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Targeting GPCRs and Their Signaling as a Therapeutic Option in Melanoma. Cancers (Basel) 2022; 14:cancers14030706. [PMID: 35158973 PMCID: PMC8833576 DOI: 10.3390/cancers14030706] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 01/27/2022] [Accepted: 01/27/2022] [Indexed: 12/10/2022] Open
Abstract
Simple Summary Sixteen G-protein-coupled receptors (GPCRs) have been involved in melanogenesis or melanomagenesis. Here, we review these GPCRs, their associated signaling, and therapies. Abstract G-protein-coupled receptors (GPCRs) serve prominent roles in melanocyte lineage physiology, with an impact at all stages of development, as well as on mature melanocyte functions. GPCR ligands are present in the skin and regulate melanocyte homeostasis, including pigmentation. The role of GPCRs in the regulation of pigmentation and, consequently, protection against external aggression, such as ultraviolet radiation, has long been established. However, evidence of new functions of GPCRs directly in melanomagenesis has been highlighted in recent years. GPCRs are coupled, through their intracellular domains, to heterotrimeric G-proteins, which induce cellular signaling through various pathways. Such signaling modulates numerous essential cellular processes that occur during melanomagenesis, including proliferation and migration. GPCR-associated signaling in melanoma can be activated by the binding of paracrine factors to their receptors or directly by activating mutations. In this review, we present melanoma-associated alterations of GPCRs and their downstream signaling and discuss the various preclinical models used to evaluate new therapeutic approaches against GPCR activity in melanoma. Recent striking advances in our understanding of the structure, function, and regulation of GPCRs will undoubtedly broaden melanoma treatment options in the future.
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McKillop IH, Girardi CA, Thompson KJ. Role of fatty acid binding proteins (FABPs) in cancer development and progression. Cell Signal 2019; 62:109336. [PMID: 31170472 DOI: 10.1016/j.cellsig.2019.06.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/31/2019] [Accepted: 06/01/2019] [Indexed: 01/06/2023]
Abstract
Fatty acid binding proteins (FABPs) are small, water soluble proteins that bind long chain fatty acids and other biologically active ligands to facilitate intracellular localization. Twelve FABP family members have been identified to date, with 10 isoforms expressed in humans. Functionally, FABPs are important in fatty acid metabolism and transport, with distinct family members having the capacity to influence gene transcription. Expression of FABPs is usually cell/tissue specific to one predominant FABP family member. Dysregulation of FABP expression can occur through genetic mutation and/or environmental-lifestyle influences. In addition to intracellular function, exogenous, circulating FABP expression can occur and is associated with specific disease states such as insulin resistance. A role for FABPs is increasingly being reported in tumor biology with elevated exogenous FABP expression being associated with tumor progression and invasiveness. However, a less clear role has been appreciated for dysregulated FABP expression during cell transformation and early expansion.
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Affiliation(s)
- Iain H McKillop
- Department of Surgery, Carolinas Medical Center, Atrium Health, Charlotte, NC 28203, USA
| | - Cara A Girardi
- Department of Surgery, Carolinas Medical Center, Atrium Health, Charlotte, NC 28203, USA
| | - Kyle J Thompson
- Department of Surgery, Carolinas Medical Center, Atrium Health, Charlotte, NC 28203, USA.
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Mehjabin R, Chen L, Huang R, Zhu D, Yang C, Li Y, Liao L, He L, Zhu Z, Wang Y. Expression and localization of grass carp pkc-θ (protein kinase C theta) gene after its activation. FISH & SHELLFISH IMMUNOLOGY 2019; 87:788-795. [PMID: 30716520 DOI: 10.1016/j.fsi.2019.01.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/26/2019] [Accepted: 01/31/2019] [Indexed: 06/09/2023]
Abstract
Haemorrhagic disease caused by grass carp reovirus (GCRV) can result in large-scale death of young grass carp, leading to irreparable economic losses that seriously affect large-scale breeding. Protein kinase C (PKC, also known as PRKC) represents a family of serine/threonine protein kinases that includes multiple isozymes in many species. Among these, PKC-θ (PKC theta, also written as PRKCQ) is a novel isoform, mainly expressed in T cells, that is known to be involved in immune system function in mammals. To date, no research on immunological functions of fish Pkc-θ has been reported. To address this issue, we cloned the grass carp pkc-θ gene. Phylogenetic and syntenic analysis showed that this gene is the most evolutionarily conserved relative to zebrafish. Real-time quantitative PCR (RT-qPCR) indicated that pkc-θ was expressed at high levels in the gills and spleen of healthy grass carp. Infection with GCRV down regulated pkc-θ expression in the gills and spleen. Gene products that function upstream and downstream of pkc-θ were up regulated in the gill, but were down-regulated in the spleen. These results suggest that direct or indirect targeting of pkc-θ by GCRV may help the virus evade host immune defences in the spleen. Phorbol ester (PMA) treatment of Jurkat T cells induced translocation of grass carp Pkc-θ from the cytoplasm to the plasma membrane. This response to PMA suggests evolutionary conservation of an immune response function in fish Pkc-θ, as well as conservation of its sequence and structural domains. This study expanded our knowledge of the fish PKC gene family, and explored the role of pkc-θ in function of the grass carp immune system, providing new insights which may facilitate further studies of its biological functions.
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Affiliation(s)
- Rumana Mehjabin
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Liangming Chen
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Rong Huang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
| | - Denghui Zhu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Cheng Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yongming Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Lanjie Liao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Libo He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Zuoyan Zhu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yaping Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
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Amiri M, Yousefnia S, Seyed Forootan F, Peymani M, Ghaedi K, Nasr Esfahani MH. Diverse roles of fatty acid binding proteins (FABPs) in development and pathogenesis of cancers. Gene 2018; 676:171-183. [PMID: 30021130 DOI: 10.1016/j.gene.2018.07.035] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 07/04/2018] [Accepted: 07/12/2018] [Indexed: 12/27/2022]
Abstract
One of the most importantly involved pathways in cancer development is fatty-acid signaling pathway. Synthesized lipids as energetic sources are consumed by cancer cells for proliferation, growth, survival, invasion and angiogenesis. Fatty acids as signaling compounds regulate metabolic and transcriptional networks, survival pathways and inflammatory responses. Aggregation of fatty acids with fatty acid binding proteins (FABPs) facilitates their transportation to different cell organelles. FABPs, a group of lipid binding proteins modulate fatty acid metabolism, cell growth and proliferation and cancer development. They may be used as tumor marker in some cancers. FABPs are expressed in most malignancies such as prostate, breast, liver, bladder and lung cancer which are associated with the incidence, proliferation, metastasis, invasion of tumors. This review introduces several isoforms of FABPs (FABP1-12) and summarizes their function and their possible roles in cancer development through some proposed mechanisms.
