Figure 1.

COX-2 inhibitors, PGE_1, and PGE₂ chemical structure (A). The prostaglandin E₂ (PGE₂) (pro-cancer) (a), the aspirin derivate named [2-acetoxy-(2-propynyl)benzoate]hexacarbonyldicobalt (Co-ASS) (b), the prostaglandin E₁ (PGE₁) (anticancer) (c) and the COX-2 selective inhibitor named celecoxib, (p-(5-p-Tolyl-3-(trifluoromethyl) pyrazol-1-yl)benzenesulfonamide) (d). Expression of COX-2, 5-LOX, and 12-LOX in cancer and the effect of inhibitors against these targets (B). Activation of 5-LOX-5, 12-LOX, and COX-2 has been reported in the development and progress of tumors from different tissues associated with the production of specific lipid peroxides and metabolites, such as PGE₂ (a). Some inhibitors of these LOX isoforms and COX-2 have emerged as potential therapeutical agents for cancer treatment, modulating the production of previously commented metabolites and by induction of cancer cell death (b).