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

Background: Chimeric antigen receptor-engineered T-cell(CAR-T) therapy is a newly developed immunotherapy used in the treatment of cancers. Because CAR-T therapy has shown great success in treating CD19-positive hematological malignancies, its application has been explored in the treatment of solid tumors, such as liver cancer. In this review, we discuss the immune characteristics of liver cancer, the obstacles encountered during the application of CAR-T therapy, and preclinical and clinical progress in the use of CAR-T therapy in patients with liver cancer.Data sources: The data on CAR-T therapy related to liver cancers were collected by searching Pub Med and the Web of Science databases prior to December 2017 with the keywords "chimeric antigen receptor","CAR-T", "liver cancer", "hepatocellular carcinoma", and "solid tumor". Additional articles were identified by manual search of references found in the primary articles. The data for clinical trials were collected by searching Clinical Trials.gov.Results: The liver has a tolerogenic nature in the intrahepatic milieu and its tumor microenvironment significantly affects tumor progression. The obstacles that reduce the efficacy of CAR-T therapy in solid tumors include a lack of specific tumor antigens, limited trafficking and penetration of CAR-T cells to tumor sites, and an immunosuppressive tumor microenvironment. To overcome these obstacles, several strategies have emerged. In addition, several strategies have been developed to manage the side effects of CAR-T, including enhancing the selectivity of CARs and controlling CAR-T activity. To date, no clinical trials of CAR-T therapy against HCC have been completed. However, preclinical studies in vitro and in vivo have shown potent antitumor efficacy. Glypican-3, mucin-1, epithelial cell adhesion molecule, carcinoembryonic antigen, and other targets are currently being studied.Conclusions: The application of CAR-T therapy for liver cancer is just beginning to be explored and more research is needed. However, we are optimistic that CAR-T therapy will offer a new approach for the treatment of liver cancers in the future.

The human application of gene therapy to re-program T-cell specificity using chimeric antigen receptors

The adoptive transfer of T cells is a promising approach to treat cancers. Primary human T cells can be modified using viral and non-viral vectors to promote the specific targeting of cancer cells via the introduction of exogenous T-cell receptors(TCRs) or chimeric antigen receptors(CARs). This gene transfer displays the potential to increase the specificity and potency of the anticancer response while decreasing the systemic adverse effects that arise from conventional treatments that target both cancerous and healthy cells. This review highlights the generation of clinical-grade T cells expressing CARs for immunotherapy, the use of these cells to target B-cell malignancies and, particularly, the first clinical trials deploying the Sleeping Beauty gene transfer system, which engineers T cells to target CD19+ leukemia and non-Hodgkin's lymphoma.

Chidamide and sintilimab combination in diffuse large B-cell lymphoma progressing after chimeric antigen receptor T therapy

BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is curable with first-line chemoimmunotherapy but patients with relapsed/refractory(R/R)DLBCL still face a poor prognosis.For patients with R/R DLBCL,the complete response rate to traditional next-line therapy is only 7%and the median overall survival is 6.3 mo.Recently,CD19-targeting chimeric antigen receptor T cells(CAR-T)have shown promise in clinical trials.However,approximately 50%of patients treated with CAR-T cells ultimately progress and few salvage therapies are effective.CASE SUMMARY Here,we report on 7 patients with R/R DLBCL whose disease progressed after CAR-T infusion.They received a PD-1 inhibitor(sintilimab)and a histone deacetylase inhibitor(chidamide).Five of the 7 patients tolerated the treatment without any serious adverse events.Two patients discontinued the treatment due to lung infection and rash.At the 20-mo follow-up,the median overall survival of these 7 patients was 6 mo.Of note,there were 2 complete response rates(CRs)and 2 partial response rates(PRs)during this novel therapy,with an overall response rate(ORR)of 57.1%,and one patient had a durable CR that lasted at least 20 mo.CONCLUSION In conclusion,chidamide combined with sintilimab may be a choice for DLBCL patients progressing after CD19-targeting CAR-T therapy.

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.

