Improving T-cell therapy for relapsed EBV-negative Hodgkin lymphoma by targeting upregulated MAGE-A4

MAGE-A4-Responsive Plasma Cells Promote Non-Small Cell Lung Cancer

Adaptive immunity is critical to eliminate malignant cells, while multiple tumor-intrinsic factors can alter this protective function. Melanoma antigen-A4 (MAGE-A4), a cancer-testis antigen, is expressed in several solid tumors and correlates with poor survival in non-small cell lung cancer (NSCLC), but its role in altering antitumor immunity remains unclear. We found that expression of MAGE-A4 was highly associated with the loss of PTEN , a tumor suppressor, in human NSCLC. Here we show that constitutive expression of human MAGE-A4 combined with the loss of Pten in mouse airway epithelial cells results in metastatic adenocarcinoma enriched in CD138 + CXCR4 + plasma cells, predominantly expressing IgA. Consistently, human NSCLC expressing MAGE-A4 showed increased CD138 + IgA + plasma cell density surrounding tumors. The abrogation of MAGE-A4-responsive plasma cells (MARPs) decreased tumor burden, increased T cell infiltration and activation, and reduced CD163 + CD206 + macrophages in mouse lungs. These findings suggest MAGE-A4 promotes NSCLC tumorigenesis, in part, through the recruitment and retention of IgA + MARPs in the lungs.

Comparative responses to demethylating therapy in animal models of osteosarcoma

Background

The demethylating agent decitabine (DAC) effectively inhibits tumor growth and metastasis by targeting ESR1 methylation to restore estrogen receptor alpha (ERα) signaling and promoting cellular differentiation in models of human osteosarcoma (OSA). Whether this pathway can be targeted in canine OSA patients is unknown.

Methods

Canine OSA tumor samples were tested for ERα expression and ESR1 promoter methylation. Human (MG63.3) and canine (MC-KOS) OSA cell lines and murine xenografts were treated with DAC in vitro and in vivo, respectively. Samples were assessed using mRNA sequencing and tissue immunohistochemistry.

Results

ESR1 is methylated in a subset of canine OSA patient samples and the MC-KOS cell line. DAC treatment led to enhanced differentiation as demonstrated by increased ALPL expression, and suppressed tumor growth in vitro and in vivo. Metastatic progression was inhibited, particularly in the MG63.3 model, which expresses higher levels of DNA methyltransferases DNMT1 and 3B. DAC treatment induced significant alterations in immune response and cell cycle pathways.

Conclusion

DAC treatment activates ERα signaling, promotes bone differentiation, and inhibits tumor growth and metastasis in human and canine OSA. Additional DAC-altered pathways and species- or individual-specific differences in DNMT expression may also play a role in DAC treatment of OSA.

The Melanoma-Associated Antigen Family A (MAGE-A): A Promising Target for Cancer Immunotherapy?

Early efforts to identify tumor-associated antigens over the last decade have provided unique cancer epitopes for targeted cancer therapy. MAGE-A proteins are a subclass of cancer/testis (CT) antigens that are presented on the cell surface by MHC class I molecules as an immune-privileged site. This is due to their restricted expression to germline cells and a wide range of cancers, where they are associated with resistance to chemotherapy, metastasis, and cancer cells with an increasing potential for survival. This makes them an appealing candidate target for designing an effective and specific immunotherapy, thereby suggesting that targeting oncogenic MAGE-As with cancer vaccination, adoptive T-cell transfer, or a combination of therapies would be promising. In this review, we summarize and discuss previous and ongoing (pre-)clinical studies that target these antigens, while bearing in mind the benefits and drawbacks of various therapeutic strategies, in order to speculate on future directions for MAGE-A-specific immunotherapies.

Inhibitory effect and related mechanism of decitabine combined with gemcitabine on proliferation of NK/T cell lymphoma cells

Background: EBV-associated lymphoma is a neoplasm with a poor prognosis, highly aggressive, and progressive rapidly. There is no standard clinical treatment protocol. Decitabine and gemcitabine are known to have anticancer properties against cells of various cancer, respectively. However, the effect of the combination medication on NK/T cell lymphoma cells and potential mechanisms have not been thoroughly investigated. Methods: Human NK/T cell lymphoma cells NK92MI were treated with decitabine and gemcitabine alone or in combination. Experiments, including the Cell Counting Kit-8 and flow cytometry, were performed to investigate how the combination of decitabine and gemcitabine affects the biological behavior of NK92MI cells in vitro. mRNA sequencing, RT-PCR, and western blotting were used to detect changes in the related signal pathway, mRNA, and protein expressions. Results: Decitabine and gemcitabine significantly inhibited the viability and proliferation of NK92MI cells in a dose-dependent manner. The combination index was less than 1 after treating with two drugs, which was a significant synergistic effect. The decitabine concentration with the best synergistic effect was 4.046 µM, and the gemcitabine concentration was 0.005 µM. Flow cytometry showed that combining two drugs could significantly promote apoptosis and arrest the cell cycle at the S phase. In the combined DAC and GEM group, caspase3 protein levels were higher than in either group alone or the control group. The transcriptome sequence, KEGG, and PPI analysis showed that the differential genes after combined treatment were mainly enriched in signal pathways related to cell proliferation, adhesion, and migration compared with using alone and control groups. Based on the sequencing results, we further investigated the role of DAC and GEM in ferroptosis-related signaling molecules using RT-PCR and Western blot techniques. RT-PCR and western blotting showed that the expression levels of HMOX1 and EBV cleavage gene BRLF1 were higher in the group with combined DAC and GEM than in the group alone and the control group, while the protein and mRNA expression levels of SLC7A11 were lower than the others. In addition, the GPX4 protein expression level in the combination group was lower than in the drug-alone and control groups. In addition, the combination treatment increased the ROS level of NK92MI cells. Conclusion: Our current findings suggested that decitabine had an inhibitory effect on the proliferation of NK92MI cells when co-treated with gemcitabine. This combination may increase the expression of ferroptosis-related signaling molecules, thus inhibiting the proliferation of NK92MI cells. It also promoted apoptosis in NK/T cell lymphoma. For patients with NK/T cell lymphoma, this novel combination may provide clinical benefits.

