1
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Tanaka H, Ozawa R, Henmi Y, Hosoda M, Karasawa T, Takahashi M, Takahashi H, Iwata H, Kuwayama T, Shirasuna K. Gasdermin D regulates soluble fms-like tyrosine kinase 1 release in macrophages. Reprod Biol 2024; 24:100857. [PMID: 38295720 DOI: 10.1016/j.repbio.2024.100857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/09/2024] [Accepted: 01/13/2024] [Indexed: 04/02/2024]
Abstract
Preeclampsia (PE) is a serious complication, and soluble fms-like tyrosine kinase (sFLT1) released from the placenta is one of the causes of PE pathology. Trophoblasts are the primary source of sFLT1; however, monocytes/macrophages exist enough in the placenta can also secrete sFLT1. Sterile inflammatory responses, especially NLRP3 inflammasome and its downstream gasdermin D (GSDMD)-regulated pyroptosis, may be involved in the development of PE pathology. In this study, we investigated whether human monocyte/macrophage cell line THP-1 cells secrete sFLT1 depending on the NLRP3 inflammasome and GSDMD. To differentiate THP-1 monocytes into macrophages, treatment with phorbol 12-myristate 13-acetate (PMA) induced sFLT1 with interleukin (IL)- 1β, but did not induce cell lytic death. IL-1β secretion induced by PMA inhibited by deletion of NLRP3 and inhibitors of NLRP3 and caspase-1, but deletion of NLRP3 and these inhibitors did not affect sFLT1 secretion in THP-1 cells. Both gene deletion and inhibition of GSDMD dramatically decreased IL-1β and sFLT1 secretion from THP-1 cells. Treatment with CA074-ME (a cathepsin B inhibitor) also reduced the secretion of both sFLT1 and IL-1β in THP-1 cells. In conclusion, THP-1 macrophages release sFLT1 in a GSDMD-dependent manner, but not in the NLRP3 inflammasome-dependent manner, and this sFLT1 release may be associated with the non-lytic role of GSDMD. In addition, sFLT1 levels induced by PMA are associated with lysosomal cathepsin B in THP-1 macrophages. We suggest that sFLT1 synthesis regulated by GSDMD are involved in the pathology of PE.
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Affiliation(s)
- Hazuki Tanaka
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan
| | - Ren Ozawa
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan
| | - Yuka Henmi
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan
| | - Manabu Hosoda
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan
| | - Tadayoshi Karasawa
- Division of Inflammation Research, Center for Molecular Medicine, Jichi Medical University, Japan
| | - Masafumi Takahashi
- Division of Inflammation Research, Center for Molecular Medicine, Jichi Medical University, Japan
| | - Hironori Takahashi
- Department of Obstetrics and Gynecology, Jichi Medical University, Japan
| | - Hisataka Iwata
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan
| | - Takehito Kuwayama
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan
| | - Koumei Shirasuna
- Laboratory of Animal Reproduction, Department of Animal Science, Tokyo University of Agriculture, Japan.
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2
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Horan DE, Kielsen K, Weischendorff SW, Sørum ME, Kammersgaard MB, Ifversen M, Nielsen C, Ryder LP, Johansson PI, Müller K. sVEGF-R1 in acute non-infectious toxicity syndromes after pediatric allogeneic hematopoietic stem cell transplantation. Transpl Immunol 2024; 82:101975. [PMID: 38122992 DOI: 10.1016/j.trim.2023.101975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/11/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND Allogeneic hematopoietic stem cell transplantation (HSCT) is challenged by acute non-infectious toxicities, including sinusoidal obstruction syndrome (SOS), engraftment syndrome (ES) and capillary leak syndrome (CLS) among others. These complications are thought to be driven by a dysfunctional vascular endothelium, but the pathophysiological mechanisms remain incompletely understood, and the diagnoses are challenged by purely clinical diagnostic criteria that are partly overlapping, limiting the possibilities for progress in this field. There is, however, increasing evidence suggesting that these challenges may be met through the development of diagnostic biomarkers to improve diagnostic accuracy of pathogenetically homogenous entities, improved pre-transplant risk assessment and the early identification of patients with increased need for specific treatment. Soluble vascular endothelial growth factor receptor-1 (sVEGF-R1) is emerging as an important biomarker of endothelial damage in patients with trauma and sepsis but has not been studied in HSCT. OBJECTIVES To investigate sVEGF-R1 as a marker of endothelial damage in pediatric HSCT patients by exploring associations with SOS, CLS, ES, and acute graft-versus-host disease (aGvHD). METHODS We prospectively included 113 children undergoing myeloablative HSCT and measured sVEGF-R1 in plasma samples obtained weekly during the early period of transplantation and 3 months post-transplant. RESULTS All over, sVEGF-R1 levels were significantly increased from day +7 after graft infusion, peaking at day +30, most pronounced in patients receiving busulfan. Patients considered to be at increased risk of SOS and therefore commenced on prophylactic defibrotide had significantly elevated levels of sVEGF-R1 before start of conditioning (446 pg/mL vs. 281 pg/mL, p = 0.0035), and this treatment appeared to stabilize sVEGF-R1 levels compared to patients not treated with defibrotide. Thirteen (11.5%) children meeting the modified Seattle criteria for SOS at median day +8 (1-18), had significantly elevated sVEGF-R1 levels on day +14 (489 pg/mL vs. 327 pg/mL, p = 0.007). In contrast. sVEGF-R1 levels in the much broader group of patients (45.1%) meeting EBMT-SOS criteria, including patients with very mild disease, did not overall differ in sVEGF-R1 levels, but higher sVEGF-R1 levels were seen in EBMT-SOS patients with an increased need for diuretic treatment. Importantly, sVEGF-R1 levels were not associated with ES and CLS but were significantly increased on day +30 in patients with grade III-IV aGvHD (OR = 4.2 pr. quartile, p = 0.023). CONCLUSION VEGF-R1 levels are found to be increased in pediatric patients developing SOS, reflecting the severity of morbidity. sVEGF-R1 were unassociated with both CLS and ES. The potential of sVEGF-R1 as a clinically useful biomarker for SOS should be further explored to improve pre-transplant SOS-risk assessment, SOS-severity grading, and to guide treatment.
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Affiliation(s)
- Denise Elbæk Horan
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Institute for Inflammation Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Katrine Kielsen
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Department of Clinical Immunology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Sarah Wegener Weischendorff
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Institute for Inflammation Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Maria Ebbesen Sørum
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Institute for Inflammation Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Marte B Kammersgaard
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Institute for Inflammation Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Marianne Ifversen
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Claus Nielsen
- Institute for Inflammation Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
| | - Lars P Ryder
- Department of Clinical Immunology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Pär I Johansson
- Section for Transfusion Medicine, Capital Region Blood Bank, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
| | - Klaus Müller
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Institute for Inflammation Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Institute of Clinical Medicine, University of Copenhagen, Denmark.
