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Sasvári P, Pettkó-Szandtner A, Wisniewski É, Csépányi-Kömi R. Neutrophil-specific interactome of ARHGAP25 reveals novel partners and regulatory insights. Sci Rep 2024; 14:20106. [PMID: 39210013 PMCID: PMC11362597 DOI: 10.1038/s41598-024-71002-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 08/23/2024] [Indexed: 09/04/2024] Open
Abstract
ARHGAP25, a crucial molecule in immunological processes, serves as a Rac-specific GTPase-activating protein. Its role in cell migration and phagocyte functions, affecting the outcome of complex immunological diseases such as rheumatoid arthritis, renders it a promising target for drug research. Despite its importance, our knowledge of its intracellular interactions is still limited. This study employed proteomic analysis of glutathione S-transferase (GST)-tag pulldowns and co-immunoprecipitation from neutrophilic granulocyte cell lysate, revealing 76 candidates for potential physical interactions that complement ARHGAP25's known profile. Notably, four small GTPases (RAC2, RHOG, ARF4, and RAB27A) exhibited high affinity for ARHGAP25. The ARHGAP25-RAC2 and ARHGAP25-RHOG interactions appeared to be affected by the activation state of the small GTPases, suggesting a GTP-GDP cycle-dependent interaction. In silico dimer prediction pinpointed ARHGAP25's GAP domain as a credible binding interface, suggesting its suitability for GTP hydrolysis. Additionally, a list of Fc receptor-related kinases, phosphatases, and three of the 14-3-3 members were identified as potential partners, with in silico predictions highlighting eight binding sites, presenting novel insight on a potential regulatory mechanism for ARHGAP25.
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Affiliation(s)
- Péter Sasvári
- Department of Physiology, Semmelweis University, Tűzoltó u. 37-47., Budapest, 1085, Hungary
| | - Aladár Pettkó-Szandtner
- Proteomics Research Group, Core Facility, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Éva Wisniewski
- Department of Physiology, Semmelweis University, Tűzoltó u. 37-47., Budapest, 1085, Hungary
| | - Roland Csépányi-Kömi
- Department of Physiology, Semmelweis University, Tűzoltó u. 37-47., Budapest, 1085, Hungary.
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2
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Fei H, Shi X, Sun D, Yang H, Wang D, Li K, Si X, Hu W. Integrated analysis identified the role of three family members of ARHGAP in pancreatic adenocarcinoma. Sci Rep 2024; 14:11790. [PMID: 38783033 PMCID: PMC11116390 DOI: 10.1038/s41598-024-62577-z] [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: 10/02/2023] [Accepted: 05/20/2024] [Indexed: 05/25/2024] Open
Abstract
The Rho GTPase activating protein family (ARHGAPs) is expressed in pancreatic adenocarcinoma (PAAD) but its function is unclear. The aim of this study was to explore the role and potential clinical value of ARHGAPs in PAAD. Using TCGA and GEO databases to analyze expression of ARHGAPs in PAAD and normal tissues. Survival curve was drawn by Kaplan-Meier. ARHGAPs were integrated analyzed by GEPIA2, TIMER, UCLCAN, cBioPortal and R language. Protein level and prognostic value were evaluated via IHC staining or survival analysis. We totally identify 18 differentially expressed (DE) ARHGAPs in PAAD. Among the 18 DE genes, 8 were positively correlated with tumor grade; abnorrmal expression of 5 was positively correlated with copy number variation; expression of 4 was positively correlated with promoter hypomethylation. Multivariate Cox regression identified ARHGAP5, ARHGAP11A, and ARHGAP12 as independent prognostic factors of PAAD. The function of ARHGAPs was mainly related to GTPase activity and signaling, axon guidance, proteoglycans in cancer and focal adhesion. Expression of 7 ARHGAPs was strongly correlated with immune infiltration. Immunohistochemistry showed increased protein levels of ARHGAP5, ARHGAP11A, and ARHGAP12 in PAAD tissues. Survival analysis confirmed a negative correlation between ARHGAP5, ARHGAP11A, and ARHGAP12 expression and patient prognosis. Multivariate Cox regression proved ARHGAP5, ARHGAP11A, and ARHGAP12 could serve as independent prognostic indicators for PAAD. Finally, this study verified ARHGAP5, ARHGAP11A, and ARHGAP12 as independent prognostic factors in PAAD, suggesting their significance for the diagnosis and treatment of PAAD.
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Affiliation(s)
- Haoran Fei
- Department of Hepatobiliary Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222000, Jiangsu, China
- Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Xiao Shi
- Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, College of Pharmacy, Jiangsu Ocean University, Lianyungang, 222005, Jiangsu, China
| | - Dan Sun
- Department of Hepatobiliary Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222000, Jiangsu, China
- Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Haishen Yang
- Department of Hepatobiliary Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222000, Jiangsu, China
| | - Dali Wang
- Department of Hepatobiliary Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222000, Jiangsu, China
| | - Kai Li
- Department of Hepatobiliary Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222000, Jiangsu, China
| | - Xinxin Si
- Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, College of Pharmacy, Jiangsu Ocean University, Lianyungang, 222005, Jiangsu, China.
| | - Wei Hu
- Department of Hepatobiliary Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222000, Jiangsu, China.
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3
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Naeimzadeh Y, Ilbeigi S, Dastsooz H, Rafiee Monjezi M, Mansoori Y, Tabei SMB. Protooncogenic Role of ARHGAP11A and ARHGAP11B in Invasive Ductal Carcinoma: Two Promising Breast Cancer Biomarkers. BIOMED RESEARCH INTERNATIONAL 2023; 2023:8236853. [PMID: 38046902 PMCID: PMC10689071 DOI: 10.1155/2023/8236853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/22/2023] [Accepted: 10/31/2023] [Indexed: 12/05/2023]
Abstract
Invasive duct carcinoma (IDC) is one of the most common types of breast cancer (BC) in women worldwide, with a high risk of malignancy, metastasis, recurrence, and death. So far, molecular patterns among IDC cases have not been fully defined. However, extensive evidence has shown that dysregulated Rho family small GTPases (Rho GTPases) including Rho GTPase activating proteins (RhoGAPs) have important roles in the invasive features of IDCs. In the current study, we analyzed the expression levels of two RhoGAP genes, ARHGAP11A and ARHGAP11B, in The Cancer Genome Atlas (TCGA) breast cancer (BRCA) and also our 51 IDC tumors compared to their matched normal tissues using quantitative polymerase chain reaction (qPCR). Our TCGA data analysis revealed higher expression of ARHGAP11A and ARHGAP11B in various cancers comprising BCs. Also, we found correlations between these genes and other genes in TCGA-BRCA. Moreover, our methylation analysis showed that their promotor methylation had a negative correlation with their overexpression. QPCR revealed their significant upregulation in our tumor samples. Furthermore, we found that the expression level of ARHGAP11A was considerably lower in women who were breastfeeding. Moreover, it had overexpression in cases who had regular menstrual cycles and early age (younger than 14) at menarche. However, ARHGAP11B had a higher expression in HER2-positive tumors versus HER2-positive and ER-positive tumors. Our study found possible protooncogenic roles for these genes and their involvement in IDC pathogenesis and malignancy. Therefore, they can be considered novel prognostic and diagnostic biomarkers for IDC.
