Colorectal cancer (CRC), a major global health concern, necessitates innovative treatments. Chimeric antigen receptor (CAR) T cells have shown promises, yet they grapple with challenges. The spotlight pivots to the rising heroes: CAR natural killer (NK) cells, offering advantages such as higher safety profiles, cost-effectiveness, and efficacy against solid tumors. Nevertheless, the specific mechanisms underlying CAR NK cell trafficking and their interplay within the complex tumor microenvironment require further in-depth exploration. Herein, we provide insights into the design and engineering of CAR NK cells, antigen targets in CRC, and success in overcoming resistance mechanisms with an emphasis on the potential for clinical trials.
Colorectal Neoplasms/immunology* ; Humans ; Killer Cells, Natural/metabolism* ; Receptors, Chimeric Antigen/genetics* ; Immunotherapy, Adoptive/methods* ; Tumor Microenvironment/immunology* ; Animals

The remarkable efficacy of chimeric antigen receptor (CAR) T cell therapy in hematological malignancies has provided a solid basis for the therapeutic concept, wherein specific pathogenic cell populations can be eradicated by means of targeted recognition. During the past few years, CAR-based cell therapies have been extensively investigated in preclinical and clinical research across various non-tumor diseases, with particular emphasis in the treatment of autoimmune diseases (ADs), yielding significant advancements. The recent deployment of CD19-directed CAR T cells has induced long-lasting, drug-free remission in patients with systemic lupus erythematosus (SLE) and other systemic ADs, alongside a more profound immune reconstruction of B cell repertoire compared with conventional immunosuppressive agents and B cell-targeting biologics. Despite the initial success achieved by CAR T cell therapy, it is critical to acknowledge the divergences in its application between cancer and ADs. Through examining recent clinical studies and ongoing research, we highlight the transformative potential of this therapeutic approach in the treatment of SLE, while also addressing the challenges and future directions necessary to enhance the long-term efficacy and safety of CAR-based cell therapies in clinical practice.
Humans ; Lupus Erythematosus, Systemic/immunology* ; Receptors, Chimeric Antigen/metabolism* ; Immunotherapy, Adoptive/methods* ; Cell- and Tissue-Based Therapy/methods* ; Animals ; T-Lymphocytes/immunology*

BACKGROUND: Several studies have demonstrated the occurrence of secondary tumors as a rare but significant complication of chimeric antigen receptor T (CAR-T) cell therapy, underscoring the need for a detailed investigation. Given the limited variety of secondary tumor types reported to date, a comprehensive characterization of the various secondary tumors arising after CAR-T therapy is essential to understand the associated risks and to define the role of the immune microenvironment in malignant transformation. This study aims to characterize the immune microenvironment of a newly identified secondary tumor post-CAR-T therapy, to clarify its pathogenesis and potential therapeutic targets. METHODS: In this study, the bone marrow (BM) samples were collected by aspiration from the primary and secondary tumors before and after CD19 CAR-T treatment. The CD45 + BM cells were enriched with human CD45 microbeads. The CD45 + cells were then sent for 10× genomics single-cell RNA sequencing (scRNA-seq) to identify cell populations. The Cell Ranger pipeline and CellChat were used for detailed analysis. RESULTS: In this study, a rare type of secondary chronic myelomonocytic leukemia (CMML) were reported in a patient with diffuse large B-cell lymphoma (DLBCL) who had previously received CD19 CAR-T therapy. The scRNA-seq analysis revealed increased inflammatory cytokines, chemokines, and an immunosuppressive state of monocytes/macrophages, which may impair cytotoxic activity in both T and natural killer (NK) cells in secondary CMML before treatment. In contrast, their cytotoxicity was restored in secondary CMML after treatment. CONCLUSIONS This finding delineates a previously unrecognized type of secondary tumor, CMML, after CAR-T therapy and provide a framework for defining the immune microenvironment of secondary tumor occurrence after CAR-T therapy. In addition, the results provide a rationale for targeting macrophages to improve treatment strategies for CMML treatment.
Humans ; Lymphoma, Large B-Cell, Diffuse/therapy* ; Tumor Microenvironment/genetics* ; Antigens, CD19/metabolism* ; Leukemia, Myelomonocytic, Chronic/genetics* ; Immunotherapy, Adoptive/adverse effects* ; Male ; Single-Cell Analysis/methods* ; Female ; Sequence Analysis, RNA/methods* ; Receptors, Chimeric Antigen ; Middle Aged

