1
|
Feng Y, Hu X, Zhang Y, Wang Y. The Role of Microglia in Brain Metastases: Mechanisms and Strategies. Aging Dis 2024; 15:169-185. [PMID: 37307835 PMCID: PMC10796095 DOI: 10.14336/ad.2023.0514] [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: 12/29/2022] [Accepted: 05/14/2023] [Indexed: 06/14/2023] Open
Abstract
Brain metastases and related complications are one of the major fatal factors in cancer. Patients with breast cancer, lung cancer, and melanoma are at a high risk of developing brain metastases. However, the mechanisms underlying the brain metastatic cascade remain poorly understood. Microglia, one of the major resident macrophages in the brain parenchyma, are involved in multiple processes associated with brain metastasis, including inflammation, angiogenesis, and immune modulation. They also closely interact with metastatic cancer cells, astrocytes, and other immune cells. Current therapeutic approaches against metastatic brain cancers, including small-molecule drugs, antibody-coupled drugs (ADCs), and immune-checkpoint inhibitors (ICIs), have compromised efficacy owing to the impermeability of the blood-brain barrier (BBB) and complex brain microenvironment. Targeting microglia is one of the strategies for treating metastatic brain cancer. In this review, we summarize the multifaceted roles of microglia in brain metastases and highlight them as potential targets for future therapeutic interventions.
Collapse
Affiliation(s)
- Ying Feng
- Department of Medical Oncology, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Xueqing Hu
- Department of Medical Oncology, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Yingru Zhang
- Department of Medical Oncology, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Yan Wang
- Department of Medical Oncology, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| |
Collapse
|
2
|
Lai Y, Wu W, Liang X, Zhong F, An L, Chang Z, Cai C, He Z, Wu W. Connexin43 is associated with the progression of clear cell renal carcinoma and is regulated by tangeretin to sygergize with tyrosine kinase inhibitors. Transl Oncol 2023; 35:101712. [PMID: 37354638 DOI: 10.1016/j.tranon.2023.101712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 05/31/2023] [Accepted: 06/07/2023] [Indexed: 06/26/2023] Open
Abstract
BACKGROUND The roles of Connexin43 (Cx43) in clear cell renal cell carcinoma (ccRCC) microenviroment remains to be poorly defined. METHODS The expression profile, prognosis and immune analysis of Cx43 in various cancers, particularly in ccRCC were performed using TCGA database, and various biological function assays were applied to explore the physiological role of Cx43 and tangeretin in ccRCC. Western blot were applied to examine the protein expression and Kunming mice were used to evaluate preliminary safety or anti-tumor activity of tangeretin and sunitinib. RESULTS Compared with the normal group, higher expression levels of Cx43 in ccRCC, and distinct associations between Cx43 expression and ccRCC prognosis or immune infiltration, were found. Notably, the expression of Cx43 was found to be highly correlated with that of receptor tyrosine kinases (RTKs), particularly with VEGFR1, VEGFR2 and VEGFR3. The expression of Cx43 and EGFR was also found to be higher in ccRCC than that in the para-cancerous specimens. Knocking down Cx43 expression decreased RCC cell viability, cell migration, p-EGFR, MMP-9 and survivin expression. Using 14 Chinese medicine monomers, tangeretin was screened and found to inhibit tumor cell viability and Cx43 expression. Tangeretin also enhanced the sensitivity of RCC cells to tyrosine kinase inhibitors (TKIs) sunitinib and sorafenib. However, the same concentration of tangeretin exerted a less prominent effect on normal renal cell viability. CONCLUSIONS Cx43 is strongly associated with RTK expression and ccRCC progression, while tangeretin can inhibit RCC cell malignancy by inhibiting Cx43 expression and enhance the sensitivity of RCC cells to TKIs.
Collapse
Affiliation(s)
- Yongchang Lai
- Department of Urology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong 518033, P.R. China; Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Weizhou Wu
- Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Xiongfa Liang
- Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Fangling Zhong
- Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Lingyue An
- Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Zhenglin Chang
- Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Chao Cai
- Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China
| | - Zhaohui He
- Department of Urology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong 518033, P.R. China.
| | - Wenqi Wu
- Department of Urology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510260, P.R. China; Department of Urology, Guangdong Key Laboratory of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Urology Research Institute, P.R. China.
