When immunotherapy meets liver transplantation for hepatocellular carcinoma: A bumpy but promising road

Liver transplantation(LT)is a highly curative therapy for patients with hepatocellular carcinoma(HCC).However,due to the shortage of donor livers and rapid progression of HCC,a majority of patients are dropped out from the waitlist.Recently,immunotherapy has shown great promise in the treatment of advanced HCC.However,the use of immunotherapy is limited in LT mainly due to the potentially increasing risk of graft rejection.One of the main challenges for researchers is the protection of donor graft from an immunotherapy-boosted immune response mounted by the host.Besides,the safety,availability,and costs of immunotherapy are other challenges that need to be addressed.Here,we reviewed the literature involving patients who received immunotherapy prior to transplant to avoid waitlist dropouts and following transplantation to prevent the progression of tumor recurrence and metastasis.Statistically,the incidence of rejection was 25.0%pre-transplant and 18.5%post-transplant.Based on the review of these clinical studies,we can conclude that conducting clinical trials on the safety and efficacy of currently available immunotherapy drugs and identifying novel immunotherapy targets through extensive research may be promising for patients who do not meet the selection criteria for LT and who experience post-transplant recurrence.To date,the clinical experience on the use of immunotherapy before or after LT comes from individual case studies.Although some of the reported results are promising,they are not sufficient to support the standardized use of immunotherapy in clinical practice.

Tumor neoantigens: Novel strategies for application of cancer immunotherapy

Neoantigen-targeted immunotherapy is a rapidly advancing field that holds great promise for treating cancer.The recognition of antigens by immune cells is a crucial step in tumor-specific killing,and neoantigens generated by mutations in cancer cells possess high immunogenicity and are selectively expressed in tumor cells,making them an attractive therapeutic target.Currently,neoantigens find utility in various domains,primarily in the realm of neoantigen vaccines such as DC vaccines,nucleic acid vaccines,and synthetic long peptide vaccines.Additionally,they hold promise in adoptive cell therapy,encompassing tumor-infiltrating cells,T cell receptors,and chimeric antigen receptors which are expressed by genetically modified T cells.In this review,we summarized recent progress in the clinical use of tumor vaccines and adoptive cell therapy targeting neoantigens,discussed the potential of neoantigen burden as an immune checkpoint in clinical settings.With the aid of state-of-the-art sequencing and bioinformatics technologies,together with significant advancements in artificial intelligence,we anticipated that neoantigens will be fully exploited for personalized tumor immunotherapy,from screening to clinical application.

Immunotherapy in gastric cancer

Gastric cancer is the second most common of cancerrelated deaths worldwide.In the majority of cases gastric cancer is advanced at diagnosis and although medical and surgical treatments have improved,survival rates remain poor.Cancer immunotherapy has emerged as a powerful and promising clinical approach for treatment of cancer and has shown major success in breast cancer,prostate cancer and melanoma.Here,we provide an overview of concepts of modern cancer immunotherapy including the theory,current approaches,remaining hurdles to be overcome,and the future prospect of cancer immunotherapy in the treatment of gastric cancer.Adaptive cell therapies,cancer vaccines,gene therapies,monoclonal antibody therapies have all been used with some initial successes in gastric cancer.However,to date the results in gastric cancer have been disappointing as current approaches often do not stimulate immunity efficiently allowing tumors continue to grow despite the presence of a measurable immune response.Here,we discuss the identification of targets for immunotherapy and the role of biomarkers in prospectively identifying appropriate subjects or immunotherapy.We also discuss the molecular mechanisms by which tumor cells escape host immunosurveillance and produce an immunosuppressive tumor microenvironment.We show how advances have provided tools for overcoming the mechanisms of immunosuppression including the use of monoclonal antibodies to block negative regulators normally expressed on the surface of T cells which limit activation and proliferation of cytotoxic T cells.Immunotherapy has greatly improved and is becoming an important factor in such fields as medical care and welfare for human being.Progress has been rapid ensuring that the future of immunotherapy for gastric cancer is bright.

