301
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Montesano R, Ghzili H, Carrozzino F, Rossier BC, Féraille E. cAMP-dependent chloride secretion mediates tubule enlargement and cyst formation by cultured mammalian collecting duct cells. Am J Physiol Renal Physiol 2008; 296:F446-57. [PMID: 19052103 DOI: 10.1152/ajprenal.90415.2008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polycystic kidney diseases result from disruption of the genetically defined program that controls the size and geometry of renal tubules. Cysts which frequently arise from the collecting duct (CD) result from cell proliferation and fluid secretion. From mCCD(cl1) cells, a differentiated mouse CD cell line, we isolated a clonal subpopulation (mCCD-N21) that retains morphogenetic capacity. When grown in three-dimensional gels, mCCD-N21 cells formed highly organized tubular structures consisting of a palisade of polarized epithelial cells surrounding a cylindrical lumen. Subsequent addition of cAMP-elevating agents (forskolin or cholera toxin) or of membrane-permeable cAMP analogs (CPT-cAMP) resulted in rapid and progressive dilatation of existing tubules, leading to the formation of cystlike structures. When grown on filters, mCCD-N21 cells exhibited a high transepithelial resistance as well as aldosterone- and/or vasopressin-induced amiloride-sensitive and -insensitive current. The latter was in part inhibited by Na(+)-K(+)-2Cl(-) cotransporter (bumetanide) and chloride channel (NPPB) inhibitors. Real-time PCR analysis confirmed the expression of NKCC1, the ubiquitous Na(+)-K(+)-2Cl(-) cotransporter and cystic fibrosis transmembrane regulator (CFTR) in mCCD-N21 cells. Tubule enlargement and cyst formation were prevented by inhibitors of Na(+)-K(+)-2Cl(-) cotransporters (bumetanide or ethacrynic acid) or CFTR (NPPB or CFTR inhibitor-172). These results further support the notion that cAMP signaling plays a key role in renal cyst formation, at least in part by promoting chloride-driven fluid secretion. This new in vitro model of tubule-to-cyst conversion affords a unique opportunity for investigating the molecular mechanisms that govern the architecture of epithelial tubes, as well as for dissecting the pathophysiological processes underlying cystic kidney diseases.
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Affiliation(s)
- Roberto Montesano
- Dept. of Cell Physiology and Metabolism, CMU, rue Michel-Servet, 1, CH-1211 Geneva 4, Switzerland.
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302
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Loss of discordant cells during micro-mass differentiation of embryonic stem cells into the chondrocyte lineage. Cell Death Differ 2008; 16:278-86. [DOI: 10.1038/cdd.2008.149] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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303
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Abelev GI, Eraiser TL. On the path to understanding the nature of cancer. BIOCHEMISTRY (MOSCOW) 2008; 73:487-97. [PMID: 18605973 DOI: 10.1134/s0006297908050015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In this essay crucial problems of the origin of cancer and the development of malignancy are discussed. The problem of precancer and three ways leading to malignancy are considered: induction of tumor precursors, accumulation of genetic traits common for tumor growth, and the role of inflammation in tumor induction. The nature of viral oncogenes and modes of their action are described in the context of their origin as a component of the viral genome. Oncogenes of RNA-containing viruses and DNA-containing tumorigenic viruses are described together with cellular protooncogenes, which are progenitors of RNA-containing viral oncogenes. Hematological malignancies are described as an intermediate form between simple tumors induced by a single oncogene and more complicated epithelial tumors. The roles of tumor suppressor genes and the interaction of several oncogenes in the formation of carcinomas and also the role of progression in tumor evolution are discussed.
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Affiliation(s)
- G I Abelev
- Blokhin Cancer State Research Center, Russian Academy of Medical Sciences, Moscow 115478, Russia.
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304
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Vickers A. Toxicogenomics in Non-Clinical Safety Studies. Genomics 2008. [DOI: 10.3109/9781420067064-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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305
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Differential impact of TGF-β and EGF on fibroblast differentiation and invasion reciprocally promotes colon cancer cell invasion. Cancer Lett 2008; 266:263-74. [DOI: 10.1016/j.canlet.2008.02.068] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 02/26/2008] [Accepted: 02/28/2008] [Indexed: 11/20/2022]
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306
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Jedeszko C, Sameni M, Olive MB, Moin K, Sloane BF. Visualizing protease activity in living cells: from two dimensions to four dimensions. ACTA ACUST UNITED AC 2008; Chapter 4:Unit 4.20. [PMID: 18551423 DOI: 10.1002/0471143030.cb0420s39] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Proteolytic degradation of extracellular matrix (ECM) components by cells is an important metabolic activity as cells grow, remodel, and migrate through the ECM. The ability to analyze ECM degradation can be valuable in the study of developmental processes as well as pathologies, such as cancer. In this unit we describe an in vitro live cell-based method to image and quantitatively measure the degradation of ECM components by live cells. Cells are grown in the presence of fluorescent dye-quenched protein substrates (DQ-gelatin, DQ-collagen I, and DQ-collagen IV) that are mixed with protein matrices. Upon proteolytic cleavage, fluorescence is released that directly reflects the level of proteolysis by the cells. Using confocal microscopy and advanced imaging software, the fluorescence is detected and accurate measurements of proteolytic degradation in three and four dimensions can be assessed.
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Affiliation(s)
- Christopher Jedeszko
- Department of Pharmacology and Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan, USA
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307
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Myers TA, Nickerson CA, Kaushal D, Ott CM, Höner zu Bentrup K, Ramamurthy R, Nelman-Gonzalez M, Pierson DL, Philipp MT. Closing the phenotypic gap between transformed neuronal cell lines in culture and untransformed neurons. J Neurosci Methods 2008; 174:31-41. [PMID: 18672002 DOI: 10.1016/j.jneumeth.2008.06.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 06/18/2008] [Accepted: 06/19/2008] [Indexed: 01/21/2023]
Abstract
Studies of neuronal dysfunction in the central nervous system (CNS) are frequently limited by the failure of primary neurons to propagate in vitro. Neuronal cell lines can be substituted for primary cells but they often misrepresent normal conditions. We hypothesized that a three-dimensional (3D) cell culture system would drive the phenotype of transformed neurons closer to that of untransformed cells, as has been demonstrated in non-neuronal cell lines. In our studies comparing 3D versus two-dimensional (2D) culture, neuronal SH-SY5Y (SY) cells underwent distinct morphological changes combined with a significant drop in their rate of cell division. Expression of the proto-oncogene N-myc and the RNA-binding protein HuD was decreased in 3D culture as compared to standard 2D conditions. We observed a decline in the anti-apoptotic protein Bcl-2 in 3D culture, coupled with increased expression of the pro-apoptotic proteins Bax and Bak. Moreover, thapsigargin (TG)-induced apoptosis was enhanced in the 3D cells. Microarray analysis demonstrated significantly differing mRNA levels for over 700 genes in the cells of the two culture types, and indicated that alterations in the G1/S cell-cycle progression contributed to the diminished doubling rate in the 3D-cultured SY cells. These results demonstrate that a 3D culture approach narrows the phenotypic gap between neuronal cell lines and primary neurons. The resulting cells may readily be used for in vitro research of neuronal pathogenesis.
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Affiliation(s)
- Tereance A Myers
- Division of Bacteriology & Parasitology, Tulane National Primate Research Center, 18703 Three Rivers Road, Covington, LA 70433, USA
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308
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Beningo KA, Wang YL. Double-hydrogel substrate as a model system for three-dimensional cell culture. Methods Mol Biol 2008; 370:203-12. [PMID: 17416996 DOI: 10.1007/978-1-59745-353-0_14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
When cultured on two-dimensional surfaces, most adherent cells show profound differences from those in their native habitats. In addition to chemical factors, it is likely that both physical parameters, such as substrate rigidity, and topographical factors, such as the asymmetry in integrin anchorage, play a major role in the differences. We have designed a simple culture system that provides flexible, adhesive substrates for both dorsal and ventral cell surfaces. Fibroblasts in this system show the spindle or stellate morphology found in native tissues. The ease of preparation, versatility, and optical quality of this model system should greatly facilitate the understanding of cellular behavior and functions in vivo.
