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Pan T, Liu F, Hao X, Wang S, Wasi M, Song JH, Lewis VO, Lin PP, Moon B, Bird JE, Panaretakis T, Lin SH, Wu D, Farach-Carson MC, Wang L, Zhang N, An Z, Zhang XHF, Satcher RL. BIGH3 mediates apoptosis and gap junction failure in osteocytes during renal cell carcinoma bone metastasis progression. Cancer Lett 2024; 596:217009. [PMID: 38849015 DOI: 10.1016/j.canlet.2024.217009] [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: 03/17/2024] [Revised: 05/26/2024] [Accepted: 05/30/2024] [Indexed: 06/09/2024]
Abstract
Renal cell carcinoma (RCC) bone metastatis progression is driven by crosstalk between tumor cells and the bone microenvironment, which includes osteoblasts, osteoclasts, and osteocytes. RCC bone metastases (RCCBM) are predominantly osteolytic and resistant to antiresorptive therapy. The molecular mechanisms underlying pathologic osteolysis and disruption of bone homeostasis remain incompletely understood. We previously reported that BIGH3/TGFBI (transforming growth factor-beta-induced protein ig-h3, shortened to BIGH3 henceforth) secreted by colonizing RCC cells drives osteolysis by inhibiting osteoblast differentiation, impairing healing of osteolytic lesions, which is reversible with osteoanabolic agents. Here, we report that BIGH3 induces osteocyte apoptosis in both human RCCBM tissue specimens and in a preclinical mouse model. We also demonstrate that BIGH3 reduces Cx43 expression, blocking gap junction (GJ) function and osteocyte network communication. BIGH3-mediated GJ inhibition is blocked by the lysosomal inhibitor hydroxychloroquine (HCQ), but not osteoanabolic agents. Our results broaden the understanding of pathologic osteolysis in RCCBM and indicate that targeting the BIGH3 mechanism could be a combinational strategy for the treatment of RCCBM-induced bone disease that overcomes the limited efficacy of antiresorptives that target osteoclasts.
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Affiliation(s)
- Tianhong Pan
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Fengshuo Liu
- Departments of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Xiaoxin Hao
- Departments of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Shubo Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Murtaza Wasi
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Jian H Song
- Departments of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Valerae O Lewis
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Patrick P Lin
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Bryan Moon
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Justin E Bird
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Theocharis Panaretakis
- Departments of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Sue-Hwa Lin
- Departments of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Departments of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Danielle Wu
- Department of Diagnostic and Biomedical Sciences, The University of Texas Health Science Center at Houston, School of Dentistry, Houston, TX, USA; Departments of Bioengineering, Rice University, Houston, TX, USA
| | - Mary C Farach-Carson
- Department of Diagnostic and Biomedical Sciences, The University of Texas Health Science Center at Houston, School of Dentistry, Houston, TX, USA; Departments of BioSciences, Rice University, Houston, TX, USA; Departments of Bioengineering, Rice University, Houston, TX, USA
| | - Liyun Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Ningyan Zhang
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, USA
| | - Zhiqiang An
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, USA
| | - Xiang H-F Zhang
- Departments of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA; Departments of Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA; Departments of Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA; Departments of McNair Medical Institute, Baylor College of Medicine, Houston, TX, USA
| | - Robert L Satcher
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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Baker KM, Abt M, Doud EH, Oblak AL, Yeh ES. Mapping the Anti-Cancer Activity of α-Connexin Carboxyl-Terminal (aCT1) Peptide in Resistant HER2+ Breast Cancer. Cancers (Basel) 2024; 16:423. [PMID: 38275864 PMCID: PMC10814893 DOI: 10.3390/cancers16020423] [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: 12/20/2023] [Revised: 01/10/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024] Open
Abstract
Connexin 43 (Cx43) is a protein encoded by the GJA1 gene and is a component of cell membrane structures called gap junctions, which facilitate intercellular communication. Prior evidence indicates that elevated GJA1 expression in the HER2-positive (HER2+) subtype of breast cancer is associated with poor prognosis. Prior evidence also suggests that HER2+ breast cancers that have become refractory to HER2-targeted agents have a loss of Cx43 gap junction intercellular communication (GJIC). In this study, a Cx43-targeted agent called alpha-connexin carboxyl-terminal peptide (aCT1) is examined to determine whether GJIC can be rescued in refractory HER2+ breast cancer cells. A proposed mechanism of action for aCT1 is binding to the tight junction protein Zonal Occludens-1 (ZO-1). However, the true scope of activity for aCT1 has not been explored. In this study, mass spectrometry proteomic analysis is used to determine the breadth of aCT1-interacting proteins. The NanoString nCounter Breast Cancer 360 panel is also used to examine the effect of aCT1 on cancer signaling in HER2+ breast cancer cells. Findings from this study show a dynamic range of binding partners for aCT1, many of which regulate gene expression and RNA biology. nCounter analysis shows that a number of pathways are significantly impacted by aCT1, including upregulation of apoptotic factors, leading to the prediction and demonstration that aCT1 can boost the cell death effects of cisplatin and lapatinib in HER2+ breast cancer cells that have become resistant to HER2-targeted agents.
