Elimination Of Tumor Cells Research Articles

Synthetic Cells and Molecules in Cellular Immunotherapy.

Cellular immunotherapy has emerged as an exciting strategy for cancer treatment, as it aims to enhance the body's immune response to tumor cells by engineering immune cells and designing synthetic molecules from scratch. Because of the cytotoxic nature, abundance in peripheral blood, and maturation of genetic engineering techniques, T cells have become the most commonly engineered immune cells to date. Represented by chimeric antigen receptor (CAR)-T therapy, T cell-based immunotherapy has revolutionized the clinical treatment of hematological malignancies. However, serious side effects and limited efficacy in solid tumors have hindered the clinical application of cellular immunotherapy. To address these limitations, various innovative strategies regarding synthetic cells and molecules have been developed. On one hand, some cytotoxic immune cells other than T cells have been engineered to explore the potential of targeted elimination of tumor cells, while some adjuvant cells have also been engineered to enhance the therapeutic effect. On the other hand, diverse synthetic cellular components and molecules are added to engineered immune cells to regulate their functions, promoting cytotoxic activity and restricting side effects. Moreover, novel bioactive materials such as hydrogels facilitating the delivery of therapeutic immune cells have also been applied to improve the efficacy of cellular immunotherapy. This review summarizes the innovative strategies of synthetic cells and molecules currently available in cellular immunotherapies, discusses the limitations, and provides insights into the next generation of cellular immunotherapies.

Engineered poly(A)-surrogates for translational regulation and therapeutic biocomputation in mammalian cells

Here, we present a gene regulation strategy enabling programmable control over eukaryotic translational initiation. By excising the natural poly-adenylation (poly-A) signal of target genes and replacing it with a synthetic control region harboring RNA-binding protein (RBP)-specific aptamers, cap-dependent translation is rendered exclusively dependent on synthetic translation initiation factors (STIFs) containing different RBPs engineered to conditionally associate with different eIF4F-binding proteins (eIFBPs). This modular design framework facilitates the engineering of various gene switches and intracellular sensors responding to many user-defined trigger signals of interest, demonstrating tightly controlled, rapid and reversible regulation of transgene expression in mammalian cells as well as compatibility with various clinically applicable delivery routes of in vivo gene therapy. Therapeutic efficacy was demonstrated in two animal models. To exemplify disease treatments that require on-demand drug secretion, we show that a custom-designed gene switch triggered by the FDA-approved drug grazoprevir can effectively control insulin expression and restore glucose homeostasis in diabetic mice. For diseases that require instantaneous sense-and-response treatment programs, we create highly specific sensors for various subcellularly (mis)localized protein markers (such as cancer-related fusion proteins) and show that translation-based protein sensors can be used either alone or in combination with other cell-state classification strategies to create therapeutic biocomputers driving self-sufficient elimination of tumor cells in mice. This design strategy demonstrates unprecedented flexibility for translational regulation and could form the basis for a novel class of programmable gene therapies in vivo.

Interplay between the oxidation process and cytotoxic effects of antimonene nanomaterials.

Pnictogen nanomaterials have recently attracted researchers' attention owing to their promising properties in the field of electronic, energy storage, and nanomedicine applications. Moreover, especially in the case of heavy pnictogens, their chemistry allows for nanomaterial synthesis using both top-down and bottom-up approaches, yielding materials with remarkable differences in terms of morphology, size, yield, and properties. In this study, we carried out a comprehensive structural and spectroscopic characterization of antimony-based nanomaterials (Sb-nanomaterials) obtained by applying different production methodologies (bottom-up and top-down routes) and investigating the influence of the synthesis on their oxidation state and stability in a biological environment. Indeed, in situ XANES/EXAFS studies of Sb-nanomaterials incubated in cell culture media were carried out, unveiling a different oxidation behavior. Furthermore, we investigated the cytotoxic effects of Sb-nanomaterials on six different cell lines: two non-cancerous (FSK and HEK293) and four cancerous (HeLa, SKBR3, THP-1, and A549). The results reveal that hexagonal antimonene (Sb-H) synthesized using a colloidal approach oxidizes the most and faster in cell culture media compared to liquid phase exfoliated (LPE) antimonene, suffering acute degradation and anticipating well-differentiated toxicity from its peers. In addition, the study highlights the importance of the synthetic route for the Sb-nanomaterials as it was observed to influence the chemical evolution of Sb-H into toxic Sb oxide species, playing a critical role in its ability to rapidly eliminate tumor cells. These findings provide insights into the mechanisms underlying the dark cytotoxicity of Sb-H and other related Sb-nanomaterials, underlining the importance of developing therapies based on controlled and on-demand nanomaterial oxidation.

