Pan-cancer analysis for the prognostic and immunological role of CD47: interact with TNFRSF9 inducing CD8 + T cell exhaustion.

PURPOSE: The research endeavors to explore the implications of CD47 in cancer immunotherapy effectiveness. Specifically, there is a gap in comprehending the influence of CD47 on the tumor immune microenvironment, particularly in relation to CD8 + T cells. Our study aims to elucidate the prognostic and immunological relevance of CD47 to enhance insights into its prospective utilities in immunotherapeutic interventions. METHODS: Differential gene expression analysis, prognosis assessment, immunological infiltration evaluation, pathway enrichment analysis, and correlation investigation were performed utilizing a combination of R packages, computational algorithms, diverse datasets, and patient cohorts. Validation of the concept was achieved through the utilization of single-cell sequencing technology. RESULTS: CD47 demonstrated ubiquitous expression across various cancer types and was notably associated with unfavorable prognostic outcomes in pan-cancer assessments. Immunological investigations unveiled a robust correlation between CD47 expression and T-cell infiltration rather than T-cell exclusion across multiple cancer types. Specifically, the CD47-high group exhibited a poorer prognosis for the cytotoxic CD8 + T cell Top group compared to the CD47-low group, suggesting a potential impairment of CD8 + T cell functionality by CD47. The exploration of mechanism identified enrichment of CD47-associated differentially expressed genes in the CD8 + T cell exhausted pathway in multiple cancer contexts. Further analyses focusing on the CD8 TCR Downstream Pathway and gene correlation patterns underscored the significant involvement of TNFRSF9 in mediating these effects. CONCLUSION: A robust association exists between CD47 and the exhaustion of CD8 + T cells, potentially enabling immune evasion by cancer cells and thereby contributing to adverse prognostic outcomes. Consequently, genes such as CD47 and those linked to T-cell exhaustion, notably TNFRSF9, present as promising dual antigenic targets, providing critical insights into the field of immunotherapy.

Liraglutide enhances the effect of checkpoint blockade through the inhibition of neutrophil extracellular traps in murine lung and liver cancers.

Glucagon-like peptide-1 (GLP-1) regulates glycemic excursions by augmenting insulin production and inhibiting glucagon secretion. Liraglutide, a long-acting GLP-1 analog, can improve glycemic control for treating type 2 diabetes and prevent neutrophil extravasation in inflammation. Here, we explored the role of liraglutide in the development and therapy of murine lung and liver cancers. In this study, liraglutide substantially decreased circulating neutrophil extracellular trap (NET) markers myeloperoxidase, elastase, and dsDNA in LLC and Hepa1-6 tumor-bearing mice. Furthermore, liraglutide downregulated NETs and reactive oxygen species (ROS) of neutrophils in the tumor microenvironment. Functionally, in vitro experiments showed that liraglutide reduced NET formation by inhibiting ROS. In addition, we showed that liraglutide enhanced the anti-tumoral efficiency of PD-1 inhibition in LLC and Hepa1-6 tumor-bearing C57BL/6 mice. However, the removal of NETs significantly weakened the antitumor efficiency of liraglutide. We further demonstrated that the long-term antitumor CD8+ T cell responses induced by the combination therapy rejected rechallenges by respective tumor cell lines. Taken together, our findings suggest that liraglutide may promote the anti-tumoral efficiency of PD-1 inhibition by reducing NETs in lung and liver cancers.

Exenatide enhanced the antitumor efficacy on PD-1 blockade by the attenuation of neutrophil extracellular traps.

Neutrophil extracellular traps (NETs) are extracellular webs of DNA, histones, and granular contents, such as myeloperoxidase (MPO) and elastase, which are released by neutrophils. Reactive oxygen species (ROS) are involved in NETs formation that promote tumor progress. Exenatide could downregulate ROS production in some cell types. However, it is unknown whether Exenatide could influence tumor progress through NETs. Here, we constructed the LLC-based lung cancer and MC38-based colon cancer models and found that Exenatide treatment decreased tumor infiltrated NETs and peripheral MPO-DNA complex and elastase. In addition, the in vitro study showed that Exenatide decreased NETs formation and release. Furthermore, flow cytometry analysis showed that Exenatide treatment reduced ROS production in tumor infiltrated and in vitro neutrophils. However, the ROS inhibitor DPI counteracted the decease of tumor infiltrated and in vitro NETs formation and release by Exenatide. Functionally, the Exenatide/αPD-1 combination therapy was superior to single therapy in restricting tumor growth. Removement of NETs by DNase I weaken the enhancement of αPD-1 treatment by Exenatide. The enriched tumor infiltrated, spleen and lymph node CD8+ T cells from combination therapy group secreted higher concentration of IFN-γ than single treatment. In addition, Exenatide exhibited no direct influence on IFN-γ secretion while purified NETs decreased IFN-γ secretion by CD8+ T cells. The rechallenge study showed that the combination therapy activated long-term tumor rejection. In summary, our findings suggested that Exenatide might be a promising therapeutic candidate for enhancing PD-1 blockade in tumor treatment.