| |
Collapse
|
3
|
Orellana VP, Tittarelli A, Retamal MA. Connexins in melanoma: Potential role of Cx46 in its aggressiveness. Pigment Cell Melanoma Res 2021; 34:853-868. [PMID: 33140904 DOI: 10.1111/pcmr.12945] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/20/2020] [Accepted: 10/27/2020] [Indexed: 12/19/2022]
Abstract
Melanoma is the most aggressive skin cancer, and in metastatic advanced states, it is completely refractory to chemotherapy. Therefore, it is relevant to understand the molecular bases that rule their aggressiveness. Connexins (Cxs) are proteins that under normal physiological conditions participate in intercellular communication, via the exchange of signaling molecules between the cytoplasm and extracellular milieu and the exchange of ions/second messengers between the cytoplasm of contacting cells. These proteins have shown important roles in cancer progression, chemo- and radiotherapy resistance, and metastasis. Accordingly, Cx26 and Cx43 seem to play important roles in melanoma progression and metastasis. On the other hand, Cx46 is typically expressed in the eye lens, where it seems to be associated with oxidative stress protection in fiber lens cells. However, in the last decade, Cx46 expression has been associated with breast and brain cancers, due to its role in potentiation of both extracellular vesicle release and cancer stem cell-like properties. In this review, we analyzed a potential role of Cx46 as a new biomarker and therapeutic target in melanoma.
Collapse
Affiliation(s)
- Viviana P Orellana
- Universidad del Desarrollo. Centro de Fisiología Celular e Integrativa, Clinica Alemana Facultad de Medicina, Santiago, Chile
- Universidad del Desarrollo. Programa de Comunicación Celular en Cáncer, Clínica Alemana Facultad de Medicina, Santiago, Chile
| | - Andrés Tittarelli
- Programa Institucional de Fomento a la Investigación, Desarrollo e Innovación (PIDi), Universidad Tecnológica Metropolitana (UTEM), Santiago, Chile
| | - Mauricio A Retamal
- Universidad del Desarrollo. Centro de Fisiología Celular e Integrativa, Clinica Alemana Facultad de Medicina, Santiago, Chile
- Universidad del Desarrollo. Programa de Comunicación Celular en Cáncer, Clínica Alemana Facultad de Medicina, Santiago, Chile
| |
Collapse
|
4
|
Sato H, Shimizu A, Okawa T, Uzu M, Goto M, Hisaka A. Metabolome Shift in Both Metastatic Breast Cancer Cells and Astrocytes Which May Contribute to the Tumor Microenvironment. Int J Mol Sci 2021; 22:ijms22147430. [PMID: 34299050 PMCID: PMC8308096 DOI: 10.3390/ijms22147430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 06/26/2021] [Accepted: 07/09/2021] [Indexed: 12/17/2022] Open
Abstract
The role of astrocytes in the periphery of metastatic brain tumors is unclear. Since astrocytes regulate central nervous metabolism, we hypothesized that changes in astrocytes induced by contact with cancer cells would appear in the metabolome of both cells and contribute to malignant transformation. Coculture of astrocytes with breast cancer cell supernatants altered glutamate (Glu)-centered arginine–proline metabolism. Similarly, the metabolome of cancer cells was also altered by astrocyte culture supernatants, and the changes were further amplified in astrocytes exposed to Glu. Inhibition of Glu uptake in astrocytes reduces the variability in cancer cells. Principal component analysis of the cancer cells revealed that all these changes were in the first principal component (PC1) axis, where the responsible metabolites were involved in the metabolism of the arginine–proline, pyrimidine, and pentose phosphate pathways. The contribution of these changes to the tumor microenvironment needs to be further pursued.
Collapse
Affiliation(s)
- Hiromi Sato
- Laboratory of Clinical Pharmacology and Pharmacometrics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan; (A.S.); (T.O.); (M.U.); (M.G.); (A.H.)
- Correspondence:
| | - Ayaka Shimizu
- Laboratory of Clinical Pharmacology and Pharmacometrics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan; (A.S.); (T.O.); (M.U.); (M.G.); (A.H.)
| | - Toya Okawa
- Laboratory of Clinical Pharmacology and Pharmacometrics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan; (A.S.); (T.O.); (M.U.); (M.G.); (A.H.)
| | - Miaki Uzu
- Laboratory of Clinical Pharmacology and Pharmacometrics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan; (A.S.); (T.O.); (M.U.); (M.G.); (A.H.)
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Momoko Goto
- Laboratory of Clinical Pharmacology and Pharmacometrics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan; (A.S.); (T.O.); (M.U.); (M.G.); (A.H.)
| | - Akihiro Hisaka
- Laboratory of Clinical Pharmacology and Pharmacometrics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8675, Japan; (A.S.); (T.O.); (M.U.); (M.G.); (A.H.)