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Affiliation(s)
- Mina Amiri
- Department of Modern Biology, ACECR Institute of Higher Education (Isfahan Branch), Isfahan, Iran
| | - Saghar Yousefnia
- Division of Cellular and Molecular Biology, Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran
| | - Farzad Seyed Forootan
- Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran; Legal Medicine Research Center, Legal Medicine Organization, Tehran, Iran.
| | - Maryam Peymani
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran; Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Kamran Ghaedi
- Division of Cellular and Molecular Biology, Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran; Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
| | - Mohammad Hossein Nasr Esfahani
- Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
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Tseng T, Uen W, Tseng J, Lee S. Enhanced chemosensitization of anoikis-resistant melanoma cells through syndecan-2 upregulation upon anchorage independency. Oncotarget 2017; 8:61528-61537. [PMID: 28977882 PMCID: PMC5617442 DOI: 10.18632/oncotarget.18616] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 05/29/2017] [Indexed: 01/05/2023] Open
Abstract
Syndecan family proteins are heparan sulfate proteoglycans, which involved in various cellular activities and associating with metastatic potential and chemosensitivity of tumor cells. Melanoma is one of malignant tumors with poor prognosis upon metastasis. Previously, we had shown that melanoma cells remained survived under cell detachment, which was similar to the initial steps of tumor metastasis. Downregulation of syndecan-1 and upregulation of syndecan-2 in melanoma A375 cells were observed by different suspension conditions. Specific gene alterations also increased melanoma malignancy under anchorage independency. Thus, we would like to investigate in further the role of specific gene alteration, so that it could be used to develop novel strategy to treat melanoma. In this paper, we found that syndecan-2 expression level as well the kinase phosphorylation levels increased upon anchorage independency. The pathway to regulate syndecan-2 expression shifted from PKCα/β-dependent under adhesion into PKCδ-dependent under cell suspension. Manipulation of syndecan-2 expression showed that PI3K and ERK phosphorylation as well the migratory ability increased with increased syndecan-2 expression level. In addition, suspended melanoma cells were more sensitive to chemoagents, which correlated with syndecan-2 overexpression, PI3K and ERK activations, serum level, and the presence of glycosaminoglycans. In conclusion, we showed upregulation of syndecan-2 in anoikis-resistant melanoma cells enhanced chemosensitivity through PI3K and ERK activation. This observation would support and refine the strategy of adjuvant chemotherapy to overcome metastatic melanoma.
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Affiliation(s)
- TingTing Tseng
- School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan
| | - WuChing Uen
- School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan.,Department of Hematology and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei City 111, Taiwan
| | - JenChih Tseng
- School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan
| | - ShaoChen Lee
- School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan
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Noppakunmongkolchai W, Poyomtip T, Jittawuttipoka T, Luplertlop N, Sakuntabhai A, Chimnaronk S, Jirawatnotai S, Tohtong R. Inhibition of protein kinase C promotes dengue virus replication. Virol J 2016; 13:35. [PMID: 26931565 PMCID: PMC4774189 DOI: 10.1186/s12985-016-0494-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 02/23/2016] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Dengue virus (DENV) is a member of the Flaviviridae family, transmitted to human via mosquito. DENV infection is common in tropical areas and occasionally causes life-threatening symptoms. DENV contains a relatively short positive-stranded RNA genome, which encodes ten viral proteins. Thus, the viral life cycle is necessarily rely on or regulated by host factors. METHODS In silico analyses in conjunction with in vitro kinase assay were used to study kinases that potentially phosphorylate DENV NS5. Potential kinase was inhibited or activated by a specific inhibitor (or siRNA), or an activator. Results of the inhibition and activation on viral entry/replication and host cell survival were examined. RESULTS Our in silico analyses indicated that the non-structural protein 5 (NS5), especially the RNA-dependent RNA polymerase (RdRp) domain, contains conserved phosphorylation sites for protein kinase C (PKC). Phosphorylation of NS5 RdRp was further verified by PKC in vitro kinase assay. Inhibitions of PKC by a PKC-specific chemical inhibitor or siRNA suppressed NS5 phosphorylation in vivo, increased viral replication and reduced viability of the DENV-infected cells. In contrary, activation of PKC effectively suppressed intracellular viral number. CONCLUSIONS These results indicated that PKC may act as a restricting mechanism that modulates the DENV replication and represses the viral outburst in the host cells.
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Affiliation(s)
| | - Teera Poyomtip
- Department of Microbiology, Faculty of Sciences, Mahidol University, Bangkok, Thailand.
| | | | - Natthanej Luplertlop
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Thailand Functional Genetics of Infectious Diseases Unit, Institute, Mahidol University, Bangkok, Thailand.
| | - Anavaj Sakuntabhai
- Institute Pasteur, Functional Genetics of Infectious Diseases Unit, Paris, France. .,Centre National de la Recherche Scientifique (CNRS), URA3012, F-75015, Paris, France. .,Systems Biology of Diseases Research Unit, Faculty of Science, Mahidol University, Bangkok, Thailand.
| | - Sarin Chimnaronk
- Institute of Molecular Biosciences, Mahidol University, Salaya, Nakhon Pathom, Thailand. .,Systems Biology of Diseases Research Unit, Faculty of Science, Mahidol University, Bangkok, Thailand.
| | - Siwanon Jirawatnotai
- Systems Biology of Diseases Research Unit, Faculty of Science, Mahidol University, Bangkok, Thailand. .,Laboratory for Systems Pharmacology, Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Bangkok, Thailand.
| | - Rutaiwan Tohtong
- Department of Biochemistry, Faculty of Sciences, Mahidol University, Bangkok, Thailand.
