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Chen Y, Val S, Krueger A, Zhong L, Panigrahi A, Nino G, Wolf S, Preciado D. Human primary middle ear epithelial cell culture: A novel in vitro model to study otitis media. Laryngoscope Investig Otolaryngol 2019; 4:663-672. [PMID: 31890886 PMCID: PMC6929573 DOI: 10.1002/lio2.319] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/29/2019] [Accepted: 09/23/2019] [Indexed: 12/21/2022] Open
Abstract
Objectives Otitis media (OM) is a ubiquitous pediatric disease leading to a significant health care burden. There is no medication beneficial to resolving COM fluid, highlighting the need for research in the field. Crucially, current human middle ear epithelial cell models are transformed cells not recapitulating physiological functions. Herein, we describe a new method to proliferate and differentiate pediatric primary middle ear epithelial cells (pMEEC) from patients as a physiological model for the study of OM. Methods We adapted a cell reprogramming protocol using irradiated fibroblast feeder medium in addition to Rho kinase inhibitor to proliferate pMEEC collected during cochlear implant surgery. Cells were plated on transwell membranes, proliferated with conditionally reprogrammed culture medium, and transferred to air–liquid interface (ALI). Cultures were maintained for 4 weeks at ALI, photos were taken and cell lysates and secretions were collected over time for characterization analysis using quantitative polymerase chain reaction, Western bolt, and proteomics. Keratins, MUC5B and MUC5AC mucins, and beta tubulin (TUBB) were analyzed at the mRNA and protein level. Results Cultures took a mean of 2 weeks to proliferate before transwell plating and forming a tight epithelium at ALI from 2 to 4 weeks. Although mRNA expression of MUC5B, MUC5AC, TUBB, and keratin 5 (KRT5) were variable depending on the differentiation stage and the patient, both TUBB and KRT5 proteins were detected until week 2. Conclusion We demonstrate a novel method to proliferate and differentiate pMEECs that express epithelial markers and that are able to secrete mucins for the study of OM. Level of Evidence NA
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Affiliation(s)
- Yajun Chen
- Sheikh Zayed Center for Pediatric Surgical Innovation and Division of Otolaryngology Children's National Health System Washington District of Columbia U.S.A
| | - Stéphanie Val
- Sheikh Zayed Center for Pediatric Surgical Innovation and Division of Otolaryngology Children's National Health System Washington District of Columbia U.S.A
| | - Anna Krueger
- Sheikh Zayed Center for Pediatric Surgical Innovation and Division of Otolaryngology Children's National Health System Washington District of Columbia U.S.A
| | - Lydia Zhong
- Sheikh Zayed Center for Pediatric Surgical Innovation and Division of Otolaryngology Children's National Health System Washington District of Columbia U.S.A
| | - Aswini Panigrahi
- Center for Cancer and Immunology Research Children's National Health System Washington District of Columbia U.S.A
| | - Gustavo Nino
- Division of Pulmonary Medicine Children's National Health System Washington District of Columbia U.S.A
| | - Seth Wolf
- Division of Pulmonary Medicine Children's National Health System Washington District of Columbia U.S.A
| | - Diego Preciado
- Sheikh Zayed Center for Pediatric Surgical Innovation and Division of Otolaryngology Children's National Health System Washington District of Columbia U.S.A.,Division of Pediatric Otolaryngology Children's National Health System Washington District of Columbia U.S.A
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Khorraminejad-Shirazi M, Dorvash M, Estedlal A, Hoveidaei AH, Mazloomrezaei M, Mosaddeghi P. Aging: A cell source limiting factor in tissue engineering. World J Stem Cells 2019; 11:787-802. [PMID: 31692986 PMCID: PMC6828594 DOI: 10.4252/wjsc.v11.i10.787] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/03/2019] [Accepted: 09/05/2019] [Indexed: 02/06/2023] Open
Abstract
Tissue engineering has yet to reach its ideal goal, i.e. creating profitable off-the-shelf tissues and organs, designing scaffolds and three-dimensional tissue architectures that can maintain the blood supply, proper biomaterial selection, and identifying the most efficient cell source for use in cell therapy and tissue engineering. These are still the major challenges in this field. Regarding the identification of the most appropriate cell source, aging as a factor that affects both somatic and stem cells and limits their function and applications is a preventable and, at least to some extents, a reversible phenomenon. Here, we reviewed different stem cell types, namely embryonic stem cells, adult stem cells, induced pluripotent stem cells, and genetically modified stem cells, as well as their sources, i.e. autologous, allogeneic, and xenogeneic sources. Afterward, we approached aging by discussing the functional decline of aged stem cells and different intrinsic and extrinsic factors that are involved in stem cell aging including replicative senescence and Hayflick limit, autophagy, epigenetic changes, miRNAs, mTOR and AMPK pathways, and the role of mitochondria in stem cell senescence. Finally, various interventions for rejuvenation and geroprotection of stem cells are discussed. These interventions can be applied in cell therapy and tissue engineering methods to conquer aging as a limiting factor, both in original cell source and in the in vitro proliferated cells.