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Affiliation(s)
- Y. Naeimzadeh
- School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S. Ilbeigi
- Walther-Straub Institute, Ludwig-Maximilians-Universität München, Munich, Germany
| | - H. Dastsooz
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
- Candiolo, C/o IRCCS, IIGM-Italian Institute for Genomic Medicine, Turin, Italy
- Candiolo Cancer (IT), FPO-IRCCS, Candiolo Cancer Institute, Turin, Italy
| | - M. Rafiee Monjezi
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Y. Mansoori
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - S. M. B. Tabei
- Department of Medical Genetics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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4
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Wisniewski É, Czárán D, Kovács F, Bahurek E, Németh A, Sasvári P, Szanda G, Pettkó-Szandtner A, Klement E, Ligeti E, Csépányi-Kömi R. A novel BRET-Based GAP assay reveals phosphorylation-dependent regulation of the RAC-specific GTPase activating protein ARHGAP25. FASEB J 2022; 36:e22584. [PMID: 36190314 DOI: 10.1096/fj.202200689r] [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: 05/06/2022] [Revised: 09/07/2022] [Accepted: 09/20/2022] [Indexed: 11/11/2022]
Abstract
ARHGAP25, a RAC-specific GTPase activating protein (GAP), is an essential regulator of phagocyte effector functions such as phagocytosis, superoxide production, and transendothelial migration. Furthermore, its complex role in tumor behavior has recently been recognized. We previously demonstrated that phosphorylation of serine 363 in ARHGAP25 regulates hematopoietic stem cells and progenitor cells in mouse bone marrow. However, the significance of other potential phosphorylation sites of ARHGAP25 remained unknown. Now, we developed a novel, real-time bioluminescence resonance energy transfer (BRET) assay to monitor the GAP activity of ARHGAP25 in vitro. Using this approach, we revealed that phosphorylation of S363 and S488, but not that of S379-380, controls ARHGAP25's RACGAP activity. On the other hand, we found in granulocyte-differentiated human PLB-985 cells that superoxide production and actin depolymerization are regulated by residues S363 and S379-380. The present data demonstrate the value of our BRET-GAP assay and show that different phosphorylation patterns regulate ARHGAP25's GAP activity and its effect on superoxide production and phagocytosis.
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Affiliation(s)
- Éva Wisniewski
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Domonkos Czárán
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Fanni Kovács
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Enikő Bahurek
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Afrodité Németh
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Péter Sasvári
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Gergő Szanda
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | | | - Eva Klement
- Laboratory of Proteomics Research, Biological Research Centre, Szeged, Hungary.,Single Cell Omics ACF, Hungarian Centre of Excellence for Molecular Medicine, Szeged, Hungary
| | - Erzsébet Ligeti
- Department of Physiology, Semmelweis University, Budapest, Hungary
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5
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Zhang T, Wang C, Wang K, Liang Y, Liu T, Feng L, Yang X. RacGAP1 promotes the malignant progression of cervical cancer by regulating AP-1 via miR-192 and p-JNK. Cell Death Dis 2022; 13:604. [PMID: 35831303 PMCID: PMC9279451 DOI: 10.1038/s41419-022-05036-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 06/21/2022] [Accepted: 06/24/2022] [Indexed: 01/21/2023]
Abstract
Cervical cancer (CC) is the most frequently diagnosed genital tract cancer in females worldwide. Rac GTPase-activating protein 1 (RacGAP1) is one of the specific GTPase-activating proteins. As a novel tumor protooncogene, overexpression of RacGAP1 was related to the occurrence of various tumors, but its function in CC is still unclear. In this study, bioinformatics analyses showed that RacGAP1 might be a key candidate gene in the progression of CC. RacGAP1 was significantly overexpressed in CC tissues. High RacGAP1 expression was positively associated with poor prognosis. Downregulating RacGAP1 significantly inhibited the proliferation, migration, and invasion of CC cells, while overexpressing RacGAP1 had the opposite effects. Further research showed that miR-192, which plays as a tumor suppressor in CC, was identified as a downstream target of RacGAP1 in CC cells. miR-192 inhibition could partially rescue the decrease in cell proliferation, migration, and invasion caused by RacGAP1 downregulation. In opposite, miR-192 overexpression could decrease the promotion of malignant progression caused by RacGAP1 upregulation. Mechanism studies revealed that RacGAP1 could regulate the expression and phosphorylation of c-Jun, which was the component of AP-1, via miR-192 and p-JNK separately. These findings suggested that RacGAP1 promoted tumorigenicity, migration, and invasion of CC. Therefore, it represented a potential novel prognostic marker in CC and may probably be a therapeutic target.
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Affiliation(s)
- Tianli Zhang
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
- Key Laboratory of Gynecologic Oncology of Shandong Province, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Chunyan Wang
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
- Key Laboratory of Gynecologic Oncology of Shandong Province, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Kun Wang
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
- Key Laboratory of Gynecologic Oncology of Shandong Province, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Ying Liang
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Ting Liu
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Liping Feng
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Xingsheng Yang
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, People's Republic of China.
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6
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Zheng L, Cai X, Song J, Shi H, Zhang J, Ke X, Li H, Chen Y. MicroRNA-30c-2-3p represses malignant progression of gastric adenocarcinoma cells via targeting ARHGAP11A. Bioengineered 2022; 13:14534-14544. [PMID: 35754342 PMCID: PMC9342190 DOI: 10.1080/21655979.2022.2090222] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
MicroRNAs are crucial tumor regulators to tumor development and progression. MiR-30c-2-3p can suppress malignant progression of tumor cells, but no study has reported the modulatory process of miR-30c-2-3p in gastric adenocarcinoma (GA). We herein investigated role of miR-30c-2-3p in GA cells. Here, we evaluated gene level in cancer cells by qRT-PCR. CCK-8, colony formation, flow cytometry, and transwell assays revealed biological functions of miR-30c-2-3p and ARHGAP11A. Genes downstream of miR-30c-2-3p were acquired through bioinformatics analysis. Our results suggested a low level of miR-30c-2-3p in GA tissue and cells, while its high expression could repress the malignant progression and promote cell cycle arrest and apoptosis of GA cells. Besides, ARHGAP11A was downstream of miR-30c-2-3p, with up-regulated ARHGAP11A facilitating malignant progression and repressing cell cycle arrest and apoptosis of GA cells. In addition, changes in GA cell functions caused by high ARHGAP11A expression could be partially offset by enhancing miR-30c-2-3p. Thus, our observations indicated that miR-30c-2-3p was a tumor repressor that could inhibit GA progression via modulating ARHGAP11A.