Recent advances in immunotherapy for hepatocellular carcinoma

Background:Treatment of hepatocellular carcinoma(HCC)is challenging as most patients are diagnosed at advanced stage with underlying chronic liver conditions.Conventional systemic chemotherapy has failed in HCC,and the clinical efficacy of FDA-approved molecular targeted agents such as sorafenib and lenvatinib remains unsatisfactory.Data sources:Literature search was conducted in Pub Med for relevant articles published before January 2021.The search aimed to identify recent developments in immune-based treatment approaches for HCC.Information of clinical trials was obtained from https://clinicaltrials.gov/.Results:Two immune checkpoint inhibitors(ICIs),nivolumab and pembrolizumab were approved as monotherapies,which has revolutionized HCC treatment.Besides,combination ICIs have also got accelerated FDA approval recently.Immune-based therapies have challenged targeted drugs owing to their safety,tolerability,and survival benefits.In addition to the significant success in ICIs,other immunotherapeutic strategies such as cancer vaccine,chimeric antigen receptor T-cells,natural killer cells,cytokines,and combination therapy,have also shown promising outcomes in clinical trials.Various diagnostic and prognostic biomarkers have been identified which can help in clinical decision making when starting treatment with ICIs.Conclusions:Immunotherapy has emerged as one of the mainstream treatment modalities for advanced HCC in recent years.However,challenges such as low response rate and acquired resistance in previously respondent patients still exist.Further research is needed to understand the unique resistance mechanism to immunotherapy and to discover more predictive biomarkers to guide clinical decision making.

Personalized immunotherapy in cancer precision medicine

With the significant advances in cancer genomics using next-generation sequencing technologies,genomic and molecular profilingbased precision medicine is used as a part of routine clinical test for guiding and selecting the most appropriate treatments for individual cancer patients.Although many molecular-targeted therapies for a number of actionable genomic alterations have been developed,the clinical application of such information is still limited to a small proportion of cancer patients.In this review,we summarize the current status of personalized drug selection based on genomic and molecular profiling and highlight the challenges how we can further utilize the individual genomic information.Cancer immunotherapies,including immune checkpoint inhibitors,would be one of the potential approaches to apply the results of genomic sequencing most effectively.Highly cancer-specific antigens derived from somatic mutations,the so-called neoantigens,occurring in individual cancers have been in focus recently.Cancer immunotherapies,which target neoantigens,could lead to a precise treatment for cancer patients,despite the challenge in accurately predicting neoantigens that can induce cytotoxic T cells in individual patients.Precise prediction of neoantigens should accelerate the development of personalized immunotherapy including cancer vaccines and T-cell receptor-engineered T-cell therapy for a broader range of cancer patients.

Immunotherapy in human colorectal cancer: challenges and prospective

Human colorectal cancer(CRC) is the third most commonly diagnosed malignancies and the prognosis for patients with recurrent or metastatic disease is extremely poor. Although new chemotherapeutic regimen improves survival rates, therapy with better efficacy and less adverse effects is drastically needed. Immunotherapy has been investigated in human CRC for decades with limited success. However, recent developments of immunotherapy, particularly immune checkpoint inhibitor therapy, have achieved promising clinical benefits in many types of cancer and revived the hope for utilizing such therapy in human CRC. In this review, we will discuss important immunological landscape within the CRC microenvironment and introduce immunoscore system to better describe immunophenotyping in CRC. We will also discuss different immunotherapeutic approaches currently utilized in different phases of clinical trials. Some of those completed or ongoing trials are summarized. Finally, we provide a brief prospective on the future human CRC immunotherapy.

Hepatocellular carcinoma and immunotherapy:Beyond immune checkpoint inhibitors

Hepatocellular carcinoma(HCC)is one of the deadliest and most common malignancies of the liver.Considering the rich immune background of carcinogenesis in HCC,efforts have been focused on further understanding the role of the immune system in tumor suppression and promotion.The utilization of immunotherapy in HCC has led to encouraging results that has translated to longer survival and better quality of life among patients.The development of novel HCC-tailored regimens such as vaccine therapy and adoptive cellular therapy coupled with a deeper understanding of biomarkers predictive of the response to immunotherapy will lead to better treatment outcomes.

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.

Penile cancer:Updates in systemic therapy

Penile cancer is a rare genitourinary malignancy with a greater incidence in parts of Asia,South America,and Africa.Outcomes are very poor in patients with advanced disease and in those who do not respond to frstine mutimodal therapy.Among systemic therapy options,platinum-based chemotherapy is used in the frst line;however,approximately half of patients do not benefit.Response rates to systeric therapy as subsequent line treatment are historically dismal.There is also a paucity of prognostic and predictive tools within the context of penile cancer.As such,there remains an urgent need to expand systemic treatment options for patients with advanced penile cancer.The purpose of this review is to summarize the existing evidence for standard-of-care lines of systemic treatment,examine the potential of novel lines of systemic therapy,and provide an update as to the status of these new therapies within the context of penile cancer.

