Fig. 4

M1-like polarization in macrophages activated by OSCC exosomes and in OSCC samples.a. Representative Scatter plots showed CD86 expression levels in THP-1-derived macrophages stimulated by exosomes from SCC25 and Cal27 for 24 h determined by flow cytometry. The histogram showed quantification for the percentage of CD86⁺ macrophages. Data were presented as the mean ± SD of three independent experiments, **p < 0.01, a significant difference compared with the control. b. Chromogenic double staining with CD80 (pink)/CD68 (brown) in primary OSCC samples. Cells double positive for CD80 and CD68 were observed in OSCC samples. Representative images shown are in 100× and 200× magnification; control images were presented in Additional file 4. c. Heat-map from the UCSC Xena Browser based on the primary TCGA HNSCC cohort depicted the gene expression relationship between the CD68 pan surface marker for macrophages and the M1 polarization surface marker CD80 or CD86. **p < 0.01, a significant correlation with CD68 expression was observed for both CD80 and CD86.D. Expression pattern of CD68, CD86, and CD80 in a validated primary OSCC cohort (n = 30)