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Intracellular prostaglandin E2 contributes to hypoxia-induced proximal tubular cell death. Sci Rep 2021; 11:7047. [PMID: 33782420 PMCID: PMC8007803 DOI: 10.1038/s41598-021-86219-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 02/22/2021] [Indexed: 12/23/2022] Open
Abstract
Proximal tubular cells (PTC) are particularly vulnerable to hypoxia-induced apoptosis, a relevant factor for kidney disease. We hypothesized here that PTC death under hypoxia is mediated by cyclo-oxygenase (COX-2)-dependent production of prostaglandin E2 (PGE2), which was confirmed in human proximal tubular HK-2 cells because hypoxia (1% O2)-induced apoptosis (i) was prevented by a COX-2 inhibitor and by antagonists of prostaglandin (EP) receptors and (ii) was associated to an increase in intracellular PGE2 (iPGE2) due to hypoxia-inducible factor-1α-dependent transcriptional up-regulation of COX-2. Apoptosis was also prevented by inhibitors of the prostaglandin uptake transporter PGT, which indicated that iPGE2 contributes to hypoxia-induced apoptosis (on the contrary, hypoxia/reoxygenation-induced PTC death was exclusively due to extracellular PGE2). Thus, iPGE2 is a new actor in the pathogenesis of hypoxia-induced tubular injury and PGT might be a new therapeutic target for the prevention of hypoxia-dependent lesions in renal diseases.
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2
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Yago-Ibáñez J, García-Pastor C, Lucio-Cazaña FJ, Fernández-Martínez AB. Retinoic acid receptor-beta prevents cisplatin-induced proximal tubular cell death. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165795. [PMID: 32278009 DOI: 10.1016/j.bbadis.2020.165795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/26/2020] [Accepted: 04/06/2020] [Indexed: 01/14/2023]
Abstract
Cisplatin's toxicity in renal tubular epithelial cells limits the therapeutic efficacy of this antineoplastic drug. In cultured human proximal tubular HK-2 cells (PTC) a prostaglandin uptake transporter (PGT)-dependent increase in intracellular prostaglandin E2 (iPGE2) mediates cisplatin's toxicity (i.e. increased cell death and loss of cell proliferation) so that it is prevented by PGT inhibitors. Here we found in cisplatin-treated PTC that 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), a PGT inhibitor, prevented cisplatin's toxicity but not the increase in iPGE2. Because expression of retinoic acid receptor-β (RAR-β) is dependent on iPGE2 and because RAR-β is a regulator of cell survival and proliferation, we hypothesized that RAR-β might mediate the protective effect of DIDS against cisplatin's toxicity in PTC. Our results confirmed this hypothesis because: i) protection of PTC by DIDS was abolished by RAR-β antagonist LE-135; ii) DIDS increased the expression of RAR-β in PTC and prevented its decrease in cisplatin-treated PTC but not in cisplatin-treated human cervical adenocarcinoma HeLa cells in which DIDS failed to prevent cisplatin's toxicity; iii) while RAR-β expression decreased in cisplatin-treated PTC, RAR-β over-expression prevented cisplatin's toxicity. RAR-β agonist CH55 or RAR pan-agonist all-trans retinoic acid did not prevent cisplatin's toxicity, which suggests that RAR-β does not protect PTC through activation of gene transcription. In conclusion, RAR-β might be a new player in cisplatin-induced proximal tubular injury and the preservation of its expression in proximal tubules through treatment with DIDS might represent a novel strategy in the prevention of cisplatin's nephrotoxicity without compromising cisplatin's chemotherapeutic effect on cancer cells.