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3
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Payne LB, Abdelazim H, Hoque M, Barnes A, Mironovova Z, Willi CE, Darden J, Houk C, Sedovy MW, Johnstone SR, Chappell JC. A Soluble Platelet-Derived Growth Factor Receptor-β Originates via Pre-mRNA Splicing in the Healthy Brain and Is Upregulated during Hypoxia and Aging. Biomolecules 2023; 13:711. [PMID: 37189457 PMCID: PMC10136073 DOI: 10.3390/biom13040711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 05/17/2023] Open
Abstract
The platelet-derived growth factor-BB (PDGF-BB) pathway provides critical regulation of cerebrovascular pericytes, orchestrating their investment and retention within the brain microcirculation. Dysregulated PDGF Receptor-beta (PDGFRβ) signaling can lead to pericyte defects that compromise blood-brain barrier (BBB) integrity and cerebral perfusion, impairing neuronal activity and viability, which fuels cognitive and memory deficits. Receptor tyrosine kinases such as PDGF-BB and vascular endothelial growth factor-A (VEGF-A) are often modulated by soluble isoforms of cognate receptors that establish signaling activity within a physiological range. Soluble PDGFRβ (sPDGFRβ) isoforms have been reported to form by enzymatic cleavage from cerebrovascular mural cells, and pericytes in particular, largely under pathological conditions. However, pre-mRNA alternative splicing has not been widely explored as a possible mechanism for generating sPDGFRβ variants, and specifically during tissue homeostasis. Here, we found sPDGFRβ protein in the murine brain and other tissues under normal, physiological conditions. Utilizing brain samples for follow-on analysis, we identified mRNA sequences corresponding to sPDGFRβ isoforms, which facilitated construction of predicted protein structures and related amino acid sequences. Human cell lines yielded comparable sequences and protein model predictions. Retention of ligand binding capacity was confirmed for sPDGFRβ by co-immunoprecipitation. Visualizing fluorescently labeled sPDGFRβ transcripts revealed a spatial distribution corresponding to murine brain pericytes alongside cerebrovascular endothelium. Soluble PDGFRβ protein was detected throughout the brain parenchyma in distinct regions, such as along the lateral ventricles, with signals also found more broadly adjacent to cerebral microvessels consistent with pericyte labeling. To better understand how sPDGFRβ variants might be regulated, we found elevated transcript and protein levels in the murine brain with age, and acute hypoxia increased sPDGFRβ variant transcripts in a cell-based model of intact vessels. Our findings indicate that soluble isoforms of PDGFRβ likely arise from pre-mRNA alternative splicing, in addition to enzymatic cleavage mechanisms, and these variants exist under normal physiological conditions. Follow-on studies will be needed to establish potential roles for sPDGFRβ in regulating PDGF-BB signaling to maintain pericyte quiescence, BBB integrity, and cerebral perfusion-critical processes underlying neuronal health and function, and in turn, memory and cognition.
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Affiliation(s)
- Laura Beth Payne
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Hanaa Abdelazim
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Maruf Hoque
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Audra Barnes
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
- Department of Biomedical Engineering and Mechanics, School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Zuzana Mironovova
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Caroline E. Willi
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Jordan Darden
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Clifton Houk
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
| | - Meghan W. Sedovy
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
| | - Scott R. Johnstone
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - John C. Chappell
- Fralin Biomedical Research Institute (FBRI) at Virginia Tech-Carilion (VTC), Roanoke, VA 24016, USA
- FBRI Center for Vascular and Heart Research, Roanoke, VA 24016, USA
- Department of Biomedical Engineering and Mechanics, School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA 24061, USA
- Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
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4
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Payne LB, Abdelazim H, Hoque M, Barnes A, Mironovova Z, Willi CE, Darden J, Jenkins-Houk C, Sedovy MW, Johnstone SR, Chappell JC. A Soluble Platelet-Derived Growth Factor Receptor-β Originates via Pre-mRNA Splicing in the Healthy Brain and is Differentially Regulated during Hypoxia and Aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.03.527005. [PMID: 36778261 PMCID: PMC9915746 DOI: 10.1101/2023.02.03.527005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The platelet-derived growth factor-BB (PDGF-BB) pathway provides critical regulation of cerebrovascular pericytes, orchestrating their investment and retention within the brain microcirculation. Dysregulated PDGF Receptor-beta (PDGFRβ) signaling can lead to pericyte defects that compromise blood-brain barrier (BBB) integrity and cerebral perfusion, impairing neuronal activity and viability, which fuels cognitive and memory deficits. Receptor tyrosine kinases (RTKs) like PDGF-BB and vascular endothelial growth factor-A (VEGF-A) are often modulated by soluble isoforms of cognate receptors that establish signaling activity within a physiological range. Soluble PDGFRβ (sPDGFRβ) isoforms have been reported to form by enzymatic cleavage from cerebrovascular mural cells, and pericytes in particular, largely under pathological conditions. However, pre-mRNA alternative splicing has not been widely explored as a possible mechanism for generating sPDGFRβ variants, and specifically during tissue homeostasis. Here, we found sPDGFRβ protein in the murine brain and other tissues under normal, physiological conditions. Utilizing brain samples for follow-on analysis, we identified mRNA sequences corresponding to sPDGFRβ isoforms, which facilitated construction of predicted protein structures and related amino acid sequences. Human cell lines yielded comparable sequences and protein model predictions. Retention of ligand binding capacity was confirmed for sPDGFRβ by co-immunoprecipitation. Visualizing fluorescently labeled sPDGFRβ transcripts revealed a spatial distribution corresponding to murine brain pericytes alongside cerebrovascular endothelium. Soluble PDGFRβ protein was detected throughout the brain parenchyma in distinct regions such as along the lateral ventricles, with signals also found more broadly adjacent to cerebral microvessels consistent with pericyte labeling. To better understand how sPDGFRβ variants might be regulated, we found elevated transcript and protein levels in the murine brain with age, and acute hypoxia increased sPDGFRβ variant transcripts in a cell-based model of intact vessels. Our findings indicate that soluble isoforms of PDGFRβ likely arise from pre-mRNA alternative splicing, in addition to enzymatic cleavage mechanisms, and these variants exist under normal physiological conditions. Follow-on studies will be needed to establish potential roles for sPDGFRβ in regulating PDGF-BB signaling to maintain pericyte quiescence, BBB integrity, and cerebral perfusion - critical processes underlying neuronal health and function, and in turn memory and cognition.