Leveraging epigenetics to enhance the efficacy of cancer-testis antigen: a potential candidate for immunotherapy

Ovarian cancer is the most lethal gynecological malignancy in women. The phenotype is characterized by delayed diagnosis, recurrence and drug resistance. Inherent immunogenicity potential, oncogenic function and expression of cancer-testis/germline antigen (CTA) in ovarian cancer render them a potential candidate for immunotherapy. Revolutionary clinical findings indicate that tumor antigen-mediated T-cell and dendritic cell-based immunotherapeutic approaches provide an excellent strategy for targeting tumors. Currently, dendritic cell vaccination for the treatment of B-cell lymphoma and CTA-based T-cell receptor transduced T-cell therapy involving MAGE-A4 and NY-ESO-1 are well documented and shown to be effective. This review highlighted the mechanical aspects of epigenetic drugs that can elicit a CTA-based humoral and cellular immune response and implicate T-cell and dendritic cell-based immunotherapeutic approaches.

How to Slow down the Ticking Clock: Age-Associated Epigenetic Alterations and Related Interventions to Extend Life Span

Epigenetic alterations pose one major hallmark of organismal aging. Here, we provide an overview on recent findings describing the epigenetic changes that arise during aging and in related maladies such as neurodegeneration and cancer. Specifically, we focus on alterations of histone modifications and DNA methylation and illustrate the link with metabolic pathways. Age-related epigenetic, transcriptional and metabolic deregulations are highly interconnected, which renders dissociating cause and effect complicated. However, growing amounts of evidence support the notion that aging is not only accompanied by epigenetic alterations, but also at least in part induced by those. DNA methylation clocks emerged as a tool to objectively determine biological aging and turned out as a valuable source in search of factors positively and negatively impacting human life span. Moreover, specific epigenetic signatures can be used as biomarkers for age-associated disorders or even as targets for therapeutic approaches, as will be covered in this review. Finally, we summarize recent potential intervention strategies that target epigenetic mechanisms to extend healthy life span and provide an outlook on future developments in the field of longevity research.

MAGEA4 Coated Extracellular Vesicles Are Stable and Can Be Assembled In Vitro

Extracellular vesicles (EVs) are valued candidates for the development of new tools for medical applications. Vesicles carrying melanoma-associated antigen A (MAGEA) proteins, a subfamily of cancer-testis antigens, are particularly promising tools in the fight against cancer. Here, we have studied the biophysical and chemical properties of MAGEA4-EVs and show that they are stable under common storage conditions such as keeping at +4 °C and -80 °C for at least 3 weeks after purification. The MAGEA4-EVs can be freeze-thawed two times without losing MAGEA4 in detectable quantities. The attachment of MAGEA4 to the surface of EVs cannot be disrupted by high salt concentrations or chelators, but the vesicles are sensitive to high pH. The MAGEA4 protein can bind to the surface of EVs in vitro, using robust passive incubation. In addition, EVs can be loaded with recombinant proteins fused to the MAGEA4 open reading frame within the cells and also in vitro. The high stability of MAGEA4-EVs ensures their potential for the development of EV-based anti-cancer applications.

Causes, effects, and clinical implications of perturbed patterns within the cancer epigenome

Somatic mutations accumulating over a patient's lifetime are well-defined causative factors that fuel carcinogenesis. It is now clear, however, that epigenomic signature is also largely perturbed in many malignancies. These alterations support the transcriptional program crucial for the acquisition and maintenance of cancer hallmarks. Epigenetic instability may arise due to the genetic mutations or transcriptional deregulation of the proteins implicated in epigenetic signaling. Moreover, external stimulation and physiological aging may also participate in this phenomenon. The epigenomic signature is frequently associated with a cell of origin, as well as with tumor stage and differentiation, which all reflect its high heterogeneity across and within various tumors. Here, we will overview the current understanding of the causes and effects of the altered and heterogeneous epigenomic landscape in cancer. We will focus mainly on DNA methylation and post-translational histone modifications as the key regulatory epigenetic signaling marks. In addition, we will describe how this knowledge is translated into the clinic. We will particularly concentrate on the applicability of epigenetic alterations as biomarkers for improved diagnosis, prognosis, and prediction. Finally, we will also review current developments regarding epi-drug usage in clinical and experimental settings.

Frontiers in cancer immunotherapy-a symposium report

Cancer immunotherapy has dramatically changed the approach to cancer treatment. The aim of targeting the immune system to recognize and destroy cancer cells has afforded many patients the prospect of achieving deep, long-term remission and potential cures. However, many challenges remain for achieving the goal of effective immunotherapy for all cancer patients. Checkpoint inhibitors have been able to achieve long-term responses in a minority of patients, yet improving response rates with combination therapies increases the possibility of toxicity. Chimeric antigen receptor T cells have demonstrated high response rates in hematological cancers, although most patients experience relapse. In addition, some cancers are notoriously immunologically "cold" and typically are not effective targets for immunotherapy. Overcoming these obstacles will require new strategies to improve upon the efficacy of current agents, identify biomarkers to select appropriate therapies, and discover new modalities to expand the accessibility of immunotherapy to additional tumor types and patient populations.

Characteristics of a Novel Target Antigen Against Myeloma Cells for Immunotherapy

Despite the availability of therapeutic treatments, multiple myeloma is an incurable haematological disorder. In this study, we aimed to clarify the role of CXorf48 as a therapeutic target in multiple myeloma. Based on a previously identified HLA-A*24:02-restiricted epitope from this novel cancer/testis antigen, we characterized the activities of cytotoxic T lymphocytes (CTLs) specific to this antigen against myeloma cells and evaluated the effects of demethylating agents in increasing antigen expression and enhancing the cytotoxic activity of CTLs. CXorf48 expression was examined by reverse transcription polymerase chain reaction (RT-PCR) using nine myeloma cell lines. Cell lines with low CXorf48 expression were treated by demethylating agents (DMAs), 5-azacytidine (5-aza), and 5-aza-2’-deoxycytidine (DAC) to evaluate gene expression using quantitative RT-PCR. Furthermore, CXorf48-specific CTLs were induced from peripheral blood mononuclear cells of HLA-A*24:02-positive healthy donors to evaluate antigen recognition using ELISpot and ⁵¹Cr cytotoxicity assays. CXorf48 was widely expressed in myeloma cells, and gene expression was significantly increased by DMAs. Furthermore, CXorf48-specific CTLs recognized DMA-treated myeloma cells. These findings suggest that CXorf48 is a useful target for immunotherapy, such as vaccination, in combination with demethylating agents for the treatment of patients with myeloma.

