CXCR4 and nasopharyngeal carcinoma: These fibroblasts can also secrete varied chemokines, such as CXCL9, CXCL10 and CXCL12 which can promote tumor growth and has chemoattractant properties that stimulate the migration of CXCR3+/CXCR4+ suppressive Tregs and cytotoxic T cells into the NPC microenvironment (24, 56).