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5
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Loyer C, Lapostolle A, Urbina T, Elabbadi A, Lavillegrand JR, Chaigneau T, Simoes C, Dessajan J, Desnos C, Morin-Brureau M, Chantran Y, Aucouturier P, Guidet B, Voiriot G, Ait-Oufella H, Elbim C. Impairment of neutrophil functions and homeostasis in COVID-19 patients: association with disease severity. Crit Care 2022; 26:155. [PMID: 35637483 PMCID: PMC9149678 DOI: 10.1186/s13054-022-04002-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 04/27/2022] [Indexed: 01/08/2023] Open
Abstract
Background A dysregulated immune response is emerging as a key feature of critical illness in COVID-19. Neutrophils are key components of early innate immunity that, if not tightly regulated, contribute to uncontrolled systemic inflammation. We sought to decipher the role of neutrophil phenotypes, functions, and homeostasis in COVID-19 disease severity and outcome. Methods By using flow cytometry, this longitudinal study compares peripheral whole-blood neutrophils from 90 COVID-19 ICU patients with those of 22 SARS-CoV-2-negative patients hospitalized for severe community-acquired pneumonia (CAP) and 38 healthy controls. We also assessed correlations between these phenotypic and functional indicators and markers of endothelial damage as well as disease severity. Results At ICU admission, the circulating neutrophils of the COVID-19 patients showed continuous basal hyperactivation not seen in CAP patients, associated with higher circulating levels of soluble E- and P-selectin, which reflect platelet and endothelial activation. Furthermore, COVID-19 patients had expanded aged-angiogenic and reverse transmigrated neutrophil subsets—both involved in endothelial dysfunction and vascular inflammation. Simultaneously, COVID-19 patients had significantly lower levels of neutrophil oxidative burst in response to bacterial formyl peptide. Moreover patients dying of COVID-19 had significantly higher expansion of aged-angiogenic neutrophil subset and greater impairment of oxidative burst response than survivors. Conclusions These data suggest that neutrophil exhaustion may be involved in the pathogenesis of severe COVID-19 and identify angiogenic neutrophils as a potentially harmful subset involved in fatal outcome. Graphic Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13054-022-04002-3.
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Affiliation(s)
- Chloé Loyer
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France
| | - Arnaud Lapostolle
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France
| | - Tomas Urbina
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Alexandre Elabbadi
- Service de Médecine Intensive-Réanimation, Hôpital Tenon, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Jean-Rémi Lavillegrand
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France.,INSERM U970, Cardiovascular Research Center, Université de Paris, Paris, France
| | - Thomas Chaigneau
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France
| | - Coraly Simoes
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France
| | - Julien Dessajan
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Tenon, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Cyrielle Desnos
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Tenon, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Mélanie Morin-Brureau
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France
| | - Yannick Chantran
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France.,Département d'Immunologie Biologique, Hôpital Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Pierre Aucouturier
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France.,Sorbonne Université, Paris, France.,Département d'Immunologie Biologique, Hôpital Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Bertrand Guidet
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Guillaume Voiriot
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Tenon, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Hafid Ait-Oufella
- Sorbonne Université, Paris, France.,Service de Médecine Intensive-Réanimation, Hôpital Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France.,INSERM U970, Cardiovascular Research Center, Université de Paris, Paris, France
| | - Carole Elbim
- INSERM, UMRS 938, Hôpital St-Antoine, Centre de Recherche Saint-Antoine, Sorbonne Université, 75012, Paris, France. .,Sorbonne Université, Paris, France.
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6
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De Vita A, Vanni S, Miserocchi G, Fausti V, Pieri F, Spadazzi C, Cocchi C, Liverani C, Calabrese C, Casadei R, Recine F, Gurrieri L, Bongiovanni A, Ibrahim T, Mercatali L. A Rationale for the Activity of Bone Target Therapy and Tyrosine Kinase Inhibitor Combination in Giant Cell Tumor of Bone and Desmoplastic Fibroma: Translational Evidences. Biomedicines 2022; 10:biomedicines10020372. [PMID: 35203581 PMCID: PMC8962296 DOI: 10.3390/biomedicines10020372] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/24/2022] [Accepted: 02/01/2022] [Indexed: 12/10/2022] Open
Abstract
Giant cell tumor of bone (GCTB) and desmoplastic fibroma (DF) are bone sarcomas with intermediate malignant behavior and unpredictable prognosis. These locally aggressive neoplasms exhibit a predilection for the long bone or mandible of young adults, causing a severe bone resorption. In particular, the tumor stromal cells of these lesions are responsible for the recruiting of multinucleated giant cells which ultimately lead to bone disruption. In this regard, the underlying pathological mechanism of osteoclastogenesis processes in GCTB and DF is still poorly understood. Although current therapeutic strategy involves surgery, radiotherapy and chemotherapy, the benefit of the latter is still debated. Thus, in order to shed light on these poorly investigated diseases, we focused on the molecular biology of GCTB and DF. The expression of bone-vicious-cycle- and neoangiogenesis-related genes was investigated. Moreover, combining patient-derived primary cultures with 2D and 3D culture platforms, we investigated the role of denosumab and levantinib in these diseases. The results showed the upregulation of RANK-L, RANK, OPN, CXCR4, RUNX2 and FLT1 and the downregulation of OPG and CXCL12 genes, underlining their involvement and promising role in these neoplasms. Furthermore, in vitro analyses provided evidence for suggesting the combination of denosumab and lenvatinib as a promising therapeutic strategy in GCTB and DF compared to monoregimen chemotherapy. Furthermore, in vivo zebrafish analyses corroborated the obtained data. Finally, the clinical observation of retrospectively enrolled patients confirmed the usefulness of the reported results. In conclusion, here we report for the first time a molecular and pharmacological investigation of GCTB and DF combining the use of translational and clinical data. Taken together, these results represent a starting point for further analyses aimed at improving GCTB and DF management.
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Affiliation(s)
- Alessandro De Vita
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Silvia Vanni
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
- Correspondence:
| | - Giacomo Miserocchi
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Valentina Fausti
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Federica Pieri
- Pathology Unit, Morgagni-Pierantoni Hospital, 47121 Forli, Italy;
| | - Chiara Spadazzi
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Claudia Cocchi
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Chiara Liverani
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Chiara Calabrese
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Roberto Casadei
- Orthopedic Unit, Morgagni-Pierantoni Hospital, 47121 Forli, Italy;
| | - Federica Recine
- Medical Oncology Unit, Azienda Ospedaliera San Giovanni Addolorata, 00184 Roma, Italy;
| | - Lorena Gurrieri
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Alberto Bongiovanni
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
| | - Toni Ibrahim
- Osteoncology, Bone and Soft Tissue Sarcomas and Innovative Therapies Unit, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy;
| | - Laura Mercatali
- Osteoncology and Rare Tumors Center, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) “Dino Amadori”, 47014 Meldola, Italy; (A.D.V.); (G.M.); (V.F.); (C.S.); (C.C.); (C.L.); (C.C.); (L.G.); (A.B.); (L.M.)