Chimeric antigen receptor T (CAR-T) cells have reshaped the treatment landscape of hematological malignancies, offering a potentially curative option for patients. Despite these major milestones in the field of immuno-oncology, growing experience with CAR-T cells has also highlighted several limitations of this strategy. The production process of CAR-T cells is complex, time-consuming, and costly, thus leading to poor drug accessibility. The potential carcinogenic risk of viral transfection systems remains a matter of controversy. Treatment-related side effects, such as cytokine release syndrome, can be life-threatening. And the biggest challenge is the inadequate efficacy related to poor infiltration and retention of CAR-T cells in tumor tissues and impaired T cell activation caused by the immunosuppressive tumor microenvironment (TME). Innovative strategies are urgently needed to address these problems, and nanomedicine offers good solutions to these challenges. In this review, we provide a comprehensive summary of recent advancements in the application of nanomaterials to enhance CAR-T cell therapy. We examine the role of innovative nanoparticle-based delivery systems in the production of CAR-T cells, with a particular focus on polymeric delivery systems and lipid nanoparticles (LNPs). Furthermore, we explore various strategies for delivering immune stimulators, which significantly enhance the efficacy of CAR-T cells by modulating T cell viability and functionality or by reprogramming the immunosuppressive TME. In addition, we discuss several novel therapeutic approaches aimed at mitigating the adverse effects associated with CAR-T therapies. Finally, we offer an integrated perspective on the future challenges and opportunities facing CAR-T therapies.
Humans ; Nanomedicine/methods* ; Receptors, Chimeric Antigen/metabolism* ; Immunotherapy, Adoptive/methods* ; T-Lymphocytes/immunology* ; Nanoparticles/chemistry* ; Animals

The study aimed to construct the second and third generation chimeric antigen receptor T cells (CAR-T) targeting the c-mesenchymal-epithelial transition factor (c-Met) protein, and observe their killing effect on human serous ovarian cancer cell SKOV-3. The expression of MET gene in ovarian serous cystadenocarcinoma, the correlation between MET gene expression and the abundance of immune cell infiltration, and the effect of MET gene expression on the tissue function of ovarian serous cystadenocarcinoma were analyzed by bioinformatics. The expression of c-Met in ovarian cancer tissues and adjacent tissues was detected by immunohistochemical staining. The second and third generation c-Met CAR-T cells, namely c-Met CAR-T(2G/3G), were prepared by lentivirus infection, and the cell subsets and infection efficiency were detected by flow cytometry. Using CD19 CAR-T and activated T cells as control groups and A2780 cells with c-Met negative expression as Non target groups, the kill efficiency on SKOV-3 cells with c-Met positive expression, cytokine release and cell proliferation of c-Met CAR-T(2G/3G) were explored by lactate dehydrogenase (LDH) release, ELISA and CCK-8 respectively. The results showed that MET gene expression was significantly up-regulated in ovarian cancer tissues compared with normal tissues, which was consistent with the immunohistochemistry results. However, in all pathological stages, there was no obvious difference in MET expression and no correlation between MET gene expression and the race and age of ovarian cancer patients. The second generation and third generation c-Met CAR-T cells were successfully constructed. After lentivirus infection, the proportion of CD8⁺ T cells in c-Met CAR-T(2G) was upregulated, while there was no significant change in the cell subsets of c-Met CAR-T(3G). The LDH release experiment showed that the kill efficiency of c-Met CAR-T(2G/3G) on SKOV-3 increased with the increase of effect-target ratio. When the effect-target ratio was 20:1, the kill efficiency of c-Met CAR-T(2G) reached (42.02 ± 5.17)% (P < 0.05), and the kill efficiency of c-Met CAR-T(3G) reached (51.40 ± 2.71)% (P < 0.05). ELISA results showed that c-Met CAR-T released more cytokine compared to CD19 CAR-T and activated T cells (P < 0.05). Moreover, the cytokine release of c-Met CAR-T(3G) was higher than c-Met CAR-T(2G) (P < 0.01). The CCK-8 results showed that after 48 h, the cell number of c-Met CAR-T(2G) was higher than that of c-Met CAR-T(3G) (P < 0.01). In conclusion, both the second and third generation c-Met CAR-T can target and kill c-Met-positive SKOV-3 cells, with no significant difference. c-Met CAR-T(2G) has stronger proliferative ability, and c-Met CAR-T(3G) releases more cytokines.
Humans ; Female ; Ovarian Neoplasms/immunology* ; Proto-Oncogene Proteins c-met/metabolism* ; Receptors, Chimeric Antigen/immunology* ; Cell Line, Tumor ; Cystadenocarcinoma, Serous/immunology* ; T-Lymphocytes/immunology*

