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Catalán-Castorena O, Garibay-Cerdenares OL, Illades-Aguiar B, Castillo-Sánchez R, Zubillaga-Guerrero MI, Leyva-Vazquez MA, Encarnacion-Guevara S, Flores-Alfaro E, Ramirez-Ruano M, del Carmen Alarcón-Romero L. Bioinformatics Analysis of Human Papillomavirus 16 Integration in Cervical Cancer: Changes in MAGI-1 Expression in Premalignant Lesions and Invasive Carcinoma. Cancers (Basel) 2024; 16:2225. [PMID: 38927930 PMCID: PMC11202195 DOI: 10.3390/cancers16122225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 06/05/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024] Open
Abstract
HPV 16 integration is crucial for the onset and progression of premalignant lesions to invasive squamous cell carcinoma (ISCC) because it promotes the amplification of proto-oncogenes and the silencing of tumor suppressor genes; some of these are proteins with PDZ domains involved in homeostasis and cell polarity. Through a bioinformatics approach based on interaction networks, a group of proteins associated with HPV 16 infection, PDZ domains, and direct physical interaction with E6 and related to different hallmarks of cancer were identified. MAGI-1 was selected to evaluate the expression profile and subcellular localization changes in premalignant lesions and ISCC with HPV 16 in an integrated state in cervical cytology; the profile expression of MAGI-1 diminished according to lesion grade. Surprisingly, in cell lines CaSki and SiHa, the protein localization was cytoplasmic and nuclear. In contrast, in histological samples, a change in subcellular localization from the cytoplasm in low-grade squamous intraepithelial lesions (LSIL) to the nucleus in the high-grade squamous intraepithelial lesion (HSIL) was observed; in in situ carcinomas and ISCC, MAGI-1 expression was absent. In conclusion, MAGI-1 expression could be a potential biomarker for distinguishing those cells with normal morphology but with HPV 16 integrated from those showing morphology-related uterine cervical lesions associated with tumor progression.
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Affiliation(s)
- Oscar Catalán-Castorena
- Cytopathology and Histochemistry Research Laboratory, Faculty of Chemical and Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico; (O.C.-C.); (M.I.Z.-G.)
| | - Olga Lilia Garibay-Cerdenares
- Molecular Biomedicine Laboratory, Faculty of Chemical-Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico; (B.I.-A.); (M.A.L.-V.)
- CONAHCyT-Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico
| | - Berenice Illades-Aguiar
- Molecular Biomedicine Laboratory, Faculty of Chemical-Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico; (B.I.-A.); (M.A.L.-V.)
| | - Rocio Castillo-Sánchez
- Cell Biology Department, CINVESTAV-IPN Research Institute, Ciudad de México 07360, Mexico;
| | - Ma. Isabel Zubillaga-Guerrero
- Cytopathology and Histochemistry Research Laboratory, Faculty of Chemical and Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico; (O.C.-C.); (M.I.Z.-G.)
| | - Marco Antonio Leyva-Vazquez
- Molecular Biomedicine Laboratory, Faculty of Chemical-Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico; (B.I.-A.); (M.A.L.-V.)
| | - Sergio Encarnacion-Guevara
- Center for Genomic Sciences, National Autonomous University of Mexico, Cuernavaca 62210, Morelos, Mexico;
| | - Eugenia Flores-Alfaro
- Clinical and Molecular Epidemiology Research Laboratory, Faculty of Chemical-Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico;
| | - Mónica Ramirez-Ruano
- Functional Genomics and Proteomics Laboratory, Faculty of Chemical-Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico;
| | - Luz del Carmen Alarcón-Romero
- Cytopathology and Histochemistry Research Laboratory, Faculty of Chemical and Biological Sciences, Autonomous University of Guerrero, Chilpancingo 39070, Guerrero, Mexico; (O.C.-C.); (M.I.Z.-G.)
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2
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Javorsky A, Humbert PO, Kvansakul M. Viral manipulation of cell polarity signalling. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119536. [PMID: 37437846 DOI: 10.1016/j.bbamcr.2023.119536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/24/2023] [Accepted: 07/04/2023] [Indexed: 07/14/2023]
Abstract
Cell polarity refers to the asymmetric distribution of biomacromolecules that enable the correct orientation of a cell in a particular direction. It is thus an essential component for appropriate tissue development and function. Viral infections can lead to dysregulation of polarity. This is associated with a poor prognosis due to viral interference with core cell polarity regulatory scaffolding proteins that often feature PDZ (PSD-95, DLG, and ZO-1) domains including Scrib, Dlg, Pals1, PatJ, Par3 and Par6. PDZ domains are also promiscuous, binding to several different partners through their C-terminal region which contain PDZ-binding motifs (PBM). Numerous viruses encode viral effector proteins that target cell polarity regulators for their benefit and include papillomaviruses, flaviviruses and coronaviruses. A better understanding of the mechanisms of action utilised by viral effector proteins to subvert host cell polarity sigalling will provide avenues for future therapeutic intervention, while at the same time enhance our understanding of cell polarity regulation and its role tissue homeostasis.
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Affiliation(s)
- Airah Javorsky
- Department of Biochemistry & Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Patrick O Humbert
- Department of Biochemistry & Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia; Research Centre for Molecular Cancer Prevention, La Trobe University, Melbourne, Victoria 3086, Australia; Department of Biochemistry & Pharmacology, University of Melbourne, Melbourne, Victoria 3010, Australia; Department of Clinical Pathology, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Marc Kvansakul
- Department of Biochemistry & Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia; Research Centre for Molecular Cancer Prevention, La Trobe University, Melbourne, Victoria 3086, Australia.
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Dizanzo MP, Bugnon Valdano M, Basukala O, Banks L, Gardiol D. Novel effect of the high risk-HPV E7 CKII phospho-acceptor site on polarity protein expression. BMC Cancer 2022; 22:1015. [PMID: 36153517 PMCID: PMC9509620 DOI: 10.1186/s12885-022-10105-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 09/19/2022] [Indexed: 11/10/2022] Open
Abstract
Background Oncogenic Human Papillomaviruses (HPVs) base their transforming potential on the action of both E6 and E7 viral oncoproteins, which perform cooperative or antagonistic actions and thus interfere with a variety of relevant cellular targets. Among them, the expression of some PDZ-containing polarity proteins, as DLG1 and hScrib, is altered during the HPV life cycle and the consequent malignant transformation. Together with the well-established interference of E6 with PDZ proteins, we have recently shown that E7 viral oncoprotein is also responsible for the changes in abundance and localization of DLG1 observed in HPV-associated lesions. Given that the mechanisms involved remained only partially understood, we here thoroughly analyse the contribution of a crucial E7 post-translational modification: its CKII-dependent phosphorylation. Moreover, we extended our studies to hScrib, in order to investigate possible conserved regulatory events among diverse PDZ targets of HPV. Methods We have acutely analysed the expression of DLG1 and hScrib in restrictive conditions for E7 phosphorylation by CKII in epithelial culture cells by western blot and confocal fluorescence microscopy. We made use of genome-edited HPV-positive cells, specific inhibitors of CKII activity and transient expression of the viral oncoproteins, including a mutant version of E7. Results We here demonstrate that the functional phosphorylation of E7 oncoprotein by the CKII cellular kinase, a key regulatory event for its activities, is also crucial to counteract the E6-mediated degradation of the PDZ-polarity protein DLG1 and to promote its subcellular redistribution. Moreover, we show that the CKII-dependent phosphorylation of E7 is able to control the expression of another PDZ target of HPV: hScrib. Remarkably, we found this is a shared feature among different oncogenic HPV types, suggesting a common path towards viral pathogenesis. Conclusions The present study sheds light into the mechanisms behind the misexpression of PDZ-polarity proteins during HPV infections. Our findings stress the relevance of the CKII-mediated regulation of E7 activities, providing novel insights into the joint action of HPV oncoproteins and further indicating a conserved and most likely crucial mechanism during the viral life cycle and the associated transformation. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-022-10105-5.