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Carduner L, Picot CR, Leroy-Dudal J, Blay L, Kellouche S, Carreiras F. Cell cycle arrest or survival signaling through αv integrins, activation of PKC and ERK1/2 lead to anoikis resistance of ovarian cancer spheroids. Exp Cell Res 2013; 320:329-42. [PMID: 24291221 DOI: 10.1016/j.yexcr.2013.11.011] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 11/11/2013] [Accepted: 11/14/2013] [Indexed: 11/24/2022]
Abstract
Ovarian cancer is the most lethal gynecologic cancer mainly due to spheroids organization of cancer cells that disseminate within the peritoneal cavity. We have investigated the molecular mechanisms by which ovarian cancer spheroids resist anoikis, choosing as models the 2 well-characterized human ovarian cancer cell lines IGROV1 and SKOV3. These cell lines have the propensity to float as clusters, and were isolated from tumor tissue and ascites, respectively. To form spheroids, IGROV1 and SKOV3 ovarian adenocarcinoma cells were maintained under anchorage-independent culture conditions, in which both lines survive at least a week. A short apoptotic period prior to a survival signaling commitment was observed for IGROV1 cells whereas SKOV3 cells entered G0/G1 phase of the cell cycle. This difference in behavior was due to different signals. With regard to SKOV3 cells, activation of p38 and an increase in p130/Rb occurred once anchorage-independent culture was established. Analyses of the survival signaling pathway switched on by IGROV1 cells showed that activation of ERK1/2 was required to evade apoptosis, an effect partly dependent on PKC activation and αv integrins. αv-integrin expression is essential for survival through activation of ERK1/2 phosphorylation. The above data indicate that ovarian cancer cells can resist anoikis in the spheroid state by arrest in the cell cycle or through activation of αv-integrin-ERK-mediated survival signals. Such signaling might result in the selection of resistant cells within disseminating spheroids, favoring further relapse in ovarian cancers.
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Affiliation(s)
- Ludovic Carduner
- Equipe de Recherche sur les Relations Matrice Extracellulaire Cellules, ERRMECe (EA 1391), Institut des Matériaux, Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France
| | - Cédric R Picot
- Equipe de Recherche sur les Relations Matrice Extracellulaire Cellules, ERRMECe (EA 1391), Institut des Matériaux, Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France.
| | - Johanne Leroy-Dudal
- Equipe de Recherche sur les Relations Matrice Extracellulaire Cellules, ERRMECe (EA 1391), Institut des Matériaux, Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France
| | - Lyvia Blay
- Equipe de Recherche sur les Relations Matrice Extracellulaire Cellules, ERRMECe (EA 1391), Institut des Matériaux, Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France
| | - Sabrina Kellouche
- Equipe de Recherche sur les Relations Matrice Extracellulaire Cellules, ERRMECe (EA 1391), Institut des Matériaux, Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France
| | - Franck Carreiras
- Equipe de Recherche sur les Relations Matrice Extracellulaire Cellules, ERRMECe (EA 1391), Institut des Matériaux, Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France
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Smith SD, Enge M, Bao W, Thullberg M, Costa TDF, Olofsson H, Gashi B, Selivanova G, Strömblad S. Protein kinase Cα (PKCα) regulates p53 localization and melanoma cell survival downstream of integrin αv in three-dimensional collagen and in vivo. J Biol Chem 2012; 287:29336-47. [PMID: 22773839 DOI: 10.1074/jbc.m112.341917] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Protein kinase C α (PKCα) is overexpressed in numerous types of cancer. Importantly, PKCα has been linked to metastasis of malignant melanoma in patients. However, it has been unclear how PKCα may be regulated and how it exerts its role in melanoma. Here, we identified a role for PKCα in melanoma cell survival in a three-dimensional collagen model mimicking the in vivo pathophysiology of the dermis. A pathway was identified that involved integrin αv-mediated up-regulation of PKCα and PKCα-dependent regulation of p53 localization, which was connected to melanoma cell survival. Melanoma survival and growth in three-dimensional microenvironments requires the expression of integrin αv, which acts to suppress p53 activity. Interestingly, microarray analysis revealed that PKCα was up-regulated by integrin αv in a three-dimensional microenvironment-dependent manner. Integrin αv was observed to promote a relocalization of endogenous p53 from the nucleus to the cytoplasm upon growth in three-dimensional collagen as well as in vivo, whereas stable knockdown of PKCα inhibited the integrin αv-mediated relocalization of p53. Importantly, knockdown of PKCα also promoted apoptosis in three-dimensional collagen and in vivo, resulting in reduced tumor growth. This indicates that PKCα constitutes a crucial component of the integrin αv-mediated pathway(s) that promote p53 relocalization and melanoma survival.
