Next generations of CAR-T cells - new therapeutic opportunities in hematology?

Emerging advances in nano-biomaterial assisted amyloid beta chimeric antigen receptor macrophages (CAR-M) therapy: reducing plaque burden in Alzheimer's disease

Alzheimer's disease is the most common form, accounting for 60-70% of 55 million dementia cases. Even though the precise pathophysiology of AD is not completely understood, clinical trials focused on antibodies targeting aggregated forms of β amyloid (Aβ) have demonstrated that reducing amyloid plaques can arrest cognitive decline in patients in the early stages of AD. In this study, we provide an overview of current research and innovations for controlled release from nano-biomaterial-assisted chimeric antigen receptor macrophage (CAR-M) therapeutic strategies targeted at AD. Nano-bio materials, such as iron-oxide nanoparticles (IONPs), can be made selectively (Hp-Hb/mannose) to bind and take up Aβ plaques like CAR-M cells. By using nano-bio materials, both the delivery and stability of CAR-M cells in brain tissue can be improved to overcome the barriers of the BBB and enhance therapeutic effects. By enhancing the targeting capabilities and stability of CAR-M cells, mRNA-loaded nano-biomaterials can significantly improve the efficacy of immunotherapy for plaque reduction in AD. This novel strategy holds promise for translating preclinical successes into clinical applications, potentially revolutionising the management of AD.

Targeting refractory diffuse large B cell lymphoma by CAR-WEE1 T-cells: In vitro evaluation

Refractory Diffuse Large B-cell Lymphoma (DLBCL) presents a major therapeutic challenge due to its resistance to standard treatments. Engineered T-cells, especially Chimeric Antigen Receptor (CAR) T-cells, have shown promise in overcoming drug resistance. This study investigates the effectiveness of WEE1-engineered T-cells in targeting and eliminating refractory DLBCL in vitro. CAR T-cells were created by transducing a 5th-generation CAR construct designed to recognize WEE1, a surface antigen commonly found on refractory DLBCL cells. The cytotoxic effect of engineered T-cells was tested against Rituximab-resistant DLBCL cells (RR-NU-DUL-1). Apoptosis and cell cycle were evaluated using flow cytometry. Quantitative Real-time PCR (RT-PCR) was used to measure the expression of WEE1, BCL2, and CDK2. The results showed a significant increase in target cell lysis, apoptosis, and necrosis, a significant reduction in the percentage of cells in the G2M phase of the cell cycle, as well as a decrease in gene expression level, indicating strong anti-tumor activity. These findings suggest that CAR T-cell therapy holds great promise for treating refractory DLBCL, offering a potential path for clinical application. This in vitro evaluation highlights the potential of WEE1-engineered T-cells as a targeted treatment strategy for refractory DLBCL, emphasizing their clinical applicability and ability to overcome resistance mechanisms in this aggressive lymphoma subtype.

Enhancement of anti-sarcoma immunity by NK cells engineered with mRNA for expression of a EphA2-targeted CAR

BACKGROUND

Paediatric sarcomas, including rhabdomyosarcoma, Ewing sarcoma and osteosarcoma, represent a group of malignancies that significantly contribute to cancer-related morbidity and mortality in children and young adults. These cancers share common challenges, including high rates of metastasis, recurrence or treatment resistance, leading to a 5-year survival rate of approximately 20% for patients with advanced disease stages. Despite the critical need, therapeutic advancements have been limited over the past three decades. The advent of chimeric antigen receptor (CAR)-based immunotherapies offers a promising avenue for novel treatments. However, CAR-T cells have faced significant challenges and limited success in treating solid tumours due to issues such as poor tumour infiltration, immunosuppressive tumour microenvironments and off-target effects. In contrast, the adaptation of CAR technology for natural killer (NK) cells has demonstrated potential in both haematological and solid tumours, suggesting a new therapeutic strategy for paediatric sarcomas.

METHODS

This study developed and validated a novel CAR-NK cell therapy targeting the ephrin type-A receptor-2 (EphA2) antigen, which is highly expressed in various paediatric sarcomas.

RESULTS

CAR expression was successfully detected on the surface of NK cells post-electroporation, indicating successful transfection. Significantly, EphA2-specific CAR-NK cells demonstrated enhanced cytotoxic activity against several paediatric sarcoma cell lines in vitro, including those of rhabdomyosarcoma, Ewing sarcoma and osteosarcoma, compared to unmodified NK cells. Transient messenger RNA (mRNA) transfection of NK cells is a safe approach in genetic engineering, with further chemical modifications to mRNA enhancing stability of temporal EphA2-CAR expression in NK cells, thereby promoting prolonged protein expression. Additionally, in vivo EphA2-CAR-NK cells showed promising anti-cancer activity in rhabdomyosarcoma and osteosarcoma mouse models.

CONCLUSIONS

The study provides a foundational basis for the clinical evaluation of EphA2-targeted CAR-NK cell therapy across a spectrum of paediatric sarcomas. The enhanced anti-tumour effects observed in vitro/vivo suggests potential for improved therapeutic outcomes in hard-to-cure paediatric sarcomas.

KEY POINTS

Addressing unmet clinical needs in paediatric Sarcomas. Paediatric sarcomas, including rhabdomyosarcoma, Ewing sarcoma, and osteosarcoma, exhibit poor survival rates in advanced disease stages. The lack of significant therapeutic progress over the past three decades necessitates innovative treatment approaches. Advancing immunotherapy with CAR-NK cells. Natural killer (NK) cells modified with chimeric antigen receptors (CARs) represent a promising strategy to overcome the limitations of CAR-T cells, particularly in solid tumours. CAR-NK cells are associated with enhanced tumour targeting, reduced off-target effects, and improved safety profiles. EphA2 as a therapeutic target. EphA2, a receptor overexpressed in multiple paediatric sarcomas, is identified as a viable target for CAR-based immunotherapy due to its critical role in tumour progression and angiogenesis. Innovations in mRNA-based engineering. This study demonstrates the feasibility of transient mRNA transfection to engineer NK cells for CAR expression, offering a non-integrative and safer alternative to viral transduction. Enhancements in mRNA stability through chemical modifications, can further optimise protein expression. Preclinical efficacy of EphA2-CAR NK cells. EphA2-specific CAR-NK cells exhibit superior cytotoxicity against sarcoma cell lines in vitro and demonstrate significant anti-tumour activity in in vivo mouse models of rhabdomyosarcoma and osteosarcoma. Clinical translation potential. The findings establish a strong preclinical rationale for the clinical evaluation of EphA2-targeted CAR-NK therapy as a novel immunotherapeutic option for paediatric sarcomas. Future research directions: Combining EphA2-CAR NK cells with immune checkpoint inhibitors or other immunomodulatory agents could further enhance therapeutic outcomes and durability. Advanced preclinical models mimicking human tumour microenvironments are needed to refine and optimise this therapeutic approach.

Targeting Cancer: Microenvironment and Immunotherapy Innovations

In 2024, the United States was projected to experience 2 million new cancer diagnoses and approximately 611,720 cancer-related deaths, reflecting a broader global trend in which cancer cases are anticipated to exceed 35 million by 2050. This increasing burden highlights ongoing challenges in cancer treatment despite significant advances that have reduced cancer mortality by 31% since 1991. Key obstacles include the disease's inherent heterogeneity and complexity, such as treatment resistance, cancer stem cells, and the multifaceted tumor microenvironment (TME). The TME-comprising various tumor and immune cells, blood vessels, and biochemical factors-plays a crucial role in tumor growth and resistance to therapies. Recent innovations in cancer treatment, particularly in the field of immuno-oncology, have leveraged insights into TME interactions. An emerging example is the FDA-approved therapy using tumor-infiltrating lymphocytes (TILs), demonstrating the potential of cell-based approaches in solid tumors. However, TIL therapy is just one of many strategies being explored. This review provides a comprehensive overview of the emerging field of immuno-oncology, focusing on how novel therapies targeting or harnessing components of the TME could enhance treatment efficacy and address persistent challenges in cancer care.