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Tessier TM, Dodge MJ, MacNeil KM, Evans AM, Prusinkiewicz MA, Mymryk JS. Almost famous: Human adenoviruses (and what they have taught us about cancer). Tumour Virus Res 2021; 12:200225. [PMID: 34500123 PMCID: PMC8449131 DOI: 10.1016/j.tvr.2021.200225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/25/2021] [Accepted: 09/03/2021] [Indexed: 12/11/2022] Open
Abstract
Papillomaviruses, polyomaviruses and adenoviruses are collectively categorized as the small DNA tumour viruses. Notably, human adenoviruses were the first human viruses demonstrated to be able to cause cancer, albeit in non-human animal models. Despite their long history, no human adenovirus is a known causative agent of human cancers, unlike a subset of their more famous cousins, including human papillomaviruses and human Merkel cell polyomavirus. Nevertheless, seminal research using human adenoviruses has been highly informative in understanding the basics of cell cycle control, gene expression, apoptosis and cell differentiation. This review highlights the contributions of human adenovirus research in advancing our knowledge of the molecular basis of cancer.
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Affiliation(s)
- Tanner M Tessier
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Mackenzie J Dodge
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Katelyn M MacNeil
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Andris M Evans
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Martin A Prusinkiewicz
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Joe S Mymryk
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada; Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada; Department of Oncology, The University of Western Ontario, London, ON, Canada; London Regional Cancer Program, Lawson Health Research Institute, London, ON, Canada.
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ARHGEF26 enhances Salmonella invasion and inflammation in cells and mice. PLoS Pathog 2021; 17:e1009713. [PMID: 34242364 PMCID: PMC8294491 DOI: 10.1371/journal.ppat.1009713] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 07/21/2021] [Accepted: 06/14/2021] [Indexed: 11/25/2022] Open
Abstract
Salmonella hijack host machinery in order to invade cells and establish infection. While considerable work has described the role of host proteins in invasion, much less is known regarding how natural variation in these invasion-associated host proteins affects Salmonella pathogenesis. Here we leveraged a candidate cellular GWAS screen to identify natural genetic variation in the ARHGEF26 (Rho Guanine Nucleotide Exchange Factor 26) gene that renders lymphoblastoid cells susceptible to Salmonella Typhi and Typhimurium invasion. Experimental follow-up redefined ARHGEF26’s role in Salmonella epithelial cell infection. Specifically, we identified complex serovar-by-host interactions whereby ARHGEF26 stimulation of S. Typhi and S. Typhimurium invasion into host cells varied in magnitude and effector-dependence based on host cell type. While ARHGEF26 regulated SopB- and SopE-mediated S. Typhi (but not S. Typhimurium) infection of HeLa cells, the largest effect of ARHGEF26 was observed with S. Typhimurium in polarized MDCK cells through a SopB- and SopE2-independent mechanism. In both cell types, knockdown of the ARHGEF26-associated protein DLG1 resulted in a similar phenotype and serovar specificity. Importantly, we show that ARHGEF26 plays a critical role in S. Typhimurium pathogenesis by contributing to bacterial burden in the enteric fever murine model, as well as inflammation in the colitis infection model. In the enteric fever model, SopB and SopE2 are required for the effects of Arhgef26 deletion on bacterial burden, and the impact of sopB and sopE2 deletion in turn required ARHGEF26. In contrast, SopB and SopE2 were not required for the impacts of Arhgef26 deletion on colitis. A role for ARHGEF26 on inflammation was also seen in cells, as knockdown reduced IL-8 production in HeLa cells. Together, these data reveal pleiotropic roles for ARHGEF26 during infection and highlight that many of the interactions that occur during infection that are thought to be well understood likely have underappreciated complexity. During infection, Salmonella manipulates host cells into engulfing the bacteria and establishing an intracellular niche. While many studies have identified genes involved in different stages of this Salmonella invasion process, few studies have examined how differences between human hosts contribute to infection susceptibility. Here we leveraged a candidate genetic screen to identify natural genetic variation in the human ARHGEF26 gene that correlates with Salmonella invasion. Springboarding from this result, we experimentally tested and redefined ARHGEF26’s role in Salmonella invasion, discovered a new role for ARHGEF26 in regulating inflammation during Salmonella disease, and demonstrated the relevance of these findings in mouse models. Building on how ARHGEF26 functions in other contexts, we implicated two ARHGEF26-interacting host proteins as contributors to Salmonella pathobiology. Collectively, these results identify a potential source of inter-person diversity in susceptibility to Salmonella disease and expand our molecular understanding of Salmonella infection to include a multifaceted role for ARHGEF26. They further identify important future directions in understanding how Salmonella recruit and manipulate ARHGEF26 as well as how ARHGEF26 is able to drive Salmonella-beneficial processes.
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Double inhibition and activation mechanisms of Ephexin family RhoGEFs. Proc Natl Acad Sci U S A 2021; 118:2024465118. [PMID: 33597305 DOI: 10.1073/pnas.2024465118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ephexin family guanine nucleotide exchange factors (GEFs) transfer signals from Eph tyrosine kinase receptors to Rho GTPases, which play critical roles in diverse cellular processes, as well as cancers and brain disorders. Here, we elucidate the molecular basis underlying inhibition and activation of Ephexin family RhoGEFs. The crystal structures of partially and fully autoinhibited Ephexin4 reveal that the complete autoinhibition requires both N- and C-terminal inhibitory modes, which can operate independently to impede Ras homolog family member G (RhoG) access. This double inhibition mechanism is commonly employed by other Ephexins and SGEF, another RhoGEF for RhoG. Structural, enzymatic, and cell biological analyses show that phosphorylation of a conserved tyrosine residue in its N-terminal inhibitory domain and association of PDZ proteins with its C-terminal PDZ-binding motif may respectively relieve the two autoinhibitory modes in Ephexin4. Our study provides a mechanistic framework for understanding the fine-tuning regulation of Ephexin4 GEF activity and offers possible clues for its pathological dysfunction.
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Rho GTPases in Gynecologic Cancers: In-Depth Analysis toward the Paradigm Change from Reactive to Predictive, Preventive, and Personalized Medical Approach Benefiting the Patient and Healthcare. Cancers (Basel) 2020; 12:cancers12051292. [PMID: 32443784 PMCID: PMC7281750 DOI: 10.3390/cancers12051292] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/12/2020] [Accepted: 05/13/2020] [Indexed: 12/24/2022] Open
Abstract
Rho guanosine triphospatases (GTPases) resemble a conserved family of GTP-binding proteins regulating actin cytoskeleton dynamics and several signaling pathways central for the cell. Rho GTPases create a so-called Ras-superfamily of GTPases subdivided into subgroups comprising at least 20 members. Rho GTPases play a key regulatory role in gene expression, cell cycle control and proliferation, epithelial cell polarity, cell migration, survival, and apoptosis, among others. They also have tissue-related functions including angiogenesis being involved in inflammatory and wound healing processes. Contextually, any abnormality in the Rho GTPase function may result in severe consequences at molecular, cellular, and tissue levels. Rho GTPases also play a key role in tumorigenesis and metastatic disease. Corresponding mechanisms include a number of targets such as kinases and scaffold/adaptor-like proteins initiating GTPases-related signaling cascades. The accumulated evidence demonstrates the oncogenic relevance of Rho GTPases for several solid malignancies including breast, liver, bladder, melanoma, testicular, lung, central nervous system (CNS), head and neck, cervical, and ovarian cancers. Furthermore, Rho GTPases play a crucial role in the development of radio- and chemoresistance e.g. under cisplatin-based cancer treatment. This article provides an in-depth overview on the role of Rho GTPases in gynecological cancers, highlights relevant signaling pathways and pathomechanisms, and sheds light on their involvement in tumor progression, metastatic spread, and radio/chemo resistance. In addition, insights into a spectrum of novel biomarkers and innovative approaches based on the paradigm shift from reactive to predictive, preventive, and personalized medicine are provided.
