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Crowe A. Transcriptomic and western blot characterisation of the human CLEFF4 clone, a new rapid cell line replacement for the Caco2 model. Eur J Pharm Biopharm 2024; 199:114291. [PMID: 38641230 DOI: 10.1016/j.ejpb.2024.114291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 03/18/2024] [Accepted: 04/15/2024] [Indexed: 04/21/2024]
Abstract
The CLEFF4 sub clone from stock late passage Caco2 cells has a unique property of being able to develop polarised cell monolayers with high P-gp expression and tight junctions much quicker than the original cell line. Instead of being useful for transport studies 21-24 days after initiating culture, the CLEFF4 cell line matures in 5-6 days with tight junctions surpassing that of 3 week old Caco2 cells in that time frame [1]. This has enabled the CLEFF4 cell line to provide measures of apparent permeability for potential drug candidates, so important for pre-clinical drug development, 4 times faster than the original cell line. RNA samples were collected and analysed at days 4 and 7 of culture over a 3 year period and had full RNA transcriptome analysed by the ranaseq.eu open bioinformatics platform. Protein was also collected from day 4 to day 22 of culture. Differential expression data from the FASTQ files have shown significant differences in expression in multiple genes involved with drug efflux, tight junctions, phase 2 metabolism and growth factors, which have been confirmed from protein determination that may hold the key to understanding accelerated human cell maturation. These gene expression results may be significant for other tissues beyond the gastrointestinal tract, and potentially for accelerated cell growth for the new field of laboratory grown tissues for organ replacement. The data also confirms the different genetic expression in CLEFF4 cells compared to Caco2 and the stable nature of the different expression over many years.
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Affiliation(s)
- Andrew Crowe
- Curtin Medical School, Curtin University, Perth, WA, 6845 Australia; Curtin Health Innovation Research Institute (CHIRI), Curtin University, Perth, WA, 6845 Australia
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2
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da Fonseca IIM, Nagamine MK, Sato A, Rossatto-Jr CA, Yeh ES, Dagli MLZ. Inhibitory Effects of Alpha-Connexin Carboxyl-Terminal Peptide on Canine Mammary Epithelial Cells: A Study on Benign and Malignant Phenotypes. Cancers (Basel) 2024; 16:820. [PMID: 38398211 PMCID: PMC10887206 DOI: 10.3390/cancers16040820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/10/2024] [Accepted: 02/16/2024] [Indexed: 02/25/2024] Open
Abstract
Mammary cancer is highly prevalent in non-castrated female dogs. Cell-to-cell communication is an important mechanism to maintain homeostasis, and connexins are proteins that assemble to form the communicating gap junctions. In many cancers, communication capacity is reduced; several approaches are being tested in order to increase the communication capacity in cancer cells and, therefore, alter their viability. This study analyzed the effects of the alpha-connexin carboxyl-terminal peptide (αCT1) on canine mammary non-neoplastic and neoplastic epithelial cells. Seven canine epithelial mammary cell lines were used. Among these, one was a normal canine epithelial mammary cell line (LOEC-NMG), two canine mammary adenomas (LOEC-MAd1 and LOEC-MAd2), and four canine mammary adenocarcinomas (LOEC-MCA1, LOEC-MCA2, LOEC-MCA3 and CF41). The αCT1 corresponds to a short Cx43 C-terminal sequence linked to an internalization sequence called the antennapedia. After 24 h of incubation, the medium containing different αCT1 peptide concentrations was added to the cells, and only the culture medium was used for control. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used to quantify cell viability before treatment and 48, 72, and 96 h after the treatment. Results showed that the normal mammary epithelial cell line (LOEC-NMG) was resistant to treatment with αCT1, which is consistent with a previous study on human mammary cell lines. One of the adenoma cell lines (LOEC-MAd2) was also resistant to treatment with αCT1, although the other (LOEC-MAd1) was susceptible to treatment, mostly at 72 h after treatment. Regarding the four canine adenocarcinoma cell lines, they differ regarding the susceptibility to the treatment with αCT1. Three cell lines, canine mixed adenocarcinoma (LOEC-MCA1), canine complex adenocarcinoma (LOEC-MCA2), and commercial canine mammary adenocarcinoma cell line CF41, were susceptible to treatment with αCT1, while one canine mammary adenocarcinoma cell line (LOEC-MCA3) was resistant to treatment. In most αCT1 treated cell lines, Cx43 was strongly detected in cell membranes by immunofluorescence. We propose that αCT1 restored the cell-to-cell communication capacity of neoplastic cells and induced inhibitory effects on cell viability.
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Affiliation(s)
- Ivone Izabel Mackowiak da Fonseca
- Laboratory of Experimental and Comparative Oncology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo 05508-900, Brazil; (I.I.M.d.F.); (M.K.N.); (A.S.); (C.A.R.-J.)
| | - Marcia Kazumi Nagamine
- Laboratory of Experimental and Comparative Oncology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo 05508-900, Brazil; (I.I.M.d.F.); (M.K.N.); (A.S.); (C.A.R.-J.)
| | - Ayami Sato
- Laboratory of Experimental and Comparative Oncology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo 05508-900, Brazil; (I.I.M.d.F.); (M.K.N.); (A.S.); (C.A.R.-J.)
- Institute of Life Innovation Studies, Toyo University, Tokyo 374-0193, Japan
| | - Carlos Alberto Rossatto-Jr
- Laboratory of Experimental and Comparative Oncology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo 05508-900, Brazil; (I.I.M.d.F.); (M.K.N.); (A.S.); (C.A.R.-J.)
| | - Elizabeth Shinmay Yeh
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Melvin and Bren Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Maria Lucia Zaidan Dagli
- Laboratory of Experimental and Comparative Oncology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo 05508-900, Brazil; (I.I.M.d.F.); (M.K.N.); (A.S.); (C.A.R.-J.)
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3
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El-Hajjar L, Saliba J, Karam M, Shaito A, El Hajj H, El-Sabban M. Ubiquitin-Related Modifier 1 (URM-1) Modulates Cx43 in Breast Cancer Cell Lines. Int J Mol Sci 2023; 24:ijms24032958. [PMID: 36769280 PMCID: PMC9917400 DOI: 10.3390/ijms24032958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/23/2022] [Accepted: 12/28/2022] [Indexed: 02/05/2023] Open
Abstract
Gap-junction-forming connexins are exquisitely regulated by post-translational modifications (PTMs). In particular, the PTM of connexin 43 (Cx43), a tumor suppressor protein, regulates its turnover and activity. Here, we investigated the interaction of Cx43 with the ubiquitin-related modifier 1 (URM-1) protein and its impact on tumor progression in two breast cancer cell lines, highly metastatic triple-negative MDA-MB-231 and luminal breast cancer MCF-7 cell lines. To evaluate the subsequent modulation of Cx43 levels, URM-1 was downregulated in these cells. The transcriptional levels of epithelial-to-mesenchymal transition (EMT) markers and the metastatic phenotype were assessed. We demonstrated that Cx43 co-localizes and interacts with URM-1, and URMylated Cx43 was accentuated upon cellular stress. The significant upregulation of small ubiquitin-like modifier-1 (SUMO-1) was also observed. In cells with downregulated URM-1, Cx43 expression significantly decreased, and SUMOylation by SUMO-1 was affected. The concomitant expression of EMT markers increased, leading to increased proliferation, migration, and invasion potential. Inversely, the upregulation of URM-1 increased Cx43 expression and reversed EMT-induced processes, underpinning a role for this PTM in the observed phenotypes. This study proposes that the URMylation of Cx43 in breast cancer cells regulates its tumor suppression properties and contributes to breast cancer cell malignancy.
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Affiliation(s)
- Layal El-Hajjar
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut P.O. Box 11-0236, Lebanon
| | - Jessica Saliba
- Department of Biology, Faculty of Sciences, Lebanese University, Beirut P.O. Box 90656, Lebanon
- Department of Public Health, Faculty of Health Sciences, University of Balamand, Beirut P.O. Box 100, Lebanon
| | - Mario Karam
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut P.O. Box 11-0236, Lebanon
| | - Abdullah Shaito
- Biomedical Research Center, Qatar University Doha, Doha P.O. Box 2713, Qatar
| | - Hiba El Hajj
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut P.O. Box 11-0236, Lebanon
| | - Marwan El-Sabban
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut P.O. Box 11-0236, Lebanon
- Correspondence: ; Tel.: +961-(1)-350000 (ext. 4765)
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4
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Nunes B, Pópulo H, Lopes JM, Reis M, Nascimento G, Nascimento AG, Fernandes J, Faria M, de Carvalho DP, Soares P, Miranda-Alves L. Connexin Expression in Pituitary Adenomas and the Effects of Overexpression of Connexin 43 in Pituitary Tumor Cell Lines. Genes (Basel) 2022; 13:genes13040674. [PMID: 35456480 PMCID: PMC9032236 DOI: 10.3390/genes13040674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/22/2022] [Accepted: 04/06/2022] [Indexed: 01/27/2023] Open
Abstract
Gap junction intercellular communication (GJIC) is considered a key mechanism in the regulation of tissue homeostasis. GJIC structures are organized in two transmembrane channels, with each channel formed by connexins (Cxs). GJIC and Cxs expression alterations are related to the process of tumorigenesis in different cell types. Pituitary neuroendocrine tumors (PitNETs) represent 15–20% of intracranial neoplasms, and usually display benign behavior. Nevertheless, some may have aggressive behavior, invading adjacent tissues, and featuring a high proliferation rate. We aimed to assess the expression and relevance of GJIC and Cxs proteins in PitNETs. We evaluated the mRNA expression levels of Cx26, 32, and 43, and the protein expression of Cx43 in a series of PitNETs. In addition, we overexpressed Cx43 in pituitary tumor cell lines. At the mRNA level, we observed variable expression of all the connexins in the tumor samples. Cx43 protein expression was absent in most of the pituitary tumor samples that were studied. Moreover, in vitro studies revealed that the overexpression of Cx43 decreases cell growth and induces apoptosis in pituitary tumor cell lines. Our results indicate that the downregulation of Cx43 protein might be involved in the tumorigenesis of most pituitary adenomas and have a potential therapeutic value for pituitary tumor therapy.