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Affiliation(s)
- Julia Yago-Ibáñez
- Departamento de Biología, Universidad Autónoma de Madrid, Madrid, Spain
| | - Coral García-Pastor
- Departamento de Biología de Sistemas, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
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3
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Sato N, Yako Y, Maruyama T, Ishikawa S, Kuromiya K, Tokuoka SM, Kita Y, Fujita Y. The COX-2/PGE 2 pathway suppresses apical elimination of RasV12-transformed cells from epithelia. Commun Biol 2020; 3:132. [PMID: 32188886 PMCID: PMC7080752 DOI: 10.1038/s42003-020-0847-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 02/20/2020] [Indexed: 12/30/2022] Open
Abstract
At the initial stage of carcinogenesis, when RasV12-transformed cells are surrounded by normal epithelial cells, RasV12 cells are apically extruded from epithelia through cell competition with the surrounding normal cells. In this study, we demonstrate that expression of cyclooxygenase (COX)-2 is upregulated in normal cells surrounding RasV12-transformed cells. Addition of COX inhibitor or COX-2-knockout promotes apical extrusion of RasV12 cells. Furthermore, production of Prostaglandin (PG) E2, a downstream prostanoid of COX-2, is elevated in normal cells surrounding RasV12 cells, and addition of PGE2 suppresses apical extrusion of RasV12 cells. In a cell competition mouse model, expression of COX-2 is elevated in pancreatic epithelia harbouring RasV12-exressing cells, and the COX inhibitor ibuprofen promotes apical extrusion of RasV12 cells. Moreover, caerulein-induced chronic inflammation substantially suppresses apical elimination of RasV12 cells. These results indicate that intrinsically or extrinsically mediated inflammation can promote tumour initiation by diminishing cell competition between normal and transformed cells.
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Affiliation(s)
- Nanami Sato
- Division of Molecular Oncology, Institute for Genetic Medicine, Hokkaido University Graduate School of Chemical Sciences and Engineering, Sapporo, Hokkaido, 060-0815, Japan
| | - Yuta Yako
- Division of Molecular Oncology, Institute for Genetic Medicine, Hokkaido University Graduate School of Chemical Sciences and Engineering, Sapporo, Hokkaido, 060-0815, Japan
| | - Takeshi Maruyama
- Division of Molecular Oncology, Institute for Genetic Medicine, Hokkaido University Graduate School of Chemical Sciences and Engineering, Sapporo, Hokkaido, 060-0815, Japan
| | - Susumu Ishikawa
- Division of Molecular Oncology, Institute for Genetic Medicine, Hokkaido University Graduate School of Chemical Sciences and Engineering, Sapporo, Hokkaido, 060-0815, Japan
| | - Keisuke Kuromiya
- Division of Molecular Oncology, Institute for Genetic Medicine, Hokkaido University Graduate School of Chemical Sciences and Engineering, Sapporo, Hokkaido, 060-0815, Japan
| | - Suzumi M Tokuoka
- Department of Lipidomics, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Yoshihiro Kita
- Department of Lipidomics, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
- Life Sciences Core Facility, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Yasuyuki Fujita
- Division of Molecular Oncology, Institute for Genetic Medicine, Hokkaido University Graduate School of Chemical Sciences and Engineering, Sapporo, Hokkaido, 060-0815, Japan.
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4
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Nakanishi T, Ohno Y, Aotani R, Maruyama S, Shimada H, Kamo S, Oshima H, Oshima M, Schuetz JD, Tamai I. A novel role for OATP2A1/SLCO2A1 in a murine model of colon cancer. Sci Rep 2017; 7:16567. [PMID: 29185482 PMCID: PMC5707394 DOI: 10.1038/s41598-017-16738-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 11/16/2017] [Indexed: 11/24/2022] Open
Abstract
Prostaglandin E2 (PGE2) is associated with proliferation and angiogenesis in colorectal tumours. The role of prostaglandin transporter OATP2A1/SLCO2A1 in colon cancer tumorogenesis is unknown. We evaluated mice of various Slco2a1 genotypes in a murine model of colon cancer, the adenomatous polyposis (APC) mutant (Apc∆716/+) model. Median lifespan was significantly extended from 19 weeks in Slco2a1+/+/ApcΔ716/+ mice to 25 weeks in Slco2a1−/−/ApcΔ716/+ mice. Survival was directly related to a reduction in the number of large polyps in the Slco2a1−/−/Apc∆716/+ compared to the Slco2a1+/+/ApcΔ716/+ or Slco2a1+/−/ApcΔ716/+mice. The large polyps from the Slco2a1−/−/Apc∆716/+ mice had significant reductions in microvascular density, consistent with the high expression of Slco2a1 in the tumour-associated vascular endothelial cells. Chemical suppression of OATP2A1 function significantly reduced tube formation and wound-healing activity of PGE2 in human vascular endothelial cells (HUVECs) although the amount of extracellular PGE2 was not affected by an OATP2A1 inhibitor. Further an in vivo model of angiogenesis, showed a significant reduction of haemoglobin content (54.2%) in sponges implanted into Slco2a1−/−, compared to wildtype mice. These studies indicate that OATP2A1 is likely to promote tumorogenesis by PGE2 uptake into the endothelial cells, suggesting that blockade of OATP2A1 is an additional pharmacologic strategy to improve colon cancer outcomes.