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8
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Dizanzo MP, Marziali F, Brunet Avalos C, Bugnon Valdano M, Leiva S, Cavatorta AL, Gardiol D. HPV E6 and E7 oncoproteins cooperatively alter the expression of Disc Large 1 polarity protein in epithelial cells. BMC Cancer 2020; 20:293. [PMID: 32264889 PMCID: PMC7137215 DOI: 10.1186/s12885-020-06778-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 03/23/2020] [Indexed: 11/30/2022] Open
Abstract
Background Persistent infection with high-risk Human Papillomavirus (HPVs) is associated with the development of cervical cancer. The transforming capacity of these viruses relies on the cooperative action of the E6 and E7 viral oncoproteins. Among the oncogenic activities of E6, the interaction and interference with cell polarity PDZ proteins have been well established. One of the most characterized PDZ targets of HPV E6 is human Disc large 1 (DLG1), a scaffolding protein involved in the control of cell polarity and proliferation. Interestingly, in cervical squamous intraepithelial lesions, alterations in DLG1 expression were observed in association to tumour progression. Moreover, the expression of both HPV E6 and E7 proteins may be responsible for the changes in DLG1 abundance and cell localization observed in the HPV-associated lesions. Methods Due to the relevance of DLG1 deregulation in tumour development, we have performed an in-depth investigation of the expression of DLG1 in the presence of the HPV oncoproteins in epithelial cultured cells. The effects of HPV E6 and E7 proteins on DLG1 abundance and subcellular localization were assessed by western blot and confocal fluorescence microscopy, respectively. Results We demonstrated that the relative abundance of HPV-18 E6 and DLG1 is a key factor that contributes to defining the expression abundance of both proteins. We also show here that a high expression level of DLG1 may negatively affect HPV-18 E6 nuclear expression. Moreover, the co-expression of HPV-18 E6 and E7 produces a striking effect on DLG1 subcellular localization and a co-distribution in the cytoplasmic region. Interestingly, HPV-18 E7 is also able to increase DLG1 levels, likely by rescuing it from the E6-mediated proteasomal degradation. Conclusions In general, the data suggest that HPV-18 E6 and E7 may have opposing activities in regards to the regulation of DLG1 levels and may cooperatively contribute to its subcellular redistribution in the HPV context. These findings constitute a step forward in understanding the differential expression of DLG1 during tumour progression in an HPV-associated model.
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Affiliation(s)
- María Paula Dizanzo
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Federico Marziali
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Clarisse Brunet Avalos
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Marina Bugnon Valdano
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Santiago Leiva
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Ana Laura Cavatorta
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Daniela Gardiol
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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Valgardson J, Cosbey R, Houser P, Rupp M, Van Bronkhorst R, Lee M, Jagodzinski F, Amacher JF. MotifAnalyzer-PDZ: A computational program to investigate the evolution of PDZ-binding target specificity. Protein Sci 2019; 28:2127-2143. [PMID: 31599029 DOI: 10.1002/pro.3741] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 12/15/2022]
Abstract
Recognition of short linear motifs (SLiMs) or peptides by proteins is an important component of many cellular processes. However, due to limited and degenerate binding motifs, prediction of cellular targets is challenging. In addition, many of these interactions are transient and of relatively low affinity. Here, we focus on one of the largest families of SLiM-binding domains in the human proteome, the PDZ domain. These domains bind the extreme C-terminus of target proteins, and are involved in many signaling and trafficking pathways. To predict endogenous targets of PDZ domains, we developed MotifAnalyzer-PDZ, a program that filters and compares all motif-satisfying sequences in any publicly available proteome. This approach enables us to determine possible PDZ binding targets in humans and other organisms. Using this program, we predicted and biochemically tested novel human PDZ targets by looking for strong sequence conservation in evolution. We also identified three C-terminal sequences in choanoflagellates that bind a choanoflagellate PDZ domain, the Monsiga brevicollis SHANK1 PDZ domain (mbSHANK1), with endogenously-relevant affinities, despite a lack of conservation with the targets of a homologous human PDZ domain, SHANK1. All three are predicted to be signaling proteins, with strong sequence homology to cytosolic and receptor tyrosine kinases. Finally, we analyzed and compared the positional amino acid enrichments in PDZ motif-satisfying sequences from over a dozen organisms. Overall, MotifAnalyzer-PDZ is a versatile program to investigate potential PDZ interactions. This proof-of-concept work is poised to enable similar types of analyses for other SLiM-binding domains (e.g., MotifAnalyzer-Kinase). MotifAnalyzer-PDZ is available at http://motifAnalyzerPDZ.cs.wwu.edu.
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Affiliation(s)
- Jordan Valgardson
- Department of Computer Science, Western Washington University, Bellingham, Washington.,Department of Chemistry, Western Washington University, Bellingham, Washington
| | - Robin Cosbey
- Department of Computer Science, Western Washington University, Bellingham, Washington
| | - Paul Houser
- Department of Computer Science, Western Washington University, Bellingham, Washington
| | - Milo Rupp
- Department of Computer Science, Western Washington University, Bellingham, Washington
| | - Raiden Van Bronkhorst
- Department of Computer Science, Western Washington University, Bellingham, Washington
| | - Michael Lee
- Department of Computer Science, Western Washington University, Bellingham, Washington
| | - Filip Jagodzinski
- Department of Computer Science, Western Washington University, Bellingham, Washington
| | - Jeanine F Amacher
- Department of Chemistry, Western Washington University, Bellingham, Washington
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Awadia S, Huq F, Arnold TR, Goicoechea SM, Sun YJ, Hou T, Kreider-Letterman G, Massimi P, Banks L, Fuentes EJ, Miller AL, Garcia-Mata R. SGEF forms a complex with Scribble and Dlg1 and regulates epithelial junctions and contractility. J Cell Biol 2019; 218:2699-2725. [PMID: 31248911 PMCID: PMC6683736 DOI: 10.1083/jcb.201811114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/18/2019] [Accepted: 04/12/2019] [Indexed: 01/15/2023] Open
Abstract
The canonical Scribble polarity complex is implicated in regulation of epithelial junctions and apical polarity. Here, we show that SGEF, a RhoG-specific GEF, forms a ternary complex with Scribble and Dlg1, two members of the Scribble complex. SGEF targets to apical junctions in a Scribble-dependent fashion and functions in the regulation of actomyosin-based contractility and barrier function at tight junctions as well as E-cadherin-mediated formation of adherens junctions. Surprisingly, SGEF does not control the establishment of polarity. However, in 3D cysts, SGEF regulates the formation of a single open lumen. Interestingly, SGEF's nucleotide exchange activity regulates the formation and maintenance of adherens junctions, and in cysts the number of lumens formed, whereas SGEF's scaffolding activity is critical for regulation of actomyosin contractility and lumen opening. We propose that SGEF plays a key role in coordinating junctional assembly and actomyosin contractility by bringing together Scribble and Dlg1 and targeting RhoG activation to cell-cell junctions.