Hybrid hydrogels based on agarose, halloysite nanotubes and polyvinyl alcohol: An excellent nanocarrier for controlled release of 5-fluorouracil

Nanotechnology, rather than traditional medicinal procedures like chemotherapy, now helps to reduce adverse effects. There is a great demand for a biocompatible nanocarrier with a long half-life, high bioavailability, and capable of imaging cells and targeting them selectively. A procedure known as water-in-oil-in-water (W/O/W) emulsification was employed to produce hybrid nanohydrogels containing agarose, polyvinyl alcohol, halloysite nanotubes, and 5-fluorouracil (AGA-PVA-HNT@5-Fu) which can be highly effective for decreasing the particle size of nanohydrogels and improving their uniformity. These hydrogels were produced to specifically target and administer the 5-Fu anti-cancer drug for the treatment of breast cancer. Following the evaluation of physicochemical characteristics, both a substantial drug loading and efficient trapping were accomplished. The nanohydrogels displayed a zeta potential of −38.4 mV indicative of a good stability due to the usage of span 80. Based on the drug release profile conducted in vitro, it was observed that AGA-PVA-HNT@5-Fu released the medication in a regulated way. By using MTT and flow cytometry analysis, it was found that AGA-PVA-HNT@5-Fu could effectively eliminate tumor cells, while the blank nanoparticles proved to be biocompatible. The results indicate that hybrid nanohydrogels based on AGA-PVA-HNT@5-Fu can be utilized as nanohydrogels for treating breast cancer.

Advances in CAR-NK cell therapy for hematological malignancies.

Chimeric antigen receptor T (CAR-T) cell therapy has revolutionized the treatment of hematological malignancies, demonstrably improving patient outcomes and prognosis. However, its application has introduced new challenges, such as safety concerns, off-target toxicities, and significant costs. Natural killer (NK) cells are crucial components of the innate immune system, capable of eliminating tumor cells without prior exposure to specific antigens or pre-activation. This inherent advantage complements the limitations of T cells, making CAR-NK cell therapy a promising avenue for hematological tumor immunotherapy. In recent years, preclinical and clinical studies have yielded preliminary evidence supporting the safety and efficacy of CAR-NK cell therapy in hematological malignancies, paving the way for future advancements in immunotherapy. This review aims to succinctly discuss the characteristics, significant therapeutic progress, and potential challenges associated with CAR-NK cell therapy.

Self-adjuvant Astragalus polysaccharide-based nanovaccines for enhanced tumor immunotherapy: a novel delivery system candidate for tumor vaccines.

The study of tumor nanovaccines (NVs) has gained interest because they specifically recognize and eliminate tumor cells. However, the poor recognition and internalization by dendritic cells (DCs) and insufficient immunogenicity restricted the vaccine efficacy. Herein, we extracted two molecular-weight Astragalus polysaccharides (APS, 12.19 kD; APSHMw, 135.67 kD) from Radix Astragali and made them self-assemble with OVA257-264 directly forming OVA/APS integrated nanocomplexes through the microfluidic method. The nanocomplexes were wrapped with a sheddable calcium phosphate layer to improve stability. APS in the formed nanocomplexes served as drug carriers and immune adjuvants for potent tumor immunotherapy. The optimal APS-NVs were approximately 160 nm with uniform size distribution and could remain stable in physiological saline solution. The FITC-OVA in APS-NVs could be effectively taken up by DCs, and APS-NVs could stimulate the maturation of DCs, improving the antigen cross-presentation efficiency in vitro. The possible mechanism was that APS can induce DC activation via multiple receptors such as dectin-1 and Toll-like receptors 2 and 4. Enhanced accumulation of APS-NVs both in draining and distal lymph nodes were observed following s.c. injection. Smaller APS-NVs could easily access the lymph nodes. Furthermore, APS-NVs could markedly promote antigen delivery efficiency to DCs and activate cytotoxic T cells. In addition, APS-NVs achieve a better antitumor effect in established B16-OVA melanoma tumors compared with the OVA+Alum treatment group. The antitumor mechanism correlated with the increase in cytotoxic T cells in the tumor region. Subsequently, the poor tumor inhibitory effect of APS-NVs on the nude mouse model of melanoma also confirmed the participation of antitumor adaptive immune response induced by NVs. Therefore, this study developed a promising APS-based tumor NV that is an efficient tumor immunotherapy without systemic side effects.