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Affiliation(s)
- Stephen D Smith
- Department of Biosciences and Nutrition, Center for Biosciences, Karolinska Institutet, Huddinge SE-141 83, Sweden
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Zheng Y, Sarr MG. Translocation of transfected GLUT2 to the apical membrane in rat intestinal IEC-6 cells. Dig Dis Sci 2012; 57:1203-12. [PMID: 22116644 PMCID: PMC3331913 DOI: 10.1007/s10620-011-1984-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 11/10/2011] [Indexed: 02/01/2023]
Abstract
AIM In this study, we transfected the full length cDNA of glucose transporter 2 (GLUT2) into IEC-6 cells (which lack GLUT2 expression) to investigate GLUT2 translocation in enterocytes. The purpose of this study was to investigate cellular mechanisms of GLUT2 translocation and its signaling pathway. METHODS Rat GLUT2 cDNA was transfected into IEC-6 cells. Glucose uptake was measured by incubating cell monolayers with glucose (0.5-50 mM), containing (14)C-D-glucose and (3)H-L-glucose, to measure stereospecific, carrier-mediated and passive uptake. We imaged GLUT2 immunoreactivity by confocal fluorescence microscopy. We evaluated the GLUT2 inhibitor (1 mM phloretin), SGLT1 inhibitor (0.5 mM phlorizin), disrupting microtubular integrity (2 μM nocodazole and 0.5 μM cytochalasin B), protein kinase C (PKC) inhibitors (50 nM calphostin C and 10 μM chelerythrine), and PKC activator (50 nM phorbol 12-myristate 13-acetate: PMA). RESULTS In GLUT2-IEC cells, the K(m) (54.5 mM) increased compared with non-transfected IEC-6 cells (7.8 mM); phloretin (GLUT2 inhibitor) inhibited glucose uptake to that of non-transfected IEC-6 cells (P < 0.05). Nocodazole and cytochalasin B (microtubule disrupters) inhibited uptake by 43-58% only at glucose concentrations ≥25 and 50 mM and the 10-min incubations. Calphostin C (PKC inhibitor) reproduced the inhibition of nocodazole; PMA (a PKC activator) enhanced glucose uptake by 69%. Exposure to glucose increased the GFP signal at the apical membrane of GLUT-1EC cells. CONCLUSION IEC-6 cells lacking GLUT2 translocate GLUT2 apically when transfected to express GLUT2. Translocation of GLUT2 occurs through glucose stimulation via a PKC-dependent signaling pathway and requires integrity of the microtubular skeletal structure.
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Affiliation(s)
- Ye Zheng
- Department of Surgery and The Gastroenterology Research Unit, Mayo Clinic (GU 10-01), 200 1st Street SW, Rochester, MN 55905, USA.
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Mattia G, Errico MC, Felicetti F, Petrini M, Bottero L, Tomasello L, Romania P, Boe A, Segnalini P, Di Virgilio A, Colombo MP, Carè A. Constitutive activation of the ETS-1-miR-222 circuitry in metastatic melanoma. Pigment Cell Melanoma Res 2011; 24:953-65. [PMID: 21711453 PMCID: PMC3272348 DOI: 10.1111/j.1755-148x.2011.00881.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 06/23/2011] [Indexed: 01/13/2023]
Abstract
MicroRNAs-221 and -222 are highly upregulated in several solid tumors, including melanomas. We demonstrate that the proto-oncogene ETS-1, involved in the pathogenesis of cancers of different origin, is a transcriptional regulator of miR-222 by direct binding to its promoter region. Differently from 293FT cells or early stage melanomas, where unphosphorylated ETS-1 represses miR-222 transcription, in metastatic melanoma the constitutively Thr-38 phosphorylated fraction of ETS-1 induces miR-222. Despite its stepwise decreased expression along with melanoma progression, the oncogenic activity of ETS-1 relies on its RAS/RAF/ERK-dependent phosphorylation status more than on its total amount. To close the loop, we demonstrate ETS-1 as a direct target of miR-222, but not miR-221, showing the novel option of their uncoupled functions. In addition, a spatial redistribution of ETS-1 protein from the nucleus to the cytoplasm is also evidenced in advanced melanoma cells. Finally, in vivo studies confirmed the contribution of miR-222 to the increased invasive potential obtained by ETS- silencing.
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Affiliation(s)
- Gianfranco Mattia
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - M Cristina Errico
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Federica Felicetti
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Marina Petrini
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Lisabianca Bottero
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Luisa Tomasello
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Paolo Romania
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Alessandra Boe
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Patrizia Segnalini
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
| | - Antonio Di Virgilio
- Service for Quality and Safety of Animal Experimentation, Istituto Superiore di SanitàRome, Italy
| | - Mario P Colombo
- Immunotherapy and Gene Therapy Unit, Department of Experimental Oncology, Fondazione IRCCS Istituto Nazionale TumoriMilan, Italy
| | - Alessandra Carè
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore SanitàRome, Italy
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Zheng Y, Scow JS, Duenes JA, Sarr MG. Mechanisms of glucose uptake in intestinal cell lines: role of GLUT2. Surgery 2011; 151:13-25. [PMID: 21943636 DOI: 10.1016/j.surg.2011.07.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Accepted: 07/06/2011] [Indexed: 12/25/2022]
Abstract
BACKGROUND GLUT2 is translocated to the apical membrane of enterocytes exposed to glucose concentrations >∼50 mM. Mechanisms of GLUT2-mediated glucose uptake in cell culture models of enterocytes have not been studied. AIM To explore mechanism(s) of glucose uptake in 3 enterocyte-like cell lines. METHODS Glucose uptake was measured in Caco-2, RIE-1, and IEC-6 cell lines using varying concentrations of glucose (0.5-50 mM). Effects of phlorizin (SGLT1 inhibitor), phloretin (GLUT2 inhibitor), nocodazole and cytochalasin B (disrupters of cytoskeleton), calphostin C and chelerythrine (PKC inhibitors), and phorbol 12-myristate 13-acetate (PKC activator) were evaluated. RESULTS Phlorizin inhibited glucose uptake in all 3 cell lines. Phloretin inhibited glucose uptake in Caco-2 and RIE-1 cells. Starving cells decreased glucose uptake in Caco-2 and RIE-1 cells. Glucose uptake was saturated at >10 mM glucose in all 3 cell lines when exposed briefly (<1 min) to glucose. After exposure for >5 min in Caco-2 and RIE-1 cells, glucose uptake did not saturate and K(m) and V(max) increased. This increase in glucose uptake was inhibited by phloretin, nocodazole, cytochalasin B, calphostin C, and chelerythrine. PMA enhanced glucose uptake by 20%. Inhibitors and PMA had little or no effect in the IEC-6 cells. CONCLUSION Constitutive expression of GLUT2 in the apical membrane along with additional translocation of cytoplasmic GLUT2 to the apical membrane via an intact cytoskeleton and activated PKC appears responsible for enhanced carrier-mediated glucose uptake at greater glucose concentrations (>20 mM) in Caco-2 and RIE-1 cells. IEC-6 cells do not appear to express functional GLUT2.
