201
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Abstract
Fibroblasts migrate on two-dimensional (2D) surfaces by forming lamellipodia-actin-rich extensions at the leading edge of the cell that have been well characterized. In this issue, Petrie et al. (2012. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201201124) show that in some 3D environments, including tissue explants, fibroblasts project different structures, termed lobopodia, at the leading edge. Lobopodia still assemble focal adhesions; however, similar to membrane blebs, they are driven by actomyosin contraction and do not accumulate active Rac, Cdc42, and phosphatidylinositol 3-kinases.
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Affiliation(s)
- Michael Sixt
- Institute of Science and Technology Austria, Klosterneuburg, Austria.
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202
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Jayo A, Parsons M. Imaging of cell adhesion events in 3D matrix environments. Eur J Cell Biol 2012; 91:824-33. [PMID: 22705211 DOI: 10.1016/j.ejcb.2012.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 05/08/2012] [Accepted: 05/08/2012] [Indexed: 01/28/2023] Open
Abstract
Cell adhesion plays an essential role in development and homeostasis, but is also a key regulator of many diseases such as cancer and immune dysfunction. Numerous studies over the past three decades have revealed a wealth of information detailing signalling molecules required for cell adhesion to two-dimensional surfaces. However, in vivo many cells are completely surrounded by matrix and this will very likely influence the size, composition and dynamics of adhesive structures. The study of adhesion in cells within three-dimensional environments is still in its infancy, thus the role and regulation of adhesions in these complex environments remains unclear. The recent development of new experimental models coupled with significant advances in cell imaging approaches have provided platforms for researchers to begin to dissect adhesion signalling in cells in 3D matrices. Here we summarise the recent insights in cell adhesion formation and regulation in 3D model systems and the imaging approaches used to analyse these events.
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Affiliation(s)
- Asier Jayo
- Randall Division of Cell and Molecular Biophysics, King's College London, Guys Campus, UK
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203
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Balzer EM, Tong Z, Paul CD, Hung WC, Stroka KM, Boggs AE, Martin SS, Konstantopoulos K. Physical confinement alters tumor cell adhesion and migration phenotypes. FASEB J 2012; 26:4045-56. [PMID: 22707566 DOI: 10.1096/fj.12-211441] [Citation(s) in RCA: 199] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Cell migration on planar surfaces is driven by cycles of actin protrusion, integrin-mediated adhesion, and myosin-mediated contraction; however, this mechanism may not accurately describe movement in 3-dimensional (3D) space. By subjecting cells to restrictive 3D environments, we demonstrate that physical confinement constitutes a biophysical stimulus that alters cell morphology and suppresses mesenchymal motility in human breast carcinoma (MDA-MB-231). Dorsoventral polarity, stress fibers, and focal adhesions are markedly attenuated by confinement. Inhibitors of myosin, Rho/ROCK, or β1-integrins do not impair migration through 3-μm-wide channels (confinement), even though these treatments repress motility in 50-μm-wide channels (unconfined migration) by ≥50%. Strikingly, confined migration persists even when F-actin is disrupted, but depends largely on microtubule (MT) dynamics. Interfering with MT polymerization/depolymerization causes confined cells to undergo frequent directional changes, thereby reducing the average net displacement by ≥80% relative to vehicle controls. Live-cell EB1-GFP imaging reveals that confinement redirects MT polymerization toward the leading edge, where MTs continuously impact during advancement of the cell front. These results demonstrate that physical confinement can induce cytoskeletal alterations that reduce the dependence of migrating cells on adhesion-contraction force coupling. This mechanism may explain why integrins can exhibit reduced or altered function during migration in 3D environments.