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Affiliation(s)
- Sahezeel Awadia
- Department of Biological Sciences, The University of Toledo, Toledo, OH
| | - Farah Huq
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Torey R Arnold
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | | | - Young Joo Sun
- Department of Biochemistry, University of Iowa, Iowa City, IA
| | - Titus Hou
- Department of Biochemistry, University of Iowa, Iowa City, IA
| | | | - Paola Massimi
- International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Lawrence Banks
- International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | | | - Ann L Miller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
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Webb Strickland S, Brimer N, Lyons C, Vande Pol SB. Human Papillomavirus E6 interaction with cellular PDZ domain proteins modulates YAP nuclear localization. Virology 2018; 516:127-138. [PMID: 29346075 DOI: 10.1016/j.virol.2018.01.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 12/19/2017] [Accepted: 01/02/2018] [Indexed: 01/28/2023]
Abstract
HPV E6 oncoproteins associate with cellular PDZ proteins. In addition to previously identified cellular PDZ proteins, we found association of the HPV16 E6 PBM with the Dystrophin Glycoprotein Complex, LRCC1, and SLC9A3R2. HPV18 E6 had additional associations when lysates from adenomatous cell lines were used including LRPPRC, RLGAPB, EIF3A, SMC2 and 3, AMOT, AMOTL1, and ARHGEF1; some of these cellular PDZ proteins are implicated in the regulation of the YAP1 transcriptional co-activator. In keratinocytes, nuclear translocation of YAP1 was promoted by the complete HPV-16 genome, or by expression of the individual E6 or E7 oncoproteins; the activity of E6 required an intact PBM at the carboxy-terminus. This work demonstrates that E6 association with cellular PDZ proteins promotes the nuclear localization of YAP1. The ability of E6 to promote the nuclear transport of YAP1 thus identifies an E6 activity that could contribute to the transformation of cells by E6.
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Affiliation(s)
- Sydney Webb Strickland
- Department of Pathology, University of Virginia, Charlottesville, VA 22901, United States
| | - Nicole Brimer
- Department of Pathology, University of Virginia, Charlottesville, VA 22901, United States
| | - Charles Lyons
- Department of Pathology, University of Virginia, Charlottesville, VA 22901, United States
| | - Scott B Vande Pol
- Department of Pathology, University of Virginia, Charlottesville, VA 22901, United States.
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12
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Marziali F, Bugnon Valdano M, Brunet Avalos C, Moriena L, Cavatorta AL, Gardiol D. Interference of HTLV-1 Tax Protein with Cell Polarity Regulators: Defining the Subcellular Localization of the Tax-DLG1 Interaction. Viruses 2017; 9:E355. [PMID: 29168728 PMCID: PMC5744130 DOI: 10.3390/v9120355] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 11/15/2017] [Accepted: 11/21/2017] [Indexed: 12/17/2022] Open
Abstract
Human T cell leukemia virus (HTLV)-1 Tax (Tax) protein is very important in viral replication and cell transformation. Tax localizes in the nucleus and cytoplasm in association with organelles. Some activities of Tax depend on interactions with PDZ (PSD-95/Discs Large/Z0-1) domain-containing proteins such as Discs large protein 1 (DLG1) which is involved in cell polarity and proliferation. The DLG1 interaction results in a cytoplasmic co-localization pattern resembling vesicular aggregates, the nature of which is still unknown. To further explore the role of PDZ proteins in HTLV-1 cell transformation, we deeply investigated the Tax-DLG1 association. By fluorescence resonance energy transfer (FRET), we detected, for the first time, the direct binding of Tax to DLG1 within the cell. We showed that the interaction specifically affects the cellular distribution of not only DLG1, but also Tax. After studying different cell structures, we demonstrated that the aggregates distribute into the Golgi apparatus in spatial association with the microtubule-organizing center (MTOC). This study contributes to understand the biological significance of Tax-PDZ interactions.
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Affiliation(s)
- Federico Marziali
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
| | - Marina Bugnon Valdano
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
| | - Clarisse Brunet Avalos
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
| | - Lucía Moriena
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
| | - Ana Laura Cavatorta
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
| | - Daniela Gardiol
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
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13
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Valdivia A, Goicoechea SM, Awadia S, Zinn A, Garcia-Mata R. Regulation of circular dorsal ruffles, macropinocytosis, and cell migration by RhoG and its exchange factor, Trio. Mol Biol Cell 2017; 28:1768-1781. [PMID: 28468978 PMCID: PMC5491185 DOI: 10.1091/mbc.e16-06-0412] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 04/20/2017] [Accepted: 04/25/2017] [Indexed: 11/11/2022] Open
Abstract
The small GTPase RhoG and its exchange factor, Trio, regulate the formation and size of circular dorsal ruffles and associated functions, including macropinocytosis and cell migration. Circular dorsal ruffles (CDRs) are actin-rich structures that form on the dorsal surface of many mammalian cells in response to growth factor stimulation. CDRs represent a unique type of structure that forms transiently and only once upon stimulation. The formation of CDRs involves a drastic rearrangement of the cytoskeleton, which is regulated by the Rho family of GTPases. So far, only Rac1 has been consistently associated with CDR formation, whereas the role of other GTPases in this process is either lacking or inconclusive. Here we show that RhoG and its exchange factor, Trio, play a role in the regulation of CDR dynamics, particularly by modulating their size. RhoG is activated by Trio downstream of PDGF in a PI3K- and Src-dependent manner. Silencing RhoG expression decreases the number of cells that form CDRs, as well as the area of the CDRs. The regulation of CDR area by RhoG is independent of Rac1 function. In addition, our results show the RhoG plays a role in the cellular functions associated with CDR formation, including macropinocytosis, receptor internalization, and cell migration. Taken together, our results reveal a novel role for RhoG in the regulation of CDRs and the cellular processes associated with their formation.
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Affiliation(s)
- Alejandra Valdivia
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606.,Division of Cardiology, School of Medicine, Emory University, Atlanta, GA 30322
| | | | - Sahezeel Awadia
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Ashtyn Zinn
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Rafael Garcia-Mata
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
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14
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Goicoechea SM, Zinn A, Awadia SS, Snyder K, Garcia-Mata R. A RhoG-mediated signaling pathway that modulates invadopodia dynamics in breast cancer cells. J Cell Sci 2017; 130:1064-1077. [PMID: 28202690 DOI: 10.1242/jcs.195552] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 01/14/2017] [Indexed: 01/11/2023] Open
Abstract
One of the hallmarks of cancer is the ability of tumor cells to invade surrounding tissues and metastasize. During metastasis, cancer cells degrade the extracellular matrix, which acts as a physical barrier, by developing specialized actin-rich membrane protrusion structures called invadopodia. The formation of invadopodia is regulated by Rho GTPases, a family of proteins that regulates the actin cytoskeleton. Here, we describe a novel role for RhoG in the regulation of invadopodia disassembly in human breast cancer cells. Our results show that RhoG and Rac1 have independent and opposite roles in the regulation of invadopodia dynamics. We also show that SGEF (also known as ARHGEF26) is the exchange factor responsible for the activation of RhoG during invadopodia disassembly. When the expression of either RhoG or SGEF is silenced, invadopodia are more stable and have a longer lifetime than in control cells. Our findings also demonstrate that RhoG and SGEF modulate the phosphorylation of paxillin, which plays a key role during invadopodia disassembly. In summary, we have identified a novel signaling pathway involving SGEF, RhoG and paxillin phosphorylation, which functions in the regulation of invadopodia disassembly in breast cancer cells.
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Affiliation(s)
- Silvia M Goicoechea
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
| | - Ashtyn Zinn
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
| | - Sahezeel S Awadia
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
| | - Kyle Snyder
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
| | - Rafael Garcia-Mata
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
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15
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Cavatorta AL, Di Gregorio A, Bugnon Valdano M, Marziali F, Cabral M, Bottai H, Cittadini J, Nocito AL, Gardiol D. DLG1 polarity protein expression associates with the disease progress of low-grade cervical intraepithelial lesions. Exp Mol Pathol 2016; 102:65-69. [PMID: 28040505 DOI: 10.1016/j.yexmp.2016.12.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 11/22/2016] [Accepted: 12/19/2016] [Indexed: 12/31/2022]
Abstract
Human Discs large tumour suppressor (DLG1) participates in regulating cell polarity and proliferation, suggesting an important connection between epithelial organization and cellular growth control. However, it was demonstrated that DLG1 could acquire oncogenic attributes in some specific contexts. In this work, we evaluated the expression of DLG1 and its contribution to the progress of cervical lesions in order to investigate a potential role of this polarity protein in human oncogenic processes. We analyzed cervical biopsies from women with low-grade squamous intraepithelial lesion (LSIL) diagnosis (n=30), for DLG1 expression by immunohistochemistry. These results were correlated with the clinical monitoring of the patients during a 24-month follow-up period. Our data indicate that while all LSIL patients with a DLG1 staining pattern similar to normal tissues are significantly more likely to regress (n=23, Pattern I), all LSIL biopsy specimens showing a diffuse and intense DLG1 staining likely progress to high-grade lesions (n=4, Pattern II). Finally, all persistent LSIL analyzed showed an undetermined DLG1 staining, with a diffuse distribution without a strong intensity (n=3, Pattern III). We found a significant association between the expression pattern of DLG1 and the evolution of the lesion (p<0.00001). This work contributes to the knowledge of DLG1 biological functions, suggesting that its expression may have an important role in the progression of early dysplastic cervical lesions, giving prognostic information.