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Affiliation(s)
- Kimberly M. Baker
- Department of Biology, University of Indianapolis, Indianapolis, IN 46227, USA;
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Melissa Abt
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Emma H. Doud
- Melvin and Bren Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Adrian L. Oblak
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Elizabeth S. 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;
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Abu Bakar NFAB, Yeo ZL, Hussin F, Madhavan P, Lim V, Jemon K, Prabhakaran P. Synergistic effects of combined cisplatin and Clinacanthus nutans extract on triple negative breast cancer cells. J Taibah Univ Med Sci 2023; 18:1220-1236. [PMID: 37250812 PMCID: PMC10209459 DOI: 10.1016/j.jtumed.2023.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 02/18/2023] [Accepted: 04/05/2023] [Indexed: 05/31/2023] Open
Abstract
Objective Triple negative breast cancer (TNBC) is the most invasive breast cancer subtype enriched with cancer stem cells. TNBCs do not express estrogen, progesterone, or human epidermal growth factor receptor 2 (HER2) receptors, making them difficult to be targeted by existing chemotherapy treatments. In this study, we attempted to identify the effects of combined cisplatin and Clinacanthus nutans treatment on MDA-MD-231 and MDA-MB-468 breast cancer cells, which represent TNBC subtypes. Methods The phytochemical fingerprint of C. nutans ethanolic leaf extract was evaluated by LC-MS/MS analysis. We investigated the effects of cisplatin (0-15.23 μg/mL), C. nutans (0-50 μg/mL), and a combination of cisplatin (3.05 μg/mL) and C. nutans (0-50 μg/mL), on cell viability, proliferation, apoptosis, invasion, mRNA expression in cancer stem cells (CD49f, KLF4), and differentiation markers (TUBA1A, KRT18) in TNBC cells. In addition, we also studied the interaction between cisplatin and C. nutans. Results Derivatives of fatty acids, carboxylic acid ester, and glycosides, were identified as the major bioactive compounds with potential anticancer properties in C. nutans leaf extract. Reductions in cell viability (0-78%) and proliferation (2-77%), as well as a synergistic anticancer effect, were identified in TNBC cells when treated with a combination of cisplatin and C. nutans. Furthermore, apoptotic induction via increased caspase-3/7 activity (MDA-MB-231: 2.73-fold; MDA-MB-468: 3.53-fold), and a reduction in cell invasion capacity to 36%, were detected in TNBC cells when compared to single cisplatin and C. nutans treatments. At the mRNA level, cisplatin and C. nutans differentially regulated specific genes that are responsible for proliferation and differentiation. Conclusion Our findings demonstrate that the combination of cisplatin and C. nutans represents a potential treatment for TNBC.