Harnessing the potential of CAR-T cell in lupus treatment: From theory to practice

Systemic Lupus Erythematosus (SLE) is a rare, heterogeneous, potentially life-threatening autoimmune disease. Presence of kidney or other major organ (brain, heart or lung) involvement are predictors of poor outcome and in a subset of patients resistant to 1st or 2nd line conventional treatment. The 10-year mortality remains around 10-15 %. Chimeric Antigen Receptors (CAR) are molecules that allow to redirect the engineered immune cells towards specific target antigens and to simultaneously boost their activation. Following breakthrough results observed in the treatment of hematological malignancies, conventional CAR T-cell therapy has recently been applied to refractory SLE patients. Compared to the use of monoclonal antibodies, anti-CD19 CAR T-cells allow to achieve deeper depletion of autoreactive B cells, notably at site of inflamed tissues and lymphoid organs (i.e. lymph node), to suppress interferon signature and to restore the immune tolerance with the reemergence of naïve B-cells with a new repertoire. All clinical data reported in SLE patients so far showed that autologous anti-CD19 CAR T-cell treatment allowed impressive short- and longer-term resolution of lupus nephritis and other severe disease-related manifestations, without major toxicities and only mild cytokine-release syndrome. These clinical effects persisted after B-cell reconstitution and were associated with normalization of double-stranded DNA antibodies and complement levels in drug-free patients until three years after the procedure. Overall, these pioneering experiences show unique clinical and immunological response to CAR T-cell therapy in SLE, and the need for extended follow-up to determine its long-term efficacy.

Are we there yet? CAR-T therapy in multiple myeloma

The last few years have seen a revolution in cellular immunotherapies for multiple myeloma (MM) with novel antigen targets. The principle new target is B-cell maturation antigen (BCMA). Autologous chimeric antigen receptor T-cell (CAR-T) therapy directed against BCMA was first approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) in 2021, although approval by the National Institute for Health and Care Excellent (NICE) is awaited. Initial response rates in patients with heavily pretreated MM have been impressive, but patients are still relapsing. Furthermore, CAR-T manufacturing is expensive and time-consuming, and T-cell fitness is impaired by prior MM treatment. Numerous strategies to improve outcomes and delivery of cellular immunotherapy are under investigation, including next-generation CARs, allogeneic 'off-the-shelf' CARs and targeting of other MM antigens including G protein-coupled receptor, class C, group 5, member D (GPRC5D), Fc receptor homologue 5 (FcRH5), cluster of differentiation (CD)19, signalling lymphocyte activation molecule family member 7 (SLAMF7) and several others. In this exciting and rapidly evolving treatment landscape, this review evaluates the most recent clinical and preclinical data pertaining to these new cellular immunotherapies and explores strategies to overcome resistance pathways. On the protracted journey to a long-term cure, we outline the challenges that lie ahead and ask, 'Are we there yet?'

Armoring chimeric antigen receptor (CAR) T cells as micropharmacies for cancer therapy

Chimeric antigen receptor (CAR)-T-cell therapy has emerged as a powerful weapon in the fight against cancer. However, its efficacy is often hindered by challenges such as limited tumor penetration, antigen escape, and immune suppression within the tumor microenvironment. This review explores the potential of armored CAR-T cells, or 'micropharmacies', in overcoming these obstacles and enhancing the therapeutic outcomes of adoptive T-cell (ATC) therapy. We delve into the engineering strategies behind these advanced therapies and the mechanisms through which they improve CAR-T-cell efficacy. Additionally, we discuss the latest advancements and research findings in the field, providing a comprehensive understanding of the role of armored CAR-T cells in cancer treatment. Ultimately, this review highlights the promising future of integrating micropharmacies into ATC therapy, paving the way for more effective and targeted cancer treatments.

Logic-gated and contextual control of immunotherapy for solid tumors: contrasting multi-specific T cell engagers and CAR-T cell therapies

CAR-T cell and T cell engager therapies have demonstrated transformational efficacy against hematological malignancies, but achieving efficacy in solid tumors has been more challenging, in large part because of on-target/off-tumor toxicities and sub-optimal T cell anti-tumor cytotoxic functions. Here, we discuss engineering solutions that exploit biological properties of solid tumors to overcome these challenges. Using logic gates as a framework, we categorize the numerous approaches that leverage two inputs instead of one to achieve better cancer selectivity or efficacy in solid tumors with dual-input CAR-Ts or multi-specific TCEs. In addition to the "OR gate" and "AND gate" approaches that leverage dual tumor antigen targeting, we also review "contextual AND gate" technologies whereby continuous cancer-selective inputs such a pH, hypoxia, target density, tumor proteases, and immune-suppressive cytokine gradients can be creatively incorporated in therapy designs. We also introduce the notion of "output directionality" to distinguish dual-input strategies that mechanistically impact cancer cell killing or T cell fitness. Finally, we contrast the feasibility and potential benefits of the various approaches using CAR-T and TCE therapeutics and discuss why the promising "IF/THEN" and "NOT" gate types pertain more specifically to CAR-T therapies, but can also succeed by integrating both technologies.

Focusing on exosomes to overcome the existing bottlenecks of CAR-T cell therapy

Since chimeric antigen receptor T (CAR-T) cells were introduced three decades ago, the treatment using these cells has led to outstanding outcomes, and at the moment, CAR-T cell therapy is a well-established mainstay for treating CD19 + malignancies and multiple myeloma. Despite the astonishing results of CAR-T cell therapy in B-cell-derived malignancies, several bottlenecks must be overcome to promote its safety and efficacy and broaden its applicability. These bottlenecks include cumbersome production process, safety concerns of viral vectors, poor efficacy in treating solid tumors, life-threatening side effects, and dysfunctionality of infused CAR-T cells over time. Exosomes are nano-sized vesicles that are secreted by all living cells and play an essential role in cellular crosstalk by bridging between cells. In this review, we discuss how the existing bottlenecks of CAR-T cell therapy can be overcome by focusing on exosomes. First, we delve into the effect of tumor-derived exosomes on the CAR-T cell function and discuss how inhibiting their secretion can enhance the efficacy of CAR-T cell therapy. Afterward, the application of exosomes to the manufacturing of CAR-T cells in a non-viral approach is discussed. We also review the latest advancements in ex vivo activation and cultivation of CAR-T cells using exosomes, as well as the potential of engineered exosomes to in vivo induction or boost the in vivo proliferation of CAR-T cells. Finally, we discuss how CAR-engineered exosomes can be used as a versatile tool for the direct killing of tumor cells or delivering intended therapeutic payloads in a targeted manner.

[The new generations of CAR-T cells]

Chimeric antigen receptor (CAR)-T is one of the most promising modern cancer immunotherapies. In the recent years, impressive results have been obtained in the treatment of cancer which led to FDA approval for the treatment of liquid tumors. In this cell-based therapy, immune cells (e.g. T and NK cells) are engineered to express a synthetic receptor CAR to specifically recognize and eliminate cells expressing a target antigen. CAR has evolved through different generations aiming to boost its biological activity and overcome limitations such as low persistence, limited potency, life-threatening toxicity and inefficient activity against solid tumor. The present review provides an overview of the different CAR generations, starting from the 1st generation with limited cytotoxic activity until the latest generation, the 5th generation or new generation, developed to overcome various limitations of CAR T therapy. The current ongoing clinical trials in cancer and autoimmune diseases, and the limitation associated with CAR-T cells in cancer therapy, are also discussed.

