1
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Maharjan S, Kirk RS, Lawton SP, Walker AJ. Human growth factor-mediated signalling through lipid rafts regulates stem cell proliferation, development and survival of Schistosoma mansoni. Open Biol 2024; 14:230262. [PMID: 38195062 PMCID: PMC10776228 DOI: 10.1098/rsob.230262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/16/2023] [Indexed: 01/11/2024] Open
Abstract
Although the mechanisms by which schistosomes grow and develop in humans are poorly defined, their unique outer tegument layer, which interfaces with host blood, is considered vital to homeostasis of the parasite. Here, we investigated the importance of tegument lipid rafts to the biology of Schistosoma mansoni in the context of host-parasite interactions. We demonstrate the temporal clustering of lipid rafts in response to human epidermal growth factor (EGF) during early somule development, concomitant with the localization of anteriorly orientated EGF receptors (EGFRs) and insulin receptors, mapped using fluorescent EGF/insulin ligand. Methyl-β-cyclodextrin (MβCD)-mediated depletion of cholesterol from lipid rafts abrogated the EGFR/IR binding at the parasite surface and led to modulation of protein kinase C, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase and Akt signalling pathways within the parasite. Furthermore, MβCD-mediated lipid raft disruption, and blockade of EGFRs using canertinib, profoundly reduced somule motility and survival, and attenuated stem cell proliferation and somule growth and development particularly to the fast-growing liver stage. These findings provide a novel paradigm for schistosome development and vitality in the host, driven through host-parasite interactions at the tegument, that might be exploitable for developing innovative therapeutic approaches to combat human schistosomiasis.
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Affiliation(s)
- Shradha Maharjan
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
| | - Ruth S. Kirk
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
| | - Scott P. Lawton
- Centre for Epidemiology and Planetary Health, SRUC School of Veterinary Medicine, Scotland's Rural College, West Mains Road, Edinburgh EH9 3JG, UK
| | - Anthony J. Walker
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
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2
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Chen T, Tang X, Wang Z, Feng F, Xu C, Zhao Q, Wu Y, Sun H, Chen Y. Inhibition of Son of Sevenless Homologue 1 (SOS1): Promising therapeutic treatment for KRAS-mutant cancers. Eur J Med Chem 2023; 261:115828. [PMID: 37778239 DOI: 10.1016/j.ejmech.2023.115828] [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: 07/04/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/03/2023]
Abstract
Kristen rat sarcoma (KRAS) is one of the most common oncogenes in human cancers. As a guanine nucleotide exchange factor, Son of Sevenless Homologue 1 (SOS1) represents a potential therapeutic concept for the treatment of KRAS-mutant cancers because of its activation on KRAS and downstream signaling pathways. In this review, we provide a comprehensive overview of the structure, biological function, and regulation of SOS1. We also focus on the recent advances in SOS1 inhibitors and emphasize their binding modes, structure-activity relationships and pharmacological activities. We hope that this publication can provide a comprehensive compendium on the rational design of SOS1 inhibitors.
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Affiliation(s)
- Tingkai Chen
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, People's Republic of China
| | - Xu Tang
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, People's Republic of China
| | - Zhenqi Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Feng Feng
- School of Pharmacy, Nanjing Medical University, 211166, Nanjing, People's Republic of China
| | - Chunlei Xu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Qun Zhao
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Yulan Wu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China
| | - Haopeng Sun
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, People's Republic of China.
| | - Yao Chen
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China.
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3
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Luo G, Wang B, Hou Q, Wu X. Development of Son of Sevenless Homologue 1 (SOS1) Modulators To Treat Cancers by Regulating RAS Signaling. J Med Chem 2023; 66:4324-4341. [PMID: 36987571 DOI: 10.1021/acs.jmedchem.2c01729] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Son of sevenless homologue 1 (SOS1) protein is universally expressed in cells and plays an important role in the RAS signaling pathway. Specifically, this protein interacts with RAS in response to upstream stimuli to promote guanine nucleotide exchange in RAS and activates the downstream signaling pathways. Thus, targeting SOS1 is a new approach for treating RAS-driven cancers. In this Perspective, we briefly summarize the structural and functional aspects of SOS1 and focus on recent advances in the discovery of activators, inhibitors, and PROTACs that target SOS1. This review aims to provide a timely and updated overview on the strategies for targeting SOS1 in cancer therapy.
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Affiliation(s)
- Guangmei Luo
- Department of Medicinal Chemistry, School of Pharmacy and Institute of Innovative Drug Discovery and Development, China Pharmaceutical University, Nanjing 211198, China
| | - Bingrui Wang
- Department of Medicinal Chemistry, School of Pharmacy and Institute of Innovative Drug Discovery and Development, China Pharmaceutical University, Nanjing 211198, China
| | - Qiangqiang Hou
- Department of Medicinal Chemistry, School of Pharmacy and Institute of Innovative Drug Discovery and Development, China Pharmaceutical University, Nanjing 211198, China
| | - Xiaoxing Wu
- Department of Medicinal Chemistry, School of Pharmacy and Institute of Innovative Drug Discovery and Development, China Pharmaceutical University, Nanjing 211198, China
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4
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Fan Z, Li M, Xu Y, Ge C, Gu J. EPS8L3 promotes pancreatic cancer proliferation and metastasis by activating GSK3B. J Med Biochem 2023; 42:105-112. [PMID: 36819133 PMCID: PMC9920878 DOI: 10.5937/jomb0-38840] [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: 05/12/2022] [Accepted: 07/11/2022] [Indexed: 11/02/2022] Open
Abstract
Background We intended to investigate the role and regulatory mechanism of EPS8L3 in increase the development of pancreatic cancer (PC). Methods In order to analyze the relationship between EPS8L3 level and clinicopathological indicators of PC patients, qRT-PCR was used to detect the expression of EPS8L3 in tumor specimens of 40 PC patients. EPS8L3 knockdown models were then constructed in PC cell lines. Furthermore, the effect of EPS8L3 on PC cell function was analyzed by CCK-8 and Transwell assay. Dual luciferase reporter gene assay and recovery assay were used to further investigate the underlying mechanism. Results qRT-PCR results indicated that EPS8L3 was highly expressed in PC tissues compared with adjacent ones. At the same time, the incidence of distant metastasis was higher in PC patients with high EPS8L3 level. In vitro analysis such as CCK-8 and Transwell experimentations indicated that knockdown of EPS8L3 markedly inhibited the proliferative and metastatic ability. Bio-informatics together with luciferase report assay proposing that EPS8L3 can target GSK3B. Western Blot results revealed that knockdown of EPS8L3 markedly reduced the GSK3B expression in PC cells, and there was a positively associated between the two in PC cells. In addition, the recovery experimentation proved that EPS8L3 and GSK3B have a mutual regulation effect. Overexpression of GSK3B can reversal the prohibitive effect of EPS8L3 knockdown on the malignant development of PC cells, thereby jointly regulating the occurrence and development of PC. Conclusions EPS8L3 promotes the development of PC by regulating GSK3B, suggesting that EPS8L3 can be used as a biomarker for early diagnosis and treatment of PC.
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Affiliation(s)
- Zun Fan
- Changshu No.1 People's Hospital Affiliated to Soochow University, Department of General Surgery, Changshu, China
| | - Ming Li
- Changshu No.1 People's Hospital Affiliated to Soochow University, Department of General Surgery, Changshu, China
| | - Yinjie Xu
- Changshu No.1 People's Hospital Affiliated to Soochow University, Department of General Surgery, Changshu, China
| | - Chenxing Ge
- Changshu No.1 People's Hospital Affiliated to Soochow University, Department of General Surgery, Changshu, China
| | - Jianfeng Gu
- Changshu No.1 People's Hospital Affiliated to Soochow University, Department of General Surgery, Changshu, China
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5
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Zhao X, Qi Y, Wu T, Cheng G. Phosphoproteomic Analysis of the Jejunum Tissue Response to Colostrum and Milk Feeding in Dairy Calves during the Passive Immunity Period. Animals (Basel) 2022; 13:ani13010145. [PMID: 36611753 PMCID: PMC9817995 DOI: 10.3390/ani13010145] [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: 11/26/2022] [Revised: 12/21/2022] [Accepted: 12/28/2022] [Indexed: 12/31/2022] Open
Abstract
Improvements in the feeding of calves are of increasing importance for the development of the dairy industry. While colostrum is essential for the health of newborn calves, knowledge of protein phosphorylation alterations in neonatal calves that are fed colostrum or mature milk is lacking. Here, mid-jejunum tissue samples were collected from calves that received colostrum or milk. Subsequently, the jejunum phosphoproteome was analyzed using a phosphopeptide enrichment method, i.e., titanium immobilized metal ion affinity chromatography, coupled with liquid chromatography-tandem mass spectrometry. A total of 2093 phosphopeptides carrying unique 1851 phosphorylation sites corresponding to 1180 phosphoproteins were identified. Of the 1180 phosphoproteins, 314 phosphorylation sites on 241 proteins were differentially expressed between the groups. Gene ontology analysis indicated that the phosphoproteins were strongly associated with developmental and macromolecule metabolic processes, signal transduction, and responses to stimuli and insulin. Pathway analysis showed that the spliceosome, Hippo, insulin, and neurotrophin signaling pathways were enriched. These results reveal the expression pattern and changes in the function of phosphoproteins in bovine jejunum tissues under different feeding conditions and provide further insights into the crucial role of colostrum feeding during the early stages of life.
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Affiliation(s)
- Xiaowei Zhao
- Correspondence: ; Tel.: +86-551-65146065; Fax: +86-551-62160275
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6
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Yang Y, Liu JJ. Structural LTP: Signal transduction, actin cytoskeleton reorganization, and membrane remodeling of dendritic spines. Curr Opin Neurobiol 2022; 74:102534. [DOI: 10.1016/j.conb.2022.102534] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 02/14/2022] [Accepted: 03/03/2022] [Indexed: 01/05/2023]
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7
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Wang L, Bu T, Wu X, Gao S, Li X, De Jesus AB, Wong CKC, Chen H, Chung NPY, Sun F, Cheng CY. Cell-Cell Interaction-Mediated Signaling in the Testis Induces Reproductive Dysfunction—Lesson from the Toxicant/Pharmaceutical Models. Cells 2022; 11:cells11040591. [PMID: 35203242 PMCID: PMC8869896 DOI: 10.3390/cells11040591] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/18/2022] [Accepted: 01/26/2022] [Indexed: 02/01/2023] Open
Abstract
Emerging evidence has shown that cell-cell interactions between testicular cells, in particular at the Sertoli cell-cell and Sertoli-germ cell interface, are crucial to support spermatogenesis. The unique ultrastructures that support cell-cell interactions in the testis are the basal ES (ectoplasmic specialization) and the apical ES. The basal ES is found between adjacent Sertoli cells near the basement membrane that also constitute the blood-testis barrier (BTB). The apical ES is restrictively expressed at the Sertoli-spermatid contact site in the apical (adluminal) compartment of the seminiferous epithelium. These ultrastructures are present in both rodent and human testes, but the majority of studies found in the literature were done in rodent testes. As such, our discussion herein, unless otherwise specified, is focused on studies in testes of adult rats. Studies have shown that the testicular cell-cell interactions crucial to support spermatogenesis are mediated through distinctive signaling proteins and pathways, most notably involving FAK, Akt1/2 and Cdc42 GTPase. Thus, manipulation of some of these signaling proteins, such as FAK, through the use of phosphomimetic mutants for overexpression in Sertoli cell epithelium in vitro or in the testis in vivo, making FAK either constitutively active or inactive, we can modify the outcome of spermatogenesis. For instance, using the toxicant-induced Sertoli cell or testis injury in rats as study models, we can either block or rescue toxicant-induced infertility through overexpression of p-FAK-Y397 or p-FAK-Y407 (and their mutants), including the use of specific activator(s) of the involved signaling proteins against pAkt1/2. These findings thus illustrate that a potential therapeutic approach can be developed to manage toxicant-induced male reproductive dysfunction. In this review, we critically evaluate these recent findings, highlighting the direction for future investigations by bringing the laboratory-based research through a translation path to clinical investigations.
