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Apaydin T, Zonis S, Zhou C, Valencia CW, Barrett R, Strous GJ, Mol JA, Chesnokova V, Melmed S. WIP1 is a novel specific target for growth hormone action. iScience 2023; 26:108117. [PMID: 37876819 PMCID: PMC10590974 DOI: 10.1016/j.isci.2023.108117] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/22/2023] [Accepted: 09/29/2023] [Indexed: 10/26/2023] Open
Abstract
DNA damage repair (DDR) is mediated by phosphorylating effectors ATM kinase, CHK2, p53, and γH2AX. We showed earlier that GH suppresses DDR by suppressing pATM, resulting in DNA damage accumulation. Here, we show GH acting through GH receptor (GHR) inducing wild-type p53-inducible phosphatase 1 (WIP1), which dephosphorylated ATM and its effectors in normal human colon cells and three-dimensional human intestinal organoids. Mice bearing GH-secreting xenografts exhibited induced colon WIP1 with suppressed pATM and γH2AX. WIP1 was also induced in buffy coats derived from patients with elevated GH from somatotroph adenomas. In contrast, decreased colon WIP1 was observed in GHR-/- mice. WIP1 inhibition restored ATM phosphorylation and reversed GH-induced DNA damage. We elucidated a novel GH signaling pathway activating Src/AMPK to trigger HIPK2 nuclear-cytoplasmic relocation and suppressing WIP1 ubiquitination. Concordantly, blocking either AMPK or Src abolished GH-induced WIP1. We identify WIP1 as a specific target for GH-mediated epithelial DNA damage accumulation.
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Affiliation(s)
- Tugce Apaydin
- Department of Medicine, Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Svetlana Zonis
- Department of Medicine, Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Cuiqi Zhou
- Department of Medicine, Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Christian Wong Valencia
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Robert Barrett
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ger J. Strous
- Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
| | - Jan A. Mol
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, the Netherlands
| | - Vera Chesnokova
- Department of Medicine, Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Shlomo Melmed
- Department of Medicine, Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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Yan H, Wang H, Yin Y, Zou J, Xiao F, Yi L, He Y, He B. GHR is involved in gastric cell growth and apoptosis via PI3K/AKT signalling. J Cell Mol Med 2021; 25:2450-2458. [PMID: 33492754 PMCID: PMC7933969 DOI: 10.1111/jcmm.16160] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 11/05/2020] [Accepted: 11/20/2020] [Indexed: 02/06/2023] Open
Abstract
Growth hormone receptor (GHR), the cognate receptor of growth hormone (GH), is a membrane bound receptor that belongs to the class I cytokine receptor superfamily. GH binding GHR induces cell differentiation and maturation, initiates the anabolism inside the cells and promotes cell proliferation. Recently, GHR has been reported to be associated with various types of cancer. However, the underlying mechanism of GHR in gastric cancer has not been defined. Our results showed that silence of GHR inhibited the growth of SGC-7901 and MGC-803 cells, and tumour development in mouse xenograft model. Flow cytometry showed that GHR knockout significantly stimulated gastric cancer cell apoptosis and caused G1 cell cycle arrest, which was also verified by Western blot that GHR deficiency induced the protein level of cleaved-PARP, a valuable marker of apoptosis. In addition, GHR deficiency inhibited the activation of PI3K/AKT signalling pathway. On the basis of the results, that GHR regulates gastric cancer cell growth and apoptosis through controlling G1 cell cycle progression via mediating PI3K/AKT signalling pathway. These findings provide a novel understanding for the role of GHR in gastric cancer.
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Affiliation(s)
- Hong‐Zhu Yan
- Department of PathologySeventh People's Hospital of Shanghai University of TCMShanghaiChina
| | - Hua‐Feng Wang
- Department of PathologyRuijin Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yueling Yin
- Department of PathologyHaiyang People's HospitalHaiyangChina
| | - Jue Zou
- Department of PathologySeventh People's Hospital of Shanghai University of TCMShanghaiChina
| | - Feng Xiao
- Department of PathologySeventh People's Hospital of Shanghai University of TCMShanghaiChina
| | - Li‐Na Yi
- Department of PathologySeventh People's Hospital of Shanghai University of TCMShanghaiChina
| | - Ying He
- Department of UltrasoundThe Tumor Hospital of Nantong UniversityNantongChina
| | - Bo‐Sheng He
- Department of RadiologyAffiliated Hospital 2 of Nantong UniversityNantongChina
- Clinical Medicine Research CenterAffiliated Hospital 2 of Nantong UniversityNantongChina
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Strous GJ, Almeida ADS, Putters J, Schantl J, Sedek M, Slotman JA, Nespital T, Hassink GC, Mol JA. Growth Hormone Receptor Regulation in Cancer and Chronic Diseases. Front Endocrinol (Lausanne) 2020; 11:597573. [PMID: 33312162 PMCID: PMC7708378 DOI: 10.3389/fendo.2020.597573] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 10/14/2020] [Indexed: 12/14/2022] Open
Abstract
The GHR signaling pathway plays important roles in growth, metabolism, cell cycle control, immunity, homeostatic processes, and chemoresistance via both the JAK/STAT and the SRC pathways. Dysregulation of GHR signaling is associated with various diseases and chronic conditions such as acromegaly, cancer, aging, metabolic disease, fibroses, inflammation and autoimmunity. Numerous studies entailing the GHR signaling pathway have been conducted for various cancers. Diverse factors mediate the up- or down-regulation of GHR signaling through post-translational modifications. Of the numerous modifications, ubiquitination and deubiquitination are prominent events. Ubiquitination by E3 ligase attaches ubiquitins to target proteins and induces proteasomal degradation or starts the sequence of events that leads to endocytosis and lysosomal degradation. In this review, we discuss the role of first line effectors that act directly on the GHR at the cell surface including ADAM17, JAK2, SRC family member Lyn, Ubc13/CHIP, proteasome, βTrCP, CK2, STAT5b, and SOCS2. Activity of all, except JAK2, Lyn and STAT5b, counteract GHR signaling. Loss of their function increases the GH-induced signaling in favor of aging and certain chronic diseases, exemplified by increased lung cancer risk in case of a mutation in the SOCS2-GHR interaction site. Insight in their roles in GHR signaling can be applied for cancer and other therapeutic strategies.
