Not only did in vitro immunoassay show reduced level of PTGR2 product 13,14-dihydro-15-keto-PGE2 (Fig 3D and S2B Fig), LC/MS quantification further confirmed the higher level of 15-keto-PGE2 and reduced level of 13,14-dihydro-15-keto-PGE2 in PTGR2-silenced pancreatic cancer cells as compared to controls (Fig 3E and 3F and S2C and S2D Fig). This evidence concerns the gene PTGR2 and familial pancreatic carcinoma.