Journal: Journal for Immunotherapy of Cancer
Article Title: IL-4-STAT6-induced high Siglec-G/10 expression aggravates the severe immune suppressive tumor microenvironment and impedes the efficacy of immunotherapy in head and neck squamous cell carcinoma
doi: 10.1136/jitc-2025-011474
Figure Lengend Snippet: Siglec-G/10 promotes HNSCC transplant-tumor growth by reducing CD8+T cells infiltration. ( a ) Schematic illustration of Siglec-G-Fc and PD-1/PD-L1 inhibitory BMS-1 therapy. WT mice were subcutaneously inoculated with MTCQ1 HNSCC cells and administered with Siglec-G-Fc and BMS-1 or left untreated on days 3, 7, 10, 14 and 17. The tumor volume was monitored. ( b, c ) Volumes and weights of MTCQ1 subcutaneous tumorigenesis (n=5 mice per group), Scale bar: 1 cm. ( d, e ) Representative images of multiplex immunofluorescence staining of CD8+ (green) and Siglec-G+ (red) are shown, and quantification analysis was performed in tumor tissues (n=5 fields of five mice per group), Scale bar: 100 µm. ( f ) The exhibition of subcutaneous tumorigenesis in Siglecg +/+ mice and Siglecg −/− mice. ( g ) The exhibition of isolated tumors. ( h, i ) Tumor growth curve and tumor weight of MTCQ1 cells derived subcutaneous tumorigenesis model in two groups for 31 days (n=5). ( j ) Flow cytometry analysis for percentage of Siglec-G+cells in CD45+and CD45- subsets in tumors; ( k ) Flow cytometry analysis for infiltration of macrophages, monocytes, neutrophils, dendritic cells, T cells, B cells and NK cells in tumors. ( l ) Flow cytometry analysis for percentage of CD8+T cells in tumors. ( m, n ) Representative images of multiplex immunofluorescence staining of CD8+ (green) and F4/80+ (red) are shown, and quantification analysis was performed in tumor tissues (n=6 fields of six mice per group), Scale bar: 50 µm. ( o ) Representative images of multiplex immunofluorescence staining of F4/80+ (red), Siglec-G+ (green) and PD-L1+ (gold) are shown, and quantification analysis was performed in tumor tissues (n=6 fields of six mice per group), Scale bar: 100 µm. ns: not significant (p>0.05), *p<0.05, **p<0.01. Data are expressed as mean±SD. BMS-1: PD-1/PD-L1 inhibitor 1; DCs: dendritic cells; HNSCC: head and neck squamous cell carcinoma; i.p.: intraperitoneal; NK: natural killer; PD-1: programmed cell death protein 1; PD-L1: programmed cell death ligand 1; Siglec: sialic acid binding immunoglobulin-like lectin; WT: wild type.
Article Snippet: Siglec-G-Fc protein (#TMPJ-01201, TargetMol, USA) has an accession number of Q80ZE3 and its amino acid sequence extends from Met19 to Lys543.
Techniques: Multiplex Assay, Immunofluorescence, Staining, Isolation, Derivative Assay, Flow Cytometry, Binding Assay