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Affiliation(s)
- Ger J. Strous
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
- BIMINI Biotech B.V., Leiden, Netherlands
| | - Ana Da Silva Almeida
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Joyce Putters
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Julia Schantl
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Magdalena Sedek
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Johan A. Slotman
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Tobias Nespital
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Gerco C. Hassink
- Department of Cell Biology, Centre for Molecular Medicine, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Jan A. Mol
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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4
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Lu M, Flanagan JU, Langley RJ, Hay MP, Perry JK. Targeting growth hormone function: strategies and therapeutic applications. Signal Transduct Target Ther 2019; 4:3. [PMID: 30775002 PMCID: PMC6367471 DOI: 10.1038/s41392-019-0036-y] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 01/12/2023] Open
Abstract
Human growth hormone (GH) is a classical pituitary endocrine hormone that is essential for normal postnatal growth and has pleiotropic effects across multiple physiological systems. GH is also expressed in extrapituitary tissues and has localized autocrine/paracrine effects at these sites. In adults, hypersecretion of GH causes acromegaly, and strategies that block the release of GH or that inhibit GH receptor (GHR) activation are the primary forms of medical therapy for this disease. Overproduction of GH has also been linked to cancer and the microvascular complications that are associated with diabetes. However, studies to investigate the therapeutic potential of GHR antagonism in these diseases have been limited, most likely due to difficulty in accessing therapeutic tools to study the pharmacology of the receptor in vivo. This review will discuss current and emerging strategies for antagonizing GH function and the potential disease indications. Emerging therapies are offering an expanded toolkit for combatting the effects of human growth hormone overproduction. Human growth hormone (GH) is a major driver of postnatal growth; however, systemic or localized overproduction is implicated in the aberrant growth disease acromegaly, cancer, and diabetes. In this review, researchers led by Jo Perry, from the University of Auckland, New Zealand, discuss strategies that either inhibit GH production, block its systemic receptor, or interrupt its downstream signaling pathways. The only licensed GH receptor blocker is pegvisomant, but therapies are in development that include long-acting protein and antibody-based blockers, and nucleotide complexes that degrade GHR production have also shown promise. Studies investigating GHR antagonism are limited, partly due to difficulty in accessing therapeutic tools which block GHR function, but overcoming these obstacles may yield advances in alleviating chronic disease.
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Affiliation(s)
- Man Lu
- 1Liggins Institute, University of Auckland, Auckland, New Zealand
| | - Jack U Flanagan
- 2Auckland Cancer Society Research Centre, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,3Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Ries J Langley
- 3Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.,4Department of Molecular Medicine and Pathology, School of Medical Sciences, University of Auckland, Auckland, New Zealand
| | - Michael P Hay
- 2Auckland Cancer Society Research Centre, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,3Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Jo K Perry
- 1Liggins Institute, University of Auckland, Auckland, New Zealand.,3Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
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5
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Amyloid formation of growth hormone in presence of zinc: Relevance to its storage in secretory granules. Sci Rep 2016; 6:23370. [PMID: 27004850 PMCID: PMC4804206 DOI: 10.1038/srep23370] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 03/04/2016] [Indexed: 11/16/2022] Open
Abstract
Amyloids are cross-β-sheet fibrillar aggregates, associated with various human diseases and native functions such as protein/peptide hormone storage inside secretory granules of neuroendocrine cells. In the current study, using amyloid detecting agents, we show that growth hormone (GH) could be stored as amyloid in the pituitary of rat. Moreover, to demonstrate the formation of GH amyloid in vitro, we studied various conditions (solvents, glycosaminoglycans, salts and metal ions) and found that in presence of zinc metal ions (Zn(II)), GH formed short curvy fibrils. The amyloidogenic nature of these fibrils was examined by Thioflavin T binding, Congo Red binding, transmission electron microscopy and X-ray diffraction. Our biophysical studies also suggest that Zn(II) initiates the early oligomerization of GH that eventually facilitates the fibrillation process. Furthermore, using immunofluorescence study of pituitary tissue, we show that GH in pituitary significantly co-localizes with Zn(II), suggesting the probable role of zinc in GH aggregation within secretory granules. We also found that GH amyloid formed in vitro is capable of releasing monomers. The study will help to understand the possible mechanism of GH storage, its regulation and monomer release from the somatotrophs of anterior pituitary.
