Arachidonic acid seems to act as a death messenger for the cell and its depletion by overexpressed cyclooxygenase-2 leads to further synthesis of prostaglandin PGE2 and upregulation of vascular endothelial growth factors (VEGF), which in turn favors tumor neoangiogenesis, thereby supporting local tumor progression and metastatic spreading. This evidence concerns the gene PTGS2 and neoplasm.