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Ni C, Hong M. Oligomerization of drug transporters: Forms, functions, and mechanisms. Acta Pharm Sin B 2024; 14:1924-1938. [PMID: 38799641 PMCID: PMC11119549 DOI: 10.1016/j.apsb.2024.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 12/07/2023] [Accepted: 01/05/2024] [Indexed: 05/29/2024] Open
Abstract
Drug transporters are essential players in the transmembrane transport of a wide variety of clinical drugs. The broad substrate spectra and versatile distribution pattern of these membrane proteins infer their pharmacological and clinical significance. With our accumulating knowledge on the three-dimensional structure of drug transporters, their oligomerization status has become a topic of intense study due to the possible functional roles carried out by such kind of post-translational modification (PTM). In-depth studies of oligomeric complexes formed among drug transporters as well as their interactions with other regulatory proteins can help us better understand the regulatory mechanisms of these membrane proteins, provide clues for the development of novel drugs, and improve the therapeutic efficacy. In this review, we describe different oligomerization forms as well as their structural basis of major drug transporters in the ATP-binding cassette and solute carrier superfamilies, summarize our current knowledge on the influence of oligomerization for protein expression level and transport function of these membrane proteins, and discuss the regulatory mechanisms of oligomerization. Finally, we highlight the challenges associated with the current oligomerization studies and propose some thoughts on the pharmaceutical application of this important drug transporter PTM.
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Affiliation(s)
- Chunxu Ni
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Mei Hong
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, South China Agricultural University, Guangzhou 510642, China
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2
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Zhang X, Liu W, Edaki K, Nakazawa Y, Takahashi S, Sunakawa H, Mizoi K, Ogihara T. Slug Mediates MRP2 Expression in Non-Small Cell Lung Cancer Cells. Biomolecules 2022; 12:biom12060806. [PMID: 35740931 PMCID: PMC9220960 DOI: 10.3390/biom12060806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 02/01/2023] Open
Abstract
Transcriptional factors, such as Snail, Slug, and Smuc, that cause epithelial-mesenchymal transition are thought to regulate the expression of Ezrin, Radixin, and Moesin (ERM proteins), which serve as anchors for efflux transporters on the plasma membrane surface. Our previous results using lung cancer clinical samples indicated a correlation between Slug and efflux transporter MRP2. In the current study, we aimed to evaluate the relationships between MRP2, ERM proteins, and Slug in lung cancer cells. HCC827 cells were transfected by Mock and Slug plasmid. Both mRNA expression levels and protein expression levels were measured. Then, the activity of MRP2 was evaluated using CDCF and SN-38 (MRP2 substrates). HCC827 cells transfected with the Slug plasmid showed significantly higher mRNA expression levels of MRP2 than the Mock-transfected cells. However, the mRNA expression levels of ERM proteins did not show a significant difference between Slug-transfected cells and Mock-transfected cells. Protein expression of MRP2 was increased in Slug-transfected cells. The uptake of both CDCF and SN-38 was significantly decreased after transfection with Slug. This change was abrogated by treatment with MK571, an MRP2 inhibitor. The viability of Slug-transfected cells, compared to Mock cells, significantly increased after incubation with SN-38. Thus, Slug may increase the mRNA and protein expression of MRP2 without regulation by ERM proteins in HCC827 cells, thereby enhancing MRP2 activity. Inhibition of Slug may reduce the efficacy of multidrug resistance in lung cancer.
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Affiliation(s)
- Xieyi Zhang
- Laboratory of Biopharmaceutics, Department of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-chou, Takasaki-shi 370-0033, Gunma, Japan; (K.E.); (Y.N.); (S.T.); (K.M.); (T.O.)
- Correspondence: ; Tel.: +81-273521180; Fax: +81-273521118
| | - Wangyang Liu
- Laboratory of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki-shi 370-0033, Gunma, Japan; (W.L.); (H.S.)
| | - Kazue Edaki
- Laboratory of Biopharmaceutics, Department of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-chou, Takasaki-shi 370-0033, Gunma, Japan; (K.E.); (Y.N.); (S.T.); (K.M.); (T.O.)
| | - Yuta Nakazawa
- Laboratory of Biopharmaceutics, Department of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-chou, Takasaki-shi 370-0033, Gunma, Japan; (K.E.); (Y.N.); (S.T.); (K.M.); (T.O.)
| | - Saori Takahashi
- Laboratory of Biopharmaceutics, Department of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-chou, Takasaki-shi 370-0033, Gunma, Japan; (K.E.); (Y.N.); (S.T.); (K.M.); (T.O.)
| | - Hiroki Sunakawa
- Laboratory of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki-shi 370-0033, Gunma, Japan; (W.L.); (H.S.)
| | - Kenta Mizoi
- Laboratory of Biopharmaceutics, Department of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-chou, Takasaki-shi 370-0033, Gunma, Japan; (K.E.); (Y.N.); (S.T.); (K.M.); (T.O.)
| | - Takuo Ogihara
- Laboratory of Biopharmaceutics, Department of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-chou, Takasaki-shi 370-0033, Gunma, Japan; (K.E.); (Y.N.); (S.T.); (K.M.); (T.O.)
- Laboratory of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki-shi 370-0033, Gunma, Japan; (W.L.); (H.S.)
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Kobori T, Tanaka C, Tameishi M, Urashima Y, Ito T, Obata T. Role of Ezrin/Radixin/Moesin in the Surface Localization of Programmed Cell Death Ligand-1 in Human Colon Adenocarcinoma LS180 Cells. Pharmaceuticals (Basel) 2021; 14:ph14090864. [PMID: 34577564 PMCID: PMC8467328 DOI: 10.3390/ph14090864] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/23/2021] [Accepted: 08/26/2021] [Indexed: 12/30/2022] Open
Abstract
Programmed cell death ligand-1 (PD-L1), an immune checkpoint protein highly expressed on the cell surface in various cancer cell types, binds to programmed cell death-1 (PD-1), leading to T-cell dysfunction and tumor survival. Despite clinical successes of PD-1/PD-L1 blockade therapies, patients with colorectal cancer (CRC) receive little benefit because most cases respond poorly. Because high PD-L1 expression is associated with immune evasion and poor prognosis in CRC patients, identifying potential modulators for the plasma membrane localization of PD-L1 may represent a novel therapeutic strategy for enhancing the efficacy of PD-1/PD-L1 blockade therapies. Here, we investigated whether PD-L1 expression in human colorectal adenocarcinoma cells (LS180) is affected by ezrin/radixin/moesin (ERM), functioning as scaffold proteins that crosslink plasma membrane proteins with the actin cytoskeleton. We observed colocalization of PD-L1 with all three ERM proteins in the plasma membrane and detected interactions involving PD-L1, the three ERM proteins, and the actin cytoskeleton. Furthermore, gene silencing of ezrin and radixin, but not of moesin, substantially decreased the expression of PD-L1 on the cell surface without affecting its mRNA level. Thus, in LS180 cells, ezrin and radixin may function as scaffold proteins mediating the plasma membrane localization of PD-L1, possibly by post-translational modification.
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Affiliation(s)
- Takuro Kobori
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan; (T.K.); (C.T.); (M.T.); (Y.U.)
| | - Chihiro Tanaka
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan; (T.K.); (C.T.); (M.T.); (Y.U.)
| | - Mayuka Tameishi
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan; (T.K.); (C.T.); (M.T.); (Y.U.)
| | - Yoko Urashima
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan; (T.K.); (C.T.); (M.T.); (Y.U.)
| | - Takuya Ito
- Laboratory of Natural Medicines, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan;
| | - Tokio Obata
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan; (T.K.); (C.T.); (M.T.); (Y.U.)