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Affiliation(s)
- Eric M Balzer
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins Physical Sciences-Oncology Center, Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
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204
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Branch KM, Hoshino D, Weaver AM. Adhesion rings surround invadopodia and promote maturation. Biol Open 2012; 1:711-22. [PMID: 23213464 PMCID: PMC3507228 DOI: 10.1242/bio.20121867] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 05/21/2012] [Indexed: 12/19/2022] Open
Abstract
Invasion and metastasis are aggressive cancer phenotypes that are highly related to the ability of cancer cells to degrade extracellular matrix (ECM). At the cellular level, specialized actin-rich structures called invadopodia mediate focal matrix degradation by serving as exocytic sites for ECM-degrading proteinases. Adhesion signaling is likely to be a critical regulatory input to invadopodia, but the mechanism and location of such adhesion signaling events are poorly understood. Here, we report that adhesion rings surround invadopodia shortly after formation and correlate strongly with invadopodium activity on a cell-by-cell basis. By contrast, there was little correlation of focal adhesion number or size with cellular invadopodium activity. Prevention of adhesion ring formation by inhibition of RGD-binding integrins or knockdown (KD) of integrin-linked kinase (ILK) reduced the number of ECM-degrading invadopodia and reduced recruitment of IQGAP to invadopodium actin puncta. Furthermore, live cell imaging revealed that the rate of extracellular MT1-MMP accumulation at invadopodia was greatly reduced in both integrin-inhibited and ILK-KD cells. Conversely, KD of MT1-MMP reduced invadopodium activity and dynamics but not the number of adhesion-ringed invadopodia. These results suggest a model in which adhesion rings are recruited to invadopodia shortly after formation and promote invadopodium maturation by enhancing proteinase secretion. Since adhesion rings are a defining characteristic of podosomes, similar structures formed by normal cells, our data also suggest further similarities between invadopodia and podosomes.
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Affiliation(s)
- Kevin M Branch
- Department of Cancer Biology, Vanderbilt University School of Medicine , Nashville, TN 37232 , USA
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205
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DeLay M, Jahangiri A, Carbonell WS, Hu YL, Tsao S, Tom MW, Paquette J, Tokuyasu TA, Aghi MK. Microarray analysis verifies two distinct phenotypes of glioblastomas resistant to antiangiogenic therapy. Clin Cancer Res 2012; 18:2930-42. [PMID: 22472177 DOI: 10.1158/1078-0432.ccr-11-2390] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To identify mechanisms and mediators of resistance to antiangiogenic therapy in human glioblastoma. EXPERIMENTAL DESIGN We carried out microarray gene expression analysis and immunohistochemistry comparing 21 recurrent glioblastomas progressing during antiangiogenic treatment with VEGF neutralizing antibody bevacizumab to paired pretreatment tumors from the same patients. RESULTS Microarray analysis revealed that bevacizumab-resistant glioblastomas (BRG) had two clustering patterns defining subtypes that reflect radiographic growth patterns. Enhancing BRGs (EBRG) exhibited MRI enhancement, a long-established criterion for glioblastoma progression, and expressed mitogen-activated protein kinases, neural cell adhesion molecule-1 (NCAM-1), and aquaporin 4. Compared with their paired pretreatment tumors, EBRGs had unchanged vascularity and hypoxia, with increased proliferation. Nonenhancing BRGs (NBRG) exhibited minimal MRI enhancement but had FLAIR-bright expansion, a newer criterion for glioblastoma recurrence since the advent of antiangiogenic therapy, and expressed integrin α5, laminin, fibronectin1, and PDGFRβ. NBRGs had less vascularity, more hypoxia, and unchanged proliferation than their paired pretreatment tumors. Primary NBRG cells exhibited more stellate morphology with a 3-fold increased shape factor and were nearly 4-fold more invasive in Matrigel chambers than primary cells from EBRGs or bevacizumab-naive glioblastomas (P < 0.05). CONCLUSION Using microarray analysis, we found two resistance patterns during antiangiogenic therapy with distinct molecular profiles and radiographic growth patterns. These studies provide valuable biologic insight into the resistance that has limited antiangiogenic therapy to date.