Targeting the epigenetic regulation of antitumour immunity

Dysregulation of the epigenome drives aberrant transcriptional programmes that promote cancer onset and progression. Although defective gene regulation often affects oncogenic and tumour-suppressor networks, tumour immunogenicity and immune cells involved in antitumour responses may also be affected by epigenomic alterations. This could have important implications for the development and application of both epigenetic therapies and cancer immunotherapies, and combinations thereof. Here, we review the role of key aberrant epigenetic processes - DNA methylation and post-translational modification of histones - in tumour immunogenicity, as well as the effects of epigenetic modulation on antitumour immune cell function. We emphasize opportunities for small-molecule inhibitors of epigenetic regulators to enhance antitumour immune responses, and discuss the challenges of exploiting the complex interplay between cancer epigenetics and cancer immunology to develop treatment regimens combining epigenetic therapies with immunotherapies.

Adoptive Immunotherapy with Antigen-Specific T Cells Expressing a Native TCR

Although T cells genetically modified with chimeric antigen receptors became the first immune effector product to obtain FDA approval, T-cell products that recognize their antigenic targets through their native receptors have also produced encouraging responses. For instance, T cells recognizing immunogenic viral antigens are effective when infused in immunosuppressed patients. A large number of tumor antigens are also expressed on nonviral tumors, but these antigens are less immunogenic. Many tumors can evade a transferred immune response by producing variants, which have lost the targeted antigens, or inhibitory molecules that recruit suppressive cells, impeding persistence and function of immune effectors. Nevertheless, infusion of antigen-specific T cells has been well-tolerated, and clinical responses have been consistently associated with immune activity against tumor antigens and epitope spreading. To overcome some of the obstacles mentioned above, current research is focused on defining ex vivo culture conditions that promote in vivo persistence and activity of infused antigen-specific T cells. Combinations with immune checkpoint inhibitors or epigenetic modifiers to improve T-cell activity are also being evaluated in the clinic. Antigen-specific T cells may also be manufactured to overcome tumor evasion mechanisms by targeting multiple antigens and engineered to be resistant to inhibitory factors, such as TGFβ, or to produce the cytokines that are essential for T-cell expansion and sustained antitumor activity. Here, we discuss the use of T cells specific to tumor antigens through their native receptors and strategies under investigation to improve antitumor responses.

Overcoming Heterogeneity of Antigen Expression for Effective CAR T Cell Targeting of Cancers

Chimeric antigen receptor (CAR) gene-modified T cells (CAR T cells) can eradicate B cell malignancies via recognition of surface-expressed B lineage antigens. Antigen escape remains a major mechanism of relapse and is a key barrier for expanding the use of CAR T cells towards solid cancers with their more diverse surface antigen repertoires. In this review we discuss strategies by which cancers become amenable to effective CAR T cell therapy despite heterogeneous phenotypes. Pharmaceutical approaches have been reported that selectively upregulate individual target antigens on the cancer cell surface to sensitize antigen-negative subclones for recognition by CARs. In addition, advanced T cell engineering strategies now enable CAR T cells to interact with more than a single antigen simultaneously. Still, the choice of adequate targets reliably and selectively expressed on the cell surface of tumor cells but not normal cells, ideally by driving tumor growth, is limited, and even dual or triple antigen targeting is unlikely to cure most solid tumors. Innovative receptor designs and combination strategies now aim to recruit bystander cells and alternative cytolytic mechanisms that broaden the activity of CAR-engineered T cells beyond CAR antigen-dependent tumor cell recognition.

Genetically Modified T-Cell Therapy for Osteosarcoma: Into the Roaring 2020s

T-cell immunotherapy may offer an approach to improve outcomes for patients with osteosarcoma who fail current therapies. In addition, it has the potential to reduce treatment-related complications for all patients. Generating tumor-specific T cells with conventional antigen-presenting cells ex vivo is time-consuming and often results in T-cell products with a low frequency of tumor-specific T cells. Furthermore, the generated T cells remain sensitive to the immunosuppressive tumor microenvironment. Genetic modification of T cells is one strategy to overcome these limitations. For example, T cells can be genetically modified to render them antigen specific, resistant to inhibitory factors, or increase their ability to home to tumor sites. Most genetic modification strategies have only been evaluated in preclinical models; however, early clinical phase trials are in progress. In this chapter, we will review the current status of gene-modified T-cell therapy with special focus on osteosarcoma, highlighting potential antigenic targets, preclinical and clinical studies, and strategies to improve current T-cell therapy approaches.

Immunotherapy of Relapsed and Refractory Solid Tumors With Ex Vivo Expanded Multi-Tumor Associated Antigen Specific Cytotoxic T Lymphocytes: A Phase I Study

PURPOSE

Tumor-associated antigen cytotoxic T cells (TAA-Ts) represent a new, potentially effective and nontoxic therapeutic approach for patients with relapsed or refractory solid tumors. In this first-in-human trial, we investigated the safety of administering TAA-Ts that target Wilms tumor gene 1, preferentially expressed antigen of melanoma, and survivin to patients with relapsed/refractory solid tumors.

MATERIALS AND METHODS

TAA-T products were generated from autologous peripheral blood and infused over three dose levels: 1, 2, and 4 × 10⁷ cells/m². Patients were eligible for up to eight infusions administered 4 to 7 weeks apart. We assessed dose limiting toxicity during the first 45 days after infusion. Disease response was determined within the context of a phase I trial.

RESULTS

There were no dose-limiting toxicities. Of 15 evaluable patients, 11 (73%) with stable disease or better at day 45 postinfusion were defined as responders. Six responders remain without progression at a median of 13.9 months (range, 4.1 to 19.9 months) after initial TAA-Ts. Patients who were treated at the highest dose level showed the best clinical outcomes, with a 6-month progression-free survival of 73% after TAA-T infusion compared with a 38% 6-month progression-free survival with prior therapy. Antigen spreading and a reduction in circulating tumor-associated antigens using digital droplet polymerase chain reaction was observed in patients after TAA-T infusion.

