title: Role of 14-3-3 sigma in over-expression of P-gp by rifampin and paclitaxel stimulation through interaction with PXR.
abstract: In this study, we presented the role of 14-3-3σ to activate CK2-Hsp90β-PXR-MDR1 pathway on rifampin and paclitaxel treated LS174T cells and in vivo LS174T cell-xenografted nude mouse model. Following several in vitro and in vivo experiments, rifampin and paclitaxel were found to be stimulated the CK2-Hsp90β-PXR-MDR1 pathway. Of the proteins in this pathway, Pregnane X receptor (PXR) is a representative transcription factor of multidrug resistance protein 1 (MDR1). We constructed FLAG-PXR-LS174T stable cell lines and discovered 22 proteins that interacted with PXR on rifampin treatment. Among them, Hsp90β and 14-3-3σ were isolated for further study. Both the proteins were found to be localized in cytoplasm on rifampin treatment by using confocal microscopy. On the other hand, PXR was found to be localized in nucleus after rifampin and paclitaxel treatment by using cell fractionation assay. In Western blot analysis, rifampin did not influence the expression of 14-3-3σ protein. Transient transfection of 14-3-3σ into LS174T cells induced overexpression of PXR; however, P-glycoprotein (P-gp) was not changed significantly. P-gp overexpression was induced only when 14-3-3σ transfected LS174T cells were treated with rifampin and paclitaxel, whereas 14-3-3σ inhibition by nonpeptidic inhibitor, BV02 and 14-3-3σ siRNA reduced rifampin induced PXR and P-gp expression. Cell survival rates were much higher at 14-3-3σ-LS174T stable cell lines than LS174T cells following paclitaxel and vincristine treatment. This data indicates that 14-3-3σ contributes to P-gp overexpression through interaction with PXR with rifampin and paclitaxel treatment.
authors.affiliation: Department of Pharmacology, Catholic Kwandong University College of Medicine, Gangneung 25601, Republic of Korea; The Institute for Clinical and Translational Research, Catholic Kwandong University College of Medicine, Gangneung 25601, Republic of Korea. Electronic address: kerorosw@gmail.com.
authors.forename: So Won
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan 47392, Republic of Korea; Department of Pharmacy, Noakhali Science and Technology University, Sonapur, Noakhali 3814, Bangladesh.
authors.lastname: Md Hasanuzzaman
authors.affiliation: Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan 47392, Republic of Korea.
authors.forename: Munju
authors.initials: M
authors.lastname: Cho
authors.affiliation: Department of Pharmacology, Catholic Kwandong University College of Medicine, Gangneung 25601, Republic of Korea.
authors.forename: Nam Hyun
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Department of Pharmacology, Catholic Kwandong University College of Medicine, Gangneung 25601, Republic of Korea.
authors.forename: Hye-Young
authors.initials: HY
authors.lastname: Choi
authors.affiliation: Department of Pharmacology, Yonsei University College of Medicine, Seoul 03722, Republic of Korea.
authors.forename: Jung Woo
authors.initials: JW
authors.lastname: Han
authors.affiliation: Department of Chemistry, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Hyun June
authors.initials: HJ
authors.lastname: Park
authors.affiliation: Department of Anatomy, School of Medicine, Kyungpook National University, Daegu 41944, Republic of Korea; Bio-Medical Research Institute, Kyungpook National University Hospital, Daegu 41944, Republic of Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Oh
authors.affiliation: Department of Pharmacology and PharmacoGenomics Research Center, Inje University College of Medicine, Busan 47392, Republic of Korea; Department of Clinical Pharmacology, Inje University Busan Paik Hospital, Busan 47392, Republic of Korea. Electronic address: phshinjg@gmail.com.
authors.forename: Jae-Gook
authors.initials: JG
authors.lastname: Shin
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism*; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D001665:Binding Sites; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002470:Cell Survival / Q000187:drug effects; D002853:Chromatography, Liquid; D005095:Exoribonucleases / Q000378:metabolism*; D005260:Female; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D008819:Mice, Nude; D008954:Models, Biological; D017239:Paclitaxel / Q000494:pharmacology*; D000077297:Pregnane X Receptor; D011485:Protein Binding / Q000187:drug effects; D011987:Receptors, Steroid / Q000737:chemistry / Q000378:metabolism*; D012293:Rifampin / Q000494:pharmacology*; D053719:Tandem Mass Spectrometry
chemical_list: D048948:14-3-3 Proteins; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D018841:HSP90 Heat-Shock Proteins; D000077297:Pregnane X Receptor; D011987:Receptors, Steroid; D005095:Exoribonucleases; C413442:SFN protein, human; D017239:Paclitaxel; D012293:Rifampin
keywords: 14-3-3 sigma; Hsp90 beta; Multidrug Resistance Protein 1 (MDR1); Paclitaxel; Pregnane X Receptor (PXR); Rifampin