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Affiliation(s)
- Liang Zheng
- Department of Abdominal Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Xiongchao Cai
- Department of Abdominal Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Jintian Song
- Department of Abdominal Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Huaijing Shi
- Department of Gynecology Surgery, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Jiulong Zhang
- Department of Thoracic Surgical Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Xi Ke
- Department of Abdominal Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Hui Li
- Department of Abdominal Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
| | - Yigui Chen
- Department of Abdominal Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fuzhou, Fujian, China
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7
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Fixing the GAP: the role of RhoGAPs in cancer. Eur J Cell Biol 2022; 101:151209. [DOI: 10.1016/j.ejcb.2022.151209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/29/2022] [Accepted: 02/08/2022] [Indexed: 12/12/2022] Open
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8
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Comer SP. Turning Platelets Off and On: Role of RhoGAPs and RhoGEFs in Platelet Activity. Front Cardiovasc Med 2022; 8:820945. [PMID: 35071371 PMCID: PMC8770426 DOI: 10.3389/fcvm.2021.820945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 12/15/2021] [Indexed: 12/15/2022] Open
Abstract
Platelet cytoskeletal reorganisation is a critical component of platelet activation and thrombus formation in haemostasis. The Rho GTPases RhoA, Rac1 and Cdc42 are the primary drivers in the dynamic reorganisation process, leading to the development of filopodia and lamellipodia which dramatically increase platelet surface area upon activation. Rho GTPases cycle between their active (GTP-bound) and inactive (GDP-bound) states through tightly regulated processes, central to which are the guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). GEFs catalyse the dissociation of GDP by inducing changes in the nucleotide binding site, facilitating GTP binding and activating Rho GTPases. By contrast, while all GTPases possess intrinsic hydrolysing activity, this reaction is extremely slow. Therefore, GAPs catalyse the hydrolysis of GTP to GDP, reverting Rho GTPases to their inactive state. Our current knowledge of these proteins is constantly being updated but there is considerably less known about the functionality of Rho GTPase specific GAPs and GEFs in platelets. In the present review, we discuss GAP and GEF proteins for Rho GTPases identified in platelets, their regulation, biological function and present a case for their further study in platelets.
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Affiliation(s)
- Shane P Comer
- ConwaySPHERE Research Group, UCD Conway Institute, University College Dublin, Dublin, Ireland.,School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
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9
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Chen S, Duan H, Xie Y, Li X, Zhao Y. Expression and prognostic analysis of Rho GTPase-activating protein 11A in lung adenocarcinoma. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:872. [PMID: 34164506 PMCID: PMC8184474 DOI: 10.21037/atm-21-2113] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Background Rho GTPase-activating protein 11A (ARHGAP11A) is a member of the Rho GTPase-activating protein (RhoGAP) subfamily. However, its expression, prognostic significance and clinicopathologic factors correlation in lung adenocarcinoma is still unclear. Methods The original gene expression profile, survival data, and clinical information of patients with lung adenocarcinoma (LUAD) were downloaded from The Cancer Genome Atlas (TCGA) database. The expression difference of ARHGAP11A between LUAD tissues and adjacent normal tissues in the TCGA database was analyzed by using R software, and verified by the Oncomine database and immunohistochemical (IHC) assay of LUAD sections. Logistic regression was applied to analyze the relationship between the expression of ARHGAP11A and clinicopathological factors of LUAD. Kaplan-Meier (KM) survival curves and a Cox proportional-hazards model were selected to evaluate the prognostic significance of ARHGAP11A expression. Gene set enrichment analysis (GSEA) software was applied to screen the tumor signaling pathways associated with the low and high expression group of ARHGAP11A in LUAD. Results The TCGA database showed that the expression of ARHGAP11A was significantly higher in LUAD tissues than in normal tissues (P<0.001). The up-regulation of ARHGAP11A in LUAD was verified by the Oncomine database (P<0.001) and IHC assay (P<0.001). Logistic regression analysis revealed the high expression of ARHGAP11A to be closely related to age, sex, advanced pathological stage, advanced T stage, and lymph node metastasis. The KM plots based on the TCGA and KM plotter databases indicated that patients with LUAD highly expressing ARHGAP11A had a poorer overall survival (OS) than patients with low expression of ARHGAP11A. Multivariate Cox regression analysis showed that the high expression of ARHGAP11A could be an important independent predictor of a poor prognosis of LUAD [hazards ratio (HR) =1.385; P<0.001]. GSEA indicated that 10 signal pathways were significantly enriched in LUAD samples with the ARHGAP11A expression phenotype. Conclusions ARHGAP11A may play a carcinogenic role in the malignant progression of LUAD, and it can be considered as a new independent prognostic factor and potential therapeutic target for LUAD.
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Affiliation(s)
- Shuchen Chen
- Department of Radiation Oncology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.,Department of Thoracic Cancer 1, Cancer Hospital of China Medical University, Liaoning Cancer Hospital and Institute, Shenyang, China
| | - He Duan
- Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
| | - Yusai Xie
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Xiaoling Li
- Department of Thoracic Cancer 1, Cancer Hospital of China Medical University, Liaoning Cancer Hospital and Institute, Shenyang, China
| | - Yuxia Zhao
- Department of Radiation Oncology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
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10
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Ngo ATP, Parra-Izquierdo I, Aslan JE, McCarty OJT. Rho GTPase regulation of reactive oxygen species generation and signalling in platelet function and disease. Small GTPases 2021; 12:440-457. [PMID: 33459160 DOI: 10.1080/21541248.2021.1878001] [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: 10/22/2022] Open
Abstract
Platelets are master regulators and effectors of haemostasis with increasingly recognized functions as mediators of inflammation and immune responses. The Rho family of GTPase members Rac1, Cdc42 and RhoA are known to be major components of the intracellular signalling network critical to platelet shape change and morphological dynamics, thus playing a major role in platelet spreading, secretion and thrombus formation. Initially linked to the regulation of actomyosin contraction and lamellipodia formation, recent reports have uncovered non-canonical functions of platelet RhoGTPases in the regulation of reactive oxygen species (ROS), where intrinsically generated ROS modulate platelet function and contribute to thrombus formation. Platelet RhoGTPases orchestrate oxidative processes and cytoskeletal rearrangement in an interconnected manner to regulate intracellular signalling networks underlying platelet activity and thrombus formation. Herein we review our current knowledge of the regulation of platelet ROS generation by RhoGTPases and their relationship with platelet cytoskeletal reorganization, activation and function.
