CCR4 and neoplasm: Among the CCR4 binding chemokines, CCL17 (TARC) concentrations were not significantly different while the concentration of CCL22 (MDC) was significantly higher in tumors than in unaffected tissues (304±320 pg CCL22/mg total protein and 124±111 pg/mg in tumor and unaffected tissue, respectively, p<0.01), a finding that could explain the increased number of CCR4+ T cells in the tumor tissue.