Epigenetic mechanisms are involved in several cellular functions, and their role in the immune system is of prime importance. Histone deacetylases (HDACs) are an important set of enzymes that regulate and catalyze the deacetylation process. HDACs have been proven beneficial targets for improving the efficacy of immunotherapies. HDAC11 is an enzyme involved in the negative regulation of T cell functions. Here, we investigated the potential of HDAC11 downregulation using RNA interference in CAR-T cells to improve immunotherapeutic outcomes against prostate cancer. We designed and tested four distinct short hairpin RNA (shRNA) sequences targeting HDAC11 to identify the most effective one for subsequent analyses. HDAC11-deficient CAR-T cells (shD-NKG2D-CAR-T) displayed better cytotoxicity than wild-type CAR-T cells against prostate cancer cell lines. This effect was attributed to enhanced activation, degranulation, and cytokine release ability of shD-NKG2D-CAR-T when co-cultured with prostate cancer cell lines. Our findings reveal that HDAC11 interference significantly enhances CAR-T cell proliferation, diminishes exhaustion markers PD-1 and TIM3, and promotes the formation of T central memory TCM populations. Further exploration into the underlying molecular mechanisms reveals increased expression of transcription factor Eomes, providing insight into the regulation of CAR-T cell differentiation. Finally, the shD-NKG2D-CAR-T cells provided efficient tumor control leading to improved survival of tumor-bearing mice in vivo as compared to their wild-type counterparts. The current study highlights the potential of HDAC11 downregulation in improving CAR-T cell therapy. The study will pave the way for further investigations focused on understanding and exploiting epigenetic mechanisms for immunotherapeutic outcomes.

The limited expansion ability and functional inactivation of T cells within the solid tumor microenvironment are major problems faced during in the application of using tumor-infiltrating lymphocytes (TILs) in vivo. We sought to determine whether TILs carrying a PD-1-CD28-enhanced receptor and CD19 CAR could overcome this limitation and mediate tumor regression. First, anti-tumor effects of PD-1-CD28-enhanced receptor or CD19 CAR modified NY-ESO-1-TCR-T cells to mimic the TILs function (hereafter \"PD-1-CD28-TCR-T\" or \"CD19 CAR-TCR-T\" cells, respectively) were tested using the NY-ESO-1 over-expressed tumor cell line in vitro and in a tumor-bearing model. Furthermore, the safety and anti-tumor ability of S-TILs (TILs modified through transduction with a plasmid encoding the PD-1-CD28-T2A-CD19 CAR) were evaluated in vivo. PD-1-CD28-TCR-T cells showed a formidable anti-tumor ability that was not subject to PD-1/PD-L1 signaling in vivo. CD19 CAR-TCR-T cells stimulated with CD19+ B cells exhibited powerful expansion and anti-tumor abilities both in vitro and in vivo. Three patients with refractory solid tumors received S-TILs infusion. No treatment-related mortality was observed, and none of the patients experienced serious side effects. One patient with melanoma achieved a partial response, and two patients with colon or kidney cancer achieved long-term stable disease following S-TILs therapy. To the best of our knowledge, this is the first study describing the safety and efficacy of the adoptive transfer of autologous S-TILs to control disease in patients with advanced cancers, suggesting that S-TILs may be a promising alternative therapy for cancer.

Multiple myeloma (MM), marked by abnormal proliferation of plasma cells and production of monoclonal immunoglobulin heavy or light chains in the majority of patients, has traditionally been associated with poor survival, despite improvements achieved in median survival in all age groups since the introduction of novel agents. Survival has significantly improved with the development of new drugs and new treatment options, such as chimeric antigen receptor T-cell therapy (CAR-T), which have shown promise and given new hope in MM therapy. CARs are now classified as first-, second-, and third-generation CARs based on the number of monovalent to trivalent co-stimulatory molecules incorporated into their design. The scope of this review was relatively narrow because it was mainly about a comparison of the literature on the clinical application of CAR-T therapy in MM. Thus, our goal is to provide an overview of the new advances of CAR-T cells in the cure of MM, so in this review we looked at the progress of the clinical use of CAR-T cells in MM to try to provide a reference for their clinical use when managing MM.