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Affiliation(s)
- Anh T P Ngo
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Ivan Parra-Izquierdo
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA.,Knight Cardiovascular Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Joseph E Aslan
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA.,Knight Cardiovascular Institute, Oregon Health & Science University, Portland, Oregon, USA.,Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| | - Owen J T McCarty
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
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11
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Yin C, Toiyama Y, Okugawa Y, Shigemori T, Yamamoto A, Ide S, Kitajima T, Fujikawa H, Yasuda H, Okita Y, Hiro J, Yoshiyama S, Ohi M, Araki T, Yao L, Kusunoki M. Rac GTPase-Activating Protein 1 (RACGAP1) as an Oncogenic Enhancer in Esophageal Carcinoma. Oncology 2019; 97:155-163. [PMID: 31216559 DOI: 10.1159/000500592] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 04/24/2019] [Indexed: 11/19/2022]
Abstract
PURPOSE Rac GTPase-activating protein 1 (RACGAP1) is associated with cell proliferation, and there is much evidence of its oncogenic role. This study investigated the clinical importance and functional role of RACGAP1 in esophageal carcinoma (EC). METHODS A total of 81 EC patients were enrolled in the study. We assessed the immunohistochemical score of EC tissues and adjacent normal esophageal mucosae, and then performed multiple cell function tests by means of in vitro experiments to elucidate the functional role of RACGAP1 using RNA interference technology in EC cell lines. RESULTS RACGAP1 was significantly overexpressed in EC tissues compared with the adjacent normal esophageal mucosae (p < 0.0001). Moreover, RACGAP1 overexpression was significantly correlated with poor overall survival (p = 0.032) and disease-free survival (p = 0.012) in EC patients. High RACGAP1 expression was also significantly correlated with the presence of lymphatic invasion (p = 0.012), vessel invasion (p = 0.003), and advanced TNM (tumor-node-metastasis) stage (p = 0.046) in EC patients. In vitro analysis demonstrated that RACGAP1 was involved in the proliferation, tumorigenicity, invasion, migration, and anoikis resistance in EC cells. CONCLUSIONS RACGAP1 plays a pivotal role in EC development, suggesting that it could be used as an indicator of prognosis in EC patients.
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Affiliation(s)
- Chengzeng Yin
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan.,Department of Surgery, China-Japan Friendship Hospital, Beijing, China
| | - Yuji Toiyama
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan,
| | - Yoshinaga Okugawa
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Tsunehiko Shigemori
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Akira Yamamoto
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Shozo Ide
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Takahito Kitajima
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Hiroyuki Fujikawa
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Hiromi Yasuda
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Yoshiki Okita
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Junichiro Hiro
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Shigeyuki Yoshiyama
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Masaki Ohi
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Toshimitsu Araki
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
| | - Li Yao
- Department of Surgery, China-Japan Friendship Hospital, Beijing, China
| | - Masato Kusunoki
- Division of Reparative Medicine, Department of Gastrointestinal and Pediatric Surgery, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie, Japan
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12
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Dai B, Zhang X, Shang R, Wang J, Yang X, Zhang H, Liu Q, Wang D, Wang L, Dou K. Blockade of ARHGAP11A reverses malignant progress via inactivating Rac1B in hepatocellular carcinoma. Cell Commun Signal 2018; 16:99. [PMID: 30545369 PMCID: PMC6293628 DOI: 10.1186/s12964-018-0312-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 12/03/2018] [Indexed: 01/07/2023] Open
Abstract
Background The molecular signaling events involving in high malignancy and poor prognosis of hepatocellular carcinoma (HCC) are extremely complicated. Blockade of currently known targets has not yet led to successful clinical outcome. More understanding about the regulatory mechanisms in HCC is necessary for developing new effective therapeutic strategies for HCC patients. Methods The expression of Rho GTPase-activating protein 11A (ARHGAP11A) was examined in human normal liver and HCC tissues. The correlations between ARHGAP11A expression and clinicopathological stage or prognosis in HCC patients were analyzed. ARHGAP11A was downregulated to determine its role in the proliferation, invasion, migration, epithelial-to-mesenchymal transition (EMT) development, and regulatory signaling of HCC cells in vitro and in vivo. Results ARHGAP11A exhibited high expression in HCC, and was significantly correlated with clinicopathological stage and prognosis in HCC patients. Moreover, ARHGAP11A facilitated Hep3B and MHCC97-H cell proliferation, invasion, migration and EMT development in vitro. ARHGAP11A knockdown significantly inhibited the in vivo growth and metastasis of HCC cells. Furthermore, ARHGAP11A directly interacted with Rac1B independent of Rho GTPase- activating activity. Rac1B blockade effectively interrupted ARHGAP11A-elicited HCC malignant phenotype. Meanwhile, upregulation of Rac1B reversed ARHGAP11A knockdown mediated mesenchymal-to-epithelial transition (MET) development in HCC cells. Conclusion ARHGAP11A facilitates malignant progression in HCC patients via ARHGAP11A-Rac1B interaction. The ARHGAP11A/Rac1B signaling could be a potential therapeutic target in the clinical treatment of HCC. Electronic supplementary material The online version of this article (10.1186/s12964-018-0312-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bin Dai
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Xuan Zhang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Runze Shang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Jianlin Wang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Xisheng Yang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Hong Zhang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Qi Liu
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Desheng Wang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
| | - Lin Wang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
| | - Kefeng Dou
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
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13
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Csépányi-Kömi R, Pásztor M, Bartos B, Ligeti E. The neglected terminators: Rho family GAPs in neutrophils. Eur J Clin Invest 2018; 48 Suppl 2:e12993. [PMID: 29972685 DOI: 10.1111/eci.12993] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 07/02/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND GTPase-activating proteins (GAPs) accelerate the rate of hydrolysis of GTP bound to small GTPases, thereby limiting the prevalence and concentration of the active, GTP-bound form of these proteins. The large number of potential GAPs acting on members of the Rho family of small GTPases raises the question of specificity or redundancy. RESULTS In this review, we summarize experimental data obtained on the role of Rho family GAPs in neutrophils, highlight cases where more than one GAP is involved in a physiological function and show examples that GAPs can be involved not only in termination but also in initiation of cellular processes. We demonstrate that the expression-level regulation of GAPs may also occur in short-living cells such as neutrophils. Finally, we provide insight into the existence and structure of molecular complexes in which Rho family GAPs are involved. CONCLUSION GAPs play more complex and varied roles than being simple terminators of cellular processes.
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Affiliation(s)
| | - Máté Pásztor
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Balázs Bartos
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Erzsébet Ligeti
- Department of Physiology, Semmelweis University, Budapest, Hungary
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14
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Shin Y, Kim YW, Kim H, Shin N, Kim TS, Kwon TK, Choi JH, Chang JS. RASAL3 preferentially stimulates GTP hydrolysis of the Rho family small GTPase Rac2. Biomed Rep 2018; 9:241-246. [PMID: 30271600 DOI: 10.3892/br.2018.1119] [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: 05/11/2018] [Accepted: 06/28/2018] [Indexed: 11/05/2022] Open
Abstract
Members of the Ras superfamily of small G-proteins serve as molecular switches of intracellular signaling pathways. Rac2 is a Rho subfamily GTPase switch that is specifically expressed in hematopoietic cells and regulates AKT activation in cell signaling. Ras activating protein-like 3 (RASAL3) is the recently identified Ras GTPase activating protein (GAP) that is also specifically expressed in hematopoietic cells and stimulates p21ras GTPase activity. The restricted expression of both Rac2 and RASAL3 suggests that they may serve critical roles in hematopoietic cell signaling. Here in the present study demonstrates that the catalytic domain of RASAL3 may also be able to interact with Rac2 and stimulate its GTPase activity in vitro. By contrast, p50 rhoGAP molecules did not markedly affect Rac2 GTPase activity, but did accelerate the activity of other Rho GTPases, including Rac1, RhoA and Cdc42. Collectively, the present results indicate, seemingly for the first time, that GAP activity for Rac2 is regulated by the RasGAP family protein, RASAL3.
