15-PGDH can catalyze the oxidation of the 15 (S) -hydroxyl group of prostaglandin E2 (PGE2) which is a pro-inflammatory lipid medium promoting carcinogenesis, so the downregulation of miRNA-26 may be related to the ability of ω-3PUFA to inhibit cancers.265 Interestingly, ω-3PUFA also directly upregulates 15-PGDH which acts as a tumor suppressor in lung and colon cancer.266,267 Several compounds that can induce 15-PGDH expression have been reported, including histone deacetylase inhibitors, nonsteroidal anti-inflammatory drugs, and peroxisome proliferator-activated receptor-γ agonists. The gene discussed is HPGD; the disease is cancer.