CCL5 and head and neck squamous cell carcinoma: To further explore the endogenous (epigenetic) and exogenous (health manner) factors impacting the expression of the four chemokines-CXCL9, CXCL10, CXCL11, and CCL5--the chromatin accessibility and the methylation status at the transcription initiation regions of CXCL9, CXCL10, CXCL11, and CCL5 were analyzed in the whole genome with TCGA HNSCC ATAC and methylation database.