Prospects for Stimulating Autoimmunity and Developing New T Cells in Cancer Treatment

Any adverse problem or weakening of the body's immunity, such as HIV infection, long-term physical and mental stress, nutritional deficiencies, chemotherapy or major surgery, will make cells prone to cancer. The body's immune system also deteriorates with age, which may help understand how people's risk of developing cancer increases significantly as they age. If the body's immune system is no longer strong enough to completely destroy cancer cells, then we move from "eliminating" cancer to "balancing."The immune system is the body's protective network, consisting of immune cells, immune organs, and immune substances. It fights against foreign pathogens and mutated cells in the body to maintain the health of the human body's internal environment.
 Strictly speaking, patients with better physical conditions have higher and more powerful T cells, and the more T cells awakened by immune drugs, they are relatively more effective in eliminating tumor cells. Currently, T cell-based immunotherapy includes CAR-T therapy, TCR-T therapy, TILs therapy, and CTL therapy.

The tertiary lymphoid structure-related signature identified PTGDS in regulating PD-L1 and promoting the proliferation and migration of glioblastoma

BackgroundTertiary lymphoid structure (TLS) is a unique organ that carries out tumor cell elimination at tumor sites. It is continuously stimulated by inflammatory tumor signals and has been found to augment immunotherapy response. However, the detailed mechanisms behind it still need to be defined. MethodsTo explore and grasp the whole picture of TLS from a pan-cancer view, we collected nine TLS-related genes from previous studies. We performed a comprehensive analysis of 9637 samples across 33 tumor types accessed from The Cancer Genome Atlas (TCGA) database. EdU, Transwell, and flow cytometry were performed on the feature gene PTGDS in U251 cells. The regulatory role of PTGDS on PD-L1 expression and macrophage polarization was verified. ResultsAlteration analysis showed that mutations of TLS-related genes were widespread and relatively high. Clustering analysis based on the expression of these nine genes obtained two distinct clusters, with high EIF1AY and PTGDS in cluster 2 and better overall survival in cluster 1. To distinguish the two clusters, we utilized six machine learning algorithms and filtrated EIF1AY, PTGDS, SKAP1, and RBP5 as the characteristic genes, among which the former two genes were proved to be hazardous. PTGDS was found to regulate PD-L1 expression and also promoted the proliferation and migration of U251 cells. The knockdown of PTGDS could reduce the migration of macrophages and inhibit the polarization of macrophages into M2-phenotype. In addition, we established a TLS score to demonstrate patients’ TLS activity. The low TLS-score group overlapped with cluster 1 and displayed a better prognosis. Besides, the low TLS-score group was related to better immunotherapy responses. The HE staining of histopathological sections confirmed that the low TLS-score group exhibited higher infiltration of immune cells. ConclusionThis study reveals broad molecular, tumorigenic, and immunogenic signatures for further functional and therapeutic studies of tertiary lymphoid structure. The TLS score we established effectively predicted immunotherapy response and patients’ survival. Its future application and combination await more research.

Current advances in bacteria-based cancer immunotherapy.

As the understanding of the tumor microenvironment has deepened, immunotherapy has become a promising strategy for cancer treatment. In contrast to traditional therapies, immunotherapy is more precise and induces fewer adverse effects. In this field, some bacteria have attracted increased attention because of their natural ability to preferentially colonize and proliferate inside tumor sites and exert antitumor effects. Moreover, bacterial components may activate innate and adaptive immunity to resist tumor progression. However, the application of bacteria-based cancer immunotherapy is hampered by potential infection-associated toxicity and unpredictable behavior in vivo. Owing to modern developments in genetic engineering, bacteria can be modified to weaken their toxicity and enhance their ability to eliminate tumor cells or activate the antitumor immune response. This review summarizes the roles of bacteria in the tumor microenvironment, current strategies for bacterial engineering, and the synergistic efficiency of bacteria with other immunotherapies. In addition, the prospects and challenges of the clinical translation of engineered bacteria are summarized.