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Affiliation(s)
| | | | - Rika Aotani
- Kanazawa University, Kanazawa, 920-1192, Japan
| | | | - Hiroaki Shimada
- Kanazawa University, Kanazawa, 920-1192, Japan.,Faculty of Pharmacy, Kindai University, Higashiosaka, Osaka, Japan
| | | | - Hiroko Oshima
- Cancer Research Institute, Kanazawa University, Kanazawa, Japan
| | - Masanobu Oshima
- Cancer Research Institute, Kanazawa University, Kanazawa, Japan
| | - John D Schuetz
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ikumi Tamai
- Kanazawa University, Kanazawa, 920-1192, Japan
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Madrigal-Martínez A, Fernández-Martínez AB, Lucio Cazaña FJ. Intracrine prostaglandin E 2 pro-tumoral actions in prostate epithelial cells originate from non-canonical pathways. J Cell Physiol 2017; 233:3590-3602. [PMID: 29154474 DOI: 10.1002/jcp.26220] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/29/2017] [Indexed: 12/21/2022]
Abstract
Prostaglandin E2 (PGE2 ) increases cell proliferation and stimulates migratory and angiogenic abilities in prostate cancer cells. However, the effects of PGE2 on non-transformed prostate epithelial cells are unknown, despite the fact that PGE2 overproduction has been found in benign hyperplastic prostates. In the present work we studied the effects of PGE2 in immortalized, non-malignant prostate epithelial RWPE-1 cells and found that PGE2 increased cell proliferation, cell migration, and production of vascular endothelial growth factor-A, and activated in vitro angiogenesis. These actions involved a non-canonic intracrine mechanism in which the actual effector was intracellular PGE2 (iPGE2 ) instead of extracellular PGE2 : inhibition of the prostaglandin uptake transporter (PGT) or antagonism of EP receptors prevented the effects of PGE2 , which indicated that PGE2 activity depended on its carrier-mediated translocation from the outside to the inside of cells and that EP receptors located intracellularly (iEP) mediated the effects of PGE2 . iPGE2 acted through transactivation of epidermal growth factor-receptor (EGFR) by iEP, leading to increased expression and activity of hypoxia-inducible factor-1α (HIF-1α). Interestingly, iPGE2 also mediates the effects of PGE2 on prostate cancer PC3 cells through the axis iPGE2 -iEP receptors-EGFR-HIF-1α. Thus, this axis might be responsible for the growth-stimulating effects of PGE2 on prostate epithelial cells, thereby contributing to prostate proliferative diseases associated with chronic inflammation. Since this PGT-dependent non-canonic intracrine mechanism of PGE2 action operates in both benign and malignant prostate epithelial cells, PGT inhibitors should be tested as a novel therapeutic modality to treat prostate proliferative disease.