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Yu J, Zhao L, Wang A, Eleswarapu S, Ge X, Chen D, Jiang H. Growth hormone stimulates transcription of the fibroblast growth factor 21 gene in the liver through the signal transducer and activator of transcription 5. Endocrinology 2012; 153:750-8. [PMID: 22166977 DOI: 10.1210/en.2011-1591] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is a recently discovered metabolic regulator. Interestingly, FGF21 is also known to inhibit Janus kinase 2 (JAK2)-signal transducer and activator of transcription 5 (STAT5) signaling from the GH receptor in the liver, where FGF21 mRNA is predominantly expressed. In this study, we tested the hypothesis that FGF21 gene expression in the liver is controlled by GH through STAT5. We found that GH injection to cattle increased FGF21 mRNA expression in the liver. Mapped by a 5'-rapid amplification of cDNA ends assay, transcription of the FGF21 gene in the bovine liver was mainly initiated from a nucleotide 24 bp downstream of a TATA box. The bovine FGF21 promoter contains three putative STAT5-binding sites. EMSA confirmed the ability of them to bind to liver STAT5 protein from GH-injected cattle. Chromatin immunoprecipitation assays demonstrated that GH administration increased the binding of STAT5 to the FGF21 promoter in the liver. Cotransfection analyses showed that GH induced reporter gene expression from the FGF21 promoter in a STAT5-dependent manner. GH also stimulated FGF21 mRNA expression in cultured mouse hepatocytes. These data together indicate that GH directly stimulates FGF21 gene transcription in the liver, at least in part, through STAT5. This finding, together with the fact that FGF21 inhibits GH-induced JAK2-STAT5 signaling in the liver, suggests a novel negative feedback loop that prevents excessive JAK2-STAT5 signaling from the GH receptor in the liver.
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Affiliation(s)
- Jie Yu
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
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8
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Sun H, Lin CH, Smith ME. Growth hormone promotes hair cell regeneration in the zebrafish (Danio rerio) inner ear following acoustic trauma. PLoS One 2011; 6:e28372. [PMID: 22140580 PMCID: PMC3227666 DOI: 10.1371/journal.pone.0028372] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 11/07/2011] [Indexed: 01/13/2023] Open
Abstract
Background Previous microarray analysis showed that growth hormone (GH) was significantly upregulated following acoustic trauma in the zebrafish (Danio rerio) ear suggesting that GH may play an important role in the process of auditory hair cell regeneration. Our objective was to examine the effects of exogenous and endogenous GH on zebrafish inner ear epithelia following acoustic trauma. Methodology/Principal Findings We induced auditory hair cell damage by exposing zebrafish to acoustic overstimulation. Fish were then injected intraperitoneally with either carp GH or buffer, and placed in a recovery tank for either one or two days. Phalloidin-, bromodeoxyuridine (BrdU)-, and TUNEL-labeling were used to examine hair cell densities, cell proliferation, and apoptosis, respectively. Two days post-trauma, saccular hair cell densities in GH-treated fish were similar to that of baseline controls, whereas buffer-injected fish showed significantly reduced densities of hair cell bundles. Cell proliferation was greater and apoptosis reduced in the saccules, lagenae, and utricles of GH-treated fish one day following trauma compared to controls. Fluorescent in situ hybridization (FISH) was used to examine the localization of GH mRNA in the zebrafish ear. At one day post-trauma, GH mRNA expression appeared to be localized perinuclearly around erythrocytes in the blood vessels of the inner ear epithelia. In order to examine the effects of endogenous GH on the process of cell proliferation in the ear, a GH antagonist was injected into zebrafish immediately following acoustic trauma, resulting in significantly decreased cell proliferation one day post-trauma in all three zebrafish inner ear end organs. Conclusions/Significance Our results show that exogenous GH promotes post-trauma auditory hair cell regeneration in the zebrafish ear through stimulating proliferation and suppressing apoptosis, and that endogenous GH signals are present in the zebrafish ear during the process of auditory hair cell regeneration.
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Affiliation(s)
- Huifang Sun
- Department of Biology and Biotechnology Center, Western Kentucky University, Bowling Green, Kentucky, United States of America
| | - Chia-Hui Lin
- Department of Biology and Biotechnology Center, Western Kentucky University, Bowling Green, Kentucky, United States of America
| | - Michael E. Smith
- Department of Biology and Biotechnology Center, Western Kentucky University, Bowling Green, Kentucky, United States of America
- * E-mail:
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Carew RM, Sadagurski M, Goldschmeding R, Martin F, White MF, Brazil DP. Deletion of Irs2 causes reduced kidney size in mice: role for inhibition of GSK3beta? BMC DEVELOPMENTAL BIOLOGY 2010; 10:73. [PMID: 20604929 PMCID: PMC2910663 DOI: 10.1186/1471-213x-10-73] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Accepted: 07/06/2010] [Indexed: 11/10/2022]
Abstract
BACKGROUND Male Irs2-/- mice develop fatal type 2 diabetes at 13-14 weeks. Defects in neuronal proliferation, pituitary development and photoreceptor cell survival manifest in Irs2-/- mice. We identify retarded renal growth in male and female Irs2-/- mice, independent of diabetes. RESULTS Kidney size and kidney:body weight ratio were reduced by approximately 20% in Irs2-/- mice at postnatal day 5 and was maintained in maturity. Reduced glomerular number but similar glomerular density was detected in Irs2-/- kidney compared to wild-type, suggesting intact global kidney structure. Analysis of insulin signalling revealed renal-specific upregulation of PKBbeta/Akt2, hyperphosphorylation of GSK3beta and concomitant accumulation of beta-catenin in Irs2-/- kidney. Despite this, no significant upregulation of beta-catenin targets was detected. Kidney-specific increases in Yes-associated protein (YAP), a key driver of organ size were also detected in the absence of Irs2. YAP phosphorylation on its inhibitory site Ser127 was also increased, with no change in the levels of YAP-regulated genes, suggesting that overall YAP activity was not increased in Irs2-/- kidney. CONCLUSIONS In summary, deletion of Irs2 causes reduced kidney size early in mouse development. Compensatory mechanisms such as increased beta-catenin and YAP levels failed to overcome this developmental defect. These data point to Irs2 as an important novel mediator of kidney size.