Double-negative T cells:a promising avenue of adoptive cell therapy in transplant oncology

Tumor recurrence is one of the major life-threatening complications after liver transplantation for liver cancer.In addition to the common mechanisms underlying tumor recurrence,another unavoidable problem is that the immunosuppressive therapeutic regimen after transplantation could promote tumor recurrence and metastasis.Transplant oncology is an emerging field that addresses oncological challenges in transplantation.In this context,a comprehensive therapeutic management approach is required to balance the anti-tumor treatment and immunosuppressive status of recipients.Double-negative T cells(DNTs)are a cluster of heterogeneous cells mainly consisting of two subsets stratified by T cell receptor(TCR)type.Among them,TCRαβ^(+)DNTs are considered to induce immune suppression in immune-mediated diseases,while TCRγδ^(+)DNTs are widely recognized as tumor killers.As a composite cell therapy,healthy donor-derived DNTs can be propagated to therapeutic numbers in vitro and applied for the treatment of several malignancies without impairing normal tissues or being rejected by the host.In this work,we summarized the biological characteristics and functions of DNTs in oncology,immunology,and transplantation.Based on the multiple roles of DNTs,we propose that a new balance could be achieved in liver transplant oncology using them as an off-the-shelf adoptive cell therapy(ACT).

Ginsenoside Rg1 improves anti-tumor efficacy of adoptive cell therapy by enhancing T cell effector functions

Adoptive cell therapy(ACT)has emerged with remarkable efficacies for tumor immunotherapy.Chimeric antigen receptor(CAR)T cell therapy,as one of most promising ACTs,has achieved prominent effects in treating malignant hematological tumors.However,the insufficient killing activity and limited persistence of T cells in the immunosuppressive tumor microenvironment limit the further application of ACTs for cancer patients.Many studies have focused on improving cytotoxicity and persistence of T cells to achieve improved therapeutic effects.In this study,we explored the potential function in ACT of ginsenoside Rg1,the main pharmacologically active component of ginseng.We introduced Rg1 during the in vitro activation and expansion phase of T cells,and found that Rg1 treatment upregulated two T cell activation markers,CD69 and CD25,while promoting T cell differentiation towards a mature state.Transcriptome sequencing revealed that Rg1 influenced T cell metabolic reprogramming by strengthening mitochondrial biosynthesis.When co-cultured with tumor cells,Rg1-treated T cells showed stronger cytotoxicity than untreated cells.Moreover,adding Rg1 to the culture endowed CAR-T cells with enhanced anti-tumor efficacy.This study suggests that ginsenoside Rg1 provides a potential approach for improving the anti-tumor efficacy of ACT by enhancing T cell effector functions.

Synthetic biology approaches for improving the specificity and efficacy of cancer immunotherapy

Immunotherapy has shown robust efficacy in treating a broad spectrum of hematological and solid cancers.Despite the transformative impact of immunotherapy on cancer treatment,several outstanding challenges remain.These challenges include on-target off-tumor toxicity,systemic toxicity,and the complexity of achieving potent and sustainable therapeutic efficacy.Synthetic biology has emerged as a promising approach to overcome these obstacles,offering innovative tools for engineering living cells with customized functions.This review provides an overview of the current landscape and future prospects of cancer immunotherapy,particularly emphasizing the role of synthetic biology in augmenting its specificity,controllability,and efficacy.We delineate and discuss two principal synthetic biology strategies:those targeting tumor surface antigens with engineered immune cells and those detecting intratumoral disease signatures with engineered gene circuits.This review concludes with a forwardlooking perspective on the enduring challenges in cancer immunotherapy and the potential breakthroughs that synthetic biology may contribute to the field.

Immunotherapy for hepatocellular carcinoma

Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths worldwide.Its high recurrence rate and lack of effective control drugs result in a 5-year survival rate of only about 10%.HCC is a tumor regulated by the immune system.Significant breakthroughs have occurred in treating solid tumors with immunotherapy in recent years.Various immunotherapies,such as immune checkpoint inhibitors(ICIs),including combination therapies,have demonstrated promising therapeutic effects in both clinical applications and research.Other immunotherapies,such as adoptive cell therapies and oncolytic viruses,are also emerging,offering hope for addressing long-term survival issues in HCC.This article reviews current commonly used immunotherapy strategies and the latest research findings for reference.