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Affiliation(s)
- Mohammadhossein Khorraminejad-Shirazi
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Cell and Molecular Medicine Student Research Group, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Mohammadreza Dorvash
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Cell and Molecular Medicine Student Research Group, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz 7134814336, Iran
| | - Alireza Estedlal
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Cell and Molecular Medicine Student Research Group, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Amir Human Hoveidaei
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Mohsen Mazloomrezaei
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Cell and Molecular Medicine Student Research Group, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Pouria Mosaddeghi
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Cell and Molecular Medicine Student Research Group, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz 7134814336, Iran
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Mondal AM, Ma AH, Li G, Krawczyk E, Yuan R, Lu J, Schlegel R, Stamatakis L, Kowalczyk KJ, Philips GK, Pan CX, Liu X. Fidelity of a PDX-CR model for bladder cancer. Biochem Biophys Res Commun 2019; 517:49-56. [PMID: 31303270 DOI: 10.1016/j.bbrc.2019.06.165] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 06/30/2019] [Indexed: 01/14/2023]
Abstract
Patient-derived xenografts (PDXs) are widely recognised as a more physiologically relevant preclinical model than standard cell lines, but are expensive and low throughput, have low engraftment rate and take a long time to develop. Our newly developed conditional reprogramming (CR) technology addresses many PDX drawbacks, but lacks many in vivo factors. Here we determined whether PDXs and CRCs of the same cancer origin maintain the biological fidelity and complement each for translational research and drug development. Four CRC lines were generated from bladder cancer PDXs. Short tandem repeat (STR) analyses revealed that CRCs and their corresponding parental PDXs shared the same STRs, suggesting common cancer origins. CRCs and their corresponding parental PDXs contained the same genetic alterations. Importantly, CRCs retained the same drug sensitivity with the corresponding downstream signalling activity as their corresponding parental PDXs. This suggests that CRCs and PDXs can complement each other, and that CRCs can be used for in vitro fast, high throughput and low cost screening while PDXs can be used for in vivo validation and study of the in vivo factors during translational research and drug development.
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Affiliation(s)
- Abdul M Mondal
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Washington DC, USA
| | - Ai-Hong Ma
- Division of Hematology and Oncology, Department of Internal Medicine, School of Medicine, University of California Davis, Washington DC, USA
| | - Guangzhao Li
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Washington DC, USA
| | - Ewa Krawczyk
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Washington DC, USA
| | - Ruan Yuan
- Division of Hematology and Oncology, Department of Internal Medicine, School of Medicine, University of California Davis, Washington DC, USA; Department of Urology, Renmin Hospital, Wuhan University, Washington DC, USA
| | - Jie Lu
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Washington DC, USA
| | - Richard Schlegel
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Washington DC, USA
| | - Lambros Stamatakis
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA; Department of Urology, MedStar Washington Hospital Center, Washington DC, USA
| | - Keith J Kowalczyk
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA; Department of Urology, MedStar Georgetown Hospital, Washington DC, USA
| | - George K Philips
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA; Department of Oncology, MedStar Georgetown Hospital, Washington DC, USA
| | - Chong-Xian Pan
- Division of Hematology and Oncology, Department of Internal Medicine, School of Medicine, University of California Davis, Washington DC, USA; VA Northern California Health Care System, Mather, CA, USA.
| | - Xuefeng Liu
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Washington DC, USA; Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA.
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Kolb AD, Shupp AB, Mukhopadhyay D, Marini FC, Bussard KM. Osteoblasts are "educated" by crosstalk with metastatic breast cancer cells in the bone tumor microenvironment. Breast Cancer Res 2019; 21:31. [PMID: 30813947 PMCID: PMC6391840 DOI: 10.1186/s13058-019-1117-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/07/2019] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION In a cancer-free environment in the adult, the skeleton continuously undergoes remodeling. Bone-resorbing osteoclasts excavate erosion cavities, and bone-depositing osteoblasts synthesize osteoid matrix that forms new bone, with no net bone gain or loss. When metastatic breast cancer cells invade the bone, this balance is disrupted. Patients with bone metastatic breast cancer frequently suffer from osteolytic bone lesions that elicit severe bone pain and fractures. Bisphosphonate treatments are not curative. Under ideal circumstances, osteoblasts would synthesize new matrix to fill in erosion cavities caused by osteoclasts, but this is not what occurs. Our prior evidence demonstrated that osteoblasts are diverted from laying down bone matrix to producing cytokines that facilitate breast cancer cell maintenance in late-stage disease. Here, we have new evidence to suggest that there are subpopulations of osteoblasts in the tumor niche as evidenced by their protein marker expression that have distinct roles in tumor progression in the bone. METHODS Tumor-bearing tibia of mice was interrogated by immunofluorescent staining for the presence of osteoblasts and alterations in niche protein expression. De-identified tissue from patients with bone metastatic breast cancer was analyzed for osteoblast subpopulations via multi-plex immunofluorescent staining. Effects of breast cancer cells on osteoblasts were recapitulated in vitro by osteoblast exposure to breast cancer-conditioned medium. Triple-negative and estrogen receptor-positive breast cancer proliferation, cell cycle, and p21 expression were assessed upon contact with "educated" osteoblasts. RESULTS A subpopulation of osteoblasts was identified in the bone tumor microenvironment in vivo of both humans and mice with bone metastatic breast cancer that express RUNX2/OCN/OPN but is negative for IL-6 and alpha-smooth muscle actin. These tumor "educated" osteoblasts (EOs) have altered properties compared to "uneducated" osteoblasts and suppress both triple-negative and estrogen receptor-positive breast cancer cell proliferation and increase cancer cell p21 expression. EO effects on breast cancer proliferation were mediated by NOV and decorin. Importantly, the presence of EO cells in the tibia of mice bearing tumors led to increased amounts of alkaline phosphatase and suppressed the expression of inflammatory cytokines in vivo. CONCLUSIONS Our work reveals that there is a subpopulation of osteoblasts in the bone tumor microenvironment that demonstrate a functional role in retarding breast cancer cell growth.
