Search Results (502)

Gastrointestinal (GI) malignancies are diverse and particularly challenging in terms of current immunotherapy but hold great opportunity for impact given that they constitute the highest cancer incidence and mortality rates worldwide. Traditional treatment options for solid GI malignancies include surgical intervention, chemotherapy, radiation, or a combination of these treatments. Emerging modalities within immunotherapy are anticipated to extend the results with conventional therapy by stimulating the patient’s own intrinsic potential for tumor-specific immunologic rejection. Combination regimens of chemotherapy and tumor-infiltrating lymphocyte (TIL) therapy in advanced colorectal cancer and pancreatic cancer, autologous monocyte therapy in advanced gastric cancer, and CAR-T therapy trained against GI-selective tumor antigens such as carcinoembryonic antigen are currently being studied. Clinical trials are underway to study the combination of various chemotherapeutic agents along with immunotherapy in the management of cholangiocarcinoma, hepatocellular carcinoma, and esophageal cancer. Alternative therapies are needed based on the tumor immune microenvironment, which can lead to a personalized approach to treatment. In this review, we discuss the current status of various modalities of immunotherapy in common GI malignancies, along with their mechanisms of immune activation and cancer suppression. We will also discuss the use of immunotherapy in less common solid GI malignancies and touch on recent advancements and clinical trials. Full article

In this review, we explore the complexities of objectively assessing the response to immunotherapy in mycosis fungoides (MF), a prevalent form of cutaneous T-cell lymphoma. The core challenge lies in distinguishing between reactive and malignant lymphocytes amidst treatment, particularly given the absence of uniform pathological biomarkers for MF. We highlight the vital role of emerging histological technologies, such as multispectral imaging and spatial transcriptomics, in offering a more profound insight into the tumor microenvironment (TME) and its dynamic response to immunomodulatory therapies. Drawing on parallels with melanoma—another immunogenic skin cancer—our review suggests that methodologies and insights from melanoma could be instrumental in refining the approach to MF. We specifically focus on the prognostic implications of various TME cell types, including CD8+ tumor-infiltrating lymphocytes, natural killer (NK) cells, and histiocytes, in predicting therapy responses. The review culminates in a discussion about adapting and evolving treatment response quantification strategies from melanoma research to the distinct context of MF, advocating for the implementation of novel techniques like high-throughput T-cell receptor gene rearrangement analysis. This exploration underscores the urgent need for continued innovation and standardization in evaluating responses to immunotherapies in MF, a field rapidly evolving with new therapeutic strategies. Full article

Lifileucel, a tumor-infiltrating lymphocyte (TIL) cell therapy approved for advanced melanoma, demonstrates promise for treating other solid tumors, including endometrial cancer (EC). The current study evaluates the feasibility of manufacturing TILs from EC tumors using Iovance’s proprietary 22-day Gen2 manufacturing process. Key parameters, including TIL yield, viability, immune phenotype, T-cell receptor clonality, and cytotoxic activity, were assessed. Of the 11 EC tumor samples processed at research scale, 10 (91%) successfully generated >1 × 10⁹ viable TIL cells, with a median yield of 1.1 × 10¹⁰ cells and a median viability of 82.8%. Of the four EC tumor samples processed at full scale, all achieved the pre-specified TVC and viability targets. Putative tumor-reactive T-cell clones were maintained throughout the manufacturing process. Functional reactivity was evidenced by the upregulation of 4-1BB in CD8+ T cells, OX40 in CD4+ T cells, and increased production of IFN-γ and TNF-α upon autologous tumor stimulation. Furthermore, antitumor activity was confirmed using an in vitro autologous tumor organoid killing assay. These findings demonstrate the feasibility of ex vivo TIL expansion from EC tumors. This study provides a rationale for the initiation of the phase II clinical trial IOV-END-201 (NCT06481592) to evaluate lifileucel in patients with advanced EC. Full article

