title: Regulation of UGT2B Expression and Activity by miR-216b-5p in Liver Cancer Cell Lines.
abstract: The UDP-glucuronosyltransferase (UGT) 2B enzymes are important in the detoxification of a variety of endogenous and exogenous compounds, including many hormones, drugs, and carcinogens. Identifying novel mechanisms governing their expression is important in understanding patient-specific response to drugs and cancer risk factors. In silico prediction algorithm programs were used to screen for microRNAs (miRNAs) as potential regulators of UGT2B enzymes, with miR-216b-5p identified as a potential candidate. Luciferase data suggested the presence of a functional miR-216b-5p binding motif within the 3' untranslated regions of UGTs 2B7, 2B4, and 2B10. Overexpression of miR-216b-5p mimics significantly repressed UGT2B7 (P < 0.001) and UGT2B10 (P = 0.0018) mRNA levels in HuH-7 cells and UGT2B4 (P < 0.001) and UGT2B10 (P = 0.018) mRNA in Hep3B cells. UGT2B7 protein levels were repressed in both HuH-7 and Hep3B cells in the presence of increasing miR-216b-5p concentrations, corresponding with significant (P < 0.001 and P = 0.011, respectively) decreases in glucuronidation activity against the UGT2B7-specific substrate epirubicin. Inhibition of endogenous miR-216b-5p levels significantly increased UGT2B7 mRNA levels in HuH-7 (P = 0.021) and Hep3B (P = 0.0068) cells, and increased epirubicin glucuronidation by 85% (P = 0.057) and 50% (P = 0.012) for HuH-7 and Hep3B cells, respectively. UGT2B4 activity against codeine and UGT2B10 activity against nicotine were significantly decreased in both HuH-7 and Hep3B cells (P < 0.001 and P = 0.0048, and P = 0.017 and P = 0.043, respectively) after overexpression of miR-216b-5p mimic. This is the first evidence that miRNAs regulate UGT 2B7, 2B4, and 2B10 expression, and that miR-216b-5p regulation of UGT2B proteins may be important in regulating the metabolism of UGT2B substrates.
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland (D.F.D.); Department of Pulmonary Medicine, Penn State University College of Medicine, Hershey, Pennsylvania (F.T.I.); and Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington (A.K.S., G.C., C.W., P.L.).
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Dluzen
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland (D.F.D.); Department of Pulmonary Medicine, Penn State University College of Medicine, Hershey, Pennsylvania (F.T.I.); and Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington (A.K.S., G.C., C.W., P.L.).
authors.forename: Aimee K
authors.initials: AK
authors.lastname: Sutliff
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland (D.F.D.); Department of Pulmonary Medicine, Penn State University College of Medicine, Hershey, Pennsylvania (F.T.I.); and Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington (A.K.S., G.C., C.W., P.L.).
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland (D.F.D.); Department of Pulmonary Medicine, Penn State University College of Medicine, Hershey, Pennsylvania (F.T.I.); and Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington (A.K.S., G.C., C.W., P.L.).
authors.forename: Christy J W
authors.initials: CJ
authors.lastname: Watson
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland (D.F.D.); Department of Pulmonary Medicine, Penn State University College of Medicine, Hershey, Pennsylvania (F.T.I.); and Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington (A.K.S., G.C., C.W., P.L.).
authors.forename: Faoud T
authors.initials: FT
authors.lastname: Ishmael
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, Maryland (D.F.D.); Department of Pulmonary Medicine, Penn State University College of Medicine, Hershey, Pennsylvania (F.T.I.); and Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington (A.K.S., G.C., C.W., P.L.) phil.lazarus@wsu.edu.
authors.forename: Philip
authors.initials: P
authors.lastname: Lazarus
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D001483:Base Sequence; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D014453:Glucuronosyltransferase / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D035683:MicroRNAs / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D020413:3' Untranslated Regions; C575482:MIRN216 microRNA, human; D035683:MicroRNAs; D014453:Glucuronosyltransferase