Supramolecular Peptide Amphiphile Nanospheres Reprogram Tumor-associated Macrophage to Reshape the Immune Microenvironment for Enhanced Breast Cancer Immunotherapy.

Tumor immunotherapy has become a research hotspot in cancer treatment, with macrophages playing a crucial role in tumor development. However, the tumor microenvironment restricts macrophage functionality, limiting their therapeutic potential. Therefore, modulating macrophage function and polarization is essential for enhancing tumor immunotherapy outcomes. Here, a supramolecular peptide amphiphile drug-delivery system (SPADS) is utilized to reprogram macrophages and reshape the tumor immune microenvironment (TIM) for immune-based therapies. The approach involved designing highly specific SPADS that selectively targets surface receptors of M2-type macrophages (M2-Mφ). These targeted peptides induced M2-Mφ repolarization into M1-type macrophages by dual inhibition of endoplasmic reticulum and oxidative stresses, resulting in improved macrophagic antitumor activity and immunoregulatory function. Additionally, TIM reshaping disrupted the immune evasion mechanisms employed by tumor cells, leading to increased infiltration, and activation of immune cells. Furthermore, the synergistic effect of macrophage reshaping and anti-PD-1 antibody (aPD-1) therapy significantly improved the immune system's ability to recognize and eliminate tumor cells, thereby enhancing tumor immunotherapy efficacy. SPADS utilization also induced lung metastasis suppression. Overall, this study demonstrates the potential of SPADS to drive macrophage reprogramming and reshape TIM, providing new insights, and directions for developing more effective immunotherapeutic approaches in cancer treatment.

Effect of the Cold Atmospheric Plasma Technology for Treatment the Cancer Diseases in the Human: A literature Review

CAP is a form of plasma with a temperature below 104°F at the application site. There are a variety of techniques for producing CAP, including Atmospheric Pressure Plasma Jet, Dielectric Barrier Discharge, and plasma needle and pencil. Multiple gases can produce CAP, including Helium, Heliox, Nitrogen, Argon, and air. Due to CAP's ability to deactivate organisms, cause cell separation, and kill cancer cells, researchers are interested in identifying dental and oncological applications for the compound. CAP is an ionized gas at 25 Co; it produces ROS and RNS due to several factors such as U.V., ray, heat, and power electric effects. Plasma is a matter at (fourth state) formed at low pressure or high temperature. Often, it is described as an ionized gas produced by the polyatomic fragmentation or the subtraction of electrons from monatomic gas shells. CAP has an antitumor effect. The current study aims to shed light on CAP technology, its definition, types, general applications, and their applications in treating human cancer. CAP was effective in treating cancer and eliminating tumor cells. CAP may have a place in the therapy of cancer. CAP used for cancer therapy has many advantages as a therapeutic method due to its effects of high selectivity, non-toxicity, combination potential, and adaptability. CAP eradicates cancer cells and uses this technique as a clinical therapeutic option that is effective and safe.

Current use of bispecific antibodies to treat multiple myeloma.

Targeted immunotherapy has significantly improved the outcome of patients with hematological malignancies by leveraging the power of the immune system to eliminate tumor cells. In multiple myeloma (MM), bispecific T-cell engagers (BsAb) targeting B-cell maturation antigen (BCMA), G protein-coupled receptor, class C, group 5, member D (GPRC5D), and Fc receptor-like 5 (FcRL5) have already demonstrated remarkable clinical activity in triple-class refractory patients. However, responses to BsAb are not universal, and resistance often emerges while on therapy. Mechanisms mediating resistance are tumor intrinsic or immune dependent. Reported tumor intrinsic factors include antigenic loss (biallelic or functional) through deletions or mutations of target genes, increased soluble BCMA (for BCMA targeting BsAb), high tumor burden, and extramedullary disease. Immune-mediated resistance are largely dependent on T-cell fitness and tolerant immune environment. Understanding these mechanisms will allow the design of optimized BsAb therapy and an informed approach to sequencing and combining these molecules with other anti-MM agents and immune therapies.