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Affiliation(s)
- Rosemarie M Carew
- UCD Diabetes Research Centre, UCD Conway Institute, School of Medicine and Medical Science, University College Dublin, Belfield Dublin 4, Ireland
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Fradkin AH, Boand CS, Eisenberg SP, Rosendahl MS, Randolph TW. Recombinant murine growth hormone from E. coli inclusion bodies: Expression, high-pressure solubilization and refolding, and characterization of activity and structure. Biotechnol Prog 2010; 26:743-9. [DOI: 10.1002/btpr.393] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Perry JK, Mohankumar KM, Emerald BS, Mertani HC, Lobie PE. The contribution of growth hormone to mammary neoplasia. J Mammary Gland Biol Neoplasia 2008; 13:131-45. [PMID: 18253708 PMCID: PMC2665193 DOI: 10.1007/s10911-008-9070-z] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Accepted: 01/02/2008] [Indexed: 12/13/2022] Open
Abstract
While the effects of growth hormone (GH) on longitudinal growth are well established, the observation that GH contributes to neoplastic progression is more recent. Accumulating literature implicates GH-mediated signal transduction in the development and progression of a wide range malignancies including breast cancer. Recently autocrine human GH been demonstrated to be an orthotopically expressed oncogene for the human mammary gland. This review will highlight recent evidence linking GH and mammary carcinoma and discuss GH-antagonism as a potential therapeutic approach for treatment of breast cancer.
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Affiliation(s)
- Jo K Perry
- The Liggins Institute and the National Research Centre for Growth and Development
University of Auckland2-6 Park Avenue, Grafton, Private Bag 92019, Auckland 1023,NZ
| | - Kumarasamypet M Mohankumar
- The Liggins Institute and the National Research Centre for Growth and Development
University of Auckland2-6 Park Avenue, Grafton, Private Bag 92019, Auckland 1023,NZ
| | - B Starling Emerald
- The Liggins Institute and the National Research Centre for Growth and Development
University of Auckland2-6 Park Avenue, Grafton, Private Bag 92019, Auckland 1023,NZ
| | - Hichem C Mertani
- PICM, Physiologie intégrative, cellulaire et moléculaire
CNRS : UMR5123Université Claude Bernard - Lyon IBât. R. Dubois
43, Bvd du 11 Novembre 1918
69622 VILLEURBANNE CEDEX,FR
| | - Peter E Lobie
- The Liggins Institute and the National Research Centre for Growth and Development
University of Auckland2-6 Park Avenue, Grafton, Private Bag 92019, Auckland 1023,NZ
- Department of Molecular Medicine and Pathology
University of AucklandFaculty of Medical and Health Sciences, Private Bag 92019, Auckland, New Zealand,NZ
- * Correspondence should be adressed to: Peter E Lobie
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12
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Harvey S, Martin BT, Baudet ML, Davis P, Sauve Y, Sanders EJ. Growth hormone in the visual system: comparative endocrinology. Gen Comp Endocrinol 2007; 153:124-31. [PMID: 17303134 DOI: 10.1016/j.ygcen.2006.12.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2006] [Revised: 11/21/2006] [Accepted: 12/25/2006] [Indexed: 01/09/2023]
Abstract
Growth hormone (GH) is rarely considered to be involved in ocular development or vision or to be present in the visual system. Basic and clinical studies nevertheless support roles for GH in the ocular function of most vertebrate groups and for its extrapituitary production in ocular tissues. The comparative endocrinology of endocrine, autocrine or paracrine GH in the visual system of vertebrates is the focus of this brief review.
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Affiliation(s)
- Steve Harvey
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7.
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13
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van den Eijnden MJ, Strous GJ. Autocrine growth hormone: effects on growth hormone receptor trafficking and signaling. Mol Endocrinol 2007; 21:2832-46. [PMID: 17666586 DOI: 10.1210/me.2007-0092] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
GH and GH receptor are expressed in many extrapituitary tissues, permitting autocrine/paracrine activity. Autocrine GH has regulatory functions in embryonic development and cellular differentiation and proliferation and is reported to be involved in the development and metastasis of tumor cells. To understand the principles of transport and signaling of autocrine GH and GH receptor, we used a model system to express both proteins in the same cell. Our experiments show that GH binds the GH receptor immediately after synthesis in the endoplasmic reticulum and facilitates maturation of GH receptor. The hormone-receptor complexes arrive at the cell surface where exogenously added GH is unable to bind these receptors. Autocrine GH activates the GH receptors, but signal transduction occurs only after exiting the endoplasmic reticulum. This model study explains why autocrine GH-producing cells may be insensitive for GH (antagonist) treatment and clarifies autocrine signaling events.