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Affiliation(s)
- Bruno Nunes
- Laboratory of Experimental Endocrinology—LEEx, Institute of Biomedical Science, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (B.N.); (D.P.d.C.); (L.M.-A.)
- Postgraduate Program in Endocrinology, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Laboratory of Endocrine Physiology, Doris Rosenthal, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Helena Pópulo
- Institute for Research and Innovation in Health, University of Porto, 4200-135 Porto, Portugal; (H.P.); (J.M.L.); (M.R.)
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP)—Cancer Signalling & Metabolism, 4200-135 Porto, Portugal
- Department of Pathology, Medical Faculty of the University of Porto, 4200-319 Porto, Portugal
| | - José Manuel Lopes
- Institute for Research and Innovation in Health, University of Porto, 4200-135 Porto, Portugal; (H.P.); (J.M.L.); (M.R.)
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP)—Cancer Signalling & Metabolism, 4200-135 Porto, Portugal
- Department of Pathology, Medical Faculty of the University of Porto, 4200-319 Porto, Portugal
| | - Marta Reis
- Institute for Research and Innovation in Health, University of Porto, 4200-135 Porto, Portugal; (H.P.); (J.M.L.); (M.R.)
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP)—Cancer Signalling & Metabolism, 4200-135 Porto, Portugal
| | - Gilvan Nascimento
- Centre of Clinical Research (CEPEC), President Dutra Hospital of Federal University of Maranhão (UFMA), São Luís 65020-600, Brazil; (G.N.); (M.F.)
- Endocrinology Service, President Dutra Hospital of Federal University of Maranhão (UFMA), São Luís 65060-600, Brazil
| | - Ana Giselia Nascimento
- Pathology Service, President Dutra Hospital of Federal University of Maranhão (UFMA), São Luís 65020-070, Brazil;
| | - Janaína Fernandes
- NUPEX, Polo Duque de Caxias, Universidade Federal do Rio de Janeiro, Rio de Janeiro 25240-005, Brazil;
| | - Manuel Faria
- Centre of Clinical Research (CEPEC), President Dutra Hospital of Federal University of Maranhão (UFMA), São Luís 65020-600, Brazil; (G.N.); (M.F.)
- Endocrinology Service, President Dutra Hospital of Federal University of Maranhão (UFMA), São Luís 65060-600, Brazil
| | - Denise Pires de Carvalho
- Laboratory of Experimental Endocrinology—LEEx, Institute of Biomedical Science, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (B.N.); (D.P.d.C.); (L.M.-A.)
- Postgraduate Program in Endocrinology, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Laboratory of Endocrine Physiology, Doris Rosenthal, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Paula Soares
- Institute for Research and Innovation in Health, University of Porto, 4200-135 Porto, Portugal; (H.P.); (J.M.L.); (M.R.)
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP)—Cancer Signalling & Metabolism, 4200-135 Porto, Portugal
- Department of Pathology, Medical Faculty of the University of Porto, 4200-319 Porto, Portugal
- Correspondence:
| | - Leandro Miranda-Alves
- Laboratory of Experimental Endocrinology—LEEx, Institute of Biomedical Science, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (B.N.); (D.P.d.C.); (L.M.-A.)
- Postgraduate Program in Endocrinology, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Laboratory of Endocrine Physiology, Doris Rosenthal, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Postgraduate Program in Pharmacology and Medicinal Chemistry, Institute of Biomedical Science, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
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5
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Unal YC, Yavuz B, Ozcivici E, Mese G. The role of connexins in breast cancer: from misregulated cell communication to aberrant intracellular signaling. Tissue Barriers 2021; 10:1962698. [PMID: 34355641 DOI: 10.1080/21688370.2021.1962698] [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: 12/24/2022] Open
Abstract
In spite of clinical advancements and improved diagnostic techniques, breast cancers are the leading cause of cancer-associated deaths in women worldwide. Although 70% of early breast cancers can be cured, there are no efficient therapies against metastatic breast cancers. Several factors including connexins and gap junctions play roles in breast tumorigenesis. Connexins are critical for cellular processes as a linkage between connexin mutations and hereditary disorders demonstrated their importance for tissue homeostasis. Further, alterations in their expression, localization and channel activities were observed in many cancers including breast cancer. Both channel-dependent and independent functions of connexins were reported in initiation and progression of cancers. Unlike initial reports suggesting tumor suppressor functions, connexins and gap junctions have stage, context and isoform dependent effects in breast cancers similar to other cancers. In this review, we tried to describe the current understanding of connexins in tumorigenesis specifically in breast cancers.
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Affiliation(s)
- Yagmur Ceren Unal
- Faculty of Science, Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Busra Yavuz
- Faculty of Science, Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Engin Ozcivici
- Department of Bioengineering, Faculty of Engineering, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Gulistan Mese
- Faculty of Science, Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey
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6
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Glucose-limiting conditions induce an invasive population of MDA-MB-231 breast cancer cells with increased connexin 43 expression and membrane localization. J Cell Commun Signal 2021; 15:223-236. [PMID: 33591483 PMCID: PMC7991056 DOI: 10.1007/s12079-020-00601-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 12/09/2020] [Indexed: 01/10/2023] Open
Abstract
Gap junctional intercellular communication (GJIC) is a homeostatic process mediated by membrane channels composed of a protein family known as connexins. Alterations to channel activity can modulate suppression or facilitation of cancer progression. These varying roles are influenced by the cancer cell genetic profile and the context-dependent mechanisms of a dynamic extracellular environment that encompasses fluctuations to nutrient availability. To better explore the effects of altered cellular metabolism on GJIC in breast cancer, we generated a derivative of the triple-negative breast cancer cell line MDA-MB-231 optimized for growth in low-glucose. Reduced availability of glucose is commonly encountered during tumor development and leads to metabolic reprogramming in cancer cells. MDA-MB-231 low-glucose adapted cells exhibited a larger size with improved cell–cell contact and upregulation of cadherin-11. Additionally, increased protein levels of connexin 43 and greater plasma membrane localization were observed with a corresponding improvement in GJIC activity compared to the parental cell line. Since GJIC has been shown to affect cellular invasion in multiple cancer cell types, we evaluated the invasive qualities of these cells using multiple three-dimensional Matrigel growth models. Results of these experiments demonstrated a significantly more invasive phenotype. Moreover, a decrease in invasion was noted when GJIC was inhibited. Our results indicate a potential response of triple-negative breast cancer cells to reduced glucose availability that results in changes to GJIC and invasiveness. Delineation of this relationship may help elucidate mechanisms by which altered cancer cell metabolism affects GJIC and how cancer cells respond to nutrient availability in this regard.
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7
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Van Campenhout R, Cooreman A, Leroy K, Rusiecka OM, Van Brantegem P, Annaert P, Muyldermans S, Devoogdt N, Cogliati B, Kwak BR, Vinken M. Non-canonical roles of connexins. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 153:35-41. [PMID: 32220599 DOI: 10.1016/j.pbiomolbio.2020.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/06/2020] [Accepted: 03/16/2020] [Indexed: 12/12/2022]
Abstract
Gap junctions mediate cellular communication and homeostasis by controlling the intercellular exchange of small and hydrophilic molecules and ions. Gap junction channels are formed by the docking of 2 hemichannels of adjacent cells, which in turn are composed of 6 connexin subunits. Connexin proteins as such can also control the cellular life cycle independent of their channel activities. This has been most demonstrated in the context of cell growth and cell death. Different mechanisms are involved mainly related to direct interaction with cell growth or cell death regulators, but also implying effects on the expression of cell growth and cell death regulators. The present paper focuses on these atypical roles of connexin proteins.
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Affiliation(s)
- Raf Van Campenhout
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Axelle Cooreman
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kaat Leroy
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Olga M Rusiecka
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Pieter Van Brantegem
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Pieter Annaert
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Serge Muyldermans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Nick Devoogdt
- In Vivo Cellular and Molecular Imaging Laboratory, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
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8
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Gouesse RJ, Lavoie M, Dianati E, Wade MG, Hales BF, Robaire B, Plante I. Gestational and Lactational Exposure to an Environmentally Relevant Mixture of Brominated Flame Retardants Downregulates Junctional Proteins, Thyroid Hormone Receptor α1 Expression, and the Proliferation-Apoptosis Balance in Mammary Glands Post Puberty. Toxicol Sci 2019; 171:13-31. [PMID: 31241157 PMCID: PMC6735962 DOI: 10.1093/toxsci/kfz147] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/11/2019] [Accepted: 06/11/2019] [Indexed: 12/21/2022] Open
Abstract
Mammary gland development requires hormonal regulation during puberty, pregnancy, and lactation. Brominated flame retardants (BFRs) are endocrine disruptors; they are added to consumer products to satisfy flammability standards. Previously, we showed that gestational and lactational exposure to an environmentally relevant mixture of BFRs disrupts proteins of the adherens junctions in rat dam mammary glands at weaning. Here, we hypothesize that perinatal exposure to the same BFR mixture also disrupts junctional proteins and signaling pathways controlling mammary gland development in pups. Dams were exposed through diet to a BFR mixture based on the substances in house dust; doses of the mixture used were 0, 0.06, 20, or 60 mg/kg/day. Dams were exposed continuously beginning prior to mating until pups' weaning; female offspring were euthanized on postnatal day (PND) 21, 46, and 208. The lowest dose of BFRs significantly downregulated adherens junction proteins, E-cadherin, and β-catenin, and the gap junction protein p-Cx43, as well as thyroid hormone receptor alpha 1 protein at PND 46. No effects were observed on estrogen or progesterone receptors. The low dose also resulted in a decrease in cleaved caspase-3, a downward trend in PARP levels, proteins involved in apoptosis, and an upward trend in proliferating cell nuclear antigen, a marker of proliferation. No effects were observed on ductal elongation or on the numbers of terminal end buds. Together, our results indicate that gestational and lactational exposure to an environmentally relevant mixture of BFRs disrupts cell-cell interactions, thyroid hormone homeostasis and the proliferation-apoptosis balance at PND 46, a critical stage for mammary gland development.