| |
Collapse
|
5
|
Mulkearns-Hubert EE, Reizes O, Lathia JD. Connexins in Cancer: Jekyll or Hyde? Biomolecules 2020; 10:E1654. [PMID: 33321749 PMCID: PMC7764653 DOI: 10.3390/biom10121654] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/07/2020] [Accepted: 12/08/2020] [Indexed: 12/16/2022] Open
Abstract
The expression, localization, and function of connexins, the protein subunits that comprise gap junctions, are often altered in cancer. In addition to cell-cell coupling through gap junction channels, connexins also form hemichannels that allow communication between the cell and the extracellular space and perform non-junctional intracellular activities. Historically, connexins have been considered tumor suppressors; however, they can also serve tumor-promoting functions in some contexts. Here, we review the literature surrounding connexins in cancer cells in terms of specific connexin functions and propose that connexins function upstream of most, if not all, of the hallmarks of cancer. The development of advanced connexin targeting approaches remains an opportunity for the field to further interrogate the role of connexins in cancer phenotypes, particularly through the use of in vivo models. More specific modulators of connexin function will both help elucidate the functions of connexins in cancer and advance connexin-specific therapies in the clinic.
Collapse
Affiliation(s)
- Erin E. Mulkearns-Hubert
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA; (O.R.); (J.D.L.)
| | - Ofer Reizes
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA; (O.R.); (J.D.L.)
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College, Medicine of Case Western Reserve University, Cleveland, OH 44195, USA
| | - Justin D. Lathia
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA; (O.R.); (J.D.L.)
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College, Medicine of Case Western Reserve University, Cleveland, OH 44195, USA
- Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, OH, 44195, USA
| |
Collapse
|
6
|
Chu H, Gao Z, Huang C, Dong J, Tang Y, Dong Q. Relationship Between Hematoma Expansion Induced by Hypertension and Hyperglycemia and Blood-brain Barrier Disruption in Mice and Its Possible Mechanism: Role of Aquaporin-4 and Connexin43. Neurosci Bull 2020; 36:1369-1380. [PMID: 32623691 PMCID: PMC7674541 DOI: 10.1007/s12264-020-00540-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 03/24/2020] [Indexed: 12/24/2022] Open
Abstract
We aimed to select an optimized hematoma expansion (HE) model and investigate the possible mechanism of blood-brain barrier (BBB) damage in mice. The results showed that HE occurred in the group with hypertension combined with hyperglycemia (HH-HE) from 3 to 72 h after intracerebral hemorrhage; this was accompanied by neurological deficits and hardly influenced the survival rate. The receiver operating characteristic curve suggested the criterion for this model was hematoma volume expansion ≥ 45.0%. Meanwhile, HH-HE aggravated BBB disruption. A protector of the BBB reduced HH-HE, while a BBB disruptor induced a further HH-HE. Aquaporin-4 (AQP4) knock-out led to larger hematoma volume and more severe BBB disruption. Furthermore, hematoma volume and BBB disruption were reduced by multiple connexin43 (Cx43) inhibitors in the wild-type group but not in the AQP4 knock-out group. In conclusion, the optimized HE model is induced by hypertension and hyperglycemia with the criterion of hematoma volume expanding ≥ 45.0%. HH-HE leads to BBB disruption, which is dependent on AQP4 and Cx43.
Collapse
Affiliation(s)
- Heling Chu
- Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200040, China
- Department of Neurology, North Huashan Hospital, Fudan University, Shanghai, 201907, China
| | - Zidan Gao
- Department of Neurology, Affiliated Hospital of Guizhou Medical University, Guiyang, 550004, China
| | - Chuyi Huang
- Department of Neurology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Jing Dong
- Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200040, China
| | - Yuping Tang
- Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200040, China.
| | - Qiang Dong
- Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200040, China.
| |
Collapse
|
7
|
Fumagalli A, Heuninck J, Pizzoccaro A, Moutin E, Koenen J, Séveno M, Durroux T, Junier MP, Schlecht-Louf G, Bachelerie F, Schütz D, Stumm R, Smit MJ, Guérineau NC, Chaumont-Dubel S, Marin P. The atypical chemokine receptor 3 interacts with Connexin 43 inhibiting astrocytic gap junctional intercellular communication. Nat Commun 2020; 11:4855. [PMID: 32978390 PMCID: PMC7519114 DOI: 10.1038/s41467-020-18634-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/02/2020] [Indexed: 12/12/2022] Open
Abstract
The atypical chemokine receptor 3 (ACKR3) plays a pivotal role in directing the migration of various cellular populations and its over-expression in tumors promotes cell proliferation and invasiveness. The intracellular signaling pathways transducing ACKR3-dependent effects remain poorly characterized, an issue we addressed by identifying the interactome of ACKR3. Here, we report that recombinant ACKR3 expressed in HEK293T cells recruits the gap junction protein Connexin 43 (Cx43). Cx43 and ACKR3 are co-expressed in mouse brain astrocytes and human glioblastoma cells and form a complex in embryonic mouse brain. Functional in vitro studies show enhanced ACKR3 interaction with Cx43 upon ACKR3 agonist stimulation. Furthermore, ACKR3 activation promotes β-arrestin2- and dynamin-dependent Cx43 internalization to inhibit gap junctional intercellular communication in primary astrocytes. These results demonstrate a functional link between ACKR3 and gap junctions that might be of pathophysiological relevance. The atypical chemokine receptor 3 (ACKR3) is known to regulate cell migration, but the underlying mechanisms are unclear. Here, the authors show, from an interactome analysis, ACKR3 association with the gap junction protein Connexin 43 in vivo and ACKR3-mediated inhibition of astrocyte gap junctional communication.