CONCLUSION

TAA-Ts safely induced disease stabilization, prolonged time to progression, and were associated with antigen spreading and a reduction in circulating tumor-associated antigen DNA levels in patients with relapsed/refractory solid tumors without lymphodepleting chemotherapy before infusion. TAA-Ts are a promising new treatment approach for patients with solid tumors.

T-cell therapies for T-cell lymphoma

T-cell lymphomas represent a subpopulation of non-Hodgkin lymphomas with poor outcomes when treated with conventional chemotherapy. A variety of novel agents have been introduced as new treatment strategies either as first-line treatment or in conjunction with chemotherapy. Immunotherapy has been demonstrated to be a promising area for new therapeutics, including monoclonal antibodies and adoptive cellular therapeutics. T-cell therapeutics have been shown to have significant success in the treatment of B-cell malignancies and are rapidly expanding as potential treatment options for other cancers including T-cell lymphomas. Although treating T-cell lymphomas with T-cell therapeutics has unique challenges, multiple targets are currently being studied both preclinically and in clinical trials.

Cancer-testis antigens in ovarian cancer: implication for biomarkers and therapeutic targets

Ovarian cancer remains the most fatal gynecologic malignancy worldwide due to delayed diagnosis as well as recurrence and drug resistance. Thus, the development of new tumor-related molecules with high sensitivity and specificity to replace or supplement existing tools is urgently needed. Cancer-testis antigens (CTAs) are exclusively expressed in normal testis tissues but abundantly found in several types of cancers, including ovarian cancer. Numerous novel CTAs have been identified by high-throughput sequencing techniques, and some aberrantly expressed CTAs are associated with ovarian cancer initiation, clinical outcomes and chemotherapy resistance. More importantly, CTAs are immunogenic and may be novel targets for antigen-specific immunotherapy in ovarian cancer. In this review, we attempt to characterize the expression of candidate CTAs in ovarian cancer and their clinical significance as biomarkers, activation mechanisms, function in malignant phenotypes and applications in immunotherapy.

Decitabine Enhances Vγ9Vδ2 T Cell-Mediated Cytotoxic Effects on Osteosarcoma Cells via the NKG2DL-NKG2D Axis

γδ T cell-based immunotherapy for osteosarcoma (OS) has shown limited success thus far. DNA-demethylating agents not only induce tumor cell death but also have an immunomodulatory function. In this study, we have assessed the potential benefit of combining decitabine (DAC, a DNA demethylation drug) and γδ T cells for OS immunotherapy. DAC increased the expression of natural killer group 2D (NKG2D) ligands (NKG2DLs), including major histocompatibility complex class I-related chains B (MICB) and UL16-binding protein 1 (ULBP1), on the OS cell surface, making the cells more sensitive to recognition and destruction by cytotoxic γδ T cells. The upregulation of MICB and ULBP1 was due to promoter DNA demethylation. Importantly, the killing of OS cells by γδ T cells was partially reversed by blocking the NKG2D receptor, suggesting that the γδ T cell-mediated cytolysis of DAC-pretreated OS cells was mainly dependent on the NKG2D-NKG2DL axis. The in vivo results were consistent with the in vitro results. In summary, DAC could upregulate MICB and ULBP1 expression in OS cells, and combination treatment involving γδ T cell immunotherapy and DAC could be used to enhance the cytotoxic killing of OS cells by γδ T cells.

Beyond Chemotherapy: Checkpoint Inhibition and Cell-Based Therapy in Non-Hodgkin Lymphoma

Immune-based treatment strategies, such as checkpoint inhibition and chimeric antigen receptor (CAR) T cells, have started a new frontier for treatment in non-Hodgkin lymphoma (NHL). Checkpoint inhibition has been most successful in Hodgkin lymphoma, where higher expression of PD-L1 is correlated with better overall response rate. Combinations of checkpoint inhibition with various chemotherapy or biologics are in clinical trials, with initially promising results and manageable safety profiles. CAR T-cell therapies that target CD19 are a promising and attractive therapy for B-cell NHLs, with a product approved by the US Food and Drug Administration in 2017. Changes in the target, hinge, or costimulatory domain can dramatically alter the persistence and efficacy of the CAR T cells. The ZUMA trials from Kite used CD19-(CD28z) CAR T cells, whereas the TRANSCEND studies from Juno and the JULIET studies from Novartis used CD19-(4-1BBz) CARs. Despite the recent successes with CAR T-cell clinical trials, major concerns associated with this therapy include cytokine release syndrome, potential neurotoxicities, B-cell aplasia, loss of tumor antigen leading to relapse, and cost and accessibility of the treatment. Although first-generation CAR T-cell therapies have failed in solid malignancies, newer second- and third-generation CAR T cells that target antigens other than CD19 (such as mesothelin or B-cell maturation antigen) are being studied in clinical trials for treatment of lung cancer or multiple myeloma. Overall, immune-based treatment strategies have given oncologists and patients hope when there used to be none, as well as a new basket of tools yet to come with further research and development.

Biology of classical Hodgkin lymphoma: implications for prognosis and novel therapies

Hodgkin lymphoma is considered a prime example of treatment success, with cure rates exceeding 80% using modern combined modality therapies. However, especially in adolescents and young adults, treatment-related toxicity and long-term morbidity still represent persistent challenges. Moreover, outcomes in patients with relapsed or refractory disease remain unfavorable in the era of high-dose chemotherapy and stem-cell transplantation. Hence, there is a high demand for novel and innovative alternative treatment approaches. In recent years, many new therapeutic agents have emerged from preclinical and clinical studies that target molecular hallmarks of Hodgkin lymphoma, including the aberrant phenotype of the tumor cells, deregulated oncogenic pathways, and immune escape. The antibody-drug conjugate brentuximab vedotin and immune checkpoint inhibitors have already shown great success in patients with relapsed/refractory disease, leading to US Food and Drug Administration approval and new trials testing these agents in various clinical settings. The expanding knowledge and understanding of Hodgkin lymphoma biology and disease progression, as well as the development of robust tools for biomarker-driven risk stratification and therapeutic decision making, continue to be fundamentally important for the success of these and other novel agents. We anticipate that the availability and clinical implementation of novel molecular assays will be instrumental in an era of rapid shifts in the treatment landscape of this disease. Here, we review the current knowledge of Hodgkin lymphoma pathobiology, highlighting the related development of novel treatment strategies and prognostic models that hold the promise to continually challenge and change the current standard of care in classical Hodgkin lymphoma.

