We explored whether adipocyte culture medium affects the secreted chemokine profile of tumor cells, because adipocytes stimulate progression or metastasis of breast cancer cells, and chemokines secreted from tumor cells are involved in these processes. CCL20 expression was dramatically increased, and an NF-kappaB blocker completely inhibited adipocyte culture medium-induced CCL20 expression in MDA-MB-231 cells. We showed that adipocyte culture medium increased the production of TNF-alpha in MDA-MB-231 cells, which stimulated CCL20 expression in an autocrine fashion. Our data also showed that CCL20 increased the migration and invasiveness of MDA-MB-231 cells, but did not affect the proliferation of these cells.