Collapse
Affiliation(s)
- Amos Fumagalli
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Joyce Heuninck
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Anne Pizzoccaro
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Enora Moutin
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Joyce Koenen
- Université Paris-Saclay, Inserm, Inflammation, Microbiome and Immunosurveillance, 92140, Clamart, France.,Amsterdam Institute for Molecules Medicines and Systems, Division of Medicinal Chemistry, Faculty of Sciences, VU University Amsterdam, 1081, HV, Amsterdam, The Netherlands
| | - Martial Séveno
- Biocampus Montpellier, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Thierry Durroux
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Marie-Pierre Junier
- CNRS UMR8246, Inserm U1130, Neuroscience Paris Seine-IBPS, Sorbonne Universités, Paris, France
| | - Géraldine Schlecht-Louf
- Université Paris-Saclay, Inserm, Inflammation, Microbiome and Immunosurveillance, 92140, Clamart, France
| | - Francoise Bachelerie
- Université Paris-Saclay, Inserm, Inflammation, Microbiome and Immunosurveillance, 92140, Clamart, France
| | - Dagmar Schütz
- Institute of Pharmacology and Toxicology, Jena University Hospital, 07747, Jena, Germany
| | - Ralf Stumm
- Institute of Pharmacology and Toxicology, Jena University Hospital, 07747, Jena, Germany
| | - Martine J Smit
- Amsterdam Institute for Molecules Medicines and Systems, Division of Medicinal Chemistry, Faculty of Sciences, VU University Amsterdam, 1081, HV, Amsterdam, The Netherlands
| | - Nathalie C Guérineau
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Séverine Chaumont-Dubel
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Philippe Marin
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.
| |
Collapse
|
8
|
Khosla K, Naus CC, Sin WC. Cx43 in Neural Progenitors Promotes Glioma Invasion in a 3D Culture System. Int J Mol Sci 2020; 21:ijms21155216. [PMID: 32717889 PMCID: PMC7432065 DOI: 10.3390/ijms21155216] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/12/2020] [Accepted: 07/20/2020] [Indexed: 12/21/2022] Open
Abstract
The environment that envelops the cancer cells intimately affects the malignancy of human cancers. In the case of glioma, an aggressive adult brain cancer, its high rate of recurrence after total resection is responsible for a poor prognosis. Connexin43 (Cx43) is a gap junction protein with a prominent presence in glioma-associated normal brain cells, specifically in the reactive astrocytes. We previously demonstrated that elimination of Cx43 in these astrocytes reduces glioma invasion in a syngeneic mouse model. To further our investigation in human glioma cells, we developed a scaffold-free 3D platform that takes into account both the tumor and its interaction with the surrounding tissue. Using cell-tracking dyes and 3D laser scanning confocal microscopy, we now report that the elimination of Cx43 protein in neural progenitor spheroids reduced the invasiveness of human brain tumor-initiating cells, confirming our earlier observation in an intact mouse brain. By investigating the glioma invasion in a defined multicellular system with a tumor boundary that mimics the intact brain environment, our findings strengthen Cx43 as a candidate target for glioma control.
Collapse
|
9
|
Picoli C, Soleilhac E, Journet A, Barette C, Comte M, Giaume C, Mouthon F, Fauvarque MO, Charvériat M. High-Content Screening Identifies New Inhibitors of Connexin 43 Gap Junctions. Assay Drug Dev Technol 2020; 17:240-248. [PMID: 31314551 DOI: 10.1089/adt.2019.927] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Gap junctions (GJs) are dynamic structures composed of hexamers of connexins (Cxs), a class of transmembrane proteins enabling channel-mediated direct intercellular communication through cell-cell diffusion of ions and small metabolites. In defined conditions, Cxs also work as hemichannels allowing exchanges between the cytoplasm and the extracellular medium. The most common GJ channel is formed by connexin 43 (Cx43) and plays an important role in physiological and pathological processes in excitable tissues, such as heart and brain. Hence, Cx43 has been largely envisioned as a new therapeutic target in cancer, neurological and psychiatric indications, or cardiovascular diseases. Identifying new pharmacological inhibitors of Cx43 GJs with different mechanisms of action and from diverse chemical classes is thus highly challenging. We present here a high-content screening method, based on the evaluation of fluorescent dye transfer rates between adjacent cells to monitor the function of GJs in U251 glioblastoma cells expressing high levels of Cx43. This assay was validated using well-described pharmacological GJ inhibitors such as mefloquine. The method was adapted to screen a library of 1,280 Food and Drug Administration- and European Medicines Agency-approved drugs that led to the selection of both known and new inhibitors of GJ channel function. We further focused on a specific class of microtubule-targeting agents, confirming that a proper tubulin network is required for functional Cx43 GJ channels.