Human CD3+ T-Cells with the Anti-ERBB2 Chimeric Antigen Receptor Exhibit Efficient Targeting and Induce Apoptosis in ERBB2 Overexpressing Breast Cancer Cells

Breast cancer is a common malignancy among women. The innate and adaptive immune responses failed to be activated owing to immune modulation in the tumour microenvironment. Decades of scientific study links the overexpression of human epidermal growth factor receptor 2 (ERBB2) antigen with aggressive tumours. The Chimeric Antigen Receptor (CAR) coding for specific tumour-associated antigens could initiate intrinsic T-cell signalling, inducing T-cell activation, and cytotoxic activity without the need for major histocompatibility complex recognition. This renders CAR as a potentially universal immunotherapeutic option. Herein, we aimed to establish CAR in CD3+ T-cells, isolated from human peripheral blood mononucleated cells that could subsequently target and induce apoptosis in the ERBB2 overexpressing human breast cancer cell line, SKBR3. Constructed CAR was inserted into a lentiviral plasmid containing a green fluorescent protein tag and produced as lentiviral particles that were used to transduce activated T-cells. Transduced CAR-T cells were then primed with SKBR3 cells to evaluate their functionality. Results showed increased apoptosis in SKBR3 cells co-cultured with CAR-T cells compared to the control (non–transduced T-cells). This study demonstrates that CAR introduction helps overcome the innate limitations of native T-cells leading to cancer cell apoptosis. We recommend future studies should focus on in vivo cytotoxicity of CAR-T cells against ERBB2 expressing tumours.

Adoptive Immunotherapy For Leukemia With Ex vivo Expanded T Cells

The development of novel T cell therapies to target leukemia has facilitated the translation of this approach for hematologic malignancies. Different methods of manufacturing leukemia-specific T cells have evolved, along with additional measures to increase the safety of this therapy. This is an overview of expanded T cell therapeutics with a focus on how the manufacturing strategies have been refined, and where the research is heading.

MAGE-C2-Specific TCRs Combined with Epigenetic Drug-Enhanced Antigenicity Yield Robust and Tumor-Selective T Cell Responses

Adoptive T cell therapy has shown significant clinical success for patients with advanced melanoma and other tumors. Further development of T cell therapy requires improved strategies to select effective, yet nonself-reactive, TCRs. In this study, we isolated 10 TCR sequences against four MAGE-C2 (MC2) epitopes from melanoma patients who showed clinical responses following vaccination that were accompanied by significant frequencies of anti-MC2 CD8 T cells in blood and tumor without apparent side effects. We introduced these TCRs into T cells, pretreated tumor cells of different histological origins with the epigenetic drugs azacytidine and valproate, and tested tumor and self-reactivities of these TCRs. Pretreatment of tumor cells upregulated MC2 gene expression and enhanced recognition by T cells. In contrast, a panel of normal cell types did not express MC2 mRNA, and similar pretreatment did not result in recognition by MC2-directed T cells. Interestingly, the expression levels of MC2, but not those of CD80, CD86, or programmed death-ligand 1 or 2, correlated with T cell responsiveness. One of the tested TCRs consistently recognized pretreated MC2(+) cell lines from melanoma, head and neck, bladder, and triple-negative breast cancers but showed no response to MHC-eluted peptides or peptides highly similar to MC2. We conclude that targeting MC2 Ag, combined with epigenetic drug-enhanced antigenicity, allows for significant and tumor-selective T cell responses.

DNA methyltransferase inhibition increases efficacy of adoptive cellular immunotherapy of murine breast cancer

Adoptive T cell immunotherapy is a promising approach to cancer treatment that currently has limited clinical applications. DNA methyltransferase inhibitors (DNAMTi) have known potential to affect the immune system through multiple mechanisms that could enhance the cytotoxic T cell responses, including: upregulation of tumor antigen expression, increased MHC class I expression, and blunting of myeloid derived suppressor cells (MDSCs) expansion. In this study, we have investigated the effect of combining the DNAMTi, decitabine, with adoptive T cell immunotherapy in the murine 4T1 mammary carcinoma model. We found that expression of neu, MHC class I molecules, and several murine cancer testis antigens (CTA) was increased by decitabine treatment of 4T1 cells in vitro. Decitabine also increased expression of multiple CTA in two human breast cancer cell lines. Decitabine-treated 4T1 cells stimulated greater IFN-gamma release from tumor-sensitized lymphocytes, implying increased immunogenicity. Expansion of CD11b + Gr1 + MDSC in 4T1 tumor-bearing mice was significantly diminished by decitabine treatment. Decitabine treatment improved the efficacy of adoptive T cell immunotherapy in mice with established 4T1 tumors, with greater inhibition of tumor growth and an increased cure rate. Decitabine may have a role in combination with existing and emerging immunotherapies for breast cancer.

The immune microenvironment in Hodgkin lymphoma: T cells, B cells, and immune checkpoints

Classical Hodgkin lymphoma is curable in the majority of cases with chemotherapy and/or radiation. However, 15-20% of patients ultimately relapse and succumb to their disease. Pathologically, classical Hodgkin lymphoma is characterized by rare tumor-initiating Reed-Sternberg cells surrounded by a dense immune microenvironment. However, the role of the immune microenvironment, particularly T and B cells, in either promoting or restricting Classical Hodgkin lymphoma growth remains undefined. Recent dramatic clinical responses seen using monoclonal antibodies against PD-1, a cell surface receptor whose primary function is to restrict T cell activation, have reignited questions regarding the function of the adaptive immune system in classical Hodgkin lymphoma. This review summarizes what is known regarding T cells, B cells, and immune checkpoints in classical Hodgkin lymphoma.

Improving cancer immunotherapy with DNA methyltransferase inhibitors

Immunotherapy confers durable clinical benefit to melanoma, lung, and kidney cancer patients. Challengingly, most other solid tumors, including ovarian carcinoma, are not particularly responsive to immunotherapy, so combination with a complementary therapy may be beneficial. Recent findings suggest that epigenetic modifying drugs can prime antitumor immunity by increasing expression of tumor-associated antigens, chemokines, and activating ligands by cancer cells as well as cytokines by immune cells. This review, drawing from both preclinical and clinical data, describes some of the mechanisms of action that enable DNA methyltransferase inhibitors to facilitate the establishment of antitumor immunity.