- Correspondence: ; Tel.: +81-721-24-9371
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Multidrug resistance-associated protein 2 is negatively regulated by oxidative stress in rat intestine via a posttranslational mechanism. Impact on its membrane barrier function. Toxicology 2021; 460:152873. [PMID: 34303734 DOI: 10.1016/j.tox.2021.152873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/29/2021] [Accepted: 07/21/2021] [Indexed: 11/20/2022]
Abstract
Oxidative stress (OS) is a key factor in the development of gastrointestinal disorders, in which the intestinal barrier is altered. However, the Multidrug resistance-associated protein 2 (Mrp2) status, an essential component of the intestinal transcellular barrier exhibiting pharmaco-toxicological relevance by limiting the orally ingested toxicants and drugs absorption, has not been investigated. We here evaluated the short-term effect of OS on Mrp2 by treatment of isolated rat intestinal sacs with tert-butyl hydroperoxide (TBH) for 30 min. OS induction by TBH (250 and 500 μM) was confirmed by increased lipid peroxidation end products, decreased reduced glutathione (GSH) content and altered antioxidant enzyme activities. Under this condition, assessment of Mrp2 distribution between brush border (BBM) and intracellular (IM) membrane fractions, showed that Mrp2 protein decreased in BBM and increased in IM, consistent with an internalization process. This was associated with decreased efflux activity and, consequently, impaired barrier function. Subsequent incubation with N-Acetyl-L-Cysteine (NAC, 1 mM) reestablished GSH content and reverted concomitantly the alteration in Mrp2 localization and function induced by TBH. Cotreatment with a specific inhibitor of classic calcium-dependent Protein Kinase C (cPKC) implicated this kinase in TBH-effects. In conclusion, we demonstrated a negative posttranslational regulation of rat intestinal Mrp2 after short-term exposition to OS, a process likely mediated by cPKC and dependent on intracellular GSH content. The concomitant impairment of the Mrp2 barrier function may have implications in xenobiotic absorption and toxicity in a variety of human diseases linked to OS, with notable consequences on the toxicity/safety of therapeutic agents.
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Kobori T, Tameishi M, Tanaka C, Urashima Y, Obata T. Subcellular distribution of ezrin/radixin/moesin and their roles in the cell surface localization and transport function of P-glycoprotein in human colon adenocarcinoma LS180 cells. PLoS One 2021; 16:e0250889. [PMID: 33974673 PMCID: PMC8112653 DOI: 10.1371/journal.pone.0250889] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/15/2021] [Indexed: 12/20/2022] Open
Abstract
The ezrin/radixin/moesin (ERM) family proteins act as linkers between the actin cytoskeleton and P-glycoprotein (P-gp) and regulate the plasma membrane localization and functionality of the latter in various cancer cells. Notably, P-gp overexpression in the plasma membrane of cancer cells is a principal factor responsible for multidrug resistance and drug-induced mutagenesis. However, it remains unknown whether the ERM proteins contribute to the plasma membrane localization and transport function of P-gp in human colorectal cancer cells in which the subcellular localization of ERM has yet to be determined. This study aimed to determine the gene expression patterns and subcellular localization of ERM and P-gp and investigate the role of ERM proteins in the plasma membrane localization and transport function of P-gp using the human colon adenocarcinoma cell line LS180. Using real-time reverse transcription polymerase chain reaction and immunofluorescence analyses, we showed higher levels of ezrin and moesin mRNAs than those of radixin mRNA in these cells and preferential distribution of all three ERM proteins on the plasma membrane. The ERM proteins were highly colocalized with P-gp. Additionally, we show that the knockdown of ezrin, but not of radixin and moesin, by RNA interference significantly decreased the cell surface expression of P-gp in LS180 cells without affecting the mRNA expression of P-gp. Furthermore, gene silencing of ezrin substantially increased the intracellular accumulation of rhodamine123, a typical P-gp substrate, with no alterations in the plasma membrane permeability of Evans blue, a passive transport marker. In conclusion, ezrin may primarily regulate the cell surface localization and transport function of P-gp as a scaffold protein without influencing the transcriptional activity of P-gp in LS180 cells. These findings should be relevant for treating colorectal cancer, which is the second leading cause of cancer-related deaths in males and females combined.
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Affiliation(s)
- Takuro Kobori
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Mayuka Tameishi
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Chihiro Tanaka
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Yoko Urashima
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
| | - Tokio Obata
- Laboratory of Clinical Pharmaceutics, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka, Japan
- * E-mail:
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Ogihara T, Mizoi K, Kamioka H, Yano K. Physiological Roles of ERM Proteins and Transcriptional Regulators in Supporting Membrane Expression of Efflux Transporters as Factors of Drug Resistance in Cancer. Cancers (Basel) 2020; 12:E3352. [PMID: 33198344 PMCID: PMC7696277 DOI: 10.3390/cancers12113352] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/06/2020] [Accepted: 11/10/2020] [Indexed: 12/23/2022] Open
Abstract
One factor contributing to the malignancy of cancer cells is the acquisition of drug resistance during chemotherapy via increased expression of efflux transporters, such as P-glycoprotein (P-gp), multidrug resistance-associated proteins (MRPs), and breast cancer resistance protein (BCRP). These transporters operate at the cell membrane, and are anchored in place by the scaffold proteins ezrin (Ezr), radixin (Rdx), and moesin (Msn) (ERM proteins), which regulate their functional activity. The identity of the regulatory scaffold protein(s) differs depending upon the transporter, and also upon the tissue in which it is expressed, even for the same transporter. Another factor contributing to malignancy is metastatic ability. Epithelial-mesenchymal transition (EMT) is the first step in the conversion of primary epithelial cells into mesenchymal cells that can be transported to other organs via the blood. The SNAI family of transcriptional regulators triggers EMT, and SNAI expression is used is an indicator of malignancy. Furthermore, EMT has been suggested to be involved in drug resistance, since drug excretion from cancer cells is promoted during EMT. We showed recently that ERM proteins are induced by a member of the SNAI family, Snail. Here, we first review recent progress in research on the relationship between efflux transporters and scaffold proteins, including the question of tissue specificity. In the second part, we review the relationship between ERM scaffold proteins and the transcriptional regulatory factors that induce their expression.
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Affiliation(s)
- Takuo Ogihara
- Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare, 60, Nakaorui-machi, Takasaki, Gunma 370-0033, Japan;
| | - Kenta Mizoi
- Faculty of Pharmacy, Takasaki University of Health and Welfare, 60, Nakaorui-machi, Takasaki, Gunma 370-0033, Japan; (K.M.); (K.Y.)
| | - Hiroki Kamioka
- Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare, 60, Nakaorui-machi, Takasaki, Gunma 370-0033, Japan;
| | - Kentaro Yano
- Faculty of Pharmacy, Takasaki University of Health and Welfare, 60, Nakaorui-machi, Takasaki, Gunma 370-0033, Japan; (K.M.); (K.Y.)
- Laboratory of Drug Metabolism and Pharmacokinetics, Yokohama University of Pharmacy, 601, Matano-cho, Totsuka-ku, Yokohama, Kanagawa 245-0066, Japan
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Arana MR, Dominguez CJ, Zecchinati F, Tocchetti GN, Mottino AD, Villanueva SSM. Role of interleukin 1 beta in the regulation of rat intestinal multidrug resistance-associated protein 2 under conditions of experimental endotoxemia. Toxicology 2020; 441:152527. [PMID: 32553669 DOI: 10.1016/j.tox.2020.152527] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 06/12/2020] [Accepted: 06/14/2020] [Indexed: 12/26/2022]
Abstract
Multidrug resistance-associated protein 2 (Mrp2), expressed at the brush border membrane (BBM) of the enterocyte, is an ABC transporter with relevant intestinal barrier function. Its toxicological relevance lies in preventing absorption and tissue accumulation of dietary contaminants, drugs, and potentially harmful endogenous metabolites. Expression and activity of intestinal Mrp2 is downregulated in LPS-induced endotoxemia. In addition, confocal microscopy studies demonstrated internalization of the transporter to endocytic vesicles. Since IL-1β plays an important role as early mediator of LPS-inflammatory responses, we evaluated whether IL-1β mediates LPS-induced impairment of Mrp2 function. Two protocols were used: I) In vivo administration of LPS (5 mg/kg b.wt., i.p., single dose) to rats in simultaneous with administration of anti-IL-1β (25 μg/kg b.wt., i.p., 4 doses), followed by studies of Mrp2 expression, localization and activity, 24 h after LPS administration; II) In vitro incubation of isolated intestinal sacs with IL-1β (10 ng/mL) for 30 min, followed by analysis of Mrp2 activity and localization. We found that in vivo immunoneutralization of IL-1β partially prevented the decrease of Mrp2 protein expression and activity as well as its internalization to intracellular domains induced by LPS. Involvement of IL-1β in the alteration of Mrp2 localization and activity was more directly demonstrated in isolated intestinal sacs, as incubation with IL-1β resulted in detection of Mrp2 in intracellular regions of the enterocyte in simultaneous with alteration of transport activity. In conclusion, IL-1β induces early internalization of intestinal Mrp2, which could partially explain loss of expression at the BBM under conditions of experimental endotoxemia. Concomitant impairment of Mrp2-dependent barrier function may have pathophysiological relevance since IL-1β mediates the effect of many local and systemic inflammatory processes.