Recent advances and remaining challenges in lung cancer therapy

Lung cancer remains the most common cause of cancer death.Given the continued research into new drugs and combination therapies,outcomes in lung cancer have been improved,and clinical benefits have been expanded to a broader patient population.However,the overall cure and survival rates for lung cancer patients remain low,especially in metastatic cases.Among the available lung cancer treatment options,such as surgery,radiation therapy,chemotherapy,targeted therapies,and alternative therapies,immunotherapy has shown to be the most promising.The exponential progress in immuno-oncology research and recent advancements made in the field of immunotherapy will further increase the survival and quality of life for lung cancer patients.Substantial progress has been made in targeted therapies using tyrosine kinase inhibitors and monoclonal antibody immune checkpoint inhibitors with many US Food And Drug Administration(FDA)-approved drugs targeting the programmed cell death ligand-1 protein(e.g.,durvalumab,atezolizumab),the programmed cell death-1 receptor(e.g.,nivolumab,pembrolizumab),and cytotoxic T-lymphocyte-associated antigen 4(e.g.,tremelimumab,ipilimumab).Cytokines,cancer vaccines,adoptive T cell therapies,and Natural killer cell mono-and combinational therapies are rapidly being studied,yet to date,there are currently none that are FDA-approved for the treatment of lung cancer.In this review,we discuss the current lung cancer therapies with an emphasis on immunotherapy,including the challenges for future research and clinical applications.

Evaluation of the safety and efficiency of cytotoxic T cell therapy sensitized by tumor antigens original from T-ALL-iPSC in vivo

Background:Since RNA sequencing has shown that induced pluripotent stem cells(iPSCs)share a common antigen profile with tumor cells,cancer vaccines that focus on iPSCs have made promising progress in recent years.Previously,we showed that iPSCs derived from leukemic cells of patients with primary T cell acute lymphoblastic leukemia(T-ALL)have a gene expression profile similar to that of T-ALL cell lines.Methods:Mice with T-ALL were treated with dendritic and T(DC-T)cells loaded with intact and complete antigens from T-ALL-derived iPSCs(T-ALL-iPSCs).We evaluated the safety and antitumor efficiency of autologous tumor-derived iPSC antigens by flow cytometry,cytokine release assay,acute toxicity experiments,long-term toxicity experiments,and other methods.Results:Our results indicate that complete tumor antigens from T-ALL-iPSCs could inhibit the growth of inoculated tumors in immunocompromised mice without causing acute and long-term toxicity.Conclusion:T-ALL-iPSC-based treatment is safe and can be used as a potential strategy for leukemia immunotherapy.

Anti-cd TCR antibody-expanded cd T cells:a better choice for the adoptive immunotherapy of lymphoid malignancies

Cell-based immunotherapy for lymphoid malignancies has gained increasing attention as patients develop resistance to conventional treatments.cd T cells,which have major histocompatibility complex(MHC)-unrestricted lytic activity,have become a promising candidate population for adoptive cell transfer therapy.We previously established a stable condition for expanding cd T cells by using anti-cd T-cell receptor(TCR)antibody.In this study,we found that adoptive transfer of the expanded cd T cells to Daudi lymphoma-bearing nude mice significantly prolonged the survival time of the mice and improved their living status.We further investigated the characteristics of these antibody-expanded cd T cells compared to the more commonly used phosphoantigen-expanded cd T cells and evaluated the feasibility of employing them in the treatment of lymphoid malignancies.Slow but sustained proliferation of human peripheral blood cd T cells was observed upon stimulation with anti-cd TCR antibody.Compared to phosphoantigen-stimulated cd T cells,the antibody-expanded cells manifested similar functional phenotypes and cytotoxic activity towards lymphoma cell lines.It is noteworthy that the anti-cd TCR antibody could expand both the Vd1 and Vd2 subsets of cd T cells.The in vitro-expanded Vd1 T cells displayed comparable tumour cell-killing activity to Vd2 T cells.Importantly,owing to higher C–C chemokine receptor 4(CCR4)and CCR8 expression,the Vd1 T cells were more prone to infiltrate CCL17-or CCL22-expressing lymphomas than the Vd2 T cells.Characterizing the peripheral blood cd T cells from lymphoma patients further confirmed that the anti-cd TCR antibody-expanded cd T cells could be a more efficacious choice for the treatment of lymphoid malignancies than phosphoantigen-expanded cd T cells.