T-cell therapies for HIV: Preclinical successes and current clinical strategies

Although antiretroviral therapy (ART) has been successful in controlling HIV infection, it does not provide a permanent cure, requires lifelong treatment, and HIV-positive individuals are left with social concerns such as stigma. The recent application of T cells to treat cancer and viral reactivations post-transplant offers a potential strategy to control HIV infection. It is known that naturally occurring HIV-specific T cells can inhibit HIV initially, but this response is not sustained in the majority of people living with HIV. Genetically modifying T cells to target HIV, resist infection, and persist in the immunosuppressive environment found in chronically infected HIV-positive individuals might provide a therapeutic solution for HIV. This review focuses on successful preclinical studies and current clinical strategies using T-cell therapy to control HIV infection and mediate a functional cure solution.

Oncogenic cancer/testis antigens: prime candidates for immunotherapy

Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer/testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic functions, including support of growth, survival and metastasis. This novel insight into the function of cancer/testis antigens has the potential to deliver more effective cancer vaccines. Moreover, immune targeting of oncogenic cancer/testis antigens in combination with conventional cytotoxic therapies or novel immunotherapies such as checkpoint blockade or adoptive transfer, represents a highly synergistic approach with the potential to improve patient survival.

T-cell and natural killer cell therapies for hematologic malignancies after hematopoietic stem cell transplantation: enhancing the graft-versus-leukemia effect

Hematopoietic stem cell transplantation has revolutionized the treatment of hematologic malignancies, but infection, graft-versus-host disease and relapse are still important problems. Calcineurin inhibitors, T-cell depletion strategies, and immunomodulators have helped to prevent graft-versus-host disease, but have a negative impact on the graft-versus-leukemia effect. T cells and natural killer cells are both thought to be important in the graft-versus-leukemia effect, and both cell types are amenable to ex vivo manipulation and clinical manufacture, making them versatile immunotherapeutics. We provide an overview of these immunotherapeutic strategies following hematopoietic stem cell transplantation, with discussions centered on natural killer and T-cell biology. We discuss the contributions of each cell type to graft-versus-leukemia effects, as well as the current research directions in the field as related to adoptive cell therapy after hematopoietic stem cell transplantation.

Emerging immunotherapy in pediatric lymphoma

Hodgkin and non-Hodgkin lymphoma collectively are the third most common cancer diagnosed in children each year. For children who relapse or have refractory disease, outcomes remain poor. Immunotherapy has recently emerged as a novel approach to treat hematologic malignancies. The field has been rapidly expanding over the past few years broadening its armamentarium which now includes monoclonal antibodies, antibody-drug conjugates and cellular therapies including bispecific T-cell engagers and chimeric antigen receptor-engineered T cells. Many of these agents are in their infancy stages and only beginning to make their mark on lymphoma treatment while others have begun to show promising efficacy in relapsed disease. In this review, the authors provide an overview of current and emerging immunotherapies in the field of pediatric lymphoma.

Adoptive T-cell therapies for refractory/relapsed leukemia and lymphoma: current strategies and recent advances

Despite significant advancements in the treatment and outcome of hematologic malignancies, prognosis remains poor for patients who have relapsed or refractory disease. Adoptive T-cell immunotherapy offers novel therapeutics that attempt to utilize the noted graft versus leukemia effect. While CD19 chimeric antigen receptor (CAR)-modified T cells have thus far been the most clinically successful application of adoptive T immunotherapy, further work with antigen specific T cells and CARs that recognize other targets have helped diversify the field to treat a broad spectrum of hematologic malignancies. This article will focus primarily on therapies currently in the clinical trial phase as well as current downfalls or limitations.

Myeloid-derived suppressor cells enhance the expression of melanoma-associated antigen A4 in a Lewis lung cancer murine model

The cancer-testis (CT) family of antigens are expressed in multiple types of malignant neoplasm and are silent in normal tissues, apart from the testis. Immunotherapy targeting CT antigens is a promising therapeutic strategy for treatment of solid tumors. One member of this family, melanoma-associated antigen A4 (MAGE-A4), has been demonstrated to be expressed in melanomas and lung cancer. Patients with tumors expressing the MAGE-A4 antigen exhibit specific cellular and humoral immune responses to the antigen, resulting in a favorable prognosis. Conversely, the expression of MAGE-A4 is associated with poor survival in lung cancer. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immunosuppressive cells, which are upregulated in the cancer microenvironment. Little is known regarding any potential correlation between the expression of MAGE-A4 antigens and the accumulation of MDSCs. The present study aimed to examine the association between circulating MDSC levels and MAGE-A4 expression in a mouse model of Lewis lung cancer. The expression of MAGE-A4 in tumor cells or tissues was evaluated using western blotting, while the percentage of MDSCs (CD11b⁺Gr-1⁺) in the blood was detected by flow cytometry. In addition, the suppressive capacity of MDSCs and the effectiveness of MDSC depletion were assessed in C57BL/6 tumor-bearing mice. MDSCs were demonstrated to upregulate MAGE-A4 expression via the phosphosphorylated-signal transducer and activator of transcription 3⁷⁰⁵ pathway, while depletion of MDSCs decreased the tumor growth rate, prolonged median survival and enhanced the recognition of MAGE-A4 by CD8⁺ T cells. These findings indicated that immunotherapeutic strategies involving induction of cytotoxic T lymphocytes that target MAGE-A4, in combination with MDSC depletion, may be an effective approach to immunotherapy for cancer types with high expression of MAGE-A4.

Induction of a specific CD8+ T-cell response to cancer/testis antigens by demethylating pre-treatment against osteosarcoma

Conventional non-surgical therapeutic regimens against osteosarcoma are subject to chemoresistance and tumor relapse, and immunotherapy may be promising for this tumor. However, it's hard to find satisfactory epitopes for immunotherapy against osteosarcoma. Cancer/testis antigens (CTAs), such as MAGE-A family and NY-ESO-1, the potential antigens that almost exclusively express in tumor cells and immune-privileged sites, have been found expressed in osteosarcoma also. Nevertheless, the expression of CTAs is downregulated in many tumors, constraining the application of immunotherapy. In this article, we demonstrate that the expression of MAGE-A family and NY-ESO-1 in osteosarcoma cells can be upregulated following treatment with demethylating agent 5-aza-2'-deoxycytidine and consequently induces a CTA specific CD8+ T-cell response against osteosarcoma in vitro and in vivo. The in vivo imaging was realized by using luciferase-transfected HOS cells and DiR labeled T-cells in severely combined immunodeficiency mouse models. Cytotoxic T cells specifically recognizing MAGE-A family and NY-ESO-1 clustered at the tumor site in mice pre-treated with DAC and resulted in tumor growth suppression, while it was not observed in mice without DAC pre-treatment. This study is important for more targeted therapeutic approaches and suggests that adoptive immunotherapy, combined with demethylating treatment, has the potential for non-surgical therapeutic strategy against osteosarcoma.

