Factors contributing to the potency of CD8+ T cells

Enzyme-Instructed Photoactivatable Supramolecular Antigens on Cancer Cell Membranes for Precision-Controlled T-Cell-Based Cancer Immunotherapy

Cancer immunotherapies based on cytotoxic CD8+ T lymphocytes (CTLs) are highly promising for cancer treatment. The specific interaction between T-cell receptors and peptide-MHC-I complexes (pMHC-I) on cancer cell membranes critically determines their therapeutic outcomes. However, the lack of appropriate endogenous antigens for MHC-I presentation disables tumor recognition by CTLs. By devising three antigen-loaded self-assembling peptides of pY-K(Ag)-ERGD, pY-K(Ag)-E, and Y-K(Ag)-ERGD to noncovalently generate light-activatable supramolecular antigens at tumor sites in different manners, we report pY-K(Ag)-ERGD as a promising candidate to endow tumor cells with pMHC-I targets on demand. Specifically, pY-K(Ag)-ERGD first generates low-antigenic supramolecular antigens on cancer cell membranes, and a successive light pulse allows antigen payloads to efficiently release from the supramolecular scaffold, directly producing antigenic pMHC-I. Intravenous administration of pY-K(Ag)-ERGD enables light-controlled tumor inhibition when combined with adoptively transferred antigen-specific CTLs. Our strategy is feasible for broadening tumor antigen repertoires for T-cell immunotherapies and advancing precision-controlled T-cell immunotherapies.

Immunocytes interact directly with cancer cells in the tumor microenvironment: one coin with two sides and future perspectives

The tumor microenvironment is closely linked to the initiation, promotion, and progression of solid tumors. Among its constitutions, immunologic cells emerge as critical players, facilitating immune evasion and tumor progression. Apart from their indirect impact on anti-tumor immunity, immunocytes directly influence neoplastic cells, either bolstering or impeding tumor advancement. However, current therapeutic modalities aimed at alleviating immunosuppression from regulatory cells on effector immune cell populations may not consistently yield satisfactory results in various solid tumors, such as breast carcinoma, colorectal cancer, etc. Therefore, this review outlines and summarizes the direct, dualistic effects of immunocytes such as T cells, innate lymphoid cells, B cells, eosinophils, and tumor-associated macrophages on tumor cells within the tumor microenvironment. The review also delves into the underlying mechanisms involved and presents the outcomes of clinical trials based on these direct effects, aiming to propose innovative and efficacious therapeutic strategies for addressing solid tumors.

PRKCSH serves as a potential immunological and prognostic biomarker in pan-cancer

Protein kinase C substrate 80K-H (PRKCSH) plays a crucial role in the protein N-terminal glycosylation process, with emerging evidence implicating its involvement in tumorigenesis. To comprehensively assess PRKCSH's significance across cancers, we conducted a pan-cancer analysis using data from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Cancer Cell Line Encyclopedia (CCLE). We assessed aberrant PRKCSH mRNA and protein expression, examined its prognostic implications, and identified correlations with clinical features, tumor mutational burden (TMB), microsatellite instability (MSI), and tumor immunity across cancer types. We explored PRKCSH gene alterations, DNA methylation, and their impact on patient prognosis. Gene Set Enrichment Analysis (GSEA) and single-cell analysis revealed potential biological roles. Additionally, we investigated drug susceptibility and conducted Connectivity Map (Cmap) analysis. Key findings revealed that PRKCSH exhibited overexpression in most tumors, with a significant association with poor overall survival (OS) in six cancer types. Notably, PRKCSH expression demonstrated variations across disease stages, primarily increasing in advanced stages among eleven tumor types. Moreover, PRKCSH exhibited significant correlations with TMB in five cancer categories, MSI in eight, and displayed associations with immune cell populations in pan-cancer analysis. Genetic variations in PRKCSH were identified across 26 tumor types, suggesting favorable disease-free survival. Furthermore, PRKCSH methylation displayed a significant negative correlation with its expression in 27 tumor types, with a marked decrease compared to normal tissues in ten tumors. Cmap predicted 24 potential therapeutic small molecules in over four cancer types. This study highlights that PRKCSH, as a potential oncogene, may be a promising prognostic marker and therapeutic target of immunotherapy for a range of malignancies.

Targeting MHC-I molecules for cancer: function, mechanism, and therapeutic prospects

The molecules of Major histocompatibility class I (MHC-I) load peptides and present them on the cell surface, which provided the immune system with the signal to detect and eliminate the infected or cancerous cells. In the context of cancer, owing to the crucial immune-regulatory roles played by MHC-I molecules, the abnormal modulation of MHC-I expression and function could be hijacked by tumor cells to escape the immune surveillance and attack, thereby promoting tumoral progression and impairing the efficacy of cancer immunotherapy. Here we reviewed and discussed the recent studies and discoveries related to the MHC-I molecules and their multidirectional functions in the development of cancer, mainly focusing on the interactions between MHC-I and the multiple participators in the tumor microenvironment and highlighting the significance of targeting MHC-I for optimizing the efficacy of cancer immunotherapy and a deeper understanding of the dynamic nature and functioning mechanism of MHC-I in cancer.