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Valanti EK, Dalakoura-Karagkouni K, Fotakis P, Vafiadaki E, Mantzoros CS, Chroni A, Zannis V, Kardassis D, Sanoudou D. Reconstituted HDL-apoE3 promotes endothelial cell migration through ID1 and its downstream kinases ERK1/2, AKT and p38 MAPK. Metabolism 2022; 127:154954. [PMID: 34875308 DOI: 10.1016/j.metabol.2021.154954] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/15/2021] [Accepted: 11/30/2021] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Atherosclerotic Coronary Artery Disease (ASCAD) is the leading cause of mortality worldwide. Novel therapeutic approaches aiming to improve the atheroprotective functions of High Density Lipoprotein (HDL) include the use of reconstituted HDL forms containing human apolipoprotein A-I (rHDL-apoA-I). Given the strong atheroprotective properties of apolipoprotein E3 (apoE3), rHDL-apoE3 may represent an attractive yet largely unexplored therapeutic agent. OBJECTIVE To evaluate the atheroprotective potential of rHDL-apoE3 starting with the unbiased assessment of global transcriptome effects and focusing on endothelial cell (EC) migration as a critical process in re-endothelialization and atherosclerosis prevention. The cellular, molecular and functional effects of rHDL-apoE3 on EC migration-associated pathways were assessed, as well as the potential translatability of these findings in vivo. METHODS Human Aortic ECs (HAEC) were treated with rHDL-apoE3 and total RNA was analyzed by whole genome microarrays. Expression and phosphorylation changes of key EC migration-associated molecules were validated by qRT-PCR and Western blot analysis in primary HAEC, Human Coronary Artery ECs (HCAEC) and the human EA.hy926 EC line. The capacity of rHDL-apoE3 to stimulate EC migration was assessed by wound healing and transwell migration assays. The contribution of MEK1/2, PI3K and the transcription factor ID1 in rHDL-apoE3-induced EC migration and activation of EC migration-related effectors was assessed using specific inhibitors (PD98059: MEK1/2, LY294002: PI3K) and siRNA-mediated gene silencing, respectively. The capacity of rHDL-apoE3 to improve vascular permeability and hypercholesterolemia in vivo was tested in a mouse model of hypercholesterolemia (apoE KO mice) using Evans Blue assays and lipid/lipoprotein analysis in the serum, respectively. RESULTS rHDL-apoE3 induced significant expression changes in 198 genes of HAEC mainly involved in re-endothelialization and atherosclerosis-associated functions. The most pronounced effect was observed for EC migration, with 42/198 genes being involved in the following EC migration-related pathways: 1) MEK/ERK, 2) PI3K/AKT/eNOS-MMP2/9, 3) RHO-GTPases, 4) integrin. rHDL-apoE3 induced changes in 24 representative transcripts of these pathways in HAEC, increasing the expression of their key proteins PIK3CG, EFNB2, ID1 and FLT1 in HCAEC and EA.hy926 cells. In addition, rHDL-apoE3 stimulated migration of HCAEC and EA.hy926 cells, and the migration was markedly attenuated in the presence of PD98059 or LY294002. rHDL-apoE3 also increased the phosphorylation of ERK1/2, AKT, eNOS and p38 MAPK in these cells, while PD98059 and LY294002 inhibited rHDL-apoE3-induced phosphorylation of ERK1/2, AKT and p38 MAPK, respectively. LY had no effect on rHDL-apoE3-mediated eNOS phosphorylation. ID1 siRNA markedly decreased EA.hy926 cell migration by inhibiting rHDL-apoE3-triggered ERK1/2 and AKT phosphorylation. Finally, administration of a single dose of rHDL-apoE3 in apoE KO mice markedly improved vascular permeability as demonstrated by the reduced concentration of Evans Blue dye in tissues such as the stomach, the tongue and the urinary bladder and ameliorated hypercholesterolemia. CONCLUSIONS rHDL-apoE3 significantly enhanced EC migration in vitro, predominantly via overexpression of ID1 and subsequent activation of MEK1/2 and PI3K, and their downstream targets ERK1/2, AKT and p38 MAPK, respectively, and improved vascular permeability in vivo. These novel insights into the rHDL-apoE3 functions suggest a potential clinical use to promote re-endothelialization and retard development of atherosclerosis.
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Affiliation(s)
- Eftaxia-Konstantina Valanti
- 4th Department of Internal Medicine, Clinical Genomics and Pharmacogenomics Unit, 'Attikon' Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece; Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Katerina Dalakoura-Karagkouni
- Laboratory of Biochemistry, University of Crete Medical School, Heraklion, Greece; Division of Gene Regulation and Genomics, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology of Hellas, Heraklion, Greece
| | | | - Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | | | - Angeliki Chroni
- Institute of Biosciences and Applications, National Center for Scientific Research "Demokritos", Athens, Greece
| | - Vassilis Zannis
- Molecular Genetics, Boston University Medical School, Boston, USA
| | - Dimitris Kardassis
- Laboratory of Biochemistry, University of Crete Medical School, Heraklion, Greece; Division of Gene Regulation and Genomics, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology of Hellas, Heraklion, Greece
| | - Despina Sanoudou
- 4th Department of Internal Medicine, Clinical Genomics and Pharmacogenomics Unit, 'Attikon' Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece; Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, Athens, Greece; Center for New Biotechnologies and Precision Medicine, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
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Uemura A, Fruttiger M, D'Amore PA, De Falco S, Joussen AM, Sennlaub F, Brunck LR, Johnson KT, Lambrou GN, Rittenhouse KD, Langmann T. VEGFR1 signaling in retinal angiogenesis and microinflammation. Prog Retin Eye Res 2021; 84:100954. [PMID: 33640465 PMCID: PMC8385046 DOI: 10.1016/j.preteyeres.2021.100954] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 02/12/2021] [Accepted: 02/19/2021] [Indexed: 12/13/2022]
Abstract
Five vascular endothelial growth factor receptor (VEGFR) ligands (VEGF-A, -B, -C, -D, and placental growth factor [PlGF]) constitute the VEGF family. VEGF-A binds VEGF receptors 1 and 2 (VEGFR1/2), whereas VEGF-B and PlGF only bind VEGFR1. Although much research has been conducted on VEGFR2 to elucidate its key role in retinal diseases, recent efforts have shown the importance and involvement of VEGFR1 and its family of ligands in angiogenesis, vascular permeability, and microinflammatory cascades within the retina. Expression of VEGFR1 depends on the microenvironment, is differentially regulated under hypoxic and inflammatory conditions, and it has been detected in retinal and choroidal endothelial cells, pericytes, retinal and choroidal mononuclear phagocytes (including microglia), Müller cells, photoreceptor cells, and the retinal pigment epithelium. Whilst the VEGF-A decoy function of VEGFR1 is well established, consequences of its direct signaling are less clear. VEGFR1 activation can affect vascular permeability and induce macrophage and microglia production of proinflammatory and proangiogenic mediators. However the ability of the VEGFR1 ligands (VEGF-A, PlGF, and VEGF-B) to compete against each other for receptor binding and to heterodimerize complicates our understanding of the relative contribution of VEGFR1 signaling alone toward the pathologic processes seen in diabetic retinopathy, retinal vascular occlusions, retinopathy of prematurity, and age-related macular degeneration. Clinically, anti-VEGF drugs have proven transformational in these pathologies and their impact on modulation of VEGFR1 signaling is still an opportunity-rich field for further research.