Collapse
Affiliation(s)
| | - Emmanuelle Soleilhac
- 2Univ. Grenoble Alpes, CEA, Inserm, IRIG BGE-Genetics and Chemogenomics, Grenoble, France
| | - Agnès Journet
- 2Univ. Grenoble Alpes, CEA, Inserm, IRIG BGE-Genetics and Chemogenomics, Grenoble, France
| | - Caroline Barette
- 2Univ. Grenoble Alpes, CEA, Inserm, IRIG BGE-Genetics and Chemogenomics, Grenoble, France
| | - Marjorie Comte
- 2Univ. Grenoble Alpes, CEA, Inserm, IRIG BGE-Genetics and Chemogenomics, Grenoble, France
| | | | | | - Marie-Odile Fauvarque
- 2Univ. Grenoble Alpes, CEA, Inserm, IRIG BGE-Genetics and Chemogenomics, Grenoble, France
| | | |
Collapse
|
10
|
Megalencephalic Leukoencephalopathy with Subcortical Cysts Disease-Linked MLC1 Protein Favors Gap-Junction Intercellular Communication by Regulating Connexin 43 Trafficking in Astrocytes. Cells 2020; 9:cells9061425. [PMID: 32521795 PMCID: PMC7348769 DOI: 10.3390/cells9061425] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 01/06/2023] Open
Abstract
Astrocytes, the most numerous cells of the central nervous system, exert critical functions for brain homeostasis. To this purpose, astrocytes generate a highly interconnected intercellular network allowing rapid exchange of ions and metabolites through gap junctions, adjoined channels composed of hexamers of connexin (Cx) proteins, mainly Cx43. Functional alterations of Cxs and gap junctions have been observed in several neuroinflammatory/neurodegenerative diseases. In the rare leukodystrophy megalencephalic leukoencephalopathy with subcortical cysts (MLC), astrocytes show defective control of ion/fluid exchanges causing brain edema, fluid cysts, and astrocyte/myelin vacuolation. MLC is caused by mutations in MLC1, an astrocyte-specific protein of elusive function, and in GlialCAM, a MLC1 chaperon. Both proteins are highly expressed at perivascular astrocyte end-feet and astrocyte-astrocyte contacts where they interact with zonula occludens-1 (ZO-1) and Cx43 junctional proteins. To investigate the possible role of Cx43 in MLC pathogenesis, we studied Cx43 properties in astrocytoma cells overexpressing wild type (WT) MLC1 or MLC1 carrying pathological mutations. Using biochemical and electrophysiological techniques, we found that WT, but not mutated, MLC1 expression favors intercellular communication by inhibiting extracellular-signal-regulated kinase 1/2 (ERK1/2)-mediated Cx43 phosphorylation and increasing Cx43 gap-junction stability. These data indicate MLC1 regulation of Cx43 in astrocytes and Cx43 involvement in MLC pathogenesis, suggesting potential target pathways for therapeutic interventions.
Collapse
|
11
|
Buruiană A, Florian ȘI, Florian AI, Timiș TL, Mihu CM, Miclăuș M, Oșan S, Hrapșa I, Cataniciu RC, Farcaș M, Șușman S. The Roles of miRNA in Glioblastoma Tumor Cell Communication: Diplomatic and Aggressive Negotiations. Int J Mol Sci 2020; 21:ijms21061950. [PMID: 32178454 PMCID: PMC7139390 DOI: 10.3390/ijms21061950] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 02/07/2023] Open
Abstract
Glioblastoma (GBM) consists of a heterogeneous collection of competing cellular clones which communicate with each other and with the tumor microenvironment (TME). MicroRNAs (miRNAs) present various exchange mechanisms: free miRNA, extracellular vesicles (EVs), or gap junctions (GJs). GBM cells transfer miR-4519 and miR-5096 to astrocytes through GJs. Oligodendrocytes located in the invasion front present high levels of miR-219-5p, miR-219-2-3p, and miR-338-3p, all related to their differentiation. There is a reciprocal exchange between GBM cells and endothelial cells (ECs) as miR-5096 promotes angiogenesis after being transferred into ECs, whereas miR-145-5p acts as a tumor suppressor. In glioma stem cells (GSCs), miR-1587 and miR-3620-5p increase the proliferation and miR-1587 inhibits the hormone receptor co-repressor-1 (NCOR1) after EVs transfers. GBM-derived EVs carry miR-21 and miR-451 that are up-taken by microglia and monocytes/macrophages, promoting their proliferation. Macrophages release EVs enriched in miR-21 that are transferred to glioma cells. This bidirectional miR-21 exchange increases STAT3 activity in GBM cells and macrophages, promoting invasion, proliferation, angiogenesis, and resistance to treatment. miR-1238 is upregulated in resistant GBM clones and their EVs, conferring resistance to adjacent cells via the CAV1/EGFR signaling pathway. Decrypting these mechanisms could lead to a better patient stratification and the development of novel target therapies.