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Affiliation(s)
| | - Zhin Leng Yeo
- Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Malaysia
| | - Faisal Hussin
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Malaysia
| | - Priya Madhavan
- School of Medicine, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Malaysia
| | - Vuanghao Lim
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Penang, Malaysia
| | - Khairunadwa Jemon
- Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Malaysia
| | - Praseetha Prabhakaran
- Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Malaysia
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Li X, Xiao Y, Wang X, Huang R, Wang R, Deng Y, Rao J, Gao Q, Yang S, Zhang X. Connexin 43-modified bone marrow stromal cells reverse the imatinib resistance of K562 cells via Ca 2+ -dependent gap junction intercellular communication. Chin Med J (Engl) 2023; 136:194-206. [PMID: 36801891 PMCID: PMC10106204 DOI: 10.1097/cm9.0000000000002554] [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: 07/27/2022] [Indexed: 02/23/2023] Open
Abstract
BACKGROUND Imatinib mesylate (IM) resistance is an emerging problem for chronic myeloid leukemia (CML). Previous studies found that connexin 43 (Cx43) deficiency in the hematopoietic microenvironment (HM) protects minimal residual disease (MRD), but the mechanism remains unknown. METHODS Immunohistochemistry assays were employed to compare the expression of Cx43 and hypoxia-inducible factor 1α (HIF-1α) in bone marrow (BM) biopsies of CML patients and healthy donors. A coculture system of K562 cells and several Cx43-modified bone marrow stromal cells (BMSCs) was established under IM treatment. Proliferation, cell cycle, apoptosis, and other indicators of K562 cells in different groups were detected to investigate the function and possible mechanism of Cx43. We assessed the Ca 2+ -related pathway by Western blotting. Tumor-bearing models were also established to validate the causal role of Cx43 in reversing IM resistance. RESULTS Low levels of Cx43 in BMs were observed in CML patients, and Cx43 expression was negatively correlated with HIF-1α. We also observed that K562 cells cocultured with BMSCs transfected with adenovirus-short hairpin RNA of Cx43 (BMSCs-shCx43) had a lower apoptosis rate and that their cell cycle was blocked in G0/G1 phase, while the result was the opposite in the Cx43-overexpression setting. Cx43 mediates gap junction intercellular communication (GJIC) through direct contact, and Ca 2+ is the key factor mediating the downstream apoptotic pathway. In animal experiments, mice bearing K562, and BMSCs-Cx43 had the smallest tumor volume and spleen, which was consistent with the in vitro experiments. CONCLUSIONS Cx43 deficiency exists in CML patients, promoting the generation of MRD and inducing drug resistance. Enhancing Cx43 expression and GJIC function in the HM may be a novel strategy to reverse drug resistance and promote IM efficacy.
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Affiliation(s)
- Xiaoping Li
- Department of Hematology, 920th Hospital of Joint Logistic Support Force of People's Liberation, Kunming, Yunnan 650000, China
| | - Yunshuo Xiao
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Xiaoqi Wang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Ruihao Huang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Rui Wang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Yi Deng
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Jun Rao
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Qiangguo Gao
- Department of Cell Biology College of Basic Medicine, Army Medical University, Chongqing 400038, China
| | - Shijie Yang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
| | - Xi Zhang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burn and Combined Injury, Army Medical University, Chongqing 400037, China
- Jinfeng Laboratory, Chongqing 401329, China
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Ugur D, Gungul TB, Yucel S, Ozcivici E, Yalcin-Ozuysal O, Mese G. Connexin 32 overexpression increases proliferation, reduces gap junctional intercellular communication, motility and epithelial-to-mesenchymal transition in Hs578T breast cancer cells. J Cell Commun Signal 2022; 16:361-376. [PMID: 35781670 DOI: 10.1007/s12079-021-00665-9] [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: 04/01/2021] [Accepted: 12/14/2021] [Indexed: 11/29/2022] Open
Abstract
Connexins (Cx) are primary components of gap junctions that selectively allow molecules to be exchanged between adjacent cells, regulating multiple cellular functions. Along with their channel forming functions, connexins play a variety of roles in different stages of tumorigenesis and their roles in tumor initiation and progression is isoform- and tissue-specific. While Cx26 and Cx43 were downregulated during breast tumorigenesis, Cx32 was accumulated in the cytoplasm of the cells in lymph node metastasis of breast cancers and Cx32 was further upregulated in metastasis. Cx32's effect on cell proliferation, gap junctional communication, hemichannel activity, cellular motility and epithelial-to-mesenchymal transition (EMT) were investigated by overexpressing Cx32 in Hs578T and MCF7 breast cancer cells. Additionally, the expression and localization of Cx26 and Cx43 upon Cx32 overexpression were examined by Western blot and immunostaining experiments, respectively. We observed that MCF7 cells had endogenous Cx32 while Hs578T cells did not and when Cx32 was overexpressed in these cells, it caused a significant increase in the percentages of Hs578T cells at the S phase in addition to increasing their proliferation. Further, while Cx32 overexpression did not induce hemichannel activity in either cell, it decreased gap junctional communication between Hs578T cells. Additionally, Cx32 was mainly observed in the cytoplasm in both cells, where it did not form gap junction plaques but Cx32 overexpression reduced Cx43 levels without affecting Cx26. Moreover, migration and invasion potentials of Hs578T and migration in MCF7 were reduced upon Cx32 overexpression. Finally, the protein level of mesenchymal marker N-cadherin decreased while epithelial marker ZO-1 and E-cadherin increased in Hs578T cells. We observed that Cx32 overexpression altered cell proliferation, communication, migration and EMT in Hs578T, suggesting a tumor suppressor role in these cells while it had minor effects on MCF7 cells.