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Affiliation(s)
- Lingling Wang
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China; (L.W.); (T.B.); (X.W.); (S.G.)
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
| | - Tiao Bu
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China; (L.W.); (T.B.); (X.W.); (S.G.)
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
| | - Xiaolong Wu
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China; (L.W.); (T.B.); (X.W.); (S.G.)
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
| | - Sheng Gao
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China; (L.W.); (T.B.); (X.W.); (S.G.)
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
| | - Xinyao Li
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
| | | | - Chris K. C. Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong, China;
| | - Hao Chen
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
| | - Nancy P. Y. Chung
- Department of Genetic Medicine, Cornell Medical College, New York, NY 10065, USA;
| | - Fei Sun
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China; (L.W.); (T.B.); (X.W.); (S.G.)
- Correspondence: (F.S.); (C.Y.C.)
| | - C. Yan Cheng
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China; (L.W.); (T.B.); (X.W.); (S.G.)
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong 226001, China; (X.L.); (H.C.)
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA
- Correspondence: (F.S.); (C.Y.C.)
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Zhang WH, Koyuncu S, Vilchez D. Insights Into the Links Between Proteostasis and Aging From C. elegans. FRONTIERS IN AGING 2022; 3:854157. [PMID: 35821832 PMCID: PMC9261386 DOI: 10.3389/fragi.2022.854157] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/22/2022] [Indexed: 04/20/2023]
Abstract
Protein homeostasis (proteostasis) is maintained by a tightly regulated and interconnected network of biological pathways, preventing the accumulation and aggregation of damaged or misfolded proteins. Thus, the proteostasis network is essential to ensure organism longevity and health, while proteostasis failure contributes to the development of aging and age-related diseases that involve protein aggregation. The model organism Caenorhabditis elegans has proved invaluable for the study of proteostasis in the context of aging, longevity and disease, with a number of pivotal discoveries attributable to the use of this organism. In this review, we discuss prominent findings from C. elegans across the many key aspects of the proteostasis network, within the context of aging and disease. These studies collectively highlight numerous promising therapeutic targets, which may 1 day facilitate the development of interventions to delay aging and prevent age-associated diseases.
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Affiliation(s)
- William Hongyu Zhang
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Seda Koyuncu
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - David Vilchez
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Faculty of Medicine, University Hospital Cologne, Cologne, Germany
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9
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Liu L, Zhao J, Du X, Zhao Y, Zou C, Zhou H, Li W, Yan X. Construction and validation of a novel aging-related gene signature and prognostic nomogram for predicting the overall survival in ovarian cancer. Cancer Med 2021; 10:9097-9114. [PMID: 34825509 PMCID: PMC8683552 DOI: 10.1002/cam4.4404] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Ovarian cancer (OC) is the most lethal gynecological malignancy. The objective of this study was to establish and validate an individual aging-related gene signature and a clinical nomogram that can powerfully predict independently the overall survival rate of patients with ovarian cancer. METHODS Data on transcriptomic profile and relevant clinical information were retrieved from The Cancer Genome Atlas (TCGA) database as a training group, and the same data from three public Gene Expression Omnibus (GEO) databases as validation groups. Univariate Cox regression analysis, lasso regression analysis, and multiple multivariate Cox analysis were analyzed sequentially to select the genes to be included in the aging-associated signature. A risk scoring model was established and verified, the predictive value of the model was evaluated, and a clinical nomogram was established. RESULTS We found eight genes that were most relevant to prognosis and constructed an eight-mRNA signature. Based on the model, each OC patient's risk score was able to be calculated and patients were split into groups of low and high risks with a distinct outcome. Survival analysis confirmed that the outcome of patients in the high-risk group was dramatically shorter than that of those in the low-risk group, and the eight-mRNA signature can be considered as a powerful and independent predictor that could predict the outcome of OC patient. Additionally, the risk score and age can be used to construct a clinical nomogram as a simpler tool for predicting prognosis. We also explored the association between the risk score and immunity and drug sensitivity. CONCLUSION This study suggested that the aging-related gene signature could be used as an intervention point and latent prognostic predictor in OC, which may provide new perceptions for postoperative treatment strategies.
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Affiliation(s)
- Lixiao Liu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jinduo Zhao
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xuedan Du
- Department of Chemoradiation Oncology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Ye Zhao
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Chengyang Zou
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Heling Zhou
- Taizhou Hospital of Zhejiang Province affiliated to Wenzhou Medical University, Wenzhou, China
| | - Wenfeng Li
- Department of Chemoradiation Oncology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xiaojian Yan
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
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10
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Koyuncu S, Loureiro R, Lee HJ, Wagle P, Krueger M, Vilchez D. Rewiring of the ubiquitinated proteome determines ageing in C. elegans. Nature 2021; 596:285-290. [PMID: 34321666 PMCID: PMC8357631 DOI: 10.1038/s41586-021-03781-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 06/29/2021] [Indexed: 12/20/2022]
Abstract
Ageing is driven by a loss of cellular integrity1. Given the major role of ubiquitin modifications in cell function2, here we assess the link between ubiquitination and ageing by quantifying whole-proteome ubiquitin signatures in Caenorhabditis elegans. We find a remodelling of the ubiquitinated proteome during ageing, which is ameliorated by longevity paradigms such as dietary restriction and reduced insulin signalling. Notably, ageing causes a global loss of ubiquitination that is triggered by increased deubiquitinase activity. Because ubiquitination can tag proteins for recognition by the proteasome3, a fundamental question is whether deficits in targeted degradation influence longevity. By integrating data from worms with a defective proteasome, we identify proteasomal targets that accumulate with age owing to decreased ubiquitination and subsequent degradation. Lowering the levels of age-dysregulated proteasome targets prolongs longevity, whereas preventing their degradation shortens lifespan. Among the proteasomal targets, we find the IFB-2 intermediate filament4 and the EPS-8 modulator of RAC signalling5. While increased levels of IFB-2 promote the loss of intestinal integrity and bacterial colonization, upregulation of EPS-8 hyperactivates RAC in muscle and neurons, and leads to alterations in the actin cytoskeleton and protein kinase JNK. In summary, age-related changes in targeted degradation of structural and regulatory proteins across tissues determine longevity.
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Affiliation(s)
- Seda Koyuncu
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Rute Loureiro
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Hyun Ju Lee
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Prerana Wagle
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Marcus Krueger
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - David Vilchez
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
- Faculty of Medicine, University Hospital Cologne, Cologne, Germany.
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11
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Soriano O, Alcón-Pérez M, Vicente-Manzanares M, Castellano E. The Crossroads between RAS and RHO Signaling Pathways in Cellular Transformation, Motility and Contraction. Genes (Basel) 2021; 12:genes12060819. [PMID: 34071831 PMCID: PMC8229961 DOI: 10.3390/genes12060819] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 02/07/2023] Open
Abstract
Ras and Rho proteins are GTP-regulated molecular switches that control multiple signaling pathways in eukaryotic cells. Ras was among the first identified oncogenes, and it appears mutated in many forms of human cancer. It mainly promotes proliferation and survival through the MAPK pathway and the PI3K/AKT pathways, respectively. However, the myriad proteins close to the plasma membrane that activate or inhibit Ras make it a major regulator of many apparently unrelated pathways. On the other hand, Rho is weakly oncogenic by itself, but it critically regulates microfilament dynamics; that is, actin polymerization, disassembly and contraction. Polymerization is driven mainly by the Arp2/3 complex and formins, whereas contraction depends on myosin mini-filament assembly and activity. These two pathways intersect at numerous points: from Ras-dependent triggering of Rho activators, some of which act through PI3K, to mechanical feedback driven by actomyosin action. Here, we describe the main points of connection between the Ras and Rho pathways as they coordinately drive oncogenic transformation. We emphasize the biochemical crosstalk that drives actomyosin contraction driven by Ras in a Rho-dependent manner. We also describe possible routes of mechanical feedback through which myosin II activation may control Ras/Rho activation.
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Affiliation(s)
- Olga Soriano
- Tumor Biophysics Laboratory, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain;
| | - Marta Alcón-Pérez
- Tumour-Stroma Signalling Laboratory, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain;
| | - Miguel Vicente-Manzanares
- Tumor Biophysics Laboratory, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain;
- Correspondence: (M.V.-M.); (E.C.)
| | - Esther Castellano
- Tumour-Stroma Signalling Laboratory, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain;
- Correspondence: (M.V.-M.); (E.C.)
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12
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Luo K, Zhang L, Liao Y, Zhou H, Yang H, Luo M, Qing C. Effects and mechanisms of Eps8 on the biological behaviour of malignant tumours (Review). Oncol Rep 2021; 45:824-834. [PMID: 33432368 PMCID: PMC7859916 DOI: 10.3892/or.2021.7927] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 12/09/2020] [Indexed: 12/31/2022] Open
Abstract
Epidermal growth factor receptor pathway substrate 8 (Eps8) was initially identified as the substrate for the kinase activity of EGFR, improving the responsiveness of EGF, which is involved in cell mitosis, differentiation and other physiological functions. Numerous studies over the last decade have demonstrated that Eps8 is overexpressed in most ubiquitous malignant tumours and subsequently binds with its receptor to activate multiple signalling pathways. Eps8 not only participates in the regulation of malignant phenotypes, such as tumour proliferation, invasion, metastasis and drug resistance, but is also related to the clinicopathological characteristics and prognosis of patients. Therefore, Eps8 is a potential tumour diagnosis and prognostic biomarker and even a therapeutic target. This review aimed to describe the structural characteristics, role and related molecular mechanism of Eps8 in malignant tumours. In addition, the prospect of Eps8 as a target for cancer therapy is examined.
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Affiliation(s)
- Kaili Luo
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Lei Zhang
- Department of Gynecology, Yunnan Tumor Hospital and The Third Affiliated Hospital of Kunming Medical University; Kunming, Yunnan 650118, P.R. China
| | - Yuan Liao
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Hongyu Zhou
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Hongying Yang
- Department of Gynecology, Yunnan Tumor Hospital and The Third Affiliated Hospital of Kunming Medical University; Kunming, Yunnan 650118, P.R. China
| | - Min Luo
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Chen Qing
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
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Liu SW, Li HT, Ge RS, Cheng CY. NC1-peptide derived from collagen α3 (IV) chain is a blood-tissue barrier regulator: lesson from the testis. Asian J Androl 2021; 23:123-128. [PMID: 32896837 PMCID: PMC7991810 DOI: 10.4103/aja.aja_44_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Collagen α3 (IV) chains are one of the major constituent components of the basement membrane in the mammalian testis. Studies have shown that biologically active fragments, such as noncollagenase domain (NC1)-peptide, can be released from the C-terminal region of collagen α3 (IV) chains, possibly through the proteolytic action of metalloproteinase 9 (MMP9). NC1-peptide was shown to promote blood–testis barrier (BTB) remodeling and fully developed spermatid (e.g., sperm) release from the seminiferous epithelium because this bioactive peptide was capable of perturbing the organization of both actin- and microtubule (MT)-based cytoskeletons at the Sertoli cell–cell and also Sertoli–spermatid interface, the ultrastructure known as the basal ectoplasmic specialization (ES) and apical ES, respectively. More importantly, recent studies have shown that this NC1-peptide-induced effects on cytoskeletal organization in the testis are mediated through an activation of mammalian target of rapamycin complex 1/ribosomal protein S6/transforming retrovirus Akt1/2 protein (mTORC1/rpS6/Akt1/2) signaling cascade, involving an activation of cell division control protein 42 homolog (Cdc42) GTPase, but not Ras homolog family member A GTPase (RhoA), and the participation of end-binding protein 1 (EB1), a microtubule plus (+) end tracking protein (+TIP), downstream. Herein, we critically evaluate these findings, providing a critical discussion by which the basement membrane modulates spermatogenesis through one of its locally generated regulatory peptides in the testis.