BACKGROUND: Although anti-CD19 chimeric antigen receptor (CAR) T cell therapy was approved as a very effective salvage strategy in relapsed/refractory (R/R) B cell lymphoma, the experience in R/R gastrointestinal (GI) lymphoma is still insufficient.
METHODS: We summarized the efficacy and side effects of anti-CD19 CAR T-cell therapy in 12 patients with R/R GI lymphoma. Based on literature, the R/R GI lymphoma patients were divided into subgroups with different characteristics: Bulky/No bulky disease, Gastric/Gastrointestinal involvement, Gastrointestinal/Combined extra-gastrointestinal lesions, Ulcer/Lumps or nodules type, With/without gastrointestinal bleeding.
RESULTS: The objective response rate (ORR) was 66.67% in these 12 patients. The ORR was 83.33% in no bulky disease group, 80.00% in gastric involvement group, 100.00% in ulcer type group, and 80.00% in no gastrointestinal bleeding group. The CR rate was 33.33% in these 12 patients. The CR was 50.0% in no bulky disease group, 60.00% in gastric involvement group, and 80.00% in ulcer type group. The PFS and OS rate of the 12 patients at 6 months after infusion were 54.55% and 58.33%, respectively. The overall survival (OS) at 6 months was higher in no bulky disease group. There was no difference of the OS or the progression free survival (PFS) at 6 months between the other groups. The mean peak of CAR-T cells and Cytokine Release Syndrome (CRS) grade were higher in gastrointestinal lesions group. The mean peak of IFN-γ and CRS grade were higher in gastrointestinal bleeding group. Four out of six patients in group of gastrointestinal lesions group were patient with high tumor burden. Patients with gastrointestinal involvement only were at higher risk for gastrointestinal bleeding.
CONCLUSIONS: The ORR and CR of high tumor load, gastrointestinal involvement, lumps or nodules type and gastrointestinal bleeding group were lower. The CRS grade was higher in gastrointestinal lesions group and in gastrointestinal bleeding group. Patients with gastrointestinal involvement only were at higher risk for gastrointestinal bleeding.

The clinical efficacy of CAR-NK cells against CD19-expressing blood cancers has been demonstrated, and they have shown potential for treating solid tumors as well. However, the efficacy of CAR-NK cells for treating human oral tongue squamous cell carcinoma (OTSCC) has not been examined.
We assessed MUC1 expression in human OTSCC tissue and a cell line using immunohistochemistry and immunofluorescence. We constructed NK cells that express CAR targeted to MUC1 from pluripotent stem cells (iPSC-derived MUC1-targeted CAR-NK cells) and evaluated their effectiveness against OTSCC in vitro using the xCELLigence Real-Time Cell Analysis system and CCK8 assay, and in vivo by measuring xenograft growth daily in BNDG mice treated with MUC1-targeted CAR-NK cells. As controls, we used iPSC-derived NK cells and NK-free media, which were CAR-free and blank, respectively.
MUC1 expression was detected in 79.5% (66/83) of all OTSCC patients and 72.7% (24/33) of stage III and IV. In stage III and IV MUC1 positive OTSCC, 63.6% (21/33) and 48.5% (16/33) patients had a MUC1-positive cancer cell rate of more than 50% and 80%, respectively. The iPSC-derived MUC1-targeted CAR-NK cells exhibited significant cytotoxicity against MUC1-expressing OTSCC cells in vitro, in a time- and dose-dependent manner, and showed a significant inhibitory effect on xenograft growth compared to both the iPSC-derived NK cells and the blank controls. We observed no weight loss, severe hematological toxicity or NK cell-mediated death in the BNDG mice.
The MUC1-targeted CAR-NK cells had significant efficacy against human OTSCC, and their promising therapeutic response warrants further clinical trials.