Collapse
Affiliation(s)
- Andrei Buruiană
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Ștefan Ioan Florian
- Department of Neurosurgery, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (Ș.I.F.); (A.I.F.)
- Department of Neurosurgery, Emergency County Hospital, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Alexandru Ioan Florian
- Department of Neurosurgery, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (Ș.I.F.); (A.I.F.)
- Department of Neurosurgery, Emergency County Hospital, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Teodora-Larisa Timiș
- Department of Physiology, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania;
| | - Carmen Mihaela Mihu
- Department of Morphological Sciences-Histology, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania;
| | - Maria Miclăuș
- Department of Medical Genetics, Emergency Hospital for Children, 68 Moților Street, 400370 Cluj-Napoca, Romania;
| | - Sergiu Oșan
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Iona Hrapșa
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Radu Constantin Cataniciu
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Marius Farcaș
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
- Department of Genetics, IMOGEN Research Center, Louis Pasteur Street, 400349 Cluj-Napoca, Romania
| | - Sergiu Șușman
- Department of Morphological Sciences-Histology, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania;
- Department of Pathology, IMOGEN Research Center, Louis Pasteur Street, 400349 Cluj-Napoca, Romania
- Correspondence:
| |
Collapse
|
12
|
Kirichenko EY, Salah M M S, Goncharova ZA, Nikitin AG, Filippova SY, Todorov SS, Akimenko MA, Logvinov AK. Ultrastructural evidence for presenсe of gap junctions in rare case of pleomorphic xanthoastrocytoma. Ultrastruct Pathol 2020; 44:227-236. [PMID: 32148147 DOI: 10.1080/01913123.2020.1737609] [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: 10/24/2022]
Abstract
The phenomenon of unstable expression of gap junction's proteins connexins remains a "visiting card" of astrocytic tumors with various degrees of malignancy. At the same time, it stays unclear what is detected by the positive expression of connexins in astrocytic tumors: gap junctions, hemi-channels, or connexin proteins in cytosol. In the present work, for the first time, we demonstrate an ultrastructural evidence of gap junctions in pleomorphic xanthoastrocytoma, a rare primary brain tumor, the intercellular characteristics of which are poorly studied and remain very discursive and controversial. The primary tumor mass was resected during craniotomy from a 57-old patient diagnosed with pleomorphic xanthoastrocytoma Grade II based on the histopathological analysis. The immunohistochemical study was conducted with primary antibodies: Neurofilament, Myelin basic protein, Glial fibrillary acidic protein, and Synaptophysin. For electron microscopic examination fragments of tumor tissue were fixed in a glutaraldehyde, postfixed in a 1% OsO4, dehydrated and embedded into resin. After the detailed clinical, histological, and immunohistochemical study we revealed some ultrastructural characteristics of the tumor, as well as the first evidence of direct intercellular connection between the tumor cells via gap junctions. Regularly arranged gap junctions connected the somas of xanthastrocytes with dark cytoplasm containing lipid drops. Besides the localization between the cell bodies, from one to several gap junctions were found between the branches of xanthoastrocytoma in tumor intercellular space in close proximity to tumor cell. Our results may indicate gap junctions as a possible structure for intercellular communication between pleomorphic xanthoastrocytoma cells.
Collapse
Affiliation(s)
| | | | | | - Aleksei G Nikitin
- Federal Scientific and Clinical Center for Specialized Types of Medical Care and Medical Technologies FMBA of Russia, Moscow, Russian Federation
| | | | | | | | | |
Collapse
|
13
|
Song XD, Wang YN, Zhang AL, Liu B. Advances in research on the interaction between inflammation and cancer. J Int Med Res 2019; 48:300060519895347. [PMID: 31885347 PMCID: PMC7686609 DOI: 10.1177/0300060519895347] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Inflammation is the body's response to cell damage. Cancer is a general
term that describes all malignant tumours. There are no confirmed data
on cancer-related inflammation, but some research suggests that up to
50% of cancers may be linked to inflammation, which has led to the
concept of ‘cancer-associated inflammation’. Although some cancer
patients do not appear to have a chronic inflammatory background,
there might be inflammatory cell infiltration in their cancer tissues.