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Affiliation(s)
- Shi-Wen Liu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou 325027, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, USA
| | - Hui-Tao Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou 325027, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, USA
| | - Ren-Shan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou 325027, China
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou 325027, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, USA
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14
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Baltanás FC, Zarich N, Rojas-Cabañeros JM, Santos E. SOS GEFs in health and disease. Biochim Biophys Acta Rev Cancer 2020; 1874:188445. [PMID: 33035641 DOI: 10.1016/j.bbcan.2020.188445] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 12/11/2022]
Abstract
SOS1 and SOS2 are the most universal and widely expressed family of guanine exchange factors (GEFs) capable or activating RAS or RAC1 proteins in metazoan cells. SOS proteins contain a sequence of modular domains that are responsible for different intramolecular and intermolecular interactions modulating mechanisms of self-inhibition, allosteric activation and intracellular homeostasis. Despite their homology, analyses of SOS1/2-KO mice demonstrate functional prevalence of SOS1 over SOS2 in cellular processes including proliferation, migration, inflammation or maintenance of intracellular redox homeostasis, although some functional redundancy cannot be excluded, particularly at the organismal level. Specific SOS1 gain-of-function mutations have been identified in inherited RASopathies and various sporadic human cancers. SOS1 depletion reduces tumorigenesis mediated by RAS or RAC1 in mouse models and is associated with increased intracellular oxidative stress and mitochondrial dysfunction. Since WT RAS is essential for development of RAS-mutant tumors, the SOS GEFs may be considered as relevant biomarkers or therapy targets in RAS-dependent cancers. Inhibitors blocking SOS expression, intrinsic GEF activity, or productive SOS protein-protein interactions with cellular regulators and/or RAS/RAC targets have been recently developed and shown preclinical and clinical effectiveness blocking aberrant RAS signaling in RAS-driven and RTK-driven tumors.
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Affiliation(s)
- Fernando C Baltanás
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Natasha Zarich
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Jose M Rojas-Cabañeros
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Eugenio Santos
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain.
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15
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Yang T, Yang WX. The dynamics and regulation of microfilament during spermatogenesis. Gene 2020; 744:144635. [PMID: 32244053 DOI: 10.1016/j.gene.2020.144635] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/28/2020] [Accepted: 03/30/2020] [Indexed: 12/22/2022]
Abstract
Spermatogenesis is a highly complex physiological process which contains spermatogonia proliferation, spermatocyte meiosis and spermatid morphogenesis. In the past decade, actin binding proteins and signaling pathways which are critical for regulating the actin cytoskeleton in testis had been found. In this review, we summarized 5 actin-binding proteins that have been proven to play important roles in the seminiferous epithelium. Lack of them perturbs spermatids polarity and the transport of spermatids. The loss of Arp2/3 complex, Formin1, Eps8, Palladin and Plastin3 cause sperm release failure suggesting their irreplaceable role in spermatogenesis. Actin regulation relies on multiple signal pathways. The PI3K/Akt signaling pathway positively regulate the mTOR pathway to promote actin reorganization in seminiferous epithelium. Conversely, TSC1/TSC2 complex, the upstream of mTOR, is activated by the LKB1/AMPK pathway to inhibit cell proliferation, differentiation and migration. The increasing researches focus on the function of actin binding proteins (ABPs), however, their collaborative regulation of actin patterns and potential regulatory signaling networks remains unclear. We reviewed ABPs that play important roles in mammalian spermatogenesis and signal pathways involved in the regulation of microfilaments. We suggest that more relevant studies should be performed in the future.
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Affiliation(s)
- Tong Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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16
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Yang G, Lu YB, Guan QL. EPS8 is a Potential Oncogene in Glioblastoma. Onco Targets Ther 2019; 12:10523-10534. [PMID: 31819533 PMCID: PMC6898995 DOI: 10.2147/ott.s227739] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 11/15/2019] [Indexed: 12/30/2022] Open
Abstract
Purpose In this study, we investigated the expression and function of Epidermal growth factor receptor kinase substrate 8 (EPS8) in glioblastoma (GBM), and further explored the underlying mechanisms that regulate it. Patients and methods The expression and potential mechanisms of EPS8 in GBM were evaluated through multiple online public databases. The expression level EPS8 in GBM tissues and cell lines were detected by immunohistochemical staining and Western blot. Then, the prognosis of EPS8 and GBM patients were analyzed. Loss-of-function experiments were conducted to determine the role of EPS8 for the biological behavior of GBM cells. In addition, the tumorigenic ability of nude mice was tested in vivo. Results EPS8 is highly expressed in GBM tissues and indicates poor patient prognosis. In cell experiments, EPS8 can promote the proliferation, migration and invasion of GBM cells. In vivo, EPS8 promotes tumor formation in nude mice. EPS8 can activate the PI3K/Akt signaling pathway to function. Conclusion EP8S plays a role in the development of GBM and may be a potential therapeutic target for GBM.
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Affiliation(s)
- Gang Yang
- Department of Neurosurgery, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, People's Republic of China.,The First Clinical Medical College of Lanzhou University, Lanzhou, Gansu 730000, People's Republic of China
| | - Yong-Bin Lu
- Department of Technology, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, People's Republic of China
| | - Quan-Lin Guan
- The First Clinical Medical College of Lanzhou University, Lanzhou, Gansu 730000, People's Republic of China.,Department of Oncology Surgery, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, People's Republic of China
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17
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Larson GP, Tran V, Yú S, Caì Y, Higgins CA, Smith DM, Baker SF, Radoshitzky SR, Kuhn JH, Mehle A. EPS8 Facilitates Uncoating of Influenza A Virus. Cell Rep 2019; 29:2175-2183.e4. [PMID: 31747592 PMCID: PMC6929677 DOI: 10.1016/j.celrep.2019.10.064] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 08/20/2019] [Accepted: 10/15/2019] [Indexed: 12/02/2022] Open
Abstract
All viruses balance interactions between cellular machinery co-opted to support replication and host factors deployed to halt the infection. We use gene correlation analysis to perform an unbiased screen for host factors involved in influenza A virus (FLUAV) infection. Our screen identifies the cellular factor epidermal growth factor receptor pathway substrate 8 (EPS8) as the highest confidence pro-viral candidate. Knockout and overexpression of EPS8 confirm its importance in enhancing FLUAV infection and titers. Loss of EPS8 does not affect virion attachment, uptake, or fusion. Rather, our data show that EPS8 specifically functions during virion uncoating. EPS8 physically associates with incoming virion components, and subsequent nuclear import of released ribonucleoprotein complexes is significantly delayed in the absence of EPS8. Our study identifies EPS8 as a host factor important for uncoating, a crucial step of FLUAV infection during which the interface between the virus and host is still being discovered.
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Affiliation(s)
- Gloria P Larson
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Vy Tran
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Shuǐqìng Yú
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702, USA
| | - Yíngyún Caì
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702, USA
| | - Christina A Higgins
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Danielle M Smith
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Steven F Baker
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sheli R Radoshitzky
- Molecular and Translational Sciences Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, MD 21702, USA
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702, USA
| | - Andrew Mehle
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA.
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18
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Wu S, Yan M, Li L, Mao B, Wong CKC, Ge R, Lian Q, Cheng CY. mTORC1/rpS6 and spermatogenic function in the testis-insights from the adjudin model. Reprod Toxicol 2019; 89:54-66. [PMID: 31278979 PMCID: PMC6825331 DOI: 10.1016/j.reprotox.2019.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/12/2019] [Accepted: 07/02/2019] [Indexed: 12/13/2022]
Abstract
mTORC1/rpS6 signaling complex promoted Sertoli blood-testis barrier (BTB) remodeling by perturbing Sertoli cell-cell adhesion site known as the basal ectoplasmic specialization (ES). mTORC1/rpS6 complex also promoted disruption of spermatid adhesion at the Sertoli-spermatid interface called the apical ES. Herein, we performed analyses using the adjudin (a non-hormonal male contraceptive drug under development) model, wherein adjudin was known to perturb apical and basal ES function when used at high dose. Through direct administration of adjudin to the testis, adjudin at doses that failed to perturb BTB integrity per se, overexpression of an rpS6 phosphomimetic (i.e., constitutively active) mutant (i.e., p-rpS6-MT) that modified BTB function considerably potentiated adjudin efficacy. This led to disorderly spatial expression of proteins necessary to maintain the proper cytoskeletal organization of F-actin and microtubules (MTs) across the seminiferous epithelium, leading to germ cell exfoliation and aspermatogenesis. These findings yielded important insights regarding the role of mTORC1/rpS6 signaling complex in regulating BTB homeostasis.
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Affiliation(s)
- Siwen Wu
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States
| | - Ming Yan
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, Nanjing, China
| | - Linxi Li
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States
| | - Baiping Mao
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong, China
| | - Renshan Ge
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Qingquan Lian
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - C Yan Cheng
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States.
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19
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Yu X, Liang C, Zhang Y, Zhang W, Chen H. Inhibitory short peptides targeting EPS8/ABI1/SOS1 tri-complex suppress invasion and metastasis of ovarian cancer cells. BMC Cancer 2019; 19:878. [PMID: 31488087 PMCID: PMC6727365 DOI: 10.1186/s12885-019-6087-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 08/23/2019] [Indexed: 01/13/2023] Open
Abstract
Background We aimed to develop inhibitory short peptides that can prevent protein interactions of SOS1/EPS8/ABI1 tri-complex, a key component essential for ovarian cancer metastasis. Methods Plasmids containing various regions of HA-tagged ABI1 were co-transfected into ovarian cancer cells with Flag-tagged SOS1 or Myc-tagged EPS8. Co-immunoprecipitation and GST-pulldown assay were used to identify the regions of ABI1 responsible for SOS1 and EPS8 binding. Inhibitory short peptides of these binding regions were synthesized and modified with HIV-TAT sequence. The blocking effects of the peptides on ABI1-SOS1 or ABI1-EPS8 interactions in vitro and in vivo were determined by GST-pulldown assay. The capability of these short peptides in inhibiting invasion and metastasis of ovarian cancer cell was tested by Matrigel invasion assay and peritoneal metastatic colonization assay. Results The formation of endogenous SOS1/EPS8/ABI1 tri-complex was detected in the event of LPA-induced ovarian cancer cell invasion. In the tri-complex, ABI1 acted as a scaffold protein holding together SOS1 and EPS8. The SH3 and poly-proline+PxxDY regions of ABI1 were responsible for SOS1 and EPS8 binding, respectively. Inhibitory short peptides p + p-8 (ppppppppvdyedee) and SH3–3 (ekvvaiydytkdkddelsfmegaii) could block ABI1-SOS1 and ABI1-EPS8 interaction in vitro. TAT-p + p-8 peptide could disrupt ABI1-EPS8 interaction and suppress the invasion and metastasis of ovarian cancer cells in vivo. Conclusions TAT-p + p-8 peptide could efficiently disrupt the ABI1-EPS8 interaction, tri-complex formation, and block the invasion and metastasis of ovarian cancer cells.