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Affiliation(s)
- Karen A Beningo
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA
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309
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Metastatic breast cancer cells colonize and degrade three-dimensional osteoblastic tissue in vitro. Clin Exp Metastasis 2008; 25:741-52. [PMID: 18543066 DOI: 10.1007/s10585-008-9185-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Accepted: 05/20/2008] [Indexed: 12/18/2022]
Abstract
Metastatic breast cancer cells (BCs) colonize a mineralized three-dimensional (3D) osteoblastic tissue (OT) grown from isolated pre-osteoblasts for up to 5 months in a specialized bioreactor. Sequential stages of BC interaction with OT include BC adhesion, penetration, colony formation, and OT reorganization into "Indian files" paralleling BC colonies, heretofore observed only in authentic pathological cancer tissue. BCs permeabilize OT by degrading the extra-cellular collagenous matrix (ECM) in which the osteoblasts are embedded. OT maturity (characterized by culture age and cell phenotype) profoundly affects the patterns of BC colonization. BCs rapidly form colonies on immature OT (higher cell/ECM ratio, osteoblastic phenotype) but fail to completely penetrate OT. By contrast, BCs efficiently penetrate mature OT (lower cell/ECM ratio, osteocytic phenotype) and reorganize OT. BC colonization provokes a strong osteoblast inflammatory response marked by increased expression of the pro-inflammatory cytokine IL-6. Furthermore, BCs inhibit osteoblastic bone formation by down-regulating synthesis of collagen and osteocalcin. Results strongly suggest that breast cancer disrupts the process of osteoblastic bone formation, in addition to upregulating osteoclastic bone resorption as widely reported. These observations may help explain why administration of bisphosphonates to humans with osteolytic metastases slows lesion progression by inhibiting osteoclasts but does not bring about osteoblast-mediated healing.
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310
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Hwang NS, Varghese S, Elisseeff J. Cartilage tissue engineering: Directed differentiation of embryonic stem cells in three-dimensional hydrogel culture. Methods Mol Biol 2008; 407:351-73. [PMID: 18453267 DOI: 10.1007/978-1-59745-536-7_24] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The clinical goal of tissue engineering is to restore, repair, or replace damaged tissues in the body. Significant advances have been made in recent years using stem cells as a cell source for cartilage tissue engineering and reconstructive surgery applications. Embryonic stem cells have demonstrated the potential to self-renew and differentiate into a wide range of tissues including the chondrogenic lineage, depending on culture conditions. Three-dimensional scaffolds play an important role in tissue regeneration by providing attachment sites as well as bioactive signals for cells to grow and differentiate into specific lineages. The precise microenvironments required for optimal expansion or differentiation of stem cells are only beginning to emerge now, and the controlled differentiation of embryonic stem cells in tissue engineering remains a relatively unexplored field. Hydrogels are a class of polymer-based biomaterials that have been extensively utilized in tissue engineering as scaffolds. We have demonstrated that embryonic stem cells encapsulated within poly(ethylene glycol)-based (PEGDA) photopolymerizing hydrogels and cultured in an appropriate growth factor and medium conditions undergo chondrogenic differentiation with extracellular matrix deposition characteristic of neocartilage (Hwang et al., Stem Cells 24, 284-291). Another hydrogel that has been widely used for encapsulating chondrocytes in cartilage tissue engineering is alginate. This hydrogel also has potential for tissue engineering applications using stem cells. Here, we describe the three-dimensional culture of embryonic stem cell-derived embryoid bodies in hydrogels and their differentiation toward chondrogenic lineage in chemically defined chondrogenic medium in the presence of TGF-beta1 (chondrogenic inducing conditions). We also discuss various tools and assays used for characterizing the tissue-engineered cartilage.
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Affiliation(s)
- Nathaniel S Hwang
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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311
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Ivanov AI, Hopkins AM, Brown GT, Gerner-Smidt K, Babbin BA, Parkos CA, Nusrat A. Myosin II regulates the shape of three-dimensional intestinal epithelial cysts. J Cell Sci 2008; 121:1803-14. [PMID: 18460584 DOI: 10.1242/jcs.015842] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The development of luminal organs begins with the formation of spherical cysts composed of a single layer of epithelial cells. Using a model three-dimensional cell culture, this study examines the role of a cytoskeletal motor, myosin II, in cyst formation. Caco-2 and SK-CO15 intestinal epithelial cells were embedded into Matrigel, and myosin II was inhibited by blebbistatin or siRNA-mediated knockdown. Whereas control cells formed spherical cysts with a smooth surface, inhibition of myosin II induced the outgrowth of F-actin-rich surface protrusions. The development of these protrusions was abrogated after inhibition of F-actin polymerization or of phospholipase C (PLC) activity, as well as after overexpression of a dominant-negative ADF/cofilin. Surface protrusions were enriched in microtubules and their formation was prevented by microtubule depolymerization. Myosin II inhibition caused a loss of peripheral F-actin bundles and a submembranous extension of cortical microtubules. Our findings suggest that inhibition of myosin II eliminates the cortical F-actin barrier, allowing microtubules to reach and activate PLC at the plasma membrane. PLC-dependent stimulation of ADF/cofilin creates actin-filament barbed ends and promotes the outgrowth of F-actin-rich protrusions. We conclude that myosin II regulates the spherical shape of epithelial cysts by controlling actin polymerization at the cyst surface.
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Affiliation(s)
- Andrei I Ivanov
- Epithelial Pathobiology Research Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, USA.
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312
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Lamellipodia and filopodia in metastasis and invasion. FEBS Lett 2008; 582:2102-11. [DOI: 10.1016/j.febslet.2008.03.039] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 03/31/2008] [Indexed: 01/20/2023]
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313
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Cullen DK, Vukasinovic J, Glezer A, LaPlaca MC. High cell density three-dimensional neural co-cultures require continuous medium perfusion for survival. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; 2006:636-9. [PMID: 17946846 DOI: 10.1109/iembs.2006.260639] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Three-dimensional (3-D) models of neural cell culture may provide researchers with a more physiologically-relevant setting to study neurobiological phenomena than traditional two-dimensional (2-D) culture models. However, in the development of thick (>500 microm) 3-D cultures, diffusion limited mass transport necessitated the use of cell densities much lower than those found in the central nervous system (CNS). The goal of this study was to evaluate the effects of continuous medium perfusion on the survival of thick, 3-D neuronal-astrocytic co-cultures at cell densities closer to those found in brain tissue. At the cell density and thickness used for these studies, 10(4) cells/mm(3) and 500-750 microm, respectively, non-perfused cultures exhibited widespread cellular/matrix degradation and cell death. However, co-cultures perfused at relatively high rates (2.5-11.0 microL/min, corresponding to 6-27 medium exchanges/day) demonstrated decreased degradation and enhanced viability compared to non-perfused co-cultures. Furthermore, the highest perfusion rate evaluated, 11.0 microL/min, resulted in >90% cell viability and maintenance of culture thickness. Next generation 3-D neural cultures, with cell types and densities better approximating the CNS, may provide enhanced model fidelity and be valuable in the mechanistic study of cell growth, interactions, and the responses to chemical or mechanical perturbations.
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Affiliation(s)
- D Kacy Cullen
- Dept. of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0535, USA.
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314
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Zhang S. Designer self-assembling Peptide nanofiber scaffolds for study of 3-d cell biology and beyond. Adv Cancer Res 2008; 99:335-62. [PMID: 18037409 DOI: 10.1016/s0065-230x(07)99005-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Biomedical researchers have become increasingly aware of the limitations of the conventional 2-D tissue cell cultures where most tissue cell studies including cancer and tumor cells have been carried out. They are now searching and testing 3-D cell culture systems, something between a petri dish and a mouse. The important implications of 3-D tissue cell cultures for basic cell biology, tumor biology, high-content drug screening, and regenerative medicine and beyond are far-reaching. How can nanobiotechnology truly advance the traditional cell, tumor, and cancer biology? Why nano is important in biomedical research and medical science? A nanometer is 1000 times smaller than a micrometer, but why it matters in biology? This chapter addresses these questions. It has become more and more apparent that 3-D cell culture offers a more realistic local environment through the nanofiber scaffolds where the functional properties of cells can be observed and manipulated. A new class of designer self-assembling peptide nanofiber scaffolds now provides an ideal alternative system. Time has come to address the 3-D questions because quantitative biology requires in vitro culture systems that more authentically represent the cellular microenvironment in a living organism. In doing so, in vitro experimentation can become truly more predictive of in vivo systems.
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Affiliation(s)
- Shuguang Zhang
- Center for Biomedical Engineering NE47-379, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
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315
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Pearson GW, Hunter T. Real-time imaging reveals that noninvasive mammary epithelial acini can contain motile cells. ACTA ACUST UNITED AC 2008; 179:1555-67. [PMID: 18166657 PMCID: PMC2373504 DOI: 10.1083/jcb.200706099] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
To determine how extracellular signal–regulated kinases (ERK) 1/2 promote mammary tumorigenesis, we examined the real-time behavior of cells in an organotypic culture of the mammary glandular epithelium. Inducible activation of ERK1/2 in mature acini elicits cell motility and disrupts epithelial architecture in a manner that is reminiscent of ductal carcinoma in situ; however, motile cells do not invade through the basement membrane and branching morphogenesis does not take place. ERK1/2-induced motility causes cells to move both within the cell monolayer that contacts the basement membrane surrounding the acinus and through the luminal space of the acinus. E-cadherin expression is reduced after ERK1/2 activation, but motility does not involve an epithelial–mesenchymal transition. Cell motility and the disruption of epithelial architecture require a Rho kinase– and myosin light chain kinase–dependent increase in the phosphorylation of myosin light chain 2. Our results identify a new mechanism for the disruption of architecture in epithelial acini and suggest that ERK1/2 can promote noninvasive motility in preinvasive mammary tumors.