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Affiliation(s)
- Ana Laura Cavatorta
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | | | - Marina Bugnon Valdano
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | - Federico Marziali
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | - Mariela Cabral
- Servicio de Ginecología, Hospital Provincial del Centenario, Rosario, Argentina
| | - Hebe Bottai
- Área Estadística y Procesamiento de Datos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Argentina
| | - Jorge Cittadini
- Servicio de Ginecología, Hospital Provincial del Centenario, Rosario, Argentina
| | - Ana Lia Nocito
- Cátedra de Anatomía y Fisiología Patológicas, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Daniela Gardiol
- Instituto de Biología Molecular y Celular de Rosario-CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina.
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16
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The high-risk HPV E6 target scribble (hScrib) is required for HPV E6 expression in cervical tumour-derived cell lines. PAPILLOMAVIRUS RESEARCH 2016; 2:70-77. [PMID: 29074188 PMCID: PMC5886876 DOI: 10.1016/j.pvr.2016.04.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 03/08/2016] [Accepted: 04/05/2016] [Indexed: 11/21/2022]
Abstract
The ability of high-risk HPV E6 oncoproteins to target cellular proteins which harbor PDZ domains is believed to play an important role in the virus life cycle and to influence the ability of these viruses to bring about malignant transformation. Whilst many of these PDZ proteins are potential tumour suppressors, involved in the control of cell polarity and cell-contact, recent studies suggest that mislocalisation or overexpression might result in the emergence of oncogenic functions. This has been shown most clearly for two E6 targets, hDlg and hScrib. In this study we show that hScrib plays such a role in HeLa cells, where its expression is required for maintaining high levels of HPV-18 E6 protein. Loss of hScrib has no effect on E6 stability but results in lower levels of E6 transcription and a reduced rate of E6 translation. We further show that, in the context of cervical tumour-derived cell lines, both hScrib and E6 cooperate in the activation of the S6 kinase signaling pathway, and thereby contribute towards maintaining high rates of protein translation. These results indicate that the residual hScrib that is present within HPV transformed cells is pro-oncogenic, and highlights the dual functions of E6 cell polarity targets.
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17
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Valdano MB, Cavatorta AL, Morale MG, Marziali F, de Souza Lino V, Steenbergen RDM, Boccardo E, Gardiol D. Disc large 1 expression is altered by human papillomavirus E6/E7 proteins in organotypic cultures of human keratinocytes. J Gen Virol 2016; 97:453-462. [DOI: 10.1099/jgv.0.000364] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- M. Bugnon Valdano
- Instituto de Biología Molecular y Celular de Rosario – CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | - A. L. Cavatorta
- Instituto de Biología Molecular y Celular de Rosario – CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | - M. G. Morale
- Deparment of Biochemistry, Institute of Chemistry, University of Sao Paulo, Sao Paulo, Brazil
| | - F. Marziali
- Instituto de Biología Molecular y Celular de Rosario – CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | - V. de Souza Lino
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - R. D. M. Steenbergen
- Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands
| | - E. Boccardo
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - D. Gardiol
- Instituto de Biología Molecular y Celular de Rosario – CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
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18
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James CD, Roberts S. Viral Interactions with PDZ Domain-Containing Proteins-An Oncogenic Trait? Pathogens 2016; 5:pathogens5010008. [PMID: 26797638 PMCID: PMC4810129 DOI: 10.3390/pathogens5010008] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 01/14/2016] [Accepted: 01/15/2016] [Indexed: 02/06/2023] Open
Abstract
Many of the human viruses with oncogenic capabilities, either in their natural host or in experimental systems (hepatitis B and C, human T cell leukaemia virus type 1, Kaposi sarcoma herpesvirus, human immunodeficiency virus, high-risk human papillomaviruses and adenovirus type 9), encode in their limited genome the ability to target cellular proteins containing PSD95/ DLG/ZO-1 (PDZ) interaction modules. In many cases (but not always), the viruses have evolved to bind the PDZ domains using the same short linear peptide motifs found in host protein-PDZ interactions, and in some cases regulate the interactions in a similar fashion by phosphorylation. What is striking is that the diverse viruses target a common subset of PDZ proteins that are intimately involved in controlling cell polarity and the structure and function of intercellular junctions, including tight junctions. Cell polarity is fundamental to the control of cell proliferation and cell survival and disruption of polarity and the signal transduction pathways involved is a key event in tumourigenesis. This review focuses on the oncogenic viruses and the role of targeting PDZ proteins in the virus life cycle and the contribution of virus-PDZ protein interactions to virus-mediated oncogenesis. We highlight how many of the viral associations with PDZ proteins lead to deregulation of PI3K/AKT signalling, benefitting virus replication but as a consequence also contributing to oncogenesis.
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Affiliation(s)
- Claire D James
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Vincent Drive, Birmingham B15 2TT, UK.
- Present address; Virginia Commonwealth University, School of Dentistry, W. Baxter Perkinson Jr. Building, 521 North 11th Street, P.O. Box 980566, Richmond, VA 23298-0566, USA.
| | - Sally Roberts
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Vincent Drive, Birmingham B15 2TT, UK.
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19
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Ensign SPF, Roos A, Mathews IT, Dhruv HD, Tuncali S, Sarkaria JN, Symons MH, Loftus JC, Berens ME, Tran NL. SGEF Is Regulated via TWEAK/Fn14/NF-κB Signaling and Promotes Survival by Modulation of the DNA Repair Response to Temozolomide. Mol Cancer Res 2016; 14:302-12. [PMID: 26764186 DOI: 10.1158/1541-7786.mcr-15-0183] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 12/09/2015] [Indexed: 12/11/2022]
Abstract
UNLABELLED Glioblastoma (GB) is the highest grade and most common form of primary adult brain tumors. Despite surgical removal followed by concomitant radiation and chemotherapy with the alkylating agent temozolomide, GB tumors develop treatment resistance and ultimately recur. Impaired response to treatment occurs rapidly, conferring a median survival of just fifteen months. Thus, it is necessary to identify the genetic and signaling mechanisms that promote tumor resistance to develop targeted therapies to combat this refractory disease. Previous observations indicated that SGEF (ARHGEF26), a RhoG-specific guanine nucleotide exchange factor (GEF), is overexpressed in GB tumors and plays a role in promoting TWEAK-Fn14-mediated glioma invasion. Here, further investigation revealed an important role for SGEF in glioma cell survival. SGEF expression is upregulated by TWEAK-Fn14 signaling via NF-κB activity while shRNA-mediated reduction of SGEF expression sensitizes glioma cells to temozolomide-induced apoptosis and suppresses colony formation following temozolomide treatment. Nuclear SGEF is activated following temozolomide exposure and complexes with the DNA damage repair (DDR) protein BRCA1. Moreover, BRCA1 phosphorylation in response to temozolomide treatment is hindered by SGEF knockdown. The role of SGEF in promoting chemotherapeutic resistance highlights a heretofore unappreciated driver, and suggests its candidacy for development of novel targeted therapeutics for temozolomide-refractory, invasive GB cells. IMPLICATION SGEF, as a dual process modulator of cell survival and invasion, represents a novel target for treatment refractory glioblastoma.