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Affiliation(s)
- Akiyoshi Uemura
- Department of Retinal Vascular Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.
| | - Marcus Fruttiger
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, UK.
| | - Patricia A D'Amore
- Schepens Eye Research Institute of Massachusetts Eye and Ear, 20 Staniford Street, Boston, MA, 02114, USA.
| | - Sandro De Falco
- Angiogenesis Laboratory, Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", Via Pietro Castellino 111, 80131 Naples, Italy; ANBITION S.r.l., Via Manzoni 1, 80123, Naples, Italy.
| | - Antonia M Joussen
- Department of Ophthalmology, Charité-Universitätsmedizin Berlin, Hindenburgdamm 30, 12200 Berlin, and Augustenburger Platz 1, 13353, Berlin, Germany.
| | - Florian Sennlaub
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, F-75012, Paris, France.
| | - Lynne R Brunck
- Bayer Consumer Care AG, Pharmaceuticals, Peter-Merian-Strasse 84, CH-4052 Basel, Switzerland.
| | - Kristian T Johnson
- Bayer Consumer Care AG, Pharmaceuticals, Peter-Merian-Strasse 84, CH-4052 Basel, Switzerland.
| | - George N Lambrou
- Bayer Consumer Care AG, Pharmaceuticals, Peter-Merian-Strasse 84, CH-4052 Basel, Switzerland.
| | - Kay D Rittenhouse
- Bayer Consumer Care AG, Pharmaceuticals, Peter-Merian-Strasse 84, CH-4052 Basel, Switzerland.
| | - Thomas Langmann
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Joseph-Stelzmann-Str. 9, 50931, Cologne, Germany.
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Guo X, Wang Y, Yang L, Wang P, Chen K, Zhou L, Wu Y. Comparison of conbercept and ranibizumab combined mitomycin C-augmented trabeculectomy for neovascular glaucoma. Int Ophthalmol 2021; 41:2869-2877. [PMID: 33895882 DOI: 10.1007/s10792-021-01846-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 04/08/2021] [Indexed: 12/18/2022]
Abstract
PURPOSE To compare the efficacy and security of conbercept and ranibizumab combined with trabeculectomy and panretinal photocoagulation for neovascular glaucoma (NVG). METHODS One hundred and sixty patients with NVG were randomly divided into a conbercept group comprised of 80 patients and a ranibizumab group comprised of 80 patients. The postoperative and preoperative visual acuities, intraocular pressures frequency of anti-glaucoma medications, and surgical complications were recorded. The expressions of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor (FLT-1), and placenta-like growth factor (PLGF) in the aqueous humor were determined using an enzyme-linked immunosorbent assay. Examining the fundus and obtaining photographs used indirect ophthalmoscopy. Kaplan-Meier and log-rank analyses estimated the success rates. RESULTS All patient follow-up periods were at 1 year. The differences observed in IOP and the frequencies of anti-glaucoma medications at various follow-up time points were not statistically significant (all P > 0.05). The differences observed in both the group visual acuities at various follow-up time points were not statistically significant (P > 0.05). Rates of surgery complications were 18.75% and 25.00% in the conbercept group and ranibizumab group, respectively. The expressions of VEGF, FLT-1, and PLGF significantly decreased (all P < 0.05). The recurrence percentages were 30.00% and 36.25% after conbercept and ranibizumab treatment, respectively. CONCLUSION The conbercept effects were similar with that of ranibizumab. Intravitreal injection of conbercept was effective for NVG treatment, which provides a new therapeutic drug for NVG treatment.
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Affiliation(s)
- Xiaohong Guo
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China
| | - Yuwen Wang
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China
| | - Liangyan Yang
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China
| | - Pengyun Wang
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China
| | - Kan Chen
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China
| | - Lei Zhou
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China
| | - Yue Wu
- Department of Ophthalmology, Ningbo Eye Hospital, No. 599 Beimingcheng Road, Yinzhou District, Ningbo, 315000, Zhejiang Province, China.
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Lv Y, Lu X, Li C, Fan Y, Ji X, Long W, Meng L, Wu L, Wang L, Lv M, Ding H. miR-145–5p promotes trophoblast cell growth and invasion by targeting FLT1. Life Sci 2019; 239:117008. [DOI: 10.1016/j.lfs.2019.117008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/09/2019] [Accepted: 10/20/2019] [Indexed: 11/25/2022]
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11
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Modulation of Receptor Tyrosine Kinase Activity through Alternative Splicing of Ligands and Receptors in the VEGF-A/VEGFR Axis. Cells 2019; 8:cells8040288. [PMID: 30925751 PMCID: PMC6523102 DOI: 10.3390/cells8040288] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 03/19/2019] [Accepted: 03/22/2019] [Indexed: 12/14/2022] Open
Abstract
Vascular endothelial growth factor A (VEGF-A) signaling is essential for physiological and pathological angiogenesis. Alternative splicing of the VEGF-A pre-mRNA gives rise to a pro-angiogenic family of isoforms with a differing number of amino acids (VEGF-Axxxa), as well as a family of isoforms with anti-angiogenic properties (VEGF-Axxxb). The biological functions of VEGF-A proteins are mediated by a family of cognate protein tyrosine kinase receptors, known as the VEGF receptors (VEGFRs). VEGF-A binds to both VEGFR-1, largely suggested to function as a decoy receptor, and VEGFR-2, the predominant signaling receptor. Both VEGFR-1 and VEGFR-2 can also be alternatively spliced to generate soluble isoforms (sVEGFR-1/sVEGFR-2). The disruption of the splicing of just one of these genes can result in changes to the entire VEGF-A/VEGFR signaling axis, such as the increase in VEGF-A165a relative to VEGF-A165b resulting in increased VEGFR-2 signaling and aberrant angiogenesis in cancer. Research into this signaling axis has recently focused on manipulating the splicing of these genes as a potential therapeutic avenue in disease. Therefore, further research into understanding the mechanisms by which the splicing of VEGF-A/VEGFR-1/VEGFR-2 is regulated will help in the development of drugs aimed at manipulating splicing or inhibiting specific splice isoforms in a therapeutic manner.
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Raikwar NS, Shibuya M, Thomas CP. VEGF-A selectively inhibits FLT1 ectodomain shedding independent of receptor activation and receptor endocytosis. Am J Physiol Cell Physiol 2018; 315:C214-C224. [PMID: 29719170 PMCID: PMC6139503 DOI: 10.1152/ajpcell.00247.2017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 03/28/2018] [Accepted: 04/11/2018] [Indexed: 11/22/2022]
Abstract
Ectodomain shedding and regulated intracellular proteolysis can determine the fate or function of cell surface proteins. Fms-related tyrosine kinase (FLT) or VEGF receptor 1 is a high-affinity cell surface VEGF-A receptor tyrosine kinase that is constitutively cleaved to release an NH2-terminal VEGF-A binding ectodomain that, once shed, can antagonize the effects of VEGF-A in the extracellular milieu. We evaluated the effect of VEGF-A on FLT1 cleavage in native cells and in transient and stable expression systems. We demonstrate that VEGF-A inhibits FLT1 ectodomain cleavage in a time- and dose-dependent manner, whereas VEGF-A knockdown in HEK293 cells increases ectodomain shedding. Although kinase insert domain receptor (KDR) or VEGF receptor 2, analogous to FLT1, is also subject to extracellular and intracellular cleavage, VEGF-A does not inhibit KDR cleavage. VEGF-A inhibition of FLT1 cleavage is not dependent on FLT1 tyrosine kinase activity or the intracellular FLT1 residues. N-acetylleucylleucylnorleucinal (ALLN), a proteasomal inhibitor; bafilomycin A, an inhibitor of endosomal acidification; and dynasore, a dynamin inhibitor, all increase the abundance of FLT1 and the shed ectodomain, indicating that FLT1 is subject to dynamin-mediated endocytosis and susceptible to proteasomal and lysosomal degradation. VEGF-A inhibition of cleavage is not reversed by ALLN, bafilomycin A, or dynasore. However, a 30 AA deletion in the extracellular immunoglobulin 7 domain leads to enhanced cleavage of Flt1 with a significant reduction of the VEGF inhibitory effect. Our results indicate that the inhibition of FLT1 ectodomain cleavage by VEGF-A is dependent neither on receptor activation nor on internalization nor a consequence of receptor degradation and likely represents a direct inhibitory effect on receptor cleavage.