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Affiliation(s)
- Monique J van den Eijnden
- Department of Cell Biology, Institut of Biomembranes, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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14
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Perry JK, Emerald BS, Mertani HC, Lobie PE. The oncogenic potential of growth hormone. Growth Horm IGF Res 2006; 16:277-289. [PMID: 17101287 DOI: 10.1016/j.ghir.2006.09.006] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2006] [Accepted: 09/28/2006] [Indexed: 10/23/2022]
Abstract
A growing body of recent literature indicates that in addition to an essential role in growth and development, growth hormone may also play a more sinister role in oncogenic transformation and neoplastic progression. Here we review the accumulating evidence implicating growth hormone in the development and progression of cancer and describe what is known of the mechanisms utilised by this hormone in neoplastic transformation.
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Affiliation(s)
- Jo K Perry
- The Liggins Institute and the National Research Centre for Growth and Development, University of Auckland, 2-6 Park Avenue, Grafton, Private Bag 92019, Auckland 1023, New Zealand
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15
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Pacher M, Seewald MJ, Mikula M, Oehler S, Mogg M, Vinatzer U, Eger A, Schweifer N, Varecka R, Sommergruber W, Mikulits W, Schreiber M. Impact of constitutive IGF1/IGF2 stimulation on the transcriptional program of human breast cancer cells. Carcinogenesis 2006; 28:49-59. [PMID: 16774935 DOI: 10.1093/carcin/bgl091] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Insulin-like growth factor (IGF) signaling is a key regulator of breast development and breast cancer. We have analyzed the expression of the IGF signaling cascade in 17 human breast cancer and 4 mammary epithelial cell lines. Five cell lines expressed high levels of IGF1 receptor, insulin (INS)/IGF receptor substrate 1, IGF-binding proteins 2 and 4, as well as the estrogen receptor (ESR), indicating a co-activation of IGF and ESR signaling. Next, we stably overexpressed IGF1 and IGF2 in MCF7 breast cancer cells, which did not affect their epithelial characteristics and the expression and localization of the epithelial marker genes E-cadherin and beta-catenin. Conversely, IGF1 and IGF2 overexpression potently increased cellular proliferation rates and the efficiency of tumor formation in mouse xenograft experiments, whereas the resistance to chemotherapeutic drugs such as taxol was unaltered. Expression profiling of overexpressing cells with whole-genome oligonucleotide microarrays revealed that 21 genes were upregulated >2-fold by both IGF1 and IGF2, 9 by IGF1, and 9 by IGF2. Half of the genes found to be upregulated are involved in transport and biosynthesis of amino acids, including several amino acid transport proteins, argininosuccinate and asparagine synthetases, and methionyl-tRNA synthetase. Upregulation of these genes constitutes a novel mechanism apparently contributing to the stimulatory effects of IGF signaling on the global protein synthesis rate. We conclude that the induction of cell proliferation and tumor formation by long-term IGF stimulation may primarily be due to anabolic effects, in particular increased amino acid production and uptake.
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Affiliation(s)
- Margit Pacher
- Department of Obstetrics and Gynecology, Medical University of Vienna, A-1090 Vienna, Austria
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Yu L, Chen X, Liu S, Long Z. Cloning, expression, and biological activity of growth hormone in bullfrog (Rana catesbeiana). Gen Comp Endocrinol 2006; 146:296-303. [PMID: 16442533 DOI: 10.1016/j.ygcen.2005.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Revised: 10/26/2005] [Accepted: 11/14/2005] [Indexed: 11/17/2022]
Abstract
The cDNA (GenBank, AY251538) encoding bullfrog growth hormone (fGH) was cloned by RT-PCR from the total RNA of pituitary glands. Its sequence encoded a putative polypeptide of 215 amino acids, including a signal peptide of 25 amino acids with no change to those of other previous reported bullfrog GHs. The fGH precursor shares 98.1, 96.3, and 95.3% homologies to those of other bullfrog GHs (AAB24792, AAB19428, CAA31038) in amino-acid sequence and its nucleotide sequences of the coding region shares 99.1 and 98.5% homologies to those of previous bullfrog GH genes (S52027 and X12520). The fGH cDNA was also efficiently expressed in Escherichia coli carrying a plasmid pGfGH in which the cDNA was under the control of GST promoter of pGEX1-lambdaT. The expressed fusion protein GST-fGH is comprised about 29.3% of the total cellular protein in such bacteria. The purified GST-fGH cannot only showed a obvious dose-response curve when it reacted with the hepatic membrane receptor proteins from bullfrog, but also significantly increased the body weight and length of bullfrog after twice injection and such effects lasted two or three weeks after the last injection with purified GST-fGH.
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Affiliation(s)
- Lin Yu
- Key Laboratory of Bio-Resource and Eco-environment, Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, PR China
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17
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Xu XQ, Emerald BS, Goh ELK, Kannan N, Miller LD, Gluckman PD, Liu ET, Lobie PE. Gene Expression Profiling to Identify Oncogenic Determinants of Autocrine Human Growth Hormone in Human Mammary Carcinoma. J Biol Chem 2005; 280:23987-4003. [PMID: 15845533 DOI: 10.1074/jbc.m503869200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have exploited a discrepancy in the oncogenic potential of autocrine and exogenous human growth hormone (hGH) in an attempt to identify molecules that could potentially be involved in oncogenic transformation of the human mammary epithelial cell. Microarray analysis of 19,000 human genes identified a subset of 305 genes in a human mammary carcinoma cell line that were remarkably different in their response to autocrine and exogenous hGH. Autocrine and exogenous hGH also regulated 167 common genes. Semiquantitative reverse transcription-PCR confirmed differential regulation of genes by either autocrine or exogenous hGH. Functional analysis of one of the identified autocrine hGH-regulated genes, TFF3, determined that its expression is sufficient to support anchorage-independent growth of human mammary carcinoma cells. Small interfering RNA-mediated knockdown of TFF3 concordantly abrogated anchorage-independent growth of mammary carcinoma cells and abrogated the ability of autocrine hGH to stimulate oncogenic transformation of immortalized human mammary epithelial cells. Further functional characterization of the identified subset of specifically autocrine hGH regulated genes will delineate additional novel oncogenes for the human mammary epithelial cell.