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Affiliation(s)
- Xuechen Yu
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei, China
| | - Chuan Liang
- Department of Cardiothoracic vascular surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei, China
| | - Yuanzhen Zhang
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei, China
| | - Wei Zhang
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei, China
| | - Huijun Chen
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei, China.
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Mao BP, Li L, Ge R, Li C, Wong CKC, Silvestrini B, Lian Q, Cheng CY. CAMSAP2 Is a Microtubule Minus-End Targeting Protein That Regulates BTB Dynamics Through Cytoskeletal Organization. Endocrinology 2019; 160:1448-1467. [PMID: 30994903 PMCID: PMC6530524 DOI: 10.1210/en.2018-01097] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 04/11/2019] [Indexed: 01/26/2023]
Abstract
During spermatogenesis, microtubule (MT) cytoskeleton in Sertoli cells confers blood-testis barrier (BTB) function, but the regulators and mechanisms that modulate MT dynamics remain unexplored. In this study, we examined the role of calmodulin-regulated spectrin-associated protein (CAMSAP)2 (a member of the CAMSAP/Patronin protein family), and a minus-end targeting protein (-TIP) that binds to the minus-end (i.e., slow-growing end) of polarized MTs involved in determining MT length, in Sertoli cell function. CAMSAP2 was found to localize at discrete sites across the Sertoli cell cytosol, different from end-binding protein 1 (a microtubule plus-end tracking protein that binds to the plus-end of MTs), and colocalized with MTs. CAMSAP2 displayed a stage-specific expression pattern, appearing as tracklike structures across the seminiferous epithelium in adult rat testes that lay perpendicular to the basement membrane. CAMSAP2 knockdown by RNA interference was found to promote Sertoli cell tight junction (TJ) barrier function, illustrating its role in inducing TJ remodeling under physiological conditions. To further examine the regulatory role of CAMSAP2 in BTB dynamics, we used a perfluorooctanesulfonate (PFOS)-induced Sertoli cell injury model for investigations. CAMSAP2 knockdown blocked PFOS-induced Sertoli cell injury by promoting proper distribution of BTB-associated proteins at the cell-cell interface. This effect was mediated by the ability of CAMSAP2 knockdown to block PFOS-induced disruptive organization of MTs, but also F-actin, across cell cytosol through changes in cellular distribution/localization of MT- and actin-regulatory proteins. In summary, CAMSAP2 is a regulator of MT and actin dynamics in Sertoli cells to support BTB dynamics and spermatogenesis.
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Affiliation(s)
- Bai-ping Mao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Zhejiang, China
| | - Linxi Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Zhejiang, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Zhejiang, China
| | - Chao Li
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Zhejiang, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong, China
| | | | - Qingquan Lian
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Zhejiang, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York
- Correspondence: C. Yan Cheng, PhD, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065. E-mail:
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Li M, Yang J, Zhang L, Tu S, Zhou X, Tan Z, Zhou W, He Y, Li Y. A low-molecular-weight compound exerts anticancer activity against breast and lung cancers by disrupting EGFR/Eps8 complex formation. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2019; 38:211. [PMID: 31118055 PMCID: PMC6532146 DOI: 10.1186/s13046-019-1207-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 05/02/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Epidermal growth factor receptor (EGFR) and epidermal growth factor receptor pathway substrate 8 (Eps8) have been widely reported to be expressed in various tumors. Eps8 is an important active kinase substrate of EGFR that directly binds to the juxtamembrane (JXM) domain of EGFR to form an EGFR/Eps8 complex. The EGFR/Eps8 complex is involved in regulating cancer progression and might be an ideal target for antitumor therapy. This study focused on the screening of small-molecule inhibitors that target the EGFR/Eps8 complex in breast cancer and non-small cell lung cancer (NSCLC). METHODS In silico virtual screening was used to identify small-molecule EGFR/Eps8 complex inhibitors. These compounds were screened for the inhibition of A549 and BT549 cell viability. The direct interaction between EGFR and Eps8 was measured using coimmunoprecipitation (CoIP) and JXM domain replacement assays. The antitumor effects of the inhibitors were analyzed in cancer cells and xenograft models. An acute toxicity study of EE02 was performed in a mouse model. In addition, the effect of the EE02 inhibitor on the protein expression of elements downstream of the EGFR/Eps8 complex was determined by western blotting and protein chip assays. RESULTS In this study of nearly 390,000 compounds screened by virtual database screening, the top 29 compounds were identified as candidate small-molecule EGFR/Eps8 complex inhibitors and evaluated by using cell-based assays. The compound EE02 was identified as the best match to our selection criteria. Further investigation demonstrated that EE02 directly bound to the JXM domain of EGFR and disrupted EGFR/Eps8 complex formation. EE02 selectively suppressed growth and induced apoptosis in EGFR-positive and Eps8-positive breast cancer and NSCLC cells. More importantly, the PI3K/Akt/mTOR and MAPK/Erk pathways downstream of the EGFR/Eps8 complex were suppressed by EE02. In addition, the suppressive effect of EE02 on tumor growth in vivo was comparable to that of erlotinib at the same dose. CONCLUSIONS We identified EE02 as an EGFR/Eps8 complex inhibitor that demonstrated promising antitumor effects in breast cancer and NSCLC. Our data suggest that the EGFR/Eps8 complex offers a novel cancer drug target.
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Affiliation(s)
- Meifang Li
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China
| | - Jilong Yang
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China
| | - Lenghe Zhang
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China
| | - Sanfang Tu
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China
| | - Xuan Zhou
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China
| | - Ze Tan
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, People's Republic of China
| | - Weijun Zhou
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China.
| | - Yanjie He
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China.
| | - Yuhua Li
- Department of Hematology, Zhujiang Hospital, Southern Medical University, No. 253 GongyeDadaoZhong, Guangzhou, Guangdong, 510282, People's Republic of China.
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Ngan AWL, Grace Tsui M, So DHF, Leung WY, Chan DW, Yao KM. Novel Nuclear Partnering Role of EPS8 With FOXM1 in Regulating Cell Proliferation. Front Oncol 2019; 9:154. [PMID: 30941306 PMCID: PMC6433973 DOI: 10.3389/fonc.2019.00154] [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: 08/13/2018] [Accepted: 02/22/2019] [Indexed: 01/07/2023] Open
Abstract
One hallmark of cancer cells is sustaining proliferative signaling that leads to uncontrolled cell proliferation. Both the Forkhead box (FOX) M1 transcription factor and the Epidermal Growth Factor (EGF) receptor Pathway Substrate 8 (EPS8) are known to be activated by mitogenic signaling and their levels upregulated in cancer. Well-known to regulate Rac-mediated actin remodeling at the cell cortex, EPS8 carries a nuclear localization signal but its possible nuclear role remains unclear. Here, we demonstrated interaction of FOXM1 with EPS8 in yeast two-hybrid and immunoprecipitation assays. Immunostaining revealed co-localization of the two proteins during G2/M phase of the cell cycle. EPS8 became nuclear localized when CRM1/Exportin 1-dependent nuclear export was inhibited by Leptomycin B, and a functional nuclear export signal could be identified within EPS8 using EGFP-tagging and site-directed mutagenesis. Downregulation of EPS8 using shRNAs suppressed expression of FOXM1 and the FOXM1-target CCNB1, and slowed down G2/M transition in cervical cancer cells. Chromatin immunoprecipitation analysis indicated recruitment of EPS8 to the CCNB1 and CDC25B promoters. Taken together, our findings support a novel partnering role of EPS8 with FOXM1 in the regulation of cancer cell proliferation and provides interesting insight into future design of therapeutic strategy to inhibit cancer cell proliferation.
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Affiliation(s)
- Adaline Wan Ling Ngan
- School of Biomedical Sciences, The LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Michelle Grace Tsui
- School of Biomedical Sciences, The LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Danny Hon Fai So
- School of Biomedical Sciences, The LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Wai Ying Leung
- School of Biomedical Sciences, The LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - David W Chan
- Department of Obstetrics and Gynaecology, The LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Kwok-Ming Yao
- School of Biomedical Sciences, The LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
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Planar cell polarity protein Dishevelled 3 (Dvl3) regulates ectoplasmic specialization (ES) dynamics in the testis through changes in cytoskeletal organization. Cell Death Dis 2019; 10:194. [PMID: 30808893 PMCID: PMC6391420 DOI: 10.1038/s41419-019-1394-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 11/22/2018] [Accepted: 01/24/2019] [Indexed: 01/31/2023]
Abstract
In the mammalian testes, such as in rats, the directional alignment of polarized elongating/elongated spermatids, in particular step 17–19 spermatids, across the plane of seminiferous epithelium resembles planar cell polarity (PCP) found in hair cells of the cochlea. It is obvious that spermatid PCP is necessary to support the simultaneous development of maximal number of elongating/elongated spermatids to sustain the daily production of > 50 million sperm per adult rat. Studies have shown that the testis indeed expresses multiple PCP proteins necessary to support spermatid PCP. Herein, using physiological and biochemical assays, and morphological analysis, and with the technique of RNA interference (RNAi) to knockdown PCP protein Dishevelled (Dvl) 1 (Dvl1), Dvl2, Dvl3, or Dvl1/2/3, Dvl proteins, in particular Dvl3, it was shown that Dvl3 played a crucial role of support Sertoli cell tight junction (TJ)-permeability barrier function through changes in the organization of actin- and microtubule (MT)-based cytoskeletons. More important, an in vivo knockdown of Dvl1/2/3 in the testis, defects of spermatid polarity were remarkably noted across the seminiferous epithelium, concomitant with defects of spermatid adhesion and spermatid transport, leading to considerably defects in spermatogenesis. More important, Dvl1/2/3 triple knockdown in the testis also impeded the organization of actin- and MT-based cytoskeletons owing to disruptive spatial expression of actin- and MT-regulatory proteins. In summary, PCP Dishevelled proteins, in particular, Dvl3 is a regulator of Sertoli cell blood–testis barrier (BTB) and also spermatid PCP function through its effects on the actin- and MT-based cytoskeletons in Sertoli cells.
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A synthetic cell-penetrating peptide derived from nuclear localization signal of EPS8 exerts anticancer activity against acute myeloid leukemia. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2018; 37:12. [PMID: 29357910 PMCID: PMC5778704 DOI: 10.1186/s13046-018-0682-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/16/2018] [Indexed: 02/07/2023]
Abstract
Background Oncogenic roles of epidermal growth factor receptor pathway substrate no.8 (EPS8) have been widely reported in various tumors, making targeting of EPS8 an appealing prospect. Here, we describe the role of EPS8 in acute myeloid leukemia (AML) and consider the potential of EPS8 as an anti-AML target. Nuclear localization signal (NLS) residues of tumor-associated proteins are crucial for cell cycle progression, and specific inhibitors derived from the NLS have inhibitory effect on cancer cells. The NLS in EPS8 has potential as a specific anti-AML target. Methods Gene Expression Omnibus expression profiles of AML patients were used to test associations between EPS8 expression and AML patient outcome. The biological characteristics of AML cells after EPS8 knockdown were analyzed in vitro and in vivo. A specific peptide (CP-EPS8-NLS) derived from the NLS of EPS8 (amino acids 298–310) was synthesized, and the anti-AML effects of CP-EPS8-NLS were analyzed in cancer cells and in xenograft models. Mutated CP-EPS8-NLS and penetratin served as controls. Results We observed that elevated EPS8 expression in AML patients is associated with poor outcome. Knockdown of EPS8 significantly suppressed the survival of AML cells in vitro and in vivo. CP-EPS8-NLS interfered with EPS8-associated signaling and consequently exerted anti-AML activity. Importantly, CP-EPS8-NLS displayed anti-AML activity in various AML cell types, with diminished activity in PBMCs. CP-ESP8-NLS suppressed U937 cell proliferation, and injection of CP-EPS8-NLS exerted potent antitumor activity in the xenograft tumor models. A synergistic effect of CP-EPS8-NLS and chemotherapeutic agents was also observed in vitro and in vivo. Mechanistically, treatment of various AML cells with CP-EPS8-NLS downregulated the expression of EPS8 and its downstream pathways. Conclusions The function of CP-EPS8-NLS is explained by the presence of a NLS in EPS8, which has been shown to induce nuclear translocation, consequently resulting in EPS8 overexpression. These results indicate that EPS8 is a potential target for AML treatment. Electronic supplementary material The online version of this article (10.1186/s13046-018-0682-x) contains supplementary material, which is available to authorized users.