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Affiliation(s)
- Gray W Pearson
- Molecular and Cell Biology Laboratory, Salk Institute, La Jolla, CA 92037, USA
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316
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Cullen DK, Stabenfeldt SE, Simon CM, Tate CC, LaPlaca MC. In vitro neural injury model for optimization of tissue-engineered constructs. J Neurosci Res 2008; 85:3642-51. [PMID: 17671988 DOI: 10.1002/jnr.21434] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Stem cell transplantation is a promising approach for the treatment of traumatic brain injury, although the therapeutic benefits are limited by a high degree of donor cell death. Tissue engineering is a strategy to improve donor cell survival by providing structural and adhesive support. However, optimization prior to clinical implementation requires expensive and time-consuming in vivo studies. Accordingly, we have developed a three-dimensional (3-D) in vitro model of the injured host-transplant interface that can be used as a test bed for high-throughput evaluation of tissue-engineered strategies. The neuronal-astrocytic cocultures in 3-D were subjected to mechanical loading (inducing cell death and specific astrogliotic alterations) or to treatment with transforming growth factor-beta1 (TGF-beta1), inducing astrogliosis without affecting viability. Neural stem cells (NSCs) were then delivered to the cocultures. A sharp increase in the number of TUNEL(+) donor cells was observed in the injured cocultures compared to that in the TGF-beta1-treated and control cocultures, suggesting that factors related to mechanical injury, but not strictly astrogliosis, were detrimental to donor cell survival. We then utilized the mechanically injured cocultures to evaluate a methylcellulose-laminin (MC-LN) scaffold designed to reduce apoptosis. When NSCs were co-delivered with MC alone or MC-LN to the injured cocultures, the number of caspase(+) donor cells significantly decreased compared to that with vehicle delivery (medium). Collectively, these results demonstrate the utility of an in vitro model as a pre-animal test bed and support further investigation of a tissue-engineering approach for chaperoned NSC delivery targeted to improve donor cell survival in neural transplantation.
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Affiliation(s)
- D Kacy Cullen
- Wallace H. Coulter Department of Biomedical Engineering, Institute for Bioengineering and Bioscience, Laboratory for Neuroengineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA 30332, USA
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317
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Friedrich J, Eder W, Castaneda J, Doss M, Huber E, Ebner R, Kunz-Schughart LA. A reliable tool to determine cell viability in complex 3-d culture: the acid phosphatase assay. ACTA ACUST UNITED AC 2008; 12:925-37. [PMID: 17942785 DOI: 10.1177/1087057107306839] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cell-based assays are more complex than cell-free test systems but still reflect a highly artificial cellular environment. Incorporation of organotypic 3-dimensional (3-D) culture systems into mainstream drug development processes is increasingly discussed but severely limited by complex methodological requirements. The objective of this study was to explore a panel of standard assays to provide an easy-handling, standardized protocol for rapid routine analysis of cell survival in multicellular tumor spheroid-based antitumor drug testing. Spheroids of 2 colon carcinoma cell lines were characterized for evaluation. One of the assay systems tested could reliably be used to determine cell viability in spheroids. The authors verified that the acid phosphatase assay (APH) is applicable for single spheroids in 96-well plates, does not require spheroid dissociation, and is linear and highly sensitive for HT29 and HCT-116 spheroids up to diameters of 650 microm and 900 microm, consisting of 40,000 and 80,000 cells, respectively. Treatment of HT29 and HCT-116 cells with 5-fluorouracil, Irinotecan, and C-1311 revealed critically reduced drug efficacies in 3-D versus monolayer culture, which is discussed in light of literature data. The experimental protocol presented herein is a small but substantial contribution to the establishment of sophisticated 3-D in vitro systems in the antitumor drug screening scenario.
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Affiliation(s)
- Juergen Friedrich
- Institute of Pathology, University of Regensburg, Regensburg, Germany
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318
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Smith LA, Liu X, Ma PX. Tissue Engineering with Nano-Fibrous Scaffolds. SOFT MATTER 2008; 4:2144-2149. [PMID: 20052297 PMCID: PMC2801146 DOI: 10.1039/b807088c] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Tissue Engineering is a rapidly evolving field in terms of cell source and scaffold fabrication. As the template for three dimensional tissue growth, the scaffold should emulate the native extracellular matrix, which is nano-fibrous. Currently, there are three basic techniques capable of generating nano-fibrous scaffolding: electrospinning, molecular self-assembly, and thermally induced phase separation. These scaffolds can then be further modified by various three dimensional surface modification techniques if necessary to more precisely emulate the native extracellular matrix. However, even without further modification, nano-fibrous scaffolds have been shown to have advantageous effects on cellular behavior and tissue formation when compared to more traditional types of scaffolding. This review focuses on the current state of tissue engineering with nano-fibrous scaffolding with particular emphasis on bone tissue engineering.
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Affiliation(s)
- Laura A. Smith
- Department of Biomedical Engineering, University of Michigan, 1011 North University, Ann Arbor, MI 4810 USA
| | - Xiaohua Liu
- Biological and material Sciences, University of Michigan, 1011 North University, Ann Arbor, MI 4810 USA
| | - Peter X. Ma
- Department of Biomedical Engineering, University of Michigan, 1011 North University, Ann Arbor, MI 4810 USA
- Biological and material Sciences, University of Michigan, 1011 North University, Ann Arbor, MI 4810 USA
- Macromolecular Sciences and Engineering, University of Michigan, 1011 North University, Ann Arbor, MI 4810 USA. Fax 734-647-2110; Tel: 734-764-2209; E-mail:
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319
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Sawyer N, Worrall L, Crowe J, Waters S, Shakesheff K, Rose F, Morgan S. In situ monitoring of 3D in vitro cell aggregation using an optical imaging system. Biotechnol Bioeng 2008; 100:159-67. [DOI: 10.1002/bit.21728] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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320
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Hebner C, Weaver VM, Debnath J. Modeling morphogenesis and oncogenesis in three-dimensional breast epithelial cultures. ANNUAL REVIEW OF PATHOLOGY 2008; 3:313-339. [PMID: 18039125 DOI: 10.1146/annurev.pathmechdis.3.121806.151526] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Three-dimensional (3D) epithelial culture systems recreate the cardinal features of glandular epithelium in vivo and represent a valuable tool for modeling breast cancer initiation and progression in a structurally appropriate context. 3D models have emerged as a powerful method to interrogate the biological activities of cancer genes and oncogenic pathways, and recent studies have poignantly illustrated their utility in dissecting the emerging role of tensional force in regulating epithelial tissue homeostasis. We review how 3D models are being used to investigate fundamental cellular and biophysical mechanisms associated with breast cancer progression that have not been readily amenable to traditional genetic or biochemical analysis.
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Affiliation(s)
- Christy Hebner
- Department of Surgery and Center for Bioengineering and Tissue Regeneration, University of California, San Francisco, CA, USA.
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321
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Elberg G, Guruswamy S, Logan CJ, Chen L, Turman MA. Plasticity of epithelial cells derived from human normal and ADPKD kidneys in primary cultures. Cell Tissue Res 2007; 331:495-508. [DOI: 10.1007/s00441-007-0521-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Accepted: 09/20/2007] [Indexed: 11/28/2022]
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322
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Doumèche B, Picard J, Larreta-Garde V. Enzyme-catalyzed phase transition of alginate gels and gelatin-alginate interpenetrated networks. Biomacromolecules 2007; 8:3613-8. [PMID: 17949036 DOI: 10.1021/bm700767u] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The enzyme-catalyzed gel-sol transition of calcium-alginate obtained by internal gelling strategy with the help of an entrapped alginate lyase is described. We show that alginate molecules and enzyme-produced oligoalginates shorten the gel time of physical gelatin gels (5% and 1.5%), probably due to local protein concentration increase. Interpenetrated networks composed of calcium-alginate and of gelatin were obtained only if elongation of gelatin helices inside a pre-existing calcium-alginate network could occur and only for low gelatin concentration (1.5%). The physical gelatin network is almost reversible inside the alginate one. Both networks can be obtained in the presence of alginate lyase, but gel-sol transition of calcium-alginate cannot be obtained in the presence of gelatin.