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Affiliation(s)
- Alexus D. Kolb
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA USA
| | - Alison B. Shupp
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA USA
| | - Dimpi Mukhopadhyay
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA USA
| | - Frank C. Marini
- Comprehensive Cancer Center Wake Forest University and Wake Forest Institute of Regenerative Medicine, Winston-Salem, NC USA
| | - Karen M. Bussard
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA USA
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Mondal AM, Zhou H, Horikawa I, Suprynowicz FA, Li G, Dakic A, Rosenthal B, Ye L, Harris CC, Schlegel R, Liu X. Δ133p53α, a natural p53 isoform, contributes to conditional reprogramming and long-term proliferation of primary epithelial cells. Cell Death Dis 2018; 9:750. [PMID: 29970881 PMCID: PMC6030220 DOI: 10.1038/s41419-018-0767-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/25/2018] [Accepted: 06/08/2018] [Indexed: 12/12/2022]
Abstract
We previously developed the technique of conditional reprogramming (CR), which allows primary epithelial cells from fresh or cryopreserved specimens to be propagated long-term in vitro, while maintaining their genetic stability and differentiation potential. This method requires a combination of irradiated fibroblast feeder cells and a Rho-associated kinase (ROCK) inhibitor. In the present study, we demonstrate increased levels of full-length p53 and its natural isoform, Δ133p53α, in conditionally reprogrammed epithelial cells from primary prostate, foreskin, ectocervical, and mammary tissues. Increased Δ133p53α expression is critical for CR since cell proliferation is rapidly inhibited following siRNA knockdown of endogenous Δ133p53α. Importantly, overexpression of Δ133p53α consistently delays the onset of cellular senescence of primary cells when cultured under non-CR conditions in normal keratinocyte growth medium (KGM). More significantly, the combination of Δ133p53α overexpression and ROCK inhibitor, without feeder cells, enables primary epithelial cells to be propagated long-term in vitro. We also show that Δ133p53α overexpression induces hTERT expression and telomerase activity and that siRNA knockdown of hTERT causes rapid inhibition of cell proliferation, indicating a critical role of hTERT for mediating the effects of Δ133p53α. Altogether, these data demonstrate a functional and regulatory link between p53 pathways and hTERT expression during the conditional reprogramming of primary epithelial cells.
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Affiliation(s)
- Abdul M Mondal
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA
| | - Hua Zhou
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA.,Guizhou Medical University, Guiyang, Guizhou, China
| | - Izumi Horikawa
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Frank A Suprynowicz
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA
| | - Guangzhao Li
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA
| | - Aleksandra Dakic
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA
| | - Bernard Rosenthal
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA
| | - Lin Ye
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA.,Shenzhen Eye Hospital, Shenzhen, Guangdong, China
| | - Curtis C Harris
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard Schlegel
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA.
| | - Xuefeng Liu
- Center for Cell Reprograming, Department of Pathology, Georgetown University Medical Center, Georgrtown, WA, 20057, USA. .,Second Xianya Hospital (Adjunct Position), Zhongnan University, Changsha, Huna, China. .,Affiliated Cancer Hospital & Institute (Adjunct Position), Guangzhou Medical University, Guangzhou, Guangdong, China.