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Buro C, Burmeister C, Quack T, Grevelding CG. Identification and first characterization of SmEps8, a potential interaction partner of SmTK3 and SER transcribed in the gonads of Schistosoma mansoni. Exp Parasitol 2016; 180:55-63. [PMID: 28017636 DOI: 10.1016/j.exppara.2016.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 10/28/2016] [Accepted: 12/05/2016] [Indexed: 02/07/2023]
Abstract
In eukaryotes the roles of protein kinases (PKs) regulating important biological processes such as growth and differentiation are well known. Molecular, biochemical, and physiological analyses trying to unravel principles of schistosome development have substantiated the importance for PKs also in this parasite. Amongst others the role of SmTK3 was studied, one of the first cellular PKs characterized from Schistosoma mansoni. Its function was demonstrated in mitogenic and differentiation processes in the gonads. Furthermore, first insights were obtained for the downstream part of a signal transduction cascade SmTK3 is involved in, which includes the diaphanous homolog SmDia. Here we attempted to further unravel the SmTK3 signaling cascade by searching for upstream interaction partners. Using yeast three-hybrid (Y3H) analyses we detected the epidermal growth factor receptor (EGFR) pathway substrate 8 of S. mansoni (SmEps8) as the most interesting candidate. By detailed interaction analyses we showed a contribution of the Src homology (SH) domains SH2 and SH3 of SmTK3 to binding, with a clear bias towards SH2. Compared to full-length SmEps8, binding was enhanced when only its 5' part including the phosphotyrosine binding domain (PTB) was used for interaction analyses including the SH2 domain of SmTK3, although phosphorylation seemed not to play a decisive role for binding. RT-PCR analyses and in situ hybridization experiments demonstrated similar transcription patterns of SmTK3 and SmEPS8, which co-localize in the reproductive organs. Furthermore, first evidence was obtained for SmEps8 interaction and colocalization with SER, one of the epidermal growth factor receptor (EGFR) homologs detected in S. mansoni. The results of this study provide first evidence for a SER-SmEps8-SmTK3-SmDia signal transduction pathway controlling differentiation processes in the gonads of S. mansoni.
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Affiliation(s)
- C Buro
- BFS, Institute of Parasitology, Justus-Liebig-University Giessen, Germany
| | - C Burmeister
- BFS, Institute of Parasitology, Justus-Liebig-University Giessen, Germany
| | - T Quack
- BFS, Institute of Parasitology, Justus-Liebig-University Giessen, Germany
| | - C G Grevelding
- BFS, Institute of Parasitology, Justus-Liebig-University Giessen, Germany.
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Delage E, Cervantes DC, Pénard E, Schmitt C, Syan S, Disanza A, Scita G, Zurzolo C. Differential identity of Filopodia and Tunneling Nanotubes revealed by the opposite functions of actin regulatory complexes. Sci Rep 2016; 6:39632. [PMID: 28008977 PMCID: PMC5180355 DOI: 10.1038/srep39632] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 11/25/2016] [Indexed: 11/09/2022] Open
Abstract
Tunneling Nanotubes (TNTs) are actin enriched filopodia-like protrusions that play a pivotal role in long-range intercellular communication. Different pathogens use TNT-like structures as "freeways" to propagate across cells. TNTs are also implicated in cancer and neurodegenerative diseases, making them promising therapeutic targets. Understanding the mechanism of their formation, and their relation with filopodia is of fundamental importance to uncover their physiological function, particularly since filopodia, differently from TNTs, are not able to mediate transfer of cargo between distant cells. Here we studied different regulatory complexes of actin, which play a role in the formation of both these structures. We demonstrate that the filopodia-promoting CDC42/IRSp53/VASP network negatively regulates TNT formation and impairs TNT-mediated intercellular vesicle transfer. Conversely, elevation of Eps8, an actin regulatory protein that inhibits the extension of filopodia in neurons, increases TNT formation. Notably, Eps8-mediated TNT induction requires Eps8 bundling but not its capping activity. Thus, despite their structural similarities, filopodia and TNTs form through distinct molecular mechanisms. Our results further suggest that a switch in the molecular composition in common actin regulatory complexes is critical in driving the formation of either type of membrane protrusion.
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Affiliation(s)
- Elise Delage
- Unité Trafic Membranaire et Pathogenèse, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris CEDEX 15, France
| | - Diégo Cordero Cervantes
- Unité Trafic Membranaire et Pathogenèse, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris CEDEX 15, France
| | - Esthel Pénard
- Unité Trafic Membranaire et Pathogenèse, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris CEDEX 15, France
| | - Christine Schmitt
- Ultrapole, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris CEDEX 15, France
| | - Sylvie Syan
- Unité Trafic Membranaire et Pathogenèse, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris CEDEX 15, France
| | - Andrea Disanza
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Giorgio Scita
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy.,Dipartimento di Scienze della Salute, Università degli Studi di Milano, 20122 Milan, Italy
| | - Chiara Zurzolo
- Unité Trafic Membranaire et Pathogenèse, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris CEDEX 15, France
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Wang YT, Huang CC, Lin YS, Huang WF, Yang CY, Lee CC, Yeh CM, Hsu KS. Conditional deletion of Eps8 reduces hippocampal synaptic plasticity and impairs cognitive function. Neuropharmacology 2016; 112:113-123. [PMID: 27450093 DOI: 10.1016/j.neuropharm.2016.07.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/28/2016] [Accepted: 07/18/2016] [Indexed: 10/21/2022]
Abstract
Epidermal growth factor receptor substrate 8 (Eps8) is a multifunctional protein involved in actin cytoskeleton regulation and is abundantly expressed in many brain regions. However, the functional significance of Eps8 in the brain has only just begun to be elucidated. Here, we demonstrate that genetic deletion of Eps8 (Eps8-/-) from excitatory neurons leads to impaired performance in a novel object recognition test. Consistently, Eps8-/- mice displayed a deficit in the maintenance of long-term potentiation in the CA1 region of hippocampal slices, which was rescued by bath application of N-methyl-d-aspartate receptor (NMDAR) antagonist 2-amino-5-phosphonopentanoate. While Eps8-/- mice showed normal basal synaptic transmission, a significant increase in the amplitude and a significantly slower decay kinetic of NMDAR-mediated excitatory postsynaptic currents (EPSCs) were observed in hippocampal CA1 neurons. Furthermore, a significant increase in the expression of ifenprodil-sensitive NMDAR-mediated EPSCs was observed in neurons from Eps8-/- mice compared with those from wild-type mice. Eps8 deletion led to decreased mature mushroom-shaped dendritic spine density but increased complexity of basal dendritic trees of hippocampal CA1 pyramidal neurons. These results implicate NMDAR hyperfunction in the cognitive deficits observed in Eps8-/- mice and demonstrate a novel role for Eps8 in regulating hippocampal long-term synaptic plasticity and cognitive function. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'.
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Affiliation(s)
- Yu-Ting Wang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Chiung-Chun Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Yun-Shan Lin
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Weu-Fang Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Cheng-Yi Yang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Cheng-Che Lee
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Che-Ming Yeh
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Kuei-Sen Hsu
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan; Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan.
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Tavazzani E, Spaiardi P, Zampini V, Contini D, Manca M, Russo G, Prigioni I, Marcotti W, Masetto S. Distinct roles of Eps8 in the maturation of cochlear and vestibular hair cells. Neuroscience 2016; 328:80-91. [PMID: 27132230 DOI: 10.1016/j.neuroscience.2016.04.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 04/12/2016] [Accepted: 04/24/2016] [Indexed: 11/17/2022]
Abstract
Several genetic mutations affecting the development and function of mammalian hair cells have been shown to cause deafness but not vestibular defects, most likely because vestibular deficits are sometimes centrally compensated. The study of hair cell physiology is thus a powerful direct approach to ascertain the functional status of the vestibular end organs. Deletion of Epidermal growth factor receptor pathway substrate 8 (Eps8), a gene involved in actin remodeling, has been shown to cause deafness in mice. While both inner and outer hair cells from Eps8 knockout (KO) mice showed abnormally short stereocilia, inner hair cells (IHCs) also failed to acquire mature-type ion channels. Despite the fact that Eps8 is also expressed in vestibular hair cells, Eps8 KO mice show no vestibular deficits. In the present study we have investigated the properties of vestibular Type I and Type II hair cells in Eps8-KO mice and compared them to those of cochlear IHCs. In the absence of Eps8, vestibular hair cells show normally long kinocilia, significantly shorter stereocilia and a normal pattern of basolateral voltage-dependent ion channels. We have also found that while vestibular hair cells from Eps8 KO mice show normal voltage responses to injected sinusoidal currents, which were used to mimic the mechanoelectrical transducer current, IHCs lose their ability to synchronize their responses to the stimulus. We conclude that the absence of Eps8 produces a weaker phenotype in vestibular hair cells compared to cochlear IHCs, since it affects the hair bundle morphology but not the basolateral membrane currents. This difference is likely to explain the absence of obvious vestibular dysfunction in Eps8 KO mice.
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Affiliation(s)
- Elisa Tavazzani
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Paolo Spaiardi
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Valeria Zampini
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy.
| | - Donatella Contini
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy.
| | - Marco Manca
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Giancarlo Russo
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Ivo Prigioni
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Walter Marcotti
- Department of Biomedical Science, Sensory Neuroscience Group, Alfred Denny Building (B1 221), University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
| | - Sergio Masetto
- Department of Brain and Behavioral Sciences, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy.
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Giampietro C, Disanza A, Bravi L, Barrios-Rodiles M, Corada M, Frittoli E, Savorani C, Lampugnani MG, Boggetti B, Niessen C, Wrana JL, Scita G, Dejana E. The actin-binding protein EPS8 binds VE-cadherin and modulates YAP localization and signaling. J Cell Biol 2015; 211:1177-92. [PMID: 26668327 PMCID: PMC4687874 DOI: 10.1083/jcb.201501089] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 11/10/2015] [Indexed: 12/13/2022] Open
Abstract
Vascular endothelial (VE)-cadherin transfers intracellular signals contributing to vascular hemostasis. Signaling through VE-cadherin requires association and activity of different intracellular partners. Yes-associated protein (YAP)/TAZ transcriptional cofactors are important regulators of cell growth and organ size. We show that EPS8, a signaling adapter regulating actin dynamics, is a novel partner of VE-cadherin and is able to modulate YAP activity. By biochemical and imaging approaches, we demonstrate that EPS8 associates with the VE-cadherin complex of remodeling junctions promoting YAP translocation to the nucleus and transcriptional activation. Conversely, in stabilized junctions, 14-3-3-YAP associates with the VE-cadherin complex, whereas Eps8 is excluded. Junctional association of YAP inhibits nuclear translocation and inactivates its transcriptional activity both in vitro and in vivo in Eps8-null mice. The absence of Eps8 also increases vascular permeability in vivo, but did not induce other major vascular defects. Collectively, we identified novel components of the adherens junction complex, and we introduce a novel molecular mechanism through which the VE-cadherin complex controls YAP transcriptional activity.