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Affiliation(s)
- Bastien Doumèche
- Laboratoire ERRMECe UFR Sciences et Techniques Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, Pontoise cedex, France
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323
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Abstract
Pancreatic cancer is the fifth leading cause of adult cancer death in the United States, with 5-year survival rates of only 1% to 4%. Current therapeutic strategies generally result in only a few months of extended life. Recent evidence from several independent laboratories in vitro and in vivo indicate that integrin-mediated cell attachment to the extracellular matrix (ECM), components of which are highly up-regulated in pancreatic cancer, evokes phenotypes and signaling pathways that regulate tumor cell growth and migration. In this review, we will discuss our current understanding of the role of the ECM in directing pancreatic cancer growth, progression, and metastasis. Topics covered include a survey of the existing literature regarding the in vivo and in vitro expression of the ECM and its cell surface receptors, the integrins, in pancreatic cancer; mechanisms involved in the integrin-ECM-mediated malignant phenotype; and future directions for the study of the integrin-ECM axis and its role in pancreatic cancer progression, including potential therapeutic strategies.
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324
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Bissell MJ. Architecture Is the Message: The role of extracellular matrix and 3-D structure in tissue-specific gene expression and breast cancer. THE PEZCOLLER FOUNDATION JOURNAL : NEWS FROM THE PEZCOLLER FOUNDATION WORLD 2007; 16:2-17. [PMID: 21132084 PMCID: PMC2995891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
I was honored to deliver the 2(nd) Stanley Korsmeyer memorial Lecture on May 9(th), 2007 in Padova, Italy. Stan will always occupy a very special place in my heart: I admired him greatly not only for his magnificent and original science but also for his integrity and his grace. This review, which summarizes my laboratory's contribution to cell and cancer biology in the last 30 years, is dedicated to Stan's memory, and to Elaine Fuchs, one of my most cherished friends without whose support this work would not have gained the degree of recognition it enjoys today. My thanks also to the Pezcoller Foundation for making that week in May, 2007 one of the most memorable in my scientific life.
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325
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Bokhari M, Carnachan RJ, Cameron NR, Przyborski SA. Culture of HepG2 liver cells on three dimensional polystyrene scaffolds enhances cell structure and function during toxicological challenge. J Anat 2007; 211:567-76. [PMID: 17711423 PMCID: PMC2375833 DOI: 10.1111/j.1469-7580.2007.00778.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2007] [Indexed: 11/27/2022] Open
Abstract
Cultured cells are dramatically affected by the micro-environment in which they are grown. In this study, we have investigated whether HepG2 liver cells grown in three dimensional (3-D) cultures cope more effectively with the known cytotoxic agent, methotrexate, than their counterparts grown on traditional two dimensional (2-D) flat plastic surfaces. To enable 3-D growth of HepG2 cells in vitro, we cultured cells on 3-D porous polystyrene scaffolds previously developed in our laboratories. HepG2 cells grown in 3-D displayed excellent morphological characteristics and formed numerous bile canaliculi that were seldom seen in cultures grown on 2-D surfaces. The function of liver cells grown on 3-D supports was significantly enhanced compared to activity of cells grown on 2-D standard plasticware. Unlike their 2-D counterparts, 3-D cultures were less susceptible to lower concentrations of methotrexate. Cells grown in 3-D maintained their structural integrity, possessed greater viability, were less susceptible to cell death at higher levels of the cytotoxin compared to 2-D cultures, and appeared to respond to the drug in a manner more comparable to its known activity in vivo. Our results suggest that hepatotoxicity testing using 3-D cultures might be more likely to reflect true physiological responses to cytotoxic compounds than existing models that rely on 2-D culture systems. This technology has potential applications for toxicity testing and drug screening.
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Affiliation(s)
- Maria Bokhari
- School of Biological and Biomedical Science, Durham University, South Road, Durham DH1 3LE, UK
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326
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De Bank PA, Hou Q, Warner RM, Wood IV, Ali BE, Macneil S, Kendall DA, Kellam B, Shakesheff KM, Buttery LDK. Accelerated formation of multicellular 3-D structures by cell-to-cell cross-linking. Biotechnol Bioeng 2007; 97:1617-25. [PMID: 17304565 DOI: 10.1002/bit.21343] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The three-dimensional (3-D) arrangement of cells within tissues is integral to their development and function. Advances in stem cell science and regenerative medicine have stimulated interest in the replication of this architecture in vitro. We have developed a versatile method for controlling short-term cell-cell and cell-matrix interactions via a facile cell surface engineering process that enables the rapid formation of specific 3-D interactions for a range of cell types. We demonstrate that chemical modification of cell surfaces and matrix proteins can artificially accelerate the cell adhesion process and confirm the ability to control the formation of multicellular aggregates with defined architectures and heterotypic cell types. Direct comparison with a natural aggregation process seen during differentiation of embryonic stem (ES) cells revealed increased expression of developmental regulatory proteins and a concomitant enhancement of ES cell differentiation. Furthermore, this new methodology has numerous applications in generating layered structures. For example, we demonstrate improved transfer of therapeutic human keratinocytes onto a dermal layer in a skin repair model.
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Affiliation(s)
- Paul A De Bank
- Department of Pharmacy & Pharmacology, University of Bath, Bath BA2 7AY, UK
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327
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Raeber GP, Lutolf MP, Hubbell JA. Mechanisms of 3-D migration and matrix remodeling of fibroblasts within artificial ECMs. Acta Biomater 2007; 3:615-29. [PMID: 17572164 DOI: 10.1016/j.actbio.2007.03.013] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Revised: 03/19/2007] [Accepted: 03/27/2007] [Indexed: 01/30/2023]
Abstract
The elucidation of molecular cell-extracellular matrix (ECM) interactions regulating tissue dynamics necessitates straightforward model systems that can dissect the associated physiological complexity into a smaller number of distinct interactions. Here we employ a previously developed artificial ECM model system to study dynamic cell-matrix interactions involved in proteolytic three-dimensional (3-D) migration and matrix remodeling at the level of single cells. Quantitative time-lapse microscopy of primary human fibroblasts exposed to exogenous physiological matrix metalloproteinase (MMP) inhibitors revealed that 3-D migration is dependent on cell seeding density and occurred via highly localized MMP- and tissue inhibitor of metalloproteinases-2-dependent processes. Stimulation of cells by tumor necrosis factor alpha led to a striking augmentation in fibroblast migration that was accompanied by induction of alphaVbeta3 integrin expression. In long-term cultures, extensive localized cellular matrix remodeling resulted in the morphogenesis of single cells into interconnected multicellular networks. Therefore, these tailor-made artificial ECMs can replicate complex 3-D cell-matrix interactions involved in tissue development and regeneration, an important step in the design of next-generation synthetic biomaterials for tissue engineering.
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Affiliation(s)
- G P Raeber
- Institute of Bioengineering and Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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328
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Partanen JI, Nieminen AI, Mäkelä TP, Klefstrom J. Suppression of oncogenic properties of c-Myc by LKB1-controlled epithelial organization. Proc Natl Acad Sci U S A 2007; 104:14694-9. [PMID: 17766436 PMCID: PMC1976192 DOI: 10.1073/pnas.0704677104] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Cellular organization into epithelial architecture maintains structural integrity and homeostasis by suppressing cell proliferation and apoptosis. However, it is unclear whether the epithelial organization is sufficient to block induction of cell-autonomous cell cycle progression and apoptotic sensitivity by activated oncogenes. We show that chronic activation of oncogenic c-Myc, starting in the developing 3D organotypic mammary acinar structures, results in hyperproliferation and transformed acinar morphology. Surprisingly, acute c-Myc activation in mature quiescent acini with established epithelial architecture fails to reinitiate the cell cycle or transform these structures. c-Myc does reinitiate the cell cycle in quiescent, but structurally unorganized, acini, which demonstrates that proper epithelial architecture is needed for the proliferation blockade. The capability of c-Myc to reinitiate the cell cycle in acinar structures is also restored by the loss of LKB1, a human homologue of the cell polarity protein PAR4. The epithelial architecture also restrains the apoptotic activity of c-Myc, but coactivation of c-Myc and a complementary TNF-related apoptosis-inducing ligand death receptor pathway can induce a strong Bim and Bid-mediated apoptotic response in the established acini. The results together expose surprising proliferation and apoptosis resistance of organized epithelial structures and identify a role for the polarity regulator LKB1 in the development of c-Myc-resistant cell organization.
