c-Met enforces proinflammatory and migratory features of human activated CD4+ T cells

c-Met+ Cytotoxic T Lymphocytes Exhibit Enhanced Cytotoxicity in Mice and Humans In Vitro Tumor Models

CD8+ cytotoxic T lymphocytes (CTLs) play a crucial role in anti-tumor immunity. In a previous study, we identified a subset of murine effector CTLs expressing the hepatocyte growth factor (HGF) receptor, c-Met (c-Met+ CTLs), that are endowed with enhanced cytolytic capacity. HGF directly inhibited the cytolytic function of c-Met+ CTLs, both in 2D in vitro assays and in vivo, leading to reduced T cell responses against metastatic melanoma. To further investigate the role of c-Met+ CTLs in a three-dimensional (3D) setting, we studied their function within B16 melanoma spheroids and examined the impact of cell-cell contact on the modulation of inhibitory checkpoint molecules' expression, such as KLRG1, PD-1, and CTLA-4. Additionally, we evaluated the cytolytic capacity of human CTL clones expressing c-Met (c-Met+) and compared it to c-Met- CTL clones. Our results indicated that, similar to their murine counterparts, c-Met+ human CTL clones exhibited increased cytolytic activity compared to c-Met- CTL clones, and this enhanced function was negatively regulated by the presence of HGF. Taken together, our findings highlight the potential of targeting the HGF/c-Met pathway to modulate CTL-mediated anti-tumor immunity. This research holds promise for developing strategies to enhance the effectiveness of CTL-based immunotherapies against cancer.

Silencing CircEIF3I/miR-526b-5p Axis Epigenetically Targets HGF/c-Met Signal to Hinder the Malignant Growth, Metastasis and Angiogenesis of Hepatocellular Carcinoma

BACKGROUND

Hepatocyte growth factor (HGF)/c-mesenchymal-epithelial transition factor (c-Met) is important for the diagnosis and prognosis of hepatocellular carcinoma (HCC). Circular RNAs (circRNAs) are key regulators of HCC progression, and this study focused on circRNA eukaryotic translation initiation factor 3 subunit I (circEIF3I) with HGF/c-Met in HCC.

METHODS

Levels of circEIF3I, microRNA (miR)-526b-5p, HGF, E-cadherin, N-cadherin, and Vimentin were detected by Gene Expression Omnibus database, quantitative PCR and western blotting. Cell functions were measured by detecting cell growth (cell proliferation assay with WST-1 and EdU, colony formation assay, flow cytometry, caspase 3 activity assay, and nude mouse tumorigenicity assay), metastasis (transwell assay and western blotting), angiogenesis (endothelial tube formation assay). Molecular interaction was determined dual-luciferase reporter assay, RNA immunoprecipitation, and Pearson correlation analysis.

RESULTS

Expression of circEIF3I was upregulated in HCC tissues. Knockdown of circEIF3I suppressed cell proliferation epithelial-mesenchymal transition, migration, invasion and tube formation ability but promoted apoptosis of HCC cells. CircEIF3I could sponge miR-526b-5pto regulate downstream HGF. Functionally, circEIF3I regulation in HCC cell progression was associated with miR-526b-5p sponging function and HGF upregulation could attenuate tumor-inhibiting roles of miR-526b-5p. HCC tumor growth was delayed by interfering circEIF3I.

CONCLUSION

CircEIF3I was an oncogenic circRNA in HCC-, and interfering circEIF3I exhibited anti-HCC activity via circEIF3I-miR-526b-5p-HGF/c-Met pathway.

CD4+c-Met+Itgα4+ T cell subset promotes murine neuroinflammation

Objective

c-Met, a tyrosine kinase receptor, is the unique receptor for hepatocyte growth factor (HGF). The HGF/c-Met axis is reported to modulate cell migration, maturation, cytokine production, and antigen presentation. Here, we report that CD4⁺c-Met⁺ T cells are detected at increased levels in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis (MS).

Methods

c-Met expression by CD4⁺ T cells was analyzed mostly by flow cytometry and by immunohistochemistry from mice and human PBMCs. The in vivo role of CD4⁺c-Met⁺ T cells was assessed in EAE.

Results

CD4⁺c-Met⁺ T cells found in the CNS during EAE peak disease are characterized by a pro-inflammatory phenotype skewed towards a Th1 and Th17 polarization, with enhanced adhesion and transmigration capacities correlating with increased expression of integrin α4 (Itgα4). The adoptive transfer of Itgα4-expressing CD4⁺Vα3.2⁺c-Met⁺ T cells induces increased disease severity compared to CD4⁺Vα3.2⁺c-Met⁻ T cells. Finally, CD4⁺c-Met⁺ T cells are detected in the brain of MS patients, as well as in the blood with a higher level of Itgα4. These results highlight c-Met as an immune marker of highly pathogenic pro-inflammatory and pro-migratory CD4⁺ T lymphocytes associated with neuroinflammation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-022-02461-7.