Tumor-targeting hydroxyapatite nanoparticles for remodeling tumor immune microenvironment (TIME) by activating mitoDNA-pyroptosis pathway in cancer

In recent years, immunotherapy has emerged as a promising strategy for treating solid tumors, although its efficacy remains limited to a subset of patients. Transforming non-responsive “cold” tumor types into immuno-responsive “hot” ones is critical to enhance the efficacy of immune-based cancer treatments. Pyroptosis, a programmed cell death mechanism, not only effectively eliminates tumor cells but also triggers a potent inflammatory response to initiate anti-tumor immune activities. This sheds light on the potential of pyroptosis to sensitize tumors to immune therapy. Hence, it is urgent to explore and develop novel treatments (e.g., nanomedicines) which are capable of inducing pyroptosis. In this study, we constructed tumor-targeting nanoparticles (CS-HAP@ATO NPs) by loading atorvastatin (ATO) onto chondroitin sulfate (CS) modified hydroxyapatite (HAP) nanoparticles (CS-HAP). CS was strategically employed to target tumor cells, while HAP exhibited the capacity to release calcium ions (Ca2+) in response to the tumor microenvironment. Moreover, ATO disrupted the mitochondrial function, leading to intracellular energy depletion and consequential changes in mitochondrial membrane permeability, followed by the influx of Ca2+ into the cytoplasm and mitochondria. CS and HAP synergetically augmented mitochondrial calcium overload, inciting the production of substantial amount of reactive oxygen species (ROS) and the subsequent liberation of oxidized mitochondrial DNA (OX-mitoDNA). This intricate activation process promoted the assembly of inflammasomes, most notably the NLRP3 inflammasome, followed by triggering caspase-1 activation. The activated caspase-1 was able to induce gasderminD (GSDMD) protein cleavage and present the GSDM-N domain, which interacted with phospholipids in the cell membrane. Then, the cell membrane permeability was raised, cellular swelling was observed, and abundant cell contents and inflammatory mediators were released. Ultimately, this orchestrated sequence of events served to enhance the anti-tumor immunoresponse within the organism.

Abstract C079: Comprehensive immunophenotypic profiling sheds light on the dynamic interplay between immune cells in the 4T1 breast cancer model upon anti-PD1 and anti-CTLA4 immunotherapy

Abstract Immuno-oncology has revolutionized cancer treatment by harnessing the immune system to target and eliminate tumor cells. In this study, we employed a combination of fluorescence-activated cell sorting (FACS) and Cytek full spectrum flow cytometry to investigate the impact of anti-PD1 (programmed cell death protein 1) and anti-CTLA4 (cytotoxic T-lymphocyte-associated protein 4) treatments on the 4T1 breast cancer model. We comprehensively analyzed 25 surface markers on immune cells to gain insights into the dynamic changes induced by immunotherapy. The 4T1 murine breast cancer model is known for its aggressive and metastatic nature, resembling triple-negative breast cancer in humans. We established a syngeneic orthotopic tumor graft of 4T1 cells in immunocompetent mice and treated them individually with anti-PD1 or anti-CTLA4 antibodies and compared the results to the respective isotype controls. Using FACS, we characterized immune cell populations within the tumor microenvironment and spleenocytes at multiple time points (before treatment, day 5, and day 17) during the treatment course. The Cytek full spectrum flow cytometry platform allowed simultaneous measurement of 25 surface markers, enabling a detailed analysis of immune cell phenotypes and functional states in a single experiment. Our findings revealed significant alterations in the immune landscape following anti-PD1 or anti-CTLA4 treatments. We observed an increase in tumor-infiltrating lymphocytes (TILs) and specifically CD4+ as well as CD8+ T cell infiltration within the tumor, accompanied by upregulation of T cell activation markers, such as CD69, CD38, CD44, PD1 and CD25. The immune cell composition within 4T1 tumors included CD4+ and CD8+ TILs, as well as increased populations of monocytes and macrophages. Additionally, a decrease in regulatory T cells (TRegs) was observed, indicating a potential restoration of immune balance. Moreover, F4/80+ CD206+ tumor-associated macrophages (TAMs) were identified in the 4T1 tumors vs. the spleen. This was associated with increased granzyme B production by CD8+ T cells and a shift towards an effector memory phenotype, suggesting improved cytotoxic function. To gain insights into spatial infiltration patterns of immune cells, we performed Immunohistochemistry (IHC) stainings of various immune cell markers in the 4T1 tumors. In line with the FACS results, we observed increased immune cell infiltration in tumors treated with anti-PD1 and anti-CTLA4 antibodies. Our comprehensive immunophenotypic analysis, utilizing Cytek full spectrum flow cytometry and IHC sheds light on the dynamic interplay between immune cells and the 4T1 breast cancer model during anti-PD1 and anti-CTLA4 immunotherapy. These findings provide valuable insights into the mechanisms underlying the therapeutic efficacy of immune checkpoint blockade in this aggressive cancer model. Citation Format: Christos Nikolaou, Simon Heller, Stefan Kaulfuss, Carlo Stresemann, Alexandra Eichten, Oliver von Ahsen, Martin Lange. Comprehensive immunophenotypic profiling sheds light on the dynamic interplay between immune cells in the 4T1 breast cancer model upon anti-PD1 and anti-CTLA4 immunotherapy [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr C079.