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Affiliation(s)
- Deniz Ugur
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, 35430, Turkey.,Department of Molecular Biology and Genetics, Avrasya University, Trabzon, Turkey
| | - Taha Bugra Gungul
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, 35430, Turkey
| | - Simge Yucel
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, 35430, Turkey
| | - Engin Ozcivici
- Department of Bioengineering, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Ozden Yalcin-Ozuysal
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, 35430, Turkey
| | - Gulistan Mese
- Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, 35430, Turkey.
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Zhu D, Feng L, Feliu N, Guse AH, Parak WJ. Stimulation of Local Cytosolic Calcium Release by Photothermal Heating for Studying Intra- and Intercellular Calcium Waves. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2008261. [PMID: 33949733 DOI: 10.1002/adma.202008261] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/16/2021] [Indexed: 06/12/2023]
Abstract
A methodology is described that allows for localized Ca2+ release by photoexcitation. For this, cells are loaded with polymer capsules with integrated plasmonic nanoparticles, which reside in endo-lysosomes. The micrometer-sized capsules can be individually excited by near-infrared light from a light pointer, causing photothermal heating, upon which there is a rise in the free cytosolic Ca2+ concentration ([Ca2+ ]i ). The [Ca2+ ]i can be analyzed with a Ca2+ indicator fluorophore. In this way, it is possible to excite local lysosomal Ca2+ release in a desired target cell.
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Affiliation(s)
- Dingcheng Zhu
- Fachbereich Physik, CHyN, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
- College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Yuhangtang road 2318, Hangzhou, 311121, China
| | - Lili Feng
- Fachbereich Physik, CHyN, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Neus Feliu
- Fachbereich Physik, CHyN, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
- CAN, Fraunhofer Institut, Grindelallee 117, 20146, Hamburg, Germany
| | - Andreas H Guse
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Wolfgang J Parak
- Fachbereich Physik, CHyN, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
- National Engineering Center for Nanotechnology (NECN), Shanghai Jiao Tong University, Dongchuan road 800, Shanghai, 200240, China
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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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Zhang J, Wang X, Hou Z, Neng L, Cai J, Zhang Y, Shi X. Suppression of Connexin 43 Leads to Strial Vascular Hyper-Permeability, Decrease in Endocochlear Potential, and Mild Hearing Loss. Front Physiol 2020; 11:974. [PMID: 32922309 PMCID: PMC7457066 DOI: 10.3389/fphys.2020.00974] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/16/2020] [Indexed: 12/20/2022] Open
Abstract
Objective: Connexin 43 (Cx43) is a protein constituent of gap junctions (GJs) in various barrier cells, especially astrocytes and microglia of the blood-brain-barrier (BBB), where it plays an important role in intercellular communication and regulation of the barrier. Despite the importance of Cx43 in other blood barriers, not much attention has been paid to expression and function of Cx43 in the blood-labyrinth-barrier (BLB) of the stria vascularis in the cochlea. Methods: We used multiple research approaches, including immunocytochemical staining, patch-clamp dye loading technique, real-time quantitative reverse transcription (RT)-PCR, western blot, measurement of endocochlear potential (EP) with an electrode through the scala media, and auditory brainstem response to test hearing function. Results: We found Cx43 expressed in vascular endothelial cells (ECs) and perivascular resident macrophages (PVMs) in the stria vascularis of adult C57BL/6 mouse cochleae. In particular, we found Cx43 expressed in foot processes of PVMs at points of contact with the endothelium. Consistent with Cx43 expression in vivo, we also found Cx43 expressed in EC-EC and EC-PVM interfaces in a co-cultured cell line model. Using a patch-clamp dye loading technique, we demonstrated that Alexa Fluor® 568 dye injected into PVMs diffuses to connected neighboring ECs. The functional coupling between the ECs and PVMs is blocked by 18α-Glycyrrhetinic acid (18α-GA), a GJ blocker. Suppression of Cx43 with small interfering RNA (siRNA) in vivo significantly elevated hearing threshold and caused the EP to drop and the blood barrier to become more permeable. In further study, using in vitro primary EC cell line models, we demonstrated that suppression of Cx43 disrupts intercellular tight junctions (TJs) in the EC monolayer and increases endothelial monolayer permeability. Conculsion: Taken together, these findings underscore the importance of Cx43 expression in the normal ear for maintaining BLB integrity, normal EP, and hearing function.