Background/Objectives: This review discusses the resistance mechanisms in the tumor microenvironment (TME) of malignant melanoma that disrupt the efficacy of immune checkpoint inhibitors (ICIs). In this review, we focus on the roles of immune cells, including tumor-infiltrating lymphocytes (TILs), macrophages, dendritic cells, and other signaling pathways. We explore the interplay between innate and adaptive immunity in the TME and tumor intrinsic resistance mechanisms, such as β-catenin, which has future implications for the usage of ICIs in patients with therapy-resistant tumors. Methods: A total of 1052 studies were extracted from the PubMed database searching for keywords and phrases that included [melanoma AND immune checkpoint inhibitor resistance]. After a title/abstract and full-text review, 101 studies were identified that fit the inclusion/exclusion criteria. Results: Cancer-associated fibroblasts (CAFs), M2 macrophages, and myeloid-derived suppressor cells (MDSCs) are significant in remodeling the TME to promote melanoma growth. Melanoma resistance to ICIs is complex and involves TME alterations, tumor intrinsic factors, and immune evasion. Key components of resistance include reduced CD8+ T cell infiltration, decreased host immune response, and immunosuppressive cytokines. Conclusions: Predictive biomarkers and specific models are the future of individualized melanoma management and show great promise in their approach to targeted therapy production. Tumor profiling can be utilized to help predict the efficacy of ICIs, and specific biomarkers predicting therapy responses are instrumental in moving towards personalized and more efficacious medicine. As more melanoma resistance emerges, alternative and combinatorial therapy based on knowledge of existing resistance mechanisms will be needed. Full article

Cutaneous melanoma is an aggressive cancer with an increasing incidence worldwide, highlighting the need for research into its pathogenesis. The tumor microenvironment (TME) plays a critical role in melanoma progression and consists of cellular components and an extracellular matrix (ECM) rich in cytokines and signaling molecules. The most abundant stromal cells within the TME are cancer-associated fibroblasts (CAFs), which remodel the ECM and modulate immune responses. Among immune cells, tumor-associated macrophages (TAMs) predominate, and their polarization toward the M2 phenotype supports tumor progression. Tumor-infiltrating lymphocytes (TILs) have diverse functions, including cytotoxic T-cells, helper T-cells that modulate immune response, B-cells forming tertiary lymphoid structures (TLS), and regulatory T-cells with immunosuppressive properties. Dendritic cells (DCs) also play a complex role in the TME. A notable subpopulation are mature regulatory dendritic cells (mregDCs), which contribute to immune evasion. All of these TME components may drive tumorigenesis. Advancements in melanoma treatment—including immunotherapy and targeted therapies—have significantly improved outcomes in advanced-stage disease. In parallel, emerging approaches targeting the tumor microenvironment and gut microbiome, as well as personalized strategies such as neoantigen vaccines and cell-based therapies, are under active investigation and may further enhance therapeutic efficacy in the near future. Full article

Gliomas, particularly IDH-wildtype ones, are associated with poor prognosis, yet their immunological landscape remains uncertain. We analyzed RNA sequencing data from 55 glioma patients, estimating immune infiltration with CIBERSORTx and immune cell states via Ecotyper. IDH-wildtype gliomas showed significantly higher immune cell infiltration (p = 0.002), notably of regulatory T cells (Tregs) and macrophages, and a greater proportion of exhausted T cells compared to IDH-mutant gliomas. Clustering based on immune profiles revealed two groups. Cluster A, enriched for IDH-wildtype cases, exhibited heightened immune infiltration but also marked immunosuppression. Cluster B, which included both IDH-wildtype and mutant cases, showed lower levels of immune infiltration. Tumor-infiltrating lymphocyte (TIL) cultured from IDH-wildtype tumors demonstrated limited expansion following anti-PD-1, a CSF1R inhibitor, or a STAT3 inhibitor treatment, without clear cluster-specific differences. Tumor-reactive TILs were mainly observed in cluster A. These findings highlight that IDH-wildtype gliomas have an immunosuppressive and heterogeneous microenvironment, potentially limiting responses to single-agent immunotherapies. A personalized, multi-targeted approach addressing multiple immunosuppressive mechanisms may be essential to improve immunotherapy outcomes in this aggressive glioma subgroup. Full article

