CXCL8 and melanoma: Blocking IL-8 significantly impaired the proliferative effect of phEC-CM on human A375 melanoma cells (Fig. 7A–C), consisting with the inhibition of IL-8 receptors CXCR1 and CXCR2 by using specific small molecular inhibitor SB225002 (Fig. 7D and supplemental Fig. S11).