Next-Generation Immunotherapy: Advancing Clinical Applications in Cancer Treatment

Next-generation immunotherapies have revolutionized cancer treatment, offering hope for patients with hard-to-treat tumors. This review focuses on the clinical applications and advancements of key immune-based therapies, including immune checkpoint inhibitors, CAR-T cell therapy, and new cancer vaccines designed to harness the immune system to combat malignancies. A prime example is the success of pembrolizumab in the treatment of advanced melanoma, underscoring the transformative impact of these therapies. Combination treatments, integrating immunotherapy with chemotherapy, radiation, and targeted therapies, are demonstrating synergistic benefits and improving patient outcomes. This review also explores the evolving role of personalized immunotherapy, guided by biomarkers, genomic data, and the tumor environment, to better target individual tumors. Although significant progress has been made, challenges such as resistance, side effects, and high treatment costs persist. Technological innovations, including nanotechnology and artificial intelligence, are explored as future enablers of these therapies. The review evaluates key clinical trials, breakthroughs, and the emerging immune-modulating agents and advanced delivery systems that hold great promise for enhancing treatment efficacy, reducing toxicity, and expanding access to immunotherapy. In conclusion, this review highlights the ongoing advancements in immunotherapy that are reshaping cancer care, with future strategies poised to overcome current challenges and further extend therapeutic reach.

Advancing Immunotherapy in Pancreatic Cancer

Pancreatic cancer remains one of the deadliest malignancies, with a consistently low five-year survival rate for the past several decades. This is in stark contrast to other cancers, which have seen significant improvement in survival and prognosis due to recent developments in therapeutic modalities. These modest improvements in pancreatic cancer outcomes have primarily resulted from minor advances in cytotoxic chemotherapeutics, with limited progress in other treatment approaches. A major focus of current therapeutic research is the further development of immunomodulatory therapies characterized by antibody-based approaches, cellular therapies, and vaccines. Although initial results utilizing immunotherapy in pancreatic cancer have been mixed, recent clinical trials have demonstrated significant improvements in patient outcomes. In this review, we detail these three approaches to immunomodulation, highlighting their common targets and distinct shortcomings, and we provide a narrative summary of completed and ongoing clinical trials that utilize these approaches to immunomodulation. Within this context, we aim to inform future research efforts by identifying promising areas that warrant further exploration.

Tumor Biology Hides Novel Therapeutic Approaches to Diffuse Large B-Cell Lymphoma: A Narrative Review

Diffuse large B-cell lymphoma (DLBCL) is a malignancy of immense biological and clinical heterogeneity. Based on the transcriptomic or genomic approach, several different classification schemes have evolved over the years to subdivide DLBCL into clinically (prognostically) relevant subsets, but each leaves unclassified samples. Herein, we outline the DLBCL tumor biology behind the actual and potential drug targets and address the challenges and drawbacks coupled with their (potential) use. Therapeutic modalities are discussed, including small-molecule inhibitors, naked antibodies, antibody-drug conjugates, chimeric antigen receptors, bispecific antibodies and T-cell engagers, and immune checkpoint inhibitors. Candidate drugs explored in ongoing clinical trials are coupled with diverse toxicity issues and refractoriness to drugs. According to the literature on DLBCL, the promise for new therapeutic targets lies in epigenetic alterations, B-cell receptor and NF-κB pathways. Herein, we present putative targets hiding in lipid pathways, ferroptosis, and the gut microbiome that could be used in addition to immuno-chemotherapy to improve the general health status of DLBCL patients, thus increasing the chance of being cured. It may be time to devote more effort to exploring DLBCL metabolism to discover novel druggable targets. We also performed a bibliometric and knowledge-map analysis of the literature on DLBCL published from 2014-2023.

Advancements in tumor-infiltrating lymphocytes: Historical insights, contemporary milestones, and future directions in oncology therapy

Tumor-infiltrating lymphocytes (TILs) are a subtype of immune cells that infiltrate and accumulate within tumors. Studies proved that TILs can be used as prognostic and predictive markers for cancer patients' responses to immunotherapy. This review explores the modern knowledge of TILs, the challenges and opportunities for utilizing TILs in cancer treatment, such as the rise of therapies under TIL circumstances, the identification of biomarkers for TIL activity, and methods used to isolate and expand TILs for therapeutic use. Ongoing clinical trials and promising results in different cancer types are highlighted, including melanoma, ovarian, and colorectal cancer. This also focuses on ongoing efforts to improve TIL-based therapies by identifying the specific subsets of TILs that are most effective in treating cancer and developing methods to increase the functionality and persistence of TILs in the tumor microenvironment. The article recapitulates the present state TILs therapy, ongoing research, and improvements to its potency.

Antigen escape in CAR-T cell therapy: Mechanisms and overcoming strategies

Chimeric antigen receptor T (CAR-T) cell therapy has shown promise in treating hematological malignancies and certain solid tumors. However, its efficacy is often hindered by negative relapses resulting from antigen escape. This review firstly elucidates the mechanisms underlying antigen escape during CAR-T cell therapy, including the enrichment of pre-existing target-negative tumor clones, antigen gene mutations or alternative splicing, deficits in antigen processing, antigen redistribution, lineage switch, epitope masking, and trogocytosis-mediated antigen loss. Furthermore, we summarize various strategies to overcome antigen escape, evaluate their advantages and limitations, and propose future research directions. Thus, we aim to provide valuable insights to enhance the effectiveness of CAR-T cell therapy.

Exploring the potential of the convergence between extracellular vesicles and CAR technology as a novel immunotherapy approach

Cancer therapy is a dynamically evolving field, witnessing the emergence of innovative approaches that offer a promising outlook for patients grappling with persistent disease. Within the realm of therapeutic exploration, chimeric antigen receptor (CAR) T cells as well as CAR NK cells, have surfaced as novel approaches, each possessing unique attributes and transformative potential. Immune cells engineered to express CARs recognizing tumour-specific antigens, have shown remarkable promise in treating terminal cancers by combining the precision of antibody specificity with the potent cytotoxic function of T cells. However, their application in solid tumours is still in its nascent stages, presenting unique major challenges. On the same note, CAR NK cells offer a distinct immunotherapeutic approach, utilizing CARs on NK cells, providing advantages in safety, manufacturing simplicity, and a broader scope for cancer treatment. Extracellular vesicles (EVs) have emerged as promising therapeutic agents due to their ability to carry crucial biomarkers and biologically active molecules, serving as vital messengers in the intercellular communication network. In the context of cancer, the therapeutic potential of EVs lies in delivering tumour-suppressing proteins, nucleic acid components, or targeting drugs with precision, thereby redefining the paradigm of precision medicine. The fusion of CAR technology with the capabilities of EVs has given rise to a new therapeutic frontier. CAR T EVs and CAR NK EVs, leveraging the power of EVs, have the potential to alleviate challenges associated with live-cell therapies. EVs are suggested to reduce the side effects linked to CAR T cell therapy and hold the potential to revolutionize the penetrance in solid tumours. EVs act as carriers of pro-apoptotic molecules and RNA components, enhancing immune responses and thereby expanding their therapeutic potential. In this review article, we navigate dynamic landscapes, with our objective being to evaluate comparative efficacy, safety profiles, manufacturing complexities, and clinical applicability.

CAR-NK Cell Therapy: A Transformative Approach to Overcoming Oncological Challenges

The use of chimeric antigen receptor (CAR) in natural killer (NK) cells for cancer therapy is gaining momentum, marking a significant shift in cancer treatment. This review aims to explore the potential of CAR-NK cell therapy in cancer immunotherapy, providing a fresh perspective. It discusses the innovative approaches in CAR-NK cell design and engineering, particularly targeting refractory or recurrent cancers. By comparing CAR-NK cells with traditional therapies, the review highlights their unique ability to tackle tumor heterogeneity and immune system suppression. Additionally, it explains how novel cytokines and receptors can enhance CAR-NK cell efficacy, specificity, and functionality. This review underscores the advantages of CAR-NK cells, including reduced toxicity, lower cost, and broader accessibility compared to CAR-T cells, along with their potential in treating both blood cancers and solid tumors.