Peptide vaccines possess several advantages over mRNA vaccines but are generally less effective at inducing antitumor immunity. The bottlenecks limiting peptide vaccine efficacy could be elucidated by tracking and comparing vaccine-induced T-lymphocytes in successful and unsuccessful cases. Here we have applied our recent database of neoantigen-specific T cell receptors (TCRs) to profile tumor-specific T cells following vaccination with a neoantigen peptide vaccine and to correlate this with the response. Mice were vaccinated prophylactically with p30 peptide encoding B16 melanoma neoantigen (K739N mutation in Kif18b gene). The B16F0 melanoma in the vaccinated mice was additionally treated by a CTLA-4 checkpoint blockade. T cells from the tumors, tumor-draining lymph nodes (tdLNs) and vaccine depots were isolated, phenotyped, sorted by subsets and sequenced for TCR repertoires. The vaccine induced the accumulation of tumor-specific CD4+ Th cells in the tdLNs, while in the tumors these cells were present and their frequencies were not changed by the vaccine. These cells also accumulated at the vaccine depots, where they were phenotypically skewed by the vaccine components; however, these effects were minor due to approximately 50-fold lower cell quantities compared to the tdLNs. Only some of the p30-specific Th cells showed tumoricidal activity, as revealed by the reverse correlation of their frequencies in the tdLNs with the tumor size. The CTLA-4 blockade did not affect the tumor growth or the frequencies of tumor-specific cells but did stimulate Th cell motility. Thus, we have shown that tumor-specific Th clones accumulate and/or expand in the tdLNs, which correlates with tumor suppression but only for some of these clones. Tumor infiltration by these clones is not correlated with the growth rate. Full article

Background/Objectives: Chimeric antigen receptor T-cell (CAR-T) therapy is a novel form of adoptive cellular immunotherapy that involves modifying autologous T cells to recognize and target tumor-associated antigens (TAAs) on malignant cells, independent of major histocompatibility complex (MHC) restriction. Although CAR-T therapy has shown remarkable success in treating hematologic malignancies, its efficacy in solid tumors remains limited, largely due to the lack of tumor-specific antigens and the complexity of the tumor microenvironment. This review aims to explore the rationale for continuing the development of adoptive cellular therapies in head and neck cancer (HNC), offering insights into the diagnostic and therapeutic challenges associated with this heterogeneous group of malignancies. Methods: We conducted a comprehensive literature review using the PubMed database to identify relevant studies on the application of CAR-T cell therapy in the management of HNC. Results: HNC presented numerous barriers to CAR-T cell infiltration, primarily due to the unique characteristics of its tumor microenvironment (TME). The TME in HNC is notably immunosuppressive, with a lymphocytic infiltrate predominantly composed of regulatory T cells (Tregs) and natural killer (NK) cells. These immune cells typically exhibit low expression of the CD16 receptor, which plays a crucial role in mediating antibody-dependent cellular cytotoxicity (ADCC), thereby limiting the effectiveness of CAR-T cell therapy. Conclusions: This comprehensive review suggests a potential clinical applicability of CAR-T therapy in HNC management. Full article

Head and neck squamous cell carcinoma (HNSCC) is a highly heterogeneous malignancy characterized by a complex tumor microenvironment (TME) that plays a critical role in disease progression and therapeutic resistance. Tumor-infiltrating immune cells, including T lymphocytes, macrophages, dendritic cells, and myeloid-derived suppressor cells, exhibit dual functions, either promoting or suppressing tumor growth depending on their phenotype and interactions within the TME. The presence of immune evasion mechanisms, such as the loss of human leukocyte antigen (HLA) expression, upregulation of immune checkpoint molecules, and metabolic reprogramming (hypoxia-induced glycolysis and lactate accumulation), further contributes to immune suppression and poor treatment responses. While immune checkpoint inhibitors (ICIs) have revolutionized the treatment of recurrent/metastatic HNSCC, response rates remain highly variable, underscoring the need for biomarker-driven patient selection and combinatorial therapeutic strategies. This review provides a comprehensive analysis of the role of immune cells in the TME of HNSCC, discusses the mechanisms underlying immune escape, and explores emerging immunotherapeutic and epigenetic-targeting approaches aimed at enhancing antitumor immune responses and improving clinical outcomes. Full article