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Affiliation(s)
- Ye Zheng
- Department of Surgery and the Gastroenterology Research Unit, Mayo Clinic, Rochester, MN 55905, USA
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Wang Z, Trope CG, Flørenes VA, Suo Z, Nesland JM, Holm R. Overexpression of CDC25B, CDC25C and phospho-CDC25C (Ser216) in vulvar squamous cell carcinomas are associated with malignant features and aggressive cancer phenotypes. BMC Cancer 2010; 10:233. [PMID: 20500813 PMCID: PMC2887779 DOI: 10.1186/1471-2407-10-233] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 05/25/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND CDC25 phosphatases are important regulators of the cell cycle. Their abnormal expression detected in a number of tumors implies that their dysregulation is involved in malignant transformation. However, the role of CDC25s in vulvar cancer is still unknown. To shed light on their roles in the pathogenesis and to clarify their prognostic values, expression of CDC25A, CDC25B and CDC25C in a large series of vulvar squamous cell carcinomas were examined. METHODS Expression of CDC25A, CDC25B, CDC25C and phosphorylated (phospho)-CDC25C (Ser216) were examined in 300 vulvar carcinomas using immunohistochemistry. Western blot analysis was utilized to demonstrate CDC25s expression in vulvar cancer cell lines. Kinase and phosphatase assays were performed to exclude cross reactivity among CDC25s isoform antibodies. RESULTS High nuclear CDC25A and CDC25B expression were observed in 51% and 16% of the vulvar carcinomas, respectively, whereas high cytoplasmic CDC25C expression was seen in 63% of the cases. In cytoplasm, nucleus and cytoplasm/nucleus high phospho-CDC25C (Ser216) expression was identified in 50%, 70% and 77% of the carcinomas, respectively. High expression of CDC25s correlated significantly with malignant features, including poor differentiation and infiltration of vessel for CDC25B, high FIGO stage, presence of lymph node metastases, large tumor diameter, poor differentiation for CDC25C and high FIGO stage, large tumor diameter, deep invasion and poor differentiation for phospho-CDC25C (Ser216). In univariate analysis, high expression of phospho-CDC25C (Ser216) was correlated with poor disease-specific survival (p = 0.04). However, such an association was annulled in multivariate analysis. CONCLUSIONS Our results suggest that CDC25C and phospho-CDC25C (Ser216) play a crucial role and CDC25B a minor role in the pathogenesis and/or progression of vulvar carcinomas. CDC25B, CDC25C and phospho-CDC25C (Ser216) were associated with malignant features and aggressive cancer phenotypes. However, the CDC25s isoforms were not independently correlated to prognosis.
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Affiliation(s)
- Zhihui Wang
- Department of Pathology, Oslo University Hospital and University of Oslo, Norway
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13
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Wang Z, Trope CG, Flørenes VA, Suo Z, Nesland JM, Holm R. Overexpression of CDC25B, CDC25C and phospho-CDC25C (Ser216) in vulvar squamous cell carcinomas are associated with malignant features and aggressive cancer phenotypes. BMC Cancer 2010; 10:23. [PMID: 20109227 PMCID: PMC2834618 DOI: 10.1186/1471-2407-10-23] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 01/28/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND CDC25 phosphatases are important regulators of the cell cycle. Their abnormal expression detected in a number of tumors implies that their dysregulation is involved in malignant transformation. However, the role of CDC25s in vulvar cancer is still unknown. To shed light on their roles in the pathogenesis and to clarify their prognostic values, expression of CDC25A, CDC25B and CDC25C in a large series of vulvar squamous cell carcinomas were examined. METHODS Expression of CDC25A, CDC25B, CDC25C and phosphorylated (phospho)-CDC25C (Ser216) were examined in 300 vulvar carcinomas using immunohistochemistry. Western blot analysis was utilized to demonstrate CDC25s expression in vulvar cancer cell lines. Kinase and phosphatase assays were performed to exclude cross reactivity among CDC25s isoform antibodies. RESULTS High nuclear CDC25A and CDC25B expression were observed in 51% and 16% of the vulvar carcinomas, respectively, whereas high cytoplasmic CDC25C expression was seen in 63% of the cases. In cytoplasm, nucleus and cytoplasm/nucleus high phospho-CDC25C (Ser216) expression was identified in 50%, 70% and 77% of the carcinomas, respectively. High expression of CDC25s correlated significantly with malignant features, including poor differentiation and infiltration of vessel for CDC25B, high FIGO stage, presence of lymph node metastases, large tumor diameter, poor differentiation for CDC25C and high FIGO stage, large tumor diameter, deep invasion and poor differentiation for phospho-CDC25C (Ser216). In univariate analysis, high expression of phospho-CDC25C (Ser216) was correlated with poor disease-specific survival (p = 0.04). However, such an association was annulled in multivariate analysis. CONCLUSIONS Our results suggest that CDC25C and phospho-CDC25C (Ser216) play a crucial role and CDC25B a minor role in the pathogenesis and/or progression of vulvar carcinomas. CDC25B, CDC25C and phospho-CDC25C (Ser216) were associated with malignant features and aggressive cancer phenotypes. However, the CDC25s isoforms were not independently correlated to prognosis.
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Affiliation(s)
- Zhihui Wang
- Department of Pathology, Oslo University Hospital and University of Oslo, Norway
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Haughian JM, Bradford AP. Protein kinase C alpha (PKCα) regulates growth and invasion of endometrial cancer cells. J Cell Physiol 2009; 220:112-8. [DOI: 10.1002/jcp.21741] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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15
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Reyland ME. Protein kinase C isoforms: Multi-functional regulators of cell life and death. Front Biosci (Landmark Ed) 2009; 14:2386-99. [PMID: 19273207 DOI: 10.2741/3385] [Citation(s) in RCA: 206] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The protein kinase C (PKC) family consists of 10 related serine/threonine protein kinases some of which are critical regulators of cell proliferation, survival and cell death. While early studies relied on broad spectrum chemical activators or inhibitors of this family, the generation of isoform specific tools has greatly facilitated our understanding of the contribution of specific PKC isoforms to cell proliferation and apoptosis. These studies suggest that PKC-alpha, PKC-epsilon, and the atypical PKC's, PKC-lambda/iota and PKC-zeta, preferentially function to promote cell proliferation and survival, while the novel isoform, PKC-delta is an important regulator of apoptosis. The essential role of this kinase family in both cell survival and apoptosis suggests that specific isoforms may function as molecular sensors, promoting cell survival or cell death depending on environmental cues. Given their central role in cell and tissue homeostasis, it is not surprising that the expression or activity of some of these kinases is altered in human diseases, particularly cancer.