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Affiliation(s)
- Shannon P Fortin Ensign
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona. Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, Arizona
| | - Alison Roos
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona
| | - Ian T Mathews
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona
| | - Harshil D Dhruv
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona
| | - Serdar Tuncali
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona
| | - Jann N Sarkaria
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | - Marc H Symons
- Center for Oncology and Cell Biology, The Feinstein Institute for Medical Research at North Shore-LIJ, Manhasset, New York
| | - Joseph C Loftus
- Department of Biochemistry and Molecular Biology, Mayo Clinic Arizona, Scottsdale, Arizona
| | - Michael E Berens
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona
| | - Nhan L Tran
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona.
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20
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E3 ligase EDD1/UBR5 is utilized by the HPV E6 oncogene to destabilize tumor suppressor TIP60. Oncogene 2015; 35:2062-74. [DOI: 10.1038/onc.2015.268] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 05/04/2015] [Accepted: 06/07/2015] [Indexed: 02/08/2023]
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21
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Ganti K, Broniarczyk J, Manoubi W, Massimi P, Mittal S, Pim D, Szalmas A, Thatte J, Thomas M, Tomaić V, Banks L. The Human Papillomavirus E6 PDZ Binding Motif: From Life Cycle to Malignancy. Viruses 2015; 7:3530-51. [PMID: 26147797 PMCID: PMC4517114 DOI: 10.3390/v7072785] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 06/24/2015] [Accepted: 06/25/2015] [Indexed: 01/01/2023] Open
Abstract
Cancer-causing HPV E6 oncoproteins are characterized by the presence of a PDZ binding motif (PBM) at their extreme carboxy terminus. It was long thought that this region of E6 had a sole function to confer interaction with a defined set of cellular substrates. However, more recent studies have shown that the E6 PBM has a complex pattern of regulation, whereby phosphorylation within the PBM can regulate interaction with two classes of cellular proteins: those containing PDZ domains and the members of the 14-3-3 family of proteins. In this review, we explore the roles that the PBM and its ligands play in the virus life cycle, and subsequently how these can inadvertently contribute towards the development of malignancy. We also explore how subtle alterations in cellular signal transduction pathways might result in aberrant E6 phosphorylation, which in turn might contribute towards disease progression.
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Affiliation(s)
- Ketaki Ganti
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Justyna Broniarczyk
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Wiem Manoubi
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Paola Massimi
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Suruchi Mittal
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - David Pim
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Anita Szalmas
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Jayashree Thatte
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Miranda Thomas
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Vjekoslav Tomaić
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
| | - Lawrence Banks
- International Center for Genetic Engineering and Biotechnology, Area Science Park, Padriciano 99, Trieste 34149, Italy.
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22
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The human adenovirus E4-ORF1 protein subverts discs large 1 to mediate membrane recruitment and dysregulation of phosphatidylinositol 3-kinase. PLoS Pathog 2014; 10:e1004102. [PMID: 24788832 PMCID: PMC4006922 DOI: 10.1371/journal.ppat.1004102] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 03/18/2014] [Indexed: 12/19/2022] Open
Abstract
Adenoviruses infect epithelial cells lining mucous membranes to cause acute diseases in people. They are also utilized as vectors for vaccination and for gene and cancer therapy, as well as tools to discover mechanisms of cancer due to their tumorigenic potential in experimental animals. The adenovirus E4-ORF1 gene encodes an oncoprotein that promotes viral replication, cell survival, and transformation by activating phosphatidylinositol 3-kinase (PI3K). While the mechanism of activation is not understood, this function depends on a complex formed between E4-ORF1 and the membrane-associated cellular PDZ protein Discs Large 1 (Dlg1), a common viral target having both tumor suppressor and oncogenic functions. Here, we report that in human epithelial cells, E4-ORF1 interacts with the regulatory and catalytic subunits of PI3K and elevates their levels. Like PI3K activation, PI3K protein elevation by E4-ORF1 requires Dlg1. We further show that Dlg1, E4-ORF1, and PI3K form a ternary complex at the plasma membrane. At this site, Dlg1 also co-localizes with the activated PI3K effector protein Akt, indicating that the ternary complex mediates PI3K signaling. Signifying the functional importance of the ternary complex, the capacity of E4-ORF1 to induce soft agar growth and focus formation in cells is ablated either by a mutation that prevents E4-ORF1 binding to Dlg1 or by a PI3K inhibitor drug. These results demonstrate that E4-ORF1 interacts with Dlg1 and PI3K to assemble a ternary complex where E4-ORF1 hijacks the Dlg1 oncogenic function to relocate cytoplasmic PI3K to the membrane for constitutive activation. This novel mechanism of Dlg1 subversion by adenovirus to dysregulate PI3K could be used by other pathogenic viruses, such as human papillomavirus, human T-cell leukemia virus type 1, and influenza A virus, which also target Dlg1 and activate PI3K in cells. Adenoviruses cause acute illnesses in people, and are additionally utilized both as vehicles to cure genetic diseases, fight cancer, and deliver vaccines, and as tools to discover how cancers develop due to a capacity to generate tumors in experimental animals. The adenovirus E4-ORF1 protein reprograms cell metabolism to enhance virus production in infected cells and promotes cell survival and tumors by activating the important cellular protein phosphatidylinositol 3-kinase (PI3K). How E4-ORF1 activates PI3K is not known, though this function depends on E4-ORF1 binding to the membrane-associated cellular protein Discs Large 1 (Dlg1), which many different viruses evolved to target. In this study, we identify PI3K as a new direct target of E4-ORF1. Results further show that E4-ORF1 binds to PI3K in the cytoplasm and delivers it to Dlg1 at the membrane where the three proteins form a complex that activates PI3K and induces oncogenic growth in cells. This novel molecular mechanism in which adenovirus subverts Dlg1 to dysregulate PI3K may serve as a paradigm to understand PI3K activation mediated by other important pathogenic viruses, such as human papillomavirus, human T-cell leukemia virus type 1, and influenza A virus, which also target Dlg1 in infected cells.
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23
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Wang H, Li S, Li H, Wang P, Huang F, Zhao Y, Yu L, Luo G, Zhang X, Wang J, Zhou J. Grb2 interacts with SGEF and antagonizes the ability of SGEF to enhance EGF-induced ERK1/2 activation. Mol Cell Biochem 2014; 389:239-47. [PMID: 24399467 DOI: 10.1007/s11010-013-1945-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 12/18/2013] [Indexed: 02/02/2023]
Abstract
Previously, we demonstrated that SGEF enhances EGFR stability; however, SGEF-mediated downstream signaling of EGFR is not well understood. Here, we show that SGEF enhances EGF-induced ERK1/2 activation independent of its guanine nucleotide exchange (GEF) activity. We further show that SGEF interacts with Grb2, a critical downstream transducer of EGFR. Surprisingly, we found that interaction of Grb2 to SGEF antagonizes the ability of SGEF to enhance EGF-induced ERK1/2 activation. Taken together, this study reports a novel function of SGEF that excludes GEF and also provides important insights into the complex role of Grb2 in EGFR signal transduction.