Directed T-cell therapies for leukemia and lymphoma after hematopoietic stem cell transplant: beyond chimeric antigen receptors

This review focuses on the recent advances utilizing adoptive T-cell immunotherapies for patients after hematopoietic stem cell transplant using T cells after autologous transplant to treat the highest risk patients. The particular emphasis is the use of T cells to treat leukemias and lymphomas with gene transfer and nongene transfer approaches to direct specificity to tumor associated antigens. In this review, we will highlight how these novel therapeutics can be successfully used to prevent or treat high-risk patients who relapse after hematopoietic stem cell transplant.

Decitabine Enhances Lymphocyte Migration and Function and Synergizes with CTLA-4 Blockade in a Murine Ovarian Cancer Model

The lack of second-line treatment for relapsed ovarian cancer necessitates the development of improved combination therapies. Targeted therapy and immunotherapy each confer clinical benefit, albeit limited as monotherapies. Ovarian cancer is not particularly responsive to immune checkpoint blockade, so combination with a complementary therapy may be beneficial. Recent studies have revealed that a DNA methyl transferase inhibitor, azacytidine, alters expression of immunoregulatory genes in ovarian cancer. In this study, the antitumor effects of a related DNA methyl transferase inhibitor, decitabine (DAC), were demonstrated in a syngeneic murine ovarian cancer model. Low-dose DAC treatment increases the expression of chemokines that recruit NK cells and CD8(+) T cells, promotes their production of IFNγ and TNFα, and extends the survival of mice bearing subcutaneous or orthotopic tumors. While neither DAC nor immune checkpoint blockade confers durable responses as a monotherapy in this model, the efficacy of anti-CTLA-4 was potentiated by combination with DAC. This combination promotes differentiation of naïve T cells into effector T cells and prolongs cytotoxic lymphocyte responses as well as mouse survival. These results suggest that this combination therapy may be worthy of further consideration for improved treatment of drug-resistant ovarian cancer.

Epigenetic potentiation of NY-ESO-1 vaccine therapy in human ovarian cancer

The cancer-testis/cancer-germline antigen NY-ESO-1 is a vaccine target in epithelial ovarian cancer (EOC), but its limited expression is a barrier to vaccine efficacy. As NY-ESO-1 is regulated by DNA methylation, we hypothesized that DNA methyltransferase (DNMT) inhibitors may augment NY-ESO-1 vaccine therapy. In agreement, global DNA hypomethylation in EOC was associated with the presence of circulating antibodies to NY-ESO-1. Pre-clinical studies using EOC cell lines showed that decitabine treatment enhanced both NY-ESO-1 expression and NY-ESO-1-specific CTL-mediated responses. Based on these observations, we performed a phase I dose-escalation trial of decitabine, as an addition to NY-ESO-1 vaccine and doxorubicin liposome (doxorubicin) chemotherapy, in 12 patients with relapsed EOC. The regimen was safe, with limited and clinically manageable toxicities. Both global and promoter-specific DNA hypomethylation occurred in blood and circulating DNAs, the latter of which may reflect tumor cell responses. Increased NY-ESO-1 serum antibodies and T cell responses were observed in the majority of patients, and antibody spreading to additional tumor antigens was also observed. Finally, disease stabilization or partial clinical response occurred in 6/10 evaluable patients. Based on these encouraging results, evaluation of similar combinatorial chemo-immunotherapy regimens in EOC and other tumor types is warranted.

Cytotoxic T lymphocytes for leukemia and lymphoma

This chapter focuses on the recent advances in adoptive T-cell immunotherapies, not only for patients after hematopoietic stem cell transplantation, but also in the autologous setting using T cells early in the disease process for the treatment of the highest-risk patients with leukemias and lymphomas. The particular emphasis is to highlight the role of T-cell therapies for hematologic malignancies using a non-gene-transfer approach to direct specificity, including the clinical use of T-cell therapies for EBV-associated lymphomas and strategies for targeting nonviral lymphoma- and leukemia-associated antigens.

Immunotherapy: opportunities, risks and future perspectives

This review is intended to reflect upon the current status and perspectives of cell-based immunotherapy at a time when the promise of extensive pre-clinical research has been translated into encouraging clinical responses. However, some of these have also been complicated by significant adverse reactions. As the field moves towards definitive late stage trials, with a growing interest from pharmaceutical companies, we realize that novel cell therapy strategies pose questions that are familiar to traditional drug development, along with new considerations due to the potential of T cells to persist long term and to expand after adoptive transfer. These questions address the safety of the product, the efficacy, the mode of action, and the anticipation of risks. From different perspectives, we intend to address exciting opportunities and safety concerns in current concepts of cellular immunotherapy.

Identification of miR-145 targets through an integrated omics analysis

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and protein synthesis. To characterize functions of miRNAs and to assess their potential applications, we carried out an integrated multi-omics analysis to study miR-145, a miRNA that has been shown to suppress tumor growth. We employed gene expression profiling, miRNA profiling and quantitative proteomic analysis of a pancreatic cancer cell line. In our transcriptomic analysis, overexpression of miR-145 was found to suppress the expression of genes that are implicated in development of cancer such as ITGA11 and MAGEA4 in addition to previously described targets such as FSCN1, YES1 and PODXL. Based on miRNA profiling, overexpression of miR-145 also upregulated other miRNAs including miR-124, miR-133b and miR-125a-3p, all of which are implicated in suppression of tumors and are generally co-regulated with miR-145 in other cancers. Using the SILAC system, we identified miR-145-induced downregulation of several oncoproteins/cancer biomarkers including SET, RPA1, MCM2, ABCC1, SPTBN1 and SPTLC1. Luciferase assay validation carried out on a subset of downregulated candidate targets confirmed them to be novel direct targets of miR-145. Overall, this multi-omics approach provided insights into miR-145-mediated tumor suppression and could be used as a general strategy to study the targets of individual miRNAs.