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Affiliation(s)
- Jinhui Zhang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Xiaohan Wang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
- Boston Children’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Zhiqiang Hou
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Lingling Neng
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Jing Cai
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Yunpei Zhang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Xiaorui Shi
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
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Sinha G, Ferrer AI, Moore CA, Naaldijk Y, Rameshwar P. Gap Junctions and Breast Cancer Dormancy. Trends Cancer 2020; 6:348-357. [PMID: 32209448 DOI: 10.1016/j.trecan.2020.01.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/21/2022]
Abstract
Breast cancer (BC) relapse, despite clinical advancement, remains one of the biggest issues in the field. Intercellular communication, specifically via connexin (Cx)-mediated gap junctions (GJs), play a key role in the long-term survival of these, treatment-resistant breast cancer stem cells (CSCs), allowing for relapse. Both basic and clinical evidence reveal dual roles for GJs, in tumor suppression, generally referred to as dormancy, and progression and metastasis. GJ intercellular communication (GJIC) can be mediated by multiple types of Cxs, depending on the organ to which the BC cells metastasize. This review expands on the differential expression of Cx-mediated GJIC between CSCs and niche cells within a given microenvironment.
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Affiliation(s)
- Garima Sinha
- Rutgers School of Graduate Studies at New Jersey Medical School, Newark, NJ, USA; Department of Medicine - Hematology/Oncology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Alejandra I Ferrer
- Rutgers School of Graduate Studies at New Jersey Medical School, Newark, NJ, USA; Department of Medicine - Hematology/Oncology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Caitlyn A Moore
- Rutgers School of Graduate Studies at New Jersey Medical School, Newark, NJ, USA; Department of Medicine - Hematology/Oncology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Yahaira Naaldijk
- Rutgers School of Graduate Studies at New Jersey Medical School, Newark, NJ, USA
| | - Pranela Rameshwar
- Department of Medicine - Hematology/Oncology, Rutgers New Jersey Medical School, Newark, NJ, USA.
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10
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Activation of Src mediates acquired cisplatin resistance in human lung carcinoma cells. Anticancer Drugs 2019; 31:123-130. [PMID: 31815763 DOI: 10.1097/cad.0000000000000829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cisplatin (CDDP) is the most effective chemotherapeutic drug against lung carcinoma. However, the emergence of resistant clones has severely limited its clinical application. We found that the cisplatin-resistant lung carcinoma cell line A549/CDDP had increased levels of the phosphorylated gap junction protein Cx43 and SRC tyrosine kinase, and low levels of total Cx43 protein and reduced gap junction formation. The SRC kinase inhibitor PP2 increased the expression of total Cx43 protein and enhanced cisplatin sensitivity, indicating that activated SRC kinase induces chemoresistance by decrease total Cx43 level. Furthermore, Cx43 gene silencing in the drug-resistant cell lines abrogated the sensitizing effect of PP2. Taken together, targeting SRC kinase by PP2 reverses cisplatin resistance by upregulating Cx43 protein levels, indicating a novel pathway of cisplatin resistance that may be amenable to therapeutic intervention.
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王 道, 刘 亚, 赵 婉, 王 茹, 童 旭, 蒋 国. [SRC kinase inhibitor PP2 inhibits invasion and metastasis of lung cancer A549 cells by upregulating connexin43 expression]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2019; 39:797-803. [PMID: 31340912 PMCID: PMC6765555 DOI: 10.12122/j.issn.1673-4254.2019.07.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the effect of SRC kinase inhibitor PP2 on the invasion and metastasis of lung cancer A549 cells and explore its molecular mechanism. METHODS MTT assay was used to evaluate the inhibitory effect of PP2 on the proliferation of A549 cells. Cell scratch and Transwell assays were performed to assess the invasion and metastatic capacity of A549 cells after treatment with 1, 2, 4, 8, and 16 μmol/L PP2 for 24 h. Western blotting was used to detect the expressions of connexin43 (Cx43) and MMP-2 in the cells after small interfering RNA (siRNA)-mediated silencing or overexpression of Cx43; the changes in the cell invasion and metastasis in response to PP2 treatment after Cx43 silencing or overexpression were investigated. RESULTS MTT assay showed that treatment with PP2 at 2, 4, 8, 16, and 32 μmol/L significantly inhibited the proliferation of A549 cells in a concentration-dependent manner. Treatments with PP2 at 1, 2, 4, 8, and 16 μmol/L for 24 h also concentration-dependently lowered the invasion and metastatic abilities of the cells (P < 0.05). At 4 and 8 μmol/L, PP2 significantly increased the expression level of Cx43 protein and decreased the expression level of MMP-2 protein. Overexpression of Cx43 significantly enhanced the inhibitory effect of PP2 on the cell invasion and metastasis, and Cx43 silencing significantly attenuated the inhibitory effect of PP2 (P < 0.05). CONCLUSIONS PP2 treatment can suppress the invasion and metastasis of A549 cells in vitro possibly by modulating the expression of Cx43.
