Search Results (50)

Background: Melanoma is one of the most aggressive types of skin cancer. Its diagnosis appears to be challenging due to morphological similarities to benign melanocytic lesions. Even though histopathological evaluation is the diagnostic gold standard, immunohistochemistry (IHC) proves to be useful in challenging cases. Preferentially Expressed Antigen in Melanoma (PRAME) has emerged as a promising diagnostic, prognostic, and therapeutic marker in melanoma. Methods: This review critically examines the role of PRAME across clinical domains. It presents an evaluation of PRAME’s diagnostic utility in differentiating melanomas from benign nevi, its prognostic significance across melanoma subtypes, and therapeutic applications in emerging immunotherapy strategies. An extensive analysis of the current literature was conducted, with a focus on PRAME expression patterns in melanocytic lesions and various malignancies, along with its integration into IHC protocols and investigational therapies. Results: PRAME demonstrates high specificity and sensitivity in distinguishing melanoma from benign melanocytic proliferations, particularly in challenging subtypes such as acral, mucosal, and spitzoid lesions. Its overexpression correlates with poor prognosis in numerous malignancies. Therapeutically, PRAME’s HLA class I presentation enables T-cell-based targeting. Early-phase trials show promising results using PRAME-directed TCR therapies and bispecific ImmTAC agents. However, immune evasion mechanisms (i.e., heterogeneous antigen expression, immune suppression in the tumor microenvironment, and HLA downregulation) pose significant challenges to therapy. Conclusions: PRAME is a valuable biomarker for melanoma diagnosis and a promising target for immunotherapy. Its selective expression in malignancies supports its clinical utility in diagnostic precision, prognostic assessment, and precision oncology. Ongoing research aimed at overcoming immunological barriers will be essential for optimizing PRAME-directed therapies and establishing their place in the personalized management of melanoma. Full article

Tumor immunogenicity depends on the ability of peptides to form stable and specific interactions with both HLA molecules and T-cell receptors (TCRs). While HLA binding is essential, not all HLA-binding peptides elicit T-cell responses. This study investigates the molecular features distinguishing immunogenic T-cell epitopes from non-immunogenic HLA binders. Two datasets of nonamer peptides—38 T-cell epitopes and 144 non-epitopes—were compiled and analyzed using sequence logo models and molecular dynamics (MD) simulations of TCR–peptide–HLA complexes. A comparative logo analysis revealed strong amino acid preferences at central positions (p4–p8) in T-cell epitopes and absences in non-epitopes. A representative epitope–non-epitope pair was selected for structural modeling and 100 ns MD simulations. The T-cell epitope formed a more stable complex with the TCR and exhibited greater flexibility, supporting an induced-fit recognition mechanism. It also established a broader and longer-lasting network of hydrogen bonds and π interactions across the residues at positions p4–p8. In contrast, the non-epitope engaged TCR at only two positions. These findings highlight the critical role of the peptide’s central region in TCR engagement and provide structural insights useful for neoantigen prediction, vaccine design, and TCR-based immunotherapies. Full article

Cancer is a major global health issue, with rising incidence rates highlighting the urgent need for more effective treatments. Despite advances in cancer therapy, challenges such as adverse effects and limitations of existing treatments remain. Immunotherapy, which harnesses the body’s immune system to target cancer cells, offers promising solutions. Gamma delta (γδ) T cells are noteworthy due to their potent ability to kill various cancer cells without needing conventional antigen presentation. Recent studies have focused on the role of γδ T cells in α-galactosylceramide (α-GalCer)-mediated immunity, opening new possibilities for cancer immunotherapy. We engineered humanized T cell receptor (HuTCR)-T1 γδ mice by replacing mouse sequences with human counterparts. This study investigates the cytotoxic activity of humanized γδ T cells against several human cancer cell lines (A431, HT-29, K562, and Daudi) in vitro, aiming to elucidate mechanisms underlying their anticancer efficacy. Human cancer cells were co-cultured with humanized γδ T cells, with and without α-GalCer, for 24 h. The humanized γδ T cells showed enhanced cytotoxicity across all tested cancer cell lines compared to wild-type γδ T cells. Additionally, γδ T cells from HuTCR-T1 mice exhibited higher levels of anticancer cytokines (IFN-γ, TNF-α, and IL-17) and Granzyme B, indicating their potential as potent mediators of anticancer immune responses. Blocking γδ T cells’ cytotoxicity confirmed their γδ-mediated function. These findings represent a significant step in preclinical development of γδ T cell-based cancer immunotherapies, providing insights into their mechanisms of action, optimization of therapeutic strategies, and identification of predictive biomarkers for clinical application. Full article