Chimeric antigen receptors:On the road to realising their full potential

Chimeric antigen receptors(CARs) are fusion molecules that may be genetically delivered ex-vivo to T-cells and other immune cell populations,thereby conferring specificity for native target antigens found on the surface of tumour and other target cell types. Antigen recognition by CARs is neither restricted by nor dependent upon human leukocyte antigen antigen expression,favouring widespread use of this technology across transplantation barriers. Signalling is delivered by a designer endodomain that provides a tailored and target-dependent activation signal to polyclonal circulating T-cells. Recent clinical data emphasise the enormous promise of this emerging immunotherapeutic strategy for B-cell malignancy,notably acute lymphoblastic leukaemia. In that context,CARs are generally targeted against the ubiquitous B-cell antigen,CD19. However,CAR T-cell immunotherapy is limited by potential for severe on-target toxicity,notably due to cytokine release syndrome. Furthermore,efficacy in the context of solid tumours remains unproven,owing in part to lack of availability of safe tumour-specific targets,inadequate CAR T-cell homing and hostility of the tumour microenvironment to immune effector deployment. Manufacture and commercial development of this strategy also impose new challenges not encountered with more traditional drug products. Finally,there is increasing interest in the application of this technology to the treatment of non-malignant disease states,such as autoimmunity,chronic infection and in the suppression of allograft rejection. Here,we consider the background and direction of travel of this emerging and highly promising treatment for malignant and other disease types.

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.

Revolutionizing gastric cancer treatment:The potential of immunotherapy

Gastric cancer,a prevalent malignancy worldwide,ranks sixth in terms of frequency and third in fatality,causing over a million new cases and 769000 annual deaths.Predominant in Eastern Europe and Eastern Asia,risk factors include family medical history,dietary habits,tobacco use,Helicobacter pylori,and Epstein-Barr virus infections.Unfortunately,gastric cancer is often diagnosed at an advanced stage,leading to a grim prognosis,with a 5-year overall survival rate below 5%.Surgical intervention,particularly with D2 Lymphadenectomy,is the mainstay for early-stage cases but offers limited success.For advanced cases,the National Comprehensive Cancer Network recommends chemotherapy,radiation,and targeted therapy.Emerging immunotherapy presents promise,especially for unresectable or metastatic cases,with strategies like immune checkpoint inhibitors,tumor vaccines,adoptive immunotherapy,and nonspecific immunomodulators.In this Editorial,with regards to the article“Advances and key focus areas in gastric cancer immunotherapy:A comprehensive scientometric and clinical trial review”,we address the advances in the field of immunotherapy in gastric cancer and its future prospects.

Targeting the HIV reservoir:chimeric antigen receptor therapy for HIV cure

Although antiretroviral therapy(ART)can reduce the viral load in the plasma to undetectable levels in human immunodeficiency virus(HIV)-infected individuals,ART alone cannot completely eliminate HIV due to its integration into the host cell genome to form viral reservoirs.To achieve a functional cure for HIV infection,numerous preclinical and clinical studies are underway to develop innovative immunotherapies to eliminate HIV reservoirs in the absence of ART.Early studies have tested adoptive T-cell therapies in HIV-infected individuals,but their effectiveness was limited.In recent years,with the technological progress and great success of chimeric antigen receptor(CAR)therapy in the treatment of hematological malignancies,CAR therapy has gradually shown its advantages in the field of HIV infection.Many studies have identified a variety of HIV-specific CAR structures and types of cytolytic effector cells.Therefore,CAR therapy may be beneficial for enhancing HIV immunity,achieving HIV control,and eliminating HIV reservoirs,gradually becoming a promising strategy for achieving a functional HIV cure.In this review,we provide an overview of the design of anti-HIV CAR proteins,the cell types of anti-HIV CAR(including CAR T cells,CAR natural killer cells,and CAR-encoding hematopoietic stem/progenitor cells),the clinical application of CAR therapy in HIV infection,and the prospects and challenges in anti-HIV CAR therapy for maintaining viral suppression and eliminating HIV reservoirs.

Advances in the development of chimeric antigen receptor-T-cell therapy in B-cell acute lymphoblastic leukemia

CD19-targeted chimeric antigen receptor T-cell(CAR-T)therapy is effective in refractory/relapsed(R/R)B-cell acute lymphoblastic leukemia(B-ALL).This review focuses on achievements,current obstacles,and future directions in CAR-T research.A high complete remission rate of 68%to 93%could be achieved after anti-CD19 CAR-T treatment for B-ALL.Cytokine release syndrome and CAR-T-related neurotoxicity could be managed.In view of difficulties collecting autologous lymphocytes,universal CAR-T is a direction to explore.Regarding the high relapse rate after anti-CD19 CAR-T therapy,the main solutions have been developing new targets including CD22 CAR-T,or CD19/CD22 dual CAR-T.Additionally,some studies showed that bridging into transplant post-CAR-T could improve leukemia-free survival.Some patients who did not respond to CAR-T therapy were found to have an abnormal conformation of the CD19 exon or trogocytosis.Anti-CD19 CAR-T therapy for R/R B-ALL is effective.From individual to universal CAR-T,from one target to multi-targets,CAR-T-cell has a chance to be off the shelf in the future.