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Affiliation(s)
- Maite Rocío Arana
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR). Suipacha 570, 2000, Rosario, Argentina
| | - Camila Juliana Dominguez
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR). Suipacha 570, 2000, Rosario, Argentina
| | - Felipe Zecchinati
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR). Suipacha 570, 2000, Rosario, Argentina
| | - Guillermo Nicolás Tocchetti
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR). Suipacha 570, 2000, Rosario, Argentina
| | - Aldo Domingo Mottino
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR). Suipacha 570, 2000, Rosario, Argentina
| | - Silvina Stella Maris Villanueva
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR). Suipacha 570, 2000, Rosario, Argentina.
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Yano K, Okabe C, Fujii K, Kato Y, Ogihara T. Regulation of breast cancer resistance protein and P-glycoprotein by ezrin, radixin and moesin in lung, intestinal and renal cancer cell lines. J Pharm Pharmacol 2020; 72:575-582. [DOI: 10.1111/jphp.13225] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 12/06/2019] [Indexed: 12/19/2022]
Abstract
Abstract
Objectives
Ezrin (Ezr), radixin (Rdx) and moesin (Msn) (ERM) proteins anchor other proteins to the cell membrane, serving to regulate their localization and function. Here, we examined whether ERM proteins functionally regulate breast cancer resistance protein (BCRP) and P-glycoprotein in cell lines derived from lung, intestinal and renal cancers.
Methods
ERM proteins were each silenced with appropriate siRNA. BCRP and P-gp functions were evaluated by means of efflux and uptake assays using 7-ethyl-10-hydroxycamptothecin (SN-38) and rhodamine123 (Rho123) as specific substrates, respectively, in non-small cell lung cancer HCC827 cells, intestinal cancer Caco-2 cells and renal cancer Caki-1 cells.
Key findings
In HCC827 cells, the efflux rates of SN-38 and Rho123 were significantly decreased by knockdown of Ezr or Msn, but not Rdx. However, BCRP function was unaffected by Ezr or Rdx knockdown in Caco-2 cells, which do not express Msn. In Caki-1 cells, Rdx knockdown increased the intracellular SN-38 concentration, while knockdown of Ezr or Msn had no effect.
Conclusions
Our findings indicate that regulation of BCRP and P-gp functions by ERM proteins is organ-specific. Thus, if the appropriate ERM protein(s) are functionally suppressed, accumulation of BCRP or P-gp substrates in lung, intestine or kidney cancer tissue might be specifically increased.
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Affiliation(s)
- Kentaro Yano
- Laboratory of Biopharmaceutics, Department of Pharmacology, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan
| | - Chiaki Okabe
- Laboratory of Biopharmaceutics, Department of Pharmacology, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan
| | - Kenta Fujii
- Laboratory of Biopharmaceutics, Department of Pharmacology, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan
| | - Yuko Kato
- Laboratory of Biopharmaceutics, Department of Pharmacology, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan
| | - Takuo Ogihara
- Laboratory of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan
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Changes in Radixin Expression and Interaction with Efflux Transporters in the Liver of Adjuvant-Induced Arthritic Rats. Inflammation 2019; 43:85-94. [PMID: 31654296 DOI: 10.1007/s10753-019-01097-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Scaffold proteins such as radixin help to modulate the plasma membrane localization and transport activity of the multidrug resistance-associated protein 2 (MRP2/ABCC2) and P-glycoprotein (P-gp/ABCB1) efflux transporters in the liver. We examined changes in radixin expression and interaction with efflux transporters in adjuvant-induced arthritic (AA) rats, an animal model of rheumatoid arthritis, as well as in human liver cancer (HepG2) cells because inflammation affects drug pharmacokinetics via the efflux transporters. The expression levels of radixin and phosphorylated radixin (p-radixin) were measured 24 h after treatment with inflammatory cytokines comprising tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 or sodium nitroprusside (SNP; a nitric oxide donor). The protein levels of radixin, MRP2, and P-gp in the rat liver were next examined. We also investigated whether inflammation affected the formation of complexes between radixin and MRP2 or P-gp. The mRNA and protein levels of radixin in HepG2 cells were significantly decreased by TNF-α treatment, while minimal changes were observed after treatment with IL-1β, IL-6 or SNP. TNF-α also significantly decreased the protein levels of p-radixin, suggesting that TNF-α inhibited the activation of radixin and thereby reduced the activity of the efflux transporters. Complex formation of radixin with MRP2 and P-gp was significantly decreased in AA rats but this was reversed by prednisolone and dexamethasone treatment, indicating that decreased interactions of radixin with MRP2 and P-gp likely occur during liver inflammation. These data suggest that liver inflammation reduces radixin function by decreasing its interactions with MRP2 and P-gp.
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Yano K, Tomono T, Ogihara T. Advances in Studies of P-Glycoprotein and Its Expression Regulators. Biol Pharm Bull 2018; 41:11-19. [PMID: 29311472 DOI: 10.1248/bpb.b17-00725] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This review deals with recent advances in studies on P-glycoprotein (P-gp) and its expression regulators, focusing especially on our own research. Firstly, we describe findings demonstrating that the distribution of P-gp along the small intestine is heterogeneous, which explains why orally administered P-gp substrate drugs often show bimodal changes of plasma concentration. Secondly, we discuss the post-translational regulation of P-gp localization and function by the scaffold proteins ezrin, radixin and moesin (ERM proteins), together with recent reports indicating that tissue-specific differences in regulation by ERM proteins in normal tissues might be retained in corresponding cancerous tissues. Thirdly, we review evidence that P-gp activity is enhanced in the process of epithelial-to-mesenchymal transition (EMT), which is associated with cancer progression, without any increase in expression of P-gp mRNA. Finally, we describe two examples in which P-gp critically influences the brain distribution of drugs, i.e., oseltamivir, where low levels of P-gp associated with early development allow oseltamivir to enter the brain, potentially resulting in neuropsychiatric side effects in children, and cilnidipine, where impairment of P-gp function in ischemia allows cilnidipine to enter the ischemic brain, where it exerts a neuroprotective action.
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Affiliation(s)
- Kentaro Yano
- Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Takumi Tomono
- Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare
| | - Takuo Ogihara
- Faculty of Pharmacy, Takasaki University of Health and Welfare.,Graduate School of Pharmaceutical Sciences, Takasaki University of Health and Welfare
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Fu Y, Yu W, Cai H, Lu A. Forecast of actin-binding proteins as the oncotarget in osteosarcoma - a review of mechanism, diagnosis and therapy. Onco Targets Ther 2018; 11:1553-1561. [PMID: 29593421 PMCID: PMC5865567 DOI: 10.2147/ott.s159894] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Osteosarcoma (OS) is the most common bone malignant tumor with a high rate of lung metastasis and principally emerges in children and adolescents. Although neoadjuvant chemotherapy is widely used around the world, a high rate of chemoresistance occurs and frequently generates a poor prognosis. Therefore, finding a new appropriate prognostic marker for OS is a valuable research direction, which will give patients a better chance to receive proper therapy. Actin-binding proteins (ABPs) are a group of proteins that interact with actin cytoskeleton and play a crucial role in the regulation of the cell motility and morphology in eukaryotes. Meanwhile, ABPs also act as a bridge between the cytomembrane and nucleus, which transmit the outside-in and inside-out signals in cytoplasm. Furthermore, ABPs alter the dynamic structure of actin and regulate the invasion and metastasis of cancer. Hence, ABPs have a wide application in predicting the prognosis, and may be new targets, in tumor therapy. This review focuses on a series of ABPs and discusses their modulatory functions. It provides a new insight into the classification of ABPs’ functions in the process of invasion and metastasis in OS and illuminates the potential ability in predicting the prognosis of OS patients.