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Affiliation(s)
- Costanza Giampietro
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy Dipartimento di Bioscienze, Università degli Studi di Milano, 20122 Milan, Italy
| | - Andrea Disanza
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Luca Bravi
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Miriam Barrios-Rodiles
- Center for Systems Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Monica Corada
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | | | | | - Maria Grazia Lampugnani
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Barbara Boggetti
- Department of Dermatology, Cologne Excellence Cluster for Stress Responses in Ageing-Associated Diseases, Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Carien Niessen
- Department of Dermatology, Cologne Excellence Cluster for Stress Responses in Ageing-Associated Diseases, Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Jeff L Wrana
- Center for Systems Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Giorgio Scita
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy Dipartimento di Scienze della Salute, Università degli Studi di Milano, 20122 Milan, Italy
| | - Elisabetta Dejana
- FIRC Institute of Molecular Oncology, 20139 Milan, Italy Dipartimento di Bioscienze, Università degli Studi di Milano, 20122 Milan, Italy Department of Immunology, Genetics and Pathology, Uppsala University, 751 05 Uppsala, Sweden
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30
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Silencing of Eps8 inhibits in vitro angiogenesis. Life Sci 2015; 131:30-6. [DOI: 10.1016/j.lfs.2015.03.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 02/25/2015] [Accepted: 03/19/2015] [Indexed: 11/21/2022]
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Abstract
PURPOSE OF REVIEW The present review examines the role of actin binding proteins (ABPs) on blood-testis barrier (BTB), an androgen-dependent ultrastructure in the testis, in particular their involvement on BTB remodeling during spermatogenesis. RECENT FINDINGS The BTB divides the seminiferous epithelium into the basal and the adluminal compartments. The BTB is constituted by coexisting actin-based tight junction, basal ectoplasmic specialization, and gap junction, and also intermediate filament-based desmosome between Sertoli cells near the basement membrane. Junctions at the BTB undergo continuous remodeling to facilitate the transport of preleptotene spermatocytes residing in the basal compartment across the immunological barrier during spermatogenesis. Thus, meiosis I/II and postmeiotic spermatid development take place in the adluminal compartment behind the BTB. BTB remodeling also regulates exchanges of biomolecules between the two compartments. As tight junction, basal ectoplasmic specialization, and gap junction use F-actin for attachment, actin microfilaments rapidly convert between their bundled and unbundled/branched configuration to confer BTB plasticity. The events of actin reorganization are regulated by two major classes of ABPs that convert actin microfilaments between their bundled and branched/unbundled configuration. SUMMARY We provide a model on how ABPs regulate BTB remodeling, shedding new light on unexplained male infertility, such as environmental toxicant-induced reproductive dysfunction since the testis, in particular the BTB, is sensitive to environmental toxicants, such as cadmium, bisphenol A, phthalates, and PFOS (perfluorooctanesulfonic acid or perfluorooctane sulfonate).
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Affiliation(s)
- Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA
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Ding X, Yang Z, Zhou F, Hu X, Zhou C, Luo C, He Z, Liu Q, Li H, Yan F, Wang F, Xiang S, Zhang J. Human intersectin 2 (ITSN2) binds to Eps8 protein and enhances its degradation. BMB Rep 2014; 45:183-8. [PMID: 22449706 DOI: 10.5483/bmbrep.2012.45.3.183] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Participates in actin remodeling through Rac and receptor endocytosis via Rab5. Here, we used yeast two-hybrid system with Eps8 as bait to screen a human brain cDNA library. ITSN2 was identified as the novel binding factor of Eps8. The interaction between ITSN2 and Eps8 was demonstrated by the in vivo co-immunoprecipitation and colocalization assays and the in vitro GST pull-down assays. Furthermore, we mapped the interaction domains to the region between amino acids 260-306 of Eps8 and the coiled-coil domain of ITSN2. In addition, protein stability assays and immunofluorescence analysis showed ITSN2 overexpression induced the degradation of Eps8 proteins, which was markedly alleviated with the lysosome inhibitor NH4Cl treatment. Taken together, our results suggested ITSN2 interacts with Eps8 and stimulates the degradation of Eps8 proteins.
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Affiliation(s)
- Xiaofeng Ding
- Key Laboratory of Protein Chemistry and Development Biology of State Education Ministry of China, College of Life Science, Hunan Normal University, Changsha, China
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Human CD117 (cKit)+ innate lymphoid cells have a discrete transcriptional profile at homeostasis and are expanded during filarial infection. PLoS One 2014; 9:e108649. [PMID: 25255226 PMCID: PMC4177898 DOI: 10.1371/journal.pone.0108649] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 09/02/2014] [Indexed: 01/21/2023] Open
Abstract
Since innate lymphoid cells (ILCs) have been found to play a role in the immune response to helminth parasites in rodents, we sought to determine their role in human helminth infection. By developing multicolor flow cytometry-based methods to identify and enumerate circulating ILCs and their subsets, we were able to identify a subset of cKit+ ILCs defined as Lineage (Lin)-/CD45+/cKit+/CD127+ that were significantly expanded in the filarial-infected individuals (p=0.0473) as were those cKit+ ILCs that produced IL-13. Additionally, the frequency of these cKit+ ILCs correlated with the frequency of IL-17 producing CD4+ T cells (Th17 cells; p=0.025). To investigate the function of cKit+ ILCs, sorted, highly purified human ILCs were subjected to transcriptional profiling by RNAseq and compared to appropriate control cells. These cKit+ ILCs expressed TLRs, a broad range of cytokines/cytokine receptors and MHC Class II molecules suggesting that these ILCs sense pathogens independent of other cell types. Functional analysis revealed expanded cKit+ ILC-specific transcription and ILC-specific microRNA precursors.
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Li YH, Xue TY, He YZ, Du JW. Novel oncoprotein EPS8: a new target for anticancer therapy. Future Oncol 2014; 9:1587-94. [PMID: 24106906 DOI: 10.2217/fon.13.104] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
EPS8 was first identified as a tyrosine kinase substrate, that plays a role in EGFR-mediated mitogenic signaling. Recent research has shown that EPS8 is overexpressed in most types of cancer, for example breast cancer, colon cancer, cervical cancer and even hematologic malignancies. EPS8 is involved in many signaling pathways related to tumorigenesis, proliferation, migration and metastasis, and is a biomarker for poor prognosis of cancer patients. This review aims to provide a comprehensive picture of the role of EPS8 in cellular processes and its significance to tumorigenesis. Furthermore, this review focuses on the potential role of EPS8 as a therapeutic cancer target.
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Affiliation(s)
- Yu-Hua Li
- Department of Hematology, Zhujiang Hospital, Southern Medical University, 510282 Guangzhou, China
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Abstract
The transport of germ cells across the seminiferous epithelium is composed of a series of cellular events during the epithelial cycle essential to the completion of spermatogenesis. Without the timely transport of spermatids during spermiogenesis, spermatozoa that are transformed from step 19 spermatids in the rat testis fail to reach the luminal edge of the apical compartment and enter the tubule lumen at spermiation, thereby arriving the epididymis for further maturation. Step 19 spermatids and/or sperms that remain in the epithelium beyond stage VIII of the epithelial cycle will be removed by the Sertoli cell via phagocytosis to form phagosomes and be degraded by lysosomes, leading to subfertility and/or infertility. However, the biology of spermatid transport, in particular the final events that lead to spermiation remain elusive. Based on recent data in the field, we critically evaluate the biology of spermiation herein by focusing on the actin binding proteins (ABPs) that regulate the organization of actin microfilaments at the Sertoli-spermatid interface, which is crucial for spermatid transport during this event. The hypothesis we put forth herein also highlights some specific areas of research that can be pursued by investigators in the years to come.
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Cheng CY, Lie PPY, Wong EWP, Mruk DD. Focal adhesion kinase and actin regulatory/binding proteins that modulate F-actin organization at the tissue barrier: Lesson from the testis. Tissue Barriers 2014; 1:e24252. [PMID: 24665388 PMCID: PMC3875635 DOI: 10.4161/tisb.24252] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 03/07/2013] [Accepted: 03/09/2013] [Indexed: 11/28/2022] Open
Abstract
Focal adhesion kinase (FAK), as its name implied, is an important mediator of integrin-based signaling function in mammalian cells at the focal adhesion complex (FAC, also known as focal contact) at the cell-extracellular matrix interface. FAK is intimately related to cell movement, such as in macrophages, fibroblasts and also tumor cells. In the testis, however, FAK and two of its phosphorylated forms, p-FAK-Tyr407 and -Tyr397, are not found at the FAC since there is no ultrastructure analogous or similar to FAC in the mammalian testis vs. other epithelia. Instead, FAK and its two phosphorylated forms are detected along the seminiferous epithelium in the rat testis at the cell-cell interface in a testis-specific adherens junction (AJ) known as the ectoplasmic specialization (ES). ES is an F-actin-rich ultrastructure in which bundles of actin filaments are sandwiched in-between plasma membrane and cisternae of endoplasmic reticulum not found in other mammalian epithelial/endothelial cells. The ES is restricted to the interface of Sertoli cells and spermatids (step 8–19) known as the apical ES, and to the Sertoli cell-cell interface known as the basal ES. Interestingly, the basal ES is also an integrated component of the blood-testis barrier (BTB), coexisting with tight junction (TJ) and gap junction (GJ), and it is conceivable that actin filament bundles at the ES undergo extensive organization, converting from their “bundled” to “de-bundled/branching” configuration to facilitate transport of germ cells across the epithelium and at the BTB during the epithelial cycle. A recent report (Lie et al. PNAS 109:12562–12567, 2012) has demonstrated that the stage-specific and spatiotemporal expression of p-FAK-Tyr407 and -Tyr397 are crucial to the regulation of these events via their stage-specific and spatiotemporal expression during the epithelial cycle mediated by their effects on the organization of the actin filament bundles at the ES, involving actin binding/regulatory proteins. In this Commentary, we will critically evaluate these findings in light of other recent reports in the field. While these ideas are based on studies in the BTB in the rat testis, this information should be applicable and helpful to investigators studying other tissue barriers.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
| | - Pearl P Y Lie
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
| | - Elissa W P Wong
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
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Gungor-Ordueri NE, Mruk DD, Wan HT, Wong EWP, Celik-Ozenci C, Lie PPY, Cheng CY. New insights into FAK function and regulation during spermatogenesis. Histol Histopathol 2014; 29:977-89. [PMID: 24578181 DOI: 10.14670/hh-29.977] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Germ cell transport across the seminiferous epithelium during the epithelial cycle is crucial to spermatogenesis, although molecular mechanism(s) that regulate these events remain unknown. Studies have shown that spatiotemporal expression of crucial regulatory proteins during the epithelial cycle represents an efficient and physiologically important mechanism to regulate spermatogenesis without involving de novo synthesis of proteins and/or expression of genes. Herein, we critically review the role of focal adhesion kinase (FAK) in coordinating the transport of spermatids and preleptotene spermatocytes across the epithelium and the BTB, respectively, along the apical ectoplasmic specialization (ES) - blood-testis barrier - basement membrane (BM) functional axis during spermatogenesis. In the testis, p-FAK-Tyr³⁸⁷ and p-FAK-Tyr⁴⁰⁷ are spatiotemporally expressed during the epithelial cycle at the actin-rich anchoring junction known as ES, regulating cell adhesion at the Sertoli-spermatid (apical ES) and Sertoli cell-cell (basal ES) interface. Phosphorylated forms of FAK exert their effects by regulating the homeostasis of F-actin at the ES, mediated via their effects on actin polymerization so that microfilaments are efficiently re-organized, such as from their "bundled" to "de-bundled/branched" configuration and vice versa during the epithelial cycle to facilitate the transport of: (i) spermatids across the epithelium, and (ii) preleptotene spermatocytes across the BTB. In summary, p-FAK-Tyr⁴⁰⁷ and p-FAK-Tyr³⁸⁷ are important regulators of spermatogenesis which serve as molecular switches that turn "on" and "off" adhesion function at the apical ES and the basal ES/BTB, mediated via their spatiotemporal expression during the epithelial cycle. A hypothetical model depicting the role of these two molecular switches is also proposed.