T cells expressing a LMP1-specific chimeric antigen receptor mediate antitumor effects against LMP1-positive nasopharyngeal carcinoma cells in vitro and in vivo

T cells modified with chimeric antigen receptor are an attractive strategy to treat Epstein-Barr virus（EBV） associated malignancies.The EBV latent membrane protein 1（LMP1） is a 66-KD integral membrane protein encoded by EBV that consists of transmembrane-spanning loops.Previously,we have identified a functional signal chain variable fragment（scFv） that specifically recognizes LMP1 through phage library screening.Here,we constructed a LMP1 specific chimeric antigen receptor containing anti-LMP1 scFv,the CD28 signalling domain,and the CD3ζchain（HELA/CAR）.We tested its functional ability to target LMP1 positive nasopharyngeal carcinoma cells.HELA/CAR cells were efficiently generated using lentivirus vector encoding the LMP1-specific chimeric antigen receptor to infect activated human CD3＋ T cells.The HELA/CAR T cells displayed LMP1 specific cytolytic action and produced IFN-γ and IL-2 in response to nasopharyngeal carcinoma cells overexpressing LMP1.To demonstrate in vivo anti-tumor activity,we tested the HELA/CAR T cells in a xenograft model using an LMP1 overexpressing tumor.Intratumoral injection of anti-LMP1 HELA/CAR-T cells significantly reduced tumor growth in vivo.These results show that targeting LMP1 using HELA/CAR cells could represent an alternative therapeutic approach for patients with EBV-positive cancers.

Cellular based treatment modalities for unresectable hepatocellular carcinoma

Hepatocellular carcinoma(HCC)is the most common primary malignancy of the liver and is unfortunately associated with an overall poor prognosis and high mortality.Early and intermediate stages of HCC allow for treatment with surgical resection,ablation and even liver transplantation,however disease progression warrants conventional systemic therapy.For years treatment options were limited to molecular-targeting medications,of which sorafenib remains the standard of care.The recent development and success of immune checkpoint inhibitors has proven to be a breakthrough in the treatment of HCC,but there is an urgent need for the development of further novel therapeutic treatments that prolong overall survival and minimize recurrence.Current investigation is focused on adoptive cell therapy including chimeric antigen receptor-T cells(CAR-T cells),T cell receptor(TCR)engineered T cells,dendritic cells,natural killer cells,and tumor infiltrating lymphocyte cells,which have shown remarkable success in the treatment of hematological and solid tumor malignancies.In this review we briefly introduce readers to the currently approved systemic treatment options and present clinical and experimental evidence of HCC immunotherapeutic treatments that will hopefully one day allow for revolutionary change in the treatment modalities used for unresectable HCC.We also provide an up-to-date compilation of ongoing clinical trials investigating CAR-T cells,TCR engineered T cells,cancer vaccines and oncolytic viruses,while discussing strategies that can help overcome commonly faced challenges when utilizing cellular based treatments.

Natural killer cell-derived extracellular vesicle significantly enhanced adoptive T cell therapy against solid tumors via versatilely immunomodulatory coordination

Insufficient tumor tropism,MHC classⅠmolecules(MHC-I)defects of tumor cells,and immunosuppressive tumor microenvironment(TME)seriously imperil the efficacy of adoptive T cell therapy on solid tumors.Here,natural killer cell-derived extracellular vesicle(Nev)is used as a versatile toolkit to synergistically improve adoptive T cell therapy for solid tumors.Specifically,Nev is modified with dibenzocyclooctynes(DBCO)linked with p H-sensitive benzoic-imine bonds;meanwhile,cytotoxic T lymphocyte(CTL)is decorated with azide groups.Then CTL is armed with Nev(CTL-Nev)through the click chemistry reaction.After systematic administration,Nev obviously promotes the tumor-targeting accumulation of CTL coming from its native tumor-tropism capability.Then,the cleavage of benzoic-imine bonds in the slightly acidic TME leads to the release of Nev,which not only directly induces tumor apoptosis but also promotes the action of CTL via multiplex pathways,such as up-regulating the MHC-I expression on tumor cells,reprogramming tumor-associated macrophages from pro-tumoral M2 phenotypes to tumoricidal M1 phenotypes.The all-around coordination of Nev with CTL results in potent tumor repression.