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Affiliation(s)
- Johanna I. Partanen
- Cancer Cell Circuitry Laboratory, Institute of Biomedicine/Biochemistry and Genome-Scale Biology Program, Biomedicum Helsinki, University of Helsinki, Room B231a, P.O Box 63, Haartmaninkatu 8, 00014, Helsinki, Finland
| | - Anni I. Nieminen
- Cancer Cell Circuitry Laboratory, Institute of Biomedicine/Biochemistry and Genome-Scale Biology Program, Biomedicum Helsinki, University of Helsinki, Room B231a, P.O Box 63, Haartmaninkatu 8, 00014, Helsinki, Finland
| | - Tomi P. Mäkelä
- Cancer Cell Circuitry Laboratory, Institute of Biomedicine/Biochemistry and Genome-Scale Biology Program, Biomedicum Helsinki, University of Helsinki, Room B231a, P.O Box 63, Haartmaninkatu 8, 00014, Helsinki, Finland
| | - Juha Klefstrom
- Cancer Cell Circuitry Laboratory, Institute of Biomedicine/Biochemistry and Genome-Scale Biology Program, Biomedicum Helsinki, University of Helsinki, Room B231a, P.O Box 63, Haartmaninkatu 8, 00014, Helsinki, Finland
- *To whom correspondence should be addressed. E-mail:
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329
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Three-dimensional polymeric systems for cancer cell studies. Cytotechnology 2007; 54:135-43. [PMID: 19003005 DOI: 10.1007/s10616-007-9065-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Accepted: 02/27/2007] [Indexed: 12/31/2022] Open
Abstract
Three-dimensional (3-D) culture of cancer cells and of normal mammalian cells in a polymeric matrix is generally a better alternate model for understanding the regulation of cancer cell proliferation and for evaluation of different anticancer drugs. A substantial amount of evidence demonstrates important differences in the behavior of cells grown in monolayer, i.e., two-dimensional (2-D), and in 3-D cultures. Cancer cells grown in 3-D culture are more resistant to cytotoxic agents than cells in 2-D culture; growth of cells in vitro in 3-D requires a suitable polymer that provides a structural scaffold for cell adhesion and growth. Many naturally derived polymers as well as synthetic polymers have been investigated as scaffolds. The aim of this review is to overview the polymeric materials of natural and synthetic origin that are of specific interest to 3-D cell cultures, and discuss the development of new polymers that should be specifically designed for 3-D culture applications.
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330
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Liu Y, Shu XZ, Prestwich GD. Tumor engineering: orthotopic cancer models in mice using cell-loaded, injectable, cross-linked hyaluronan-derived hydrogels. ACTA ACUST UNITED AC 2007; 13:1091-101. [PMID: 17582839 DOI: 10.1089/ten.2006.0297] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Current cancer xenograft models used to evaluate new anticancer therapies are limited to "good take" cell lines, fail to mimic normal human disease, and poorly predict clinical outcomes. We now describe the use of an injectable, in situ cross-linkable synthetic extracellular matrix (sECM) to deliver and grow cancer cells in vivo. The hyaluronan (HA)-derived sECMs were seeded with breast, colon, and ovarian cancer cells prior to gelation, and then injected subcutaneously into mammary fat pads, subserosally in colons, and intracapsularly in ovaries, respectively. Two cell lines were used for each type of cancer, and results were compared with orthotopic injection of cells in serum-free medium. At 4 weeks postinjection, four parameters were measured: (i) incidence and size of cancer at the injection site, (ii) vascularization or necrosis of new cancer tissue, (iii) cancer seeding in adjacent tissues, and (iv) metastasis to lymph nodes and other vital organs. In addition, the activation of the phosphoinositide 3-kinase (PI 3-K) signaling pathway was analyzed immunohistochemically. Overall, orthotopic delivery of cancer cells in sECM hydrogels showed clear advantages: (i) increased incidence of cancer formation and reduced variability in tumor size, (ii) enhanced growth of organ-specific cancers with good tumor-tissue integration, (iii) improved vascularization and reduced necrosis within the tumor, (iv) reduced cancer seeding on adjacent tissues, and (v) better general health of animals. Thus, engineered tumors represent an improved approach to traditional tumor xenografts, and facilitate studies in cancer biology, invasion and metastasis, as well as the investigation of new therapeutic and diagnostic protocols.
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Affiliation(s)
- Yanchun Liu
- Center for Therapeutic Biomaterials and Department of Medicinal Chemistry, The University of Utah, Salt Lake City 84108-1257, USA
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331
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Walles T, Weimer M, Linke K, Michaelis J, Mertsching H. The Potential of Bioartificial Tissues in Oncology Research and Treatment. Oncol Res Treat 2007; 30:388-94. [PMID: 17596750 DOI: 10.1159/000102544] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This review article addresses the relevance and potential of bioartificial tissues in oncologic research and therapy and reconstructive oncologic surgery. In order to translate the findings from basic cellular research into clinical applications, cell-based models need to recapitulate both the 3D organization and multicellular complexity of an organ but at the same time accommodate systematic experimental intervention. Here, tissue engineering, the generation of human tissues and organs in vitro, provides new perspectives for basic and applied research by offering 3D tissue cultures resolving fundamental obstacles encountered in currently applied 2D and 3D cell culture systems. Tissue engineering has already been applied to create replacement structures for reconstructive surgery. Applied in vitro, these complex multicellular 3D tissue cultures mimic the microenvironment of human tissues. In contrast to the currently available cell culture systems providing only limited insight into the complex interactions in tissue differentiation, carcinogenesis, angiogenesis and the stromal reaction, the more realistic (micro)environment afforded by the bioartificial tissuespecific 3D test systems may accelerate the progress in design and development of cancer therapies.
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Affiliation(s)
- Thorsten Walles
- Abteilung für Thoraxchirurgie, Klinik Schillerhöhe, Gerlingen, Germany
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332
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Wentzensen N, Braumann UD, Einenkel J, Horn LC, von Knebel Doeberitz M, Löffler M, Kuska JP. Combined serial section-based 3D reconstruction of cervical carcinoma invasion using H&E/p16INK4a/CD3 alternate staining. Cytometry A 2007; 71:327-33. [PMID: 17279561 DOI: 10.1002/cyto.a.20385] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Malignant growth and invasiveness of cancers is a function of both intratumoral and stromal factors. The accessibility to nutrients, oxygen and growth factors, the stromal composition, and the interference with the immune system all shape the tumor invasion front. A recent study has shown a prognostic difference with respect to different invasion patterns analyzed on histological specimens of cervical cancers. The present study analyzes the spatial organization of a cervical cancer and the relation of the tumor invasion front and the infiltration with CD3(+) T-cells. METHODS From a cervical squamous cell carcinoma specimen, 84 serial sections were performed and three interleaving series were stained with hematoxylin/eosin and immunohistochemistry directed against the cervical carcinoma biomarker p16(INK4a) and the T-cell marker CD3. Sections were passed through an image processing chain to obtain a reconstructed and segmented tissue volume. For local tumor invasion front analysis the mean curvature was used, which in turn was related to the respective local minimum tumor to T-cell distance as well to a T-cell originated diffusing substance's concentration at the tumor surface. RESULTS Spatial models of the tumor tissue and the infiltrating T-cells were computed. The overall discrete compactness of the tumor invasion front was 0.89, corresponding to a pathological assessment of diffuse infiltration. The comparison of the tumor invasion front with the density of T-cell infiltration revealed an increased smoothening in regions with high T-cell infiltration. CONCLUSIONS We could demonstrate the spatial organization of a cervical cancer and model the interaction between infiltrating T-cells with the tumor invasion front shape. Increased smoothening in regions with high T-cell infiltration suggests that T-cells may have an influence on the shaping of the tumor invasion front, e.g., by attacking tumor cells displaying specific antigens. The applied technique allows visualization of the spatial organization of tissues and could be extended to analyze multiple stains on alternating sections.
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Affiliation(s)
- Nicolas Wentzensen
- Division for Applied Tumor Biology, Institute of Pathology, University Heidelberg, 69120 Heidelberg, Germany
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333
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Na K, Kim SW, Sun BK, Woo DG, Yang HN, Chung HM, Park KH. Osteogenic differentiation of rabbit mesenchymal stem cells in thermo-reversible hydrogel constructs containing hydroxyapatite and bone morphogenic protein-2 (BMP-2). Biomaterials 2007; 28:2631-7. [PMID: 17331575 DOI: 10.1016/j.biomaterials.2007.02.008] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 02/08/2007] [Indexed: 01/16/2023]
Abstract
The aim of this study was to assess the efficacy of ectopic bone formation in a three-dimensional hybrid scaffold in combination with hydroxyapatite (HA) and poly(NiPAAm-co-AAc) as an injectable vehicle in the form of a supporting matrix for the osteogenic differentiation of rabbit mesenchymal stem cells (MSCs). Osteogenic differentiation of MSCs in the hybrid scaffold was greatly influenced by the addition of growth factors. When the osteoinduction activity of hybrid scaffold was studied following implantation into the back subcutis of nude mouse in terms of histological and biochemical examinations, significantly homogeneous bone formation was histologically observed throughout the hybrid scaffolds containing growth factor (BMP-2: bone morphogenic protein-2). The level of alkaline phosphatase activity and osteocalcin content at the implanted sites of hybrid scaffolds were significantly high for the perfusion group compared with those in static culture group. We conclude that combination of MSC-seeded hybrid scaffold containing BMP-2 was a promising method by which to enhance in vitro osteogenic differentiation of MSC and in vivo ectopic bone formation.
