CXCL9 and metastatic melanoma: More importantly, these in vivo observations in mice translate into clinical evidence with expression of CXCL9 and CXCL10 in primary human melanoma correlating with increased CD8+ T-cell infiltration.57 Similarly, in metastatic melanoma, increased CD8+ T-cell infiltration was associated with enhanced expression of CCL3, CCL4, CCL5, CXCL9 and CXCL10.58 Furthermore, overexpression of CCR5 and CXCR3 ligands correlated with responsiveness to treatment.