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Bana E, Sibille E, Valente S, Cerella C, Chaimbault P, Kirsch G, Dicato M, Diederich M, Bagrel D. A novel coumarin-quinone derivative SV37 inhibits CDC25 phosphatases, impairs proliferation, and induces cell death. Mol Carcinog 2013; 54:229-41. [PMID: 24155226 DOI: 10.1002/mc.22094] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 09/16/2013] [Accepted: 09/24/2013] [Indexed: 11/11/2022]
Abstract
Cell division cycle (CDC) 25 proteins are key phosphatases regulating cell cycle transition and proliferation by regulating CDK/cyclin complexes. Overexpression of these enzymes is frequently observed in cancer and is related to aggressiveness, high-grade tumors and poor prognosis. Thus, targeting CDC25 by compounds, able to inhibit their activity, appears a good therapeutic approach. Here, we describe the synthesis of a new inhibitor (SV37) whose structure is based on both coumarin and quinone moieties. An analytical in vitro approach shows that this compound efficiently inhibits all three purified human CDC25 isoforms (IC50 1-9 µM) in a mixed-type mode. Moreover, SV37 inhibits growth of breast cancer cell lines. In MDA-MB-231 cells, reactive oxygen species generation is followed by pCDK accumulation, a mark of CDC25 dysfunction. Eventually, SV37 treatment leads to activation of apoptosis and DNA cleavage, underlining the potential of this new type of coumarin-quinone structure.
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Affiliation(s)
- Emilie Bana
- Laboratoire "Structure et Réactivité des Systèmes Moléculaires Complexes, UMR CNRS 7565, Université de Lorraine, Campus Bridoux, Rue du Général Delestraint, Metz, France; Laboratoire de Biologie Moléculaire et Cellulaire du Cancer, Fondation de Recherche Cancer et Sang, Hôpital Kirchberg, Luxembourg, Luxembourg
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Liu X, Ory V, Chapman S, Yuan H, Albanese C, Kallakury B, Timofeeva OA, Nealon C, Dakic A, Simic V, Haddad BR, Rhim JS, Dritschilo A, Riegel A, McBride A, Schlegel R. ROCK inhibitor and feeder cells induce the conditional reprogramming of epithelial cells. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 180:599-607. [PMID: 22189618 DOI: 10.1016/j.ajpath.2011.10.036] [Citation(s) in RCA: 566] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 10/06/2011] [Accepted: 10/11/2011] [Indexed: 12/20/2022]
Abstract
We demonstrate that a Rho kinase inhibitor (Y-27632), in combination with fibroblast feeder cells, induces normal and tumor epithelial cells from many tissues to proliferate indefinitely in vitro, without transduction of exogenous viral or cellular genes. Primary prostate and mammary cells, for example, are reprogrammed toward a basaloid, stem-like phenotype and form well-organized prostaspheres and mammospheres in Matrigel. However, in contrast to the selection of rare stem-like cells, the described growth conditions can generate 2 × 10(6) cells in 5 to 6 days from needle biopsies, and can generate cultures from cryopreserved tissue and from fewer than four viable cells. Continued cell proliferation is dependent on both feeder cells and Y-27632, and the conditionally reprogrammed cells (CRCs) retain a normal karyotype and remain nontumorigenic. This technique also efficiently establishes cell cultures from human and rodent tumors. For example, CRCs established from human prostate adenocarcinoma displayed instability of chromosome 13, proliferated abnormally in Matrigel, and formed tumors in mice with severe combined immunodeficiency. The ability to rapidly generate many tumor cells from small biopsy specimens and frozen tissue provides significant opportunities for cell-based diagnostics and therapeutics (including chemosensitivity testing) and greatly expands the value of biobanking. In addition, the CRC method allows for the genetic manipulation of epithelial cells ex vivo and their subsequent evaluation in vivo in the same host.
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Affiliation(s)
- Xuefeng Liu
- Department of Pathology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School, Washington, DC 20057, USA
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Lindsay J, McDade SS, Pickard A, McCloskey KD, McCance DJ. Role of DeltaNp63gamma in epithelial to mesenchymal transition. J Biol Chem 2010; 286:3915-24. [PMID: 21127042 DOI: 10.1074/jbc.m110.162511] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although members of the p63 family of transcription factors are known for their role in the development and differentiation of epithelial surfaces, their function in cancer is less clear. Here, we show that depletion of the ΔNp63α and β isoforms, leaving only ΔNp63γ, results in epithelial to mesenchymal transition (EMT) in the normal breast cell line MCF10A. EMT can be rescued by the expression of the ΔNp63α isoform. We also show that ΔNp63γ expressed in a background where all the other ΔNp63 are knocked down causes EMT with an increase in TGFβ-1, -2, and -3 and downstream effectors Smads2/3/4. In addition, a p63 binding site in intron 1 of TGFβ was identified. Inhibition of the TGFβ response with a specific inhibitor results in reversion of EMT in ΔNp63α- and β-depleted cells. In summary, we show that p63 is involved in inhibiting EMT and reduction of certain p63 isoforms may be important in the development of epithelial cancers.