Different Strategies to Overcome Resistance to Proteasome Inhibitors-A Summary 20 Years after Their Introduction

Proteasome inhibitors (PIs), bortezomib, carfilzomib, and ixazomib, are the first-line treatment for multiple myeloma (MM). They inhibit cytosolic protein degradation in cells, which leads to the accumulation of misfolded and malfunctioned proteins in the cytosol and endoplasmic reticulum, resulting in cell death. Despite being a breakthrough in MM therapy, malignant cells develop resistance to PIs via different mechanisms. Understanding these mechanisms drives research toward new anticancer agents to overcome PI resistance. In this review, we summarize the mechanism of action of PIs and how MM cells adapt to these drugs to develop resistance. Finally, we explore these mechanisms to present strategies to interfere with PI resistance. The strategies include new inhibitors of the ubiquitin-proteasome system, drug efflux inhibitors, autophagy disruption, targeting stress response mechanisms, affecting survival and cell cycle regulators, bone marrow microenvironment modulation, and immunotherapy. We list potential pharmacological targets examined in in vitro, in vivo, and clinical studies. Some of these strategies have already provided clinicians with new anti-MM medications, such as panobinostat and selinexor. We hope that further exploration of the subject will broaden the range of therapeutic options and improve patient outcomes.

Strategies to overcome tumor microenvironment immunosuppressive effect on the functioning of CAR-T cells in high-grade glioma

Despite significant progress in the treatment of some types of cancer, high-grade gliomas (HGGs) remain a significant clinical problem. In the case of glioblastoma (GBM), the most common solid tumor of the central nervous system in adults, the average survival time from diagnosis is only 15-18 months, despite the use of intensive multimodal therapy. Chimeric antigen receptor (CAR)-expressing T cells, which have already been approved by the Food and Drug Administration for use in the treatment of certain hematologic malignancies, are a new, promising therapeutic option. However, the efficacy of CAR-T cells in solid tumors is lower due to the immunosuppressive tumor microenvironment (TME). Reprogramming the immunosuppressive TME toward a pro-inflammatory phenotype therefore seems particularly important because it may allow for increasing the effectiveness of CAR-T cells in the therapy of solid tumors. The following literature review aims to present the results of preclinical studies showing the possibilities of improving the efficacy of CAR-T in the TME of GBM by reprogramming the TME toward a pro-inflammatory phenotype. It may be achievable thanks to the use of CAR-T in a synergistic therapy in combination with oncolytic viruses, radiotherapy, or epigenetic inhibitors, as well as by supporting CAR-T cells crossing of the blood-brain barrier, normalizing impaired angiogenesis in the TME, improving CAR-T effector functions by cytokine signaling or by blocking/knocking out T-cell inhibitors, and modulating the microRNA expression. The use of CAR-T cells modified in this way in synergistic therapy could lead to the longer survival of patients with HGG by inducing an endogenous anti-tumor response.

Chimeric antigen receptor dendritic cells targeted delivery of a single tumoricidal factor for cancer immunotherapy

BACKGROUND

Chimeric antigen receptor (CAR)-T cells have been used to treat blood cancers by producing a wide variety of cytokines. However, they are not effective in treating solid cancers and can cause severe side-effects, including cytokine release syndrome. TNFα is a tumoricidal cytokine, but it markedly increases the protein levels of cIAP1 and cIAP2, the members of inhibitor of apoptosis protein (IAP) family of E3 ubiquitin ligase that limits caspase-induced apoptosis. Degradation of IAP proteins by an IAP antagonist does not effectively kill cancer cells but enables TNFα to strongly induce cancer cell apoptosis. It would be a promising approach to treat cancers by targeted delivery of TNFα through an inactive adoptive cell in combination with an IAP antagonist.

METHODS

Human dendritic cells (DCs) were engineered to express a single tumoricidal factor, TNFα, and a membrane-anchored Mucin1 antibody scFv, named Mucin 1 directed DCs expressing TNFα (M-DCsTNF). The efficacy of M-DCsTNF in recognizing and treating breast cancer was tested in vitro and in vivo.

RESULTS

Mucin1 was highly expressed on the surface of a wide range of human breast cancer cell lines. M-DCsTNF directly associated with MDA-MB-231 cells in the bone of NSG mice. M-DCsTNF plus an IAP antagonist, SM-164, but neither alone, markedly induce MDA-MB-231 breast cancer cell apoptosis, which was blocked by TNF antibody. Importantly, M-DCsTNF combined with SM-164, but not SM-164 alone, inhibited the growth of patient-derived breast cancer in NSG mice.

CONCLUSION

An adoptive cell targeting delivery of TNFα combined with an IAP antagonist is a novel effective approach to treat breast cancer and could be expanded to treat other solid cancers. Unlike CAR-T cell, this novel adoptive cell is not activated to produce a wide variety of cytokines, except for additional overexpressed TNF, and thus could avoid the severe side effects such as cytokine release syndrome.

Advanced strategies in improving the immunotherapeutic effect of CAR-T cell therapy

Chimeric antigen receptor (CAR-T) cell therapy is a newly developed immunotherapy strategy and has achieved satisfactory outcomes in the treatment of hematological malignancies. However, some adverse effects related to CAR-T cell therapy have to be resolved before it is widely used in clinics as a cancer treatment. Furthermore, the application of CAR-T cell therapy in the treatment of solid tumors has been hampered by numerous limitations. Therefore, it is essential to explore novel strategies to improve the therapeutic effect of CAR-T cell therapy. In this review, we summarized the recently developed strategies aimed at optimizing the generation of CAR-T cells and improving the anti-tumor efficiency of CAR-T cell therapy. Furthermore, the discovery of new targets for CAR-T cell therapy and the combined treatment strategies of CAR-T cell therapy with chemotherapy, radiotherapy, cancer vaccines and nanomaterials are highlighted.

Advancing autoimmune Rheumatic disease treatment: CAR-T Cell Therapies - Evidence, Safety, and future directions

INTRODUCTION

Despite advancements in managing autoimmune rheumatic diseases (ARDs) with existing treatments, many patients still encounter challenges such as inadequate responses, difficulty in maintaining remission, and side effects. Chimeric Antigen Receptor (CAR) T-cell therapy, originally developed for cancer, has now emerged as a promising option for cases of refractory ARDs.

METHODS

A search of the literature was conducted to compose a narrative review exploring the current evidence, potential safety, limitations, potential modifications, and future directions of CAR-T cells in ARDs.

RESULTS

CAR-T cell therapy has been administered to patients with refractory ARDs, including systemic lupus erythematosus, antisynthetase syndrome, and systemic sclerosis, demonstrating significant improvement. Notable responses include enhanced clinical symptoms, reduced serum autoantibody titers, and sustained remissions in disease activity. Preclinical and in vitro studies using both animal and human samples also support the efficacy and elaborate on potential mechanisms of CAR-T cells against antineutrophil cytoplasmic antibody-associated vasculitis and rheumatoid arthritis. While cautious monitoring of adverse events, such as cytokine release syndrome, is crucial, the therapy appears to be highly tolerable. Nevertheless, challenges persist, including cost, durability due to potential CAR-T cell exhaustion, and manufacturing complexities, urging the development of innovative solutions to further enhance CAR-T cell therapy accessibility in ARDs.

CONCLUSIONS

CAR-T cell therapy for refractory ARDs has demonstrated high effectiveness. While no significant warning signs are currently reported, achieving a balance between therapeutic efficacy and safety is vital in adapting CAR-T cell therapy for ARDs. Moreover, there is significant potential for technological advancements to enhance the delivery of this treatment to patients, thereby ensuring safer and more effective disease control for patients.

CRISPR-Cas gene knockouts to optimize engineered T cells for cancer immunotherapy

While CAR-T and tgTCR-T therapies have exhibited noteworthy and promising outcomes in hematologic and solid tumors respectively, a set of distinct challenges remains. Consequently, the quest for novel strategies has become imperative to safeguard and more effectively release the full functions of engineered T cells. These factors are intricately linked to the success of adoptive cell therapy. Recently, CRISPR-based technologies have emerged as a major breakthrough for maintaining T cell functions. These technologies have allowed the discovery of T cells' negative regulators such as specific cell-surface receptors, cell-signaling proteins, and transcription factors that are involved in the development or maintenance of T cell dysfunction. By employing a CRISPR-genic invalidation approach to target these negative regulators, it has become possible to prevent the emergence of hypofunctional T cells. This review revisits the establishment of the dysfunctional profile of T cells before delving into a comprehensive summary of recent CRISPR-gene invalidations, with each invalidation contributing to the enhancement of engineered T cells' antitumor capacities. The narrative unfolds as we explore how these advancements were discovered and identified, marking a significant advancement in the pursuit of superior adoptive cell therapy.

