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Prochownik EV, Wang H. Normal and Neoplastic Growth Suppression by the Extended Myc Network. Cells 2022; 11:747. [PMID: 35203395 PMCID: PMC8870482 DOI: 10.3390/cells11040747] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/09/2022] [Accepted: 02/15/2022] [Indexed: 12/20/2022] Open
Abstract
Among the first discovered and most prominent cellular oncogenes is MYC, which encodes a bHLH-ZIP transcription factor (Myc) that both activates and suppresses numerous genes involved in proliferation, energy production, metabolism and translation. Myc belongs to a small group of bHLH-ZIP transcriptional regulators (the Myc Network) that includes its obligate heterodimerization partner Max and six "Mxd proteins" (Mxd1-4, Mnt and Mga), each of which heterodimerizes with Max and largely opposes Myc's functions. More recently, a second group of bHLH-ZIP proteins (the Mlx Network) has emerged that bears many parallels with the Myc Network. It is comprised of the Myc-like factors ChREBP and MondoA, which, in association with the Max-like member Mlx, regulate smaller and more functionally restricted repertoires of target genes, some of which are shared with Myc. Opposing ChREBP and MondoA are heterodimers comprised of Mlx and Mxd1, Mxd4 and Mnt, which also structurally and operationally link the two Networks. We discuss here the functions of these "Extended Myc Network" members, with particular emphasis on their roles in suppressing normal and neoplastic growth. These roles are complex due to the temporal- and tissue-restricted expression of Extended Myc Network proteins in normal cells, their regulation of both common and unique target genes and, in some cases, their functional redundancy.
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Affiliation(s)
- Edward V. Prochownik
- Division of Hematology/Oncology, The Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA;
- The Department of Microbiology and Molecular Genetics, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
- The Hillman Cancer Center of UPMC, Pittsburgh, PA 15224, USA
- The Pittsburgh Liver Research Center, Pittsburgh, PA 15224, USA
| | - Huabo Wang
- Division of Hematology/Oncology, The Department of Pediatrics, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA;
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McQuilling JP, Burnette M, Kimmerling KA, Kammer M, Mowry KC. A mechanistic evaluation of the angiogenic properties of a dehydrated amnion chorion membrane in vitro and in vivo. Wound Repair Regen 2019; 27:609-621. [PMID: 31425636 PMCID: PMC6900065 DOI: 10.1111/wrr.12757] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/10/2019] [Indexed: 12/20/2022]
Abstract
Angiogenesis is essential for the successful repair of tissues; however, in many chronic conditions, angiogenesis is inhibited. Placental tissues have been shown to illicit an angiogenic response both in vitro and in vivo, and the angiogenic properties of these tissues likely contribute to observed clinical outcomes. Although there is some work describing the angiogenic effects of these tissues, comparatively little has been done to determine the possible mechanisms responsible for this effect. The purpose of this study was to conduct a thorough evaluation of a commercially available dehydrated amnion chorion membrane to better understand how these tissues may promote angiogenesis. The proteomic content of this tissue was evaluated using a high throughput proteomic microarray, and then the effects of these grafts were evaluated in vivo using subcutaneous gelfoam sponge implants containing conditioned media (CM) from the graft. Human microvascular endothelial cells were then used to determine how released factors effect migration, proliferation, gene expression, and protein production in vitro. Finally, to elucidate potential signaling‐pathways through which tissue‐derived factors act to induce pro‐angiogenetic phenotypes in endothelial cells in vitro, we performed a global analysis of both serine/threonine and tyrosine kinase activity. Kinomic and proteomic data were then combined to generate protein–protein interaction networks that enabled the identification of multiple growth factors and cytokines with both pro‐ and anti‐angiogenetic properties. In vivo, the addition of CM resulted in increased CD31 and αSMA staining and increases in pro‐angiogenic gene expression. In vitro, CM resulted in significant increases in endothelial proliferation, migration, and the expression of granulocyte‐macrophage colony‐stimulating factor, hepatocyte growth factor, and transforming growth factor beta‐3. Integrated kinomic analysis implicated ERK1/2 signaling as the primary pathway activated following culture of endothelial cells with dehydrated amnion/chorion membrane (dACM) CM. In conclusion, dACM grafts triggered pro‐angiogenic responses both in vitro and in vivo that are likely at least partially mediated by ERK1/2 signaling.
