1
|
Parise A, Magistrato A. Assessing the mechanism of fast-cycling cancer-associated mutations of Rac1 small Rho GTPase. Protein Sci 2024; 33:e4939. [PMID: 38501467 PMCID: PMC10949326 DOI: 10.1002/pro.4939] [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: 09/07/2023] [Revised: 01/23/2024] [Accepted: 02/08/2024] [Indexed: 03/20/2024]
Abstract
Rho-GTPases proteins function as molecular switches alternating from an active to an inactive state upon Guanosine triphosphate (GTP) binding and hydrolysis to Guanosine diphosphate (GDP). Among them, Rac subfamily regulates cell dynamics, being overexpressed in distinct cancer types. Notably, these proteins are object of frequent cancer-associated mutations at Pro29 (P29S, P29L, and P29Q). To assess the impact of these mutations on Rac1 structure and function, we performed extensive all-atom molecular dynamics simulations on wild-type (wt) and oncogenic isoforms of this protein in GDP- and GTP-bound states. Our results unprecedentedly elucidate that P29Q/S-induced structural and dynamical perturbations of Rac1 core domain weaken the binding of the catalytic site Mg2+ ion, and reduce the GDP residence time within protein, enhancing the GDP/GTP exchange rate and Rac1 activity. This broadens our knowledge of the role of cancer-associated mutations on small GTPases mechanism supplying valuable information for future drug discovery efforts targeting specific Rac1 isoforms.
Collapse
Affiliation(s)
- Angela Parise
- Consiglio Nazionale delle ricerche (CNR)‐IOM c/o International School for Advanced Studies (SISSA/ISAS)TriesteItaly
| | - Alessandra Magistrato
- Consiglio Nazionale delle ricerche (CNR)‐IOM c/o International School for Advanced Studies (SISSA/ISAS)TriesteItaly
| |
Collapse
|
2
|
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
|
3
|
Scala M, Nishikawa M, Nagata KI, Striano P. Pathophysiological Mechanisms in Neurodevelopmental Disorders Caused by Rac GTPases Dysregulation: What's behind Neuro-RACopathies. Cells 2021; 10:3395. [PMID: 34943902 PMCID: PMC8699292 DOI: 10.3390/cells10123395] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/23/2021] [Accepted: 11/30/2021] [Indexed: 02/07/2023] Open
Abstract
Rho family guanosine triphosphatases (GTPases) regulate cellular signaling and cytoskeletal dynamics, playing a pivotal role in cell adhesion, migration, and cell cycle progression. The Rac subfamily of Rho GTPases consists of three highly homologous proteins, Rac 1-3. The proper function of Rac1 and Rac3, and their correct interaction with guanine nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs) are crucial for neural development. Pathogenic variants affecting these delicate biological processes are implicated in different medical conditions in humans, primarily neurodevelopmental disorders (NDDs). In addition to a direct deleterious effect produced by genetic variants in the RAC genes, a dysregulated GTPase activity resulting from an abnormal function of GEFs and GAPs has been involved in the pathogenesis of distinctive emerging conditions. In this study, we reviewed the current pertinent literature on Rac-related disorders with a primary neurological involvement, providing an overview of the current knowledge on the pathophysiological mechanisms involved in the neuro-RACopathies.
Collapse
Affiliation(s)
- Marcello Scala
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genoa, Italy;
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Masashi Nishikawa
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai 480-0392, Japan; (M.N.); (K.-i.N.)
| | - Koh-ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai 480-0392, Japan; (M.N.); (K.-i.N.)
- Department of Neurochemistry, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Nagoya 466-8550, Japan
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genoa, Italy;
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| |
Collapse
|
4
|
Gahankari A, Dong C, Bartoletti G, Galazo M, He F. Deregulated Rac1 Activity in Neural Crest Controls Cell Proliferation, Migration and Differentiation During Midbrain Development. Front Cell Dev Biol 2021; 9:704769. [PMID: 34557485 PMCID: PMC8452869 DOI: 10.3389/fcell.2021.704769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
Mutations in RAC1 allele are implicated in multiple brain tumors, indicating a rigorous control of Rac1 activity is required for neural tissue normal development and homeostasis. To understand how elevated Rac1 activity affects neural crest cells (NCCs) development, we have generated Rac1 CA ;Wnt1-Cre2 mice, in which a constitutively active Rac1 G12V mutant is expressed specifically in NCCs derivatives. Our results revealed that augmented Rac1 activity leads to enlarged midbrain and altered cell density, accompanied by increased NCCs proliferation rate and misrouted cell migration. Interestingly, our experimental data also showed that elevated Rac1 activity in NCCs disrupts regionalization of dopaminergic neuron progenitors in the ventral midbrain and impairs their differentiation. These findings shed light on the mechanisms of RAC1 mutation correlated brain tumor at the cellular and molecular level.