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Affiliation(s)
- 道鑫 王
- />蚌埠医学院药学院药理教研室//安徽省生化药物工程技术研究中心,安徽 蚌埠 233030School of Pharmacy, Bengbu Medical College/Anhui Engineering Technology Research Center of Biochemical Pharmaceuticals, Bengbu 233030, China
| | - 亚明 刘
- />蚌埠医学院药学院药理教研室//安徽省生化药物工程技术研究中心,安徽 蚌埠 233030School of Pharmacy, Bengbu Medical College/Anhui Engineering Technology Research Center of Biochemical Pharmaceuticals, Bengbu 233030, China
| | - 婉晨 赵
- />蚌埠医学院药学院药理教研室//安徽省生化药物工程技术研究中心,安徽 蚌埠 233030School of Pharmacy, Bengbu Medical College/Anhui Engineering Technology Research Center of Biochemical Pharmaceuticals, Bengbu 233030, China
| | - 茹 王
- />蚌埠医学院药学院药理教研室//安徽省生化药物工程技术研究中心,安徽 蚌埠 233030School of Pharmacy, Bengbu Medical College/Anhui Engineering Technology Research Center of Biochemical Pharmaceuticals, Bengbu 233030, China
| | - 旭辉 童
- />蚌埠医学院药学院药理教研室//安徽省生化药物工程技术研究中心,安徽 蚌埠 233030School of Pharmacy, Bengbu Medical College/Anhui Engineering Technology Research Center of Biochemical Pharmaceuticals, Bengbu 233030, China
| | - 国君 蒋
- />蚌埠医学院药学院药理教研室//安徽省生化药物工程技术研究中心,安徽 蚌埠 233030School of Pharmacy, Bengbu Medical College/Anhui Engineering Technology Research Center of Biochemical Pharmaceuticals, Bengbu 233030, China
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12
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Pro-Apoptotic Effect of Grape Seed Extract on MCF-7 Involves Transient Increase of Gap Junction Intercellular Communication and Cx43 Up-Regulation: A Mechanism of Chemoprevention. Int J Mol Sci 2019; 20:ijms20133244. [PMID: 31269652 PMCID: PMC6651466 DOI: 10.3390/ijms20133244] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023] Open
Abstract
Growing evidence suggests dietary antioxidants reduce the risk of several cancers. Grape seeds extracts (GSE) are a rich source of polyphenols known to have antioxidant, chemopreventive and anticancer properties. Herein, we investigated the in vitro effects and putative action mechanisms of a grape seed extract (GSE) on human breast cancer cells (MCF-7). The effects of GSE were evaluated on cell proliferation, apoptosis and gap-junction-mediated cell-cell communications (GJIC), as basal mechanism involved in the promotion stage of carcinogenesis. GSE (0.05-100 μg/mL) caused a significant dose- and time-dependent inhibition of MCF-7 viability and induced apoptotic cell death, as detected by Annexin-V/Propidium Iodide. Concurrently, GSE induced transient but significant enhancement of GJIC in non-communicating MCF-7 cells, as demonstrated by the scrape-loading/dye-transfer (SL/DT) assay and an early and dose-dependent re-localization of the connexin-43 (Cx43) proteins on plasma membranes, as assayed by immunocytochemistry. Finally, real-time-PCR has evidenced a significant increase in cx43 mRNA expression. The results support the hypothesis that the proliferation inhibition and pro-apoptotic effect of GSE against this breast cancer cell model are mediated by the GJIC improvement via re-localization of Cx43 proteins and up-regulation of cx43 gene, and provide further insight into the action mechanisms underlying the health-promoting action of dietary components.