Chimeric antigen receptor (CAR)-engineered immune cells, particularly CAR T lymphocytes and CAR natural killer (NK) cells, have revolutionized cancer immunotherapy. However, their therapeutic efficacy and safety can be influenced by the tumor microenvironment, particularly the presence of mesenchymal stem cells (MSCs). MSCs are immunomodulatory cells which can alter the function of tumor-infiltrated immune cells in both supportive and suppressive ways. Results obtained in recently conducted experimental studies demonstrate that MSCs modulate proliferation, cytotoxicity, cytokine production and anti-tumor activity in CAR-expressing immune cells in both a juxtacrine and a paracrine manner. While MSCs can enhance CAR cell viability and persistence through trophic support, they may also impair cytotoxic function and promote an immunosuppressive phenotype under certain conditions. Understanding the dualistic nature of MSCs in CAR-based immunotherapy for malignant diseases is critical for optimizing clinical outcomes. Additionally, MSCs may serve as vehicles for targeted delivery of immunomodulatory agents, and should be considered as active components in the design of next-generation CAR-based immunotherapies. Accordingly, in this review article we emphasize molecular and cellular mechanisms involved in MSC-dependent modulation of CAR-expressing immune cells, paving the way for more efficient CAR-based immunotherapy for malignant diseases. Full article

BAP31, a transmembrane protein in the endoplasmic reticulum, is known for its oncogenic properties, but its role in immunotherapy is not well understood. While BAP31’s involvement in liver, gastric, and cervical cancers has been documented, its role in pan-cancer immune regulation, particularly in breast cancer, remains unexplored. Using TCGA data, analysis via the Xiantao academic and GEPIA2 database showed that BAP31 upregulation correlates with advanced clinical stages and a poor prognosis. ROC analysis demonstrated BAP31’s high accuracy in distinguishing cancerous tissue from normal tissues. Additionally, BAP31 expression is associated with CNV, methylation, TMB, and MSI. In breast cancer, TIMER database analysis revealed that BAP31 expression is inversely correlated with the infiltration levels of myeloid-derived suppressor cells (MDSCs), macrophages, T lymphocytes, B lymphocytes, and neutrophils. Additionally, we investigated the relationship between BAP31 and the expression of major histocompatibility complex (MHC) molecules and chemokine receptors utilizing the TISIDB database. LinkedOmics analysis demonstrated associations between BAP31 and various immune-inflammatory pathways, while also indicating a negative correlation between BAP31 expression and four critical pathways: extracellular matrix receptor interaction, focal adhesion, JAK-STAT signaling, and TGF-β signaling. Furthermore, loss-of-function experiments employing shRNA-mediated knockdown of BAP31 resulted in a marked reduction in cell proliferation and an increase in apoptosis in breast cancer cells, thereby confirming its role in tumor promotion. These findings suggest that BAP31 may serve as a promising prognostic biomarker and a potential target for immunotherapy in breast cancer. Full article

UL16-binding protein 2 (ULBP2), a ligand for the activating receptor NKG2D, plays a dual role in tumor immunity, promoting immune activation or suppression, depending on the context. To investigate its impact on CD4⁺CD25⁺ T cell-targeted immunotherapies, we used a syngeneic CT26 colon cancer model engineered to express ULBP2 and compared tumor growth and tumor-infiltrating lymphocyte (TIL) profiles in control and ULBP2-expressing tumors treated with anti-CD4, anti-CD25, or anti-CTLA-4 antibodies. Tumor growth was uniformly assessed on day 21 post-transplantation, and TIL analysis was performed in groups with evaluable residual tumors. Anti-CD4 antibody significantly suppressed tumor growth in mock-transfected tumors, while no significant suppression was observed in ULBP2-expressing tumors. Anti-CD25 antibody had limited efficacy in mock tumors and tended to promote tumor growth in ULBP2-expressing tumors. Following these treatments, ULBP2 expression was associated with reduced NKG2D expression in CD8⁺ effector memory T cells, particularly PD-1^high subsets. In contrast, anti-CTLA-4 antibody treatment induced marked tumor regression irrespective of ULBP2 expression. These findings suggest that ULBP2–NKG2D signaling may contribute to altered CD8⁺ T cell phenotypes under T cell-modulatory conditions, potentially impacting the outcome of CD4⁺CD25⁺ T cell-targeted therapies and providing insights for optimizing immunotherapeutic strategies. Full article