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Affiliation(s)
- Mary E Reyland
- Department of Craniofacial Biology, University of Colorado Health Sciences Center, Aurora, CO 80045, USA.
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Slipicevic A, Jørgensen K, Skrede M, Rosnes AKR, Trøen G, Davidson B, Flørenes VA. The fatty acid binding protein 7 (FABP7) is involved in proliferation and invasion of melanoma cells. BMC Cancer 2008; 8:276. [PMID: 18826602 PMCID: PMC2569959 DOI: 10.1186/1471-2407-8-276] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 09/30/2008] [Indexed: 11/30/2022] Open
Abstract
Background The molecular mechanisms underlying melanoma tumor development and progression are still not completely understood. One of the new candidates that emerged from a recent gene expression profiling study is fatty acid-binding protein 7 (FABP7), involved in lipid metabolism, gene regulation, cell growth and differentiation. Methods We studied the functional role of FABP7 in human melanoma cell lines and using immunohistochemistry analyzed its expression pattern and clinical role in 11 nevi, 149 primary melanomas and 68 metastases. Results FABP7 mRNA and protein level is down-regulated following treatment of melanoma cell lines with a PKC activator (PMA) or MEK1 inhibitor (PD98059). Down-regulation of FABP7 using siRNA decreased cell proliferation and invasion but did not affect apoptosis. In clinical specimens, FABP7 was expressed in 91% of nevi, 71% of primary melanomas and 70% of metastases, with a cytoplasmic and/or nuclear localization. FABP7 expression was associated with tumor thickness in superficial spreading melanoma (P = 0.021). In addition, we observed a trend for an association between FABP7 expression and Ki-67 score (P = 0.070) and shorter relapse-free survival (P = 0.069) in this group of patients. Conclusion Our data suggest that FABP7 can be regulated by PKC and the MAPK/ERK1/2 pathway through independent mechanisms in melanoma cell lines. Furthermore, FABP7 is involved in cell proliferation and invasion in vitro, and may be associated with tumor progression in melanoma.
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Affiliation(s)
- Ana Slipicevic
- Pathology Clinic, Rikshospitalet-Radiumhospitalet Medical Center, Montebello N-0310 Oslo, Norway.
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Tumorigenicity of IL-1alpha- and IL-1beta-deficient fibrosarcoma cells. Neoplasia 2008; 10:549-62. [PMID: 18516292 DOI: 10.1593/neo.08286] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 03/29/2008] [Accepted: 03/29/2008] [Indexed: 12/11/2022] Open
Abstract
Analyzing the growth of fibrosarcoma lines derived from IL-1alpha-, IL-1beta- , or IL-1alphabeta-knockout (-/-) mice in the immunocompetent host revealed that tumor-derived IL-1alpha and IL-1beta exert strong and opposing effects on immune response induction, which prohibited the evaluation of a potential impact on tumorigenicity. Therefore, in vivo growth of IL-1-deficient tumor lines was evaluated in nu/nu mice and was compared with in vitro growth characteristics. All IL-1-deficient fibrosarcoma lines grow in immunocompromised mice. However, IL-1alpha(-/-)beta-competent (comp) lines grow more aggressively, efficiently induce angiogenesis, and recruit inflammatory cells. Despite stronger tumorigenicity of IL-1beta(comp) lines, IL-1alpha strengthens anchorage-independent growth, but both IL-1alpha and IL-1beta support drug resistance. Corresponding to the aggressive growth, IL-1beta(comp) cells display increased matrix adhesion, motility, and cable formation on matrigel, likely supported by elevated alpha(v)/beta3 and matrix metalloroteinase expression. Recruitment of myeloid cells requires IL-1beta but is regulated by IL-1alpha, because inflammatory chemokine and cytokine expression is stronger in IL-1alpha(-/-)beta(comp) than in IL-1(wt) lines. This regulatory effect of tumor-derived IL-1alpha is restricted to the tumor environment and does not affect systemic inflammatory response induction by tumor-derived IL-1beta. Both sarcoma cell-derived IL-1alpha and IL-1beta promote tumor growth. However, IL-1alpha exerts regulatory activity on the tumor cell-matrix cross-talk, and only IL-1beta initiates systemic inflammation.
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Lin CW, Shen SC, Hou WC, Yang LY, Chen YC. Heme oxygenase-1 inhibits breast cancer invasion via suppressing the expression of matrix metalloproteinase-9. Mol Cancer Ther 2008; 7:1195-206. [PMID: 18483307 DOI: 10.1158/1535-7163.mct-07-2199] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the present study, we investigated the antitumor effects of the invasiveness and migration of heme oxygenase 1 (HO-1) in human breast carcinoma cells. 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced matrix metalloproteinase-9 (MMP-9) enzyme activity and gene expression at both protein and mRNA levels were examined in human breast carcinoma cells (MCF-7 and MDA-MB-231), and the addition of the MMP-9 inhibitor, SB3CT, significantly suppressed TPA-induced invasion and migration according to the in vitro Transwell assay. Elevation of HO-1 gene expression by ferric protoporphyrin IX inhibited TPA-induced invasion of MCF-7 cells, which was blocked by adding the heme oxygenase inhibitor, tin protoporphyrin IX, or transfection of cells with HO-1 short hairpin RNA. MCF-7 cells overexpressing HO-1 (MCF-7/HO-1) were established in the present study, and TPA-induced MMP-9 gene expression, tumor invasion, and colony formation were significantly reduced in MCF-7/HO-1 cells, compared with those in Neo-transfected cells. Activation of protein kinase Calpha/extracellular signal-regulated kinases/AP-1 with stimulation of reactive oxygen species production was involved in TPA-induced invasion of MCF-7 cells, which was attenuated by HO-1 protein induced by ferric protoporphyrin IX or transfection of HO-1 expression vectors. Additionally, the addition of carbon monoxide, but not ferric ions, biliverdin, or bilirubin, inhibited TPA-induced invasion through suppressing MMP-9, extracellular signal-regulated kinases, and AP-1 activation stimulated by TPA. The beneficial role of HO-1 in blocking tumor invasion was first identified in this study.