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Affiliation(s)
- Yoonjae Shin
- Department of Life Science, College of Science and Technology, Daejin University, Pocheon-Si, Gyeonggi-Do 11159, South Korea
| | - Yong Woo Kim
- Department of Life Science, College of Science and Technology, Daejin University, Pocheon-Si, Gyeonggi-Do 11159, South Korea
| | - Hyemin Kim
- Department of Life Science, College of Science and Technology, Daejin University, Pocheon-Si, Gyeonggi-Do 11159, South Korea
| | - Nakyoung Shin
- Department of Life Science, College of Science and Technology, Daejin University, Pocheon-Si, Gyeonggi-Do 11159, South Korea
| | - Tae Sung Kim
- Department of Life Science, College of Science and Technology, Daejin University, Pocheon-Si, Gyeonggi-Do 11159, South Korea
| | - Taeg Kyu Kwon
- Department of Immunology and Physiology, School of Medicine, Keimyung University, Daegu 42601, South Korea
| | - Jang Hyun Choi
- Department of Biological Sciences, Division of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
| | - Jong-Soo Chang
- Department of Life Science, College of Science and Technology, Daejin University, Pocheon-Si, Gyeonggi-Do 11159, South Korea
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15
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Wang D, Qian X, Rajaram M, Durkin ME, Lowy DR. DLC1 is the principal biologically-relevant down-regulated DLC family member in several cancers. Oncotarget 2018; 7:45144-45157. [PMID: 27174913 PMCID: PMC5216712 DOI: 10.18632/oncotarget.9266] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 04/10/2016] [Indexed: 01/12/2023] Open
Abstract
The RHO family of RAS-related GTPases in tumors may be activated by reduced levels of RHO GTPase accelerating proteins (GAPs). One common mechanism is decreased expression of one or more members of the Deleted in Liver Cancer (DLC) family of Rho-GAPs, which comprises three closely related genes (DLC1, DLC2, and DLC3) that are down-regulated in a wide range of malignancies. Here we have studied their comparative biological activity in cultured cells and used publicly available datasets to examine their mRNA expression patterns in normal and cancer tissues, and to explore their relationship to cancer phenotypes and survival outcomes. In The Cancer Genome Atlas (TCGA) database, DLC1 expression predominated in normal lung, breast, and liver, but not in colorectum. Conversely, reduced DLC1 expression predominated in lung squamous cell carcinoma (LSC), lung adenocarcinoma (LAD), breast cancer, and hepatocellular carcinoma (HCC), but not in colorectal cancer. Reduced DLC1 expression was frequently associated with promoter methylation in LSC and LAD, while DLC1 copy number loss was frequent in HCC. DLC1 expression was higher in TCGA LAD patients who remained cancer-free, while low DLC1 had a poorer prognosis than low DLC2 or low DLC3 in a more completely annotated database. The poorest prognosis was associated with low expression of both DLC1 and DLC2 (P < 0.0001). In cultured cells, the three genes induced a similar reduction of Rho-GTP and cell migration. We conclude that DLC1 is the predominant family member expressed in several normal tissues, and its expression is preferentially reduced in common cancers at these sites.
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Affiliation(s)
- Dunrui Wang
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiaolan Qian
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Megha Rajaram
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.,Current address: BioTek Instruments Inc., Winooski, VT 05404, USA
| | - Marian E Durkin
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Douglas R Lowy
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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16
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Aguilar-Rojas A, Maya-Núñez G, Huerta-Reyes M, Pérez-Solis MA, Silva-García R, Guillén N, Olivo-Marin JC. Activation of human gonadotropin-releasing hormone receptor promotes down regulation of ARHGAP18 and regulates the cell invasion of MDA-MB-231 cells. Mol Cell Endocrinol 2018; 460:94-103. [PMID: 28709956 DOI: 10.1016/j.mce.2017.07.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/29/2017] [Accepted: 07/10/2017] [Indexed: 02/08/2023]
Abstract
The Gonadotropin-Releasing Hormone Receptor (GnRHR) is expressed mainly in the gonadotrope membrane of the adenohypophysis and its natural ligand, the Gonadotropin-Releasing Hormone (GnRH), is produced in anterior hypothalamus. Furthermore, both molecules are also present in the membrane of cells derived from other reproductive tissues such as the breast, endometrium, ovary, and prostate, as well as in tumors derived from these tissues. The functions of GnRH receptor and its hormone in malignant cells have been related with the decrease of proliferation and the invasiveness of those tumors however, little is known about the molecules associated with the signaling pathways regulated by both molecules in malignant cells. To further analyze the potential mechanisms employed by the GnRHR/GnRH system to reduce the tumorigenesis of the highly invasive breast cancer cell line MDA-MB-231, we performed microarrays experiments to evaluated changes in genes expression and validate these modifications by functional assays. We show that activation of human GnRHR is able to diminish the expression and therefore functions of the Rho GTPase-Activating Protein 18 (ARHGAP18). Decrease of this GAP following GnRHR activation, correlates to the higher of cell adhesion and also with reduction of tumor cell invasion, supporting the notion that GnRHR triggers intracellular signaling pathways that acts through ARHGAP18. On the contrary, although a decline of cellular proliferation was observed during GnRHR activation in MDA-MB-231, this was independent of ARHGAP18 showing the complex system in which is involved the signaling pathways regulated by the GnRHR/GnRH system.