Solid tumors pose significant therapeutic challenges due to their resistance to conventional treatments and the complexity of the tumor microenvironment. Cell-based immunotherapies offer a promising approach, enabling precise, personalized treatment through immune system modulation. This review explores several emerging cellular therapies for solid tumors, including tumor-infiltrating lymphocytes, T cell receptor-engineered T cells, CAR T cells, CAR natural killer cells, and macrophages. Tumor-infiltrating lymphocytes and their modified versions, T cell receptor-engineered T cells and CAR T cells, provide personalized immune responses, although their effectiveness can be limited by factors like variation in tumor antigens and the suppressive nature of the tumor environment. Natural killer cells engineered with chimeric receptors offer safer, non-major histocompatibility complex-restricted targeting, while modified macrophages exploit their natural ability to enter tumors and reshape the immune landscape. CAR-modified macrophages and macrophages conjugated with drugs are also considered as therapy for solid tumors. The review also examines the implications of autologous versus allogeneic cell sources. Autologous therapies ensure immunologic compatibility but are limited by scalability and manufacturing constraints. Allogeneic approaches offer “off-the-shelf” potential but require gene editing to avoid immune rejection. Integrating synthetic biology, gene editing, and combinatorial strategies will be essential to enhance efficacy and expand the clinical utility of cellular immunotherapies for solid tumors. Full article

The incidence of melanoma is increasing globally, even in the wake of increased risk factor awareness and a growing body of advanced therapeutic options. It is apparent that the treatment of melanoma will remain a topic of worry in areas of the world under high ultraviolet exposure and areas that harbor individuals with fair skin phenotypes. In the wake of such concern, the potential of immunotherapy and various targeted therapeutics to treat late-stage melanoma is increasing. In addition to the growing arsenal of PD-1 and PD-L1 immune checkpoint inhibitors, other targeted therapies are being developed and tested to treat melanoma. BRAF/MEK inhibitors target a key proliferative pathway in melanoma, offering clinical benefit but limited durability. Next-generation agents and triplet therapy with immunotherapy aim to improve outcomes. Androgen receptor signaling may also modulate responses to both targeted and immune-based treatments. Bispecific T cell engagers assist with guiding the body’s own T cells to tumors where they release toxins that kill the tumor cell. Personalized neoantigen vaccines target tumor-specific antigens by sequencing a patient’s cancerous cells to create tailored vaccines that elicit a strong and specific immune response. Tumor-infiltrating lymphocytes are autologous lymphocytes reinfused back into the host that are showing efficacy in the treatment of advanced melanoma. Together, these therapies are advancing the arsenal of chemotherapeutic options that can be used to inhibit the progression of melanoma. Full article

Background/Objectives: Nucleic acid-based anticancer vaccines are becoming a very active field in the fight against cancer. Here, our goal was to generate an oral DNA vaccine targeting the angiogenic peptide, proadrenomedullin N-terminal 20 peptide (PAMP). Methods: An expression plasmid (PcPAMP) was generated by fusing the tetanus toxin epitopes P2 and P30 to the mouse PAMP sequence to counteract self-tolerance, and the empty plasmid was used as a negative control (PcNeg). The plasmids were introduced into Salmonella typhimurium bacteria that were then transformed into bacterial ghosts. C57BL/6J mice were orally immunized with the ghosts five times at 2-week intervals. Then, B16-F10 melanoma cells were injected into the tail vein to generate lung metastases. Furthermore, naïve CD4⁺ T cells were exposed to PAMP, and their secretome was analyzed by proximity extension assays. Results: Significant levels of anti-PAMP immunoglobulins were detected in the blood of PcPAMP-vaccinated mice and their levels of spleen CD8⁺ T cells were significantly higher than in those treated with PcNeg, indicating that self-tolerance was effectively broken. Although the number and size of lung metastases was similar between both experimental groups, there was a significant reduction in intratumoral angiogenesis and in cancer cell proliferation index in the PcPAMP group. Furthermore, these animals showed an intense infiltration of lymphocytes, including regulatory T cells, and M2-like macrophages into the metastases, that was not evident in the PcNeg group. In addition, PAMP induced upregulation of IL1β, IL6, IL7, IL12, IL27, TNFα, and FGF21, and downregulation of IL16 in naïve CD4⁺ T cells. Conclusions: Although the vaccine was not effective in reducing tumor growth, new proliferative and immune functions have been described for PAMP. These new functions include induction of melanoma proliferation and modulation of lymphocyte and macrophage tumor infiltration dynamics. Full article