Collapse
Affiliation(s)
- Apurva Gahankari
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
| | - Chunmin Dong
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
| | - Garrett Bartoletti
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
| | - Maria Galazo
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States.,Tulane Brain Institute, Tulane University, New Orleans, LA, United States
| | - Fenglei He
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
| |
Collapse
|
5
|
Crosas-Molist E, Samain R, Kohlhammer L, Orgaz J, George S, Maiques O, Barcelo J, Sanz-Moreno V. RhoGTPase Signalling in Cancer Progression and Dissemination. Physiol Rev 2021; 102:455-510. [PMID: 34541899 DOI: 10.1152/physrev.00045.2020] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Rho GTPases are a family of small G proteins that regulate a wide array of cellular processes related to their key roles controlling the cytoskeleton. On the other hand, cancer is a multi-step disease caused by the accumulation of genetic mutations and epigenetic alterations, from the initial stages of cancer development when cells in normal tissues undergo transformation, to the acquisition of invasive and metastatic traits, responsible for a large number of cancer related deaths. In this review, we discuss the role of Rho GTPase signalling in cancer in every step of disease progression. Rho GTPases contribute to tumour initiation and progression, by regulating proliferation and apoptosis, but also metabolism, senescence and cell stemness. Rho GTPases play a major role in cell migration, and in the metastatic process. They are also involved in interactions with the tumour microenvironment and regulate inflammation, contributing to cancer progression. After years of intensive research, we highlight the importance of relevant models in the Rho GTPase field, and we reflect on the therapeutic opportunities arising for cancer patients.
Collapse
Affiliation(s)
- Eva Crosas-Molist
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Remi Samain
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Leonie Kohlhammer
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Jose Orgaz
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom.,Instituto de Investigaciones Biomédicas 'Alberto Sols', CSIC-UAM, 28029, Madrid, Spain
| | - Samantha George
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Oscar Maiques
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Jaume Barcelo
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | | |
Collapse
|
6
|
The Role of CTHRC1 in Regulation of Multiple Signaling and Tumor Progression and Metastasis. Mediators Inflamm 2020; 2020:9578701. [PMID: 32848510 PMCID: PMC7441421 DOI: 10.1155/2020/9578701] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 07/24/2020] [Indexed: 12/18/2022] Open
Abstract
Collagen triple helix repeat containing-1 (CTHRC1) has been identified as cancer-related protein. CTHRC1 expresses mainly in adventitial fibroblasts and neointimal smooth muscle cells of balloon-injured vessels and promotes cell migration and tissue repair in response to injury. CTHRC1 plays a pivotal role in some pathophysiological processes, including increasing bone mass, preventing myelination, and reversing collagen synthesis in many tumor cells. The ascended expression of CTHRC1 is related to tumorigenesis, proliferation, invasion, and metastasis in various human malignancies, including gastric cancer, pancreatic cancer, hepatocellular carcinoma, keloid, breast cancer, colorectal cancer, epithelial ovarian cancer, esophageal squamous cell carcinoma, cervical cancer, non-small-cell lung carcinoma, and melanoma. And molecules that regulate the expression of CTHRC1 include miRNAs, lncRNAs, WAIF1, and DPAGT1. Many reports have pointed that CTHRC1 could exert different effects through several signaling pathways such as TGF-β, Wnt, integrin β/FAK, Src/FAK, MEK/ERK, PI3K/AKT/ERK, HIF-1α, and PKC-δ/ERK signaling pathways. As a participant in tissue remodeling or immune response, CTHRC1 may promote early-stage cancer. Several recent studies have identified CTHRC1 as an effectual prognostic biomarker for predicting tumor recurrence or metastasis. It is worth noting that CTHRC1 has different cellular localization and mechanisms of action in different cells and different microenvironments. In this article, we focus on the advances in the signaling pathways mediated by CTHRC1 in tumors.