The continuation of the inflammatory response plays an important role
in the initiation, promotion, malignant transformation, invasion and
metastasis of cancer. Anti-inflammatory therapy has been shown to have
some effects on the prevention and treatment of cancer, which supports
a pathogenic relationship between inflammation and cancer. This review
describes the interaction between inflammation and tumour development
and the main mechanism of regulation of the inflammatory response
during tumour development.
Collapse
Affiliation(s)
- Xin-Da Song
- Department of Urinary Surgery, Graduate School of Peking Union Medical College, Beijing Hospital, National Centre of Gerontology, Beijing, China
| | - Ya-Ni Wang
- School of Basic Medical Sciences, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Ai-Li Zhang
- Department of Urinary Surgery, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Bin Liu
- Department of Urinary Surgery, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| |
Collapse
|
14
|
Zhang C, Liu CF, Chen AB, Yao Z, Li WG, Xu SJ, Ma XY. Prognostic and Clinic Pathological Value of Cx43 Expression in Glioma: A Meta-Analysis. Front Oncol 2019; 9:1209. [PMID: 31781504 PMCID: PMC6861382 DOI: 10.3389/fonc.2019.01209] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 10/23/2019] [Indexed: 12/26/2022] Open
Abstract
Gap junctional intercellular communication (GJIC) composed of connexin proteins is considered vital to cancer onset and progression since 50 years ago based on Lowenstein and Kano's works, however altered expression of connexins is still a lesser known “hallmark” of cancer. Although many studies support the hypothesis that connexins are tumor suppressors, recent evidence indicates that, in some tumor types including glioma, they may play contradictory role in some specific stages of tumor progression. We thus conduct a meta-analysis to evaluate the prognostic role of Cx43 in glioma for the unanswered questions that whether Cx43 is a beneficial or insalubrity factor for glioma. Eight studies with 1,706 patients were included for meta-analysis. The results showed that Cx43 expression was a clearly negative factor with tumor grades (I2 = 34%, P < 0.001) and beneficial for OS (n = 3, HR 2.62, 95%CI 1.47–4.68; P = 0.001). Subgroup analysis also found that Cx43 had different expression in Asian young patients vs. other groups. In conclusion, this article summarize the prognostic value of Cx43 and offer a clinical evidence for the notion that Cx43 is generally a tumor suppressor and beneficial for the patients' survival time.
Collapse
Affiliation(s)
- Chao Zhang
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China.,Brain Science Research Institute, Shandong University, Jinan, China
| | - Cheng-Fen Liu
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China
| | - An-Bin Chen
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China.,Brain Science Research Institute, Shandong University, Jinan, China
| | - Zhong Yao
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China.,Brain Science Research Institute, Shandong University, Jinan, China
| | - Wei-Guo Li
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China.,Brain Science Research Institute, Shandong University, Jinan, China
| | - Shu-Jun Xu
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China.,Brain Science Research Institute, Shandong University, Jinan, China
| | - Xiang-Yu Ma
- Department of Neurosurgery, Qilu Hospital, Shandong University, Jinan, China.,Brain Science Research Institute, Shandong University, Jinan, China
| |
Collapse
|
15
|
Brocardo L, Acosta LE, Piantanida AP, Rela L. Beneficial and Detrimental Remodeling of Glial Connexin and Pannexin Functions in Rodent Models of Nervous System Diseases. Front Cell Neurosci 2019; 13:491. [PMID: 31780897 PMCID: PMC6851021 DOI: 10.3389/fncel.2019.00491] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/17/2019] [Indexed: 01/30/2023] Open
Abstract
A variety of glial cell functions are supported by connexin and pannexin proteins. These functions include the modulation of synaptic gain, the control of excitability through regulation of the ion and neurotransmitter composition of the extracellular milieu and the promotion of neuronal survival. Connexins and pannexins support these functions through diverse molecular mechanisms, including channel and non-channel functions. The former comprise the formation of gap junction-mediated networks supported by connexin intercellular channels and the formation of pore-like membrane structures or hemichannels formed by both connexins and pannexins. Non-channel functions involve adhesion properties and the participation in signaling intracellular cascades. Pathological conditions of the nervous system such as ischemia, neurodegeneration, pathogen infection, trauma and tumors are characterized by distinctive remodeling of connexin expression and function. However, whether these changes can be interpreted as part of the pathogenesis, or as beneficial compensatory effects, remains under debate. Here we review the available evidence addressing this matter with a special emphasis in mouse models with selective manipulation of glial connexin and pannexin proteins in vivo. We postulate that the beneficial vs. detrimental effects of glial connexin remodeling in pathological conditions depend on the impact of remodeling on the different connexin and pannexin channel and non-channel functions, on the characteristics of the inflammatory environment and on the type of interaction among glial cells types.