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Affiliation(s)
- Jaime Lindsay
- Centre for Cancer Research and Cell Biology, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom
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Wen F, Ellingson SM, Kyogoku C, Peterson EJ, Gaffney PM. Exon 6 variants carried on systemic lupus erythematosus (SLE) risk haplotypes modulate IRF5 function. Autoimmunity 2010; 44:82-9. [PMID: 20695768 DOI: 10.3109/08916934.2010.491842] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Interferon regulatory factor 5 (IRF5) regulates innate immune responses to viral infection. IRF5 genetic variants have been shown to be strongly associated with risk for systemic lupus erythematosus (SLE). Functional roles of IRF5 exon 6 structural variants that occur as part of a SLE risk-associated haplotype, including a 30-bp in/del (in/del-10) and a 48-bp splice-site variant (SV-16), have not been established. In this study, we used IRF5-deficient cells overexpressing human IRF5 (hIRF5) variants to investigate the roles of exon 6 in/del-10 and SV-16 in regulation of the apoptosis response, nuclear translocation, and ability to transactivate IRF5 responsive cytokines. We found that expression of IRF5 isoforms including either SV-16 or in/del-10 confers ability of IRF5 to impair the apoptotic response and correlates with reduced capacity for IRF5 nuclear translocation in MEFs after a DNA-damaging stimulus treatment. Interestingly, the presence or absence of both SV-16 and in/del-10 results in abrogation of both the anti-apoptotic and enhanced nuclear translocation effects of IRF5 expression. Only cells expressing IRF5 bearing SV-16 show increased IL-6 production upon lipopolysaccharide stimulation. MEFs expressing hIRF5 variants containing in/del-10 showed no significant difference from the control; however, cells carrying hIRF5 lacking both SV-16 and in/del-10 showed reduced IL-6 production. Our overall findings suggest that exon 6 SV-16 is more potent than in/del-10 for IRF5-driven resistance to apoptosis and promotion of cytokine production; however, in/del-10 co-expression can neutralize these effects of SV-16.
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Affiliation(s)
- Feng Wen
- Arthritis and Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
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Oberst MD, Beberman SJ, Zhao L, Yin JJ, Ward Y, Kelly K. TDAG51 is an ERK signaling target that opposes ERK-mediated HME16C mammary epithelial cell transformation. BMC Cancer 2008; 8:189. [PMID: 18597688 PMCID: PMC2474852 DOI: 10.1186/1471-2407-8-189] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 07/02/2008] [Indexed: 11/10/2022] Open
Abstract
Introduction Signaling downstream of Ras is mediated by three major pathways, Raf/ERK, phosphatidylinositol 3 kinase (PI3K), and Ral guanine nucleotide exchange factor (RalGEF). Ras signal transduction pathways play an important role in breast cancer progression, as evidenced by the frequent over-expression of the Ras-activating epidermal growth factor receptors EGFR and ErbB2. Here we investigated which signal transduction pathways downstream of Ras contribute to EGFR-dependent transformation of telomerase-immortalized mammary epithelial cells HME16C. Furthermore, we examined whether a highly transcriptionally regulated ERK pathway target, PHLDA1 (TDAG51), suggested to be a tumor suppressor in breast cancer and melanoma, might modulate the transformation process. Methods Cellular transformation of human mammary epithelial cells by downstream Ras signal transduction pathways was examined using anchorage-independent growth assays in the presence and absence of EGFR inhibition. TDAG51 protein expression was down-regulated by interfering small hairpin RNA (shRNA), and the effects on cell proliferation and death were examined in Ras pathway-transformed breast epithelial cells. Results Activation of both the ERK and PI3K signaling pathways was sufficient to induce cellular transformation, which was accompanied by up-regulation of EGFR ligands, suggesting autocrine EGFR stimulation during the transformation process. Only activation of the ERK pathway was sufficient to transform cells in the presence of EGFR inhibition and was sufficient for tumorigenesis in xenografts. Up-regulation of the PHLDA1 gene product, TDAG51, was found to correlate with persistent ERK activation and anchorage-independent growth in the absence or presence of EGFR inhibition. Knockdown of this putative breast cancer tumor-suppressor gene resulted in increased ERK pathway activation and enhanced matrix-detached cellular proliferation of Ras/Raf transformed cells. Conclusion Our results suggest that multiple Ras signal transduction pathways contribute to mammary epithelial cell transformation, but that the ERK signaling pathway may be a crucial component downstream of EGFR activation during tumorigenesis. Furthermore, persistent activation of ERK signaling up-regulates TDAG51. This event serves as a negative regulator of both Erk activation as well as matrix-detached cellular proliferation and suggests that TDAG51 opposes ERK-mediated transformation in breast epithelial cells.
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Affiliation(s)
- Michael D Oberst
- Cell and Cancer Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 1066, Bethesda, MD 20892, USA.