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Affiliation(s)
- Yucheng Fu
- Department of Surgical Intensive Care Unit, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People's Republic of China
| | - Wei Yu
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People's Republic of China
| | - Hongliu Cai
- Department of Surgical Intensive Care Unit, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People's Republic of China
| | - Anwei Lu
- Department of Surgical Intensive Care Unit, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People's Republic of China
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12
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O’Sullivan F, Keenan J, Aherne S, O’Neill F, Clarke C, Henry M, Meleady P, Breen L, Barron N, Clynes M, Horgan K, Doolan P, Murphy R. Parallel mRNA, proteomics and miRNA expression analysis in cell line models of the intestine. World J Gastroenterol 2017; 23:7369-7386. [PMID: 29151691 PMCID: PMC5685843 DOI: 10.3748/wjg.v23.i41.7369] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/07/2017] [Accepted: 08/08/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To identify miRNA-regulated proteins differentially expressed between Caco2 and HT-29: two principal cell line models of the intestine. METHODS Exponentially growing Caco-2 and HT-29 cells were harvested and prepared for mRNA, miRNA and proteomic profiling. mRNA microarray profiling analysis was carried out using the Affymetrix GeneChip Human Gene 1.0 ST array. miRNA microarray profiling analysis was carried out using the Affymetrix Genechip miRNA 3.0 array. Quantitative Label-free LC-MS/MS proteomic analysis was performed using a Dionex Ultimate 3000 RSLCnano system coupled to a hybrid linear ion trap/Orbitrap mass spectrometer. Peptide identities were validated in Proteome Discoverer 2.1 and were subsequently imported into Progenesis QI software for further analysis. Hierarchical cluster analysis for all three parallel datasets (miRNA, proteomics, mRNA) was conducted in the R software environment using the Euclidean distance measure and Ward's clustering algorithm. The prediction of miRNA and oppositely correlated protein/mRNA interactions was performed using TargetScan 6.1. GO biological process, molecular function and cellular component enrichment analysis was carried out for the DE miRNA, protein and mRNA lists via the Pathway Studio 11.3 Web interface using their Mammalian database. RESULTS Differential expression (DE) profiling comparing the intestinal cell lines HT-29 and Caco-2 identified 1795 Genes, 168 Proteins and 160 miRNAs as DE between the two cell lines. At the gene level, 1084 genes were upregulated and 711 were downregulated in the Caco-2 cell line relative to the HT-29 cell line. At the protein level, 57 proteins were found to be upregulated and 111 downregulated in the Caco-2 cell line relative to the HT-29 cell line. Finally, at the miRNAs level, 104 were upregulated and 56 downregulated in the Caco-2 cell line relative to the HT-29 cell line. Gene ontology (GO) analysis of the DE mRNA identified cell adhesion, migration and ECM organization, cellular lipid and cholesterol metabolic processes, small molecule transport and a range of responses to external stimuli, while similar analysis of the DE protein list identified gene expression/transcription, epigenetic mechanisms, DNA replication, differentiation and translation ontology categories. The DE protein and gene lists were found to share 15 biological processes including for example epithelial cell differentiation [P value ≤ 1.81613E-08 (protein list); P ≤ 0.000434311 (gene list)] and actin filament bundle assembly [P value ≤ 0.001582797 (protein list); P ≤ 0.002733714 (gene list)]. Analysis was conducted on the three data streams acquired in parallel to identify targets undergoing potential miRNA translational repression identified 34 proteins, whose respective mRNAs were detected but no change in expression was observed. Of these 34 proteins, 27 proteins downregulated in the Caco-2 cell line relative to the HT-29 cell line and predicted to be targeted by 19 unique anti-correlated/upregulated microRNAs and 7 proteins upregulated in the Caco-2 cell line relative to the HT-29 cell line and predicted to be targeted by 15 unique anti-correlated/downregulated microRNAs. CONCLUSION This first study providing "tri-omics" analysis of the principal intestinal cell line models Caco-2 and HT-29 has identified 34 proteins potentially undergoing miRNA translational repression.
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Affiliation(s)
- Finbarr O’Sullivan
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Joanne Keenan
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Sinead Aherne
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Fiona O’Neill
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Colin Clarke
- National Institute for Bioprocessing Research & Training, Blackrock, Dublin A94 X099, Ireland
| | - Michael Henry
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Paula Meleady
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Laura Breen
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Niall Barron
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | - Martin Clynes
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
| | | | - Padraig Doolan
- National Institute for Cellular Biotechnology, Dublin City University, Dublin D09 W6Y4, Ireland
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13
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Okamoto CT. Regulation of Transporters and Channels by Membrane-Trafficking Complexes in Epithelial Cells. Cold Spring Harb Perspect Biol 2017; 9:a027839. [PMID: 28246186 PMCID: PMC5666629 DOI: 10.1101/cshperspect.a027839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The vectorial secretion and absorption of fluid and solutes by epithelial cells is dependent on the polarized expression of membrane solute transporters and channels at the apical and basolateral membranes. The establishment and maintenance of this polarized expression of transporters and channels are affected by divers protein-trafficking complexes. Moreover, regulation of the magnitude of transport is often under control of physiological stimuli, again through the interaction of transporters and channels with protein-trafficking complexes. This review highlights the value in utilizing transporters and channels as cargo to characterize core trafficking machinery by which epithelial cells establish and maintain their polarized expression, and how this machinery regulates fluid and solute transport in response to physiological stimuli.
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Affiliation(s)
- Curtis T Okamoto
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089-9121
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14
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Pokharel D, Roseblade A, Oenarto V, Lu JF, Bebawy M. Proteins regulating the intercellular transfer and function of P-glycoprotein in multidrug-resistant cancer. Ecancermedicalscience 2017; 11:768. [PMID: 29062386 PMCID: PMC5636210 DOI: 10.3332/ecancer.2017.768] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Indexed: 12/15/2022] Open
Abstract
Chemotherapy is an essential part of anticancer treatment. However, the overexpression of P-glycoprotein (P-gp) and the subsequent emergence of multidrug resistance (MDR) hampers successful treatment clinically. P-gp is a multidrug efflux transporter that functions to protect cells from xenobiotics by exporting them out from the plasma membrane to the extracellular space. P-gp inhibitors have been developed in an attempt to overcome P-gp-mediated MDR; however, lack of specificity and dose limiting toxicity have limited their effectiveness clinically. Recent studies report on accessory proteins that either directly or indirectly regulate P-gp expression and function and which are necessary for the establishment of the functional phenotype in cancer cells. This review discusses the role of these proteins, some of which have been recently proposed to comprise an interactive complex, and discusses their contribution towards MDR. We also discuss the role of other pathways and proteins in regulating P-gp expression in cells. The potential for these proteins as novel therapeutic targets provides new opportunities to circumvent MDR clinically.
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Affiliation(s)
- Deep Pokharel
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Ariane Roseblade
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Vici Oenarto
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Jamie F Lu
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Mary Bebawy
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia.,Laboratory of Cancer Cell Biology and Therapeutics, The University of Technology Sydney, Sydney, NSW 2007, Australia
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15
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Kawaguchi K, Yoshida S, Hatano R, Asano S. Pathophysiological Roles of Ezrin/Radixin/Moesin Proteins. Biol Pharm Bull 2017; 40:381-390. [PMID: 28381792 DOI: 10.1248/bpb.b16-01011] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ezrin/radixin/moesin (ERM) proteins function as general cross-linkers between plasma membrane proteins and the actin cytoskeleton and are involved in the functional expression of membrane proteins on the cell surface. They also integrate Rho guanosine 5'-triphosphatase (GTPase) signaling to regulate cytoskeletal organization by sequestering Rho-related proteins. They act as protein kinase A (PKA)-anchoring proteins and sequester PKA close to its target proteins for their effective phosphorylation and functional regulation. Therefore, ERM proteins seem to play important roles in the membrane transport of electrolytes by ion channels and transporters. In this review, we focus on the pathophysiological roles of ERM proteins in in vivo studies and introduce the phenotypes of their knockout and knockdown mice.