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Affiliation(s)
- Michael DeLay
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California 94143, USA
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206
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Kraning-Rush CM, Carey SP, Califano JP, Reinhart-King CA. Quantifying Traction Stresses in Adherent Cells. Methods Cell Biol 2012; 110:139-78. [DOI: 10.1016/b978-0-12-388403-9.00006-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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207
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Gu W, Katz Z, Wu B, Park HY, Li D, Lin S, Wells AL, Singer RH. Regulation of local expression of cell adhesion and motility-related mRNAs in breast cancer cells by IMP1/ZBP1. J Cell Sci 2012; 125:81-91. [PMID: 22266909 PMCID: PMC3269024 DOI: 10.1242/jcs.086132] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2011] [Indexed: 02/05/2023] Open
Abstract
Metastasis involves tumor cell detachment from the primary tumor, and acquisition of migratory and invasive capabilities. These capabilities are mediated by multiple events, including loss of cell-cell contact, an increase in focal adhesion turnover and failure to maintain a normal cell polarity. We have previously reported that silencing of the expression of the zipcode-binding protein IMP1/ZBP1 in breast tumor patients is associated with metastasis. IMP1/ZBP1 selectively binds to a group of mRNAs that encode important mediators for cell adhesion and motility. Here, we show that in both T47D and MDA231 human breast carcinoma cells IMP1/ZBP1 functions to suppress cell invasion. Binding of ZBP1 to the mRNAs encoding E-cadherin, β-actin, α-actinin and the Arp2/3 complex facilitates localization of the mRNAs, which stabilizes cell-cell connections and focal adhesions. Our studies suggest a novel mechanism through which IMP1/ZBP1 simultaneously regulates the local expression of many cell-motility-related mRNAs to maintain cell adherence and polarity, decrease focal adhesion turnover and maintain a persistent and directional motility.
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Affiliation(s)
- Wei Gu
- Department of Pathophysiology, The Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province, 515031, China
- Authors for correspondence (; )
| | - Zachary Katz
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx NY 10461, USA
| | - Bin Wu
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx NY 10461, USA
| | - Hye Yoon Park
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx NY 10461, USA
| | - Deling Li
- Department of Pathophysiology, The Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province, 515031, China
| | - Stanley Lin
- Department of Pathophysiology, The Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province, 515031, China
| | - Amber L. Wells
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx NY 10461, USA
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY 10461, USA
| | - Robert H. Singer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx NY 10461, USA
- Authors for correspondence (; )
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208
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Alexander S, Friedl P. Cancer invasion and resistance: interconnected processes of disease progression and therapy failure. Trends Mol Med 2012; 18:13-26. [DOI: 10.1016/j.molmed.2011.11.003] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 10/07/2011] [Accepted: 11/08/2011] [Indexed: 12/27/2022]
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209
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Hawkins RJ, Poincloux R, Bénichou O, Piel M, Chavrier P, Voituriez R. Spontaneous contractility-mediated cortical flow generates cell migration in three-dimensional environments. Biophys J 2011; 101:1041-5. [PMID: 21889440 DOI: 10.1016/j.bpj.2011.07.038] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 07/25/2011] [Accepted: 07/26/2011] [Indexed: 01/17/2023] Open
Abstract
We present a model of cell motility generated by actomyosin contraction of the cell cortex. We identify, analytically, dynamical instabilities of the cortex and show that they yield steady-state cortical flows, which, in turn, can induce cell migration in three-dimensional environments. This mechanism relies on the regulation of contractility by myosin, whose transport is explicitly taken into account in the model. Theoretical predictions are compared to experimental data of tumor cells migrating in three-dimensional matrigel and suggest that this mechanism could be a general mode of cell migration in three-dimensional environments.
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Affiliation(s)
- Rhoda J Hawkins
- UMR 7600, Université Pierre et Marie Curie/CNRS (Centre National de la Recherche Scientifique), Paris, France.
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210
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Carey SP, D'Alfonso TM, Shin SJ, Reinhart-King CA. Mechanobiology of tumor invasion: engineering meets oncology. Crit Rev Oncol Hematol 2011; 83:170-83. [PMID: 22178415 DOI: 10.1016/j.critrevonc.2011.11.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 11/14/2011] [Accepted: 11/16/2011] [Indexed: 12/21/2022] Open
Abstract
The physical sciences and engineering have introduced novel perspectives into the study of cancer through model systems, tools, and metrics that enable integration of basic science observations with clinical data. These methods have contributed to the identification of several overarching mechanisms that drive processes during cancer progression including tumor growth, angiogenesis, and metastasis. During tumor cell invasion - the first clinically observable step of metastasis - cells demonstrate diverse and evolving physical phenotypes that cannot typically be defined by any single molecular mechanism, and mechanobiology has been used to study the physical cell behaviors that comprise the "invasive phenotype". In this review, we discuss the continually evolving pathological characterization and in vitro mechanobiological characterization of tumor invasion, with emphasis on emerging physical biology and mechanobiology strategies that have contributed to a more robust mechanistic understanding of tumor cell invasion. These physical approaches may ultimately help to better predict and identify tumor metastasis.
