In colon cancers, cyclooxygenase-2 (COX-2), an enzyme that catalyzes the conversion of arachidonic acid to prostaglandin H2 (PGH2), is overexpressed in CAFs surrounding colon adenocarcinomas, leading to a buildup of intratumoral PGE2 [61,115]. The gene discussed is PTGS2; the disease is malignant colon neoplasm.