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Affiliation(s)
| | - Mélanie Lavoie
- INRS, Centre Armand-Frappier Santé Bioscience, Laval, Quebec, Canada
| | - Elham Dianati
- INRS, Centre Armand-Frappier Santé Bioscience, Laval, Quebec, Canada
| | - Mike G Wade
- Health Canada, Environmental Health Science and Research Bureau, Ottawa, Ontario, Canada
| | | | - Bernard Robaire
- Department of Pharmacology & Therapeutics
- Department of Obstetrics & Gynecology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Isabelle Plante
- INRS, Centre Armand-Frappier Santé Bioscience, Laval, Quebec, Canada
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9
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Naser Al Deen N, AbouHaidar M, Talhouk R. Connexin43 as a Tumor Suppressor: Proposed Connexin43 mRNA-circularRNAs-microRNAs Axis Towards Prevention and Early Detection in Breast Cancer. Front Med (Lausanne) 2019; 6:192. [PMID: 31555649 PMCID: PMC6724403 DOI: 10.3389/fmed.2019.00192] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/14/2019] [Indexed: 01/04/2023] Open
Abstract
Breast cancer (BC) is a global public health burden, constituting the highest cancer incidence in women worldwide. Connexin43 (Cx43) is a member of a family of transmembrane proteins responsible in part for intercellular communication between adjacent breast epithelial cells, via gap junctions. Cx43 plays key role in mammary gland development and differentiation and its spatio-temporal perturbation contributes to tumorigenesis. Thus, Cx43 acts as a breast tumor-suppressor. Signaling pathways and phenotypes downstream of Cx43 mRNA loss/mis-localization in breast cells have been well-studied. However, axes parallel to Cx43 loss are less understood. microRNAs (miRNAs) are small endogenous non-coding RNAs that repress translation and circularRNAs (circRNAs) are a class of endogenous RNAs that originate from RNA splicing and act as miRNA "sponges". CircRNAs and miRNAs are dysregulated in cancers and are highly abundant and stable in the circulation. Thus, they present as attractive liquid biopsy cancer biomarkers. Here, an axis for Cx43 mRNA-circRNAs-miRNAs interactions along BC initiation (denoted by loss of breast epithelial polarity and development of hyperplastic phenotypes) is proposed to potentially serve as a signature biomarker toward BC early-onset detection and prevention.
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Affiliation(s)
- Nataly Naser Al Deen
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
| | - Mounir AbouHaidar
- Department of Cell and Systems Biology, Faculty of Arts and Sciences, University of Toronto, Toronto, ON, Canada
| | - Rabih Talhouk
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
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10
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Hou X, Khan MRA, Turmaine M, Thrasivoulou C, Becker DL, Ahmed A. Wnt signaling regulates cytosolic translocation of connexin 43. Am J Physiol Regul Integr Comp Physiol 2019; 317:R248-R261. [DOI: 10.1152/ajpregu.00268.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The availability of intracellular, stabilized β-catenin, a transcription factor coactivator, is tightly regulated; β-catenin is translocated into the nucleus in response to Wnt ligand binding to its cell membrane receptors. Here we show that Wnt signal activation in mammalian cells activates intracellular mobilization of connexin 43 (Cx43), which belongs to a gap junction protein family, a new target protein in response to extracellular Wnt signal activation. Transmission electron microscopy showed that the nuclear localization of Cx43 was increased by 8- to 10-fold in Wnt5A- and 9B-treated cells compared with controls; this Wnt-induced increase was negated in the cells where Cx43 and β-catenin were knocked down using shRNA. There was a significant ( P < 0.001) and concomitant depletion of the cell membrane and cytosolic signal of Cx43 in Wnt-treated cells with an increase in the nuclear signal for Cx43; this was more obvious in cells where β-catenin was knocked down using shRNA. Conversely, Cx43 knockdown resulted in increased β-catenin in the nucleus in the absence of Wnt activation. Coimmunoprecipitation of Cx43 and β-catenin proteins with a casein kinase (CKIδ) antibody showed that Cx43 interacts with β-catenin and may form part of the so-called destruction complex. Functionally, Wnt activation increased the rate of wound reepithelization in rat skin in vivo.
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Affiliation(s)
- Xiaoming Hou
- Prostate Cancer Research Centre, Division of Surgery, University College London, London, United Kingdom
- Research Department of Cell and Developmental Biology, The Centre for Cell and Molecular Dynamics, University College London, London, United Kingdom
| | - Mohammad R. A. Khan
- Prostate Cancer Research Centre at the Centre for Stem Cells and Regenerative Medicine, King's College London, Guy's Hospital, London, United Kingdom
| | - Mark Turmaine
- Division of Biosciences, University College London, London, United Kingdom
| | - Christopher Thrasivoulou
- Research Department of Cell and Developmental Biology, The Centre for Cell and Molecular Dynamics, University College London, London, United Kingdom
| | - David L Becker
- Research Department of Cell and Developmental Biology, The Centre for Cell and Molecular Dynamics, University College London, London, United Kingdom
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Institute of Medical Biology, A*STAR, Singapore
| | - Aamir Ahmed
- Prostate Cancer Research Centre, Division of Surgery, University College London, London, United Kingdom
- Prostate Cancer Research Centre at the Centre for Stem Cells and Regenerative Medicine, King's College London, Guy's Hospital, London, United Kingdom
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11
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Bazzoun D, Adissu HA, Wang L, Urazaev A, Tenvooren I, Fostok SF, Chittiboyina S, Sturgis J, Hodges K, Chandramouly G, Vidi PA, Talhouk RS, Lelièvre SA. Connexin 43 maintains tissue polarity and regulates mitotic spindle orientation in the breast epithelium. J Cell Sci 2019; 132:jcs.223313. [PMID: 30992345 DOI: 10.1242/jcs.223313] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 04/08/2019] [Indexed: 12/11/2022] Open
Abstract
Cell-cell communication is essential for tissue homeostasis, but its contribution to disease prevention remains to be understood. We demonstrate the involvement of connexin 43 (Cx43, also known as GJA1) and related gap junction in epithelial homeostasis, illustrated by polarity-mediated cell cycle entry and mitotic spindle orientation (MSO). Cx43 localization is restricted to the apicolateral membrane of phenotypically normal breast luminal epithelial cells in 3D culture and in vivo Chemically induced blockade of gap junction intercellular communication (GJIC), as well as the absence of Cx43, disrupt the apicolateral distribution of polarity determinant tight junction marker ZO-1 (also known as TJP1) and lead to random MSO and cell multilayering. Induced expression of Cx43 in cells that normally lack this protein reestablishes polarity and proper MSO in 3D culture. Cx43-directed MSO implicates PI3K-aPKC signaling, and Cx43 co-precipitates with signaling node proteins β-catenin (CTNNB1) and ZO-2 (also known as TJP2) in the polarized epithelium. The distribution of Cx43 is altered by pro-inflammatory breast cancer risk factors such as leptin and high-fat diet, as shown in cell culture and on tissue biopsy sections. The control of polarity-mediated quiescence and MSO may contribute to the tumor-suppressive role of Cx43.
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Affiliation(s)
- D Bazzoun
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA.,Biology Department, Faculty of Arts and Sciences, American University of Beirut, 11-0236 Beirut, Lebanon
| | - H A Adissu
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - L Wang
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - A Urazaev
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - I Tenvooren
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - S F Fostok
- Biology Department, Faculty of Arts and Sciences, American University of Beirut, 11-0236 Beirut, Lebanon
| | - S Chittiboyina
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - J Sturgis
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - K Hodges
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - G Chandramouly
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - P-A Vidi
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - R S Talhouk
- Biology Department, Faculty of Arts and Sciences, American University of Beirut, 11-0236 Beirut, Lebanon
| | - S A Lelièvre
- Basic Medical Sciences, Purdue University, West Lafayette, IN 47907, USA .,Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA
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12
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Cx43 Expression Correlates with Breast Cancer Metastasis in MDA-MB-231 Cells In Vitro, In a Mouse Xenograft Model and in Human Breast Cancer Tissues. Cancers (Basel) 2019; 11:cancers11040460. [PMID: 30939738 PMCID: PMC6521103 DOI: 10.3390/cancers11040460] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/22/2019] [Accepted: 02/27/2019] [Indexed: 12/13/2022] Open
Abstract
Connexins regulate multiple cellular functions and are considered tumor suppressors. Connexin43 (Cx43) is frequently down-regulated in breast tumors. However, Cx43 regulation during cancer onset and metastasis is complex and context-dependent. We investigated the effect of Cx43 over-expression or knock-down on the metastatic potential of MDA-MB-231 breast cancer cells in vitro and in vivo and in human breast cancer tissues. MDA-MB-231 cells over-expressing (Cx43D) or down-regulating Cx43 (shCx43) were generated and used in proliferation, migration, and invasion assays. The regulation of genes/proteins implicated in progression, invasion and metastasis was assessed in vitro and in immune-compromized mice injected with MDA-MB-231, Cx43D or shCx43 cells. Primary tumor onset/growth, metastasis and overall survival of these animals was monitored and evaluated. In addition, Cx43 expression in human breast carcinoma samples was assessed by qPCR. Cx43 over-expression increased protein levels of epithelial markers E-cadherin and zonula occludens 1 expression and resulted in the sequestration of β-catenin at the cell membrane, while Cx43 knock-down induced protein expression of the mesenchymal marker N-cadherin and an increased invasive potential of shCx43 cells. In vivo, in mice xenografted with breast cancer cells, Cx43 over-expression decreased tumor volume, attenuated cell metastasis to lungs and liver and increased overall mice survival. Importantly, the expression of Cx43 in triple negative human breast cancer tissues is also down-regulated. Collectively, Cx43 over-expression induced an epithelial-like phenotype in MDA-MB-231 cells and suppressed tumor growth and metastasis to secondary organs in vivo. In contrast, Cx43 knock-down in MDA-MB-231 cells induced a mesenchymal phenotype with increased cell invasion leading to an enhanced metastatic phenotype. These data provide evidence for a pivotal role of Cx43 in breast cancer metastasis and support the potential targeting of connexins in breast cancer therapy.
