Co-administration of PEA and URB597 reduces melanoma growth. Tumors were induced by s.c. injection of B16 cells in C57BL/6 mice. When tumor size reached a volume of approximately 20-40 mm2, animals were treated i.p. either with vehicle (n = 18) or with PEA (= 7), URB597 (n = 7) or both molecules (n = 20) (at 10 mg/kg/day, daily) for six days. (A) Tumor volume was measured each day. (B) Weight of tumors treated with vehicle (6 or 5 days of treatment) or PEA + URB597 (6 days of treatment) was measured at the end of the experiment. Significantly different (*P < 0.05; **P < 0.01; ***P < 0.001) from vehicle administration.