ACKR3 and head and neck squamous cell carcinoma: Furthermore, the aberrant expression levels of all CXCR members in HNSCC compared to the healthy tissues were revealed by the analysis results, especially the significant downregulation of CXCR2 in HNSCC tissues, while the other CXCRs, namely CXCR1 and CXCR3 to CXCR7, were significantly upregulated in HNSCC tissues (Fig. 1C).