Objective To investigate the effect of ATP synthase inhibitory factor 1 (ATPIF1) on the antitumor activity of chimeric antigen receptor (CAR)-NK92 cells. Methods HER2-targeted CAR-NK92 cells with ATPIF1 overexpression or knockdown were constructed. CAR-positive expression rate was detected by flow cytometry. Cell proliferation capacity was measured using CCK-8 assay. Glycolytic capacity was analyzed by Seahorse metabolic analyzer. Mitochondrial membrane potential levels were detected using JC-1 probe. Target cell lysis rate was evaluated by firefly luciferase reporter assay. Expression levels of CD107a, natural-killer group 2 member D (NKG2D), granzyme B (GzmB), perforin, and interleukin 2 (IL-2) were detected via flow cytometry. Quantitative real-time PCR was used to measure the expression of interferon-induced protein with tetratricopeptide repeats 1 (IFIT1), tumor necrosis factor α (TNF-α), ATPIF1, and hexokinase 1 (HK1). The impact of glycolytic inhibition by 2-Deoxy-D-glucose (2-DG) on CAR-NK92 antitumor capacity was examined. Results Successfully generated HER2-targeting control CAR-NK92 cells, as well as ATPIF1-overexpressing and ATPIF1 knockdown CAR-NK92 cells. The ATPIF1-overexpressing CAR-NK92 cells showed significantly enhanced target cell lysis rate, elevated expression levels of NKG2D and CD107a, increased secretion capacities of Granzyme B (GzmB) and IL-2, and upregulated mRNA expression levels of IFIT1 and TNF-α, while ATPIF1-knockdown cells exhibited opposite effects. ATPIF1 overexpression induced metabolic reprogramming in CAR-NK92 cells, manifested by significantly decreased mitochondrial membrane potential (δpsim), markedly upregulated HK1 mRNA expression, and enhanced basal glycolysis and glycolytic capacity. After glycolysis inhibition with 2-DG (5 μmol/L), both ATPIF1-overexpressing and knockdown CAR-NK92 cells showed no significant differences in NKG2D and CD107a expression levels compared to control cells. Conclusion ATPIF1 regulates the antitumor activity of CAR-NK92 cells through modulating glycolytic metabolism. Overexpression of ATPIF1 can enhance the antitumor efficacy of CAR-NK92 cells.
Humans ; Glycolysis ; Killer Cells, Natural/metabolism* ; Receptors, Chimeric Antigen/immunology* ; Granzymes/genetics* ; Hexokinase/metabolism* ; Cell Line, Tumor ; Interleukin-2/genetics* ; Cell Proliferation ; NK Cell Lectin-Like Receptor Subfamily K/genetics* ; Membrane Potential, Mitochondrial

Chimeric antigen receptor T cell (CAR-T) therapy has shown remarkable success in treating hematological malignancies. However, CAR-T therapy for solid tumors is still limited due to the unique solid-tumor microenvironment and heterogeneous target antigen expression, which leads to an urgent need of combining other therapies. At present, nano delivery system has become one of the most promising directions for the development of anti-tumor drugs. Based on the background of CAR-T and tumor treatment, we focus on the research progress of nanomedicine combined with CAR-T therapy, and systematically review the strategies and examples in recent years in the aspects of in vivo delivery of mRNA, regulation of tumor microenvironment, combination with photothermal therapy. And we also look forward to the future direction of this filed.
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Humans ; Receptors, Chimeric Antigen/therapeutic use* ; Pharmaceutical Preparations/metabolism* ; Antigens, Neoplasm/metabolism* ; Lung Neoplasms/metabolism* ; Neoplasms/metabolism* ; T-Lymphocytes ; Tumor Microenvironment ; Nanoparticles/therapeutic use*