Collapse
|
7
|
Hodakoski C, Hopkins BD, Zhang G, Su T, Cheng Z, Morris R, Rhee KY, Goncalves MD, Cantley LC. Rac-Mediated Macropinocytosis of Extracellular Protein Promotes Glucose Independence in Non-Small Cell Lung Cancer. Cancers (Basel) 2019; 11:cancers11010037. [PMID: 30609754 PMCID: PMC6356657 DOI: 10.3390/cancers11010037] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 12/23/2018] [Accepted: 12/28/2018] [Indexed: 12/31/2022] Open
Abstract
Cancer cells can adapt to nutrient poor conditions by rewiring their metabolism and using alternate fuel sources. Identifying these adaptive metabolic pathways may provide novel targets for cancer therapy. Here, we identify a subset of non-small cell lung cancer (NSCLC) cell lines that survive in the absence of glucose by internalizing and metabolizing extracellular protein via macropinocytosis. Macropinocytosis is increased in these glucose independent cells, and is regulated by phosphoinositide 3-kinase (PI3K) activation of Rac-Pak signaling. Furthermore, inhibition of Rac-dependent macropinocytosis blocks glucose-independent proliferation. We find that degradation of internalized protein produces amino acids, including alanine, which generates TCA cycle and glycolytic intermediates in the absence of glucose. In this process, the conversion of alanine to pyruvate by alanine transaminase 2 (ALT2) is critical for survival during glucose starvation. Collectively, Rac driven macropinocytosis of extracellular protein is an adaptive metabolic pathway used by a subset of lung cancers to survive states of glucose deprivation, and may serve as a potential drug target for cancer therapy.
Collapse
Affiliation(s)
- Cindy Hodakoski
- Meyer Cancer Center, Weill Cornell Medicine-New York Presbyterian Hospital, New York, NY 10021, USA.
| | - Benjamin D Hopkins
- Meyer Cancer Center, Weill Cornell Medicine-New York Presbyterian Hospital, New York, NY 10021, USA.
| | - Guoan Zhang
- Proteomics and Metabolomics Core Facility, Weill Cornell Medicine, New York, NY 10021, USA.
| | - Taojunfeng Su
- Proteomics and Metabolomics Core Facility, Weill Cornell Medicine, New York, NY 10021, USA.
| | - Zhe Cheng
- Proteomics and Metabolomics Core Facility, Weill Cornell Medicine, New York, NY 10021, USA.
| | - Roxanne Morris
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medicine, 1300 York Ave A-421, New York, NY 10065, USA.
| | - Kyu Y Rhee
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medicine, 1300 York Ave A-421, New York, NY 10065, USA.
| | - Marcus D Goncalves
- Meyer Cancer Center, Weill Cornell Medicine-New York Presbyterian Hospital, New York, NY 10021, USA.
- Division of Endocrinology, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA.
| | - Lewis C Cantley
- Meyer Cancer Center, Weill Cornell Medicine-New York Presbyterian Hospital, New York, NY 10021, USA.
| |
Collapse
|
8
|
Porter AP, Papaioannou A, Malliri A. Deregulation of Rho GTPases in cancer. Small GTPases 2016; 7:123-38. [PMID: 27104658 PMCID: PMC5003542 DOI: 10.1080/21541248.2016.1173767] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 03/18/2016] [Accepted: 03/28/2016] [Indexed: 12/28/2022] Open
Abstract
In vitro and in vivo studies and evidence from human tumors have long implicated Rho GTPase signaling in the formation and dissemination of a range of cancers. Recently next generation sequencing has identified direct mutations of Rho GTPases in human cancers. Moreover, the effects of ablating genes encoding Rho GTPases and their regulators in mouse models, or through pharmacological inhibition, strongly suggests that targeting Rho GTPase signaling could constitute an effective treatment. In this review we will explore the various ways in which Rho signaling can be deregulated in human cancers.
Collapse
Affiliation(s)
- Andrew P. Porter
- Cell Signaling Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, UK
| | - Alexandra Papaioannou
- Cell Signaling Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, UK
- “Cellular and Genetic Etiology, Diagnosis and Treatment of Human Disease” Graduate Program, Medical School, University of Crete, Heraklion, Greece
| | - Angeliki Malliri
- Cell Signaling Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, UK
| |
Collapse
|
9
|
Orgaz JL, Herraiz C, Sanz-Moreno V. Rho GTPases modulate malignant transformation of tumor cells. Small GTPases 2014; 5:e29019. [PMID: 25036871 DOI: 10.4161/sgtp.29019] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Rho GTPases are involved in the acquisition of all the hallmarks of cancer, which comprise 6 biological capabilities acquired during the development of human tumors. The hallmarks include proliferative signaling, evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis programs, as defined by Hanahan and Weinberg. (1) Controlling these hallmarks are genome instability and inflammation. Emerging hallmarks are reprogramming of energy metabolism and evading immune destruction. To give a different view to the readers, we will not be focusing on invasion, metastasis, or cytoskeletal remodeling, but we will review here how Rho GTPases contribute to other hallmarks of cancer with a special emphasis on malignant transformation.