CAR-T Cell Therapy for Classical Hodgkin Lymphoma.

Classical Hodgkin lymphoma (cHL) is a malignancy characterized by the presence of Hodgkin and Reed-Sternberg (HRS) cells within a complex tumor microenvironment (TME). Despite advances in conventional therapies, a subset of cHL patients experience relapse or refractory disease, necessitating the exploration of novel treatment strategies. Chimeric antigen receptor T cell (CAR-T cell) therapy has emerged as a promising approach for the management of cHL, harnessing the power of genetically modified T cells to recognize and eliminate tumor cells. In this article, we provide an overview of the pathogenesis of cHL, highlighting the key molecular and cellular mechanisms involved. Additionally, we discuss the rationale for the development of CAR-T cell therapy in cHL, focusing on the identification of suitable targets on HRS cells (such as CD30, CD123, LMP1, and LMP2A), clonotypic lymphoma initiating B cells (CD19, CD20), and cells within the TME (CD123, CD19, CD20) for CAR-T cell design. Furthermore, we explore various strategies employed to enhance the efficacy and safety of CAR-T cell therapies in the treatment of cHL. Finally, we present an overview of the results obtained from clinical trials evaluating the efficacy of CAR-T cell therapies in cHL, highlighting their potential as a promising therapeutic option. Collectively, this article provides a comprehensive review of the current understanding of cHL pathogenesis and the rationale for CAR-T cell therapy development, offering insights into the future directions of this rapidly evolving field.

Abstract B024: TrkB.T1 receptor promotes an immunosuppressive microenvironment driven by neutrophil recruitment in gliomas

Abstract Gliomas are the most common type of brain tumor in both children and adults. Communication between cancer cells and the brain tumor microenvironment (TME) is a fundamental component of brain cancer pathophysiology. Glioma cells release factors that function as chemoattractants and influence the TME. Reciprocally, the activity of neurons from the surrounding TME drives the proliferation and growth of glial malignancies through paracrine signaling, brain-derived neurotrophic factor (BDNF) being a key secreted factor. BDNF binds with high affinity to the tropomyosin receptor kinase B (TrkB). Recent work from our group has shown that the TrkB.T1 splice variant is upregulated in human gliomas. In addition, TrkB.T1 overexpression enhances the tumor aggressiveness in vivo and is associated with the downregulation of genes involved in facilitating tumor cell recognition and elimination in vitro. However, the role of TrkB.T1 splice variant in this bidirectional communication between glioma cells and the surrounding cells remains unknown. Our aim was to assess if increased levels of TrkB.T1 observed in gliomas harbor a role in modulating immune responses. Thus, we explored the immune cell heterogeneity associated with increased levels of TrkB.T1 in vivo using a glioma mouse model engineered with RCAS/tv-a technology. Tumors overexpressing TrkB.T1 show decreased overall immune infiltration but increased neutrophil recruitment. Neutrophils have been associated with unfavorable prognosis in gliomas, a decrease in the tumor-infiltrating effector lymphocytes, and worst patterns of response to immunotherapy. In fact, we also observe a decrease in the CD8+ population when TrkB.T1 is overexpressed, suggesting that TrkB.T1 might support an immunosuppressive microenvironment. Thus, we next explored in vitro the communication mechanisms associated with an increase in TrkB.T1 using 3T3 cells that were transduced with pLJM1-lentivirus to overexpress TrkB.T1. These cells were serum-starved and treated with BDNF and the conditioned media was subjected to a cytokine multiplex analysis. The results show that TrkB.T1 significantly increases key chemokine levels previously described to be involved in the recruitment of neutrophils. Taken together, this work shows that the highly expressed TrkB.T1 receptor in gliomas might support an immunosuppressive microenvironment through the recruitment of neutrophils and represents a potential target for modulating glioma-immune cell interactions needed to curb disease progression, and warrants further investigation. Citation Format: Leyre Merino-Galan, Sergio Ortiz-Espinosa, Matthew Hathaway, Ashmitha Rajendran, Hawa Larissa Jagana, Gabriel Rubio, Maryam Shabar, Noemi Reche-Ley, Siobhan S Pattwell. TrkB.T1 receptor promotes an immunosuppressive microenvironment driven by neutrophil recruitment in gliomas [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor Immunology and Immunotherapy; 2023 Oct 1-4; Toronto, Ontario, Canada. Philadelphia (PA): AACR; Cancer Immunol Res 2023;11(12 Suppl):Abstract nr B024.