CD8+ T lymphocytes (CTLs) act as serial killers of infected or malignant cells by releasing large amounts of interferon-gamma (IFNγ) and granzymes. Although IFNγ is a pleiotropic cytokine with diverse immunomodulatory functions, its precise spatiotemporal regulation and role in CTL-mediated cytotoxicity remain incompletely understood. Using wild-type and granzyme B-mTFP knock-in mice, we employed a combination of in vitro approaches, including T cell isolation and culture, plate-bound anti-CD3e stimulation, degranulation assays, flow cytometry, immunofluorescence, and structured illumination microscopy, to investigate IFNγ dynamics in CTLs. IFNγ expression in CTLs was rapid, transient, and strictly dependent on T cell receptor (TCR) activation. We identified two functionally distinct IFNγ-producing subsets: IFNγ^high (IFNγ^hi) and IFNγ^low (IFNγ^lo) CTLs. IFNγ^hi CTLs exhibited an effector/effector memory phenotype, significantly elevated CD107a surface expression (a marker of lytic granule exocytosis), and higher colocalization with cis-Golgi and granzyme B compared to IFNγ^lo CTLs. Furthermore, CRTAM, an early activation marker, correlated with IFNγ expression in naive CTLs. Our findings establish a link between elevated IFNγ production and enhanced CTL cytotoxicity, implicating CRTAM as a potential regulator of early CTL activation and IFNγ induction. These insights provide a foundation for optimizing T cell-based immunotherapies against infections and cancers. Full article

Uveal melanoma (UM), the most common primary intraocular malignancy in adults, poses a unique clinical challenge due to its high propensity for liver metastasis and poor responsiveness to conventional therapies. Despite the expanding landscape of immunotherapy in oncology, progress in managing metastatic uveal melanoma (mUM) remains limited, and no universally accepted standard of care has been established. In this review, we examine the current state and evolving strategies in immunotherapy for mUM, focusing on immune checkpoint inhibitors (ICIs), T cell receptor (TCR)-engineered therapies, and tumor-targeted vaccines. We also present a meta-analytical comparison of clinical outcomes between ICI monotherapy and combination regimens, alongside the recently FDA-approved T cell engager tebentafusp. Our analysis indicates that the triple combination of Ipilimumab, anti-PD-1 agents, and tebentafusp significantly enhances objective response rates, disease control rates, 1-year overall survival rates, and median overall survival (mOS) compared to ICI monotherapy alone. However, this enhanced efficacy is accompanied by increased toxicity due to broader immune activation. In contrast, tebentafusp offers superior tumor specificity and a more favorable safety profile in HLA-A*02:01-positive patients, positioning it as a preferred therapeutic option for this genetically defined subset of UM. Additionally, early-phase studies involving dendritic cell-based immunotherapies and peptide vaccines has shown encouraging signs of tumor-specific immune activation, along with improved tolerability. Collectively, this review underscores the urgent need for more precise and effective immunotherapeutic approaches tailored to the unique biology of mUM. Full article