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Affiliation(s)
- Kun Na
- Division of Biotechnology, The Catholic University of Korea, 43-1 Yokkok2-dong, Wonmi-gu, Bucheon 420-743, Republic of Korea
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334
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Cullen DK, Vukasinovic J, Glezer A, Laplaca MC. Microfluidic engineered high cell density three-dimensional neural cultures. J Neural Eng 2007; 4:159-72. [PMID: 17409489 DOI: 10.1088/1741-2560/4/2/015] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Three-dimensional (3D) neural cultures with cells distributed throughout a thick, bioactive protein scaffold may better represent neurobiological phenomena than planar correlates lacking matrix support. Neural cells in vivo interact within a complex, multicellular environment with tightly coupled 3D cell-cell/cell-matrix interactions; however, thick 3D neural cultures at cell densities approaching that of brain rapidly decay, presumably due to diffusion limited interstitial mass transport. To address this issue, we have developed a novel perfusion platform that utilizes forced intercellular convection to enhance mass transport. First, we demonstrated that in thick (>500 microm) 3D neural cultures supported by passive diffusion, cell densities <or=5.0 x 10(3) cells mm(-3) were required for survival. In 3D neuronal and neuronal-astrocytic co-cultures with increased cell density (10(4) cells mm(-3)), continuous medium perfusion at 2.0-11.0 microL min(-1) improved viability compared to non-perfused cultures (p < 0.01), which exhibited widespread cell death and matrix degradation. In perfused cultures, survival was dependent on proximity to the perfusion source at 2.00-6.25 microL min(-1) (p < 0.05); however, at perfusion rates of 10.0-11.0 microL min(-1) survival did not depend on the distance from the perfusion source, and resulted in a preservation of cell density with >90% viability in both neuronal cultures and neuronal-astrocytic co-cultures. This work demonstrates the utility of forced interstitial convection in improving the survival of high cell density 3D engineered neural constructs and may aid in the development of novel tissue-engineered systems reconstituting 3D cell-cell/cell-matrix interactions.
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Affiliation(s)
- D Kacy Cullen
- Wallace H Coulter Department of Biomedical Engineering, Parket H Petit Institute for Bioengineering and Bioscience, Laboratory for Neuroengineering, Georgia Institute of Technology, Atlanta, GA, USA.
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335
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Jack GD, Cabrera MC, Manning ML, Slaughter SM, Potts M, Helm RF. Activated stress response pathways within multicellular aggregates utilize an autocrine component. Cell Signal 2007; 19:772-81. [PMID: 17127033 DOI: 10.1016/j.cellsig.2006.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 09/26/2006] [Accepted: 10/01/2006] [Indexed: 01/15/2023]
Abstract
Multicellular aggregates (spheroids) of primary human foreskin fibroblasts (HFF-2) and a glioblastoma cell line (T98G) entered and exited from long term (2 weeks) metabolic arrest utilizing an autocrine response. Cytokine production (specifically IFN-gamma) activated a Gadd45alpha/p38 pathway that led to increased AP-1 (c-jun and ATF3) transcription factor levels, augmenting cytokine production in an autocrine fashion. Whereas HFF-2 aggregates were capable of surviving long term arrest and recovery during NF-kappaB inhibition independent of JNK activation, T98G aggregates were not. Such endogenous processes are not easily observed with adherent monolayer cell culturing systems, strongly suggesting that more emphasis needs to be placed on determining the operational signal transduction cascades within multicellular aggregates. Extracellular inputs such as spheroid formation, arrest, and regrowth as monolayers invoke intracellular signaling responses converging at the AP-1 transcription factor level. Variations in responses are both cell type and transformation state dependent and require an autocrine cytokine component. The data are discussed in relation to the wounding response and avascular tumor growth mechanisms.
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Affiliation(s)
- Graham D Jack
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
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336
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Cullen DK, Lessing MC, LaPlaca MC. Collagen-dependent neurite outgrowth and response to dynamic deformation in three-dimensional neuronal cultures. Ann Biomed Eng 2007; 35:835-46. [PMID: 17385044 DOI: 10.1007/s10439-007-9292-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 03/02/2007] [Indexed: 10/23/2022]
Abstract
In vitro models of brain injury that use thick 3-D cultures and control extracellular matrix constituents allow evaluation of cell-matrix interactions in a more physiologically relevant configuration than traditional 2-D cultures. We have developed a 3-D cell culture system consisting of primary rat cortical neurons distributed throughout thick (>500 microm) gels consisting of type IV collagen (Col) conjugated to agarose. Neuronal viability and neurite outgrowth were examined for a range of agarose (AG) percentages (1.0-3.0%) and initial collagen concentrations ([Col](i); 0-600 microg/mL). In unmodified AG, 1.5% gels supported viable cultures with significant neurite outgrowth, which was not found at lower (< or =1.0%) concentrations. Varying [Col](i )in 1.25% AG revealed the formation of dense, 3-D neurite networks at [Col](i) of 300 microg/mL, while neurons in unmodified AG and at higher [Col](i) (600 microg/mL) exhibited significantly less neurite outgrowth; although, neuronal survival did not vary with [Col](i). The effect of [Col](i) on acute neuronal response following high magnitude, high rate shear deformation (0.50 strain, 30 s(-1) strain rate) was evaluated in 1.5% AG for [Col](i) of 30, 150, and 300 microg/mL, which supported cultures with similar baseline viability and neurite outgrowth. Conjugation of Col to AG also increased the complex modulus of the hydrogel. Following high rate deformation, neuronal viability significantly decreased with increasing [Col](i), implicating cell-matrix adhesions in acute mechanotransduction events associated with traumatic loading. These results suggest interrelated roles for matrix mechanical properties and receptor-mediated cell-matrix interactions in neuronal viability, neurite outgrowth, and transduction of high rate deformation. This model system may be further exploited for the elucidation of mechanotransduction mechanisms and cellular pathology following mechanical insult.
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Affiliation(s)
- D Kacy Cullen
- GT/Emory Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Dr., Atlanta, GA 30332-0535, USA
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337
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Toh YC, Zhang C, Zhang J, Khong YM, Chang S, Samper VD, van Noort D, Hutmacher DW, Yu H. A novel 3D mammalian cell perfusion-culture system in microfluidic channels. LAB ON A CHIP 2007; 7:302-9. [PMID: 17330160 DOI: 10.1039/b614872g] [Citation(s) in RCA: 284] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Mammalian cells cultured on 2D surfaces in microfluidic channels are increasingly used in drug development and biological research applications. These systems would have more biological or clinical relevance if the cells exhibit 3D phenotypes similar to the cells in vivo. We have developed a microfluidic channel based system that allows cells to be perfusion-cultured in 3D by supporting them with adequate 3D cell-cell and cell-matrix interactions. The maximal cell-cell interaction was achieved by perfusion-seeding cells through an array of micropillars; and 3D cell-matrix interactions were achieved by a polyelectrolyte complex coacervation process to form a thin layer of matrix conforming to the 3D cell shapes. Carcinoma cell lines (HepG2, MCF7), primary differentiated (hepatocytes) and primary progenitor cells (bone marrow mesenchymal stem cells) were perfusion-cultured for 72 hours to 1 week in the microfluidic channel, which preserved their 3D cyto-architecture and cell-specific functions or differentiation competence. This transparent 3D microfluidic channel-based cell culture system also allows direct optical monitoring of cellular events for a wide range of applications.