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Affiliation(s)
- N Ece Gungor-Ordueri
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Hin-ting Wan
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Elissa W P Wong
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Ciler Celik-Ozenci
- Department of Histology and Embryology, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Pearl P Y Lie
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA. OR
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Huang CC, Lin YS, Lee CC, Hsu KS. Cell type-specific expression of Eps8 in the mouse hippocampus. BMC Neurosci 2014; 15:26. [PMID: 24533597 PMCID: PMC3937003 DOI: 10.1186/1471-2202-15-26] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 02/13/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Epidermal growth factor receptor substrate 8 (Eps8) is a multifunctional protein that regulates actin cytoskeleton dynamics and architecture through its barbed-end capping and bundling activities. In cultured hippocampal neurons, Eps8 is enriched at dendritic spine heads and is required for spine morphogenesis; however, the detailed expression pattern of Eps8 in the hippocampus has not yet been explored. RESULTS Here, we demonstrate that endogenous Eps8 protein is restrictively expressed in neurons (NeuN-positive), but not in glial cells (glial fibrillary acidic protein-positive) in area CA1 of the mouse hippocampus. Surprisingly, Eps8 immunoreactivity is rarely found in pyramidal cell somata, but is expressed predominantly in the somata and dendrites of 67 kDa isoform of glutamic acid decarboxylase-expressing GABAergic interneurons in the stratum radiatum and at the border of stratum radiatum and lacunosum-moleculare of area CA1. On the basis of co-localizing markers, we found that Eps8 is not present in perisomatic inhibitory parvalbumin-expressing cells or calretinin-expressing interneurons. However, Eps8 is richly expressed in calbindin-expressing interneurons. Furthermore, Eps8 is also present in cholecystokinin-expressing interneurons, but not in somatostatin-expressing interneurons in area CA1 stratum pyramidale and stratum radiatum. CONCLUSIONS These results reveal a previously unknown cell type-specific expression pattern of endogenous Eps8 protein in the mouse hippocampus and speculate that the role of Eps8 in controlling and orchestrating neuronal morphogenesis and structural plasticity might be more prominent in interneurons than in pyramidal cells of the hippocampus.
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Affiliation(s)
| | | | | | - Kuei-Sen Hsu
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan.
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Werner A, Disanza A, Reifenberger N, Habeck G, Becker J, Calabrese M, Urlaub H, Lorenz H, Schulman B, Scita G, Melchior F. SCFFbxw5 mediates transient degradation of actin remodeller Eps8 to allow proper mitotic progression. Nat Cell Biol 2013; 15:179-88. [PMID: 23314863 DOI: 10.1038/ncb2661] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 11/26/2012] [Indexed: 12/22/2022]
Abstract
Eps8, a bi-functional actin cytoskeleton remodeller, is a positive regulator of cell proliferation and motility. Here, we describe an unrecognized mechanism regulating Eps8 that is required for proper mitotic progression: whereas Eps8 is stable in G1 and S phase, its half-life drops sharply in G2. This requires G2-specific proteasomal degradation mediated by the ubiquitin E3 ligase SCF(Fbxw5). Consistent with a short window of degradation, Eps8 disappears from the cell cortex early in mitosis, but reappears at the midzone of dividing cells. Failure to reduce Eps8 levels in G2 prolongs its localization at the cell cortex and markedly delays cell rounding and prometaphase duration. However, during late stages of mitosis and cytokinesis, Eps8 capping activity is required to prevent membrane blebbing and cell-shape deformations. Our findings identify SCF(Fbxw5)-driven fluctuation of Eps8 levels as an important mechanism that contributes to cell-shape changes during entry into-and exit from-mitosis.
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Affiliation(s)
- Achim Werner
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, Germany.
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Auciello G, Cunningham DL, Tatar T, Heath JK, Rappoport JZ. Regulation of fibroblast growth factor receptor signalling and trafficking by Src and Eps8. J Cell Sci 2012. [PMID: 23203811 DOI: 10.1242/jcs.116228] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Fibroblast growth factor receptors (FGFRs) mediate a wide spectrum of cellular responses that are crucial for development and wound healing. However, aberrant FGFR activity leads to cancer. Activated growth factor receptors undergo stimulated endocytosis, but can continue to signal along the endocytic pathway. Endocytic trafficking controls the duration and intensity of signalling, and growth factor receptor signalling can lead to modifications of trafficking pathways. We have developed live-cell imaging methods for studying FGFR dynamics to investigate mechanisms that coordinate the interplay between receptor trafficking and signal transduction. Activated FGFR enters the cell following recruitment to pre-formed clathrin-coated pits (CCPs). However, FGFR activation stimulates clathrin-mediated endocytosis; FGF treatment increases the number of CCPs, including those undergoing endocytosis, and this effect is mediated by Src and its phosphorylation target Eps8. Eps8 interacts with the clathrin-mediated endocytosis machinery and depletion of Eps8 inhibits FGFR trafficking and immediate Erk signalling. Once internalized, FGFR passes through peripheral early endosomes en route to recycling and degredative compartments, through an Src- and Eps8-dependent mechanism. Thus Eps8 functions as a key coordinator in the interplay between FGFR signalling and trafficking. This work provides the first detailed mechanistic analysis of growth factor receptor clustering at the cell surface through signal transduction and endocytic trafficking. As we have characterised the Src target Eps8 as a key regulator of FGFR signalling and trafficking, and identified the early endocytic system as the site of Eps8-mediated effects, this work provides novel mechanistic insight into the reciprocal regulation of growth factor receptor signalling and trafficking.
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Affiliation(s)
- Giulio Auciello
- CRUK Growth Factor Group, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Rubinfeld H, Shimon I. PI3K/Akt/mTOR and Raf/MEK/ERK signaling pathways perturbations in non-functioning pituitary adenomas. Endocrine 2012; 42:285-91. [PMID: 22552912 DOI: 10.1007/s12020-012-9682-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 04/17/2012] [Indexed: 12/14/2022]
Abstract
Non-functioning pituitary adenomas (NFPAs) comprise a heterogeneous group, which are considered the most common pituitary tumor. As no clinically hormone hypersecretion is apparent, non-functioning pituitary adenomas are often diagnosed only when they are large enough to cause tumor mass effects, such as hypopituitarism, visual field defects or headaches. Efficient medical therapy for NFPAs is currently unavailable and surgical treatment of these tumors is not always satisfactory. Characterization of signaling regulatory events in the context of NFPAs may enable the development of new attractive novel strategies. Although data regarding gene expression profiling of signaling pathways in NFPAs have accumulated, studies aimed at fine-classification of NFPAs-specific signaling regulatory mechanisms and feedback loops are scarce.
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Affiliation(s)
- Hadara Rubinfeld
- Institute of Endocrinology and Metabolism and Felsenstein Medical Research Center, Rabin Medical Center, Beilinson Campus and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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Cattaneo MG, Cappellini E, Vicentini LM. Silencing of Eps8 blocks migration and invasion in human glioblastoma cell lines. Exp Cell Res 2012; 318:1901-12. [PMID: 22683923 DOI: 10.1016/j.yexcr.2012.05.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 05/09/2012] [Accepted: 05/14/2012] [Indexed: 11/30/2022]
Abstract
Glioblastoma multiforme (GBM) is the most malignant human primary brain tumor, and its infiltrative nature represents the leading cause for the failure of therapies and tumor recurrences. It is therefore crucial the knowledge of the molecular mechanisms underlying GBM invasion to identify novel therapeutic targets to limit motility. In this study, we evaluated the role of Epidermal growth factor receptor Pathway Substrate 8 (Eps8), a crucial regulator of the actin cytoskeleton dynamics accompanying cell motility and invasion, in GBM migration and invasiveness. We found that silencing of the protein by small interfering RNAs (siRNAs) abrogated the migratory and invasive capacity of three different human GBM cell lines both in 2-dimensional (2-D) and 3-dimensional (3-D) in vitro assays. The inhibitory effect on invasion was maintained independently by the migration mode utilized by the cells in our 3-D model, and was accompanied by an impaired formation of actin-based cytoskeletal protrusive structures. Our data propose Eps8 as a key molecule involved in the control of the intrinsic invasive behavior of GBM cells, and suggest that this protein might represent a useful target for the design of new drugs for the treatment of these tumors.
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Affiliation(s)
- Maria Grazia Cattaneo
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Via Vanvitelli 32, 20129 Milano, Italy
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43
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Chen YJ, Hsieh MY, Chang MY, Chen HC, Jan MS, Maa MC, Leu TH. Eps8 protein facilitates phagocytosis by increasing TLR4-MyD88 protein interaction in lipopolysaccharide-stimulated macrophages. J Biol Chem 2012; 287:18806-19. [PMID: 22493489 DOI: 10.1074/jbc.m112.340935] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Toll-like receptors (TLRs) are crucial in macrophage phagocytosis, which is pivotal in host innate immune response. However, the detailed mechanism is not fully defined. Here, we demonstrated that the induction of Src and Eps8 in LPS-treated macrophages was TLR4- and MyD88-dependent, and their attenuation reduced LPS-promoted phagocytosis. Confocal microscopy indicated the colocalization of Eps8 and TLR4 in the cytosol and at the phagosome. Consistently, both Eps8 and TLR4 were present in the same immunocomplex regardless of LPS stimulation. Inhibition of this complex formation by eps8 siRNA or overexpression of pleckstrin homology domain-truncated Eps8 (i.e. 261-p97(Eps8)) decreased LPS-induced TLR4-MyD88 interaction and the following activation of Src, focal adhesion kinase, and p38 MAPK. Importantly, attenuation of Eps8 impaired the bacterium-killing ability of macrophages. Thus, Eps8 is a key regulator of the LPS-stimulated TLR4-MyD88 interaction and contributes to macrophage phagocytosis.
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Affiliation(s)
- Yen-Jen Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
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Selva J, Egea G. Ethanol increases p190RhoGAP activity, leading to actin cytoskeleton rearrangements. J Neurochem 2011; 119:1306-16. [PMID: 21985251 DOI: 10.1111/j.1471-4159.2011.07522.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We previously reported that cells chronically exposed to ethanol show alterations in actin cytoskeleton organization and dynamics in primary cultures of newborn rat astrocytes, a well-established in vitro model for foetal alcohol spectrum disorders. These alterations were attributed to a decrease in the cellular levels of active RhoA (RhoA-GTP), which in turn was produced by an increase in the total RhoGAP activity. We here provide evidence that p190RhoGAPs are the main factors responsible for such increase. Thus, in astrocytes chronically exposed to ethanol we observe: (i) an increase in p190A- and p190B-associated RhoGAP activity; (ii) a higher binding of p190A and p190B to RhoA-GTP; (iii) a higher p120RasGAP-p190A RhoGAP complex formation; and (iv) the recruitment of both p190RhoGAPs to the plasma membrane. The simultaneous silencing of both p190 isoforms prevents the actin rearrangements and the total RhoGAP activity increase triggered both by ethanol. Therefore, our data directly points p190RhoGAPs as ethanol-exposure molecular targets on glial cells of the CNS.