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Affiliation(s)
- Cheng-Wei Lin
- Graduate Institute of Pharmacy, School of Pharmacy, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan, Republic of China
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Friedrich J, Ebner R, Kunz-Schughart LA. Experimental anti-tumor therapy in 3-D: spheroids--old hat or new challenge? Int J Radiat Biol 2008; 83:849-71. [PMID: 18058370 DOI: 10.1080/09553000701727531] [Citation(s) in RCA: 325] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PURPOSE To give a state-of-the-art overview on the promise of three-dimensional (3-D) culture systems for anticancer drug development, with particular emphasis on multicellular tumor spheroids (MCTS). RESULTS AND CONCLUSIONS Cell-based assays have become an integral component in many stages of routine anti-tumor drug testing. However, they are almost always based on homogenous monolayer or suspension cultures and thus represent a rather artificial cellular environment. 3-D cultures--such as the well established spheroid culture system--better reflect the in vivo behavior of cells in tumor tissues and are increasingly recognized as valuable advanced tools for evaluating the efficacy of therapeutic intervention. The present article summarizes past and current applications and particularly discusses technological challenges, required improvements and recent progress with the use of the spheroid model in experimental therapeutics, as a basis for sophisticated drug/therapy screening. A brief overview is given focusing on the nomenclature of spherical 3-D cultures, their potential to mimic many aspects of the pathophysiological situation in tumors, and currently available protocols for culturing and analysis. A list of spheroid-forming epithelial cancer cell lines of different origin is provided and the recent trend to use spheroids for testing combination treatment strategies is highlighted. Finally, various spheroid co-culture approaches are presented that have been established to study heterologous cell interactions in solid tumors and thereby are able to reflect the cellular tumor environment with increasing accuracy. The intriguing observation that in order to retain certain tumor initiating cell properties, some primary tumor cell populations must be maintained exclusively in 3-D culture is mentioned, adding a new but fascinating challenge for future therapeutic campaigns.
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Pereverzev A, Komarova SV, Korcok J, Armstrong S, Tremblay GB, Dixon SJ, Sims SM. Extracellular acidification enhances osteoclast survival through an NFAT-independent, protein kinase C-dependent pathway. Bone 2008; 42:150-61. [PMID: 17964236 DOI: 10.1016/j.bone.2007.08.044] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Revised: 07/24/2007] [Accepted: 08/31/2007] [Indexed: 11/22/2022]
Abstract
Systemic acidosis has detrimental effects on the skeleton and local acidosis is associated with bone destruction in inflammatory and neoplastic diseases. However, the mechanisms by which acidosis enhances osteoclastic bone resorption are poorly understood. Our aim was to examine the effects of acid on osteoclast survival and the involvement of cytosolic Ca(2+) in mediating these effects. Osteoclasts were isolated from long bones of newborn rats, and multinucleated osteoclast-like cells were generated from RAW 264.7 cells. Cytosolic free Ca(2+) concentration ([Ca(2+)](i)) was monitored using fura-2. Survival of rat osteoclasts over a period of 18 h was significantly enhanced by acidification of the medium from 40+/-10% at pH 7.6 to 83+/-4% at pH 7.0. Consistent with its effects on survival, acidosis suppressed osteoclast apoptosis at 6 h. We examined the possible involvement of the proton-sensing receptor ovarian cancer G protein-coupled receptor 1 (OGR1) in mediating the effects of acid. Acid-induced rise of [Ca(2+)](i) was inhibited by the OGR1 antagonist Cu(2+) and was suppressed in osteoclast-like cells in which OGR1 transcripts were depleted using RNA interference. These findings support an essential role for OGR1 in acid-induced Ca(2+) signaling in osteoclasts. Addition of Cu(2+) or chelation of cytosolic Ca(2+) with BAPTA abolished the ability of acidification to enhance osteoclast survival. Inhibition of NFAT activation with the cell-permeable peptide 11R-VIVIT did not alter the ability of acid to promote survival; however, it suppressed the increase in survival induced by RANKL. In contrast, inhibition of protein kinase C (PKC) blocked the effect of acid on osteoclast survival. Thus, this study reveals that extracellular acidification enhances osteoclast survival through an NFAT-independent, PKC-dependent pathway. Increased osteoclast survival may contribute to bone loss in systemic and local acidosis.
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Affiliation(s)
- Alexey Pereverzev
- CIHR Group in Skeletal Development and Remodeling, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada N6A 5C1
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21
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Hindié M, Vayssade M, Dufresne M, Quéant S, Warocquier-Clérout R, Legeay G, Vigneron P, Olivier V, Duval JL, Nagel MD. Interactions of B16F10 melanoma cells aggregated on a cellulose substrate. J Cell Biochem 2006; 99:96-104. [PMID: 16598743 DOI: 10.1002/jcb.20833] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There is evidence that the shape of cells and their contact with a matrix direct the growth and the differentiation of both normal and cancer cells. Cells in 3D culture resemble the in vivo situation more closely than do those in conventional 2D cultures. We have studied the interactions and functions of B16F10 mouse melanoma cells, which spread and grow well on tissue culture polystyrene (tPS), when they were made to aggregate on cellulose-coated Petri dishes (CEL). This aggregation of melanoma cells on CEL was Ca2+ dependent and mediated by N-cadherins. The levels of N-cadherin and beta-catenin transcripts in cells cultured on CEL and tPS were similar, but those on CEL contained less beta-catenin protein. Immunoprecipitation and immunostaining showed that both N-cadherins and beta-catenins were present at the membranes of cells on CEL. Cells proliferated significantly more slowly after 48 h on CEL and the cellulose coating caused most of them to arrest in G1. We also compared the melanin contents and tyrosinase activity of cells on CEL and controls grown on tPS. Melanogenesis was induced in cells aggregated on CEL. A cellulose substrate thus appears to be an outstanding tool for studying cell-cell interactions and cell functions in 3D cultures.
