In view of the ability of ABCB1 to transport taxane as efflux pump [25,26], the up-regulation of ABCB1 induced by CCL20 in our current studies might account for the pharmacological intracellular abundance of taxane being lower in CCL20-overexpressing cells than vector cells, which promoted the taxane resistance of breast cancer cells. The gene discussed is CCL20; the disease is breast carcinoma.