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Affiliation(s)
- Hongtao Wang
- Laboratory of Medical Molecular Biology, Beijing Institute of Biotechnology, 27 Taiping Road, Haidian, Beijing, 100850, People's Republic of China
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Fortin Ensign SP, Mathews IT, Symons MH, Berens ME, Tran NL. Implications of Rho GTPase Signaling in Glioma Cell Invasion and Tumor Progression. Front Oncol 2013; 3:241. [PMID: 24109588 PMCID: PMC3790103 DOI: 10.3389/fonc.2013.00241] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 09/02/2013] [Indexed: 01/21/2023] Open
Abstract
Glioblastoma (GB) is the most malignant of primary adult brain tumors, characterized by a highly locally invasive cell population, as well as abundant proliferative cells, neoangiogenesis, and necrosis. Clinical intervention with chemotherapy or radiation may either promote or establish an environment for manifestation of invasive behavior. Understanding the molecular drivers of invasion in the context of glioma progression may be insightful in directing new treatments for patients with GB. Here, we review current knowledge on Rho family GTPases, their aberrant regulation in GB, and their effect on GB cell invasion and tumor progression. Rho GTPases are modulators of cell migration through effects on actin cytoskeleton rearrangement; in non-neoplastic tissue, expression and activation of Rho GTPases are normally under tight regulation. In GB, Rho GTPases are deregulated, often via hyperactivity or overexpression of their activators, Rho GEFs. Downstream effectors of Rho GTPases have been shown to promote invasiveness and, importantly, glioma cell survival. The study of aberrant Rho GTPase signaling in GB is thus an important investigation of cell invasion as well as treatment resistance and disease progression.
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Affiliation(s)
- Shannon Patricia Fortin Ensign
- Cancer and Cell Biology Division, Translational Genomics Research Institute , Phoenix, AZ , USA ; Cancer Biology Graduate Interdisciplinary Program, University of Arizona , Tucson, AZ , USA
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25
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PDZ domains and viral infection: versatile potentials of HPV-PDZ interactions in relation to malignancy. BIOMED RESEARCH INTERNATIONAL 2013; 2013:369712. [PMID: 24093094 PMCID: PMC3777178 DOI: 10.1155/2013/369712] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/09/2013] [Accepted: 07/31/2013] [Indexed: 12/13/2022]
Abstract
Cervical cancer is caused by high-risk human papillomaviruses (HPVs), and a unique characteristic of these is a PDZ (P¯SD-95/D¯lg/Z¯O-1-)binding motif in their E6 proteins. Through this motif HPV E6 interacts with a variety of PDZ domain-containing proteins and targets them mainly for degradation. These E6-PDZ interactions exhibit extraordinarily different functions in relation to HPV-induced malignancy, depending upon various cellular contexts; for example, Dlg and Scrib show different distribution patterns from what is seen in normal epithelium, both in localization and in amount, and their loss may be a late-stage marker in malignant progression. Recent studies show that interactions with specific forms of the proteins may have oncogenic potential. In addition, it is interesting that PDZ proteins make a contribution to the stabilization of E6 and viral episomal maintenance during the course of HPV life cycle. Various posttranslational modifications also greatly affect their functions. Phosphorylation of hDlg and hScrib by certain kinases regulates several important signaling cascades, and E6-PDZ interactions themselves are regulated through PKA-dependent phosphorylation. Thus these interactions naturally have great potential for both predictive and therapeutic applications, and, with development of screening tools for identifying novel targets of their interactions, comprehensive spatiotemporal analysis is currently underway.
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26
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Wang H, Li S, Li H, Li C, Guan K, Luo G, Yu L, Wu R, Zhang X, Wang J, Zhou J. SGEF enhances EGFR stability through delayed EGFR trafficking from early to late endosomes. Carcinogenesis 2013; 34:1976-1983. [DOI: doi.org/10.1093/carcin/bgt157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2023] Open
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27
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Fortin Ensign SP, Mathews IT, Eschbacher JM, Loftus JC, Symons MH, Tran NL. The Src homology 3 domain-containing guanine nucleotide exchange factor is overexpressed in high-grade gliomas and promotes tumor necrosis factor-like weak inducer of apoptosis-fibroblast growth factor-inducible 14-induced cell migration and invasion via tumor necrosis factor receptor-associated factor 2. J Biol Chem 2013; 288:21887-97. [PMID: 23775076 DOI: 10.1074/jbc.m113.468686] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glioblastoma (GB) is the highest grade of primary adult brain tumors, characterized by a poorly defined and highly invasive cell population. Importantly, these invading cells are attributed with having a decreased sensitivity to radiation and chemotherapy. TNF-like weak inducer of apoptosis (TWEAK)-Fn14 ligand-receptor signaling is one mechanism in GB that promotes cell invasiveness and survival and is dependent upon the activity of multiple Rho GTPases, including Rac1. Here we report that Src homology 3 domain-containing guanine nucleotide exchange factor (SGEF), a RhoG-specific guanine nucleotide exchange factor, is overexpressed in GB tumors and promotes TWEAK-Fn14-mediated glioma invasion. Importantly, levels of SGEF expression in GB tumors inversely correlate with patient survival. SGEF mRNA expression is increased in GB cells at the invasive rim relative to those in the tumor core, and knockdown of SGEF expression by shRNA decreases glioma cell migration in vitro and invasion ex vivo. Furthermore, we showed that, upon TWEAK stimulation, SGEF is recruited to the Fn14 cytoplasmic tail via TRAF2. Mutation of the Fn14-TRAF domain site or depletion of TNF receptor-associated factor 2 (TRAF2) expression by siRNA oligonucleotides blocked SGEF recruitment to Fn14 and inhibited SGEF activity and subsequent GB cell migration. We also showed that knockdown of either SGEF or RhoG diminished TWEAK activation of Rac1 and subsequent lamellipodia formation. Together, these results indicate that SGEF-RhoG is an important downstream regulator of TWEAK-Fn14-driven GB cell migration and invasion.
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Affiliation(s)
- Shannon P Fortin Ensign
- Cancer and Cell Biology Division, The Translational Genomics Research Institute, Phoenix, Arizona 85004, USA
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28
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Vande Pol SB, Klingelhutz AJ. Papillomavirus E6 oncoproteins. Virology 2013; 445:115-37. [PMID: 23711382 DOI: 10.1016/j.virol.2013.04.026] [Citation(s) in RCA: 248] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 04/22/2013] [Accepted: 04/25/2013] [Indexed: 02/07/2023]
Abstract
Papillomaviruses induce benign and malignant epithelial tumors, and the viral E6 oncoprotein is essential for full transformation. E6 contributes to transformation by associating with cellular proteins, docking on specific acidic LXXLL peptide motifs found on these proteins. This review examines insights from recent studies of human and animal E6 proteins that determine the three-dimensional structure of E6 when bound to acidic LXXLL peptides. The structure of E6 is related to recent advances in the purification and identification of E6 associated protein complexes. These E6 protein-complexes, together with other proteins that bind to E6, alter a broad array of biological outcomes including modulation of cell survival, cellular transcription, host cell differentiation, growth factor dependence, DNA damage responses, and cell cycle progression.
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Affiliation(s)
- Scott B Vande Pol
- Department of Pathology, University of Virginia, Charlottesville, VA 22901, USA.
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29
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Wang H, Li S, Li H, Li C, Guan K, Luo G, Yu L, Wu R, Zhang X, Wang J, Zhou J. SGEF enhances EGFR stability through delayed EGFR trafficking from early to late endosomes. Carcinogenesis 2013; 34:1976-83. [PMID: 23661635 DOI: 10.1093/carcin/bgt157] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Previously, we demonstrated an elevated SH3-containing guanine nucleotide exchange factor (SGEF) expression in clinical specimens with prostate cancer and implicated the role of SGEF in prostate tumorigenesis. However, the molecular mechanism behind the SGEF regulation of prostate cancer development is not known. In this study, we show that SGEF expression delays epidermal growth factor receptor (EGFR) degradation in prostate cancer cells and is independent from its guanine nucleotide exchange factor (GEF) function. We further show that the delayed degradation is due to a delay in EGFR trafficking from early to late endosomes and not to a decrease in EGFR ubiquitination. Finally, we show that depletion of SGEF significantly inhibits epidermal growth factor-induced EGFR signaling cascade and cell migration in the prostate cancer cells. We report for the first time an SGEF function for RhoG that excludes GEF and the ability of SGEF to enhance EGFR stability and signaling by delaying its lysosomal sorting and degradation. This could be one mechanism by which SGEF contributes to prostate cancer progression.
