanoma

BACKGROUND

Melanoma is an immune sensitive disease, as demonstrated by the activity of immune check point blockade (ICB), but many patients will either not respond or relapse. More recently, tumor infiltrating lymphocyte (TIL) therapy has shown promising efficacy in melanoma treatment after ICB failure, indicating the potential of cellular therapies. However, TIL treatment comes with manufacturing limitations, product heterogeneity, as well as toxicity problems, due to the transfer of a large number of phenotypically diverse T cells. To overcome said limitations, we propose a controlled adoptive cell therapy approach, where T cells are armed with synthetic agonistic receptors (SAR) that are selectively activated by bispecific antibodies (BiAb) targeting SAR and melanoma-associated antigens.

METHODS

Human as well as murine SAR constructs were generated and transduced into primary T cells. The approach was validated in murine, human and patient-derived cancer models expressing the melanoma-associated target antigens tyrosinase-related protein 1 (TYRP1) and melanoma-associated chondroitin sulfate proteoglycan (MCSP) (CSPG4). SAR T cells were functionally characterized by assessing their specific stimulation and proliferation, as well as their tumor-directed cytotoxicity, in vitro and in vivo.

RESULTS

MCSP and TYRP1 expression was conserved in samples of patients with treated as well as untreated melanoma, supporting their use as melanoma-target antigens. The presence of target cells and anti-TYRP1 × anti-SAR or anti-MCSP × anti-SAR BiAb induced conditional antigen-dependent activation, proliferation of SAR T cells and targeted tumor cell lysis in all tested models. In vivo, antitumoral activity and long-term survival was mediated by the co-administration of SAR T cells and BiAb in a syngeneic tumor model and was further validated in several xenograft models, including a patient-derived xenograft model.

CONCLUSION

The SAR T cell-BiAb approach delivers specific and conditional T cell activation as well as targeted tumor cell lysis in melanoma models. Modularity is a key feature for targeting melanoma and is fundamental towards personalized immunotherapies encompassing cancer heterogeneity. Because antigen expression may vary in primary melanoma tissues, we propose that a dual approach targeting two tumor-associated antigens, either simultaneously or sequentially, could avoid issues of antigen heterogeneity and deliver therapeutic benefit to patients.

A Comprehensive Narrative Review on the History, Current Landscape, and Future Directions of Hepatocellular Carcinoma (HCC) Systemic Therapy

We provide a comprehensive review of current approved systemic treatment strategies for advanced hepatocellular carcinoma (HCC), starting with the phase III clinical trial of sorafenib which was the first to definitively show a survival benefit. After this trial, there was an initial period of little progress. However, in recent years, an explosion of new agents and combinations of agents has resulted in a markedly improved outlook for patients. We then provide the authors' current approach to therapy, i.e., "How We Treat HCC". Promising future directions and important gaps in therapy that persist are finally reviewed. HCC is a highly prevalent cancer worldwide and the incidence is growing due not only to alcoholism, hepatitis B and C, but also to steatohepatitis. HCC, like renal cell carcinoma and melanoma, is a cancer largely resistant to chemotherapy but the advent of anti-angiogenic, targeted and immune therapies have improved survival for all of these cancers. We hope this review will heighten interest in the field of HCC therapies, provide a clear outline of the current data and strategy for treatment, and sensitize readers to new developments that are likely to emerge in the near future.

An electrochemical immunosensor for the detection of Glypican-3 based on enzymatic ferrocene-tyramine deposition reaction

An ultrasensitive electrochemical immunosensor based on signal amplification of the deposition of the electroactive ferrocene-tyramine (Fc-Tyr) molecule, catalyzed by horseradish peroxidase (HRP), was constructed for the detection of the liver cancer marker Glypican-3 (GPC3). Functional electroactive molecule Fc-Tyr is reported to exhibit both the enzymatic cascade catalytic activity of tyramine signal amplification (TSA) and the excellent redox properties of ferrocene. In terms of design, the low matrix effects inherent in using the magnetic bead platforms, a quasi-homogeneous system, allowed capturing the target protein GPC3 without sample pretreatment, and loading HRP to trigger the TSA, which induced a large amount of Fc-Tyr deposited on the electrode surface layer by layer as a signal probe for the detection of GPC3. The concept of Fc-Tyr as an electroactive label was validated, GPC3 biosensor exhibited high selectivity and sensitivity to GPC3 in the range of 0.1 ng mL^-1-1 μg mL^-1. Finally, the sensor was used simultaneously with ELISA to assess GPC3 levels in the serum of clinical liver cancer patients, and the results showed consistency, with a recovery of 98.33-105.35% and a relative standard deviation (RSD) of 4.38-8.18%, providing a theoretical basis for achieving portable, rapid and point of care testing (POCT) of tumor markers.