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13
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Connexin 43 Loss Triggers Cell Cycle Entry and Invasion in Non-Neoplastic Breast Epithelium: A Role for Noncanonical Wnt Signaling. Cancers (Basel) 2019; 11:cancers11030339. [PMID: 30857262 PMCID: PMC6468895 DOI: 10.3390/cancers11030339] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 02/15/2019] [Accepted: 03/04/2019] [Indexed: 12/26/2022] Open
Abstract
(1) Background: The expression of connexin 43 (Cx43) is disrupted in breast cancer, and re-expression of this protein in human breast cancer cell lines leads to decreased proliferation and invasiveness, suggesting a tumor suppressive role. This study aims to investigate the role of Cx43 in proliferation and invasion starting from non-neoplastic breast epithelium. (2) Methods: Nontumorigenic human mammary epithelial HMT-3522 S1 cells and Cx43 shRNA-transfected counterparts were cultured under 2-dimensional (2-D) and 3-D conditions. (3) Results: Silencing Cx43 induced mislocalization of β-catenin and Scrib from apicolateral membrane domains in glandular structures or acini formed in 3-D culture, suggesting the loss of apical polarity. Cell cycle entry and proliferation were enhanced, concomitantly with c-Myc and cyclin D1 upregulation, while no detectable activation of Wnt/β-catenin signaling was observed. Motility and invasion were also triggered and were associated with altered acinar morphology and activation of ERK1/2 and Rho GTPase signaling, which acts downstream of the noncanonical Wnt pathway. The invasion of Cx43-shRNA S1 cells was observed only under permissive stiffness of the extracellular matrix (ECM). (4) Conclusion: Our results suggest that Cx43 controls proliferation and invasion in the normal mammary epithelium in part by regulating noncanonical Wnt signaling.
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14
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Fostok SF, El-Sibai M, El-Sabban M, Talhouk RS. Gap Junctions and Wnt Signaling in the Mammary Gland: a Cross-Talk? J Mammary Gland Biol Neoplasia 2019; 24:17-38. [PMID: 30194659 DOI: 10.1007/s10911-018-9411-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 09/03/2018] [Indexed: 12/21/2022] Open
Abstract
Connexins (Cxs), the building blocks of gap junctions (GJs), exhibit spatiotemporal patterns of expression and regulate the development and differentiation of the mammary gland, acting via channel-dependent and channel-independent mechanisms. Impaired Cx expression and localization are reported in breast cancer, suggesting a tumor suppressive role for Cxs. The signaling events that mediate the role of GJs in the development and tumorigenesis of the mammary gland remain poorly identified. The Wnt pathways, encompassing the canonical or the Wnt/β-catenin pathway and the noncanonical β-catenin-independent pathway, also play important roles in those processes. Indeed, aberrant Wnt signaling is associated with breast cancer. Despite the coincident roles of Cxs and Wnt pathways, the cross-talk in the breast tissue is poorly defined, although this is reported in a number of other tissues. Our previous studies revealed a channel-independent role for Cx43 in inducing differentiation or suppressing tumorigenesis of mammary epithelial cells by acting as a negative regulator of the Wnt/β-catenin pathway. Here, we provide a brief overview of mammary gland development, with emphasis on the role of Cxs in development and tumorigenesis of this tissue. We also discuss the role of Wnt signaling in similar contexts, and review the literature illustrating interplay between Cxs and Wnt pathways.
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Affiliation(s)
- Sabreen F Fostok
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut (AUB), P.O. Box: 11-0236, Beirut, Lebanon
| | - Mirvat El-Sibai
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University (LAU), Beirut, Lebanon
| | - Marwan El-Sabban
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut (AUB), Beirut, Lebanon
| | - Rabih S Talhouk
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut (AUB), P.O. Box: 11-0236, Beirut, Lebanon.
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15
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Wagner MS, Schultze E, Oliveira TL, de Leon PMM, Thurow HS, Campos VF, Oliveira I, de Souza D, Rodrigues OED, Collares T, Seixas FK. Revitalizing the AZT Through of the Selenium: An Approach in Human Triple Negative Breast Cancer Cell Line. Front Oncol 2018; 8:525. [PMID: 30524958 PMCID: PMC6262369 DOI: 10.3389/fonc.2018.00525] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 10/26/2018] [Indexed: 02/05/2023] Open
Abstract
Triple-negative breast cancer represents about 15% of all cases of breast cancer, and still represents a therapeutic challenge. 3′-Azido-3′-deoxythymidine (AZT) is a nucleoside reverse transcriptase inhibitor with antitumor activity. Chalcogenides compounds, such as selenium, are very important intermediates applied in organic synthesis. Our objective was to investigate the effect and the underlying cell death mechanisms of AZT and its derivatives, in human breast cancer cell lines. The inhibitory effect of AZT and derivatives (1072, 1073, and 1079) was determined by MTT assay (0.1, 1, 10, 50, and 100 μM for concentrations and times 4, 24, 48, and 72 h) and Live/Dead in tumor cell lines MCF-7, MDA-MB 231 and also in non-tumor cell line CHO. Gene expression profiles related to apoptosis were investigated by qRT-PCR and induction of apoptosis was investigated by flow cytometry. MTT and Live/Dead assays showed that AZT derivatives decreased the rate of cell proliferation at concentrations of 50 and 100 μM in tumor cell lines MCF-7 and MDA-MB 231 while the commercial AZT presented a low antitumoral potential in all strains tested. In flow cytometry analysis we demonstrated that derivatives of AZT induced apoptosis, with an increase in both initial and late stages in both tumor cell lines evaluated, especially in MDA-MB 231. Our data show that the AZT derivative 1072 increased the expression of transcripts of the genes caspase 3 and 8 in MDA-MB 231 cell line when compared to control, suggesting that the extrinsic pathway of apoptosis was activated. In conclusion, derivatives of AZT, especially 1072, induce cytotoxicity in vitro in the triple negative breast cancer cell line through activation of the extrinsic pathway of apoptosis. These compounds containing selenium in its formulation are potential therapeutic agents for breast cancer.
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Affiliation(s)
- Mônica Silveira Wagner
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Eduarda Schultze
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Thais Larre Oliveira
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Priscila Marques Moura de Leon
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Helena Strelow Thurow
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Vinicius Farias Campos
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Isabel Oliveira
- Departamento de Fisiologia e Farmacologia, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Diego de Souza
- LabSelen-NanoBio - Universidade de Federal de Santa Maria, Santa Maria, Brazil
| | | | - Tiago Collares
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
| | - Fabiana Kömmling Seixas
- Programa de Pós-Graduação em Biotecnologia, Grupo de Pesquisa em Oncologia Celular e Molecular, Biotecnologia/Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil
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16
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Kareh M, El Nahas R, Al-Aaraj L, Al-Ghadban S, Naser Al Deen N, Saliba N, El-Sabban M, Talhouk R. Anti-proliferative and anti-inflammatory activities of the sea cucumber Holothuria polii aqueous extract. SAGE Open Med 2018; 6:2050312118809541. [PMID: 30455947 PMCID: PMC6236865 DOI: 10.1177/2050312118809541] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 10/03/2018] [Indexed: 01/03/2023] Open
Abstract
Objective: Sea cucumbers are considered among the most important functional foods.
Following bioassay guided fractionation, we assessed the anti-proliferative
and anti-inflammatory activities of Holothuria polii
(H. polii) extracts. Methods: Sea cucumber ethanolic extract and the partially purified aqueous fractions
were assessed for their anti-proliferative activities. These latter
bioactivities were evaluated in the highly invasive MDA-MB-231 human breast
cancer cells in two-dimensional and three-dimensional cultures using trypan
blue exclusion assay. The tumor-suppressive effects of sea cucumber
ethanolic extract and aqueous fractions were assayed by measuring the
trans-well invasion of MDA-MB-231 cells and the expression of some
epithelial mesenchymal transition markers using quantitative
reverse-transcription polymerase chain reaction and western blot analysis.