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Walen KH. Spontaneous cell transformation: karyoplasts derived from multinucleated cells produce new cell growth in senescent human epithelial cell cultures. In Vitro Cell Dev Biol Anim 2004; 40:150-8. [PMID: 15479119 DOI: 10.1290/1543-706x(2004)40<150:sctkdf>2.0.co;2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Previously, it was shown that SV40-induced cell transformation of human diploid (2N), epithelial cells was a dynamic process of nuclear and cellular events. In this process, nuclei of polyploid (above 2N) cells broke down into multinucleated cells (MNCs) by amitotic division. An induced mass karyoplast (i.e., small cell with reduced amount of cytoplasm) budding process from the MNCs produced transformed cells with extended life span (EL) and altered morphology. In this study, without the use of SV40 and no induction of karyoplast budding, the same sequence of cellular events was found to occur spontaneously for the same type of cells at replicative senescence (no mitosis). These cell transformation events were followed by phase-contrast photography of living cell cultures. Primary, diploid, epithelial cell cultures grew for two to three passages and then entered senescence. Cells remaining in the cultures after widespread cell death (mortality stage 1; M1) developed the typical large, flat-cell morphology of senescence with increased cytoplasmic volume. Some of these cells were MNCs, mostly with two to four nuclei. Cytokinesis in MNCs and spontaneous karyoplast budding from MNCs were observed, and new, limited EL cell growth was present either in foci of cells or as prolonged cell growth over one to two passages. At the end of their replicative phase, the EL cells entered another death crisis (M2) from which no cells survived. In M2-crisis, rarely transformed cells appear with immortal cell growth characteristics (i.e., cell lines). Numerous examples of fragmentation or amitosis of polyploid nuclei in the production of multinucleated cells (MNCs) are presented. Such nuclear divisions produced nuclei with unequal sizes, which suggest unbalanced chromosomal segregations. The nuclear and cellular events in cell transformation are compared with a natural (no induction) occurrence of MNC-offspring cells in mammalian placentas. The possibility of a connection between these two processes is discussed. And finally the difference in the duration of EL cell growth from SV40-MNCs versus from senescent-MNCs is ascribed to increased mutational load in SV40-induced MNCs as compared with that in senescence MNCs.
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Affiliation(s)
- Kirsten H Walen
- Viral and Rickettsial Disease Laboratory, California Department of Health Services, 850 Marina Bay Parkway, Richmond, California 94804, USA.
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Kusakari T, Kariya M, Mandai M, Tsuruta Y, Hamid AA, Fukuhara K, Nanbu K, Takakura K, Fujii S. C-erbB-2 or mutant Ha-ras induced malignant transformation of immortalized human ovarian surface epithelial cells in vitro. Br J Cancer 2004; 89:2293-8. [PMID: 14676809 PMCID: PMC2395276 DOI: 10.1038/sj.bjc.6601423] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ovarian cancer is believed to develop from the ovarian surface epithelium through the accumulation of aberrations of oncogenes and/or tumor suppressor genes. However, it is unclear how the gene abnormalities are involved in ovarian carcinogenesis. To elucidate the process, we transfected genes reported to show their abnormalities in human ovarian cancers into human ovarian surface epithelial cells. Immortalization of the cells was achieved by the transfection of SV40 large T antigen (LT) and human telomerase reverse transcriptase (hTERT); however, the resultant cells showed no tumorigenesis. Additional transfection of either c-erbB-2 or mutant Ha-ras into the immortalized cells showed the anchorage-independent growth and tumorigenesis in mice with the incidence of 50% and 40%, respectively. Histologically, all the tumours were undifferentiated. In association with the tumorigenesis, the cells expressing c-erbB-2 or mutant Ha-ras demonstrated increased vascular endothelial growth factor secretion under hypoxia and enhanced resistance to apoptosis compared with the immortalized cells. Collectively, the introduction of either c-erbB-2 or mutant Ha-ras in the cells, which were efficiently immortalized by the transfection of LT and hTERT, showed tumorigenicity, suggesting that c-erbB-2 or mutant Ha-ras genes might be involved in ovarian carcinogenesis.
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Affiliation(s)
- T Kusakari
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - M Kariya
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan. E-mail:
| | - M Mandai
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - Y Tsuruta
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - A A Hamid
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - K Fukuhara
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - K Nanbu
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - K Takakura
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
| | - S Fujii
- Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-5807, Japan
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Abstract
Human epithelial cells encounter two senescence barriers that enforce a limited proliferative potential. A first barrier is mediated by the retinoblastoma protein, and can be overcome by multiple types of errors, many of which are observed in human cancers. A second, extremely stringent telomere-dependent barrier, is a consequence of repression of telomerase activity. Although relieved by ectopic hTERT expression, the nature of the errors required to overcome this latter barrier during in vivo carcinogenesis have not yet been defined. Attainment of immortality and telomerase reactivation are crucial to human carcinoma development; the derangements responsible for attainment of immortality may be rate-limiting and permissive for further progression to malignancy.