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Affiliation(s)
- John P McQuilling
- Research and Development, Organogenesis, 2641 Rock Ridge Lane Birmingham, Alabama, 35216
| | - Miranda Burnette
- Research and Development, Organogenesis, 2641 Rock Ridge Lane Birmingham, Alabama, 35216
| | - Kelly A Kimmerling
- Research and Development, Organogenesis, 2641 Rock Ridge Lane Birmingham, Alabama, 35216
| | - MaryRose Kammer
- Research and Development, Organogenesis, 2641 Rock Ridge Lane Birmingham, Alabama, 35216
| | - Katie C Mowry
- Research and Development, Organogenesis, 2641 Rock Ridge Lane Birmingham, Alabama, 35216
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3
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Coating extracellular matrix proteins on a (3-aminopropyl)triethoxysilane-treated glass substrate for improved cell culture. Biotechniques 2014; 56:172-9. [PMID: 24724842 DOI: 10.2144/000114156] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 01/29/2014] [Indexed: 11/23/2022] Open
Abstract
We demonstrate that a (3-aminopropyl)triethoxysilane-treated glass surface is superior to an untreated glass surface for coating with extracellular matrix (ECM) proteins when used as a cell culture substrate to observe cell physiology and behavior. We found that MDCK cells cultured on untreated glass coated with ECM removed the coated ECM protein and secreted different ECM proteins. In contrast, the cells did not remove the coated ECM protein when seeded on (3-aminopropyl)triethoxysilane-treated (i.e., silanized) glass coated with ECM. Furthermore, the morphology and motility of cells grown on silanized glass differed from those grown on non-treated glass, even when both types of glass were initially coated with laminin. We also found that cells on silanized glass coated with laminin had higher motility than those on silanized glass coated with fibronectin. Based on our results, we suggest that silanized glass is a more suitable cell culture substrate than conventional non-treated glass when coated by ECM for observations of ECM effects on cell physiology.
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Activation of ERK accelerates repair of renal tubular epithelial cells, whereas it inhibits progression of fibrosis following ischemia/reperfusion injury. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1998-2008. [DOI: 10.1016/j.bbadis.2013.07.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 06/12/2013] [Accepted: 07/01/2013] [Indexed: 11/18/2022]
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Wells EK, Yarborough O, Lifton RP, Cantley LG, Caplan MJ. Epithelial morphogenesis of MDCK cells in three-dimensional collagen culture is modulated by interleukin-8. Am J Physiol Cell Physiol 2013; 304:C966-75. [PMID: 23485708 DOI: 10.1152/ajpcell.00261.2012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Epithelial morphogenesis is dependent upon a variety of factors, many of which involve complex interactions between cells and their surrounding environments. We analyzed the patterns of differential gene expression associated with Madin-Darby canine kidney (MDCK) renal epithelial cells grown within a collagen gel in three-dimensional (3D) culture compared with those grown atop a collagen gel in two-dimensional (2D) culture. Under these conditions, MDCK cells spontaneously formed either hollow spherical cysts or flat monolayer sheets, respectively. Microarray analysis of gene expression revealed a twofold or greater expression difference in 732 gene sets from MDCK cysts compared with monolayers (false discovery rate or FDR-adjusted P values <0.05). Interleukin-8 (IL-8) was reproducibly found to be among the genes whose expression was most dramatically upregulated, and this behavior was verified through real-time PCR analysis. The level of IL-8 protein expression was significantly increased in 3D MDCK cultures compared with that detected in cells in 2D culture. Hepatocyte growth factor (HGF) induces MDCK cells in 3D culture to form linear tubule-like structures. We found that HGF stimulation caused MDCK cells in 3D culture to decrease the expression of IL-8 at both the mRNA and protein levels. Furthermore, the addition of recombinant IL-8 to HGF-stimulated 3D MDCK cultures was sufficient to partially reverse the tubulogenic effects of HGF, resulting in the formation of cystic structures. These data suggest that IL-8 participates in the formation of cystic structures by MDCK cells in 3D culture and that HGF may stimulate tubulogenesis through the suppression of IL-8.