Collapse
Affiliation(s)
- Jose L Orgaz
- Randall Division of Cell and Molecular Biophysics; New Hunt's House; Guy's Campus; King's College London; London, UK
| | - Cecilia Herraiz
- Randall Division of Cell and Molecular Biophysics; New Hunt's House; Guy's Campus; King's College London; London, UK
| | - Victoria Sanz-Moreno
- Randall Division of Cell and Molecular Biophysics; New Hunt's House; Guy's Campus; King's College London; London, UK
| |
Collapse
|
10
|
Wang H, Han M, Whetsell W, Wang J, Rich J, Hallahan D, Han Z. Tax-interacting protein 1 coordinates the spatiotemporal activation of Rho GTPases and regulates the infiltrative growth of human glioblastoma. Oncogene 2013; 33:1558-69. [PMID: 23563176 PMCID: PMC3965267 DOI: 10.1038/onc.2013.97] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 01/17/2013] [Accepted: 02/04/2013] [Indexed: 12/28/2022]
Abstract
PDZ domains represent one group of the major structural units that mediate protein interactions in intercellular contact, signal transduction and assembly of biological machineries. TIP-1 protein is composed of a single PDZ domain that distinguishes TIP-1 from other PDZ domain proteins that more often contain multiple protein domains and function as scaffolds for protein complex assembly. However, the biological functions of TIP-1, especially in cell transformation and tumor progression, are still controversial as observed in a variety of cell types. In this study, we have identified ARHGEF7, a guanine nucleotide exchange factor (GEF) for Rho GTPases, as one novel TIP-1 interacting protein in human glioblastoma cells. We found that the presence of TIP-1 protein is essential to the intracellular redistribution of ARHGEF7 and rhotekin, one Rho effector, and the spatiotemporally coordinated activation of Rho GTPases (RhoA, Cdc42 and Rac1) in migrating glioblastoma cells. TIP-1 knockdown resulted in both aberrant localization of ARHGEF7 and rhotekin, as well as abnormal activation of Rho GTPases that was accompanied with impaired motility of glioblastoma cells. Furthermore, TIP-1 knockdown suppressed tumor cell dispersal in orthotopic glioblastoma murine models. We also observed high levels of TIP-1 expression in human glioblastoma specimens, and the elevated TIP-1 levels are associated with advanced staging and poor prognosis in glioma patients. Although more studies are needed to further dissect the mechanism(s) by which TIP-1 modulates the intracellular redistribution and activation of Rho GTPases, this study suggests that TIP-1 holds potential as both a prognostic biomarker and a therapeutic target of malignant gliomas.
Collapse
Affiliation(s)
- H Wang
- 1] Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, TN, USA [2] Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - M Han
- 1] Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, TN, USA [2] Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Science, Kunming, China [3] Graduate School, Chinese Academy of Sciences, Beijing, China
| | - W Whetsell
- Department of Pathology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - J Wang
- 1] Department of Neurological Surgery, Vanderbilt University School of Medicine, Nashville, TN, USA [2] Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - J Rich
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - D Hallahan
- Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO, USA
| | - Z Han
- 1] Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, TN, USA [2] Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN, USA [3] Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| |
Collapse
|
11
|
Abstract
RhoGTPases are defined as a family of 20 small G proteins playing important roles in almost every cellular process. RhoGTPases are guanine nucleotide-binding proteins existing in two forms: the active form which is GTP bound and the inactive one that being GDP bound. RhoGTPase-activating proteins known as RhoGAPs constitute one of the major classes of regulators of RhoGTPases. They act as negative regulators of the RhoGTPases by enhancing their slow intrinsic GTPase activity. STARD13, a GTPase activating protein (GAP) for RhoGTPases, has been described as a tumor suppressor in hepatocellular carcinoma. In the present review, we discuss the family of RhoGTPases, their regulation and their RhoGAPs, focusing mainly on STARD13.
