CD68 and oral cavity squamous cell carcinoma: It has been shown that CD68 + HLA-DR + M1-type macrophage enhances tumor cell motility in hepatocellular carcinoma.[21] Exosomes in oral squamous cell carcinoma regulate the conversion of macrophage to M1, which promotes malignant tumor metastasis.[22] The pro-tumorigenic effects of M1 macrophages may be due to inflammatory cytokines.