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Affiliation(s)
- Erika K Wells
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
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Abstract
Cell polarity is fundamental for the architecture and function of epithelial tissues. Epithelial polarization requires the intervention of several fundamental cell processes, whose integration in space and time is only starting to be elucidated. To understand what governs the building of epithelial tissues during development, it is essential to consider the polarization process in the context of the whole tissue. To this end, the development of three-dimensional organotypic cell culture models has brought new insights into the mechanisms underlying the establishment and maintenance of higher-order epithelial tissue architecture, and in the dynamic remodeling of cell polarity that often occurs during development of epithelial organs. Here we discuss some important aspects of mammalian epithelial morphogenesis, from the establishment of cell polarity to epithelial tissue generation.
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Song SA, Yoo KH, Ko JY, Kim BH, Yook YJ, Park JH. Over-expression of Mxi1 represses renal epithelial tubulogenesis through the reduction of matrix metalloproteinase 9. Biochem Biophys Res Commun 2012; 419:459-65. [DOI: 10.1016/j.bbrc.2012.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 02/01/2012] [Indexed: 10/14/2022]
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Buchholz B, Klanke B, Schley G, Bollag G, Tsai J, Kroening S, Yoshihara D, Wallace DP, Kraenzlin B, Gretz N, Hirth P, Eckardt KU, Bernhardt WM. The Raf kinase inhibitor PLX5568 slows cyst proliferation in rat polycystic kidney disease but promotes renal and hepatic fibrosis. Nephrol Dial Transplant 2011; 26:3458-65. [PMID: 21804086 DOI: 10.1093/ndt/gfr432] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is a common cause of renal failure. Aberrant epithelial cell proliferation is a major cause of progressive cyst enlargement in ADPKD. Since activation of the Ras/Raf signaling system has been detected in cyst-lining epithelia, inhibition of Raf kinase has been proposed as an approach to retard the progression of ADPKD. Methods and results. PLX5568, a novel selective small molecule inhibitor of Raf kinases, attenuated proliferation of human ADPKD cyst epithelial cells. It reduced in vitro cyst growth of Madin-Darby Canine Kidney cells and of human ADPKD cells within a collagen gel. In male cy/+ rats with polycystic kidneys, PLX5568 inhibited renal cyst growth along with a significant reduction in the number of proliferating cell nuclear antigen- and phosphorylated extracellular signal-regulated kinase-positive cyst-lining epithelial cells. Furthermore, treated animals showed increased capacity to concentrate urine. However, PLX5568 did not lead to a consistent improvement of renal function. Moreover, although relative cyst volume was decreased, total kidney-to-body weight ratio was not significantly reduced by PLX5568. Further analyses revealed a 2-fold increase of renal and hepatic fibrosis in animals treated with PLX5568. CONCLUSIONS PLX5568 attenuated cyst enlargement in vitro and in a rat model of ADPKD without improving kidney function, presumably due to increased renal fibrosis. These data suggest that effective therapies for the treatment of ADPKD will need to target fibrosis as well as the growth of cysts.
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Affiliation(s)
- Bjoern Buchholz
- Department of Nephrology and Hypertension, University of Erlangen-Nürnberg, Erlangen, Germany.