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Huang BR, Tsai CH, Chen CC, Way TD, Kao JY, Liu YS, Lin HY, Lai SW, Lu DY. Curcumin Promotes Connexin 43 Degradation and Temozolomide-Induced Apoptosis in Glioblastoma Cells. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2019; 47:657-674. [PMID: 30974966 DOI: 10.1142/s0192415x19500344] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glioblastoma (GBM) is the most commonly occurring tumor in the cerebral hemispheres. Currently, temozolomide (TMZ), an alkylating agent that induces DNA strand breaks, is considered the frontline chemotherapeutic agent for GBM. Despite its frontline status, GBM patients commonly exhibit resistance to TMZ treatment. We have recently established and characterized TMZ-resistant human glioma cells. The aim of this study is to investigate whether curcumin modulates cell apoptosis through the alternation of the connexin 43 (Cx43) protein level in TMZ-resistant GBM. Overexpression of Cx43, but not ATP-binding cassette transporters (ABC transporters), was observed (approximately 2.2-fold) in TMZ-resistant GBM cells compared to the Cx43 levels in parental GBM cells. Furthermore, at a concentration of 10 μ M, curcumin significantly reduced Cx43 protein expression by about 40%. In addition, curcumin did not affect the expression of other connexins like Cx26 or epithelial-to-mesenchymal transition (EMT) proteins such as β -catenin or α E-catenin. Curcumin treatment led to an increase in TMZ-induced cell apoptosis from 4% to 8%. Importantly, it did not affect the mRNA expression level of Cx43. Concomitant treatment with the translation inhibitor cycloheximide (CHX) exerted additional effects on Cx43 degradation. Treatment with the autophagy inhibitor 3-MA (methyladenine) did not affect the curcumin-induced Cx43 degradation. Interestingly, treatment with the proteasome inhibitor MG132 (carbobenzoxy-Leu-Leu-leucinal) significantly negated the curcumin-induced Cx43 degradation, which suggests that curcumin-induced Cx43 degradation occurs through the ubiquitin-proteasome pathway.
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Affiliation(s)
- Bor-Ren Huang
- * Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan.,¶ Department of Neurosurgery, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan.,∥ School of Medicine, Tzu Chi University, Taichung, Taiwan
| | - Chon-Haw Tsai
- ** Department of Neurology, China Medical University Hospital, Taichung, Taiwan
| | - Chun-Chuan Chen
- †† Institute of Biochemistry, College of Life Science, National Chung Hsing University, Taichung, Taiwan
| | - Tzong-Der Way
- † Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung, Taiwan
| | - Jung-Yie Kao
- †† Institute of Biochemistry, College of Life Science, National Chung Hsing University, Taichung, Taiwan
| | - Yu-Shu Liu
- ‡ Department of Pharmacology, School of Medicine, China Medical University, Taichung, Taiwan
| | - Hsiao-Yun Lin
- ‡ Department of Pharmacology, School of Medicine, China Medical University, Taichung, Taiwan
| | - Sheng-Wei Lai
- § Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan
| | - Dah-Yuu Lu
- ‡ Department of Pharmacology, School of Medicine, China Medical University, Taichung, Taiwan.,‡‡ Department of Photonics and Communication Engineering, Asia University, Taichung, Taiwan
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蒋 国, 刘 亚, 赵 婉, 王 道, 董 淑, 童 旭. [Effect of gap junction modulation on antitumor effects of adriamycin in estrogen receptor-positive breast cancer cells]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:780-786. [PMID: 33168517 PMCID: PMC6765543 DOI: 10.3969/j.issn.1673-4254.2018.07.02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To observe the effect of functional modulation of gap junctions (GJ) on the antitumor effect of adriamycin in breast cancer cells positive for estrogen receptor (ER). METHODS The inhibitory effect of 0 to 24.0 μmol/L adriamycin on the surviving fraction of ER-positive human breast cancer MCF-7 cells and ER-negative MDA-MB-231 cells was assessed with MTT assay; Western blotting and immunofluorescence assay were used to detect the expressions of Cx43 total protein and membrane protein in the cells. A parachute assay was used to evaluate the function of the GJ in MCF-7 cells. The cytotoxic effect of adriamycin was observed in the cells treated with retinoic acid (RA) for enhancing GJ function, in cells treated with oleamide and 18-α- glycyrrhizic acid (18-α-ga) for inhibiting GJ function, and also in cells transfected with Cx43siRNA for Cx43 knockdown. RESULTS ER-positive MCF-7 cells expressed a significantly higher level of Cx43 with stronger GJ function than ER-negative MDA- MB-231 cells. Adriamycin significantly inhibited the proliferation of MCF-7 cells (P < 0.01), and RA treatment further increased the cytotoxicity of adriamycin (P < 0.01) while oleamide and 18-α-GA obviously attenuated the cytotoxicity of adriamycin (P < 0.01). In the cells with Cx43 knockdown, the expressions of total Cx43 protein and Cx43 on the membrane were significantly reduced, the function of GJ was attenuated, and the cytotoxicity of adriamycin was significantly decreased (P < 0.01). CONCLUSIONS ER-positive breast cancer cells have stronger Cx43 expressions and GJ function than the ERnegative cells. The cytotoxicity of adriamycin against the breast cancer cells can be strengthened by enhancing GJ function and attenuated by inhibiting GJ function. Cx43 silencing inhibits the function of GJ to lower the cytotoxicity of adriamycin in human breast cancer MCF-7 cells.