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Affiliation(s)
- Hongtao Wang
- Laboratory of Medical Molecular Biology, Beijing Institute of Biotechnology, 27 Taiping Road, Haidian, Beijing 100850, China and
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30
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Mischo A, Ohlenschläger O, Hortschansky P, Ramachandran R, Görlach M. Structural insights into a wildtype domain of the oncoprotein E6 and its interaction with a PDZ domain. PLoS One 2013; 8:e62584. [PMID: 23638119 PMCID: PMC3640046 DOI: 10.1371/journal.pone.0062584] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 03/22/2013] [Indexed: 12/17/2022] Open
Abstract
The high-risk human papilloma virus (HPV) oncoproteins E6 and E7 interact with key cellular regulators and are etiological agents for tumorigenesis and tumor maintenance in cervical cancer and other malignant conditions. E6 induces degradation of the tumor suppressor p53, activates telomerase and deregulates cell polarity. Analysis of E6 derived from a number of high risk HPV finally yielded the first structure of a wild-type HPV E6 domain (PDB 2M3L) representing the second zinc-binding domain of HPV 51 E6 (termed 51Z2) determined by NMR spectroscopy. The 51Z2 structure provides clues about HPV-type specific structural differences between E6 proteins. The observed temperature sensitivity of the well-folded wild-type E6 domain implies a significant malleability of the oncoprotein in vivo. Hence, the structural differences between individual E6 and their malleability appear, together with HPV type-specific surface exposed side-chains, to provide the structural basis for the different interaction networks reported for individual E6 proteins. Furthermore, the interaction of 51Z2 with a PDZ domain of hDlg was analyzed. Human Dlg constitutes a prototypic representative of the large family of PDZ proteins regulating cell polarity, which are common targets of high-risk HPV E6. Nine C-terminal residues of 51Z2 interact with the second PDZ domain of hDlg2. Surface plasmon resonance in conjunction with the NMR spectroscopy derived complex structure (PDB 2M3M) indicate that E6 residues N-terminal to the canonical PDZ-BM of E6 significantly contribute to this interaction and increase affinity. The structure of the complex reveals how residues outside of the classical PDZ-BM enhance the affinity of E6 towards PDZ domains. Such mechanism facilitates successful competition of E6 with cellular PDZ-binding proteins and may apply to PDZ-binding proteins of other viruses as well.
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Affiliation(s)
- André Mischo
- Biomolecular NMR Spectroscopy, Leibniz Institute for Age Research - Fritz Lipmann Institute, Jena, Germany
| | - Oliver Ohlenschläger
- Biomolecular NMR Spectroscopy, Leibniz Institute for Age Research - Fritz Lipmann Institute, Jena, Germany
| | - Peter Hortschansky
- Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knöll-Institute, Jena, Germany
| | - Ramadurai Ramachandran
- Biomolecular NMR Spectroscopy, Leibniz Institute for Age Research - Fritz Lipmann Institute, Jena, Germany
| | - Matthias Görlach
- Biomolecular NMR Spectroscopy, Leibniz Institute for Age Research - Fritz Lipmann Institute, Jena, Germany
- * E-mail:
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Abstract
The role of cell polarity regulators in the development of cancer has long been an enigma. Despite displaying characteristics of tumour suppressors, the core regulators of polarity are rarely mutated in tumours and there are few data from animal models to suggest that they directly contribute to cancer susceptibility, thus questioning their relevance to human carcinogenesis. However, a body of data from human tumour viruses is now providing compelling evidence of a central role for the perturbation of cell polarity in the development of cancer.
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Affiliation(s)
- Lawrence Banks
- The International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34149 Trieste, Italy.
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32
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Roberts S, Delury C, Marsh E. The PDZ protein discs-large (DLG): the 'Jekyll and Hyde' of the epithelial polarity proteins. FEBS J 2012; 279:3549-3558. [PMID: 22846345 DOI: 10.1111/j.1742-4658.2012.08729.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 07/16/2012] [Accepted: 07/26/2012] [Indexed: 12/25/2022]
Abstract
Discs-large (DLG) is a multi-PDZ domain-containing protein that belongs to the family of molecular scaffolding proteins known as membrane guanylate kinases or MAGUKs. DLG is a component of the Scribble polarity complex and genetic analyses of DLG in Drosophila have identified a role for the protein in several key biological processes including the regulation of apico-basal polarity of epithelial cells, as well as other polarity processes such as asymmetric cell division and cell invasion. Disturbance of DLG function leads to uncontrolled epithelial cell proliferation and neoplastic transformation, thereby defining DLG as a potential tumour suppressor. However, whether mammalian homologues of DLG (DLG1, DLG2, DLG3 and DLG4) also possess tumour suppressor functions is not known. In this minireview, we focus on the biological functions of DLG1 in human epithelial cells and on how the function of this MAGUK relates to its intracellular location. We examine some of the evidence that implies that DLG has both tumour suppressor and, paradoxically, oncogenic functions depending upon the precise cellular context.
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Affiliation(s)
- Sally Roberts
- School of Cancer Sciences, University of Birmingham, UK
| | - Craig Delury
- School of Cancer Sciences, University of Birmingham, UK
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Massimi P, Zori P, Roberts S, Banks L. Differential regulation of cell-cell contact, invasion and anoikis by hScrib and hDlg in keratinocytes. PLoS One 2012; 7:e40279. [PMID: 22792261 PMCID: PMC3391271 DOI: 10.1371/journal.pone.0040279] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 06/04/2012] [Indexed: 01/31/2023] Open
Abstract
The components of the Scrib/Dlg tumour suppressor complex have complementary roles in Drosophila and loss of both proteins is a common event in many different human tumours. However no studies have directly addressed the respective contributions of loss of hScrib and hDlg in the same human cell background to cellular phenotypes associated with cell transformation. In human HaCaT keratinocytes we show that removal of hScrib greatly reduces cell-cell contact and cell-matrix interactions, and promotes an invasive phenotype. Conversely, in cells lacking hDlg1 cell-cell contacts are maintained and there are decreases in both cell growth and invasion. However, hDlg-depleted cells show increased resistance to a specialized form of apoptosis known as anoikis, to which cells lacking hScrib are highly susceptible. Thus whilst it has been widely assumed that hScrib and hDlg have complementary roles, these studies in fact demonstrate that hScrib and hDlg1 have distinct and opposing functions in human keratinocytes.
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Affiliation(s)
- Paola Massimi
- International Centre For Genetic Engineering and Biotechnology Padriciano 99, Trieste, Italy
| | - Patrizia Zori
- International Centre For Genetic Engineering and Biotechnology Padriciano 99, Trieste, Italy
| | - Sally Roberts
- Department of Cancer Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Lawrence Banks
- International Centre For Genetic Engineering and Biotechnology Padriciano 99, Trieste, Italy
- * E-mail:
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34
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McLaughlin-Drubin ME, Meyers J, Munger K. Cancer associated human papillomaviruses. Curr Opin Virol 2012; 2:459-66. [PMID: 22658985 DOI: 10.1016/j.coviro.2012.05.004] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 05/08/2012] [Accepted: 05/10/2012] [Indexed: 02/07/2023]
Abstract
A small group of human papillomaviruses (HPVs) cause almost all cervical carcinoma and a significant percentage of other anogenital tract and oral carcinoma. Another group of HPVs causes non-melanoma skin cancers in genetically predisposed or immune suppressed patients upon UV exposure. HPV genome replication requires the host cell's DNA synthesis machinery and HPVs encode proteins that maintain differentiated epithelial cells in a replication competent state. The resulting rewiring of cellular signal transduction circuits triggers several innate cellular tumor suppressor responses that HPVs need to inactivate in order to establish persistent and/or productive infections. This review emphasizes this interplay between virus and the infected host cells and points out biological similarities and differences between different groups of HPVs.
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Affiliation(s)
- Margaret E McLaughlin-Drubin
- Division of Infectious Diseases, Brigham and Women's Hospital and Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
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