PTGS2 and cancer: Our previous studies showed that delta-5-desaturase knockdown (via siRNA) in the human colon cancer cell line HCA-7 colony 29 (HCA-7/C29, cells that express Cyclooxygenase-2) could promote the production of an anti-cancer byproduct, 8-hydroxyoctanoic acid (8-HOA), from Cyclooxygenase-2-catalyzed dihomo-γ-linolenic acid peroxidation, and thus inhibit cancer cell growth and migration [24–27].