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Affiliation(s)
- Arturo Aguilar-Rojas
- Instituto Mexicano del Seguro Social (IMSS), Unidad de Investigación Médica en Medicina Reproductiva, UMAE No. 4, Ciudad de México, Mexico; Institut Pasteur, Unité d'Analyse d'Images Biologiques, 25 Rue du Dr Roux, F-75015 Paris, France; Centre National de la Recherche Scientifique, CNRS UMR3691, 25 Rue du Dr Roux, F-75015 Paris, France.
| | - Guadalupe Maya-Núñez
- Instituto Mexicano del Seguro Social (IMSS), Unidad de Investigación Médica en Medicina Reproductiva, UMAE No. 4, Ciudad de México, Mexico
| | - Maira Huerta-Reyes
- IMSS, Unidad de Investigación Médica en Farmacología, Hospital de Especialidades, Centro Médico Nacional Siglo XXI (CMN-SXXI), Ciudad de México, Mexico
| | - Marco Allán Pérez-Solis
- Instituto Mexicano del Seguro Social (IMSS), Unidad de Investigación Médica en Medicina Reproductiva, UMAE No. 4, Ciudad de México, Mexico
| | - Raúl Silva-García
- IMSS, Unidad de Investigación Médica en Inmunología, Hospital de Pediatría, CMN-SXXI, Ciudad de México, Mexico
| | - Nancy Guillén
- Centre National de la Recherche Scientifique, CNRS-ERL9195, 25 Rue du Dr Roux, F-75015 Paris, France
| | - Jean-Christophe Olivo-Marin
- Institut Pasteur, Unité d'Analyse d'Images Biologiques, 25 Rue du Dr Roux, F-75015 Paris, France; Centre National de la Recherche Scientifique, CNRS UMR3691, 25 Rue du Dr Roux, F-75015 Paris, France
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17
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Aspenström P. BAR Domain Proteins Regulate Rho GTPase Signaling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1111:33-53. [PMID: 30151649 DOI: 10.1007/5584_2018_259] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The Bin-Amphiphysin-Rvs (BAR) domain is a membrane lipid binding domain present in a wide variety of proteins, often proteins with a role in Rho-regulated signaling pathways. BAR domains do not only confer binding to lipid bilayers, they also possess a membrane sculpturing ability and thereby directly control the topology of biomembranes. BAR domain-containing proteins participate in a plethora of physiological processes but the common denominator is their capacity to link membrane dynamics to actin dynamics and thereby integrate processes such as endocytosis, exocytosis, vesicle trafficking, cell morphogenesis and cell migration. The Rho family of small GTPases constitutes an important bridging theme for many BAR domain-containing proteins. This review article will focus predominantly on the role of BAR proteins as regulators or effectors of Rho GTPases and it will only briefly discuss the structural and biophysical function of the BAR domains.
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Affiliation(s)
- Pontus Aspenström
- Department of Microbiology, and Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
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18
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Wang C, Wang W, Liu Y, Yong M, Yang Y, Zhou H. Rac GTPase activating protein 1 promotes oncogenic progression of epithelial ovarian cancer. Cancer Sci 2017; 109:84-93. [PMID: 29095547 PMCID: PMC5765294 DOI: 10.1111/cas.13434] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/27/2017] [Accepted: 10/12/2017] [Indexed: 12/15/2022] Open
Abstract
Rac GTPase activating protein 1 (RacGAP1) can regulate cytokinesis and cell differentiation. The oncogenic role of RacGAP1 has been partially studied in gastric cancer, colorectal cancer, and breast cancer. In the present study, we endeavor to evaluate its expression and functions in epithelial ovarian cancer (EOC). We retrospectively collected the clinicopathological information of 117 patients who underwent curative surgery for EOC. Expression of RacGAP1 protein in primary tumor tissues was evaluated by immunohistochemistry, which was significantly associated with tumor pathological grade, tumor stage, and lymph node metastasis. Patients with lower RacGAP1 level had a longer survival time and lower recurrence risk. Multivariate results identified the independent prognostic role of RacGAP1 for both recurrence and survival in EOC patients. Cellular studies showed that RacGAP1 can positively regulate the activation of RhoA and Erk proteins. In addition, wound healing assay and Transwell assay found that RacGAP1 can up-regulate the migration and invasion process of EOC cells, respectively. In all, our results not only confirmed the prognostic role of RacGAP1 for recurrence and survival in EOC patients, but also highlighted its possible potency for drug development.
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Affiliation(s)
- Chuanjiang Wang
- Department of Reproductive Center, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Wenxia Wang
- Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, China
| | - Yujuan Liu
- Department of Obstetrics and Gynecology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Min Yong
- Department of Obstetrics and Gynecology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Yamei Yang
- Department of Obstetrics and Gynecology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Honggui Zhou
- Department of Obstetrics and Gynecology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
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19
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Bidaud-Meynard A, Binamé F, Lagrée V, Moreau V. Regulation of Rho GTPase activity at the leading edge of migrating cells by p190RhoGAP. Small GTPases 2017; 10:99-110. [PMID: 28287334 DOI: 10.1080/21541248.2017.1280584] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cell migration, a key feature of embryonic development, immunity, angiogenesis, and tumor metastasis, is based on the coordinated regulation of actin dynamics and integrin-mediated adhesion. Rho GTPases play a major role in this phenomenon by regulating the onset and maintenance of actin-based protruding structures at cell leading edges (i.e. lamellipodia and filopodia) and contractile structures (i.e., stress fibers) at their trailing edge. While spatio-temporal analysis demonstrated the tight regulation of Rho GTPases at the migration front during cell locomotion, little is known about how the main regulators of Rho GTPase activity, such as GAPs, GEFs and GDIs, play a role in this process. In this review, we focus on a major negative regulator of RhoA, p190RhoGAP-A and its close isoform p190RhoGAP-B, which are necessary for efficient cell migration. Recent studies, including our, demonstrated that p190RhoGAP-A localization and activity undergo a complex regulatory mechanism, accounting for the tight regulation of RhoA, but also other members of the Rho GTPase family, at the cell periphery.
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Affiliation(s)
- Aurélien Bidaud-Meynard
- a Institut National de la Santé et de la Recherche Médicale , Bordeaux , France.,b Université de Bordeaux, Unité Mixte de Recherche 1053 Bordeaux Research In Translational Oncology , Bordeaux , France
| | - Fabien Binamé
- a Institut National de la Santé et de la Recherche Médicale , Bordeaux , France.,b Université de Bordeaux, Unité Mixte de Recherche 1053 Bordeaux Research In Translational Oncology , Bordeaux , France
| | - Valérie Lagrée
- a Institut National de la Santé et de la Recherche Médicale , Bordeaux , France.,b Université de Bordeaux, Unité Mixte de Recherche 1053 Bordeaux Research In Translational Oncology , Bordeaux , France
| | - Violaine Moreau
- a Institut National de la Santé et de la Recherche Médicale , Bordeaux , France.,b Université de Bordeaux, Unité Mixte de Recherche 1053 Bordeaux Research In Translational Oncology , Bordeaux , France
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20
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Lawson CD, Der CJ. Filling GAPs in our knowledge: ARHGAP11A and RACGAP1 act as oncogenes in basal-like breast cancers. Small GTPases 2016; 9:290-296. [PMID: 27657701 DOI: 10.1080/21541248.2016.1220350] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Like RAS proteins, the aberrant function of RHO family small GTPases has been implicated in driving cancer development and growth. However, unlike the RAS family, where gain-of-function missense mutations are found in ∼25% of all human cancers, missense mutations are relatively rare in RHO proteins. Instead, altered RHO activity in cancer more commonly arises through the aberrant functions of RHO GTPase regulators. In many cancer types, altered expression and/or mutation of RHO-selective guanine nucleotide exchange factors (RHOGEFs) or GTPase-activating proteins (RHOGAPs), which activate or inactivate RHO GTPases, respectively, is observed. For example, deletion or loss of expression of the RHOA GAP DLC1 is well-established to drive cancer growth. Recently, we identified high expression of 2 RHOGAPs, ARHGAP11A and RACGAP1, in the basal-like breast cancer subtype. Unexpectedly, both of these RHOA GAPs exhibited properties of oncoproteins rather than tumor suppressors, in contrast to DLC1. In this commentary, we summarize our findings and speculate that different RHOA GAPs can play distinct roles in cancer depending on their spatial regulation and cancer type context. We also evaluate our results in light of recently-described cancer genome sequencing studies that have identified loss-of-function mutations of RHOA in specific cancer types.
