PTGS2 and esophageal squamous cell carcinoma: Moreover, the expression levels of miR-101 and, COX-2 as well as PGE2 were negatively correlated according to the western blot of luciferase reporter assay results, indicating that miR-101 inhibit ESCC through COX-2 and that the miR-101 / COX-2 pathway may be very important in ESCC.