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Affiliation(s)
- M Hindié
- Domaine Biomatériaux-Biocompatibilité, UMR CNRS 6600, Université de Technologie de Compiègne, BP20529 60205 Compiègne Cedex, France
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22
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Reginato MJ, Muthuswamy SK. Illuminating the center: mechanisms regulating lumen formation and maintenance in mammary morphogenesis. J Mammary Gland Biol Neoplasia 2006; 11:205-11. [PMID: 17115263 DOI: 10.1007/s10911-006-9030-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The lumens present in ductal structures are required for transport of fluids and air. Studies in model organisms and cells in culture suggest that lumens can be generated by multiple mechanisms including apoptosis of centrally located cells, and re-modeling of epithelia. Several studies point to a role for apoptosis during lumen formation in the mammary ducts. However, a role for other mechanisms during lumen formation in the mammary ducts is largely unexplored. Understanding how lumens are formed and maintained free of cells is of clinical importance because filling of the luminal space is associated with cancer and inflammation. Thus, further investigation can lead to new diagnostic and therapeutic opportunities.
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Affiliation(s)
- Mauricio J Reginato
- Department of Biochemistry and Molecular Biology, College of Medicine, Drexel University, 245 N. 15th Street, Philadelphia, PA 19102, USA.
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Obreztchikova M, Elouardighi H, Ho M, Wilson BA, Gertsberg Z, Steinberg SF. Distinct signaling functions for Shc isoforms in the heart. J Biol Chem 2006; 281:20197-204. [PMID: 16699171 PMCID: PMC1761690 DOI: 10.1074/jbc.m601859200] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Thrombin activates protease-activated receptor-1 (PAR-1) and engages signaling pathways that influence the growth and survival of cardiomyocytes as well as extracellular matrix remodeling by cardiac fibroblasts. This study examines the role of Shc proteins in PAR-1-dependent signaling pathways that influence ventricular remodeling. We show that thrombin increases p46Shc/p52Shc phosphorylation at Tyr(239)/Tyr(240) and Tyr(317) (and p66Shc-Ser(36) phosphorylation) via a pertussis toxin-insensitive epidermal growth factor receptor (EGFR) transactivation pathway in cardiac fibroblasts; p66Shc-Ser(36) phosphorylation is via a MEK-dependent mechanism. In contrast, cardiac fibroblasts express beta(2)-adrenergic receptors that activate ERK through a pertussis toxin-sensitive EGFR transactivation pathway that does not involve Shc isoforms or lead to p66Shc-Ser(36) phosphorylation. In cardiomyocytes, thrombin triggers MEK-dependent p66Shc-Ser(36) phosphorylation, but this is not via EGFR transactivation (or associated with Shc-Tyr(239)/Tyr(240) and/or Tyr(317) phosphorylation). Importantly, p66Shc protein expression is detected in neonatal, but not adult, cardiomyocytes; p66Shc expression is induced (via a mechanism that requires protein kinase C and MEK activity) by Pasteurella multocida toxin, a Galpha(q) agonist that promotes cardiomyocyte hypertrophy. These results identify novel regulation of individual Shc isoforms in receptor-dependent pathways leading to cardiac hypertrophy and the transition to heart failure. The observations that p66Shc expression is induced by a Galpha(q) agonist and that PAR-1 activation leads to p66Shc-Ser(36) phosphorylation identifies p66Shc as a novel candidate hypertrophy-induced mediator of cardiomyocyte apoptosis and heart failure.
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Affiliation(s)
- Maria Obreztchikova
- From the Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| | - Hasnae Elouardighi
- From the Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| | - Mengfei Ho
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Brenda A. Wilson
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Zoya Gertsberg
- From the Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| | - Susan F. Steinberg
- From the Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
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Ryer EJ, Sakakibara K, Wang C, Sarkar D, Fisher PB, Faries PL, Kent KC, Liu B. Protein kinase C delta induces apoptosis of vascular smooth muscle cells through induction of the tumor suppressor p53 by both p38-dependent and p38-independent mechanisms. J Biol Chem 2005; 280:35310-7. [PMID: 16118209 DOI: 10.1074/jbc.m507187200] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Apoptotic death of vascular smooth muscle cells (SMCs) is a prominent feature of blood vessel remodeling. In the present study, we examined the novel PKC isoform protein kinase C delta (PKCdelta) and its role in vascular SMC apoptosis. In A10 SMCs, overexpression of PKCdelta was sufficient to induce apoptosis, whereas inhibition of PKCdelta diminished H2O2-induced apoptosis. Moreover, evidence is provided that the tumor suppressor p53 is an essential mediator of PKCdelta-induced apoptosis in SMCs. Activation of PKCdelta led to accumulation as well as phosphorylation of p53 in SMCs; this induction correlated with apoptosis. Furthermore, blocking p53 induction with small interference RNA or targeted gene deletion prevented PKCdelta-induced apoptosis, whereas restoring p53 expression rescued the ability of PKCdelta to induce apoptosis in p53 null SMCs. We also establish that PKCdelta regulates p53 at both transcriptional and post-translational levels. Specifically, the transcriptional regulation required p38 MAPK, whereas the post-translational modification, at least for serine 46, did not involve MAPK. Additionally, PKCdelta, p38 MAPK, and p53 co-associate in cells under conditions favoring apoptosis. Together, our data suggest that SMC apoptosis proceeds through a pathway that involves PKCdelta, the intermediary p38 MAPK, and the downstream target tumor suppressor p53.
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Affiliation(s)
- Evan J Ryer
- Department of Surgery, Division of Vascular Surgery, New York Presbyterian Hospital and Weill Medical College, Cornell University, New York, New York 10021, USA
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