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Affiliation(s)
- Yi-Chin Toh
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos, 138669, Singapore
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338
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Grzesiak JJ, Bouvet M. Determination of the ligand-binding specificities of the alpha2beta1 and alpha1beta1 integrins in a novel 3-dimensional in vitro model of pancreatic cancer. Pancreas 2007; 34:220-8. [PMID: 17312461 DOI: 10.1097/01.mpa.0000250129.64650.f6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Pancreatic cancer cells express 2 known collagen-binding integrins, alpha2beta1 and alpha1beta1. The ligand-binding specificity of alpha1beta1 and the integrin/s responsible for mediating the malignant phenotype on type I collagen in the 3-dimensional (3D) tumor microenvironment have not been determined in pancreatic cancer. The aim of the present study was to determine the ligand-binding specificities of the alpha2beta1 and alpha1beta1 integrins using a novel 3D in vitro model of pancreatic cancer. METHODS We used 3D type I collagen-glycosaminoglycan scaffolds in adhesion and proliferation assays with pancreatic cancer cell lines, as well as affinity chromatography and inhibition of adhesion assays. RESULTS We demonstrate for the first time that CFPAC, BxPC-3, Colo-357, FG, and Panc-1 cells attach to 3D type I collagen scaffolds in an alpha2beta1-specific manner and that this integrin-specific adhesion is required for subsequent cell proliferation. MiaPaCa-2 cells, which do not express the alpha2beta1 or alpha1beta1 integrins, do not attach or proliferate on 3D type I collagen scaffolds. We also demonstrate the novel finding that the alpha1beta1 integrin is a type IV collagen receptor in pancreatic cancer cells. CONCLUSIONS These data indicate that targeting alpha2beta1 integrin-specific type I collagen adhesion may have therapeutic value in the treatment of pancreatic cancer.
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Affiliation(s)
- John J Grzesiak
- Department of Surgery, University of California San Diego, San Diego, CA, USA
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339
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Ensslin MA, Shur BD. The EGF repeat and discoidin domain protein, SED1/MFG-E8, is required for mammary gland branching morphogenesis. Proc Natl Acad Sci U S A 2007; 104:2715-20. [PMID: 17299048 PMCID: PMC1815247 DOI: 10.1073/pnas.0610296104] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SED1, also known as MFG-E8, is a secreted protein composed of two EGF repeats (the second of which contains an RGD motif) and two discoidin/Factor V/VIII C domains. SED1 is expressed by a wide range of cell types, where it participates in diverse cellular interactions, such as sperm binding to the egg coat and macrophage recognition of apoptotic lymphocytes. Although SED1 was originally identified as a milk protein, its function in the mammary gland remains unclear; suggested functions include inhibition of viral infection and clearance of apoptotic cells during mammary gland involution. We report here that SED1 has an unexpected obligatory role during mammary gland development. Unlike that seen in WT glands, SED1-null glands show severely reduced branching from epithelial ducts and from terminal end buds, which are thin and poorly developed. SED1 is expressed by both luminal and myoepithelial cells in the developing epithelial duct, and binds to alpha(v) integrin receptors on myoepithelial cells leading to MAPK activation and cell proliferation. The absence of SED1 leads to greatly reduced levels of activated MAPK and a concomitant reduction in cell proliferation and branching throughout the epithelial tree. These results suggest that SED1 contributes, at least partly, to the intercellular signaling between luminal and myoepithelial cells that is required for branching morphogenesis.
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Affiliation(s)
- Michael A. Ensslin
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | - Barry D. Shur
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
- *To whom correspondence should be addressed. E-mail:
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340
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Ahmed I, Ponery AS, Nur-E-Kamal A, Kamal J, Meshel AS, Sheetz MP, Schindler M, Meiners S. Morphology, cytoskeletal organization, and myosin dynamics of mouse embryonic fibroblasts cultured on nanofibrillar surfaces. Mol Cell Biochem 2007; 301:241-9. [PMID: 17294137 DOI: 10.1007/s11010-007-9417-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Accepted: 01/19/2007] [Indexed: 01/16/2023]
Abstract
Growth of cells in tissue culture is generally performed on two-dimensional (2D) surfaces composed of polystyrene or glass. Recent work, however, has shown that such 2D cultures are incomplete and do not adequately represent the physical characteristics of native extracellular matrix (ECM)/basement membrane (BM), namely dimensionality, compliance, fibrillarity, and porosity. In the current study, a three-dimensional (3D) nanofibrillar surface composed of electrospun polyamide nanofibers was utilized to mimic the topology and physical structure of ECM/BM. Additional chemical cues were incorporated into the nanofibrillar matrix by coating the surfaces with fibronectin, collagen I, or laminin-1. Results from the current study show an enhanced response of primary mouse embryonic fibroblasts (MEFs) to culture on nanofibrillar surfaces with more dramatic changes in cell spreading and reorganization of the cytoskeleton than previously observed for established cell lines. In addition, the cells cultured on nanofibrillar and 2D surfaces exhibited differential responses to the specific ECM/BM coatings. The localization and activity of myosin II-B for MEFs cultured on nanofibers was also compared. A dynamic redistribution of myosin II-B was observed within membrane protrusions. This was previously described for cells associated with nanofibers composed of collagen I but not for cells attached to 2D surfaces coated with monomeric collagen. These results provide further evidence that nanofibrillar surfaces offer a significantly different environment for cells than 2D substrates.
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Affiliation(s)
- Ijaz Ahmed
- Department of Pharmacology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
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341
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Chin AC, Parkos CA. Pathobiology of Neutrophil Transepithelial Migration: Implications in Mediating Epithelial Injury. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2007; 2:111-43. [DOI: 10.1146/annurev.pathol.2.010506.091944] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Alex C. Chin
- Epithelial Pathobiology Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia 30322; ,
| | - Charles A. Parkos
- Epithelial Pathobiology Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia 30322; ,
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342
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Bokhari M, Carnachan RJ, Cameron NR, Przyborski SA. Novel cell culture device enabling three-dimensional cell growth and improved cell function. Biochem Biophys Res Commun 2007; 354:1095-100. [PMID: 17276400 DOI: 10.1016/j.bbrc.2007.01.105] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 01/20/2007] [Indexed: 11/24/2022]
Abstract
A better understanding of cell biology and cell-cell interactions requires three-dimensional (3-D) culture systems that more closely represent the natural structure and function of tissues in vivo. Here, we present a novel device that provides an environment for routine 3-D cell growth in vitro. We have developed a thin membrane of polystyrene scaffold with a well defined and uniform porous architecture and have adapted this material for cell culture applications. We have exemplified the application of this technology by growing HepG2 liver cells on 2- and 3-D substrates. The performance of HepG2 cells grown on scaffolds was significantly enhanced compared to functional activity of cells grown on 2-D plastic. The incorporation of thin membranes of porous polystyrene to create a novel device has been successfully demonstrated as a new 3-D cell growth technology for routine use in cell culture.
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Affiliation(s)
- Maria Bokhari
- School of Biological and Biomedical Science, Durham University, South Road, Durham, UK
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343
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Morais Freitas V, Nogueira da Gama de Souza L, Cyreno Oliveira E, Furuse C, Cavalcanti de Araújo V, Gastaldoni Jaeger R. Malignancy-related 67kDa laminin receptor in adenoid cystic carcinoma. Effect on migration and beta-catenin expression. Oral Oncol 2007; 43:987-98. [PMID: 17257887 DOI: 10.1016/j.oraloncology.2006.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 11/07/2006] [Accepted: 11/08/2006] [Indexed: 10/23/2022]
Abstract
Adenoid cystic carcinoma is a malignant salivary gland neoplasm with recurrence and metastasis. We studied the expression of a malignancy-related non-integrin laminin receptor, the 67LR, in this neoplasm. Immunohistochemistry showed 67LR in adenoid cystic carcinoma. This receptor binds a sequence of laminin beta1 chain, the YIGSR peptide. We studied the effect of 67LR and YIGSR in cells (CAC2) from adenoid cystic carcinoma. Three-dimensional cultures of cells embedded into either laminin-111 gel (controls) or YIGSR-enriched laminin-111 (treated) were prepared and studied by light microscopy. CAC2 cells treated with YIGSR appeared fibroblast-like, while control cells were epithelioid. Blockage of 67LR by antibody abolished YIGSR effect in three-dimensional cultures. We analysed the relevance of 67LR and YIGSR on beta-catenin expression in CAC2 cells. Immunofluorescence and immunoblot showed that YIGSR decreased beta-catenin, while blockage of 67LR restored the presence of this molecule. The 67LR and YIGSR induced fibroblast-like morphology in CAC2 cells, with disruption of cell-cell contacts and decrease of beta-catenin. These features resemble epithelial-mesenchymal transition (EMT). EMT also increases cell migration. In monolayer assays YIGSR increased migration of CAC2 cells. We conclude that 67LR and YIGSR are involved in epithelial-mesenchymal transition, modulation of beta-catenin expression, and migratory activity of CAC2 cells.