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Affiliation(s)
- 国君 蒋
- />蚌埠医学院药学院药理教研室,安徽 蚌埠 233030Pharmacology department of Bengbu Medical college, Bengbu 233030, China
| | - 亚明 刘
- />蚌埠医学院药学院药理教研室,安徽 蚌埠 233030Pharmacology department of Bengbu Medical college, Bengbu 233030, China
| | - 婉晨 赵
- />蚌埠医学院药学院药理教研室,安徽 蚌埠 233030Pharmacology department of Bengbu Medical college, Bengbu 233030, China
| | - 道鑫 王
- />蚌埠医学院药学院药理教研室,安徽 蚌埠 233030Pharmacology department of Bengbu Medical college, Bengbu 233030, China
| | - 淑英 董
- />蚌埠医学院药学院药理教研室,安徽 蚌埠 233030Pharmacology department of Bengbu Medical college, Bengbu 233030, China
| | - 旭辉 童
- />蚌埠医学院药学院药理教研室,安徽 蚌埠 233030Pharmacology department of Bengbu Medical college, Bengbu 233030, China
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15
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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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16
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Mensah SA, Cheng MJ, Homayoni H, Plouffe BD, Coury AJ, Ebong EE. Regeneration of glycocalyx by heparan sulfate and sphingosine 1-phosphate restores inter-endothelial communication. PLoS One 2017; 12:e0186116. [PMID: 29023478 PMCID: PMC5638341 DOI: 10.1371/journal.pone.0186116] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 09/25/2017] [Indexed: 11/18/2022] Open
Abstract
Vasculoprotective endothelium glycocalyx (GCX) shedding plays a critical role in vascular disease. Previous work demonstrated that GCX degradation disrupts endothelial cell (EC) gap junction connexin (Cx) proteins, likely blocking interendothelial molecular transport that maintains EC and vascular tissue homeostasis to resist disease. Here, we focused on GCX regeneration and tested the hypothesis that vasculoprotective EC function can be stimulated via replacement of GCX when it is shed. We used EC with [i] intact heparan sulfate (HS), the most abundant GCX component; [ii] degraded HS; or [iii] HS that was restored after enzyme degradation, by cellular self-recovery or artificially. Artificial HS restoration was achieved via treatment with exogenous HS, with or without the GCX regenerator and protector sphingosine 1- phosphate (S1P). In these cells we immunocytochemically examined expression of Cx isotype 43 (Cx43) at EC borders and characterized Cx-containing gap junction activity by measuring interendothelial spread of gap junction permeable Lucifer Yellow dye. With intact HS, 60% of EC borders expressed Cx43 and dye spread to 2.88 ± 0.09 neighboring cells. HS degradation decreased Cx43 expression to 30% and reduced dye spread to 1.87± 0.06 cells. Cellular self-recovery of HS restored baseline levels of Cx43 and dye transfer. Artificial HS recovery with exogenous HS partially restored Cx43 expression to 46% and yielded dye spread to only 1.03 ± 0.07 cells. Treatment with both HS and S1P, recovered HS and restored Cx43 to 56% with significant dye transfer to 3.96 ± 0.23 cells. This is the first evidence of GCX regeneration in a manner that effectively restores vasculoprotective EC communication.
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Affiliation(s)
- Solomon A. Mensah
- Department of Bioengineering, Northeastern University, Boston, Massachusetts, United States of America
| | - Ming J. Cheng
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, United States of America
| | - Homa Homayoni
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, United States of America
| | - Brian D. Plouffe
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, United States of America
| | - Arthur J. Coury
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, United States of America
| | - Eno E. Ebong
- Department of Bioengineering, Northeastern University, Boston, Massachusetts, United States of America
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, United States of America
- Department of Neuroscience, Albert Einstein College of Medicine, New York, New York, United States of America
- * E-mail:
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