The anti-inflammatory activity of the aqueous fraction was tested by
measuring the secreted levels of interleukin-6, nitric oxide, and matrix
metalloproteinase 9 in endotoxin-induced mammary epithelial SCp2 cells and
interleukin-1β in phorbol-12-myristate-13-acetate-activated human monocytic
THP-1 cells. Results: Sea cucumber ethanolic extract and the aqueous fraction significantly
decreased the proliferation of MDA-MB-231 cells by more than 50% at similar
and noncytotoxic concentrations and caused an arrest in the S-phase of the
cell cycle of treated cells. In contrast, petroleum ether, chloroform, ethyl
acetate, and n-butanol organic fractions did not show any
significant activity. Furthermore, sea cucumber ethanolic extract and
aqueous fraction reduced the proliferation of MDA-MB-231 cells in
three-dimensional cultures by more than 60% at noncytotoxic concentrations.
In addition, treatment with these concentrations resulted in the loss of
stellate outgrowths in favor of spherical aggregates and a 30% decrease in
invasive properties. Both sea cucumber ethanolic extract and aqueous
decreased the transcription of vimentin and the protein expression levels of
vimentin and N-cadherin in three-dimensional cultures. The aqueous fraction
decreased the levels of inflammatory markers interleukin-6, nitric oxide,
and matrix metalloproteinase 9 in the mouse mammary SCp2 cells, and the
level of interleukin-1β produced by
phorbol-12-myristate-13-acetate-activated THP-1 human monocytic cells. Conclusion: The data reveal for the first time promising anti-proliferative and
anti-inflammatory activities in H. polii water extract in
two-dimensional and three-dimensional culture models.
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Affiliation(s)
- Mike Kareh
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon.,Nature Conservation Center, American University of Beirut, Beirut, Lebanon
| | - Rana El Nahas
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon.,Nature Conservation Center, American University of Beirut, Beirut, Lebanon
| | - Lamis Al-Aaraj
- Nature Conservation Center, American University of Beirut, Beirut, Lebanon.,Department of Chemistry, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
| | - Sara Al-Ghadban
- Nature Conservation Center, American University of Beirut, Beirut, Lebanon.,Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Nataly Naser Al Deen
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
| | - Najat Saliba
- Nature Conservation Center, American University of Beirut, Beirut, Lebanon.,Department of Chemistry, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
| | - Marwan El-Sabban
- Nature Conservation Center, American University of Beirut, Beirut, Lebanon.,Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Rabih Talhouk
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon.,Nature Conservation Center, American University of Beirut, Beirut, Lebanon
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17
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Spagnol G, Trease AJ, Zheng L, Gutierrez M, Basu I, Sarmiento C, Moore G, Cervantes M, Sorgen PL. Connexin43 Carboxyl-Terminal Domain Directly Interacts with β-Catenin. Int J Mol Sci 2018; 19:ijms19061562. [PMID: 29882937 PMCID: PMC6032326 DOI: 10.3390/ijms19061562] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/18/2018] [Accepted: 05/22/2018] [Indexed: 12/13/2022] Open
Abstract
Activation of Wnt signaling induces Connexin43 (Cx43) expression via the transcriptional activity of β-catenin, and results in the enhanced accumulation of the Cx43 protein and the formation of gap junction channels. In response to Wnt signaling, β-catenin co-localizes with the Cx43 protein itself as part of a complex at the gap junction plaque. Work from several labs have also shown indirect evidence of this interaction via reciprocal co-immunoprecipitation. Our goal for the current study was to identify whether β-catenin directly interacts with Cx43, and if so, the location of that direct interaction. Identifying residues involved in direct protein⁻protein interaction is of importance when they are correlated to the phosphorylation of Cx43, as phosphorylation can modify the binding affinities of Cx43 regulatory protein partners. Therefore, combining the location of a protein partner interaction on Cx43 along with the phosphorylation pattern under different homeostatic and pathological conditions will be crucial information for any potential therapeutic intervention. Here, we identified that β-catenin directly interacts with the Cx43 carboxyl-terminal domain, and that this interaction would be inhibited by the Src phosphorylation of Cx43CT residues Y265 and Y313.
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Affiliation(s)
- Gaelle Spagnol
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Andrew J Trease
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Li Zheng
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Mirtha Gutierrez
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Ishika Basu
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Cleofes Sarmiento
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Gabriella Moore
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Matthew Cervantes
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Paul L Sorgen
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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18
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Ferrati S, Gadok AK, Brunaugh AD, Zhao C, Heersema LA, Smyth HDC, Stachowiak JC. Connexin membrane materials as potent inhibitors of breast cancer cell migration. J R Soc Interface 2018; 14:rsif.2017.0313. [PMID: 28768882 DOI: 10.1098/rsif.2017.0313] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/10/2017] [Indexed: 02/06/2023] Open
Abstract
Gap junction (GJ) channels facilitate cell-cell communication through the exchange of chemical and mechanical signals, ensuring proper tissue development and homeostasis. The complex, disease stage-dependent role of connexins in breast cancer progression has been extensively studied over the past two decades. In the early stages of breast cancer, substantial evidence supports the role of GJ channels, formed by connexins at the interfaces between neighbouring cells, as suppressors of cell migration and proliferation. These findings suggest that materials that reintroduce connexins into the tumour cell environment have the potential to inhibit cell migration. Here, we report that exposure of highly metastatic MDA-MB-231 breast tumour cells to connexin-rich biovesicle materials potently suppresses cell migration. Specifically, these biovesicles, which can form GJ interfaces with cells, were extracted from the plasma membrane of donor cells engineered to express a high concentration of functional connexin 43 channels. These connexin-rich membrane materials dramatically reduced cell migration in both a transwell migration assay and a scratch closure assay. Collectively, these results suggest that using membrane materials to reintroduce connexins into the tumour cell environment provides a novel approach for combating cell migration and invasion.
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Affiliation(s)
- Silvia Ferrati
- Division of Pharmaceutics, The University of Texas at Austin, 2409 University Ave, Austin, TX 78712, USA
| | - Avinash K Gadok
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W Dean Keeton Street, Austin, TX 78712, USA
| | - Ashlee D Brunaugh
- Division of Pharmaceutics, The University of Texas at Austin, 2409 University Ave, Austin, TX 78712, USA
| | - Chi Zhao
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W Dean Keeton Street, Austin, TX 78712, USA
| | - Lara A Heersema
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W Dean Keeton Street, Austin, TX 78712, USA
| | - Hugh D C Smyth
- Division of Pharmaceutics, The University of Texas at Austin, 2409 University Ave, Austin, TX 78712, USA
| | - Jeanne C Stachowiak
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W Dean Keeton Street, Austin, TX 78712, USA
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19
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Abstract
Purpose of Review Considerable progress has been made in the field of stem cell research; nonetheless, the use of stem cells for regenerative medicine therapies, for either endogenous tissue repair or cellular grafts post injury, remains a challenge. To better understand how to maintain stem cell potential in vivo and promote differentiation ex vivo, it is fundamentally important to elucidate the interactions between stem cells and their surrounding partners within their distinct niches. Recent Findings Among the vast array of proteins depicted as mediators for cell-to-cell interactions, connexin-comprised gap junctions play pivotal roles in the regulation of stem cell fate both in vivo and in vitro. Summary This review summarizes and illustrates the current knowledge regarding the multifaceted roles of Cx43, specifically, in various stem cell niches.
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Affiliation(s)
- Nafiisha Genet
- Department of Medicine, Genetics and Biomedical Engineering, Yale Cardiovascular Research Center, Vascular Biology Therapeutics Program, New Haven, USA.,2Yale Stem Cell Center Yale University School of Medicine, 300 George St, New Haven, CT 06511 USA
| | - Neha Bhatt
- Department of Medicine, Genetics and Biomedical Engineering, Yale Cardiovascular Research Center, Vascular Biology Therapeutics Program, New Haven, USA.,2Yale Stem Cell Center Yale University School of Medicine, 300 George St, New Haven, CT 06511 USA
| | - Antonin Bourdieu
- Department of Medicine, Genetics and Biomedical Engineering, Yale Cardiovascular Research Center, Vascular Biology Therapeutics Program, New Haven, USA.,2Yale Stem Cell Center Yale University School of Medicine, 300 George St, New Haven, CT 06511 USA
| | - Karen K Hirschi
- Department of Medicine, Genetics and Biomedical Engineering, Yale Cardiovascular Research Center, Vascular Biology Therapeutics Program, New Haven, USA.,2Yale Stem Cell Center Yale University School of Medicine, 300 George St, New Haven, CT 06511 USA
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20
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Amith SR, Wilkinson JM, Fliegel L. Na+/H+ exchanger NHE1 regulation modulates metastatic potential and epithelial-mesenchymal transition of triple-negative breast cancer cells. Oncotarget 2018; 7:21091-113. [PMID: 27049728 PMCID: PMC5008271 DOI: 10.18632/oncotarget.8520] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 03/24/2016] [Indexed: 12/20/2022] Open
Abstract
In triple-negative breast cancer (TNBC), the high recurrence rate, increased invasion and aggressive metastatic formation dictate patient survival. We previously demonstrated a critical role for the Na+/H+ exchanger isoform 1 (NHE1) in controlling metastasis of triple-negative cells. Here, we investigated the effect of changes to three regulatory loci of NHE1. Two via the Ras/Raf/ERK/p90RSK pathway: p90RSK/14-3-3 (S703A) and ERK1/2 (S766,770,771A, SSSA) and a third via a calmodulin-binding domain (K641,R643,645,647E, 1K3R4E). MDA-MB-231 cells with a mutation at the p90RSK site (S703A-NHE1) changed from a wild-type mesenchymal morphology to a smaller epithelial-like phenotype with a loss of expression of mesenchymal marker vimentin. S703A cells also had reduced metastatic potential and markedly decreased rates of migration, invasion, spheroid growth, anchorage-dependent and soft agar colony formation. Similarly, BI-D1870, a specific inhibitor of p90RSK, significantly inhibited the metastatic potential of highly invasive MDA-MB-231 and moderately invasive MDA-MB-468 TNBC cells, but was minimally effective in non-invasive Hs578T TNBC cells. In contrast, invasion and spheroid growth were unaffected in cells containing NHE1 with mutations interfering with its activation by ERK1/2 (SSSA), though rates of migration and colony formation were reduced. Cells with a constitutive activation of NHE1 via the 1K3R4E mutation exhibited higher rates of migration, invasion, and spheroid growth. Taken together, our data demonstrate the critical role of NHE1 in metastasis, and suggest a novel link between NHE1 and the expression and cytosolic organization of vimentin, a key factor in epithelial-mesenchymal transition, that is dependent on p90RSK/14-3-3-mediated activation of the exchanger.