Advancements in Personalized CAR-T Therapy: Comprehensive Overview of Biomarkers and Therapeutic Targets in Hematological Malignancies

Chimeric antigen receptor T-cell (CAR-T) therapy is a novel anticancer therapy using autologous or allogeneic T-cells. To date, six CAR-T therapies for specific B-cell acute lymphoblastic leukemia (B-ALL), non-Hodgkin lymphomas (NHL), and multiple myeloma (MM) have been approved by the Food and Drug Administration (FDA). Significant barriers to the effectiveness of CAR-T therapy include cytokine release syndrome (CRS), neurotoxicity in the case of Allogeneic Stem Cell Transplantation (Allo-SCT) graft-versus-host-disease (GVHD), antigen escape, modest antitumor activity, restricted trafficking, limited persistence, the immunosuppressive microenvironment, and senescence and exhaustion of CAR-Ts. Furthermore, cancer drug resistance remains a major problem in clinical practice. CAR-T therapy, in combination with checkpoint blockades and bispecific T-cell engagers (BiTEs) or other drugs, appears to be an appealing anticancer strategy. Many of these agents have shown impressive results, combining efficacy with tolerability. Biomarkers like extracellular vesicles (EVs), cell-free DNA (cfDNA), circulating tumor (ctDNA) and miRNAs may play an important role in toxicity, relapse assessment, and efficacy prediction, and can be implicated in clinical applications of CAR-T therapy and in establishing safe and efficacious personalized medicine. However, further research is required to fully comprehend the particular side effects of immunomodulation, to ascertain the best order and combination of this medication with conventional chemotherapy and targeted therapies, and to find reliable predictive biomarkers.

Optimizing the Design and Geometry of T Cell-Engaging Bispecific Antibodies Targeting CEA in Colorectal Cancer

Metastatic colorectal cancer remains a leading cause of cancer-related deaths, with a 5-year survival rate of only 15%. T cell-engaging bispecific antibodies (TCBs) represent a class of biopharmaceuticals that redirect cytotoxic T cells toward tumor cells, thereby turning immunologically "cold" tumors into "hot" ones. The carcinoembryonic antigen (CEA) is an attractive tumor-associated antigen that is overexpressed in more than 98% of patients with colorectal cancer. In this study, we report the comparison of four different TCB formats employing the antibodies F4 (targeting human CEA) and 2C11 (targeting mouse CD3ε). These formats include both antibody fragment-based and IgG-based constructs, with either one or two binding specificities of the respective antibodies. The 2 + 1 arrangement, using an anti-CEA single-chain diabody fused to an anti-CD3 single-chain variable fragment, emerged as the most potent design, showing tumor killing at subnanomolar concentrations across three different CEA+ cell lines. The in vitro activity was three times greater in C57BL/6 mouse colon adenocarcinoma cells (MC38) expressing high levels of CEA compared with those expressing low levels, highlighting the impact of CEA density in this assay. The optimal TCB candidate was tested in two different immunocompetent mouse models of colorectal cancer and showed tumor growth retardation. Ex vivo analysis of tumor infiltrates showed an increase in CD4+ and CD8+ T cells upon TCB treatment. This study suggests that bivalent tumor targeting, monovalent T-cell targeting, and a short spatial separation are promising characteristics for CEA-targeting TCBs.

Accelerating the development of genetically engineered cellular therapies: a framework for extrapolating data across related products

BACKGROUND

Significant advancements have been made in the field of cellular therapy as anti-cancer treatments, with the approval of chimeric antigen receptor (CAR)-T cell therapies and the development of other genetically engineered cellular therapies. CAR-T cell therapies have demonstrated remarkable clinical outcomes in various hematological malignancies, establishing their potential to change the current cancer treatment paradigm. Due to the increasing importance of genetically engineered cellular therapies in the oncology treatment landscape, implementing strategies to expedite development and evidence generation for the next generation of cellular therapy products can have a positive impact on patients.

METHODS

We outline a risk-based methodology and assessment aid for the data extrapolation approach across related genetically engineered cellular therapy products. This systematic data extrapolation approach has applicability beyond CAR-T cells and can influence clinical development strategies for a variety of immune therapies such as T cell receptor (TCR) or genetically engineered and other cell-based therapies (e.g., tumor infiltrating lymphocytes, natural killer cells and macrophages).

RESULTS

By analyzing commonalities in manufacturing processes, clinical trial designs, and regulatory considerations, key learnings were identified. These insights support optimization of the development and regulatory approval of novel cellular therapies.

CONCLUSIONS

The field of cellular therapy holds immense promise in safely and effectively treating cancer. The ability to extrapolate data across related products presents opportunities to streamline the development process and accelerate the delivery of novel therapies to patients.

CAR T therapy from haematological malignancies to aging-related diseases: An ever-expanding universe

BACKGROUND

Short but impactful, the two-decade story of gene editing allowed a significant breakthrough in the treatment of haematological malignancies. However, despite different generations of chimeric antigen receptor T (CAR T), such a successful therapy has not yet been replicated in solid tumours and non-oncological diseases.

METHODS

This narrative review discusses how CAR T therapy still faces challenges in overcoming the complexity of the solid tumour microenvironment and the concerns that its long-term activity raises about potential unknown and unpredictable consequences in non-oncological diseases.

RESULTS

In the most recent studies, the senolytic potential of CAR T is becoming an exciting field of research. Still, experimental but promising results indeed indicate the clearance of senescent cells as an effective strategy to improve exercise capacity and metabolic dysfunction in physiological ageing, with long-term therapeutic and preventive effects. However, an effective expansion of a CAR T population requires a lympho-depleting chemotherapy prior to infusion. While this procedure sounds reasonable for rescue therapy of oncological diseases, it poses genotoxic risks that may not be justified for non-malignant diseases. Those represent the leading gaps for applying CAR T therapy in non-oncological diseases.

CONCLUSION

More is expected from current studies on the other classes of CAR cells now under investigation. Engineering NK cells and macrophages are candidates to improve cytotoxic and immunomodulating properties, potentially able to broaden application in solid tumours and non-oncological diseases. Finally, engineering autologous T cells in old individuals may generate biologically deteriorated CAR T clones with impaired function and unpredictable effects on cytokine release.

Alternative target recognition elements for chimeric antigen receptor (CAR) T cells: beyond standard antibody fragments

BACKGROUND AIMS

Chimeric antigen receptor T (CAR-T) cells are a remarkably efficacious, highly promising and rapidly evolving strategy in the field of immuno-oncology. The precision of these targeted cellular therapies is driven by the specificity of the antigen recognition element (the "binder") encoded in the CAR. This binder redirects these immune effector cells precisely toward a defined antigen on the surface of cancer cells, leading to T-cell receptor-independent tumor lysis. Currently, for tumor targeting most CAR-T cells are designed using single-chain variable fragments (scFvs) derived from murine or human immunoglobulins. However, there are several emerging alternative binder modalities that are finding increasing utility for improved CAR function beyond scFvs.

METHODS

Here we review the most recent developments in the use of non-canonical protein binding domains in CAR design, including nanobodies, DARPins, natural ligands, and de novo-designed protein elements.

RESULTS

Overall, we describe how new protein binder formats, with their unique structural properties and mechanisms of action, may possess key advantages over traditional scFv CAR designs.

CONCLUSIONS

These alternative binder designs may contribute to enhanced CAR-T therapeutic options and, ultimately, improved outcomes for cancer patients.