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Affiliation(s)
- Nandita S Raikwar
- Department of Internal Medicine, University of Iowa Carver College of Medicine , Iowa City, Iowa
| | - Masabumi Shibuya
- Institute of Physiology and Medicine, Jobu University, Takasaki, Gunma, Japan
| | - Christie P Thomas
- Department of Internal Medicine, University of Iowa Carver College of Medicine , Iowa City, Iowa
- Department of Pediatrics, University of Iowa Carver College of Medicine , Iowa City, Iowa
- Department of Obstetrics, University of Iowa Carver College of Medicine , Iowa City, Iowa
- Graduate Program in Molecular Medicine, University of Iowa Carver College of Medicine , Iowa City, Iowa
- Veterans Affairs Medical Center , Iowa City, Iowa
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Kreitman M, Noronha A, Yarden Y. Irreversible modifications of receptor tyrosine kinases. FEBS Lett 2018; 592:2199-2212. [PMID: 29790151 DOI: 10.1002/1873-3468.13095] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/12/2018] [Accepted: 05/08/2018] [Indexed: 01/18/2023]
Abstract
Each group of the 56 receptor tyrosine kinases (RTK) binds with one or more soluble growth factors and coordinates a vast array of cellular functions. These outcomes are tightly regulated by inducible post-translational events, such as tyrosine phosphorylation, ubiquitination, ectodomain shedding, and regulated intramembrane proteolysis. Because of the delicate balance required for appropriate RTK function, cells may become pathogenic upon dysregulation of RTKs themselves or their post-translational covalent modifications. For example, reduced ectodomain shedding and decreased ubiquitination of the cytoplasmic region, both of which enhance growth factor signals, characterize malignant cells. Whereas receptor phosphorylation and ubiquitination are reversible, proteolytic cleavage events are irreversible, and either modification might alter the subcellular localization of RTKs. Herein, we focus on ectodomain shedding by metalloproteinases (including ADAM family proteases), cleavage within the membrane or cytoplasmic regions of RTKs (by gamma-secretases and caspases, respectively), and complete receptor proteolysis in lysosomes and proteasomes. Roles of irreversible modifications in RTK signaling, pathogenesis, and pharmacology are highlighted.
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Affiliation(s)
- Matthew Kreitman
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Ashish Noronha
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Yosef Yarden
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
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Failla CM, Carbo M, Morea V. Positive and Negative Regulation of Angiogenesis by Soluble Vascular Endothelial Growth Factor Receptor-1. Int J Mol Sci 2018; 19:ijms19051306. [PMID: 29702562 PMCID: PMC5983705 DOI: 10.3390/ijms19051306] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 04/23/2018] [Accepted: 04/24/2018] [Indexed: 12/20/2022] Open
Abstract
Vascular endothelial growth factor receptor (VEGFR)-1 exists in different forms, derived from alternative splicing of the same gene. In addition to the transmembrane form, endothelial cells produce a soluble VEGFR-1 (sVEGFR-1) isoform, whereas non-endothelial cells produce both sVEGFR-1 and a different soluble molecule, known as soluble fms-like tyrosine kinase (sFlt)1-14. By binding members of the vascular endothelial growth factor (VEGF) family, the soluble forms reduce the amounts of VEGFs available for the interaction with their transmembrane receptors, thereby negatively regulating VEGFR-mediated signaling. In agreement with this activity, high levels of circulating sVEGFR-1 or sFlt1-14 are associated with different pathological conditions involving vascular dysfunction. Moreover, sVEGFR-1 and sFlt1-14 have an additional role in angiogenesis: they are deposited in the endothelial cell and pericyte extracellular matrix, and interact with cell membrane components. Interaction of sVEGFR-1 with α5β1 integrin on endothelial cell membranes regulates vessel growth, triggering a dynamic, pro-angiogenic phenotype. Interaction of sVEGFR-1/sFlt1-14 with cell membrane glycosphingolipids in lipid rafts controls kidney cell morphology and glomerular barrier functions. These cell⁻matrix contacts represent attractive novel targets for pharmacological intervention in addition to those addressing interactions between VEGFs and their receptors.
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Affiliation(s)
| | - Miriam Carbo
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University, 00185 Rome, Italy.
| | - Veronica Morea
- National Research Council of Italy (CNR), Department of Biochemical Sciences "A. Rossi Fanelli", Institute of Molecular Biology and Pathology c/o, Sapienza University, 00185 Rome, Italy.
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Miller MA, Sullivan RJ, Lauffenburger DA. Molecular Pathways: Receptor Ectodomain Shedding in Treatment, Resistance, and Monitoring of Cancer. Clin Cancer Res 2016; 23:623-629. [PMID: 27895032 DOI: 10.1158/1078-0432.ccr-16-0869] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/01/2016] [Accepted: 11/01/2016] [Indexed: 12/21/2022]
Abstract
Proteases known as sheddases cleave the extracellular domains of their substrates from the cell surface. The A Disintegrin and Metalloproteinases ADAM10 and ADAM17 are among the most prominent sheddases, being widely expressed in many tissues, frequently overexpressed in cancer, and promiscuously cleaving diverse substrates. It is increasingly clear that the proteolytic shedding of transmembrane receptors impacts pathophysiology and drug response. Receptor substrates of sheddases include the cytokine receptors TNFR1 and IL6R; the Notch receptors; type-I and -III TGFβ receptors; receptor tyrosine kinases (RTK) such as HER2, HER4, and VEGFR2; and, in particular, MET and TAM-family RTKs AXL and Mer (MerTK). Activation of receptor shedding by mechanical cues, hypoxia, radiation, and phosphosignaling offers insight into mechanisms of drug resistance. This particularly holds for kinase inhibitors targeting BRAF (such as vemurafenib and dabrafenib) and MEK (such as trametinib and cobimetinib), along with direct sheddase inhibitors. Receptor proteolysis can be detected in patient fluids and is especially relevant in melanoma, glioblastoma, lung cancer, and triple-negative breast cancer where RTK substrates, MAPK signaling, and ADAMs are frequently dysregulated. Translatable strategies to exploit receptor shedding include combination kinase inhibitor regimens, recombinant decoy receptors based on endogenous counterparts, and, potentially, immunotherapy. Clin Cancer Res; 23(3); 623-9. ©2016 AACR.