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Affiliation(s)
- Schammim Ray Amith
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | | | - Larry Fliegel
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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21
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Yeh ES, Williams CJ, Williams CB, Bonilla IV, Klauber-DeMore N, Phillips SL. Dysregulated connexin 43 in HER2-positive drug resistant breast cancer cells enhances proliferation and migration. Oncotarget 2017; 8:109358-109369. [PMID: 29312613 PMCID: PMC5752526 DOI: 10.18632/oncotarget.22678] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 11/01/2017] [Indexed: 12/16/2022] Open
Abstract
Connexin 43 (Cx43) is a gap junction protein whose function in the development of breast cancer and in breast cancer progression remains unclear. Evidence suggests that Cx43 (GJA1) mRNA and protein expression is altered in breast tumors. However, reports indicate both increased and decreased Cx43 levels in human breast cancer samples. Studies also suggest that loss of Cx43 regulated gap junction intercellular communication is a common feature of breast malignancies that potentially correlates with histological stage. Further evidence suggests that Cx43 (GJA1) mRNA expression is negatively correlated with HER2 positivity but a relationship between Cx43 and HER2 in breast cancer is not well defined. Therefore, in this study, we sought to evaluate the relationship between Cx43 activity, HER2, and drug resistance. Using HER2+ breast cancer cell lines that are sensitive or resistant to HER2 inhibitor, we evaluated Cx43 gap junction function. We found that Cx43 gap junction activity is completely lost in drug resistant HER2-positive (HER2+) breast cancer cells, whereas Cx43 gap junction activity can be restored by Cx43 overexpression in drug sensitive HER2+ cells. Moreover, the dysregulation of Cx43 resulted in increased tumorigenic and migratory capacity of the HER2+ drug resistant breast cancer cells.
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Affiliation(s)
- Elizabeth S Yeh
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Christina J Williams
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Carly Bess Williams
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Ingrid V Bonilla
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Nancy Klauber-DeMore
- Department of Surgery, Medical University of South Carolina, Charleston, SC, USA
| | - Stephanie L Phillips
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Medical University of South Carolina, Charleston, SC, USA
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22
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Antitumor activities of the synthetic retinoid ST1926 in two-dimensional and three-dimensional human breast cancer models. Anticancer Drugs 2017; 28:757-770. [DOI: 10.1097/cad.0000000000000511] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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23
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Leithe E, Mesnil M, Aasen T. The connexin 43 C-terminus: A tail of many tales. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:48-64. [PMID: 28526583 DOI: 10.1016/j.bbamem.2017.05.008] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/10/2017] [Accepted: 05/12/2017] [Indexed: 10/19/2022]
Abstract
Connexins are chordate gap junction channel proteins that, by enabling direct communication between the cytosols of adjacent cells, create a unique cell signalling network. Gap junctional intercellular communication (GJIC) has important roles in controlling cell growth and differentiation and in tissue development and homeostasis. Moreover, several non-canonical connexin functions unrelated to GJIC have been discovered. Of the 21 members of the human connexin family, connexin 43 (Cx43) is the most widely expressed and studied. The long cytosolic C-terminus (CT) of Cx43 is subject to extensive post-translational modifications that modulate its intracellular trafficking and gap junction channel gating. Moreover, the Cx43 CT contains multiple domains involved in protein interactions that permit crosstalk between Cx43 and cytoskeletal and regulatory proteins. These domains endow Cx43 with the capacity to affect cell growth and differentiation independently of GJIC. Here, we review the current understanding of the regulation and unique functions of the Cx43 CT, both as an essential component of full-length Cx43 and as an independent signalling hub. We highlight the complex regulatory and signalling networks controlled by the Cx43 CT, including the extensive protein interactome that underlies both gap junction channel-dependent and -independent functions. We discuss these data in relation to the recent discovery of the direct translation of specific truncated forms of Cx43. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Edward Leithe
- Department of Molecular Oncology, Institute for Cancer Research, University of Oslo, NO-0424 Oslo, Norway; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, NO-0424 Oslo, Norway
| | - Marc Mesnil
- STIM Laboratory ERL 7368 CNRS - Faculté des Sciences Fondamentales et Appliquées, Université de Poitiers, Poitiers 86073, France
| | - Trond Aasen
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, 08035 Barcelona, Spain.
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Localisation Microscopy of Breast Epithelial ErbB-2 Receptors and Gap Junctions: Trafficking after γ-Irradiation, Neuregulin-1β, and Trastuzumab Application. Int J Mol Sci 2017; 18:ijms18020362. [PMID: 28208769 PMCID: PMC5343897 DOI: 10.3390/ijms18020362] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/28/2017] [Accepted: 01/30/2017] [Indexed: 12/28/2022] Open
Abstract
In cancer, vulnerable breast epithelium malignance tendency correlates with number and activation of ErbB receptor tyrosine kinases. In the presented work, we observe ErbB receptors activated by irradiation-induced DNA injury or neuregulin-1β application, or alternatively, attenuated by a therapeutic antibody using high resolution fluorescence localization microscopy. The gap junction turnover coinciding with ErbB receptor activation and co-transport is simultaneously recorded. DNA injury caused by 4 Gray of 6 MeV photon γ-irradiation or alternatively neuregulin-1β application mobilized ErbB receptors in a nucleograde fashion—a process attenuated by trastuzumab antibody application. This was accompanied by increased receptor density, indicating packing into transport units. Factors mobilizing ErbB receptors also mobilized plasma membrane resident gap junction channels. The time course of ErbB receptor activation and gap junction mobilization recapitulates the time course of non-homologous end-joining DNA repair. We explain our findings under terms of DNA injury-induced membrane receptor tyrosine kinase activation and retrograde trafficking. In addition, we interpret the phenomenon of retrograde co-trafficking of gap junction connexons stimulated by ErbB receptor activation.
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25
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Recouvreux MS, Grasso EN, Echeverria PC, Rocha-Viegas L, Castilla LH, Schere-Levy C, Tocci JM, Kordon EC, Rubinstein N. RUNX1 and FOXP3 interplay regulates expression of breast cancer related genes. Oncotarget 2016; 7:6552-65. [PMID: 26735887 PMCID: PMC4872732 DOI: 10.18632/oncotarget.6771] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 11/28/2015] [Indexed: 12/21/2022] Open
Abstract
Runx1 participation in epithelial mammary cells is still under review. Emerging data indicates that Runx1 could be relevant for breast tumor promotion. However, to date no studies have specifically evaluated the functional contribution of Runx1 to control gene expression in mammary epithelial tumor cells. It has been described that Runx1 activity is defined by protein context interaction. Interestingly, Foxp3 is a breast tumor suppressor gene. Here we show that endogenous Runx1 and Foxp3 physically interact in normal mammary cells and this interaction blocks Runx1 transcriptional activity. Furthermore we demonstrate that Runx1 is able to bind to R-spondin 3 (RSPO3) and Gap Junction protein Alpha 1 (GJA1) promoters. This binding upregulates Rspo3 oncogene expression and downregulates GJA1 tumor suppressor gene expression in a Foxp3-dependent manner. Moreover, reduced Runx1 transcriptional activity decreases tumor cell migration properties. Collectively, these data provide evidence of a new mechanism for breast tumor gene expression regulation, in which Runx1 and Foxp3 physically interact to control mammary epithelial cell gene expression fate. Our work suggests for the first time that Runx1 could be involved in breast tumor progression depending on Foxp3 availability.
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Affiliation(s)
- María Sol Recouvreux
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina.,Present Address: Oncology Institute "Angel H Roffo", Buenos Aires, Argentina
| | - Esteban Nicolás Grasso
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina.,Present Address: Immunopharmacology Laboratory, IQUIBICEN-CONICET, FCEN-UBA, Buenos Aires, Argentina
| | | | - Luciana Rocha-Viegas
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina.,Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, UBA, Buenos Aires, Argentina
| | - Lucio Hernán Castilla
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Carolina Schere-Levy
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Johanna Melisa Tocci
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Edith Claudia Kordon
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina.,Departamento de Química Biológica, UBA, Buenos Aires, Argentina
| | - Natalia Rubinstein
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina.,Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, UBA, Buenos Aires, Argentina
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Connexin's Connection in Breast Cancer Growth and Progression. Int J Cell Biol 2016; 2016:9025905. [PMID: 27642298 PMCID: PMC5011527 DOI: 10.1155/2016/9025905] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 07/18/2016] [Indexed: 12/26/2022] Open
Abstract
Gap junctions are cell-to-cell junctions that are located in the basolateral surface of two adjoining cells. A gap junction channel is composed of a family of proteins called connexins. Gap junction channels maintain intercellular communication between two cells through the exchange of ions, small metabolites, and electrical signals. Gap junction channels or connexins are widespread in terms of their expression and function in maintaining the development, differentiation, and homeostasis of vertebrate tissues. Gap junction connexins play a major role in maintaining intercellular communication among different cell types of normal mammary gland for proper development and homeostasis. Connexins have also been implicated in the pathogenesis of breast cancer. Differential expression pattern of connexins and their gap junction dependent or independent functions provide pivotal cross talk of breast tumor cells with the surrounding stromal cell in the microenvironment. Substantial research from the last 20 years has accumulated ample evidences that allow us a better understanding of the roles that connexins play in the tumorigenesis of primary breast tumor and its metastatic progression. This review will summarize the knowledge about the connexins and gap junction activities in breast cancer highlighting the differential expression and functional dynamics of connexins in the pathogenesis of the disease.