CAR-T cell therapy, a novel therapeutic approach that has attracted much attention in the field of cancer treatment at present, has become the subject of many studies and has shown great potential in the treatment of hematological malignancies, such as leukemia and lymphoma. This study aims to analyze the characteristics of articles published on CAR-T cell therapy in the lymphoma field and explore the existing hotspots and frontiers. The relevant articles published from 2013 to 2022 were retrieved from the Web of Science Core Collection. CiteSpace, VOSviewer, Bibliometric online analysis platform, Microsoft Excel, and R software were used for bibliometric analysis and visualization. The number of publications related to the research has been increasing year by year, including 1023 articles and 760 reviews from 62 countries and regions, 2092 institutions, 1040 journals, and 8727 authors. The United States, China, and Germany are the main publishing countries in this research field. The top 10 institutions are all from the United States, the journal with the highest impact factor is BLOOD, the author with the most publications is Frederick L Locke, and the most influential author is Carl H June. The top three keywords are \"Lymphoma,\" \"Immunotherapy,\" and \"Therapy.\" \"Maude (2014)\" is the most cited and strongest burstiness reference over the past decade. This study provides a comprehensive bibliometric analysis of CAR-T cell therapy in lymphoma, which can help researchers understand the current research hotspots in this field, explore potential research directions, and identify future development trends.

Ovarian cancer (OC) is a highly aggressive gynecological malignancy prevalent worldwide. Most OC cases are typically diagnosed at advanced stages, which has led to a 5-year overall survival rate of less than 35% following conventional treatment. Furthermore, immune checkpoint inhibitor therapy has shown limited efficacy in the treatment of patients with OC, and CAR-T therapy has also demonstrated modest results owing to inadequate T cell infiltration. Therefore, novel strategies must be developed to enhance T cell persistence and trafficking within the OC tumor microenvironment.
In this study, we developed a novel adoptive T-cell therapy for ovarian cancer based on a chimeric antigen receptor structure. We used a ligand-receptor binding motif to enhance the therapeutic effect of targeting CA125. Since mesothelin can naturally bind to CA125 with high affinity, we concatenated the core-binding fragment of mesothelin with the 4-1BB and CD3ζ signal fragments to assemble a novel CA125-targeting chimeric receptor (CR). The CAR structure targeting CA125 derived from the 4H11 antibody was also constructed. CR- and CAR-encoding RNA were electroporated into T cells to evaluate their antitumor activity both in vitro and in vivo.
While CR-T or CAR-T cells exhibited moderate activity against two ovarian cancer cell lines, T cells co-expressing CR and CAR exhibited a superior killing effect compared to T cells expressing either CR or CAR alone. Furthermore, upon interaction with ovarian tumors, the ability of CR and CAR T cells to release activation markers and functional cytokines increased significantly. Similarly, CR and CAR co-expressing T cells persistently controlled the growth of transplanted ovarian cancer tumors in NSG mice and significantly prolonged the overall survival of tumor-challenged mice. Transcriptome sequencing revealed that the survival and cytotoxicity of T cells co-expressing CR and CAR were significantly altered compared with those of T cells expressing either CR or CAR.
Our findings demonstrate that CA125 targeting CR and CAR can synergistically kill ovarian cancer cells, indicating that CA125 targeting by the two binding motifs simultaneously in tumors may improve the therapeutic outcomes of ovarian cancer treatment.

CD19 chimeric antigen receptor (CAR) engineered NK cells have been used for treating patients with relapsed and/or refractory B cell malignancies and show encouraging outcomes and safety profile. However, the poor persistence of NK cells remains a major challenge for CAR NK cell therapy. Memory-like NK cells (MLNK) induced by IL-12, IL-15, and IL-18 have shown enhanced and prolonged responses to tumor re-stimulation, making them an attractive candidate for adoptive cellular immunotherapy. Here, we show efficient and stable gene delivery of CD19 CAR to memory-like NK cells using retroviral vectors with transduction efficiency comparable to those achieved with conventional NK cells. Analysis of surface molecules revealed a distinct phenotypic profile in CAR engineered memory-like NK cells (CAR MLNK), as evidenced by increased expression of CD94 and downregulation of NKp30 as well as KIR2DL1. Compared to conventional CAR NK cells, CAR MLNK cells exhibited significantly increased IFN-γ production and degranulation in response to CD19+ target cells, resulting in enhanced cytotoxic activity against CD19+ leukemia cells and lymphoma cells. Furthermore, memory properties induced by IL-12/-15/-18 improved the in vivo persistence of CAR MLNK cells and significantly suppressed tumor growth in a exnograft mouse model of lymphoma, leading to prolonged survival of CD19+ tumor-bearing mouse. Altogether, our data indicate that CD19 CAR engineered memory-like NK cells exhibited superior persistence and antitumor activity against CD19+ tumors, which might be an attractive approach for treating patient with relapse or refractory B cell malignancies.