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Affiliation(s)
- Shawn P Carey
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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211
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Botta GP, Reginato MJ, Reichert M, Rustgi AK, Lelkes PI. Constitutive K-RasG12D activation of ERK2 specifically regulates 3D invasion of human pancreatic cancer cells via MMP-1. Mol Cancer Res 2011; 10:183-96. [PMID: 22160930 DOI: 10.1158/1541-7786.mcr-11-0399] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Pancreatic ductal adenocarcinomas (PDAC) are highly invasive and metastatic neoplasms commonly unresponsive to current drug therapy. Overwhelmingly, PDAC harbors early constitutive, oncogenic mutations in K-Ras(G12D) that exist prior to invasion. Histologic and genetic analyses of human PDAC biopsies also exhibit increased expression of extracellular signal-regulated kinase (ERK) 1/2 and proinvasive matrix metalloproteinases (MMP), indicators of poor prognosis. However, the distinct molecular mechanisms necessary for K-Ras/ERK1/2 signaling and its influence on MMP-directed stromal invasion in primary human pancreatic ductal epithelial cells (PDEC) have yet to be elucidated in three-dimensions. Expression of oncogenic K-Ras(G12D) alone in genetically defined PDECs reveals increased invadopodia and epithelial-to-mesenchymal transition markers, but only when cultured in a three-dimensional model incorporating a basement membrane analog. Activation of ERK2, but not ERK1, also occurs only in K-Ras(G12D)-mutated PDECs cultured in three-dimensions and is a necessary intracellular signaling event for invasion based upon pharmacologic and short hairpin RNA (shRNA) inhibition. Increased active invasion of K-Ras(G12D) PDECs through the basement membrane model is associated with a specific microarray gene expression signature and induction of MMP endopeptidases. Specifically, MMP-1 RNA, its secreted protein, and its proteolytic cleavage activity are amplified in K-Ras(G12D) PDECs when assayed by real-time quantitative PCR, ELISA, and fluorescence resonance energy transfer (FRET). Importantly, shRNA silencing of MMP-1 mimics ERK2 inhibition and disrupts active, vertical PDEC invasion. ERK2 isoform and MMP-1 targeting are shown to be viable strategies to attenuate invasion of K-Ras(G12D)-mutated human pancreatic cancer cells in a three-dimensional tumor microenvironment.
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Affiliation(s)
- Gregory P Botta
- Department of Biochemistry and Molecular BiologyDrexel University College of Medicine, Philadelphia, Pennsylvania, USA
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212
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PAK4 phosphorylates myosin regulatory light chain and contributes to Fcγ receptor-mediated phagocytosis. Int J Biochem Cell Biol 2011; 43:1776-81. [DOI: 10.1016/j.biocel.2011.08.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 08/16/2011] [Accepted: 08/25/2011] [Indexed: 01/07/2023]
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213
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Magalhaes MAO, Larson DR, Mader CC, Bravo-Cordero JJ, Gil-Henn H, Oser M, Chen X, Koleske AJ, Condeelis J. Cortactin phosphorylation regulates cell invasion through a pH-dependent pathway. ACTA ACUST UNITED AC 2011; 195:903-20. [PMID: 22105349 PMCID: PMC3257566 DOI: 10.1083/jcb.201103045] [Citation(s) in RCA: 166] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Invadopodia are invasive protrusions with proteolytic activity uniquely found in tumor cells. Cortactin phosphorylation is a key step during invadopodia maturation, regulating Nck1 binding and cofilin activity. The precise mechanism of cortactin-dependent cofilin regulation and the roles of this pathway in invadopodia maturation and cell invasion are not fully understood. We provide evidence that cortactin-cofilin binding is regulated by local pH changes at invadopodia that are mediated by the sodium-hydrogen exchanger NHE1. Furthermore, cortactin tyrosine phosphorylation mediates the recruitment of NHE1 to the invadopodium compartment, where it locally increases the pH to cause the release of cofilin from cortactin. We show that this mechanism involving cortactin phosphorylation, local pH increase, and cofilin activation regulates the dynamic cycles of invadopodium protrusion and retraction and is essential for cell invasion in 3D. Together, these findings identify a novel pH-dependent regulation of cell invasion.