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27
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Abstract
Communication among cells via direct cell-cell contact by connexin gap junctions, or between cell and extracellular environment via pannexin channels or connexin hemichannels, is a key factor in cell function and tissue homeostasis. Upon malignant transformation in different cancer types, the dysregulation of these connexin and pannexin channels and their effect in cellular communication, can either enhance or suppress tumorigenesis and metastasis. In this review, we will highlight the latest reports on the role of the well characterized connexin family and its ability to form gap junctions and hemichannels in cancer. We will also introduce the more recently discovered family of pannexin channels and our current knowledge about their involvement in cancer progression.
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Affiliation(s)
- Jean X Jiang
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, 78229, USA
| | - Silvia Penuela
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, N6A5C1, Canada.
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28
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Connexin 43, breast cancer tumor suppressor: Missed connections? Cancer Lett 2016; 374:117-126. [DOI: 10.1016/j.canlet.2016.02.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 01/28/2016] [Accepted: 02/03/2016] [Indexed: 12/21/2022]
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Dynamic changes in protein interaction between AKAP95 and Cx43 during cell cycle progression of A549 cells. Sci Rep 2016; 6:21224. [PMID: 26880274 PMCID: PMC4754773 DOI: 10.1038/srep21224] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 01/20/2016] [Indexed: 01/11/2023] Open
Abstract
Here we show that A-kinase anchoring protein 95 (AKAP95) and connexin 43 (Cx43) dynamically interact during cell cycle progression of lung cancer A549 cells. Interaction between AKAP95 and Cx43 at different cell cycle phases was examined by tandem mass spectrometry(MS/MS), confocal immunofluorescence microscopy, Western blot, and co-immunoprecipitation(Co-IP). Over the course of a complete cell cycle, interaction between AKAP95 and Cx43 occurred in two stages: binding stage from late G1 to metaphase, and separating stage from anaphase to late G1. The binding stage was further subdivided into complex binding to DNA in interphase and complex separating from DNA in metaphase. In late G1, Cx43 translocated to the nucleus via AKAP95; in anaphase, Cx43 separated from AKAP95 and aggregated between two daughter nuclei. In telophase, Cx43 aggregated at the membrane of the cleavage furrow. After mitosis, Cx43 was absent from the furrow membrane and was located in the cytoplasm. Binding between AKAP95 and Cx43 was reduced by N-(2-[P-Bromocinnamylamino]-ethyl)-5-isoquinolinesulfonmide (H89) treatment and enhanced by Forskolin. dynamic interaction between AKAP95 and Cx43 varies with cell cycle progression to regulate multiple biological processes.
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30
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Kong H, Liu X, Yang L, Qi K, Zhang H, Zhang J, Huang Z, Wang H. All-trans retinoic acid enhances bystander effect of suicide gene therapy in the treatment of breast cancer. Oncol Rep 2015; 35:1868-74. [PMID: 26717879 DOI: 10.3892/or.2015.4535] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Accepted: 11/24/2015] [Indexed: 11/05/2022] Open
Abstract
All-trans retinoic acid (ATRA) has been shown to enhance the expression of connexin 43 (Cx43) and the bystander effect (BSE) in suicide gene therapy. These in turn improve effects of suicide gene therapies for several tumor types. However, whether ATRA can improve BSE remains unclear in suicide gene therapy for breast cancer. In the present study, MCF-7, human breast cancer cells were treated with ATRA in combination with a VEGFP-TK/CD gene suicide system developed by our group. We found that this combination enhances the efficiency of cell killing and apoptosis of breast cancer by strengthening the BSE in vitro. ATRA also promotes gap junction intercellular communication (GJIC) in MCF-7 cells by upregulation of the connexin 43 mRNA and protein in MCF-7 cells. These results indicate that enhancement of GJIC by ATRA in suicide gene system might serve as an attractive and cost-effective strategy of therapy for breast cancer cells.
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Affiliation(s)
- Heng Kong
- Department of Thyroid and Breast Surgery, Shenzhen Key Laboratory for Endogenous Infection, Shenzhen Nanshan District People's Hospital (The Sixth People's Hospital of Shenzhen), Shenzhen, Guangdong 518052, P.R. China
| | - Xia Liu
- Department of Human Resource, Shenzhen Nanshan District People's Hospital, Shenzhen, Guangdong 518052, P.R. China
| | - Liucheng Yang
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Ke Qi
- Department of Thyroid and Breast Surgery, Shenzhen Key Laboratory for Endogenous Infection, Shenzhen Nanshan District People's Hospital (The Sixth People's Hospital of Shenzhen), Shenzhen, Guangdong 518052, P.R. China
| | - Haoyun Zhang
- Department of Thyroid and Breast Surgery, Shenzhen Key Laboratory for Endogenous Infection, Shenzhen Nanshan District People's Hospital (The Sixth People's Hospital of Shenzhen), Shenzhen, Guangdong 518052, P.R. China
| | - Jingwen Zhang
- Clinical Laboratory, Shenzhen Nanshan District People's Hospital, Shenzhen, Guangdong 518052, P.R. China
| | - Zonghai Huang
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Hongxian Wang
- Department of Thyroid and Breast Surgery, Shenzhen Key Laboratory for Endogenous Infection, Shenzhen Nanshan District People's Hospital (The Sixth People's Hospital of Shenzhen), Shenzhen, Guangdong 518052, P.R. China
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31
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Upregulation of connexin43 contributes to PX-12-induced oxidative cell death. Tumour Biol 2015; 37:7535-46. [PMID: 26684802 DOI: 10.1007/s13277-015-4620-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 12/10/2015] [Indexed: 01/24/2023] Open
Abstract
Thioredoxin (Trx) is a small redox protein that underlies aggressive tumor growth and resistance to chemotherapy. Inhibition of Trx with the chemical inhibitor PX-12 suppresses tumor growth and induces cell apoptosis. Currently, the mechanism underlying the therapeutic actions of PX-12 and the molecules influencing cell susceptibility to PX-12 are incompletely understood. Given that connexin43 (Cx43), a tumor suppressor, regulates tumor cell susceptibility to chemotherapy, we examined the possible involvement of Cx43 in PX-12-induced cell death. Exposure of cells to PX-12 led to a loss of cell viability, which was associated with the activation of oxidative sensitive c-Jun N-terminal kinase (JNK). Inhibition of JNK or supplement of cells with anti-oxidants prevented the cell-killing action of PX-12. The forced expression of Cx43 in normal and tumor cells increased cell sensitivity to PX-12-induced JNK activation and cell death. In contrast, the downregulation of Cx43 with siRNA or the suppression of gap junctions with chemical inhibitors attenuated JNK activation and enhanced cell resistance to PX-12. Further analysis revealed that PX-12 at low concentrations induced a JNK-dependent elevation in the Cx43 protein, which was also preventable by supplementing the cells with anti-oxidants. Our results thus indicate that Cx43 is a determinant in the regulation of cell susceptibility to PX-12 and that the upregulation of Cx43 may be an additional mechanism by which PX-12 exerts its anti-tumor actions.
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Qiu X, Cheng JC, Zhao J, Chang HM, Leung PCK. Transforming growth factor-β stimulates human ovarian cancer cell migration by up-regulating connexin43 expression via Smad2/3 signaling. Cell Signal 2015; 27:1956-62. [PMID: 26186970 DOI: 10.1016/j.cellsig.2015.07.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 07/13/2015] [Indexed: 11/24/2022]
Abstract
Reduced connexin43 (Cx43) expression is frequently detected in different types of human cancer. Cx43 has been shown to regulate cancer cell migration in a cell-type dependent manner. In both primary and recurrent human ovarian cancer, overexpression of TGF-β ligand and its receptors have been detected. TGF-β can regulate Cx43 expression in other cell types and stimulate human ovarian cancer cell migration. However, whether Cx43 can be regulated by TGF-β and is involved in TGF-β-stimulated cell migration in human ovarian cancer cells remain unknown. In this study, we demonstrate that TGF-β up-regulates Cx43 in two human ovarian cancer cell lines, SKOV3 and OVCAR4. The stimulatory effect of TGF-β on Cx43 expression is blocked by inhibition of TGF-β receptor. Treatment with TGF-β activates Smad2 and Smad3 signaling pathways in both ovarian cancer cell lines. In addition, siRNA-mediated knockdown of Smad2 or Smd3 abolishes TGF-β-induced up-regulation of Cx43 expression. Moreover, knockdown of Cx43 attenuates TGF-β-stimulated cell migration. This study demonstrates an important role for Cx43 in mediating the effects of TGF-β on human ovarian cancer cell migration.
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Affiliation(s)
- Xin Qiu
- Department of Obstetrics and Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Jung-Chien Cheng
- Department of Obstetrics and Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Jianfang Zhao
- Department of Obstetrics and Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Hsun-Ming Chang
- Department of Obstetrics and Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Peter C K Leung
- Department of Obstetrics and Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada.