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Affiliation(s)
- Xiu Qin Xu
- Microarray and Expression Genomics, Genome Institute of Singapore, Republic of Singapore
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18
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Grigorian AL, Bustamante JJ, Hernandez P, Martinez AO, Haro LS. Extraordinarily stable disulfide-linked homodimer of human growth hormone. Protein Sci 2005; 14:902-13. [PMID: 15741328 PMCID: PMC2253441 DOI: 10.1110/ps.041048805] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Although a 22-kDa human growth hormone (hGH) is the predicted protein product of the hGH-N gene, a pleiotropic collection of uncharacterized molecular weight and charge isoforms is also produced. Using chromatography and preparative SDS-PAGE under reducing conditions we isolated an unusually stable mercaptoethanol-resistant (MER) 45-kDa hGH. A 5-h incubation at 100 degrees C in the presence of 2-mercaptoethanol was required to convert approximately 90% of MER-45-kDa hGH into a 22-kDa hGH. Other reductants were not as effective in splitting MER-45-kDa hGH. After fracturing MER-45-kDa hGH, the 22-kDa hGH fragments would spontaneously reassociate if the reductant was removed; however, alkylation of cysteine residues prevented their reassociation. Identical amino acid sequences for the first six N-terminal residues were obtained for MER-45-kDa hGH and its 22-kDa hGH cleavage product. Structural identity of MER-45-kDa hGH and 22-kDa hGH was demonstrated by MALDI-TOF mass spectrometry of tryptic digests. MER-45-kDa hGH did not break up upon incubation with EDTA and EGTA. The significance of this work to our understanding of the structure of hGH isoforms is that it demonstrates that MER-45-kDa hGH is not a single chain polypeptide but is instead a homodimer of 22-kDa hGH monomers. The MER-45-kDa hGH dimer is held together by interchain disulfide bonds and not by divalent metal cation bridges. Additionally, MER-45-kDa hGH's interchain disulfide links are exceptionally resistant to reducing agents and thus confer extreme stability to the homodimer.
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Affiliation(s)
- Alexei L Grigorian
- Department of Biology, The University of Texas at San Antonio, 6900 N. Loop 1604 W., San Antonio, TX 78249-0609, USA
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19
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Diaz-Casares A, Leon Y, de la Rosa EJ, Varela-Nieto I. Regulation of Vertebrate Sensory Organ Development: A Scenario for Growth Hormone and Insulin-Like Growth Factors Action. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2005; 567:221-42. [PMID: 16370141 DOI: 10.1007/0-387-26274-1_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Amelia Diaz-Casares
- Instituto de Investigaciones Biomedicas Alberto Sols, Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid, Spain
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20
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Zhu T, Starling-Emerald B, Zhang X, Lee KO, Gluckman PD, Mertani HC, Lobie PE. Oncogenic Transformation of Human Mammary Epithelial Cells by Autocrine Human Growth Hormone. Cancer Res 2005. [DOI: 10.1158/0008-5472.317.65.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The human growth hormone (hGH) gene is expressed in the normal human mammary epithelial cell and its expression increases concomitant with the acquisition of proliferative lesions. Herein we demonstrate that autocrine production of hGH in human mammary carcinoma cells dramatically enhances anchorage-independent growth in a Janus kinase 2–dependent manner. Forced expression of the hGH gene in immortalized human mammary epithelial cells increased proliferation, decreased apoptosis, altered the cellular morphology and resulted in oncogenic transformation. Autocrine hGH was therefore sufficient to support anchorage-independent growth of immortalized human mammary epithelial cells and tumor formation in vivo. Moreover, autocrine hGH disrupted normal mammary acinar architecture with luminal filling and deregulated proliferation in three-dimensional epithelial cell culture. Autocrine hGH utilized homeobox A1 to govern the transcriptional program required for autocrine hGH–stimulated oncogenic transformation of human mammary epithelial cells, including transcriptional up-regulation of c-Myc, cyclin D1, and Bcl-2. Forced expression of a single orthotopically expressed wild-type gene is therefore sufficient for oncogenic transformation of the immortalized human mammary epithelial cell.