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Affiliation(s)
- Marco A O Magalhaes
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY 10461, USA
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214
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Chen L, Xiao Z, Meng Y, Zhao Y, Han J, Su G, Chen B, Dai J. The enhancement of cancer stem cell properties of MCF-7 cells in 3D collagen scaffolds for modeling of cancer and anti-cancer drugs. Biomaterials 2011; 33:1437-44. [PMID: 22078807 DOI: 10.1016/j.biomaterials.2011.10.056] [Citation(s) in RCA: 205] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 10/20/2011] [Indexed: 01/06/2023]
Abstract
Three-dimensional (3D) culture could partially simulate in vivo conditions. In this work, we developed a 3D collagen scaffold to investigate cellular properties of MCF-7 cells. The porous scaffolds not only induced the diversification of cell morphologies but also extended cell proliferation. The expression of pro-angiogenic growth factors and the transcriptions of matrix metalloproteinases (MMPs) were significantly increased in cells cultured in 3D collagen scaffolds. In addition, 3D collagen scaffolds could generate a cell population with the properties of cancer stem cells (CSCs). The upregulation of EMT markers and the downregulation of the epithelial cell marker were observed in cells cultured in collagen scaffolds. The expression of stem cell markers, including OCT4A and SOX2, and breast cancer stem cell signatures, including SOX4, JAG1 and CD49F, was significantly unregulated in 3D collagen scaffolds. The proportion of cells with CSC-like CD44(+)/CD24(-/low) phenotype was notably increased. High-level expression of CSC-associated properties of MCF-7 cells cultured in 3D was further confirmed by high tumorigenicity in vivo. Moreover, xenografts with 3D cells formed larger tumors. The properties of MCF-7 cells in 3D may have partially simulated their in vivo behaviors. Thus, 3D collagen scaffolds might provide a useful platform for anti-cancer therapeutics and CSC research.
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Affiliation(s)
- Lei Chen
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, PR China
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215
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Friedl P, Alexander S. Cancer Invasion and the Microenvironment: Plasticity and Reciprocity. Cell 2011; 147:992-1009. [DOI: 10.1016/j.cell.2011.11.016] [Citation(s) in RCA: 1419] [Impact Index Per Article: 109.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Indexed: 02/07/2023]
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216
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Myosin II isoform switching mediates invasiveness after TGF-β-induced epithelial-mesenchymal transition. Proc Natl Acad Sci U S A 2011; 108:17991-6. [PMID: 22025714 DOI: 10.1073/pnas.1106499108] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Despite functional significance of nonmuscle myosin II in cell migration and invasion, its role in epithelial-mesenchymal transition (EMT) or TGF-β signaling is unknown. Analysis of normal mammary gland expression revealed that myosin IIC is expressed in luminal cells, whereas myosin IIB expression is up-regulated in myoepithelial cells that have more mesenchymal characteristics. Furthermore, TGF-β induction of EMT in nontransformed murine mammary gland epithelial cells results in an isoform switch from myosin IIC to myosin IIB and increased phosphorylation of myosin heavy chain (MHC) IIA on target sites known to regulate filament dynamics (S1916, S1943). These expression and phosphorylation changes are downstream of heterogeneous nuclear ribonucleoprotein-E1 (E1), an effector of TGF-β signaling. E1 knockdown drives cells into a migratory, invasive mesenchymal state and concomitantly up-regulates MHC IIB expression and MHC IIA phosphorylation. Abrogation of myosin IIB expression in the E1 knockdown cells has no effect on 2D migration but significantly reduced transmigration and macrophage-stimulated collagen invasion. These studies indicate that transition between myosin IIC/myosin IIB expression is a critical feature of EMT that contributes to increases in invasive behavior.
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