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Affiliation(s)
- Vanessa Morais Freitas
- Department of Cellular and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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344
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Bokhari M, Carnachan RJ, Przyborski SA, Cameron NR. Emulsion-templated porous polymers as scaffolds for three dimensional cell culture: effect of synthesis parameters on scaffold formation and homogeneity. ACTA ACUST UNITED AC 2007. [DOI: 10.1039/b707499a] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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345
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Affiliation(s)
- Michael W Hess
- Division of Histology and Embryology, Innsbruck Medical University, A-6020 Innsbruck, Austria
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346
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Kang X, Xie Y, Powell HM, James Lee L, Belury MA, Lannutti JJ, Kniss DA. Adipogenesis of murine embryonic stem cells in a three-dimensional culture system using electrospun polymer scaffolds. Biomaterials 2007; 28:450-8. [PMID: 16997371 DOI: 10.1016/j.biomaterials.2006.08.052] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 08/25/2006] [Indexed: 11/30/2022]
Abstract
A mechanistic understanding of adipose tissue differentiation is critical for the treatment and prevention of obesity and type 2 diabetes. Conventional in vitro models of adipogenesis are preadipocytes or freshly isolated adipocytes grown in two-dimensional (2D) cultures. Optimal results using in vitro tissue culture models can be expected only when adipocyte models closely resemble adipose tissue in vivo. Thus the design of an in vitro three-dimensional (3D) model which faithfully mimics the in vivo environment is needed to effectively study adipogenesis. Pluripotent embryonic stem (ES) cells are a self-renewing cell type that can readily be differentiated into adipocytes. In this study, a 3D culture system was developed to mimic the geometry of adipose tissue in vivo. Murine ES cells were seeded into electrospun polycaprolactone scaffolds and differentiated into adipocytes in situ by hormone induction as demonstrated using a battery of gene and protein expression markers along with the accumulation of neutral lipid droplets. Insulin-responsive Akt phosphorylation, and beta-adrenergic stimulation of cyclic AMP synthesis were demonstrated in ES cell-derived adipocytes. Morphologically, ES cell-derived adipocytes resembled native fat cells by scanning electron and phase contrast microscopy. This tissue engineered ES cell-matrix model has potential uses in drug screening and other therapeutic developments.
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Affiliation(s)
- Xihai Kang
- Department of Obstetrics and Gynecology (Laboratory of Perinatal Research), The Ohio State University, College of Medicine, 1654 Upham Drive, Means Hall, Fifth Floor, Columbus, OH 43210, USA
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347
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Mochizuki M, Yamagata N, Philp D, Hozumi K, Watanabe T, Kikkawa Y, Kadoya Y, Kleinman HK, Nomizu M. Integrin-dependent cell behavior on ECM peptide-conjugated chitosan membranes. Biopolymers 2007; 88:122-30. [PMID: 17236208 DOI: 10.1002/bip.20684] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Extracellular matrix (ECM) plays an important role in tissue regeneration by promoting cell adhesion, migration, proliferation, and differentiation. ECM mimetics are of importance for tissue engineering because of their functions as scaffolds for cells. Previously, we developed bioactive laminin-derived peptide-conjugated chitosan membranes and demonstrated their cell- and peptide-type specific functions. Here, we conjugated twelve integrin-binding peptides derived from ECM proteins onto chitosan membranes and examined biological activity. Seven peptide-chitosan membranes promoted human foreskin fibroblast attachment. Additionally, FIB1 (YAVTGRGDSPAS; from fibronectin), A99 (AGTFALRGDNPQG; from laminin alpha1 chain), EF1zz (ATLQLQEGRLHFXFDLGKGR, X = Nle; from laminin alpha1 chain), and 531 (GEFYFDLRLKGDKY; from collagen alpha1 (IV) chain) conjugated chitosan membranes promoted integrin-dependent cell adhesion. Various integrins, including alphav, beta1, and beta3, were involved in the cell adhesion to the peptide-chitosan membranes. Further, only the FIB1- and A99-chitosan membranes promoted neurite outgrowth with PC12 rat pheochromocytoma cells. These data demonstrate that peptide-chitosan membranes can regulate specific integrin-mediated cell responses and are useful constructs as ECM mimetics.
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Affiliation(s)
- Mayumi Mochizuki
- Laboratory of Clinical Biochemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
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348
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Gelain F, Bottai D, Vescovi A, Zhang S. Designer self-assembling peptide nanofiber scaffolds for adult mouse neural stem cell 3-dimensional cultures. PLoS One 2006; 1:e119. [PMID: 17205123 PMCID: PMC1762423 DOI: 10.1371/journal.pone.0000119] [Citation(s) in RCA: 405] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Accepted: 11/27/2006] [Indexed: 12/02/2022] Open
Abstract
Biomedical researchers have become increasingly aware of the limitations of conventional 2-dimensional tissue cell culture systems, including coated Petri dishes, multi-well plates and slides, to fully address many critical issues in cell biology, cancer biology and neurobiology, such as the 3-D microenvironment, 3-D gradient diffusion, 3-D cell migration and 3-D cell-cell contact interactions. In order to fully understand how cells behave in the 3-D body, it is important to develop a well-controlled 3-D cell culture system where every single ingredient is known. Here we report the development of a 3-D cell culture system using a designer peptide nanofiber scaffold with mouse adult neural stem cells. We attached several functional motifs, including cell adhesion, differentiation and bone marrow homing motifs, to a self-assembling peptide RADA16 (Ac-RADARADARADARADA-COHN2). These functionalized peptides undergo self-assembly into a nanofiber structure similar to Matrigel. During cell culture, the cells were fully embedded in the 3-D environment of the scaffold. Two of the peptide scaffolds containing bone marrow homing motifs significantly enhanced the neural cell survival without extra soluble growth and neurotrophic factors to the routine cell culture media. In these designer scaffolds, the cell populations with β-Tubulin+, GFAP+ and Nestin+ markers are similar to those found in cell populations cultured on Matrigel. The gene expression profiling array experiments showed selective gene expression, possibly involved in neural stem cell adhesion and differentiation. Because the synthetic peptides are intrinsically pure and a number of desired function cellular motifs are easy to incorporate, these designer peptide nanofiber scaffolds provide a promising controlled 3-D culture system for diverse tissue cells, and are useful as well for general molecular and cell biology.
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Affiliation(s)
- Fabrizio Gelain
- Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Stem Cell Research Institute, Department of Biological and Technological Research, Fondazione Centro San Raffaele del Monte Tabor, Milan, Italy
- Bioscience and Biotechnology Department, University of Milan-Bicocca, Milan, Italy
| | - Daniele Bottai
- Stem Cell Research Institute, Department of Biological and Technological Research, Fondazione Centro San Raffaele del Monte Tabor, Milan, Italy
- Department of Medicine, Surgery and Dentistry, Faculty of Medicine, University of Milan, Milan, Italy
| | - Angleo Vescovi
- Stem Cell Research Institute, Department of Biological and Technological Research, Fondazione Centro San Raffaele del Monte Tabor, Milan, Italy
- Bioscience and Biotechnology Department, University of Milan-Bicocca, Milan, Italy
| | - Shuguang Zhang
- Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * To whom correspondence should be addressed. E-mail:
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349
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Pelham RJ, Rodgers L, Hall I, Lucito R, Nguyen KCQ, Navin N, Hicks J, Mu D, Powers S, Wigler M, Botstein D. Identification of alterations in DNA copy number in host stromal cells during tumor progression. Proc Natl Acad Sci U S A 2006; 103:19848-53. [PMID: 17167050 PMCID: PMC1698871 DOI: 10.1073/pnas.0609635104] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The interactions between cancer cells and the surrounding host stromal tissue play a critical role in tumor progression and metastasis, but the molecular nature of this relationship remains largely uncharacterized. Furthermore, although genetic changes of neoplastic cells in tumors contribute significantly to tumor progression, it is not known whether similar changes occur in the adjacent host stromal microenvironment and whether they contribute to or inhibit tumorigenesis. To address this question in an unbiased and genome-wide manner, we applied high-resolution DNA copy number analysis to murine stromal DNA isolated from human xenograft tumors that were formed in immunodeficient mice. We show that numerous amplifications and deletions are found within the host stromal microenvironment, suggesting that alterations in host DNA copy number can occur and may play a significant role in modifying tumor-stromal interactions.
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Affiliation(s)
- Robert J. Pelham
- *Lewis–Sigler Institute for Integrative Genomics and
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544; and
- To whom correspondence may be addressed. E-mail:
or
| | - Linda Rodgers
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - Ira Hall
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - Robert Lucito
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - Ken C. Q. Nguyen
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - Nicholas Navin
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - James Hicks
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - David Mu
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - Scott Powers
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - Michael Wigler
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724
| | - David Botstein
- *Lewis–Sigler Institute for Integrative Genomics and
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544; and
- To whom correspondence may be addressed. E-mail:
or
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350
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Khaitan D, Dwarakanath BS. Multicellular spheroids as anin vitromodel in experimental oncology: applications in translational medicine. Expert Opin Drug Discov 2006; 1:663-75. [DOI: 10.1517/17460441.1.7.663] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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