Background/Objectives: The physiological activation of cytotoxic CD8^pos T cells (CTLs) relies on the engagement of the TCR/CD3 complex with cognate peptide-HLA class I (pHLA-I) on target cells, triggering cell lysis with appropriate cytokine release and minimized off-target toxicity. In contrast, current immunotherapies for CD19-expressing hematological malignancies, such as chimeric antigen receptor (CAR) T cells and bispecific T cell engagers (BiTEs), bypass TCR/pHLA interactions, resulting in CTL hyperactivation and excessive cytokine release, which frequently cause severe immune-related adverse events (irAEs). Thus, there is a pressing need for T cell-based therapies that preserve physiological activation while maintaining antitumor efficacy. Methods: To address this, we developed CD19-ReTARG^TPR, a novel fusion protein consisting of the immunodominant cytomegalovirus (CMV) pp65-derived peptide TPRVTGGAM (TPR) covalently presented by a soluble HLA-B*07:02/β2-microglobulin complex fused to a high-affinity CD19-targeting Fab antibody fragment. The treatment of CD19-expressing cancer cells with CD19-ReTARG^TPR makes them recognizable for pre-existing anti-CMV_pp65 CTLs via physiological TCR-pHLA engagement. Results: Our preclinical data demonstrate that CD19-ReTARG^TPR efficiently redirects anti-CMV CTLs to eliminate CD19-expressing cancer cells, including both established cell lines and primary chronic lymphocytic leukemia (CLL) cells. Unlike CD19-directed CAR T cells or the CD19/CD3 BiTE blinatumomab, CD19-ReTARG^TPR mediated robust cytotoxic activity without triggering supraphysiological cytokine release. Importantly, this approach retained efficacy even against cancer cells with low CD19 expression. Conclusions: In summary, we provide a robust proof-of-concept study and show that CD19-ReTARG^TPR offers a promising alternative strategy for T cell redirection, enabling the selective and effective killing of CD19-expressing malignancies while minimizing cytokine-driven toxicities through physiological CTL activation pathways. Full article

Ruxolitinib, a clinically approved JAK1/2 inhibitor used in the treatment of hematologic malignancies and inflammatory conditions, has been shown to interfere with the function of cytotoxic T lymphocytes (CTLs). Previous studies supported the involvement of the multidrug resistance transporter P-glycoprotein (Pgp/ABCB1) in CTL biology; however, the nature of its regulation remains unclear. To address this, we investigated the impact of ruxolitinib on Pgp expression and function in human CD8⁺ T cells. We demonstrate that CD8⁺ T lymphocytes express Pgp dynamically at both the mRNA and protein levels across naïve, short-term, and long-term activation states. Ruxolitinib increased the calcein accumulation in human Pgp-overexpressing NIH-3T3 cells and in CTLs and directly modulated Pgp function by increasing its basal ATPase activity in a concentration-dependent manner (10–100 μM), similar to the effect of the known Pgp substrate/modulator verapamil. Although measurable ATPase stimulation and transport inhibition were observed at supratherapeutic concentrations of ruxolitinib, its Pgp-mediated efflux may also occur at therapeutically relevant concentrations. In contrast, at therapeutically relevant plasma concentrations (1–3 μM), ruxolitinib significantly stabilized the mRNA expression of Pgp during early T-cell receptor (TCR) activation and inhibited the TCR-induced upregulation of Pgp, CD8, and PD-1 surface markers, suggesting its interference with activation-associated differentiation. At these same concentrations, ruxolitinib also impaired CCL19-directed transmigration of CTLs across human umbilical vein endothelial cell (HUVEC) monolayers, indicating disruption of lymphoid homing cues. Collectively, these findings demonstrate that ruxolitinib modulates Pgp at both the transcriptional and functional levels, with distinct concentration dependence. The ability of ruxolitinib to alter CTL activation and migration at clinically relevant plasma concentrations highlights the need for careful evaluation of JAK inhibitor–mediated immunomodulation and its implications for vaccination, transplantation, and T cell-based immunotherapies. Full article

Chimeric antigen receptor (CAR)-T and T-cell receptor (TCR)-engineered T-cell (TCR-T) therapies have revolutionized the treatment of hematological malignancies; however, their application to solid tumors remains a formidable challenge. The immunosuppressive tumor microenvironment, antigen heterogeneity, and manufacturing complexity limit the clinical efficacy and scalability of these treatment modalities. This review provides a comprehensive analysis of the current clinical development strategies for CAR-T and TCR-T cell therapies for solid tumors. Herein, we discuss recent breakthroughs and highlight the potential of TCR-T cell therapy. Furthermore, innovative approaches for enhancing CAR-T cell function in solid tumors (e.g., in vivo engineering; induced pluripotent stem cell-derived allogeneic CAR-T cells; armored CAR constructs; dual-antigen targeting; and combination regimens with checkpoint inhibitors, chemotherapy, radiotherapy, and oncolytic viruses) are explored. We also present trends in global patent activity, revealing a marked acceleration in CAR-T- and TCR-T-related innovations, with the United States and China leading with respect to application volumes. This field is increasingly characterized by multidisciplinary collaborations between academia and industry, driving the development of next-generation platforms, including messenger RNA-based and off-the-shelf cell therapies. Although no CAR-T product has been approved for solid tumors, these findings underscore the accelerating momentum and translational promise of adoptive cell therapies. Addressing the unique biological and logistical challenges of solid tumors is essential for realizing the full potential of these transformative immunotherapies. Full article

The incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) has increased substantially over the past three decades, and since 2017, it has been recognized in the AJCC staging system as distinct from its HPV-negative counterpart. The underlying mechanisms of HPV-associated carcinogenesis, tumor microenvironment, and host immune response represent opportunities for therapeutic development. While anti-PD-1 immunotherapy is now part of standard treatment for recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) in general, there are no established immunotherapeutic strategies specifically for HPV-related HNSCC. In this context, multiple emerging approaches are being actively studied—among these are therapeutic vaccines with or without anti-PD-(L)1 adjuvants, peptide–HLA-based immunotherapeutic platforms, and adoptive cell therapies including tumor-infiltrating lymphocytes (TILs), T-cell receptor (TCR) therapy, and chimeric antigen receptor (CAR) T-cell therapy. Beyond further maturation of these novel immunotherapeutic strategies, additional work is needed to delineate the optimal disease state of application (localized versus recurrent/metastatic), as well as in the development of small molecule inhibitors targeting HPV-specific mechanisms of viral oncogenesis. Full article

The rapid increase in colorectal cancer (CRC) cases recently has highlighted the need to use predictive biomarkers to guide therapeutic approaches. Current studies have focused on the tumor-infiltrating lymphocytes present in the tumor microenvironment (TME), in which cytotoxic T cell activation and the amount are associated with CRC patient prognosis. The T cell receptor (TCR) is essential for antigen recognition and T cell identification, playing a central role in cancer immunotherapy. The T cell status reflects TCR diversity or clonality, known as the TCR repertoire. Accordingly, analyzing the TCR repertoire dynamics may help predict the immunological circumstances of the TME in a timely way. In this review, we summarize the TCR repertoire-related knowledge, including its potential use as predictive biomarkers in CRC. The intratumoral TCR repertoire is restricted in CRC patients compared with healthy individuals, as well as in peripheral blood. Patients with deficient mismatch repair display more restriction than those with proficient mismatch repair. Importantly, a higher TCR diversity before treatment and a decrease following treatment may indicate a good response and a better clinical outcome in CRC patients. The future use of TCR repertoire sequencing technology combined with artificial intelligence-based analysis is a potential strategy for CRC therapeutic decision making. Full article

We investigated the design and characterization of a Lab-On-a-Chip (LoC) cell detection system primarily designed to support immunotherapy in cancer treatment. Immunotherapy uses Chimeric Antigen Receptors (CARs) and T Cell Receptors (TCRs) to fight cancer, engineering the response of the immune system. In recent years, it has emerged as a promising strategy for personalized cancer treatment. However, it requires bioreactor-based cell culture expansion and manual quality control (QC) of the modified cells, which is time-consuming, labour-intensive, and prone to errors. The miniaturized LoC device for automated QC demonstrated here is simple, has a low cost, and is reliable. Its final target is to become one of the building blocks of an LoC for immunotherapy, which would take the place of present labs and manual procedures to the benefit of throughput and affordability. The core of the system is a commercial, on-chip-integrated capacitive sensor managed by a microcontroller capable of sensing cells as accurately measured charge variations. The hardware is based on standardized components, which makes it suitable for mass manufacturing. Moreover, unlike in other cell detection solutions, no external AC source is required. The device has been characterized with a cell line model selectively labelled with gold nanoparticles to simulate its future use in bioreactors in which labelling can apply to successfully engineered CAR-T-cells. Experiments were run both in the air—free drop with no microfluidics—and in the channel, where the fluid volume was considerably lower than in the drop. The device showed good sensitivity even with a low number of cells—around 120, compared with the 10⁷ to 10⁸ needed per kilogram of body weight—which is desirable for a good outcome of the expansion process. Since cell detection is needed in several contexts other than immunotherapy, the usefulness of this LoC goes potentially beyond the scope considered here. Full article