Contemporary Approaches to Immunotherapy of Solid Tumors

In recent years, the arrival of the immunotherapy industry has introduced the possibility of providing transformative, durable, and potentially curative outcomes for various forms of malignancies. However, further research has shown that there are a number of issues that significantly reduce the effectiveness of immunotherapy, especially in solid tumors. First of all, these problems are related to the protective mechanisms of the tumor and its microenvironment. Currently, major efforts are focused on overcoming protective mechanisms by using different adoptive cell therapy variants and modifications of genetically engineered constructs. In addition, a complex workforce is required to develop and implement these treatments. To overcome these significant challenges, innovative strategies and approaches are necessary to engineer more powerful variations of immunotherapy with improved antitumor activity and decreased toxicity. In this review, we discuss recent innovations in immunotherapy aimed at improving clinical efficacy in solid tumors, as well as strategies to overcome the limitations of various immunotherapies.

Novel Targets and Advanced Therapies in Diffuse Large B Cell Lymphomas

Since the introduction of rituximab in the late 1990s, significant progress has been made in advancing targeted therapies for B cell lymphomas, improving patients' chance of being cured and clinicians' therapeutic armamentarium. A better understanding of disease biology and pathogenic pathways, coupled with refinements in immunophenotypic and molecular diagnostics, have been instrumental in these achievements. While traditional chemotherapy remains fundamental in most cases, concerns surrounding chemorefractoriness and cumulative toxicities, particularly the depletion of the hemopoietic reserve, underscore the imperative for personalized treatment approaches. Integrating targeted agents, notably monoclonal antibodies, alongside chemotherapy has yielded heightened response rates and prolonged survival. A notable paradigm shift is underway with innovative-targeted therapies replacing cytotoxic drugs, challenging conventional salvage strategies like stem cell transplantation. This review examines the landscape of emerging targets for lymphoma cells and explores innovative therapies for diffuse large B cell lymphoma (DLBCL). From Chimeric Antigen Receptor-T cells to more potent monoclonal antibodies, antibody-drug conjugates, bispecific antibodies, checkpoint inhibitors, and small molecules targeting intracellular pathways, each modality offers promising avenues for therapeutic advancement. This review aims to furnish insights into their potential implications for the future of DLBCL treatment strategies.

Current and future immunotherapeutic approaches in pancreatic cancer treatment

Pancreatic cancer is a major cause of cancer-related death, but despondently, the outlook and prognosis for this resistant type of tumor have remained grim for a long time. Currently, it is extremely challenging to prevent or detect it early enough for effective treatment because patients rarely exhibit symptoms and there are no reliable indicators for detection. Most patients have advanced or spreading cancer that is difficult to treat, and treatments like chemotherapy and radiotherapy can only slightly prolong their life by a few months. Immunotherapy has revolutionized the treatment of pancreatic cancer, yet its effectiveness is limited by the tumor's immunosuppressive and hard-to-reach microenvironment. First, this article explains the immunosuppressive microenvironment of pancreatic cancer and highlights a wide range of immunotherapy options, including therapies involving oncolytic viruses, modified T cells (T-cell receptor [TCR]-engineered and chimeric antigen receptor [CAR] T-cell therapy), CAR natural killer cell therapy, cytokine-induced killer cells, immune checkpoint inhibitors, immunomodulators, cancer vaccines, and strategies targeting myeloid cells in the context of contemporary knowledge and future trends. Lastly, it discusses the main challenges ahead of pancreatic cancer immunotherapy.

How I treat newly diagnosed acute lymphoblastic leukemia

Treatment algorithms differ for adult patients with Philadelphia-negative (Ph-) and Philadelphia-positive (Ph+) acute lymphoblastic leukemia (ALL). For Ph- ALL intensive induction-consolidation chemotherapy using "pediatric-inspired" protocols is a standard of care. Allogeneic hematopoietic cell transplantation (allo-HCT) from either an HLA-matched sibling, unrelated or haploidentical donor should be considered for patients with high estimated risk of relapse. Inadequate response at the level of measurable residual disease (MRD) is the strongest adverse prognostic factor. Patients with B-ALL and detectable MRD should be treated with blinatumomab. In the future, the use of blinatumomab and/or inotuzumab ozogamycin in addition to first-line chemotherapy may become a new standard of care reducing the role of allo-HCT. For patients with Ph+ ALL, tyrosine kinase inhibitors (TKI) are the most important components of treatment protocols, while the intensity of chemotherapy may be reduced. Allo-HCT is recommended for all patients treated with imatinib along with low-intensity chemotherapy. Results of phase-II studies using front-line dasatinib or ponatinib in sequence or in combination with blinatumomab are very promising. Such a strategy may allow the avoidance of systemic chemotherapy. The future role of allo-HCT in this context appears uncertain.

A new vision of the efficacy of both CAR-NK and CAR-T cells in treating cancers and autoimmune diseases

Chimeric Antigen Receptor (CAR) based therapies are becoming increasingly important in treating patients. CAR-T cells have been shown to be highly effective in the treatment of hematological malignancies. However, harmful therapeutic barriers have been identified, such as the potential for graft-versus-host disease (GVHD), neurotoxicity, and cytokine release syndrome (CRS). As a result, CAR NK-cell therapy is expected to be a new therapeutic option. NK cells act as cytotoxic lymphocytes, supporting the innate immune response against autoimmune diseases and cancer cells by precisely detecting and eliminating malignant cells. Genetic modification of these cells provides a dual approach to the treatment of AD and cancer. It can be used through both CAR-independent and CAR-dependent mechanisms. The use of CAR-based cell therapies has been successful in treating cancer patients, leading to further investigation of this innovative treatment for alternative diseases, including AD. The complementary roles of CAR T and CAR NK cells have stimulated exploration in this area. Our study examines the latest research on the therapeutic effectiveness of these cells in treating both cancer and ADs.

Chimeric antigen receptor (CAR) modified T Cells in acute myeloid leukemia: limitations and expectations

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy with a poor prognosis despite the advent of novel therapies. Consequently, a major need exists for new therapeutic options, particularly for patients with relapsed/refractory (R/R) AML. In recent years, it has been possible to individualize the treatment of a subgroup of patients, particularly with the emergence of multiple targeted therapies. Nonetheless, a considerable number of patients remain without therapeutic options, and overall prognosis remains poor because of a high rate of disease relapse. In this sense, cellular therapies, especially chimeric antigen receptor (CAR)-T cell therapy, have dramatically shifted the therapeutic options for other hematologic malignancies, such as diffuse large B cell lymphoma and acute lymphoblastic leukemia. In contrast, effectively treating AML with CAR-based immunotherapy poses major biological and clinical challenges, most of them derived from the unmet need to identify target antigens with expression restricted to the AML blast without compromising the viability of the normal hematopoietic stem cell counterpart. Although those limitations have hampered CAR-T cell therapy translation to the clinic, there are several clinical trials where target antigens, such as CD123, CLL-1 or CD33 are being used to treat AML patients showing promising results. Moreover, there are continuing efforts to enhance the specificity and efficacy of CAR-T cell therapy in AML. These endeavors encompass the exploration of novel avenues, including the development of dual CAR-T cells and next-generation CAR-T cells, as well as the utilization of gene editing tools to mitigate off-tumor toxicities. In this review, we will summarize the ongoing clinical studies and the early clinical results reported with CAR-T cells in AML, as well as highlight CAR-T cell limitations and the most recent approaches to overcome these barriers. We will also discuss how and when CAR-T cells should be used in the context of AML.

Multi-centers experience using therapeutic plasma exchange for corticosteroid/tocilizumab-refractory cytokine release syndrome following CAR-T therapy

The chimeric antigen receptor T (CAR-T) cell therapy significantly enhances the prognosis of various hematologic malignancies; however, the systemic expansion of CAR-T cells also gives rise to severe cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). Despite the successful application of corticosteroids and tocilizumab in alleviating severe CRS in most patients, there are still individuals who experience life-threatening CRS without responding to the aforementioned therapies. In our retrospective cohort, we conducted an analysis of clinical and laboratory parameters, including inflammatory cytokines, in 17 patients from three centers who underwent therapeutic plasma exchange (TPE) for refractory CRS with or without ICANS following CAR-T products treatment. Our findings demonstrate a significant improvement in both clinical symptoms and laboratory parameters subsequent to TPE treatment. The rapid decrease in temperature and levels of inflammatory indexes indicates the remarkable scavenging efficacy of TPE against cytokine storm following CAR-T therapy. In conclusion, TPE may serve as a valuable and safe adjunct to corticosteroids and tocilizumab in the management of severe CRS resulting from CAR-T cell infusion. We eagerly await further prospective studies to validate this finding.