Megakaryocyte aplastic thrombocytopeniaafter CAR T-cell therapy in a patient withmultiple myeloma:A case report

Chimeric antigen receptor(CAR)T-cell therapy is an effective new treatment strategy for hematologic malignancies.The success of CAR T-cell therapy in treating leukemia and lymphoma has promoted its development for multiple myeloma(MM),and the initial results of CAR T cell therapy have been encouraging.CAR T-cell therapy target antigens that have been clinically evaluated in MM;these antigens include CD19,B cell maturation antigen(BCMA),CD38,and CD138.A barrier to the widespread use of CAR T-cell therapy is its toxicity,primarily cytokine release syndrome(CRS),and neurologic toxicity.This study reports a patient with refractory MM who also developed megakaryocyte aplastic thrombocytopenia after receiving CAR T-cell therapy;such a case or the unusual side effects involving medications are yet unreported.There are risks in using cyclosporine and other immunosuppressants that may lead to MM recurrence as the use of such substances is contradictory to previous treatments;therefore,we temporarily administered platelet infusion as supportive care.Thus far,the condition of the patient has been steady and the patient regularly takes blood test in the hospital.

Generating universal chimeric antigen receptor expressing cell products from induced pluripotent stem cells:beyond the autologous CAR-T cells

Adoptive therapeutic immune cells, such as chimeric antigen receptor (CAR)-T cells and natural killer cells, have established a new generation of precision medicine based on which dramatic breakthroughs have been achieved in intractable lymphoma treatments. Currently, well-explored approaches focus on autologous cells due to their low immunogenicity, but they are highly restricted by the high costs, time consumption of processing, and the insufficiency of primary cells in some patients. Induced pluripotent stem cells (iPSCs) are cell sources that can theoretically produce indefinite well-differentiated immune cells. Based on the above facts, it may be reasonable to combine the iPSC technology and the CAR design to produce a series of highly controllable and economical "live" drugs. Manufacturing hypoimmunogenic iPSCs by inactivation or over-expression at the genetic level and then arming the derived cells with CAR have emerged as a form of "off-the-shelf" strategy to eliminate tumor cells efficiently and safely in a broader range of patients. This review describes the reasonability, feasibility, superiority, and drawbacks of such approaches, summarizes the current practices and relevant research progress, and provides insights into the possible new paths for personalized cell-based therapies.

ncreasing the safety and efficacy of chimeric antigen receptor T cell therapy

Chimeric antigen receptor （CAR） T cell therapy is a promising cancer treatment that has recently been undergoing rapid development. However, there are still some major challenges, including precise tumor targeting to avoid off-target or ＂on-target/off-tumor＂ toxicity, adequate T cell infiltration and migration to solid tumors and T cell proliferation and persistence across the physical and biochemical barriers of solid tumors. In this review, we focus on the primary challenges and strafegies to design safe and effective CAR T cells, including using novel cutting-edge technologies for CAR and vecfor designs to increase both the safety and efficacy, further T cell modification to overcome the tumorassociated immune suppression, and using gene editing technologies to generate universal CAR T cells. All these efforts promote the development and evolution of CAR T cell therapy and move toward our ultimate goal--curing cancer with high safety, high efficacy, and low cost.

Advancing chimeric antigen receptor T cel therapy with CRISPR/Cas9

The clustered regularly interspaced short palindromic repeats （CRISPR）/CRISPR-associated 9 （CRISPR/Casg） system, an RNA-guided DNA targeting technology, is triggering a revolution in the field of biology. CRISPR/ Cas9 has demonstrated great potential for genetic manipulation. In this review, we discuss the current development of CRISPR/Cas9 technologies for thera- peutic applications, especially chimeric antigen receptor （CAR） T cell-based adoptive immunotherapy. Different methods used to facilitate efficient CRISPR delivery and gene editing in T cells are compared. The potential of genetic manipulation using CRISPR/Cas9 system to generate universal CAR T cells and potent T cells that are resistant to exhaustion and inhibition is explored. We also address the safety concerns associated with the use of CRISPR/Cas9 gene editing and provide potential solutions and future directions of CRISPR application in the field of CAR T cell immunotherapy. As an integration-free gene insertion method, CRISPR/Cas9 holds great promise as an efficient gene knock-in platform. Given the tremendous progress that has been made in the past few years, we believe that the CRISPPJ Cas9 technology holds immense promise for advancing immunotherapy.