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Affiliation(s)
- Campbell D Lawson
- a Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus , London , UK
| | - Channing J Der
- b Department of Pharmacology and Lineberger Comprehensive Cancer Center , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
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21
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Amin E, Jaiswal M, Derewenda U, Reis K, Nouri K, Koessmeier KT, Aspenström P, Somlyo AV, Dvorsky R, Ahmadian MR. Deciphering the Molecular and Functional Basis of RHOGAP Family Proteins: A SYSTEMATIC APPROACH TOWARD SELECTIVE INACTIVATION OF RHO FAMILY PROTEINS. J Biol Chem 2016; 291:20353-71. [PMID: 27481945 PMCID: PMC5034035 DOI: 10.1074/jbc.m116.736967] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/15/2016] [Indexed: 12/30/2022] Open
Abstract
RHO GTPase-activating proteins (RHOGAPs) are one of the major classes of regulators of the RHO-related protein family that are crucial in many cellular processes, motility, contractility, growth, differentiation, and development. Using database searches, we extracted 66 distinct human RHOGAPs, from which 57 have a common catalytic domain capable of terminating RHO protein signaling by stimulating the slow intrinsic GTP hydrolysis (GTPase) reaction. The specificity of the majority of the members of RHOGAP family is largely uncharacterized. Here, we comprehensively investigated the sequence-structure-function relationship between RHOGAPs and RHO proteins by combining our in vitro data with in silico data. The activity of 14 representatives of the RHOGAP family toward 12 RHO family proteins was determined in real time. We identified and structurally verified hot spots in the interface between RHOGAPs and RHO proteins as critical determinants for binding and catalysis. We have found that the RHOGAP domain itself is nonselective and in some cases rather inefficient under cell-free conditions. Thus, we propose that other domains of RHOGAPs confer substrate specificity and fine-tune their catalytic efficiency in cells.
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Affiliation(s)
- Ehsan Amin
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Mamta Jaiswal
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Urszula Derewenda
- the Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908, and
| | - Katarina Reis
- the Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Kazem Nouri
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Katja T Koessmeier
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Pontus Aspenström
- the Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Avril V Somlyo
- the Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908, and
| | - Radovan Dvorsky
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany,
| | - Mohammad R Ahmadian
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany,
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22
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Csépányi-Kömi R, Wisniewski É, Bartos B, Lévai P, Németh T, Balázs B, Kurz ARM, Bierschenk S, Sperandio M, Ligeti E. Rac GTPase Activating Protein ARHGAP25 Regulates Leukocyte Transendothelial Migration in Mice. THE JOURNAL OF IMMUNOLOGY 2016; 197:2807-15. [PMID: 27566826 DOI: 10.4049/jimmunol.1502342] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 07/21/2016] [Indexed: 12/31/2022]
Abstract
ARHGAP25 is a Rac-specific GTPase-activating protein that is expressed primarily in hematopoietic cells. The involvement of ARHGAP25 in regulating the recruitment of leukocytes to inflammatory sites was investigated in genetically modified mice. Using intravital microscopy, we show that Arhgap25 deficiency affects all steps of leukocyte recruitment with a predominant enhancement of transendothelial migration of neutrophilic granulocytes. Increased transmigration of Arhgap25-deficient leukocytes is demonstrated in inflamed cremaster muscle venules, in a peritonitis model, and in an in vitro chemotaxis assay. Using bone marrow chimeric mice lacking ARHGAP25 in the hematopoietic compartment, we show that enhanced migration in the absence of ARHGAP25 is due to defective leukocyte function. In search for potential mechanisms of ARHGAP25-regulated migration of neutrophils, we detected an increase in the amount of active, GTP-bound Rac and Rac-dependent cytoskeletal changes in the absence of ARHGAP25, suggesting a critical role of ARHGAP25 in counterbalancing the Rac-activating effect of nucleotide exchange factors. Taken together, using Arhgap25-deficient mice, we identified ARHGAP25 as a relevant negative regulator of leukocyte transendothelial migration.
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Affiliation(s)
- Roland Csépányi-Kömi
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and Walter-Brendel-Zentrum für Experimentelle Medizin, Ludwig-Maximilians Universität, 80539 Munich, Germany
| | - Éva Wisniewski
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and
| | - Balázs Bartos
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and
| | - Petra Lévai
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and
| | - Tamás Németh
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and
| | - Bernadett Balázs
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and
| | - Angela R M Kurz
- Walter-Brendel-Zentrum für Experimentelle Medizin, Ludwig-Maximilians Universität, 80539 Munich, Germany
| | - Susanne Bierschenk
- Walter-Brendel-Zentrum für Experimentelle Medizin, Ludwig-Maximilians Universität, 80539 Munich, Germany
| | - Markus Sperandio
- Walter-Brendel-Zentrum für Experimentelle Medizin, Ludwig-Maximilians Universität, 80539 Munich, Germany
| | - Erzsébet Ligeti
- Department of Physiology, Semmelweis University, 1094 Budapest, Hungary; and
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23
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Lawson CD, Fan C, Mitin N, Baker NM, George SD, Graham DM, Perou CM, Burridge K, Der CJ, Rossman KL. Rho GTPase Transcriptome Analysis Reveals Oncogenic Roles for Rho GTPase-Activating Proteins in Basal-like Breast Cancers. Cancer Res 2016; 76:3826-37. [PMID: 27216196 DOI: 10.1158/0008-5472.can-15-2923] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 03/18/2016] [Indexed: 02/06/2023]
Abstract
The basal-like breast cancer (BLBC) subtype accounts for a disproportionately high percentage of overall breast cancer mortality. The current therapeutic options for BLBC need improvement; hence, elucidating signaling pathways that drive BLBC growth may identify novel targets for the development of effective therapies. Rho GTPases have previously been implicated in promoting tumor cell proliferation and metastasis. These proteins are inactivated by Rho-selective GTPase-activating proteins (RhoGAP), which have generally been presumed to act as tumor suppressors. Surprisingly, RNA-Seq analysis of the Rho GTPase signaling transcriptome revealed high expression of several RhoGAP genes in BLBC tumors, raising the possibility that these genes may be oncogenic. To evaluate this, we examined the roles of two of these RhoGAPs, ArhGAP11A (also known as MP-GAP) and RacGAP1 (also known as MgcRacGAP), in promoting BLBC. Both proteins were highly expressed in human BLBC cell lines, and knockdown of either gene resulted in significant defects in the proliferation of these cells. Knockdown of ArhGAP11A caused CDKN1B/p27-mediated arrest in the G1 phase of the cell cycle, whereas depletion of RacGAP1 inhibited growth through the combined effects of cytokinesis failure, CDKN1A/p21-mediated RB1 inhibition, and the onset of senescence. Random migration was suppressed or enhanced by the knockdown of ArhGAP11A or RacGAP1, respectively. Cell spreading and levels of GTP-bound RhoA were increased upon depletion of either RhoGAP. We have established that, via the suppression of RhoA, ArhGAP11A and RacGAP1 are both critical drivers of BLBC growth, and propose that RhoGAPs can act as oncogenes in cancer. Cancer Res; 76(13); 3826-37. ©2016 AACR.