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Affiliation(s)
- Tao Zhu
- 1Institute of Molecular and Cell Biology and
| | - B. Starling-Emerald
- 3Liggins Institute and National Research Centre for Growth and Development, University of Auckland, Auckland, New Zealand; and
| | - Xin Zhang
- 2Department of Medicine, National University of Singapore, Singapore, Republic of Singapore
| | - Kok-Onn Lee
- 2Department of Medicine, National University of Singapore, Singapore, Republic of Singapore
| | - Peter D. Gluckman
- 3Liggins Institute and National Research Centre for Growth and Development, University of Auckland, Auckland, New Zealand; and
| | - Hichem C. Mertani
- 4Centre National de la Recherche Scientifique UMR 5578, Physiologies Energetiques Cellulaires et Moléculaires, Université Claude Bernard, Lyon-1, France
| | - Peter E. Lobie
- 1Institute of Molecular and Cell Biology and
- 3Liggins Institute and National Research Centre for Growth and Development, University of Auckland, Auckland, New Zealand; and
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21
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Gagliardi AD, Kuo EYW, Raulic S, Wagner GF, DiMattia GE. Human stanniocalcin-2 exhibits potent growth-suppressive properties in transgenic mice independently of growth hormone and IGFs. Am J Physiol Endocrinol Metab 2005; 288:E92-105. [PMID: 15367391 DOI: 10.1152/ajpendo.00268.2004] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Stanniocalcin (STC)-2 was discovered by its primary amino acid sequence identity to the hormone STC-1. The function of STC-2 has not been examined; thus we generated two lines of transgenic mice overexpressing human (h)STC-2 to gain insight into its potential functions through identification of overt phenotypes. Analysis of mouse Stc2 gene expression indicates that, unlike Stc1, it is not highly expressed during development but exhibits overlapping expression with Stc1 in adult mice, with heart and skeletal muscle exhibiting highest steady-state levels of Stc2 mRNA. Constitutive overexpression of hSTC-2 resulted in pre- and postnatal growth restriction as early as embryonic day 12.5, progressing such that mature hSTC-2-transgenic mice are approximately 45% smaller than wild-type littermates. hSTC-2 overexpression is sometimes lethal; we observed 26-34% neonatal morbidity without obvious dysmorphology. hSTC-2-induced growth retardation is associated with developmental delay, most notably cranial suture formation. Organ allometry studies show that hSTC-2-induced dwarfism is associated with testicular organomegaly and a significant reduction in skeletal muscle mass likely contributing to the dwarf phenotype. hSTC-2-transgenic mice are also hyperphagic, but this does not result in obesity. Serum Ca2+ and PO4 were unchanged in hSTC-2-transgenic mice, although STC-1 can regulate intra- and extracellular Ca2+ in mammals. Interestingly, severe growth retardation induced by hSTC-2 is not associated with a decrease in GH or IGF expression. Consequently, similar to STC-1, STC-2 can act as a potent growth inhibitor and reduce intramembranous and endochondral bone development and skeletal muscle growth, implying that these tissues are specific physiological targets of stanniocalcins.
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Affiliation(s)
- Anthony D Gagliardi
- Department of Biochemistry, Faculty of Medicine and Dentistry, Univeresity of Western Ontario, London Regional Cancer Center, London, Ontario, Canada
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Abstract
This review focuses on the development of GH receptor antagonist as a novel agent for treatment of acromegaly, its mechanism of action and potential areas of use. A brief overview of acromegaly, its diagnosis and existing medical, surgical and radiotherapy options of treatment is necessary to justify the addition of yet another therapeutic modality to the already vast therapeutic armamentarium.
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Affiliation(s)
- Sowmya K Surya
- Division of Endocrinology, University of Michigan Hospitals, 3920 Taubman Center, Box 0354, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA
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Abstract
Cystic fibrosis (CF) is a life-limiting inherited disorder characterised by pulmonary disease, pancreatic dysfunction and symptoms of malnutrition that are all interrelated with low exercise capacity and poor survival rate. Therapy with growth hormone (GH) may improve the reduced dimensional and functional capacity associated with poor nutritional status and catabolism and therefore improve exercise tolerance, quality of life and survival rate in patients with CF. The literature about GH treatment and its effect on exercise tolerance are rather limited, not always consistent and methodological concerns restrict further analysis. GH treatment may have beneficial effects on both growth and exercise tolerance without serious complications in prepubertal children with CF. The observed dimensional changes of the muscular, cardiovascular and pulmonary system seem to improve aerobic exercise capacity and respiratory and peripheral muscle strength. The physiological background of the observed changes is not yet fully understood, therefore, larger-scale studies with an optimised design are required.
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Affiliation(s)
- Matthias Hütler
- Department of Physical Medicine and Rehabilitation, Haukeland University Hospital, Bergen, Norway.
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24
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Schantl JA, Roza M, Van Kerkhof P, Strous GJ. The growth hormone receptor interacts with its sheddase, the tumour necrosis factor-alpha-converting enzyme (TACE). Biochem J 2004; 377:379-84. [PMID: 14519102 PMCID: PMC1223864 DOI: 10.1042/bj20031321] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2003] [Revised: 09/22/2003] [Accepted: 09/30/2003] [Indexed: 11/17/2022]
Abstract
Proteolysis of the GHR (growth hormone receptor) occurs at the cell surface and results in the release of its extracellular domain, the GHBP (growth hormone-binding protein). TACE (tumour necrosis factor-alpha-converting enzyme) has been identified as a putative protease responsible for GHR cleavage. However, GHR-TACE interaction has not been observed until now. Here, we identified TACE in Chinese hamster cells and confirmed processing and cell-surface expression. Interaction between GHR and TACE was only observed after growth hormone binding. As the growth hormone-GHR(2) complex is a poor substrate for TACE, we conclude that the GHR-TACE interaction precedes proteolysis, and is transient. Furthermore, we demonstrate that TACE is present in endosomes, where it partly co-localizes with endocytosed growth hormone ligand.