Chimeric antigen receptor- and natural killer cell receptor-engineered innate killer cells in cancer immunotherapy

Chimeric antigen receptor(CAR)-engineered T-cell(CAR-T)therapy has demonstrated impressive therapeutic efficacy against hematological malignancies,but multiple challenges have hindered its application,particularly for the eradication of solid tumors.Innate killer cells(IKCs),particularly NK cells,NKT cells,andγδT cells,employ specific antigen-independent innate tumor recognition and cytotoxic mechanisms that simultaneously display high antitumor efficacy and prevent tumor escape caused by antigen loss or modulation.IKCs are associated with a low risk of developing GVHD,thus offering new opportunities for allogeneic“off-the-shelf”cellular therapeutic products.The unique innate features,wide tumor recognition range,and potent antitumor functions of IKCs make them potentially excellent candidates for cancer immunotherapy,particularly serving as platforms for CAR development.In this review,we first provide a brief summary of the challenges hampering CAR-T-cell therapy applications and then discuss the latest CAR-NK-cell research,covering the advantages,applications,and clinical translation of CAR-and NK-cell receptor(NKR)-engineered IKCs.Advances in synthetic biology and the development of novel genetic engineering techniques,such as gene-editing and cellular reprogramming,will enable the further optimization of IKC-based anticancer therapies.

Cancer stem cell-targeted chimeric antigen receptor(CAR)-T cell therapy: Challenges and prospects

Cancer stem cells(CSCs)with their self-renewal ability are accepted as cells which initiate tumors.CSCs are regarded as interesting targets for novel anticancer therapeutic agents because of their association with tumor recurrence and resistance to conventional therapies,including radiotherapy and chemotherapy.Chimeric antigen receptor(CAR)-T cells are engineered T cells which express an artificial receptor specific for tumor associated antigens(TAAs)by which they accurately target and kill cancer cells.In recent years,CAR-T cell therapy has shown more efficiency in cancer treatment,particularly regarding blood cancers.The expression of specific markers such as TAAs on CSCs in varied cancer types makes them as potent tools for CAR-T cell therapy.Here we review the CSC markers that have been previously targeted with CAR-T cells,as well as the CSC markers that may be used as possible targets for CAR-T cell therapy in the future.Furthermore,we will detail the most important obstacles against CART cell therapy and suggest solutions.

慢性淋巴细胞白血病靶向治疗的研究进展

慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)是小B细胞淋巴瘤和白血病的一种,也是B细胞克隆增殖性肿瘤。该病具有明显的异质性,大多数患者的病程趋于惰性,但目前仍不可治愈。异常的信号转导机制是CLL发病机制中不可或缺的。在CLL中,常见的异常信号通路包括B细胞受体信号、细胞凋亡、核因子κB(nuclear factor kappa-B,NF-κB)信号以及Notch信号通路等。针对这些信号通路,研发了一系列的靶向药物,如布鲁顿酪氨酸激酶抑制剂(伊布替尼、泽布替尼)、磷酸化磷脂酰肌醇3激酶抑制剂(杜韦利西布)、B细胞淋巴瘤2抑制剂(维奈克拉)等,在临床上显著改变了患者的预后。其他靶向药物如fenebrutinib、nemtabrutinib、厄布利塞等,还有免疫肿瘤学和T细胞工程领域发展的嵌合抗原受体T细胞疗法,目前尚在临床试验阶段。更加个体化的治疗方式正在探索,未来可能成为潜在的治疗选择。该文对CLL领域的相关文献进行梳理,就CLL分子机制及靶向治疗的最新研究进行综述。

Anti-BCMA CAR-T Cell Therapy in Relapsed or Refractory Multiple Myeloma Patients with Impaired Renal Function

