CXCL12 and melanoma: Melanoma biopsies are segregated into two major subsets such as those infiltrated by T cells and those lacking T cell infiltration-tumors with a T cell-infiltrated phenotype differentially expressed chemokines CCL2, CCL3, CCL4, CCL5, CCL19, CCL21, CXCL9, CXCL10, CXCL11, and CXCL13 whereas all tumors irrespective of the T cell infiltration level expressed detectable levels of CXCL8/IL-8 and CXCL12/SDF-1 [11].