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Affiliation(s)
- Miles A Miller
- Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Ryan J Sullivan
- Division of Medical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, Massachusetts
| | - Douglas A Lauffenburger
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts.
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Ectodomain cleavage of FLT1 regulates receptor activation and function and is not required for its downstream intracellular cleavage. Exp Cell Res 2016; 344:103-111. [PMID: 27017929 DOI: 10.1016/j.yexcr.2016.03.020] [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: 01/21/2016] [Revised: 03/18/2016] [Accepted: 03/22/2016] [Indexed: 01/18/2023]
Abstract
FLT1 is a cell surface VEGF receptor which is cleaved to release an N-terminal ectodomain which binds VEGF and PlGF and can antagonize the effects of VEGF in the extracellular milieu. To further evaluate FLT1 processing we expressed tagged FLT1 constructs in HEK293 and COS7 cells where we demonstrate, by deletion mapping, that the cleavage site is immediately adjacent to the transmembrane domain (TMD) between residues 759 and 763. Cleavage reciprocally regulates free VEGF in conditioned media and we show that the cleavage site is also transferable to another transmembrane receptor. A second cleavage event downstream of the ectodomain cleavage releases a cytosolic C-terminal FLT1 fragment and this intracellular cleavage of FLT1 is not catalyzed or regulated by the upstream ectodomain cleavage since abolition of the ectodomain cleavage has no impact on the downstream cleavage event. The downstream cleavage event is not susceptible to γ-secretase inhibitors and overexpression of presenilin 1, the catalytic subunit of γ-secretase did not change the downstream intracellular cleavage event. Furthermore, this cleavage did not occur via a previously published valine residue (767V) in the TMD of FLT1, indicating the existence of another cleavage pathway. We tested the impact of the ectodomain cleavage on p44/42 MAP kinase activation and demonstrate that compared to wild type FLT1, cleavage resistant FLT1 constructs failed to stimulate p44/42 MAP kinase activation. Our results indicate that FLT1 ectodomain cleavage not only regulates the availability of free VEGF in the extracellular milieu but also regulates cellular signaling via the ERK kinase pathway.
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Smith G, Tomlinson D, Harrison M, Ponnambalam S. Chapter Eight - Ubiquitin-Mediated Regulation of Cellular Responses to Vascular Endothelial Growth Factors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 141:313-38. [DOI: 10.1016/bs.pmbts.2016.02.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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The cellular response to vascular endothelial growth factors requires co-ordinated signal transduction, trafficking and proteolysis. Biosci Rep 2015; 35:BSR20150171. [PMID: 26285805 PMCID: PMC4613718 DOI: 10.1042/bsr20150171] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/18/2015] [Indexed: 01/18/2023] Open
Abstract
VEGFs (vascular endothelial growth factors) are a family of conserved disulfide-linked soluble secretory glycoproteins found in higher eukaryotes. VEGFs mediate a wide range of responses in different tissues including metabolic homoeostasis, cell proliferation, migration and tubulogenesis. Such responses are initiated by VEGF binding to soluble and membrane-bound VEGFRs (VEGF receptor tyrosine kinases) and co-receptors. VEGF and receptor splice isoform diversity further enhances complexity of membrane protein assembly and function in signal transduction pathways that control multiple cellular responses. Different signal transduction pathways are simultaneously activated by VEGFR-VEGF complexes with membrane trafficking along the endosome-lysosome network further modulating signal output from multiple enzymatic events associated with such pathways. Balancing VEGFR-VEGF signal transduction with trafficking and proteolysis is essential in controlling the intensity and duration of different intracellular signalling events. Dysfunction in VEGF-regulated signal transduction is important in chronic disease states including cancer, atherosclerosis and blindness. This family of growth factors and receptors is an important model system for understanding human disease pathology and developing new therapeutics for treating such ailments.
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Han KY, Dugas-Ford J, Lee H, Chang JH, Azar DT. MMP14 Cleavage of VEGFR1 in the Cornea Leads to a VEGF-Trap Antiangiogenic Effect. Invest Ophthalmol Vis Sci 2015; 56:5450-6. [PMID: 26284550 PMCID: PMC4544186 DOI: 10.1167/iovs.14-16248] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 05/28/2015] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To determine the possible antiangiogenic effect of metalloproteinase (MMP) 14 cleavage of vascular endothelial growth factor receptor 1 (VEGFR1) in the cornea. METHODS Recombinant mouse (rm) VEGFR1 was incubated with various concentrations of recombinant MMP14 to examine proteolysis in vitro. The reaction mixture was analyzed by SDS-PAGE and stained with Coomassie blue. The fragments resulting from rmVEGFR1 cleavage by MMP14 were subjected to Edman degradation, and the amino acid sequences were aligned with rmVEGFR1 sequences. Surface plasmon resonance was used to determine the equilibrium dissociation constant (KD) between MMP14 and rmVEGFR1. The KD value of rmVEGFR1 and the 59.8-kDa cleavage product binding to VEGF-A₁₆₅ was also determined. Cell proliferation assays were performed in the presence of VEGF-A₁₆₅ plus the 59.8-kDa VEGFR1 fragment or VEGF-A₁₆₅ alone. RESULTS Matrix metalloproteinase 14 binds and cleaves rmVEGFR1 to produce 59.8-kDa (N-terminal fragment, Ig domains 1-5), 35-kDa (C-terminal fragment containing IgG and His-tag), and 21-kDa (Ig domains 6-7) fragments. The 59.8-kDa fragment showed binding to VEGF-A₁₆₅ and inhibited VEGF-induced endothelial cell mitogenesis. CONCLUSIONS Our findings suggest that VEGFR1 cleavage by MMP14 in the cornea leads to a VEGF-trap effect, reducing the proangiogenic effect of VEGF-A₁₆₅, thereby reducing corneal angiogenesis.
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Affiliation(s)
- Kyu-Yeon Han
- Department of Ophthalmology and Visual Sciences Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Jennifer Dugas-Ford
- Department of Ophthalmology and Visual Sciences Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Hyun Lee
- Center for Pharmaceutical Biotechnology and Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Jin-Hong Chang
- Department of Ophthalmology and Visual Sciences Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Dimitri T. Azar
- Department of Ophthalmology and Visual Sciences Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, Illinois, United States
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Smith GA, Fearnley GW, Harrison MA, Tomlinson DC, Wheatcroft SB, Ponnambalam S. Vascular endothelial growth factors: multitasking functionality in metabolism, health and disease. J Inherit Metab Dis 2015; 38:753-63. [PMID: 25868665 DOI: 10.1007/s10545-015-9838-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/06/2015] [Accepted: 03/11/2015] [Indexed: 10/23/2022]
Abstract
Vascular endothelial growth factors (VEGFs) bind to VEGF receptor tyrosine kinases (VEGFRs). The VEGF and VEGFR gene products regulate diverse regulatory pathways in mammalian development, health and disease. The interaction between a particular VEGF and its cognate VEGFR activates multiple signal transduction pathways which regulate different cellular responses including metabolism, gene expression, proliferation, migration, and survival. The family of VEGF isoforms regulate vascular physiology and promote tissue homeostasis. VEGF dysfunction is implicated in major chronic disease states including atherosclerosis, diabetes, and cancer. More recent studies implicate a strong link between response to VEGF and regulation of vascular metabolism. Understanding how this family of multitasking cytokines regulates cell and animal function has implications for treating many different diseases.