Chimeric antigen receptor T-cell therapy in hematologic malignancies: Successes, challenges, and opportunities

The success of chimeric antigen receptor T-cell (CAR-T) therapy in hematologic malignancies has realized a longstanding effort toward harnessing the immune system to fight cancer in a truly personalized fashion. Second generation chimeric antigen receptors (CAR) incorporating co-stimulatory molecules like 4-1BB or CD28 were able to overcome some of the hindrances with initial CAR constructs resulting in efficacious products. Many second-generation CAR-T products have been approved in the treatment of relapsed/refractory hematologic malignancies including multiple myeloma (MM), non-Hodgkin lymphoma (NHL), and acute lymphoblastic leukemia. However, challenges remain in optimizing the manufacturing, timely access, limiting the toxicity from CAR-T infusions and improving sustainability of responses derived with CAR-T therapy. Here, we summarize the clinical trial data leading to approval CAR-T therapies in MM and NHL, discuss the limitations with current CAR-T therapy strategies and review emerging strategies for overcoming these limitations.

Towards a structural and functional analysis of the immunoglobulin-fold proteome

The immunoglobulin fold (Ig fold) domain is a super-secondary structural motif consisting of a sandwich with two layers of β-sheets that is present in many proteins with very diverse biological functions covering a wide range of physiological processes. This domain presents a modular architecture built with β strands connected by variable length loops that has a highly conserved structural core of four β-strands and quite variable β-sheet extensions in the two sandwich layers that enable both divergent and convergent evolutionary mechanisms in the known Ig fold proteome. The central role of this Ig fold's structural plasticity in the evolutionary success of antibodies in our immune system is well established. Nature has also utilized this Ig fold in all domains of life in many different physiological contexts that go way beyond the immune system. Here we will present a structural and functional overview of the utilization of the Ig fold in different biological processes and in different cellular contexts to highlight some of the innumerable ways that this structural motif can interact in multidomain proteins to enable their diversity of functions. This includes shareable specific protein structure visualizations behind those functions that serve as starting points for further explorations of the biomolecular interactions spanning the Ig fold proteome. This overview also highlights how this Ig fold is being utilized through natural adaptation, engineering, and even building from scratch for a range of biotechnological applications.

An overview of the therapeutic strategies for neoplastic meningitis due to breast cancer: when and why?

INTRODUCTION

Neoplastic meningitis (NM), also known as leptomeningeal carcinomatosis, is characterized by the infiltration of tumor cells into the meninges, and poses a significant therapeutic challenge owing to its aggressive nature and limited treatment options. Breast cancer is a common cause of NM among solid tumors, further highlighting the urgent need to explore effective therapeutic strategies. This review aims to provide insights into the evolving landscape of NM therapy in breast cancer by collating existing research, evaluating current treatments, and identifying potential emerging therapeutic options.

AREAS COVERED

This review explores the clinical features, therapeutic strategies, recent advances, and challenges of managing NM in patients with breast cancer. Its management includes multimodal strategies, including systemic and intrathecal chemotherapy, radiation therapy, and supportive care. This review also emphasizes targeted drug options and optimal drug concentrations, and discusses emerging therapies. Additionally, it highlights the variability in treatment outcomes and the potential of combination regimens to effectively manage NM in breast cancer.

EXPERT OPINION

Challenges in treating NM include debates over clinical trial end points and the management of adverse effects. Drug resistance and low response rates are significant hurdles, particularly inHER2-negative breast cancer. The development of more precise and cost-effective medications with improved selectivity is crucial. Additionally, global efforts are needed for infrastructure development and cancer control considering the diverse nature of the disease.

CAR-T Therapy in Relapsed Refractory Multiple Myeloma

Multiple myeloma is a plasma cell neoplasm. The emergence of proteasome inhibitors, immunomodulatory drugs, and anti-CD38 monoclonal antibodies has improved the prognosis of multiple myeloma patients. However, some patients are still insensitive to conventional therapy or frequently relapse after remission. Chemotherapy based on proteasome inhibitors or immunomodulatory drugs is ineffective in controlling the progression of relapsed refractory multiple myeloma. No consensus has been reached on treating relapsed refractory multiple myeloma to date. Recently chimeric antigen receptor T cells therapy has shown promising results that could achieve rapid remissions of patients and improve their prognoses. Additionally, most patients in chimeric antigen receptor T cell clinical trials were triple-refractory multiple myeloma patients, indicating that chimeric antigen receptor T cell immunotherapy could overcome drug resistance to new drugs. Since single immunotherapies are prone to acquired resistance, combination immunotherapies based on emerging immunotherapies may solve this issue. Achieving complete remission and minimal residual disease negative status as soon as possible is beneficial to patients. This paper reviewed the main chimeric antigen receptor T cell products in relapsed refractory multiple myeloma, and it explained the drug resistance mechanism and improvement methods of chimeric antigen receptor T cells therapy. This review summarized the best beneficiaries of chimeric antigen receptor T cell therapy and the salvage treatment of disease recurrence after chimeric antigen receptor T cell therapy, providing some ideas for the clinical application of chimeric antigen receptor T cells.

Advancements in chimeric antigen receptor-expressing T-cell therapy for glioblastoma multiforme: Literature review and future directions

Glioblastoma multiforme (GBM) is an aggressive cancer that has been difficult to treat and often requires multimodal therapy consisting of surgery, radiotherapy, and chemotherapy. Chimeric antigen receptor-expressing (CAR-T) cells have been efficacious in treating hematological malignancies, resulting in several FDA-approved therapies. CAR-T cells have been more recently studied for the treatment of GBM, with some promising preclinical and clinical results. The purpose of this literature review is to highlight the commonly targeted antigens, results of clinical trials, novel modifications, and potential solutions for challenges that exist for CAR-T cells to become more widely implemented and effective in eradicating GBM.

Engineered Adoptive T-Cell Therapies for Breast Cancer: Current Progress, Challenges, and Potential

Breast cancer remains a significant health challenge, and novel treatment approaches are critically needed. This review presents an in-depth analysis of engineered adoptive T-cell therapies (E-ACTs), an innovative frontier in cancer immunotherapy, focusing on their application in breast cancer. We explore the evolving landscape of chimeric antigen receptor (CAR) and T-cell receptor (TCR) T-cell therapies, highlighting their potential and challenges in targeting breast cancer. The review addresses key obstacles such as target antigen selection, the complex breast cancer tumor microenvironment, and the persistence of engineered T-cells. We discuss the advances in overcoming these barriers, including strategies to enhance T-cell efficacy. Finally, our comprehensive analysis of the current clinical trials in this area provides insights into the future possibilities and directions of E-ACTs in breast cancer treatment.

Rank aggregation of independent genetic screen results highlights new strategies for adoptive cellular transfer therapy of cancer

Efficient intratumoral infiltration of adoptively transferred cells is a significant barrier to effectively treating solid tumors with adoptive cellular transfer (ACT) therapies. Our recent forward genetic, whole-genome screen identified T cell-intrinsic gene candidates that may improve tumor infiltration of T cells. Here, results are combined with five independent genetic screens using rank aggregation to improve rigor. This resulted in a combined total of 1,523 candidate genes - including 1,464 genes not currently being evaluated as therapeutic targets - that may improve tumor infiltration of T cells. Gene set enrichment analysis of a published human dataset shows that these gene candidates are differentially expressed in tumor infiltrating compared to circulating T cells, supporting translational potential. Importantly, adoptive transfer of T cells overexpressing gain-of-function candidates (AAK1ΔN125, SPRR1B, and EHHADH) into tumor-bearing mice resulted in increased T cell infiltration into tumors. These novel gene candidates may be considered as potential therapeutic candidates that can aid adoptive cellular therapy in improving T cell infiltration into solid tumors.