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Dumble ML, Croager EJ, Yeoh GCT, Quail EA. Generation and characterization of p53 null transformed hepatic progenitor cells: oval cells give rise to hepatocellular carcinoma. Carcinogenesis 2002; 23:435-45. [PMID: 11895858 DOI: 10.1093/carcin/23.3.435] [Citation(s) in RCA: 170] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Oval cells are bipotential liver stem cells able to differentiate into hepatocytes and bile duct epithelia. In normal adult liver oval cells are quiescent, existing in low numbers around the periportal region, and proliferate following severe, prolonged liver trauma. There is evidence implicating oval cells in the development of hepatocellular carcinoma, and hence the availability of an immortalized oval cell line would be invaluable for the study of liver cell lineage differentiation and carcinogenesis. A novel approach in the generation of cell lines is the use of the p53 knockout mouse. Absence of p53 allows a cell to cycle past the normal Hayflick limit, rendering it immortalized, although subsequent genetic alterations are thought necessary for transformation. p53 knockout mice were fed a choline-deficient, ethionine-supplemented diet, previously shown to increase oval cell numbers in wild-type mice. The oval cells were isolated by centrifugal elutriation and maintained in culture. Colonies of hepatic cells were isolated and characterized with respect to phenotype, growth characteristics and tumorigenicity. Analysis of gene expression by Northern blotting and immunocytochemistry suggests they are oval-like cells by virtue of albumin and transferrin expression, as well as the oval cell markers alpha fetoprotein, M(2)-pyruvate kinase and A6. Injection into athymic nude mice shows the cell lines are capable of forming tumors which phenotypically resemble hepatocellular carcinoma. Thus, the use of p53 null hepatic cells successfully generated immortalized and tumorigenic hepatic stem cell lines. The results presented support the idea that deleting p53 allows immortalization and contributes to the transformation of the oval-like cell lines. Further, the tumorigenic status of the cell lines is direct evidence for the participation of oval cells in the formation of hepatocellular carcinoma.
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Affiliation(s)
- Melissa L Dumble
- Department of Biochemistry, The University of Western Australia, Crawley, 6009, Australia
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15
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Iype, Michael, Verma, Iype. Development and characterization of new immortalized human breast cell lines. Cytotechnology 1998; 26:207-18. [PMID: 9618944 PMCID: PMC3449551 DOI: 10.1023/a:1007953429252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
New human breast cell lines were developed from metastatic breast cancer tissues and normal breast tissues. Primary cultures were initiated from cellular outgrowths of explanted tissues or from mechanically isolated cells in two serum-free media. Cell cultures derived from both cancer and normal tissues were immortalized with pRSV-T plasmid to generate permanent breast cell lines that exhibited an epithelial morphology. Cell lines generated in this study were characterized with respect to morphology, growth rate, karyotype, presence of specific genes, and the expression of epithelial and breast markers. The cell lines expressed the epithelial cell markers, cytokeratins 8 and 18, and retained the capacity to produce human milk fat globulin. They also express the BRCA-1, erbB2, and EGF receptor genes and possess the H-ras, K-ras, and p53 genes. Preliminary data showed that one of the new cancer cell lines was highly sensitive to the cytotoxic action of taxol. It is envisioned that the new breast cell lines will be useful as targets for identification of therapeutic agents against breast cancer and as models for carcinogenesis studies.
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Affiliation(s)
- Iype
- Biological Research Faculty and Facility, Inc., Ijamsville, Maryland 21754, USA
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16
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Kao CY, Oakley CS, Welsch CW, Chang CC. Growth requirements and neoplastic transformation of two types of normal human breast epithelial cells derived from reduction mammoplasty. In Vitro Cell Dev Biol Anim 1997; 33:282-8. [PMID: 9156344 DOI: 10.1007/s11626-997-0048-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A chemically defined culture medium was developed to support the growth of two distinctly different types of normal human breast epithelial cells (HBEC) derived from reduction mammoplasty. Type I cells expressed luminal epithelial cell markers and were deficient in gap junctional intercellular communication (GJIC), whereas Type II cells expressed basal epithelial cell markers and were efficient in GJIC. In this study, we examined and compared the growth factor and hormone requirements of these two types of cells and a series of cell lines that were obtained by sequential transfection with SV40 DNA (extended lifespan, nontumorigenic), treatment with 5-bromodeoxyuridine (BrdU)/black light (immortal and weakly tumorigenic), and infection of a virus carrying the neu oncogene (highly tumorigenic). Growth of Type I cells was inhibited by withdrawing epidermal growth factor (EGF), hydrocortisone (HC), or insulin (INS) from the culture media, but was enhanced by fetal bovine serum (FBS) supplementation. Growth of Type II cells was inhibited by withdrawal of EGF, HC, or INS from the media, and was inhibited by FBS supplementation. Withdrawal of human transferrin (HT) or 17 beta-estradiol (E2) from the media did not alter the growth of Type I or Type II cells. SV40 transfected Type I cell lines still required EGF, HC, or INS for optimal growth. However, the highly tumorigenic cell line did not show a growth dependence on EGF, HC, or INS but did appear to require HT and 3,3',5-triiodo-D.L. thyronine (T3) for optimal growth. In addition, FBS stimulated the growth of these cell lines. Thus, this study shows that Type I HBEC are distinctly different from Type II HBEC in growth response to FBS and that neoplastically transformed Type I cells could become growth factor and hormone independent.