EZH2-H3K27me3-mediated silencing of mir-139-5p inhibits cellular senescence in hepatocellular carcinoma by activating TOP2A

BackgroundEpigenetic alterations play an important role in hepatocellular carcinoma (HCC) development. Enhancer of zeste homolog 2 (EZH2) is a well-known epigenetic modifier that functions as an oncogene in tumors by promoting the H3K27me3-mediated transcriptional repression of tumor suppressor genes. “Senescent cells” has been proposed as a possible core component of the hallmarks of cancer conceptualization. Induction of cell senescence and targeted elimination of these senescent tumor cells are new strategies for tumor therapy. However, the role of EZH2 in regulating cellular senescence remains poorly understood.MethodsBioinformatics analyses suggested that EZH2 and DNA topoisomerase II alpha (TOP2A) are coexpressed in tumors, including HCC. Kyoto Encyclopedia of Genes and Genome (KEGG) pathway enrichment analyses and gene set enrichment analyses (GSEA) suggests a correlation of EZH2 and TOP2A expression with cellular senescence in HCC. MicroRNA (miRNA) inhibitor and mimics, siRNA, PLKO-shRNA, and plenti6.3-miR-139 were used to upregulate or downregulate the expression of target genes. CCK8, EdU, clone formation, and senescence-associated β-galactosidase (SA-β-gal) staining assays were performed to assess cell proliferation and cellular senescence phenotypes. Dual-luciferase reporter and chromatin immunoprecipitation assays were performed to investigate the targeted binding and inhibition of TOP2A 3′ untranslated region (UTR) by miR-139-5p and the DNA enrichment of miR139-5p by EZH2 and H3K27me3. BALB/c nude mice were used to establish a xenograft tumor model and verify the phenotypes upon EZH2 and TOP2A silencing and miR-139 overexpression in vivo. In addition, tissue microarrays were used to analyze the expression patterns and correlations among EZH2, TOP2A, and miR-139-5p expression in HCC.ResultsBioinformatics analysis revealed that EZH2 and TOP2A are coexpressed in HCC. In vitro gain- and loss-of-function experiments showed that inhibition of EZH2 and TOP2A induces cellular senescence and inhibits proliferation of HCC cells. In vivo tumorigenesis assays indicated that EZH2 and TOP2A knockdown inhibits tumorigenesis by inducing cellular senescence. Mechanistically, EZH2 promotes TOP2A expression by regulating the H3K27me3-mediated epigenetic silencing of miR-139-5p. TOP2A is a direct target of miR-139-5p, and inhibition of miR-139-5p can reverse the promotion by EZH2 of TOP2A expression. The overexpression of miR-139-5p induces cellular senescence and inhibits proliferation of HCC cells both in vitro and in vivo. Clinically, expression of EZH2 and TOP2A are higher in HCC tissues than in normal tissues, and this high coexpression indicates a worse outcome of patients with HCC. Moreover, expression of EZH2 and TOP2A is significantly correlated with tumor differentiation grade, tumor invasion, and TNM stage in HCC. miR-139-5p expression is lower in HCC tumors than in normal tissues and is correlated with better prognosis of HCC patients.ConclusionsOur study revealed the role of the EZH2/miR-139-5p/TOP2A axis in regulating cellular senescence and cell proliferation in HCC, enriching the molecular mechanisms of EZH2-mediated epigenetic regulation in HCC. Therefore, our results provide insight into the therapeutic potential of targeting EZH2 to induce cellular senescence and then destroy senescent cells for HCC.Graphic

A second-generation M1-polarized CAR macrophage with antitumor efficacy.