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Intracellular prostaglandin E2 mediates cisplatin-induced proximal tubular cell death. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:293-302. [DOI: 10.1016/j.bbamcr.2015.11.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 11/11/2015] [Accepted: 11/30/2015] [Indexed: 01/15/2023]
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Fernández-Martínez AB, Lucio-Cazaña J. Intracellular EP2 prostanoid receptor promotes cancer-related phenotypes in PC3 cells. Cell Mol Life Sci 2015; 72:3355-73. [PMID: 25828575 PMCID: PMC11113933 DOI: 10.1007/s00018-015-1891-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/10/2015] [Accepted: 03/19/2015] [Indexed: 12/23/2022]
Abstract
Prostaglandin E2 (PGE2) and hypoxia-inducible factor-1α (HIF-1α) affect many mechanisms that have been involved in the pathogenesis of prostate cancer (PC). HIF-1α, which is up-regulated by PGE2 in LNCaP cells and PC3 cells, has been shown to contribute to metastasis and chemo-resistance of castrate-resistant PC (a lethal form of PC) and to promote in PC cells migration, invasion, angiogenesis and chemoresistance. The selective blockade of PGE2-EP2 signaling pathway in PC3 cells results in inhibition of cancer cell proliferation and invasion. PGE2 affects many mechanisms that have been shown to play a role in carcinogenesis such as proliferation, apoptosis, migration, invasion and angiogenesis. Recently, we have found in PC3 cells that most of these PGE2-induced cancer-related features are due to intracellular PGE2 (iPGE2). Here, we aimed to study in PC3 cells the role of iPGE2-intracellular EP2 (iEP2)-HIF-1α signaling in several events linked to PC progression using an experimental approach involving pharmacological inhibition of the prostaglandin uptake transporter and EGFR and pharmacological and genetic modulation of EP2 receptor and HIF-1α. We found that iPGE2 increases HIF-1α expression through iEP2-dependent EGFR transactivation and that inhibition of any of the axis iEP2-EGFR-HIF-1α in cells treated with PGE2 or EP2 agonist results in prevention of the increase in PC3 cell proliferation, adhesion, migration, invasion and angiogenesis in vitro. Of note, PGE2 induced EP2 antagonist-sensitive DNA synthesis in nuclei isolated from PC3 cells, which indicates that they have functional EP2 receptors. These results suggest that PGE2-EP2 dependent intracrine mechanisms involving EGFR and HIF-1α play a role in PC.
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Affiliation(s)
- Ana Belén Fernández-Martínez
- Departamento de Biología de Sistemas, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871, Madrid, Spain,
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8
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Fernández-Martínez AB, Lucio-Cazaña FJ. Transactivation of EGFR by prostaglandin E2 receptors: a nuclear story? Cell Mol Life Sci 2015; 72:2187-98. [PMID: 25516021 PMCID: PMC11113541 DOI: 10.1007/s00018-014-1802-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 11/03/2014] [Accepted: 12/04/2014] [Indexed: 10/24/2022]
Abstract
The pharmacological modulation of hypoxia-inducible factor-1α (HIF-1α) and HIF-1α-regulated vascular endothelial growth factor-A (VEGF-A) in the kidney has therapeutic interest. Although it is assumed that prostaglandin E(2) (PGE(2)) exerts its biological effects from the extracellular medium through activation of EP receptors located at the cell membrane, we have shown in human renal proximal tubular HK-2 cells (and other cell lines) that intracellular PGE(2) regulates the expression of HIF-1α expression and the production of VEGF-A. Here, we have found--through experiments involving EP receptors agonists, EP receptor gene silencing and inhibition of the prostaglandin uptake transporter--that these biological effects of PGE(2) are mediated by intracellular EP(2) receptors. In sharp contrast with cell membrane EP(2), whose activation results in increased production of cAMP, intracellular EP(2) signaling was independent of cAMP. Instead, it involved c-src-dependent transactivation of epidermal growth factor receptor, which led to p38/ERK1/2-dependent activation of mitogen- and stress-activated kinase-1 (MSK-1) and to MSK-1-dependent-histone H3 phosphorylation and transcriptional up-regulation of retinoic acid receptor-β. Even more important, this signaling pathway was fully reproduced in nuclei isolated from HK-2 cell, which highlights the relevance of nuclear EP receptors in the up-regulation of HIF-1α. These results open the possibility that signal cascades that proceed entirely in the cell nucleus might be responsible for several PGE(2) effects that are assumed to be due to cell membrane EP receptors.