T-lymphocyte tumors are a group of diseases containing various types of lymphatic system tumors, with strong heterogeneity and poor clinical outcomes. Chimeric antigen receptor T (CAR-T) cell therapy, as a new immune cell therapy, has made a breakthrough in the field of B-lymphocyte tumors. People are interested in the application prospect of this technique in the field of T-lymphocyte tumors. Some studies have shown that CAR-T cell therapy has made some progress in the treatment of T-lymphocyte tumors, and CAR-T for some targets has entered the stage of clinical trials. However, due to the characteristics of T cells, there are also many challenges. This article reviews the research and application of CAR-T cell therapy in T-lymphocyte tumors.
Humans ; T-Lymphocytes ; Receptors, Chimeric Antigen/metabolism* ; Neoplasms/metabolism* ; Immunotherapy, Adoptive/methods* ; Cell- and Tissue-Based Therapy

The aim of this study was to investigate the functional characteristics and in vitro specific killing effect of EGFRvIII CAR-T cells co-expressing interleukin-15 and chemokine CCL19, in order to optimize the multiple functions of CAR-T cells and improve the therapeutic effect of CAR-T cells targeting EGFRvIII on glioblastoma (GBM). The recombinant lentivirus plasmid was obtained by genetic engineering, transfected into 293T cells to obtain lentivirus and infected T cells to obtain the fourth generation CAR-T cells targeting EGFRvIII (EGFRvIII-IL-15-CCL19 CAR-T). The expression rate of CAR molecules, proliferation, chemotactic ability, in vitro specific killing ability and anti-apoptotic ability of the fourth and second generation CAR-T cells (EGFRvIII CAR-T) were detected by flow cytometry, cell counter, chemotaxis chamber and apoptosis kit. The results showed that compared with EGFRvIII CAR-T cells, EGFRvIII-IL-15-CCL19 CAR-T cells successfully secreted IL-15 and CCL19, and had stronger proliferation, chemotactic ability and anti-apoptosis ability in vitro (all P < 0.05), while there was no significant difference in killing ability in vitro. Therefore, CAR-T cells targeting EGFRvIII and secreting IL-15 and CCL19 are expected to improve the therapeutic effect of glioblastoma and provide an experimental basis for clinical trials.
Humans ; Receptors, Chimeric Antigen/metabolism* ; Glioblastoma/metabolism* ; Interleukin-15/metabolism* ; Chemokine CCL19/metabolism* ; Cell Line, Tumor ; T-Lymphocytes/metabolism*

Although the development of novel drugs has significantly improved the survival of patients with multiple myeloma (MM) over the past decades,the lack of effective therapeutic options for relapsed and refractory MM results in poor prognosis.The chimeric antigen receptor (CAR) T-cell therapy has achieved considerable progress in relapsed and refractory MM.Nevertheless,this therapy still has limitations such as cytokine release syndrome,neurotoxicity,and off-target effects.Natural killer (NK) cells,as a critical component of the innate immune system,play an essential role in tumor immunosurveillance.Therefore,CAR-modified NK (CAR-NK) cells are put forward as a therapeutic option for MM.The available studies have suggested that multiple targets can be used as specific therapeutic targets for CAR-NK cell therapy and confirmed their antitumor effects in MM cell lines and animal models.This review summarizes the anti-tumor mechanisms,biological characteristics,and dysfunction of NK cells in the MM tumor microenvironment,as well as the basic and clinical research progress of CAR-NK cells in treating MM.
Animals ; Receptors, Chimeric Antigen/metabolism* ; Multiple Myeloma/metabolism* ; Killer Cells, Natural/metabolism* ; Immunotherapy, Adoptive/methods* ; Tumor Microenvironment