Collapse
Affiliation(s)
- Sally El-Sitt
- Department of Natural Sciences, Lebanese American University, Beirut Campus, Beirut, Lebanon
| | | |
Collapse
|
12
|
Rho GTPases in primary brain tumor malignancy and invasion. J Neurooncol 2012; 108:333-9. [PMID: 22528793 DOI: 10.1007/s11060-012-0866-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 03/29/2012] [Indexed: 10/28/2022]
Abstract
Gliomas are the most common type of malignant primary brain tumor in humans, accounting for 80 % of malignant cases. Expression and activity of Rho GTPases, which coordinate several cellular processes including cell-cycle progression and cell migration, are commonly altered in many types of primary brain tumor. Here we review the suggested effects of deregulated Rho GTPase signaling on brain tumor malignancy, highlighting the controversy in the field. For instance, whereas expression of RhoA and RhoB has been found to be significantly reduced in astrocytic tumors, other studies have reported Rho-dependent LPA-induced migration in glioma cells. Moreover, whereas the Rac1 expression level has been found to be reduced in astrocytic tumor, it was overexpressed and induced invasion in medulloblastoma tumors. In addition to the Rho GTPases themselves, several of their downstream effectors (including ROCK, mDia, and N-WASP) and upstream regulators (including GEFs, GAPs, PI3K, and PTEN) have also been implicated in primary brain tumors.
Collapse
|
13
|
Yoon CH, Hyun KH, Kim RK, Lee H, Lim EJ, Chung HY, An S, Park MJ, Suh Y, Kim MJ, Lee SJ. The small GTPase Rac1 is involved in the maintenance of stemness and malignancies in glioma stem-like cells. FEBS Lett 2011; 585:2331-8. [PMID: 21704033 DOI: 10.1016/j.febslet.2011.05.070] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 05/07/2011] [Accepted: 05/26/2011] [Indexed: 10/18/2022]
Abstract
A subpopulation of cancer cells with stem cell properties is responsible for tumor formation, maintenance, and malignant progression; however, the molecular mechanisms underlying the maintenance of cancer stem-like cell properties have remained unclear. Here, we show that the Rho family GTPase Rac1 is involved in the glioma stem-like cell (GSLC) maintenance and tumorigenicity in human glioma. The Rac1-Pak signaling was markedly activated in GSLCs. Knockdown of Rac1 caused reduction of expression of GSLC markers, self-renewal-related proteins and neurosphere formation. Moreover, down-regulation of Rac1 suppressed the migration, invasion, and malignant transformation in GSLCs. Furthermore, inhibition of Rac1 enhanced radiation sensitivity of GSLCs. These results indicate that the small GTPase Rac1 is involved in the maintenance of stemness and malignancies in GSLCs.
Collapse
Affiliation(s)
- Chang-Hwan Yoon
- Department of Chemistry, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Tervonen TA, Partanen JI, Saarikoski ST, Myllynen M, Marques E, Paasonen K, Moilanen A, Wohlfahrt G, Kovanen PE, Klefstrom J. Faulty epithelial polarity genes and cancer. Adv Cancer Res 2011; 111:97-161. [PMID: 21704831 DOI: 10.1016/b978-0-12-385524-4.00003-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Epithelial architecture is formed in tissues and organs when groups of epithelial cells are organized into polarized structures. The epithelial function and integrity as well as signaling across the epithelial layer is orchestrated by apical junctional complexes (AJCs), which are landmarks for PAR/CRUMBS and lateral SCRIB polarity modules and by dynamic interactions of the cells with underlying basement membrane (BM). These highly organized epithelial architectures are demolished in cancer. In all advanced epithelial cancers, malignant cells have lost polarity and connections to the basement membrane and they have become proliferative, motile, and invasive. Clearly, loss of epithelial integrity associates with tumor progression but does it contribute to tumor development? Evidence from studies in Drosophila and recently also in vertebrate models have suggested that even the oncogene-driven enforced cell proliferation can be conditional, dependant on the influence of cell-cell or cell-microenvironment contacts. Therefore, loss of epithelial integrity may not only be an obligate consequence of unscheduled proliferation of malignant cells but instead, malignant epithelial cells may need to acquire capacity to break free from the constraints of integrity to freely and autonomously proliferate. We discuss how epithelial polarity complexes form and regulate epithelial integrity, highlighting the roles of enzymes Rho GTPases, aPKCs, PI3K, and type II transmembrane serine proteases (TTSPs). We also discuss relevance of these pathways to cancer in light of genetic alterations found in human cancers and review molecular pathways and potential pharmacological strategies to revert or selectively eradicate disorganized tumor epithelium.