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Guizzetti M, Moore NH, VanDeMark KL, Giordano G, Costa LG. Muscarinic receptor-activated signal transduction pathways involved in the neuritogenic effect of astrocytes in hippocampal neurons. Eur J Pharmacol 2011; 659:102-7. [PMID: 21453700 DOI: 10.1016/j.ejphar.2011.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Revised: 02/22/2011] [Accepted: 03/14/2011] [Indexed: 11/25/2022]
Abstract
Astrocytes have been shown to release factors that affect various aspects of neuronal development. We have previously shown that the acetylcholine analog carbachol, by activating muscarinic M(3) receptors in rat astrocytes, increases their ability to promote neuritogenesis in hippocampal neurons. This effect was mediated by an increased expression and release by astrocytes of several permissive factors, a most relevant of which was fibronectin. In the present study we investigated the signal transduction pathways involved in these effects of carbachol in astrocytes. Results show that multiple pathways are involved in the effects of carbachol on astrocyte-mediated increases in fibronectin expression and neuritogenesis. These include the phospholipase D pathway, leading to sequential activation of protein kinase C (PKC) ζ, p70S6 kinase and nuclear factor-κB; the phosphoinositide-3 kinase pathway; and the PKC ε pathway leading to activation of mitogen activated protein kinase. These pathways were shown to mediate the effect of carbachol on neurite outgrowth as well as the increased expression of fibronectin, further substantiating the important role of the latter in astrocyte-mediated neuritogenesis. Interference with these signaling pathways would be expected to impair astrocyte-neurons communication leading to impaired neuronal development.
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Affiliation(s)
- Marina Guizzetti
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98105, USA
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Park KM, Fogelgren B, Zuo X, Kim J, Chung DC, Lipschutz JH. Exocyst Sec10 protects epithelial barrier integrity and enhances recovery following oxidative stress, by activation of the MAPK pathway. Am J Physiol Renal Physiol 2010; 298:F818-26. [PMID: 20053792 DOI: 10.1152/ajprenal.00596.2009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cell-cell contacts are essential for epithelial cell function, and disruption is associated with pathological conditions including ischemic kidney injury. We hypothesize that the exocyst, a highly-conserved eight-protein complex that targets secretory vesicles carrying membrane proteins, is involved in maintaining renal epithelial barrier integrity. Accordingly, increasing exocyst expression in renal tubule cells may protect barrier function from oxidative stress resulting from ischemia and reperfusion (I/R) injury. When cultured on plastic, Madin-Darby canine kidney (MDCK) cells overexpressing Sec10, a central exocyst component, formed domes showing increased resistance to hydrogen peroxide (H2O2). Transepithelial electric resistance (TER) of Sec10-overexpressing MDCK cells grown on Transwell filters was higher than in control MDCK cells, and the rate of TER decrease following H2O2 treatment was less in Sec10-overexpressing MDCK cells compared with control MDCK cells. After removal of H2O2, TER returned to normal more rapidly in Sec10-overexpressing compared with control MDCK cells. In collagen culture MDCK cells form cysts, and H2O2 treatment damaged Sec10-overexpressing MDCK cell cysts less than control MDCK cell cysts. The MAPK pathway has been shown to protect animals from I/R injury. Levels of active ERK, the final MAPK pathway step, were higher in Sec10-overexpressing compared with control MDCK cells. U0126 inhibited ERK activation, exacerbated the H2O2-induced decrease in TER and cyst disruption, and delayed recovery of TER following H2O2 removal. Finally, in mice with renal I/R injury, exocyst expression decreased early and returned to normal concomitant with functional recovery, suggesting that the exocyst may be involved in the recovery following I/R injury.
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Affiliation(s)
- Kwon Moo Park
- Department of Medicine, University of Pennsylvania, and the Veterans Administration Medical Center, Philadelphia, Pennsylvania, USA
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Cantaluppi V, Biancone L, Romanazzi GM, Figliolini F, Beltramo S, Galimi F, Camboni MG, Deriu E, Conaldi P, Bottelli A, Orlandi V, Herrera MB, Pacitti A, Segoloni GP, Camussi G. Macrophage stimulating protein may promote tubular regeneration after acute injury. J Am Soc Nephrol 2008; 19:1904-18. [PMID: 18614774 DOI: 10.1681/asn.2007111209] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Macrophage-stimulating protein (MSP) exerts proliferative and antiapoptotic effects, suggesting that it may play a role in tubular regeneration after acute kidney injury. In this study, elevated plasma levels of MSP were found both in critically ill patients with acute renal failure and in recipients of renal allografts during the first week after transplantation. In addition, MSP and its receptor, RON, were markedly upregulated in the regenerative phase after glycerol-induced tubular injury in mice. In vitro, MSP stimulated tubular epithelial cell proliferation and conferred resistance to cisplatin-induced apoptosis by inhibiting caspase activation and modulating Fas, mitochondrial proteins, Akt, and extracellular signal-regulated kinase. MSP also enhanced migration, scattering, branching morphogenesis, tubulogenesis, and mesenchymal de-differentiation of surviving tubular cells. In addition, MSP induced an embryonic phenotype characterized by Pax-2 expression. In conclusion, MSP is upregulated during the regeneration of injured tubular cells, and it exerts multiple biologic effects that may aid recovery from acute kidney injury.
