Synergistic pharmaceutical compositions and the methods for preventing and treating proliferative diseases such as cancer and psoriasis. The compositions comprise synergistic combinations of: (i) an acyl-CoA-synthetase enzyme inhibitor (AcsI4), (ii) a compound having an inhibiting effect on enzymes with cyclooxygenase activity (COX)； and (iii) a compound selected from a 5-lypoxygenase enzyme (LOX-5) inhibitor and a leukotriene receptor antagonist.