Collapse
Affiliation(s)
- Lucila Brocardo
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Luis Ernesto Acosta
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ana Paula Piantanida
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Lorena Rela
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| |
Collapse
|
16
|
Prakoura N, Hadchouel J, Chatziantoniou C. Novel Targets for Therapy of Renal Fibrosis. J Histochem Cytochem 2019; 67:701-715. [PMID: 31116064 DOI: 10.1369/0022155419849386] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Renal fibrosis is an important component of chronic kidney disease, an incurable pathology with increasing prevalence worldwide. With a lack of available therapeutic options, end-stage renal disease is currently treated with renal replacement therapy through dialysis or transplantation. In recent years, many efforts have been made to identify novel targets for therapy of renal diseases, with special focus on the characterization of unknown mediators and pathways participating in renal fibrosis development. Using experimental models of renal disease and patient biopsies, we identified four novel mediators of renal fibrosis with potential to constitute future therapeutic targets against kidney disease: discoidin domain receptor 1, periostin, connexin 43, and cannabinoid receptor 1. The four candidates were highly upregulated in different models of renal disease and were localized at the sites of injury. Subsequent studies showed that they are centrally involved in the underlying mechanisms of renal fibrosis progression. Interestingly, inhibition of either of these proteins by different strategies, including gene deletion, antisense administration, or specific blockers, delayed the progression of renal disease and preserved renal structure and function, even when the inhibition started after initiation of the disease. This review will summarize the current findings on these candidates emphasizing on their potential to constitute future targets of therapy.
Collapse
Affiliation(s)
- Niki Prakoura
- Institut National de la Santé Et de la Recherche Médicale (INSERM) UMRS 1155, Tenon Hospital, Paris, France
| | - Juliette Hadchouel
- Institut National de la Santé Et de la Recherche Médicale (INSERM) UMRS 1155, Tenon Hospital, Paris, France.,Sorbonne Université, Paris, France
| | - Christos Chatziantoniou
- Institut National de la Santé Et de la Recherche Médicale (INSERM) UMRS 1155, Tenon Hospital, Paris, France.,Sorbonne Université, Paris, France
| |
Collapse
|
17
|
Beckmann A, Hainz N, Tschernig T, Meier C. Facets of Communication: Gap Junction Ultrastructure and Function in Cancer Stem Cells and Tumor Cells. Cancers (Basel) 2019; 11:cancers11030288. [PMID: 30823688 PMCID: PMC6468480 DOI: 10.3390/cancers11030288] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 02/22/2019] [Accepted: 02/25/2019] [Indexed: 12/28/2022] Open
Abstract
Gap junction proteins are expressed in cancer stem cells and non-stem cancer cells of many tumors. As the morphology and assembly of gap junction channels are crucial for their function in intercellular communication, one focus of our review is to outline the data on gap junction plaque morphology available for cancer cells. Electron microscopic studies and freeze-fracture analyses on gap junction ultrastructure in cancer are summarized. As the presence of gap junctions is relevant in solid tumors, we exemplarily outline their role in glioblastomas and in breast cancer. These were also shown to contain cancer stem cells, which are an essential cause of tumor onset and of tumor transmission into metastases. For these processes, gap junctional communication was shown to be important and thus we summarize, how the expression of gap junction proteins and the resulting communication between cancer stem cells and their surrounding cells contributes to the dissemination of cancer stem cells via blood or lymphatic vessels. Based on their importance for tumors and metastases, future cancer-specific therapies are expected to address gap junction proteins. In turn, gap junctions also seem to contribute to the unattainability of cancer stem cells by certain treatments and might thus contribute to therapeutic resistance.
Collapse
Affiliation(s)
- Anja Beckmann
- Department of Anatomy and Cell Biology, Saarland University, 66421 Homburg, Germany.
| | - Nadine Hainz
- Department of Anatomy and Cell Biology, Saarland University, 66421 Homburg, Germany.
| | - Thomas Tschernig
- Department of Anatomy and Cell Biology, Saarland University, 66421 Homburg, Germany.
| | - Carola Meier
- Department of Anatomy and Cell Biology, Saarland University, 66421 Homburg, Germany.
| |
Collapse
|
18
|
Involvement of Connexin Hemichannels in the Inflammatory Response of Chronic Diseases. Int J Mol Sci 2018; 19:ijms19092469. [PMID: 30134552 PMCID: PMC6164707 DOI: 10.3390/ijms19092469] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 08/18/2018] [Accepted: 08/20/2018] [Indexed: 01/08/2023] Open
|