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Affiliation(s)
- Kotoku Kawaguchi
- Department of Molecular Physiology, College of Pharmaceutical Sciences, Ritsumeikan University
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16
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Jin G, Li Y, Zhu Y, Du L, Yan J, Yang Q. SMS regulates the expression and function of P-gp and MRP2 in Caco-2 cells. Cell Biol Toxicol 2016; 32:483-497. [PMID: 27394416 DOI: 10.1007/s10565-016-9348-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 06/28/2016] [Indexed: 02/03/2023]
Abstract
Sphingomyelin synthase (SMS) has two isoforms of SMS1 and SMS2, the last enzyme involved in the biosynthesis of sphingomyelin (SM), and has impact on the expression of membrane proteins. In the present study, we explored the potential effects of SMS on drug transporters, a special family of membrane proteins in human intestinal epithelial Caco-2 cells. The specific knockdown of SMS1 or SMS2 with siRNA in Caco-2 cells substantially decreased the expression and function of P-glycoprotein (P-gp) and multidrug resistance protein 2 (MRP2) rather than other drug transporters MRP1, MRP3, PEPT1, OATP2B1, and BCRP. In the SMS1 stable overexpressed Caco-2 cell line, the expression levels of P-gp and MRP2 and transcription factor pregnane X receptor (PXR) were upregulated and the phosphorylation levels of signaling pathways janus protein tyrosine kinase 2 (JAK-2) and extracellular signal-regulated kinases (ERK) were also evidently increased; however, the upregulated mRNA expression levels of PXR, P-gp, and MRP2 were diminished by inhibiting the phosphorylation of ERK and JAK-2. Furthermore, the SMS1 overexpression in Caco-2 cells altered the expression levels of ERM proteins ezrin and moesin, which are closely connected to the function of drug transporters. In conclusion, we herein demonstrate for the first time that in Caco-2 cells SMS regulates the expression and function of drug transporters P-gp and MRP2, and their regulator PXR is mediated by phosphorylated ERK and JAK-2 signaling pathways.
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Affiliation(s)
- Guiying Jin
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Songhu Road 2005, Shanghai, 200438, China
| | - Yang Li
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Songhu Road 2005, Shanghai, 200438, China
| | - Yuwen Zhu
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Songhu Road 2005, Shanghai, 200438, China
| | - Lisha Du
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Songhu Road 2005, Shanghai, 200438, China
| | - Junkai Yan
- Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Qing Yang
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Songhu Road 2005, Shanghai, 200438, China. .,Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China. .,Shanghai Engineering Research Center of Industrial Microorganisms, Songhu Road 2005, Shanghai, 200438, China.
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17
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Walsh DR, Nolin TD, Friedman PA. Drug Transporters and Na+/H+ Exchange Regulatory Factor PSD-95/Drosophila Discs Large/ZO-1 Proteins. Pharmacol Rev 2016; 67:656-80. [PMID: 26092975 DOI: 10.1124/pr.115.010728] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Drug transporters govern the absorption, distribution, and elimination of pharmacologically active compounds. Members of the solute carrier and ATP binding-cassette drug transporter family mediate cellular drug uptake and efflux processes, thereby coordinating the vectorial movement of drugs across epithelial barriers. To exert their physiologic and pharmacological function in polarized epithelia, drug transporters must be targeted and stabilized to appropriate regions of the cell membrane (i.e., apical versus basolateral). Despite the critical importance of drug transporter membrane targeting, the mechanisms that underlie these processes are largely unknown. Several clinically significant drug transporters possess a recognition sequence that binds to PSD-95/Drosophila discs large/ZO-1 (PDZ) proteins. PDZ proteins, such as the Na(+)/H(+) exchanger regulatory factor (NHERF) family, act to stabilize and organize membrane targeting of multiple transmembrane proteins, including many clinically relevant drug transporters. These PDZ proteins are normally abundant at apical membranes, where they tether membrane-delimited transporters. NHERF expression is particularly high at the apical membrane in polarized tissue such as intestinal, hepatic, and renal epithelia, tissues important to drug disposition. Several recent studies have highlighted NHERF proteins as determinants of drug transporter function secondary to their role in controlling membrane abundance and localization. Mounting evidence strongly suggests that NHERF proteins may have clinically significant roles in pharmacokinetics and pharmacodynamics of several pharmacologically active compounds and may affect drug action in cancer and chronic kidney disease. For these reasons, NHERF proteins represent a novel class of post-translational mediators of drug transport and novel targets for new drug development.
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Affiliation(s)
- Dustin R Walsh
- Laboratory for G Protein-Coupled Receptor Biology, Department of Pharmacology and Chemical Biology, and Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (P.A.F.); and Center for Clinical Pharmaceutical Sciences, Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (D.R.W., T.D.N.)
| | - Thomas D Nolin
- Laboratory for G Protein-Coupled Receptor Biology, Department of Pharmacology and Chemical Biology, and Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (P.A.F.); and Center for Clinical Pharmaceutical Sciences, Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (D.R.W., T.D.N.)
| | - Peter A Friedman
- Laboratory for G Protein-Coupled Receptor Biology, Department of Pharmacology and Chemical Biology, and Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (P.A.F.); and Center for Clinical Pharmaceutical Sciences, Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (D.R.W., T.D.N.)
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18
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Chai J, Cai SY, Liu X, Lian W, Chen S, Zhang L, Feng X, Cheng Y, He X, He Y, Chen L, Wang R, Wang H, Boyer JL, Chen W. Canalicular membrane MRP2/ABCC2 internalization is determined by Ezrin Thr567 phosphorylation in human obstructive cholestasis. J Hepatol 2015; 63. [PMID: 26212029 PMCID: PMC4686151 DOI: 10.1016/j.jhep.2015.07.016] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Multidrug resistance-associated protein 2 (MRP2) excretes conjugated organic anions including bilirubin and bile acids. Malfunction of MRP2 leads to jaundice in patients. Studies in rodents indicate that Radixin plays a critical role in determining Mrp2 canalicular membrane expression. However, it is not known how human hepatic MRP2 expression is regulated in cholestasis. METHODS We assessed liver MRP2 expression in patients with obstructive cholestasis caused by gallstone blockage of bile ducts, and investigated the regulatory mechanism in HepG2 cells. RESULTS Western blot detected that liver MRP2 protein expression in obstructive cholestatic patients (n=30) was significantly reduced to 25% of the non-cholestatic controls (n=23). Immunoprecipitation identified Ezrin but not Radixin associating with MRP2 in human livers, and the increased amount of phospho-Ezrin Thr567 was positively correlated with the amount of co-precipitated MRP2 in cholestatic livers, whereas Ezrin and Radixin total protein levels were unchanged in cholestasis. Further detailed studies indicate that Ezrin Thr567 phosphorylation plays an important role in MRP2 internalization in HepG2 cells. Since increased expression of PKCα, δ and ε were detected in these cholestatic livers, we further confirmed that these PKCs stimulated Ezrin phosphorylation and reduced MRP2 membrane expression in HepG2 cells. Finally, we identified GP78 as the key ubiquitin ligase E3 involved in MRP2 proteasome degradation. CONCLUSIONS Activation of liver PKCs during cholestasis leads to Ezrin Thr567 phosphorylation resulting in MRP2 internalization and degradation where ubiquitin ligase E3 GP78 is involved. This process provides a mechanistic explanation for jaundice seen in patients with obstructive cholestasis.