Cholangiocarcinoma (CCA) is a rare and aggressive malignancy originating from the bile ducts, with poor prognosis and limited treatment options. Traditional therapies, such as surgery, chemotherapy, and radiation, have shown limited efficacy, especially in advanced cases. Recent advancements in immunotherapy, particularly T cell-based therapies like chimeric antigen receptor T (CAR T) cells, tumor-infiltrating lymphocytes (TILs), and T cell receptor (TCR)-based therapies, have opened new avenues for improving outcomes in CCA. This review provides a comprehensive overview of the current state of T cell therapies for CCA, focusing on CAR T cell therapy. It highlights key challenges, including the complex tumor microenvironment and immune evasion mechanisms, and the progress made in preclinical and clinical trials. The review also discusses ongoing clinical trials targeting specific CCA antigens, such as MUC1, EGFR, and CD133, and the evolving role of precision immunotherapy in enhancing treatment outcomes. Despite significant progress, further research is needed to optimize these therapies for solid tumors like CCA. By summarizing the most recent clinical results and future directions, this review underscores the promising potential of T cell therapies in revolutionizing CCA treatment. Full article

Neoantigens, presented as peptides on the surfaces of cancer cells, have recently been proposed as optimal targets for immunotherapy in clinical practice. The promising outcomes of neoantigen-based cancer vaccines have inspired enthusiasm for their broader clinical applications. However, the individualized tumor-specific antigens (TSA) entail considerable costs and time due to the variable immunogenicity and response rates of these neoantigens-based vaccines, influenced by factors such as neoantigen response, vaccine types, and combination therapy. Given the crucial role of neoantigen efficacy, a number of bioinformatics algorithms and pipelines have been developed to improve the accuracy rate of prediction through considering a series of factors involving in HLA-peptide-TCR complex formation, including peptide presentation, HLA-peptide affinity, and TCR recognition. On the other hand, shared neoantigens, originating from driver mutations at hot mutation spots (e.g., KRAS^G12D), offer a promising and ideal target for the development of therapeutic cancer vaccines. A series of clinical practices have established the efficacy of these vaccines in patients with distinct HLA haplotypes. Moreover, increasing evidence demonstrated that a combination of tumor associated antigens (TAAs) and neoantigens can also improve the prognosis, thus expand the repertoire of shared neoantigens for cancer vaccines. In this review, we provide an overview of the complex process involved in identifying personalized neoantigens, their clinical applications, advances in vaccine technology, and explore the therapeutic potential of shared neoantigen strategies. Full article

Molecular biology studies of uveal melanoma have resulted in the development of novel immunotherapy approaches including tebentafusp—a T cell–redirecting bispecific fusion protein. More biomarkers are currently being studied. As a result, combined immunotherapy is being developed as well as immunotherapy with bifunctional checkpoint inhibitory T cell engagers and natural killer cells. Current trials cover tumor-infiltrating lymphocytes (TIL), vaccination with IKKb-matured dendritic cells, or autologous dendritic cells loaded with autologous tumor RNA. Another potential approach to treat UM could be based on T cell receptor engineering rather than antibody modification. Immune-mobilizing monoclonal T cell receptors (TCR) against cancer, called ImmTAC TM molecules, represent such an approach. Moreover, nanomedicine, especially miRNA approaches, are promising for future trials. Finally, theranostic radiopharmaceuticals enabling diagnosis and therapy with the same molecule bring hope to this research. Full article

GvHD still remains, despite the continuous improvement of transplantation platforms, a fearful complication of transplantation from allogeneic donors. Being able to separate GvHD from GvL represents the greatest challenge in the allogeneic transplant setting. This may be possible through continuous improvement of cell therapy techniques. In this review, current cell therapies are taken into consideration, which are based on the use of TCR alpha/beta depletion, CD45RA depletion, T regulatory cell enrichment, NK-cell-based immunotherapies, and suicide gene therapies in order to prevent GvHD and maximally amplify the GvL effect in the setting of haploidentical transplantation. Full article