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Affiliation(s)
- Campbell D Lawson
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Cheng Fan
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Natalia Mitin
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Nicole M Baker
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Samuel D George
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - David M Graham
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Charles M Perou
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Keith Burridge
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Channing J Der
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
| | - Kent L Rossman
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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24
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Nagy Z, Wynne K, von Kriegsheim A, Gambaryan S, Smolenski A. Cyclic Nucleotide-dependent Protein Kinases Target ARHGAP17 and ARHGEF6 Complexes in Platelets. J Biol Chem 2015; 290:29974-83. [PMID: 26507661 DOI: 10.1074/jbc.m115.678003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Indexed: 01/01/2023] Open
Abstract
Endothelial cells release prostacyclin (PGI2) and nitric oxide (NO) to inhibit platelet functions. PGI2 and NO effects are mediated by cyclic nucleotides, cAMP- and cGMP-dependent protein kinases (PKA, PKG), and largely unknown PKA and PKG substrate proteins. The small G-protein Rac1 plays a key role in platelets and was suggested to be a target of cyclic nucleotide signaling. We confirm that PKA and PKG activation reduces Rac1-GTP levels. Screening for potential mediators of this effect resulted in the identification of the Rac1-specific GTPase-activating protein ARHGAP17 and the guanine nucleotide exchange factor ARHGEF6 as new PKA and PKG substrates in platelets. We mapped the PKA/PKG phosphorylation sites to serine 702 on ARHGAP17 using Phos-tag gels and to serine 684 on ARHGEF6. We show that ARHGAP17 binds to the actin-regulating CIP4 protein in platelets and that Ser-702 phosphorylation interferes with this interaction. Reduced CIP4 binding results in enhanced inhibition of cell migration by ARHGAP17. Furthermore, we show that ARHGEF6 is constitutively linked to GIT1, a GAP of Arf family small G proteins, and that ARHGEF6 phosphorylation enables binding of the 14-3-3 adaptor protein to the ARHGEF6/GIT1 complex. PKA and PKG induced rearrangement of ARHGAP17- and ARHGEF6-associated protein complexes might contribute to Rac1 regulation and platelet inhibition.
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Affiliation(s)
- Zoltan Nagy
- From the UCD Conway Institute and the School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Kieran Wynne
- Mass Spectrometry Resource, UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | | | - Stepan Gambaryan
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 44 Thorez Prospect, St. Petersburg, 194223 Russia
| | - Albert Smolenski
- From the UCD Conway Institute and the School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland,
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25
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Lawson CD, Burridge K. The on-off relationship of Rho and Rac during integrin-mediated adhesion and cell migration. Small GTPases 2014; 5:e27958. [PMID: 24607953 DOI: 10.4161/sgtp.27958] [Citation(s) in RCA: 218] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Rho GTPases play an essential role in regulating cell spreading, adhesion, and migration downstream of integrin engagement with the extracellular matrix. In this review, we focus on RhoA and Rac1--2 Rho GTPases that are required for efficient adhesion and migration--and describe how specific guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs) regulate the extensive crosstalk that exists between them. In particular, we assess the role of GEFs and GAPs in light of recent, unexpected evidence concerning the spatiotemporal relationship between RhoA and Rac1 at the leading edge of migrating cells. Force is increasingly recognized as a key regulator of cell adhesion and we highlight the role of GEFs and GAPs in mechanotransduction, before debating the controversial role of tension in focal adhesion maturation.
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Affiliation(s)
- Campbell D Lawson
- Department of Cell Biology and Physiology; Lineberger Comprehensive Cancer Center; University of North Carolina at Chapel Hill; Chapel Hill, NC USA
| | - Keith Burridge
- Department of Cell Biology and Physiology; Lineberger Comprehensive Cancer Center; University of North Carolina at Chapel Hill; Chapel Hill, NC USA
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26
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Lőrincz ÁM, Szarvas G, Smith SME, Ligeti E. Role of Rac GTPase activating proteins in regulation of NADPH oxidase in human neutrophils. Free Radic Biol Med 2014; 68:65-71. [PMID: 24321316 DOI: 10.1016/j.freeradbiomed.2013.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 11/15/2013] [Accepted: 12/01/2013] [Indexed: 10/25/2022]
Abstract
Precise spatiotemporal regulation of O2(-)-generating NADPH oxidases (Nox) is a vital requirement. In the case of Nox1-3, which depend on the small GTPase Rac, acceleration of GTP hydrolysis by GTPase activating protein (GAP) could represent a feasible temporal control mechanism. Our goal was to investigate the molecular interactions between RacGAPs and phagocytic Nox2 in neutrophilic granulocytes. In structural studies we revealed that simultaneous interaction of Rac with its effector protein p67(phox) and regulatory protein RacGAP was sterically possible. The effect of RacGAPs was experimentally investigated in a cell-free O2(-)-generating system consisting of isolated membranes and recombinant p47(phox) and p67(phox) proteins. Addition of soluble RacGAPs decreased O2(-) production and there was no difference in the effect of four RacGAPs previously identified in neutrophils. Depletion of membrane-associated RacGAPs had a selective effect: a decrease in ARHGAP1 or ARHGAP25 level increased O2(-) production but a depletion of ARHGAP35 had no effect. Only membrane-localized RacGAPs seem to be able to interact with Rac when it is assembled in the Nox2 complex. Thus, in neutrophils multiple RacGAPs are involved in the control of O2(-) production by Nox2, allowing selective regulation via different signaling pathways.
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Affiliation(s)
- Ákos M Lőrincz
- Department of Physiology, Semmelweis University, Tűzoltó u. 37-47, 1094 Budapest, Hungary
| | - Gábor Szarvas
- Department of Physiology, Semmelweis University, Tűzoltó u. 37-47, 1094 Budapest, Hungary
| | - Susan M E Smith
- Department of Biology and Physics, Kennesaw State University, 1000 Chastain Road, Building 12, Room 308, Kennesaw, GA 30144, USA
| | - Erzsébet Ligeti
- Department of Physiology, Semmelweis University, Tűzoltó u. 37-47, 1094 Budapest, Hungary.
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