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Affiliation(s)
- Javier Selva
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, and Instituts d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, Barcelona, Spain
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Pierre S, Bats AS, Coumoul X. Understanding SOS (Son of Sevenless). Biochem Pharmacol 2011; 82:1049-56. [PMID: 21787760 DOI: 10.1016/j.bcp.2011.07.072] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Revised: 07/02/2011] [Accepted: 07/05/2011] [Indexed: 10/17/2022]
Abstract
Son of Sevenless (SOS) was discovered in Drosophila melanogaster. Essential for normal eye development in Drosophila, SOS has two human homologues, SOS1 and SOS2. The SOS1 gene encodes the Son of Sevenless 1 protein, a Ras and Rac guanine nucleotide exchange factor. This protein is composed of several important domains. The CDC25 and REM domains provide the catalytic activity of SOS1 towards Ras and the histone fold DH/PH (Dbl homology and Pleckstrin homology) domains function, in tandem, to stimulate GTP/GDP exchange for Rac. In contrast to Ras, there have been few studies that implicate SOS1 in human disease and, initially, less attention was given to this gene. However, mutations in SOS1 have been reported recently in Noonan syndrome and in type 1 hereditary gingival fibromatosis. Although, there have been very few studies that focus on the regulation of this important gene by physiological or exogenous factors, we recently found that the SOS1 gene was induced by the environmental toxin, dioxin, and that this effect was mediated by the aryl hydrocarbon receptor (AhR). These recent observations raise the possibility that alterations in the expression of the SOS1 gene and, consequently, in the activity of the SOS1 protein may affect toxicological endpoints and lead to clinical disease. These possibilities, thus, have stimulated much interest in SOS1 recently. In this article, we review the functions of SOS1 and the evidence for its roles in physiology and pathology across species.
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Affiliation(s)
- Stéphane Pierre
- INSERM UMR-S 747, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, 75006 Paris, France
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Regulation of spermiogenesis, spermiation and blood-testis barrier dynamics: novel insights from studies on Eps8 and Arp3. Biochem J 2011; 435:553-62. [PMID: 21486226 DOI: 10.1042/bj20102121] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Spermiogenesis in the mammalian testis is the most critical post-meiotic developmental event occurring during spermatogenesis in which haploid spermatids undergo extensive cellular, molecular and morphological changes to form spermatozoa. Spermatozoa are then released from the seminiferous epithelium at spermiation. At the same time, the BTB (blood-testis barrier) undergoes restructuring to facilitate the transit of preleptotene spermatocytes from the basal to the apical compartment. Thus meiotic divisions take place behind the BTB in the apical compartment to form spermatids. These germ cells enter spermiogenesis to transform into elongating spermatids and then into spermatozoa to replace those that were released in the previous cycle. However, the mole-cular regulators that control spermiogenesis, in particular the dynamic changes that occur at the Sertoli cell-spermatid interface and at the BTB, are not entirely known. This is largely due to the lack of suitable animal models which can be used to study these events. During the course of our investigation to develop adjudin [1-(2,4-dichlorobenzyl)-1H-indazole-3-carbohydrazide] as a potential male contraceptive, this drug was shown to 'accelerate' spermiation by inducing the release of premature spermatids from the epithelium. Using this model, we have identified several molecules that are crucial in regulating the actin filament network and the unique adhesion protein complex at the Sertoli cell-spermatid interface known as the apical ES (ectoplasmic specialization). In the present review, we critically evaluate these and other findings in the literature as they relate to the restricted temporal and spatial expression of two actin regulatory proteins, namely Eps8 (epidermal growth factor receptor pathway substrate 8) and Arp3 (actin-related protein 3), which regulate these events.
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Zampini V, Rüttiger L, Johnson SL, Franz C, Furness DN, Waldhaus J, Xiong H, Hackney CM, Holley MC, Offenhauser N, Di Fiore PP, Knipper M, Masetto S, Marcotti W. Eps8 regulates hair bundle length and functional maturation of mammalian auditory hair cells. PLoS Biol 2011; 9:e1001048. [PMID: 21526224 PMCID: PMC3079587 DOI: 10.1371/journal.pbio.1001048] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 03/09/2011] [Indexed: 12/20/2022] Open
Abstract
Hair cells of the mammalian cochlea are specialized for the dynamic coding of sound stimuli. The transduction of sound waves into electrical signals depends upon mechanosensitive hair bundles that project from the cell's apical surface. Each stereocilium within a hair bundle is composed of uniformly polarized and tightly packed actin filaments. Several stereociliary proteins have been shown to be associated with hair bundle development and function and are known to cause deafness in mice and humans when mutated. The growth of the stereociliar actin core is dynamically regulated at the actin filament barbed ends in the stereociliary tip. We show that Eps8, a protein with actin binding, bundling, and barbed-end capping activities in other systems, is a novel component of the hair bundle. Eps8 is localized predominantly at the tip of the stereocilia and is essential for their normal elongation and function. Moreover, we have found that Eps8 knockout mice are profoundly deaf and that IHCs, but not OHCs, fail to mature into fully functional sensory receptors. We propose that Eps8 directly regulates stereocilia growth in hair cells and also plays a crucial role in the physiological maturation of mammalian cochlear IHCs. Together, our results indicate that Eps8 is critical in coordinating the development and functionality of mammalian auditory hair cells.
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Affiliation(s)
- Valeria Zampini
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
- Department of Physiology, University of Pavia, Pavia, Italy
| | - Lukas Rüttiger
- Department of Otolaryngology, THR, University of Tübingen, Tübingen, Germany
| | - Stuart L. Johnson
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Christoph Franz
- Department of Otolaryngology, THR, University of Tübingen, Tübingen, Germany
| | - David N. Furness
- Institute for Science and Technology in Medicine, Keele University, Keele, United Kingdom
| | - Jörg Waldhaus
- Department of Otolaryngology, THR, University of Tübingen, Tübingen, Germany
| | - Hao Xiong
- Department of Otolaryngology, THR, University of Tübingen, Tübingen, Germany
- Department of Otolaryngology-Head & Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Carole M. Hackney
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Matthew C. Holley
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Nina Offenhauser
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - Pier Paolo Di Fiore
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
- Istituto Europeo di Oncologia, Milan, Italy
- Dipartimento di Medicina, Chirurgia e Odontoiatria, Università degli Studi di Milano, Milan, Italy
| | - Marlies Knipper
- Department of Otolaryngology, THR, University of Tübingen, Tübingen, Germany
| | - Sergio Masetto
- Department of Physiology, University of Pavia, Pavia, Italy
- * E-mail: (WM); (SM)
| | - Walter Marcotti
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
- * E-mail: (WM); (SM)
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Abstract
The MTM (myotubularin)/MTMR (myotubularin-related) protein family is comprised of 15 lipid phosphatases, of which nine members are catalytically active. MTMs are known to play a fundamental role in human physiology as gene mutations can give rise to X-linked myotubular myopathy or Charcot-Marie-Tooth disease, which manifest in skeletal muscle or in peripheral neurons respectively. Interestingly, studies have shown MTMR2 and MTMR5, two MTM family members, to be highly expressed in the testis, particularly in Sertoli and germ cells, and knockout of either gene resulted in spermatogenic defects. Other studies have shown that MTMR2 functions in endocytosis and membrane trafficking. In the testis, MTMR2 interacts and co-localizes with c-Src/phospho-Src-(Tyr⁴¹⁶), a non-receptor protein tyrosine kinase that regulates the phosphorylation state of proteins at the apical ES (ectoplasmic specialization), a unique type of cell junction found between Sertoli cells and elongating/elongated spermatids. In the present review, we highlight recent findings that have made a significant impact on our understanding of this protein family in normal cell function and in disease, with the emphasis on the role of MTMs and MTMRs in spermatogenesis. We also describe a working model to explain how MTMR2 interacts with other proteins such as c-Src, dynamin 2, EPS8 (growth factor receptor pathway substrate 8) and ARP2/3 (actin-related protein 2/3) at the apical ES and the apical TBC (tubulobulbar complex; tubular-like invaginations that function in the disassembly of the apical ES and in the recycling of its components) to regulate spermiation at late stage VIII of the seminiferous epithelial cycle.
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Abstract
Insulin-like growth factor 2 (IGF-2) mRNA-binding proteins (IMPs) are a family of posttranscriptional regulatory factors with well-understood roles in embryonic development and cancer but with poorly characterized functions in normal adult cells and tissues. We now show that IMP-2, the most ubiquitously expressed member of the family, is abundant in human and mouse adult skeletal myoblasts, where it is indispensable for cell motility and for stabilization of microtubules. To explore the functions of IMP-2, we analyzed the transcripts that were differentially regulated in IMP-2-depleted myoblasts and bound to IMP-2 in normal myoblasts. Among them were the mRNAs of PINCH-2, an important mediator of cell adhesion and motility, and MURF-3, a microtubule-stabilizing protein. By gain- and loss-of-function assays and gel shift experiments, we show that IMP-2 regulates the expression of PINCH-2 and MURF-3 proteins via direct binding to their mRNAs. Upregulation of PINCH-2 in IMP-2-depleted myoblasts is the key event responsible for their decreased motility. Our data reveal how the posttranscriptional regulation of gene expression by IMP-2 contributes to the control of adhesion structures and stable microtubules and demonstrate an important function for IMP-2 in cellular motility.
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Si FC. Effects of Qigesan, Shashenmaidongtang, Tongyoutang and Buqiyunpitang on hEGF-stimulated proliferation of human esophageal carcinoma EC9706 cells. Shijie Huaren Xiaohua Zazhi 2010; 18:2956-2965. [DOI: 10.11569/wcjd.v18.i28.2956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effects of Qigesan, Shashenmaidongtang, Tongyoutang and Buqiyunpitang on the proliferation of human esophageal carcinoma EC9706 cells stimulated with human epidermal growth factor (hEGF), and to explore potential mechanisms involved.
METHODS: After cultured EC9706 cells were stimulated with hEGF and then treated with Qigesan, Shashenmaidongtang, Tongyoutang and Buqiyunpitang, respectively, cell morphological changes were observed under an inverted microscope, cell proliferation was determined by MTT assay, cell cycle progression was measured by flow cytometry, and protein expression and tyrosine phosphorylation in PLC-γ1 and PI3K-mediated signaling pathways were determined by Western blot.
RESULTS: The half-maximum inhibitory concentrations (IC50) of Qigesan, Shashenmaidongtang and Tongyoutang were 849, 1 004 and 1 615 mg/L, respectively. These drugs at a concentration of IC50 inhibited hEGF-stimulated cell proliferation and prevented cell cycle progression into S phase. Buqiyunpitang could only weakly inhibit the proliferation of EC9706 cells. Qigesan, Shashenmaidongtang and Tongyoutang inhibited the protein expression and tyrosine phosphorylation of EGFR and PLC-γ1 as well as the protein expression of PKCα, MARCKS, PI3K, AKT-1 and NF-κB p50. Tongyoutang had the strongest inhibitory effects on the PLC-γ1 signaling pathway, followed by Qigesan and Shashenmaidongtang. In contrast, the order of the inhibitory potency for the PI3K signaling pathway was Tongyoutang, Shashenmaidongtang and Qigesan.
CONCLUSION: Qigesan, Shashenmaidongtang and Tongyoutang can, to varying degrees, inhibit hEGF-stimulated cell proliferation by suppressing PLC-γ1 and PI3K-mediated signaling pathways.
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