Leukapheresis for CAR-T cell production and therapy

Chimeric antigen receptor (CAR) T-cell therapy is an effective, individualized immunotherapy, and novel treatment for hematologic malignancies. Six commercial CAR-T cell products are currently approved for lymphatic malignancies and multiple myeloma. In addition, an increasing number of clinical centres produce CAR-T cells on-site, which enable the administration of CAR-T cells on site. The CAR-T cell products are either fresh or cryopreserved. Manufacturing CAR-T cells is a complicated process that begins with leukapheresis to obtain T cells from the patient's peripheral blood. An optimal leukapheresis product is crucial step for a successful CAR-T cell therapy; therefore, it is imperative to understand the factors that may affect the quality or T cells. The leukapheresis for CAR-T cell production is well tolerated and safe for both paediatric and adult patients and CAR-Τ cell therapy presents high clinical response rate in many studies. CAR-T cell therapy is under continuous improvement, and it has transformed into an almost standard procedure in clinical haematology and stem cell transplantation facilities that provide both autologous and allogeneic stem cell transplantations. In patients suffering from advanced haematological malignancies, CAR-T cell therapy shows incredible antitumor efficacy. Even after a single infusion of autologous CD19-targeting CAR-T cells in patients with relapsed or refractory diffuse large B cell lymphoma (DLBCL) and acute lymphoblastic leukaemia (ALL), long lasting remission is observed, and a fraction of the patients are being cured. Future novel constructs are being developed with better T cell persistence and better expansion. New next-generation CAR-T cells are currently designed to avoid toxicities such as cytokine release syndrome and neurotoxicity.

Recruiting In Vitro Transcribed mRNA against Cancer Immunotherapy: A Contemporary Appraisal of the Current Landscape

Over 100 innovative in vitro transcribed (IVT)-mRNAs are presently undergoing clinical trials, with a projected substantial impact on the pharmaceutical market in the near future. Τhe idea behind this is that after the successful cellular internalization of IVT-mRNAs, they are subsequently translated into proteins with therapeutic or prophylactic relevance. Simultaneously, cancer immunotherapy employs diverse strategies to mobilize the immune system in the battle against cancer. Therefore, in this review, the fundamental principles of IVT-mRNA to its recruitment in cancer immunotherapy, are discussed and analyzed. More specifically, this review paper focuses on the development of mRNA vaccines, the exploitation of neoantigens, as well as Chimeric Antigen Receptor (CAR) T-Cells, showcasing their clinical applications and the ongoing trials for the development of next-generation immunotherapeutics. Furthermore, this study investigates the synergistic potential of combining the CAR immunotherapy and the IVT-mRNAs by introducing our research group novel, patented delivery method that utilizes the Protein Transduction Domain (PTD) technology to transduce the IVT-mRNAs encoding the CAR of interest into the Natural Killer (NK)-92 cells, highlighting the potential for enhancing the CAR NK cell potency, efficiency, and bioenergetics. While IVT-mRNA technology brings exciting progress to cancer immunotherapy, several challenges and limitations must be acknowledged, such as safety, toxicity, and delivery issues. This comprehensive exploration of IVT-mRNA technology, in line with its applications in cancer therapeutics, offers valuable insights into the opportunities and challenges in the evolving landscape of cancer immunotherapy, setting the stage for future advancements in the field.

Chimeric Antigen Receptor T Cell Therapy in Acute Myeloid Leukemia: Trials and Tribulations

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy that is often associated with relapse and drug resistance after standard chemotherapy or targeted therapy, particularly in older patients. Hematopoietic stem cell transplants are looked upon as the ultimate salvage option with curative intent. Adoptive cell therapy using chimeric antigen receptors (CAR) has shown promise in B cell malignancies and is now being investigated in AML. Initial clinical trials have been disappointing in AML, and we review current strategies to improve efficacy for CAR approaches. The extensive number of clinical trials targeting different antigens likely reflects the genetic heterogeneity of AML. The limited number of patients reported in multiple early clinical studies makes it difficult to draw conclusions about CAR safety, but it does suggest that the efficacy of this approach in AML lags behind the success observed in B cell malignancies. There is a clear need not only to improve CAR design but also to identify targets in AML that show limited expression in normal myeloid lineage cells.

CAR-T Cell Therapy: From the Shop to Cancer Therapy

Cancer is a worldwide health problem. Nevertheless, new technologies in the immunotherapy field have emerged. Chimeric antigen receptor (CAR) technology is a novel biological form to treat cancer; CAR-T cell genetic engineering has positively revolutionized cancer immunotherapy. In this paper, we review the latest developments in CAR-T in cancer treatment. We present the structure of the different generations and variants of CAR-T cells including TRUCK (T cells redirected for universal cytokine killing. We explain the approaches of the CAR-T cells manufactured ex vivo and in vivo. Moreover, we describe the limitations and areas of opportunity for this immunotherapy and the current challenges of treating hematological and solid cancer using CAR-T technology as well as its constraints and engineering approaches. We summarize other immune cells that have been using CAR technology, such as natural killer (NK), macrophages (M), and dendritic cells (DC). We conclude that CAR-T cells have the potential to treat not only cancer but other chronic diseases.

Induced Pluripotent Stem Cell-Derived Chimeric Antigen Receptor T Cells: The Intersection of Stem Cells and Immunotherapy

Chimeric antigen receptor (CAR) T cell therapy is a promising cell-based immunotherapy applicable to various cancers. High cost of production, immune rejection, heterogeneity of cell product, limited cell source, limited expandability, and relatively long production time have created the need to achieve a universal allogeneic CAR-T cell product for "off-the-shelf" application. Since the innovation of induced pluripotent stem cells (iPSCs) by Yamanaka et al., extensive efforts have been made to prepare an unlimited cell source for regenerative medicine, that is, immunotherapy. In the autologous grafting approach, iPSCs prepare the desired cell source for generating autologous CAR-T cells through more accessible and available sources. In addition, generating iPSC-derived CAR-T cells is a promising approach to achieving a suitable source for producing an allogeneic CAR-T cell product. In brief, the first step is reprogramming somatic cells (accessible from peripheral blood, skin, etc.) to iPSCs. In the next step, CAR expression and T cell lineage differentiation should be applied in different arrangements. In addition, in an allogeneic manner, human leukocyte antigen/T cell receptor (TCR) deficiency should be applied in iPSC colonies. The allogeneic iPSC-derived CAR-T cell experiments showed that simultaneous performance of HLA/TCR deficiency, CAR expression, and T cell lineage differentiation could bring the production to the highest efficacy in generating allogeneic iPSC-derived CAR-T cells.

Bispecific T-Cell Engagers and Chimeric Antigen Receptor T-Cell Therapies in Glioblastoma: An Update

Glioblastoma is the most common malignant primary brain tumor in adults. The prognosis is extremely poor even with standard treatment of maximal safe resection, radiotherapy, and chemotherapy. Recurrence is inevitable within months, and treatment options are very limited. Chimeric antigen receptor T-cell therapy (CART) and bispecific T-cell engagers (TCEs) are two emerging immunotherapies that can redirect T-cells for tumor-specific killing and have shown remarkable success in hematological malignancies and been under extensive study for application in glioblastoma. While there have been multiple clinical trials showing preliminary evidence of safety and efficacy for CART, bispecific TCEs are still in the early stages of clinical testing, with preclinical studies showing very promising results. However, there are multiple shared challenges that need to be addressed in the future, including the route of delivery, antigen escape, the immunosuppressive tumor microenvironment, and toxicity resulting from the limited choice of tumor-specific antigens. Efforts are underway to optimize the design of both these treatments and find the ideal combination therapy to overcome these challenges. In this review, we describe the work that has been performed as well as novel approaches in glioblastoma and in other solid tumors that may be applicable in the future.