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Affiliation(s)
- Vincenzo Cantaluppi
- Research Center for Experimental Medicine, Department of Internal Medicine, University of Torino, Torino, Italy
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Petersen MC, Lazar J, Jacob HJ, Wakatsuki T. Tissue engineering: a new frontier in physiological genomics. Physiol Genomics 2007; 32:28-32. [DOI: 10.1152/physiolgenomics.00165.2007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Considerable progress has been made in the last decade in the engineering and construction of a number of artificial tissue types. These constructs are typically viewed from the perspective of possible sources for implant and transplant materials in the clinical arena. However, incorporation of engineered tissues, often referred to as three-dimensional (3D) cell culture, also offers the possibility for significant advancements in research for physiological genomics. These 3D systems more readily mimic the in vivo setting than traditional 2D cell culture, and offer distinct advantages over the in vivo setting for some organ systems. As an example, cardiac cells in 3D culture 1) are more accessible for siRNA studies, 2) can be engineered with specific cell types, and 3) offer the potential for high-throughput screening of gene function. Here the state-of-the-art is reviewed and the applications for engineered tissue in genomics research are proposed. The ability to use engineered tissue in combination with genomics creates a bridge between traditional cellular and in vivo studies that is critical to enabling the transition of genetic information into mechanistic understanding of disease processes.
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Affiliation(s)
- Matthew C. Petersen
- Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Biotechnology & Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Jozef Lazar
- Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Dermatology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Human Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Howard J. Jacob
- Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Human Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin
- Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Tetsuro Wakatsuki
- Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Biotechnology & Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin
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Hellman NE, Spector J, Robinson J, Zuo X, Saunier S, Antignac C, Tobias JW, Lipschutz JH. Matrix metalloproteinase 13 (MMP13) and tissue inhibitor of matrix metalloproteinase 1 (TIMP1), regulated by the MAPK pathway, are both necessary for Madin-Darby canine kidney tubulogenesis. J Biol Chem 2007; 283:4272-82. [PMID: 18039671 DOI: 10.1074/jbc.m708027200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A classic model of tubulogenesis utilizes Madin-Darby canine kidney (MDCK) cells. MDCK cells form monoclonal cysts in three-dimensional collagen and tubulate in response to hepatocyte growth factor, which activates multiple signaling pathways, including the mitogen-activated protein kinase (MAPK) pathway. It was shown previously that MAPK activation is necessary and sufficient to induce the first stage of tubulogenesis, the partial epithelial to mesenchymal transition (p-EMT), whereas matrix metalloproteinases (MMPs) are necessary for the second redifferentiation stage. To identify specific MMP genes, their regulators, tissue inhibitors of matrix metalloproteinases (TIMPs), and the molecular pathways by which they are activated, we used two distinct MAPK inhibitors and a technique we have termed subtraction pathway microarray analysis. Of the 19 MMPs and 3 TIMPs present on the Canine Genome 2.0 Array, MMP13 and TIMP1 were up-regulated 198- and 169-fold, respectively, via the MAPK pathway. This was confirmed by two-dimensional and three-dimensional real time PCR, as well as in MDCK cells inducible for the MAPK gene Raf. Knockdown of MMP13 using short hairpin RNA prevented progression past the initial phase of p-EMT. Knockdown of TIMP1 prevented normal cystogenesis, although the initial phase of p-EMT did occasionally occur. The MMP13 knockdown phenotype is likely because of decreased collagenase activity, whereas the TIMP1 knockdown phenotype appears due to increased apoptosis. These data suggest a model, which may also be important for development of other branched organs, whereby the MAPK pathway controls both MDCK p-EMT and redifferentiation, in part by activating MMP13 and TIMP1.
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Affiliation(s)
- Nathan E Hellman
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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