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Affiliation(s)
- C Y Kao
- Department of Pediatrics/Human Development, College of Human Medicine, Michigan State University, East Lansing 48824, USA
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17
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Wynford-Thomas D. Proliferative lifespan checkpoints: cell-type specificity and influence on tumour biology. Eur J Cancer 1997; 33:716-26. [PMID: 9282110 DOI: 10.1016/s0959-8049(97)00064-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Lifespan checkpoints are viewed here as intrinsic mechanisms which desensitise cells to external growth signals as a programmed response to proliferative age, as distinct from externally-triggered differentiation. This review focuses on the role of tumour suppressor gene products as essential mediators of cell cycle arrest at lifespan checkpoints, concentrating in particular on p53. Although drawing inevitably on fibroblast senescence and telomere erosion paradigms, other lifespan clocks and signal pathways are discussed. Particular emphasis is placed on cell-type diversity in the nature, number and timing of lifespan checkpoints and its importance for tumour biology. Breast and thyroid cancer are used to illustrate the concept that the "choice" of checkpoint(s) in a given normal cell may have a determining influence on the mutational spectrum and clinical behaviour of its tumours.
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Affiliation(s)
- D Wynford-Thomas
- Department of Pathology, University of Wales College of Medicine, Cardiff, U.K
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19
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Shay JW, Tomlinson G, Piatyszek MA, Gollahon LS. Spontaneous in vitro immortalization of breast epithelial cells from a patient with Li-Fraumeni syndrome. Mol Cell Biol 1995; 15:425-32. [PMID: 7799951 PMCID: PMC231985 DOI: 10.1128/mcb.15.1.425] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Individuals with germ line mutations in the p53 gene, such as Li-Fraumeni syndrome (LFS), have an increased occurrence of many types of cancer, including an unusually high incidence of breast cancer. This report documents that normal breast epithelial cells obtained from a patient with LFS (with a mutation at codon 133 of the p53 gene) spontaneously immortalized in cell culture while the breast stromal fibroblasts from this same patient did not. Spontaneous immortalization of human cells in vitro is an extremely rare event. This is the first documented case of the spontaneous immortalization of breast epithelial cells from a patient with LFS in culture. LFS patient breast stromal fibroblasts infected with a retroviral vector containing human papillomavirus type 16 E7 alone were able to immortalize, whereas stromal cells obtained from patients with wild-type p53, similarly infected with human papillomavirus type 16 E7, did not. The present results indicate a protective role of normal pRb-like functions in breast stromal fibroblasts but not in breast epithelial cells and reinforces an important role of wild-type p53 in the regulation of the normal growth and development of breast epithelial tissue.
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Affiliation(s)
- J W Shay
- Department of Cell Biology and Neurosciences, University of Texas Southwestern Medical Center at Dallas 75235-9039
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20
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Stamps AC, Davies SC, Burman J, O'Hare MJ. Analysis of proviral integration in human mammary epithelial cell lines immortalized by retroviral infection with a temperature-sensitive SV40 T-antigen construct. Int J Cancer 1994; 57:865-74. [PMID: 8206680 DOI: 10.1002/ijc.2910570616] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A panel of eight conditionally immortal lines derived by infection of human breast epithelial cells with an amphotropic retrovirus transducing a ts mutant of SV40 large T-antigen was analyzed with respect to individual retroviral integration patterns. Each line contained multiple integration sites which were clonal and stable over extended passage. Similar integration patterns were observed between individual lines arising separately from the same stock of pre-immortal cells, suggesting a common progenitor. Retroviral integration analysis of pre-immortal cells at different stages of pre-crisis growth showed changes indicative of a progressive transition from polyclonality to clonality as the cells approached crisis. Each of the immortal lines contained a sub-set of the integration sites of their pre-immortal progenitors, with individual combinations and copy numbers of sites. Since all the cell lines appeared to originate from single foci in separate flasks, it is likely that each set arose from a common clone of pre-immortal cells as the result of separate genetic events. There was no evidence from this analysis to suggest that specific integration sites played any part either in the selection of pre-crisis clones or in the subsequent establishment of immortal lines.
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Affiliation(s)
- A C Stamps
- Haddow Laboratories, Institute of Cancer Research, Sutton, Surrey, UK
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21
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Shay JW, Wright WE, Werbin H. Toward a molecular understanding of human breast cancer: a hypothesis. Breast Cancer Res Treat 1993; 25:83-94. [PMID: 8518411 DOI: 10.1007/bf00662404] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A rate limiting step in most metastatic breast cancers is the development of unlimited proliferative potential by mammary epithelial cells. We describe mechanisms by which these cells can attain this state. The two independent mortality mechanisms controlling fibroblast senescence and immortalization (M1 and M2) are also found in human mammary epithelial cells. However, although both p53 and Rb are involved in the M1 mechanism of fibroblast cellular senescence, in human mammary epithelial cells only p53 is involved. The M1/M2 mechanisms may be induced by the gradual loss of telomere ends that occur as normal cells divide. Loss of telomere ends may result in genomic instability and in altered gene expression due to heterochromatin changes in subtelomeric regions. Events which can abrogate p53 functions are described, as is the current state of knowledge about the function of p53. All these factors are included in a molecular model for the onset of breast cancer.
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Affiliation(s)
- J W Shay
- Department of Cell Biology and Neuroscience, University of Texas Southwestern Medical Center, Dallas 75235-9039
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