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Affiliation(s)
- Jin Chai
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Shi-Ying Cai
- Liver Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Xiaocong Liu
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Wei Lian
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Sheng Chen
- Department of Pediatrics, Third Military Medical University, Chongqing 400038, P.R. China
| | - Liangjun Zhang
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Xinchan Feng
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Ying Cheng
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Xiaochong He
- School of Nursing, Third Military Medical University, Chongqing 400038, P.R. China
| | - Yu He
- Institute of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Lei Chen
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Rongquan Wang
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, P.R. China
| | - Huaizhi Wang
- Institute of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China.
| | - James L. Boyer
- Liver Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Wensheng Chen
- Department of Gastroenterology, Third Military Medical University, Chongqing 400038, PR China.
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Kobori T, Harada S, Nakamoto K, Tokuyama S. Role of Scaffold Proteins in Functional Alteration of Small Intestinal P-glycoprotein by Anti-cancer Drugs. YAKUGAKU ZASSHI 2015; 135:687-95. [DOI: 10.1248/yakushi.14-00234-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Takuro Kobori
- Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University
| | - Shinichi Harada
- Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University
| | - Kazuo Nakamoto
- Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University
| | - Shogo Tokuyama
- Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University
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20
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Kobori T, Harada S, Nakamoto K, Tokuyama S. [Effect of repeated oral treatment with etoposide on the expression of intestinal P-glycoprotein and oral morphine analgesia]. YAKUGAKU ZASSHI 2015; 134:689-99. [PMID: 24882643 DOI: 10.1248/yakushi.13-00255-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Currently, the World Health Organization recommends oral administration of opioid analgesics for patients with cancer to treat cancer-related pain from the initial stage of treatment. Furthermore, many anticancer drugs have been newly-developed and approved as oral form. Because of this trend, the chances of drug-drug interactions between anticancer drugs and opioid analgesics during absorption process from the intestine are likely to increase. To investigate these possible drug-drug interactions, we have focused on intestinal P-glycoprotein (P-gp) which regulates the absorption of various substrate drugs administered orally. Previously, we have found that repeated oral treatment with etoposide (ETP), an anticancer drug, attenuates analgesia of oral morphine, a substrate drug for P-gp, by increasing the expression and activity of intestinal P-gp. However, the mechanism by which ETP treatment increases the intestinal P-gp expression and decreases oral morphine analgesia remains unclear. RhoA, a small G-protein, and ROCK, an effector of RhoA, pathway has been attracted attention with regard to their involvement in the regulatory mechanism of the expression and activity of P-gp. Interestingly, this pathway is activated in response to various signaling induced by some anticancer drugs. Furthermore, it has been reported that ezrin/radixin/moesin (ERM) play a key role in the plasma membrane localization of P-gp, and that RhoA/ROCK pathway regulates the activation process of ERM. This review article introduces the result of our previous research as well as recent findings on the involvement of ERM via activation of RhoA/ROCK in the increased expression of intestinal P-gp and decreased oral morphine analgesia induced by repeated oral treatment with ETP.
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Affiliation(s)
- Takuro Kobori
- Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University
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21
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Silva R, Vilas-Boas V, Carmo H, Dinis-Oliveira RJ, Carvalho F, de Lourdes Bastos M, Remião F. Modulation of P-glycoprotein efflux pump: induction and activation as a therapeutic strategy. Pharmacol Ther 2014; 149:1-123. [PMID: 25435018 DOI: 10.1016/j.pharmthera.2014.11.013] [Citation(s) in RCA: 243] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 11/19/2014] [Indexed: 01/03/2023]
Abstract
P-glycoprotein (P-gp) is an ATP-dependent efflux pump encoded by the MDR1 gene in humans, known to mediate multidrug resistance of neoplastic cells to cancer therapy. For several decades, P-gp inhibition has drawn many significant research efforts in an attempt to overcome this phenomenon. However, P-gp is also constitutively expressed in normal human epithelial tissues and, due to its broad substrate specificity, to its cellular polarized expression in many excretory and barrier tissues, and to its great efflux capacity, it can play a crucial role in limiting the absorption and distribution of harmful xenobiotics, by decreasing their intracellular accumulation. Such a defense mechanism can be of particular relevance at the intestinal level, by significantly reducing the intestinal absorption of the xenobiotic and, consequently, avoiding its access to the target organs. In this review, the current knowledge on this important efflux pump is summarized, and a new focus is brought on the therapeutic interest of inducing and/or activating P-gp for limiting the toxicity caused by its substrates. Several in vivo and in vitro studies validating the use of such a therapeutic strategy are discussed. An extensive literature search for reported P-gp inducers/activators and for the experimental models used in their characterization was conducted. Those studies demonstrate that effective antidotal pathways can be achieved by efficiently promoting the P-gp-mediated efflux of deleterious xenobiotics, resulting in a significant reduction in their intracellular levels and, consequently, in a significant reduction of their toxicity.
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Affiliation(s)
- Renata Silva
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Vânia Vilas-Boas
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Helena Carmo
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Ricardo Jorge Dinis-Oliveira
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; INFACTS - Institute of Research and Advanced Training in Health Sciences and Technologies, Department of Sciences, Advanced Institute of Health Sciences - North (ISCS-N), CESPU, CRL, Gandra, Portugal; Department of Legal Medicine and Forensic Sciences, Faculty of Medicine, University of Porto, Porto, Portugal.
| | - Félix Carvalho
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Maria de Lourdes Bastos
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Fernando Remião
- UCIBIO-REQUIMTE, Laboratory of Toxicology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
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The Role of the Actin Cytoskeleton and Lipid Rafts in the Localization and Function of the ABCC1 Transporter. ACTA ACUST UNITED AC 2014. [DOI: 10.1155/2014/105898] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
ATP-binding cassette (ABC) transporters are known to be important factors in multidrug resistance of tumor cells. Lipid rafts have been implicated in their localization in the plasma membrane, where they function as drug efflux pumps. This specific localization in rafts may support the activity of ABC/Abc transporters. This raises questions regarding the nature and composition of the lipid rafts that harbor ABC/Abc transporters and the dependence of ABC/Abc transporters—concerning their localization and activity—on lipid raft constituents. Here we review our work of the past 10 years aimed at evaluating whether ABC/Abc transporters are dependent on a particular membrane environment for their function. What is the nature of this membrane environment and which of the lipid raft constituents are important for this dependency? It turns out that cortical actin is of major importance for stabilizing the localization and function of the ABC/Abc transporter, provided it is localized in an actin-dependent subtype of lipid rafts, as is the case for human ABCC1/multidrug resistance-related protein 1 (MRP1) and rodent Abcc1/Mrp1 but not human ABCB1/P-glycoprotein (PGP). On the other hand, sphingolipids do not appear to be modulators of ABCC1/MRP1 (or Abcc1/Mrp1), even though they are coregulated during drug resistance development.
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Kobori T, Harada S, Nakamoto K, Tokuyama S. Involvement of PtdIns(4,5)P2 in the regulatory mechanism of small intestinal P-glycoprotein expression. J Pharm Sci 2013; 103:743-51. [PMID: 24311454 DOI: 10.1002/jps.23811] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/07/2013] [Accepted: 11/18/2013] [Indexed: 11/11/2022]
Abstract
Previously, we reported that repeated oral administration of etoposide (ETP) activates the ezrin/radixin/moesin (ERM) scaffold proteins for P-glycoprotein (P-gp) via Ras homolog gene family member A (RhoA)/Rho-associated coiled-coil containing protein kinase (ROCK) signaling, leading to increased ileal P-gp expression. Recent studies indicate that phosphatidyl inositol 4,5-bisphosphate [PtdIns(4,5)P2] regulates the plasma-membrane localization of certain proteins, and its synthase, the type I phosphatidyl inositol 4-phosphate 5-kinase (PI4P5K), is largely controlled by RhoA/ROCK. Here, we examined whether PtdIns(4,5)P2 and PI4P5K are involved in the increased expression of ileal P-gp following the ERM activation by ETP treatment. Male ddY mice (4-week-old) were treated with ETP (10 mg/kg/day, per os, p.o.) for 5 days. Protein-expression levels were measured by either western blot or dot blot analysis and molecular interactions were assessed using immunoprecipitation assays. ETP treatment significantly increased PI4P5K, ERM, and P-gp expression in the ileal membrane. This effect was suppressed following the coadministration of ETP with rosuvastatin (a RhoA inhibitor) or fasudil (a ROCK inhibitor). Notably, the PtdIns(4,5)P2 expression in the ileal membrane, as well as both P-gp and ERM levels coimmunoprecipitated with anti-PtdIns(4,5)P2 antibody, were increased by ETP treatment. PtdIns(4,5)P2 and PI4P5K may contribute to the increase in ileal P-gp expression observed following the ETP treatment, possibly through ERM activation via the RhoA/ROCK pathway.