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Affiliation(s)
- Gina A Smith
- Endothelial Cell Biology Unit, School of Molecular & Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
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Li C, Raikwar NS, Santillan MK, Santillan DA, Thomas CP. Aspirin inhibits expression of sFLT1 from human cytotrophoblasts induced by hypoxia, via cyclo-oxygenase 1. Placenta 2015; 36:446-53. [PMID: 25638730 DOI: 10.1016/j.placenta.2015.01.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 12/29/2014] [Accepted: 01/08/2015] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Elevated circulating soluble FLT1 (sFLT1) levels seen in preeclampsia may play a role in its development. Aspirin is recommended for prevention of preeclampsia. We hypothesized that aspirin may inhibit the production of sFlt1. METHODS Placentas from women with and without preeclampsia were collected. Primary cytotrophoblasts (CTBs) were cultured from normal placentas and treated with aspirin, sc-560, a COX1 inhibitor or celecoxib, a COX2 inhibitor. The expression of sFLT1, FLT1, COX1 and COX2 was studied. The effect of aspirin on sFlt1 expression was also studied in HEK293 cells and in HTR-8/SVNeo cells. RESULTS The expression of sFLT1 was increased in preeclamptic placentas compared to control placentas and the expression and release of sFLT1 increased in CTBs exposed to 2% O2 compared to controls. Aspirin at 3 and 12 mM concentration reduced the expression and release of sFLT1 in CTBs. Aspirin also inhibited sFlt1 expression from HTR-8/SVNeo and HEK293 cells. Sc-560, but not celecoxib, reduced sFLT1 expression and release from CTBs. Aspirin and sc-560 also reduced hypoxia-induced FLT1 mRNA expression and inhibited COX1 mRNA in CTBs. DISCUSSION This study confirms that sFLT1 expression is increased in preeclamptic placentas and in CTBs exposed to hypoxia. Aspirin inhibits the production sFLT1 in CTBs and in HTR-8/SVNeo. Sc-560 recapitulated the effects of aspirin on sFLT1 expression and release in CTBs suggesting that the aspirin effect may be mediated via inhibition of COX1. The study increases our understanding of the mechanisms regulating sFlt1 expression and provides a plausible explanation for the effect of aspirin to prevent preeclampsia.
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Affiliation(s)
- C Li
- Department of Obstetrics and Gynecology, Iowa City, IA, USA
| | - N S Raikwar
- Division of Nephrology, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - M K Santillan
- Department of Obstetrics and Gynecology, Iowa City, IA, USA
| | - D A Santillan
- Department of Obstetrics and Gynecology, Iowa City, IA, USA
| | - C P Thomas
- Department of Obstetrics and Gynecology, Iowa City, IA, USA; Division of Nephrology, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Veterans Affairs Medical Center, Iowa City, IA, USA.
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Raikwar NS, Liu KZ, Thomas CP. N-terminal cleavage and release of the ectodomain of Flt1 is mediated via ADAM10 and ADAM 17 and regulated by VEGFR2 and the Flt1 intracellular domain. PLoS One 2014; 9:e112794. [PMID: 25387128 PMCID: PMC4227870 DOI: 10.1371/journal.pone.0112794] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 10/20/2014] [Indexed: 11/25/2022] Open
Abstract
Flt is one of the cell surface VEGF receptors which can be cleaved to release an N-terminal extracellular fragment which, like alternately transcribed soluble Flt1 (sFlt1), can antagonize the effects of VEGF. In HUVEC and in HEK293 cells where Flt1 was expressed, metalloprotease inhibitors reduced Flt1 N-terminal cleavage. Overexpression of ADAM10 and ADAM17 increased cleavage while knockdown of ADAM10 and ADAM17 reduced N-terminal cleavage suggesting that these metalloproteases were responsible for Flt1 cleavage. Protein kinase C (PKC) activation increased the abundance and the cleavage of Flt1 but this did not require any residues within the intracellular portion of Flt1. ALLN, a proteasomal inhibitor, increased the abundance of Flt1 which was additive to the effect of PKC. Removal of the entire cytosolic region of Flt1 appeared to stimulate cleavage of Flt1 and Flt1 was no longer sensitive to ALLN suggesting that the cytosolic region contained a degradation domain. Knock down of c-CBL, a ring finger ubiquitin ligase, in HEK293 cells increased the expression of Flt1 although it did not appear to require a previously published tyrosine residue (1333Y) in the C-terminus of Flt1. Increasing VEGFR2 expression increased VEGF-stimulated sFlt1 expression and progressively reduced the cleavage of Flt1 with Flt1 staying bound to VEGFR2 as a heterodimer. Our results imply that secreted sFlt1 and cleaved Flt1 will tend to have local effects as a VEGF antagonist when released from cells expressing VEGFR2 and more distant effects when released from cells lacking VEGFR2.
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Affiliation(s)
- Nandita S. Raikwar
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, IA, United States of America
| | - Kang Z. Liu
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, IA, United States of America
| | - Christie P. Thomas
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, IA, United States of America
- Department of Pediatrics, University of Iowa College of Medicine, Iowa City, IA, United States of America
- Department of Obstetrics, University of Iowa College of Medicine, Iowa City, IA, United States of America
- Department of Molecular and Cellular Biology, University of Iowa College of Medicine, Iowa City, IA, United States of America
- Veterans Affairs Medical Center, Iowa City, IA, United States of America
- * E-mail:
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Unlocking Doors without Keys: Activation of Src by Truncated C-terminal Intracellular Receptor Tyrosine Kinases Lacking Tyrosine Kinase Activity. Cells 2014; 3:92-111. [PMID: 24709904 PMCID: PMC3980740 DOI: 10.3390/cells3010092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 02/07/2014] [Accepted: 02/07/2014] [Indexed: 01/07/2023] Open
Abstract
One of the best examples of the renaissance of Src as an open door to cancer has been the demonstration that just five min of Src activation is sufficient for transformation and also for induction and maintenance of cancer stem cells [1]. Many tyrosine kinase receptors, through the binding of their ligands, become the keys that unlock the structure of Src and activate its oncogenic transduction pathways. Furthermore, intracellular isoforms of these receptors, devoid of any tyrosine kinase activity, still retain the ability to unlock Src. This has been shown with a truncated isoform of KIT (tr-KIT) and a truncated isoform of VEGFR-1 (i21-VEGFR-1), which are intracellular and require no ligand binding, but are nonetheless able to activate Src and induce cell migration and invasion of cancer cells. Expression of the i21-VEGFR-1 is upregulated by the Notch signaling pathway and repressed by miR-200c and retinoic acid in breast cancer cells. Both Notch inhibitors and retinoic acid have been proposed as potential therapies for invasive breast cancer.
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