Anti-B cell maturation antigen(BCMA)chimeric antigen receptor(CAR)T-cell therapyis effective and well-tolerated for refractory or relapsed multiple myeloma(RRMM).The purposcof the present study was to analyze efficacy in RRMM patients with renal impairment treated byanti-BCMA CAR-T cell therapy.A total of 59 RRMM patients were selected,and divided intoimpaired renal function(lRF)group[basclinc cstimated giomerular filtration rate(eSFR)<90 m/min/1.73 m^2(n=18)]and normal renal function(NRF)group(baseline eGFR≥90 mL/min/1.73 m,n=41).For patients with IRF,eGFR at the 6th month post-CAR-T cells infusion was significantlyhigher than the baseline(P<0.05).The multivariate analysis showed that light chain type and beta-2 micro-globulin(bcta-2M)were associated factors with the decrease of serum creatinine.Medianprogression-free survival(PFS)in the NRF group and IRF group was 266 days and 181 daysrespectively.Overall survival(OS)in the NRF group and lRF group was 877 days and 238 daysrespectively.There was no significant difference in the objective response rate(ORR)between thelRF group and the NRF group.It is suggested that CAR-T cells therapy could improve the renalfunction during the treatment of RRMM.The renal function could be more significantly improvedin RRMM patients with light chain type than with other types.

过继性T细胞疗法在头颈部鳞癌中的研究进展

过继性T细胞疗法(adoptive T cell therapy,ACT)是一种高度个性化的抗肿瘤治疗方法,临床研究正在迅速发展。研究表明,ACT疗法可以通过增加T细胞数量,增强对肿瘤组织的特异性和反应性,从而克服肿瘤免疫缺陷抑制的产生。ACT疗法目前有3种主要模式:肿瘤浸润淋巴细胞(TILs)、嵌合抗原受体T细胞(CAR-T)和T细胞受体工程化T细胞(TCR-T)治疗。本文对ACT疗法的分类及研究进展进行综述,包括TILs、CAR-T、TCR-T以及基于类器官共培养的过继性T淋巴细胞免疫治疗,探讨ACT作为头颈部鳞癌治疗方式的应用前景。

基于多链结构的CD30 CAR-T细胞的抗肿瘤作用研究

目的基于衔接蛋白DAP12的多链嵌合抗原受体T细胞(CAR-T)开发靶向CD30的CAR-T细胞药物,研究CD30 CAR-T对霍奇金淋巴瘤肿瘤细胞的体外和体内临床前药效。方法通过基因合成和分子克隆技术,设计构建靶向CD30的CAR质粒,进行慢病毒包装,将得到的慢病毒转染T细胞,其中靶向CD30的多链CAR-T为CD30-KIRS2/Dap12-BB组,单链二代CAR-T为CD30-41BBζ组,未做病毒侵染的T细胞为NTD组,利用流式细胞术检测CAR阳性率情况,通过乳酸脱氢酶(LDH)释放检测细胞的杀伤活性,采用酶联免疫吸附试验(ELISA)检测细胞因子干扰素γ(IFN-γ)的分泌水平,进一步通过小鼠异种移植瘤模型检测CD30 CAR-T在小鼠体内抗肿瘤活性。结果靶向CD30的多链CAR-T和单链二代CAR-T进行对比,研究发现多链CAR-T与单链CAR-T的杀瘤作用相似。但值得注意的是,多链CAR-T的IFN-γ分泌水平更高(P<0.001)。更重要的是,在小鼠的肿瘤模型实验中,多链CAR-T实现了肿瘤的完全消退。结论靶向CD30的多链CAR-T在抗肿瘤活性方面优于传统单链CAR-T。

复发难治弥漫大B细胞淋巴瘤的二线治疗:自体造血干细胞移植或嵌合抗原受体T细胞治疗?

弥漫性大B细胞淋巴瘤(DLBCL)是最常见的侵袭性淋巴瘤亚型。一线规范的治疗后,60%的患者可以实现治愈,但是仍有40%的患者复发或者难治,预后不佳。挽救性化疗联合自体造血干细胞移植(ASCT)是化疗敏感患者的标准二线治疗方案。然而,伴随着新的治疗方式,如嵌合抗原受体T细胞疗法、双特异性抗体、靶向药物等的出现,标准二线治疗方案受到一定的挑战,尤其对于挽救性化疗不够敏感的患者。本文对目前复发难治DLBCL的二线治疗的安全性和疗效及适应证进行综述,以探讨复发难治DLBCL的最佳治疗选择。