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Affiliation(s)
- Takuro Kobori
- Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kobe Gakuin University, Kobe, Japan
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Nakano T, Sekine S, Ito K, Horie T. Ezrin regulates the expression of Mrp2/Abcc2 and Mdr1/Abcb1 along the rat small intestinal tract. Am J Physiol Gastrointest Liver Physiol 2013; 305:G807-17. [PMID: 24091598 DOI: 10.1152/ajpgi.00187.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Multidrug resistance-associated protein 2 (MRP2)/ATP-binding cassette protein C2 (ABCC2) and multidrug resistance protein 1 (MDR1)/ABCB1 are well-known efflux transporters located on the brush border membrane of the small intestinal epithelia, where they limit the absorption of a broad range of substrates. The expression patterns of MRP2/ABCC2 and MDR1/ABCB1 along the small intestinal tract are tightly regulated. Several reports have demonstrated the participation of ERM (ezrin/radixin/moesin) proteins in the posttranslational modulation of MRP2/ABCC2 and MDR1/ABCB1, especially with regard to their membrane localization. The present study focused on the in vivo expression profiles of MRP2/ABCC2, MDR1/ABCB1, ezrin, and phosphorylated ezrin to further elucidate the relationship between the efflux transporters and the ERM proteins. The current results showed good correlation between the phosphorylation status of ezrin and Mrp2/Abcc2 expression along the gastrointestinal tract of rats and between the expression profiles of both ezrin and Mdr1/Abcb1 in the small intestine. We also demonstrated the involvement of conventional protein kinase C isoforms in the regulation of ezrin phosphorylation. Furthermore, experiments conducted with wild-type (WT) ezrin and a T567A (Ala substituted Thr) dephosphorylated mutant showed a decrease in membrane surface-localized and total expressed MRP2/ABCC2 in T567A-expressing vs. WT ezrin-expressing Caco-2 cells. In contrast, T567A- and WT-expressing cells both showed an increase in membrane surface-localized and total expressed MDR1/ABCB1. These findings suggest that the phosphorylation status and the expression profile of ezrin differentially direct MRP2/ABCC2 and MDR1/ABCB1 expression, respectively, along the small intestinal tract.
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Affiliation(s)
- Takafumi Nakano
- Faculty of Pharmaceutical Sciences, Teikyo Heisei University, 4-21-2 Nakano, Nakano-ku, Tokyo 164-8530, Japan.
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Abstract
Bile is a unique and vital aqueous secretion of the liver that is formed by the hepatocyte and modified down stream by absorptive and secretory properties of the bile duct epithelium. Approximately 5% of bile consists of organic and inorganic solutes of considerable complexity. The bile-secretory unit consists of a canalicular network which is formed by the apical membrane of adjacent hepatocytes and sealed by tight junctions. The bile canaliculi (∼1 μm in diameter) conduct the flow of bile countercurrent to the direction of portal blood flow and connect with the canal of Hering and bile ducts which progressively increase in diameter and complexity prior to the entry of bile into the gallbladder, common bile duct, and intestine. Canalicular bile secretion is determined by both bile salt-dependent and independent transport systems which are localized at the apical membrane of the hepatocyte and largely consist of a series of adenosine triphosphate-binding cassette transport proteins that function as export pumps for bile salts and other organic solutes. These transporters create osmotic gradients within the bile canalicular lumen that provide the driving force for movement of fluid into the lumen via aquaporins. Species vary with respect to the relative amounts of bile salt-dependent and independent canalicular flow and cholangiocyte secretion which is highly regulated by hormones, second messengers, and signal transduction pathways. Most determinants of bile secretion are now characterized at the molecular level in animal models and in man. Genetic mutations serve to illuminate many of their functions.
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Affiliation(s)
- James L Boyer
- Department of Medicine and Liver Center, Yale University School of Medicine, New Haven, Connecticut, USA.
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Kobori T, Harada S, Nakamoto K, Tokuyama S. Time-Dependent Changes in the Activation of RhoA/ROCK and ERM/p-ERM in the Increased Expression of Intestinal P-Glycoprotein by Repeated Oral Treatment with Etoposide. J Pharm Sci 2013; 102:1670-82. [DOI: 10.1002/jps.23503] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 01/30/2013] [Accepted: 02/19/2013] [Indexed: 11/12/2022]
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Kobori T, Harada S, Nakamoto K, Tokuyama S. Activation of ERM-Family Proteins via RhoA-ROCK Signaling Increases Intestinal P-gp Expression and Leads to Attenuation of Oral Morphine Analgesia. J Pharm Sci 2013; 102:1095-105. [DOI: 10.1002/jps.23441] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 11/27/2012] [Accepted: 12/14/2012] [Indexed: 11/08/2022]
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Emi Y, Yasuda Y, Sakaguchi M. A cis-acting five-amino-acid motif controls targeting of ABCC2 to the apical plasma membrane domain. J Cell Sci 2012; 125:3133-43. [PMID: 22454528 DOI: 10.1242/jcs.099549] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
ATP-binding cassette transporter isoform C2 (ABCC2) is exclusively targeted to the apical plasma membrane of polarized cells. Although apical localization of ABCC2 in hepatocytes is crucial for the biliary excretion of a variety of metabolites, the mechanism regulating its apical targeting is poorly understood. In the present study, an apical targeting signal was identified in the first cytoplasmic loop domain (CLD1) of ABCC2 in HepG2 cells. Overexpression of CLD1 significantly disturbed the apical targeting of FLAG-ABCC2 in a competitive manner, suggesting the presence of a saturable sorting machinery in HepG2 cells. Next, deletion analysis identified a potential targeting sequence within a 20-amino-acid long peptide (aa 272-291) of CLD1. Alanine scanning mutagenesis of this region in full-length ABCC2 further narrowed down the apical targeting determinant to five amino acids, S(283)QDAL(287). Of these, S(283) and L(287) were found to be conserved among vertebrate ABCC2 orthologs. Site-directed mutagenesis showed that both S(283) and L(287) were crucial for the targeting specificity of ABCC2. Introducing this apical targeting sequence into the corresponding region of ABCC1, an exclusively basolateral protein, caused the hybrid ABCC1 to partially localize in the apical membrane. Thus, the CLD1 of ABCC2 contains a novel apical sorting determinant, and a saturable sorting machinery is present in polarized HepG2 cells.
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Affiliation(s)
- Yoshikazu Emi
- Graduate School of Life Science, University of Hyogo, Harima Science Park City, Hyogo, Japan.
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He XJ, Wang WR, Zhang Y, Yang Q. The effect of radixin knockdown on the expression and efflux function of MRP2 in SGC-7901 cells. Eur J Pharm Sci 2012; 46:426-34. [PMID: 22469515 DOI: 10.1016/j.ejps.2012.03.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 03/12/2012] [Accepted: 03/18/2012] [Indexed: 12/18/2022]
Abstract
Multidrug resistance-associated protein 2 (MRP2, ABCC2) is the second member of the MRP transporter family and functions physiologically as an organic anion transporter. Earlier studies have confirmed that radixin, which is a member of the ERM (ezrin/radixin/moesin) family, modulates MRP2 localization at the canalicular membrane in hepatocytes. The relationship between radixin and MRP2 - particularly, the effect of radixin on the expression and function of MRP2 in cells or tissues that co-express all three ERM proteins - has not been well studied. To examine the role of radixin in the expression and function of MRP2 and other MRPs, we chose human gastric carcinoma SGC-7901 cells that express all three ERM proteins rather than hepatocytes, which predominantly express radixin. Radixin stable knockdown SGC-7901 cells, which were constructed by RNAi, exhibited no compensatory up-regulation of ezrin or moesin. The mRNA expression profiles of MRPs in the radixin knockdown cells were primarily evaluated by RT-PCR. Real time quantitative RT-PCR and western blot analysis revealed that the radixin deficiency caused the mRNA and protein expression levels of MRP2 to be reduced by about 50%, respectively. Accordingly, efflux and MTT assays showed that the radixin knockdown cells exhibited lower efflux ability with respect to calcein but no significant change in cell viability. In conclusion, among the MRP1-6 family members, radixin selectively modulates the expression and function of MRP2 in a system co-expressing all three ERM proteins.