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Affiliation(s)
- Ana B Fernández-Martínez
- Departamento de Biología de Sistemas, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871, Madrid, Spain,
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9
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Madrigal-Martínez A, Cazaña FJL, Fernández-Martínez YAB. Role of intracellular prostaglandin E₂ in cancer-related phenotypes in PC3 cells. Int J Biochem Cell Biol 2014; 59:52-61. [PMID: 25462156 DOI: 10.1016/j.biocel.2014.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 10/20/2014] [Accepted: 11/03/2014] [Indexed: 11/25/2022]
Abstract
Prostaglandin E2 (PGE2) and hypoxia-inducible factor-1α (HIF-1α) affect many mechanisms that have been shown to play a role in prostate cancer. In PGE2-treated LNCaP cells, up-regulation of HIF-1α requires the internalization of PGE2, which is in sharp contrast with the generally accepted view that PGE2 acts through EP receptors located at the cell membrane. Here we aimed to study in androgen-independent PC3 cells the role of intracellular PGE2 in several events linked to prostate cancer progression. To this end, we used bromocresol green, an inhibitor of prostaglandin uptake that blocked the immediate rise in intracellular immunoreactive PGE2 following treatment with 16,16-dimethyl-PGE2. Bromocresol green prevented the stimulatory effect of 16,16-dimethyl-PGE on cell proliferation, adhesion, migration and invasion and on HIF-1α expression and activity, the latter assessed as the HIF-dependent activation of (i) a hypoxia response element-luciferase plasmid construct, (ii) production of angiogenic factor vascular endothelial growth factor-A and (iii) in vitro angiogenesis. The basal phenotype of PC3 cells was also affected by bromocresol green, that substantially lowered expression of HIF-1α, production of vascular endothelial growth factor-A and cell proliferation. These results, and the fact that we found functional intracellular EP receptors in PC3 cells, suggest that PGE2-dependent intracrine mechanisms play a role in prostate cancer Therefore, inhibition of the prostaglandin uptake transporter might be a novel therapeutic approach for the treatment of prostate cancer.
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Fernández-Martínez AB, Lucio Cazaña FJ. Prostaglandin E2 induces retinoic acid receptor-β up-regulation through MSK1. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1997-2004. [PMID: 24953041 DOI: 10.1016/j.bbamcr.2014.05.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 05/05/2014] [Accepted: 05/23/2014] [Indexed: 01/30/2023]
Abstract
The pharmacological modulation of putative renoprotective factors hypoxia-inducible factor-1α (HIF-1α) and HIF-1α-regulated vascular endothelial growth factor-A (VEGF-A) in the kidney has therapeutic interest. In human renal proximal tubular HK2 cells, prostaglandin E2 (PGE2) up-regulates HIF-1α and VEGF-A through epidermal growth factor receptor (EGFR)-dependent up-regulation of retinoic acid receptor-β (RARβ). Here we studied the role of mitogen-activated protein kinases (MAPKs) ERK1/2 and p38 and their target kinase, mitogen- and stress activated kinase-1 (MSK1), in the signaling cascade. Treatment of HK2 cells with PGE2 resulted in increased phosphorylation of EGFR, the three studied kinases and the histone H3 (Ser10) at the RARβ gene promoter (the latter has been proposed as a molecular signature of the activated RARβ gene promoter). Prevention of the phosphorylation of EGFR, ERK1/2, p38 MAPK or MSK1 is by incubating, respectively, with AG1478, PD98059, SB203580 or H89 allowed to elucidate the precise phosphorylation order in the signaling cascade triggered by PGE2: first, EGFR; then, ERK1/2 and p38 MAPK and, finally, MSK1. Phosphorylation of MSK1 led to that of Ser10 in histone H3 and to activation of RARβ gene transcription (and the consequent increase in the expression of HIF-1α and VEGF-A), which was suppressed by H89 or by transfecting cells with a vector encoding for a dominant-negative mutant of MSK1. These results highlight the relevance of MSK1 in the up-regulation of RARβ by PGE2. They also may contribute to new therapeutic approaches based upon the pharmacological control of HIF-1α/VEGF-A in the proximal tubule through the modulation of the PGE2/EGFR/MAPK/MSK1/RARβ pathway.
