We used CCR2 specific antagonists (20 μM, RS102895 hydrochloride, MedChemExpress, Monmouth Junction, NJ) and CCR4 specific antagonists (100 nM, AZD2098, MedChemExpress, Monmouth Junction, NJ) or silencing short interfering RNA to block CCR2 and CCR4 in HSC6 cells and SCC15 cells, and results revealed that suppression of CCR4 instead of CCR2, could reverse CCL2-promoted HNSCC cells migration in both Transwell assay and wound healing (Fig. 2F–I). This evidence concerns the gene CCL2 and head and neck squamous cell carcinoma.