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Affiliation(s)
- Xiao-Jie He
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China.
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Kano T, Wada S, Morimoto K, Kato Y, Ogihara T. Effect of Knockdown of Ezrin, Radixin, and Moesin on P-Glycoprotein Function in HepG2 Cells. J Pharm Sci 2011; 100:5308-14. [DOI: 10.1002/jps.22718] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 06/07/2011] [Accepted: 07/12/2011] [Indexed: 11/05/2022]
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Agbor TA, Demma ZC, Mumy KL, Bien JD, McCormick BA. The ERM protein, ezrin, regulates neutrophil transmigration by modulating the apical localization of MRP2 in response to the SipA effector protein during Salmonella Typhimurium infection. Cell Microbiol 2011; 13:2007-21. [PMID: 21899702 DOI: 10.1111/j.1462-5822.2011.01693.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In human disease induced by Salmonella enterica serovar Typhimurium (S. Typhimurium), transepithelial migration of neutrophils rapidly follows attachment of the bacteria to the epithelial apical membrane. We have previously shown that during S. Typhimurium infection the multidrug resistance-associated protein 2 (MRP2) is highly expressed at the apical surface of the intestinal epithelia, and that it functions as an efflux pump for the potent neutrophil chemoattractant hepoxilin A(3) . However, the molecular mechanisms regulating its apical localization during active states of inflammation remain unknown. Thus, our objective was to determine the mechanistic basis for the translocation of MRP2 to the apical surface of intestinal epithelial cells during S. Typhimurium infection. We show that suppression of ezrin, through either RNAi or truncation of the C-terminus, results not only in a decrease in S. Typhimurium-induced neutrophil transmigration but also significantly attenuates the apical membrane expression of MRP2 during Salmonella infection. In addition, we determined that S. Typhimurium induces the activation of ezrin via a PKC-α-dependent pathway and that ezrin activation is coupled to apical localization of MRP2. Based on these results we propose that activation of ezrin is required for the apical localization of MRP2 during S. Typhimurium infection.
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Affiliation(s)
- Terence A Agbor
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01655, USA
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The effect of sphingomyelin synthase 2 (SMS2) deficiency on the expression of drug transporters in mouse brain. Biochem Pharmacol 2011; 82:287-94. [DOI: 10.1016/j.bcp.2011.04.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2011] [Revised: 04/17/2011] [Accepted: 04/19/2011] [Indexed: 11/18/2022]
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Saeki J, Sekine S, Horie T. LPS-induced dissociation of multidrug resistance-associated protein 2 (Mrp2) and radixin is associated with Mrp2 selective internalization in rats. Biochem Pharmacol 2011; 81:178-84. [DOI: 10.1016/j.bcp.2010.09.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 09/16/2010] [Accepted: 09/16/2010] [Indexed: 01/17/2023]
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Wang HJ, Zhu JS, Zhang Q, Guo H, Dai YH, Xiong XP. RNAi-mediated silencing of ezrin gene reverses malignant behavior of human gastric cancer cell line SGC-7901. J Dig Dis 2009; 10:258-64. [PMID: 19906104 DOI: 10.1111/j.1751-2980.2009.00394.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To investigate the effects of ezrin targeting gene of RNA interference (RNAi) on human gastric cancer cell line SGC-7901 in vitro. METHODS The highly metastatic human gastric cancer cell line SGC-7901 transfected with a small interfering (siRNA) lentivirus vector was selected for this research study. Expressions of ezrin mRNA and ezrin protein in the SGC-7901 cells were detected using RT-PCR and Western blot. Cell apoptosis was observed using flow cytometry. Transwell invasion and the cell adhesion test were used to verify the effect of RNAi on ezrin expression in the human gastric cancer cell line SGC-7901 in vitro. RESULTS Ezrin gene targeting via a RNAi-mediated lentivirus vector had obvious inhibitory effects on ezrin expression in the human gastric cancer cell line SGC-7901. The results of the RT-PCR show the obvious inhibition of ezrin mRNA expression in Eai and Ebi groups (0.22 +/- 0.01 vs 0.95 +/- 0.04, P < 0.05; 0.31 +/- 0.01 vs. 0.95 +/- 0.04, P < 0.05). Western blot analysis revealed a 72.35 +/- 3.74% reduction of the ezrin protein level after interference with the ezrin targeting gene. Moreover, the inhibition of ezrin expression clearly inhibited SGC-7901 cell migration and invasion, and improved cell adhesion as well as increased sensitivity to camptothecin-induced apoptosis. CONCLUSION Ezrin gene targeting by RNAi can inhibit the metastatic growth and migration of SGC-7901 human gastric cancer cells.
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Affiliation(s)
- Hong Jian Wang
- Department of Gastroenterology, Sixth People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China
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FERM proteins in animal morphogenesis. Curr Opin Genet Dev 2009; 19:357-67. [PMID: 19596566 DOI: 10.1016/j.gde.2009.05.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 05/29/2009] [Indexed: 01/19/2023]
Abstract
Proteins containing a FERM domain are ubiquitous components of the cytocortex of animal cells where they are engaged in structural, transport, and signaling functions. Recent years have seen a wealth of genetic studies in model organisms that explore FERM protein function in development and tissue organization. In addition, mutations in several FERM protein-encoding genes have been associated with human diseases. This review will provide a brief overview of the FERM domain structure and the FERM protein superfamily and then discuss recent advances in our understanding of the mechanism of function and developmental requirement of several FERM proteins including Moesin, Myosin-VIIA, Myosin-XV, Coracle/Band4.1 as well as Yurt and its vertebrate homologs Mosaic Eyes and EPB41L5/YMO1/Limulus.
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Nakano T, Sekine S, Ito K, Horie T. Correlation between apical localization of Abcc2/Mrp2 and phosphorylation status of ezrin in rat intestine. Drug Metab Dispos 2009; 37:1521-7. [PMID: 19339379 DOI: 10.1124/dmd.108.024836] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The multidrug resistance-associated protein 2/ATP-binding cassette transporter family C2 (Mrp2/Abcc2) is an ATP-dependent export pump that mediates the transport of a variety of organic anions. Abcc2 is mainly expressed on the canalicular membrane of hepatocytes and also the brush-border membrane of intestinal epithelial cells. We have previously reported that Abcc2 is rapidly internalized from the canalicular membrane during acute oxidative stress, which induces protein kinase C (PKC) activation in rat liver. However, it has not been elucidated whether PKC is involved in the regulation of Abcc2 localization in other tissues. In this study, we investigated this issue in rat intestinal epithelia. Exposure to thymeleatoxin, a conventional PKC (cPKC) activator, for 20 min reduced the cumulative glutathione S-bimane efflux for 40 min via Abcc2 from 30.3 +/- 2.1 nmol/cm to 18.1 +/- 1.6 nmol/cm. Likewise, the Abcc2 expression in the brush-border membrane of the small intestine was reduced to half that of the control without changing the total amount of Abcc2 present in the homogenate. Immunoprecipitation analysis suggested an interaction between Abcc2 and ezrin, a scaffolding protein that is dominantly expressed in the intestine. Thymeleatoxin treatment decreased the amount of the active form (C-terminally phosphorylated form) of ezrin and the amount of Abcc2 that coimmunoprecipitated with ezrin. These results indicate that cPKC activation diminishes the protein-protein interaction between ezrin and Abcc2. In conclusion, the phosphorylation status of ezrin correlates with the cell surface expression of Abcc2 in the rat small intestine, which may be regulated by cPKC.
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Affiliation(s)
- Takafumi Nakano
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8675, Japan
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