Dendritic cell vaccine trials in gliomas: Untangling the lines

Glioblastoma microenvironment-from biology to therapy

Glioblastoma (GBM) is the most aggressive primary brain cancer. These tumors exhibit high intertumoral and intratumoral heterogeneity in neoplastic and nonneoplastic compartments, low lymphocyte infiltration, and high abundance of myeloid subsets that together create a highly protumorigenic immunosuppressive microenvironment. Moreover, heterogeneous GBM cells infiltrate adjacent brain tissue, remodeling the neural microenvironment to foster tumor electrochemical coupling with neurons and metabolic coupling with nonneoplastic astrocytes, thereby driving growth. Here, we review heterogeneity in the GBM microenvironment and its role in low-to-high-grade glioma transition, concluding with a discussion of the challenges of therapeutically targeting the tumor microenvironment and outlining future research opportunities.

A systematic review of immunotherapy in high-grade glioma: learning from the past to shape future perspectives

High-grade gliomas (HGGs) constitute the most common malignant primary brain tumor with a poor prognosis despite the standard multimodal therapy. In recent years, immunotherapy has changed the prognosis of many cancers, increasing the hope for HGG therapy. We conducted a comprehensive search on PubMed, Scopus, Embase, and Web of Science databases to include relevant studies. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Fifty-two papers were finally included (44 phase II and eight phase III clinical trials) and further divided into four different subgroups: 14 peptide vaccine trials, 15 dendritic cell vaccination (DCV) trials, six immune checkpoint inhibitor (ICI) trials, and 17 miscellaneous group trials that included both "active" and "passive" immunotherapies. In the last decade, immunotherapy created great hope to increase the survival of patients affected by HGGs; however, it has yielded mostly dismal results in the setting of phase III clinical trials. An in-depth analysis of these clinical results provides clues about common patterns that have led to failures at the clinical level and helps shape the perspective for the next generation of immunotherapies in neuro-oncology.

Combinational delivery of TLR4 and TLR7/8 agonist enhanced the therapeutic efficacy of immune checkpoint inhibitors to colon tumor

Immunotherapy is regarded as a potent cancer treatment, with DC vaccines playing a crucial role. Although clinical trials have demonstrated the safety and efficacy of DC vaccines, loading antigens in vitro is challenging, and their therapeutic effects remain unpredictable. Moreover, the diverse subtypes and maturity states of DCs in the body could induce both immune responses and immune tolerance, potentially affecting the vaccine's efficacy. Hence, the optimization of DC vaccines remains imperative. Our study discovered a new therapeutic strategy by using CT26 and MC38 mouse colon cancer models, as well as LLC mouse lung cancer models. The strategy involved the synergistic activation of DCs through intertumoral administration of TLR4 agonist high-mobility group nucleosome binding protein 1 (HMGN1) and TLR7/8 agonist (R848/resiquimod), combined with intraperitoneal administration of TNFR2 immunosuppressant antibody. The experimental results indicated that the combined use of HMGN1, R848, and α-TNFR2 had no effect on LLC cold tumors. However, it was effective in eradicating CT26 and MC38 colon cancer and inducing long-term immune memory. The combination of these three drugs altered the TME and promoted an increase in anti-tumor immune components. This may provide a promising new treatment strategy for colon cancer.

T Cell Features in Glioblastoma May Guide Therapeutic Strategies to Overcome Microenvironment Immunosuppression

Glioblastoma (GBM) is the most aggressive and lethal primary brain tumor, bearing a survival estimate below 10% at five years, despite standard chemoradiation treatment. At recurrence, systemic treatment options are limited and the standard of care is not well defined, with inclusion in clinical trials being highly encouraged. So far, the use of immunotherapeutic strategies in GBM has not proved to significantly improve patients' prognosis in the treatment of newly diagnosed GBM, nor in the recurrent setting. Probably this has to do with the unique immune environment of the central nervous system, which harbors several immunosuppressive/pro-tumorigenic factors, both soluble (e.g., TGF-β, IL-10, STAT3, prostaglandin E2, and VEGF) and cellular (e.g., Tregs, M2 phenotype TAMs, and MDSC). Here we review the immune composition of the GBMs microenvironment, specifically focusing on the phenotype and function of the T cell compartment. Moreover, we give hints on the therapeutic strategies, such as immune checkpoint blockade, vaccinations, and adoptive cell therapy, that, interacting with tumor-infiltrating lymphocytes, might both target in different ways the tumor microenvironment and potentiate the activity of standard therapies. The path to be followed in advancing clinical research on immunotherapy for GBM treatment relies on a twofold strategy: testing combinatorial treatments, aiming to restore active immune anti-tumor responses, tackling immunosuppression, and additionally, designing more phase 0 and window opportunity trials with solid translational analyses to gain deeper insight into the on-treatment shaping of the GBM microenvironment.

Editorial on "Cell Therapy, Bispecific Antibodies and Other Immunotherapies against Cancer"

This Special Issue in Cancers, "Cell Therapy, Bispecific Antibodies and other Immunotherapies Against Cancer", includes interesting reports and reviews on cell therapies and bispecific antibodies [...].

Development of an MCL-1-related prognostic signature and inhibitors screening for glioblastoma

Introduction: The effect of the conventional treatment methods of glioblastoma (GBM) is poor and the prognosis of patients is poor. The expression of MCL-1 in GBM is significantly increased, which shows a high application value in targeted therapy. In this study, we predicted the prognosis of glioblastoma patients, and therefore constructed MCL-1 related prognostic signature (MPS) and the development of MCL-1 small molecule inhibitors. Methods: In this study, RNA-seq and clinical data of 168 GBM samples were obtained from the TCGA website, and immunological analysis, differential gene expression analysis and functional enrichment analysis were performed. Subsequently, MCL-1-associated prognostic signature (MPS) was constructed and validated by LASSO Cox analysis, and a nomogram was constructed to predict the prognosis of patients. Finally, the 17931 small molecules downloaded from the ZINC15 database were screened by LibDock, ADME, TOPKAT and CDOCKER modules and molecular dynamics simulation in Discovery Studio2019 software, and two safer and more effective small molecule inhibitors were finally selected. Results: Immunological analysis showed immunosuppression in the MCL1_H group, and treatment with immune checkpoint inhibitors had a positive effect. Differential expression gene analysis identified 449 differentially expressed genes. Build and validate MPS using LASSO Cox analysis. Use the TSHR HIST3H2A, ARGE OSMR, ARHGEF25 build risk score, proved that low risk group of patients prognosis is better. Univariate and multivariate analysis proved that risk could be used as an independent predictor of patient prognosis. Construct a nomogram to predict the survival probability of patients at 1,2,3 years. Using a series of computer-aided techniques, two more reasonable lead compounds ZINC000013374322 and ZINC000001090002 were virtually selected. These compounds have potential inhibitory effects on MCL-1 and provide a basis for the design and further development of MCL-1 specific small molecule inhibitors. Discussion: This study analyzed the effect of MCL-1 on the prognosis of glioblastoma patients from the perspective of immunology, constructed a new prognostic model to evaluate the survival rate of patients, and further screened 2 MCL-1 small molecule inhibitors, which provides new ideas for the treatment and prognosis of glioblastoma.