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Dolcino M, Ottria A, Barbieri A, Patuzzo G, Tinazzi E, Argentino G, Beri R, Lunardi C, Puccetti A. Gene Expression Profiling in Peripheral Blood Cells and Synovial Membranes of Patients with Psoriatic Arthritis. PLoS One 2015; 10:e0128262. [PMID: 26086874 PMCID: PMC4473102 DOI: 10.1371/journal.pone.0128262] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 04/24/2015] [Indexed: 12/22/2022] Open
Abstract
Background Psoriatic arthritis (PsA) is an inflammatory arthritis whose pathogenesis is poorly understood; it is characterized by bone erosions and new bone formation. The diagnosis of PsA is mainly clinical and diagnostic biomarkers are not yet available. The aim of this work was to clarify some aspects of the disease pathogenesis and to identify specific gene signatures in paired peripheral blood cells (PBC) and synovial biopsies of patients with PsA. Moreover, we tried to identify biomarkers that can be used in clinical practice. Methods PBC and synovial biopsies of 10 patients with PsA were used to study gene expression using Affymetrix arrays. The expression values were validated by Q-PCR, FACS analysis and by the detection of soluble mediators. Results Synovial biopsies of patients showed a modulation of approximately 200 genes when compared to the biopsies of healthy donors. Among the differentially expressed genes we observed the upregulation of Th17 related genes and of type I interferon (IFN) inducible genes. FACS analysis confirmed the Th17 polarization. Moreover, the synovial trascriptome shows gene clusters (bone remodeling, angiogenesis and inflammation) involved in the pathogenesis of PsA. Interestingly 90 genes are modulated in both compartments (PBC and synovium) suggesting that signature pathways in PBC mirror those of the inflamed synovium. Finally the osteoactivin gene was upregulared in both PBC and synovial biopsies and this finding was confirmed by the detection of high levels of osteoactivin in PsA sera but not in other inflammatory arthritides. Conclusions We describe the first analysis of the trancriptome in paired synovial tissue and PBC of patients with PsA. This study strengthens the hypothesis that PsA is of autoimmune origin since the coactivity of IFN and Th17 pathways is typical of autoimmunity. Finally these findings have allowed the identification of a possible disease biomarker, osteoactivin, easily detectable in PsA serum.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Antonio Puccetti
- Institute G. Gaslini, Genova, Italy
- University of Genova, Genova, Italy
- * E-mail:
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Anti-Inflammatory and Cytostatic Activities of a Parthenolide-Like Sesquiterpene Lactone from Cota palaestina subsp. syriaca. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:474597. [PMID: 26089941 PMCID: PMC4452324 DOI: 10.1155/2015/474597] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 04/14/2015] [Indexed: 11/17/2022]
Abstract
A sesquiterpene lactone 1-β,10-Epoxy-6-hydroxy-1,10H-inunolide (K100) was isolated through "bioassay-guided fractionation" from Cota palaestina subsp. syriaca, an Eastern Mediterranean endemic plant. K100 inhibited endotoxin- (ET-) induced proinflammatory markers: IL-6, MMP-9, and NO in normal mouse mammary SCp2 Cells. Molecular docking in silico suggested that K100, having highly analogous structure as parthenolide (PTL), an anticancer compound, could bind PTL target proteins at similar positions and with comparable binding affinities. Both compounds, K100 and PTL, inhibited the proliferation and prolonged the S-phase of the cell cycle of breast adenocarcinoma MDA-MB-231 cells grown in 2D cultures. Noncytotoxic concentrations of K100 and PTL decreased the proliferation rate of MDA-MB-231 and shifted their morphology from stellate to spherical colonies in 3D cultures. This was accompanied with a significant increase in the amount of small colonies and a decrease in the amount of large colonies. Moreover, K100 and PTL decreased cellular motility and invasiveness of MDA-MB-231 cells. In summary, these results suggest that K100 exhibits PTL-analogous anti-inflammatory, cytostatic, and antimetastatic effects.
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Grek CL, Rhett JM, Bruce JS, Abt MA, Ghatnekar GS, Yeh ES. Targeting connexin 43 with α-connexin carboxyl-terminal (ACT1) peptide enhances the activity of the targeted inhibitors, tamoxifen and lapatinib, in breast cancer: clinical implication for ACT1. BMC Cancer 2015; 15:296. [PMID: 25881004 PMCID: PMC4407347 DOI: 10.1186/s12885-015-1229-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 03/19/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Treatment failure is a critical issue in breast cancer and identifying useful interventions that optimize current cancer therapies remains a critical unmet need. Expression and functional studies have identified connexins (Cxs), a family of gap junction proteins, as potential tumor suppressors. Studies suggest that Cx43 has a role in breast cancer cell proliferation, differentiation, and migration. Although pan-gap junction drugs are available, the lack of specificity of these agents increases the opportunity for off target effects. Consequently, a therapeutic agent that specifically modulates Cx43 would be beneficial and has not been tested in breast cancer. In this study, we now test an agent that specifically targets Cx43, called ACT1, in breast cancer. METHODS We evaluated whether direct modulation of Cx43 using a Cx43-directed therapeutic peptide, called ACT1, enhances Cx43 gap junctional activity in breast cancer cells, impairs breast cancer cell proliferation or survival, and enhances the activity of the targeted inhibitors tamoxifen and lapatinib. RESULTS Our results show that therapeutic modulation of Cx43 by ACT1 maintains Cx43 at gap junction sites between cell-cell membrane borders of breast cancer cells and augments gap junction activity in functional assays. The increase in Cx43 gap junctional activity achieved by ACT1 treatment impairs proliferation or survival of breast cancer cells but ACT1 has no effect on non-transformed MCF10A cells. Furthermore, treating ER+ breast cancer cells with a combination of ACT1 and tamoxifen or HER2+ breast cancer cells with ACT1 and lapatinib augments the activity of these targeted inhibitors. CONCLUSIONS Based on our findings, we conclude that modulation of Cx43 activity in breast cancer can be effectively achieved with the agent ACT1 to sustain Cx43-mediated gap junctional activity resulting in impaired malignant progression and enhanced activity of lapatinib and tamoxifen, implicating ACT1 as part of a combination regimen in breast cancer.
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Affiliation(s)
- Christina L Grek
- FirstString Research, Inc., 300 W. Coleman Blvd., Suite 203, Mount Pleasant, SC, USA.
| | - Joshua Matthew Rhett
- Department of Surgery, Division of General Surgery, Medical University of South Carolina, Charleston, SC, USA.
| | - Jaclynn S Bruce
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Ave, BSB358, MSC509, Charleston, SC, 29425, USA.
| | - Melissa A Abt
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Ave, BSB358, MSC509, Charleston, SC, 29425, USA.
| | - Gautam S Ghatnekar
- FirstString Research, Inc., 300 W. Coleman Blvd., Suite 203, Mount Pleasant, SC, USA.
| | - Elizabeth S Yeh
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Ave, BSB358, MSC509, Charleston, SC, 29425, USA.
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Aasen T. Connexins: junctional and non-junctional modulators of proliferation. Cell Tissue Res 2014; 360:685-99. [PMID: 25547217 DOI: 10.1007/s00441-014-2078-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 11/14/2014] [Indexed: 12/11/2022]
Abstract
Mounting evidence indicates that dysregulation of gap junctions and their structural subunits-connexins-often occurs in, and sometimes causes, a variety of proliferative disorders, including cancer. Connexin-mediated regulation of cell proliferation is complex and may involve modulation of gap junction intercellular communication (GJIC), hemichannel signalling, or gap junction-independent paths. However, the exact mechanisms linking connexins to proliferation remain poorly defined and a number of contradictory studies report both pro- and anti-proliferative effects, effects that often depend on the cell or tissue type or the microenvironment. The present review covers junctional and non-junctional regulation of proliferation by connexins, with a particular emphasis on their association with cancer.
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Affiliation(s)
- Trond Aasen
- Molecular Pathology Group, Vall d'Hebron Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Passeig Vall d'Hebron 119-129, Barcelona, 08035, Spain,
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Grek CL, Rhett JM, Ghatnekar GS. Cardiac to cancer: connecting connexins to clinical opportunity. FEBS Lett 2014; 588:1349-64. [PMID: 24607540 DOI: 10.1016/j.febslet.2014.02.047] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 02/25/2014] [Accepted: 02/26/2014] [Indexed: 12/26/2022]
Abstract
Gap junctions and their connexin components are indispensable in mediating the cellular coordination required for tissue and organ homeostasis. The critical nature of their existence mandates a connection to disease while at the same time offering therapeutic potential. Therapeutic intervention may be offered through the pharmacological and molecular disruption of the pathways involved in connexin biosynthesis, gap junction assembly, stabilization, or degradation. Chemical inhibitors aimed at closing connexin channels, peptide mimetics corresponding to short connexin sequences, and gene therapy approaches have been incredibly useful molecular tools in deciphering the complexities associated with connexin biology. Recently, therapeutic potential in targeting connexins has evolved from basic research in cell-based models to clinical opportunity in the form of human trials. Clinical promise is particularly evident with regards to targeting connexin43 in the context of wound healing. The following review is aimed at highlighting novel advances where the pharmacological manipulation of connexin biology has proven beneficial in animals or humans.
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Affiliation(s)
- Christina L Grek
- FirstString Research, Inc., 300 W. Coleman Blvd., Suite 203, Mount Pleasant, SC, United States
| | - J Matthew Rhett
- Department of Surgery, Division of General Surgery, Medical University of South Carolina, Charleston, SC, United States
| | - Gautam S Ghatnekar
- FirstString Research, Inc., 300 W. Coleman Blvd., Suite 203, Mount Pleasant, SC, United States.
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