Chimeric antigen receptor (CAR) T cell therapies have successfully treated hematological malignancies. Macrophages have also gained attention as an immunotherapy owing to their immunomodulatory capacity and ability to infiltrate solid tumors and phagocytize tumor cells. The first-generation CD3ζ-based CAR-macrophages could phagocytose tumor cells in an antigen-dependent manner. Here we engineered induced pluripotent stem cell-derived macrophages (iMACs) with toll-like receptor 4 intracellular toll/IL-1R (TIR) domain-containing CARs resulting in a markedly enhanced antitumor effect over first-generation CAR-macrophages. Moreover, the design of a tandem CD3ζ-TIR dual signaling CAR endows iMACs with both target engulfment capacity and antigen-dependent M1 polarization and M2 resistance in a nuclear factor kappa B (NF-κB)-dependent manner, as well as the capacity to modulate the tumor microenvironment. We also outline a mechanism of tumor cell elimination by CAR-induced efferocytosis against tumor cell apoptotic bodies. Taken together, we provide a second-generation CAR-iMAC with an ability for orthogonal phagocytosis and polarization and superior antitumor functions in treating solid tumors relative to first-generation CAR-macrophages.

Genetics of Aberrant Immune Responses During Tumor Progression Among Iranian Population

The immune system has a critical tumor suppressor function via the detection and elimination of the tumor cells. Tumor cells' immune escaping is commonly observed during neoplastic transformations. Immune response suppression or aberrations facilitate immune escape that promotes tumor progression in distant or primary locations via epithelial-mesenchymal transition and angiogenesis, respectively. It has been reported that there is a rising trend of cancer incidence among the Iranian population. Since aberrant immune responses are involved in tumorigenesis; immunotherapeutic methods can be efficient for tumor cell elimination. In the present review, we discussed all of the immune-related genes that have been associated with tumor progression among the Iranian population to clarify the genetics of immune deficiency during tumor progression in this population. T regulatory and T helper related genes were the most frequently deregulated genes during tumor progression in the Iranian population. This review paves the way to suggest an immune-specific panel of genetic markers for diagnostic and immunotherapeutic purposes among Iranian cancer patients.

Development of dendritic cell loaded MAGE-A2 long peptide; a potential target for tumor-specific T cell-mediated prostate cancer immunotherapy

BackgroundProstate cancer (PCa) is the second leading cause of cancer-related deaths among men worldwide. Immunotherapy is an emerging treatment modality for cancers that harnesses the immune system’s ability to eliminate tumor cells. In particular, dendritic cell (DC) vaccines, have demonstrated promise in eliciting a tumor-specific immune response. In this study, we investigated the potential of using DCs loaded with the MAGE-A2 long peptide to activate T cell cytotoxicity toward PCa cell lines.MethodsHere, we generated DCs from monocytes and thoroughly characterized their phenotypic and functional properties. Then, DCs were pulsed with MAGE-A2 long peptide (LP) as an antigen source, and monitored for their transition from immature to mature DCs by assessing the expression levels of several costimulatory and maturation molecules like CD14, HLA-DR, CD40, CD11c, CD80, CD83, CD86, and CCR7. Furthermore, the ability of MAGE-A2 -LP pulsed DCs to stimulate T cell proliferation in a mixed lymphocyte reaction (MLR) setting and induction of cytotoxic T cells (CTLs) in coculture with autologous T cells were examined. Finally, CTLs were evaluated for their capacity to produce interferon-gamma (IFN-γ) and kill PCa cell lines (PC3 and LNCaP).ResultsThe results demonstrated that the antigen-pulsed DCs exhibited a strong ability to stimulate the expansion of T cells. Moreover, the induced CTLs displayed substantial cytotoxicity against the target cells and exhibited increased IFN-γ production during activation compared to the controls.ConclusionsOverall, this innovative approach proved efficacious in targeting PCa cell lines, showcasing its potential as a foundation for the development and improved PCa cancer immunotherapy.