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Fernandez-Martínez AB, Torija AV, Carracedo J, Ramirez R, de Lucio-Cazaña FJ. Microparticles released by vascular endothelial cells increase hypoxia inducible factor expression in human proximal tubular HK-2 cells. Int J Biochem Cell Biol 2014; 53:334-42. [PMID: 24878611 DOI: 10.1016/j.biocel.2014.05.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/23/2014] [Accepted: 05/19/2014] [Indexed: 10/25/2022]
Abstract
Microparticles are produced by vesiculation of the cell plasma membrane and serve as vectors of cell-to-cell communication. Co-culture experiments have shown that hypoxia-inducible factor-α (HIF-α)-regulated-genes are up-regulated in human renal proximal tubular HK-2 cells by endothelial cell factors which might be transported inside endothelial microparticles (EMP). Here we aimed to study in HK-2 cells the effect of EMP, produced by activated endothelial cells, on HIF-α and HIF-α-regulated vascular endothelial growth factor-A (VEGF-A). EMP, at a concentration much lower than that found in plasma, increased the expression of HIF-α/VEGF-A in a COX-2/EP2 receptor dependent manner. Since the EMP/cells ratio was ∼1/1000, we hypothesized that paracrine mediators produced by HK-2 cells amplified the initial signal. This hypothesis was confirmed by two facts which also suggested that the mediators were conveyed by particles released by HK-2 cells: (i) HIF-α was up-regulated in HK-2 cells treated with the pellet obtained from the conditioned medium of the EMP-treated HK-2 cells. (ii) In transwell experiments, EMP-treated cells increased the expression of HIF-α in untreated HK-2 cells. Interestingly, we detected these cells, particles that were released by EMP-treated HK-2 cells. Depending on the pathological context, activation of HIF-α and VEGF-A signaling in renal tissue/cells may have either beneficial or harmful effects. Therefore, our results suggest that their presence in the urinary space of EMP produced by activated endothelial cells may influence the outcome of a number of renal diseases.
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Affiliation(s)
| | - Ana Valdehita Torija
- Departamento de Biología de Sistemas, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
| | - Julia Carracedo
- RETICs Red Renal (Instituto de Salud Carlos III), Avda Monforte de Lemos n° 5, 28029 Madrid, Spain; Nephrology Unit, Reina Sofía University Hospital, Avda Menéndez Pidal s/n, 14004 Córdoba, Spain; Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Avda Menéndez Pidal s/n, 14004 Córdoba, Spain
| | - Rafael Ramirez
- Departamento de Biología de Sistemas, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain; RETICs Red Renal (Instituto de Salud Carlos III), Avda Monforte de Lemos n° 5, 28029 Madrid, Spain
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12
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McCarthy TL, Yun Z, Madri JA, Centrella M. Stratified control of IGF-I expression by hypoxia and stress hormones in osteoblasts. Gene 2014; 539:141-51. [PMID: 24440782 DOI: 10.1016/j.gene.2014.01.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 01/04/2014] [Indexed: 01/11/2023]
Abstract
Bone cells respond to the integrated effects of local and systemic regulation. Here we show that hypoxia and the stress hormones PGE2 and glucocorticoid interact in complex ways in osteoblasts, converging on insulin like growth factor I (IGF-I) expression. Whereas hypoxia alone rapidly increased transcription factor HIF activity, it suppressed DNA synthesis, had no significant effects on protein synthesis or alkaline phosphatase activity, and drove discrete changes in a panel of osteoblast mRNAs. Notably, hypoxia increased expression of the acute phase response transcription factor C/EBPδ which can induce IGF-I in response to PGE2, but conversely prevented the stimulatory effect of PGE2 on IGF-I mRNA. However, unlike its effect on C/EBPδ, hypoxia suppressed expression of the obligate osteoblast transcription factor Runx2, which can activate an upstream response element in the IGF-I gene promoter. Hypoxic inhibition of IGF-I and Runx2 were enforced by glucocorticoid, and continued with prolonged exposure. Our studies thus reveal that IGF-I expression is stratified by two critical transcriptional elements in osteoblasts, which are resolved by the individual and combined effects of hypoxic stress and stress hormones. In so doing, hypoxia suppresses Runx2, limits the enhancing influence of PGE2, and interacts with glucocorticoid to reduce IGF-I expression by osteoblasts.