Sustained complete responses in patients with lymphoma receiving autologous cytotoxic T lymphocytes targeting Epstein-Barr virus latent membrane proteins

PURPOSE

Tumor cells from approximately 40% of patients with Hodgkin or non-Hodgkin lymphoma express the type II latency Epstein-Barr virus (EBV) antigens latent membrane protein 1 (LMP1) and LMP2, which represent attractive targets for immunotherapy. Because T cells specific for these antigens are present with low frequency and may be rendered anergic by the tumors that express them, we expanded LMP-cytotoxic T lymphocytes (CTLs) from patients with lymphoma using autologous dendritic cells and EBV-transformed B-lymphoblastoid cell lines transduced with an adenoviral vector expressing either LMP2 alone (n = 17) or both LMP2 and ΔLMP1 (n = 33).

PATIENTS AND METHODS

These genetically modified antigen-presenting cells expanded CTLs that were enriched for specificity against type II latency LMP antigens. When infused into 50 patients with EBV-associated lymphoma, the expanded CTLs did not produce infusional toxicities.

RESULTS

Twenty-eight of 29 high-risk or multiple-relapse patients receiving LMP-CTLs as adjuvant therapy remained in remission at a median of 3.1 years after CTL infusion. None subsequently died as a result of lymphoma, but nine succumbed to complications associated with extensive prior chemoradiotherapy, including myocardial infarction and secondary malignancies. Of 21 patients with relapsed or resistant disease at the time of CTL infusion, 13 had clinical responses, including 11 complete responses. T cells specific for LMP as well as nonviral tumor-associated antigens (epitope spreading) could be detected in the peripheral blood within 2 months after CTL infusion, but this evidence for epitope spreading was seen only in patients achieving clinical responses.

CONCLUSION

Autologous T cells directed to the LMP2 or LMP1 and LMP2 antigens can induce durable complete responses without significant toxicity. Their earlier use in the disease course may reduce delayed treatment-related mortality.

Epigenetic alterations in osteosarcoma: promising targets

Cancer is being reinterpreted due to recent discoveries related to epigenetic regulation during development, and the importance of epigenetic mechanisms in initiation and progression of cancer has been further highlighted by the recent explosion in medical information. Osteosarcoma is highly genetically unstable, and current therapeutic regimens are subject to chemoresistance and tumor relapse. Understanding the epigenetic mechanisms in the pathogenesis of osteosarcoma will provide novel avenues for cancer therapy. In this review, we examine the epigenetic alterations in gene expression in osteosarcoma, and discuss the utilization of epigenetic regulation therapy in treatment against osteosarcoma.

Customized targeted therapy in Hodgkin lymphoma: hype or hope?

Although most patients with Hodgkin lymphoma (HL) are cured with primary therapy, patients with primary refractory disease or relapse after initial treatment have poor outcomes and represent an unmet medical need. Recent advances in unraveling the biology of HL have yielded a plethora of novel targeted therapies. This review provides an overview of the data behind the hype generated by these advances and addresses the question of whether or not clinically these targeted therapies offer hope for patients with HL.

Genetically modified T-cell therapy for osteosarcoma

T-cell immunotherapy may offer an approach to improve outcomes for patients with osteosarcoma, who fail current therapies. In addition, it has the potential to reduce treatment-related complications for all patients. Generating tumor-specific T cells with conventional antigen presenting cells ex vivo is time consuming and often results in T-cell products with a low frequency of tumor-specific T cells. In addition, the generated T cells remain sensitive to the immunosuppressive tumor microenvironment. Genetic modification of T cells is one strategy to overcome these limitations. For example, T cells can be genetically modified to render them antigen specific, resistant to inhibitory factors, or increase their ability to home to tumor sites. Most genetic modification strategies have only been evaluated in preclinical models, however early phase clinical trials are in progress. In this chapter we review the current status of gene-modified T-cell therapy with special focus on osteosarcoma, highlighting potential antigenic targets, preclinical and clinical studies, and strategies to improve current T-cell therapy approaches.

Centrosomal localisation of the cancer/testis (CT) antigens NY-ESO-1 and MAGE-C1 is regulated by proteasome activity in tumour cells

The Cancer/Testis (CT) antigen family of genes are transcriptionally repressed in most human tissues but are atypically re-expressed in many malignant tumour types. Their restricted expression profile makes CT antigens ideal targets for cancer immunotherapy. As little is known about whether CT antigens may be regulated by post-translational processing, we investigated the mechanisms governing degradation of NY-ESO-1 and MAGE-C1 in selected cancer cell lines. Inhibitors of proteasome-mediated degradation induced the partitioning of NY-ESO-1 and MAGE-C1 into a detergent insoluble fraction. Moreover, this treatment also resulted in increased localisation of NY-ESO-1 and MAGE-C1 at the centrosome. Despite their interaction, relocation of either NY-ESO-1 or MAGE-C1 to the centrosome could occur independently of each other. Using a series of truncated fragments, the regions corresponding to NY-ESO-1_91-150 and MAGE-C1_900-1116 were established as important for controlling both stability and localisation of these CT antigens. Our findings demonstrate that the steady state levels of NY-ESO-1 and MAGE-C1 are regulated by proteasomal degradation and that both behave as aggregation-prone proteins upon accumulation. With proteasome inhibitors being increasingly used as front-line treatment in cancer, these data raise issues about CT antigen processing for antigenic presentation and therefore immunogenicity in cancer patients.

Genetically modified T cells for the treatment of malignant disease

The broaden application of adoptive T-cell transfer has been constrained by the technical abilities to isolate and expand antigen-specific T cells potent to selectively kill tumor cells. With the recent progress in the design and manufacturing of cellular products, T cells used in the treatment of malignant diseases may be regarded as anticancer biopharmaceuticals. Genetical manipulation of T cells has given T cells desired specificity but also enable to tailor their activation and proliferation potential. Here, we summarize the recent developments in genetic engineering of T-cell-based biopharmaceuticals, covering criteria for their clinical application in regard to safety and efficacy.