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Affiliation(s)
- Julia A Schantl
- Department of Cell Biology, University Medical Center Utrecht, The Netherlands
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25
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Yang ZZ, Tschopp O, Hemmings-Mieszczak M, Feng J, Brodbeck D, Perentes E, Hemmings BA. Protein kinase B alpha/Akt1 regulates placental development and fetal growth. J Biol Chem 2003; 278:32124-31. [PMID: 12783884 DOI: 10.1074/jbc.m302847200] [Citation(s) in RCA: 292] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein kinase B alpha (PKB alpha/Akt1) is implicated in the regulation of metabolism, transcription, cell survival, angiogenesis, cell migration, growth, and tumorigenesis. Previously, it was reported that PKB alpha-deficient mice are small with increased neonatal mortality (Cho, H., Thorvaldsen, J. L., Chu, Q., Feng, F., and Birnbaum, M. J. (2001) J. Biol. Chem. 276, 38349-38352 and Chen, W. S., Xu, P. Z., Gottlob, K., Chen, M. L., Sokol, K., Shiyanova, T., Roninson, I., Wenig, W., Suzuki, R., Tobe, K., Kadowaki, T., and Hay, N. (2001) Genes Dev. 15, 2203-2208). Here we show that PKB alpha is widely expressed in placenta including all types of trophoblast and vascular endothelial cells. Pkb alpha-/- placentae display significant hypotrophy, with marked reduction of the decidual basalis and nearly complete loss of glycogen-containing cells in the spongiotrophoblast, and exhibit decreased vascularization. Pkb alpha-/- placentae also show significant reduction of phosphorylation of PKB and endothelial nitric-oxide synthase. These defects may cause placental insufficiency, fetal growth impairment, and neonatal mortality. These data represent the first evidence for the role of PKB alpha and endothelial nitricoxide synthase in regulating placental development and provide an animal model for intrauterine growth retardation.
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Affiliation(s)
- Zhong-Zhou Yang
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
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26
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Zhang X, Zhu T, Chen Y, Mertani HC, Lee KO, Lobie PE. Human growth hormone-regulated HOXA1 is a human mammary epithelial oncogene. J Biol Chem 2003; 278:7580-90. [PMID: 12482855 DOI: 10.1074/jbc.m212050200] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Increased mammary epithelial expression of the human growth hormone (hGH) gene is associated with the acquisition of pathological proliferation. We report here that autocrine hGH production by human mammary carcinoma cells increased the expression and transcriptional activity of the homeobox domain containing protein HOXA1. Forced expression of HOXA1 in human mammary carcinoma cells resulted in increased total cell number primarily by the promotion of cell survival mediated by the transcriptional up-regulation of Bcl-2. HOXA1 also abrogated the apoptotic response of mammary carcinoma cells to doxorubicin. Forced expression of HOXA1 in mammary carcinoma cells, in a Bcl-2-dependent manner, resulted in dramatic enhancement of anchorage-independent proliferation and colony formation in soft agar. Finally, forced expression of HOXA1 was sufficient to result in the oncogenic transformation of immortalized human mammary epithelial cells with aggressive in vivo tumor formation. Herein, we have therefore provided a molecular mechanism by which autocrine hGH stimulation of human mammary epithelial cells may result in oncogenic transformation.
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MESH Headings
- Animals
- Antimetabolites/pharmacology
- Antineoplastic Agents/pharmacology
- Apoptosis
- Blotting, Western
- Breast/metabolism
- Bromodeoxyuridine/pharmacology
- Cell Cycle
- Cell Transformation, Neoplastic
- Cells, Cultured
- DNA, Complementary/metabolism
- Doxorubicin/pharmacology
- Epithelial Cells/metabolism
- Epithelium/metabolism
- Genes, Reporter
- Homeodomain Proteins/metabolism
- Homeodomain Proteins/physiology
- Human Growth Hormone/metabolism
- Humans
- Luciferases/metabolism
- Mice
- Mice, SCID
- Neoplasm Transplantation
- Oligonucleotide Array Sequence Analysis
- Oligonucleotides, Antisense/pharmacology
- Promoter Regions, Genetic
- Proto-Oncogene Proteins c-bcl-2/metabolism
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Time Factors
- Transcription Factors/metabolism
- Transcription Factors/physiology
- Transcription, Genetic
- Transfection
- Tumor Cells, Cultured
- Up-Regulation
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Affiliation(s)
- Xin Zhang
- Institute of Molecular and Cell Biology and Department of Medicine, National University of Singapore, 30 Medical Dr., Singapore 117609, Republic of Singapore
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27
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De Meyts P, Whittaker J. Structural biology of insulin and IGF1 receptors: implications for drug design. Nat Rev Drug Discov 2002; 1:769-83. [PMID: 12360255 DOI: 10.1038/nrd917] [Citation(s) in RCA: 434] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Type 2 diabetes mellitus -- in which the body produces insufficient amounts of insulin or the insulin that is produced does not function properly to control blood glucose -- is an increasingly common disorder. Prospective clinical studies have proven the benefits of tighter glucose control in reducing the frequency and severity of complications of the disease, leading to the advocation of earlier and more aggressive use of insulin therapy. Given the reluctance of patients with type 2 diabetes to inject themselves with insulin, orally active insulin mimetics would be a major therapeutic advance. Here, we discuss recent progress in understanding the structure-function relationships of the insulin and insulin-like growth factor 1 (IGF1) receptors, their mechanism of activation and their implications for the design of insulin-receptor agonists for diabetes therapy and IGF1-receptor antagonists for cancer therapy.
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Affiliation(s)
- Pierre De Meyts
- Receptor Biology Laboratory, Hagedorn Research Institute, Niels Steensens Vej 6, DK-2820 Gentofte, Denmark.
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