Although anti-CD19 chimeric antigen receptor (CAR) T cell therapy has achieved satisfactory results in relapsed/refractory (R/R) follicular lymphoma (FL), patients with R/R FL and high-risk disease characteristics, previous hematopoietic stem cell transplantation, bulky disease, and progression of disease within 2 years (POD24) had a low complete response (CR). Twenty-seven patients with R/R FL, later disease stages, higher tumor burden, or higher previous treatment lines who had received Bruton tyrosine kinase (BTK) inhibitors before anti-CD19 CAR T cell therapy, or received BTK inhibitors as combination therapy, were included in this study. The clinical response and adverse events (AEs) in anti-CD19 CAR T cell therapy were observed. All patients with R/R FL who received BTK inhibitors combined with anti-CD19-CAR T cell therapy had later disease stages, higher tumor burden, and higher treatment lines than those who did not receive BTK inhibitor combination therapy. However, no difference in the clinical response was found between the two groups. The clinical response in the POD24 group was lower than that in the non-POD24 group; however, no difference in the clinical response was found between the FL and transformed FL (tFL) groups, between the follicular lymphoma international prognostic index (FLIPI) 1 1-2 and FLIPI 1 3-5 groups, and between the FLIPI 2 1-2 and FLIPI 2 3-5 groups. The mean anti-CD19 CAR T cell peak was higher in the CAR-T group with BTK inhibitor than in the CAR-T group without BTK inhibitor. Meanwhile, a higher proportion of patients in the non-POD24 group, FL group, and PR group achieved CR after 2 months. No difference in cytokine secretion was found between the CAR-T group with and without BTK inhibitors. It was higher in the non-POD24 group, FLIPI 1 3-5 group, and FLIPI 2 3-5 group. No difference in cytokine release syndrome and immune effector cell-associated neurotoxic syndrome grades was found between the CAR-T groups with or without BTK inhibitors and between the other groups. Poor prognostic factors, other than POD24, did not affect the clinical response to BTK inhibitors in combination with anti-CD19 CAR T cell therapy in patients with R/R FL. Therefore, BTK inhibitors combined with anti-CD19 CAR-T therapy may be an effective and safe approach for patients with R/R FL and high-risk factors.Trial registration: The study was registered at http://www.chictr.org.cn/index.aspx as ChiCTR-ONN-16009862 and http://www.chictr.org.cn/index.aspx as ChiCTR1800019622.

Dysregulation of the Notch signaling pathway, which is highly conserved across species, can drive aberrant epigenetic modification, transcription, and translation. Defective gene regulation caused by dysregulated Notch signaling often affects networks controlling oncogenesis and tumor progression. Meanwhile, Notch signaling can modulate immune cells involved in anti- or pro-tumor responses and tumor immunogenicity. A comprehensive understanding of these processes can help with designing new drugs that target Notch signaling, thereby enhancing the effects of cancer immunotherapy. Here, we provide an up-to-date and comprehensive overview of how Notch signaling intrinsically regulates immune cells and how alterations in Notch signaling in tumor cells or stromal cells extrinsically regulate immune responses in the tumor microenvironment (TME). We also discuss the potential role of Notch signaling in tumor immunity mediated by gut microbiota. Finally, we propose strategies for targeting Notch signaling in cancer immunotherapy. These include oncolytic virotherapy combined with inhibition of Notch signaling, nanoparticles (NPs) loaded with Notch signaling regulators to specifically target tumor-associated macrophages (TAMs) to repolarize their functions and remodel the TME, combining specific and efficient inhibitors or activators of Notch signaling with immune checkpoint blockers (ICBs) for synergistic anti-tumor therapy, and implementing a customized and effective synNotch circuit system to enhance safety of chimeric antigen receptor (CAR) immune cells. Collectively, this review aims to summarize how Notch signaling intrinsically and extrinsically shapes immune responses to improve immunotherapy.