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Affiliation(s)
- Thomas L McCarthy
- Yale University School of Medicine, Department of Surgery, New Haven, CT 06520-8041, USA; Yale University School of Medicine, Department of Pathology, New Haven, CT 06520-8023, USA.
| | - Zhong Yun
- Yale University School of Medicine, Department of Therapeutic Radiology, New Haven, CT 06520-8040, USA
| | - Joseph A Madri
- Yale University School of Medicine, Department of Pathology, New Haven, CT 06520-8023, USA
| | - Michael Centrella
- Yale University School of Medicine, Department of Surgery, New Haven, CT 06520-8041, USA; Yale University School of Medicine, Department of Pathology, New Haven, CT 06520-8023, USA.
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Pharmacologic increase in HIF1α enhances hematopoietic stem and progenitor homing and engraftment. Blood 2013; 123:203-7. [PMID: 24167196 DOI: 10.1182/blood-2013-07-516336] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Hematopoietic stem cell (HSC) transplantation is a lifesaving therapy for a number of immunologic disorders. For effective transplant, HSCs must traffic from the peripheral blood to supportive bone marrow niches. We previously showed that HSC trafficking can be enhanced by ex vivo treatment of hematopoietic grafts with 16-16 dimethyl prostaglandin E2 (dmPGE2). While exploring regulatory molecules involved in dmPGE2 enhancement, we found that transiently increasing the transcription factor hypoxia-inducible factor 1-α (HIF1α) is required for dmPGE2-enhanced CXCR4 upregulation and enhanced migration and homing of stem and progenitor cells and that pharmacologic manipulation of HIF1α is also capable of enhancing homing and engraftment. We also now identify the specific hypoxia response element required for CXCR4 upregulation. These data define a precise mechanism through which ex vivo pulse treatment with dmPGE2 enhances the function of hematopoietic stem and progenitor cells; these data also define a role for hypoxia and HIF1α in enhancement of hematopoietic transplantation.
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Fernández-Martínez AB, Lucio Cazaña FJ. Epidermal growth factor receptor transactivation by intracellular prostaglandin E2-activated prostaglandin E2 receptors. Role in retinoic acid receptor-β up-regulation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2029-38. [PMID: 23644172 DOI: 10.1016/j.bbamcr.2013.04.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 04/22/2013] [Accepted: 04/24/2013] [Indexed: 12/21/2022]
Abstract
The pharmacological modulation of renoprotective factor vascular endothelial growth factor-A (VEGF-A) in the proximal tubule has therapeutic interest. In human proximal tubular HK-2 cells, treatment with all-trans retinoic acid or prostaglandin E2 (PGE2) triggers the production of VEGF-A. The pathway involves an initial increase in intracellular PGE2, followed by activation of EP receptors (PGE2 receptors, most likely an intracellular subset) and increase in retinoic acid receptor-β (RARβ) expression. RARβ then up-regulates transcription factor hypoxia-inducible factor-1α (HIF-1α), which increases the transcription and production of VEGF-A. Here we studied the role in this pathway of epidermal growth factor receptor (EGFR) transactivation by EP receptors. We found that EGFR inhibitor AG1478 prevented the increase in VEGF-A production induced by PGE2- and all-trans retinoic acid. This effect was due to the inhibition of the transcriptional up-regulation of RARβ, which resulted in loss of the RARβ-dependent transcriptional up-regulation of HIF-1α. PGE2 and all-trans retinoic acid also increased EGFR phosphorylation and this effect was sensitive to antagonists of EP receptors. The role of intracellular PGE2 was indicated by two facts; i) PGE2-induced EGFR phosphorylation was substantially prevented by inhibitor of prostaglandin uptake transporter bromocresol green and ii) all-trans retinoic acid treatment, which enhanced intracellular but not extracellular PGE2, had lower effect on EGFR phosphorylation upon pre-treatment with cyclooxygenase inhibitor diclofenac. Thus, EGFR transactivation by intracellular PGE2-activated EP receptors results in the sequential activation of RARβ and HIF-1α leading to increased production of VEGF-A and it may be a target for the therapeutic modulation of HIF-1α/VEGF-A.
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