Collapse
|
15
|
Vega FM, Ridley AJ. Rho GTPases in cancer cell biology. FEBS Lett 2008; 582:2093-101. [PMID: 18460342 DOI: 10.1016/j.febslet.2008.04.039] [Citation(s) in RCA: 597] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 04/22/2008] [Indexed: 12/18/2022]
Abstract
Rho GTPases contribute to multiple cellular processes that could affect cancer progression, including cytoskeletal dynamics, cell cycle progression, transcriptional regulation, cell survival and vesicle trafficking. In vitro several Rho GTPases have oncogenic activity and/or can promote cancer cell invasion, and this correlates with increased expression and activity in a variety of cancers. Conversely, other family members appear to act as tumour suppressors and are deleted, mutated or downregulated in some cancers. Genetic models are starting to provide new information on how Rho GTPases affect cancer development and progression. Here, we discuss how Rho GTPases could contribute to different steps of cancer progression, including proliferation, survival, invasion and metastasis.
Collapse
Affiliation(s)
- Francisco M Vega
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK.
| | | |
Collapse
|
16
|
Gómez del Pulgar T, Benitah SA, Valerón PF, Espina C, Lacal JC. Rho GTPase expression in tumourigenesis: evidence for a significant link. Bioessays 2005; 27:602-13. [PMID: 15892119 DOI: 10.1002/bies.20238] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Rho proteins belong to the small GTPases superfamily. They function as molecular switches that, in response to diverse stimuli, control key signaling and structural aspects of the cell. Although early studies proposed a role for Rho GTPases in cellular transformation, this effect was underestimated due to the fact that no genetic mutations affecting Rho-encoding genes were found in tumors. Recently, it has become evident that Rho GTPases participate in the carcinogenic process by either overexpression of some of the members of the family with oncogenic activity, downmodulation of other members with suggested tumor suppressor activity, or by alteration of upstream modulators or downstream effectors. Thus, alteration of the levels of expression of different members of the family of Rho GTPases has been detected in many types of human tumors leading to a great interest in the cellular effects elicited by these oncoproteins. This essay reviews the current evidence of dysregulation of Rho signaling by overexpression in human tumors.
Collapse
Affiliation(s)
- Teresa Gómez del Pulgar
- Instituto de Investigaciones Biomédicas, Translational Oncology Unit, CSIC-UAM-La Paz, Madrid, Spain
| | | | | | | | | |
Collapse
|
17
|
Hwang SL, Chang JH, Cheng CY, Howng SL, Sy WD, Lieu AS, Lin CL, Lee KS, Hong YR. The expression of rac1 pseudogene in human tissues and in human brain tumors. Eur Surg Res 2005; 37:100-4. [PMID: 15905615 DOI: 10.1159/000084540] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2004] [Accepted: 10/12/2004] [Indexed: 01/20/2023]
Abstract
BACKGROUND Recent studies have demonstrated that Rac is a regulator of cell morphology and growth. Rac1 gene appears to have involvement in tumorigenesis and metastatic potential. In our previous study of rac1 gene in 45 human brain tumors, rac1 pseudogene was found. The rac1 pseudogene is an intronless pseudogene and has a similarity of 86% with rac1 nucleotide sequence. The rac1 pseudogene contains 579 nucleotides and only 46 amino acids can be translated. Little is known about the expression of rac1 pseudogene in human tissues or tumors. MATERIALS AND METHODS The expression of rac1 gene and rac1 pseudogene in different human tissues and brain tumors was investigated by the use of reverse transcriptase-polymerase chain reaction and Northern blotting. RESULTS The rac1 gene is apparently expressed in these 8 human tissues. The rac1 pseudogene is also apparently expressed in human tissues except for brain tissue. The overexpression of rac1 gene in brain tumors was 8% (2/25) and the overexpression of rac1 pseudogene was 76.9% (20/26). Only two astrocytomas had overexpression of rac1 gene, compared with normal brain tissues. The overexpression of rac1 pseudogene was 6 of 9 in meningiomas, 7 of 9 in astrocytomas, and 7 of 8 in pituitary adenomas. CONCLUSIONS High frequency of overexpression of rac1 pseudogene was detected in the human brain tumors when compared with that expressed in the normal brain tissues. Our study suggested that the rac1 pseudogene may play an important role of the tumorigenesis of brain.
Collapse
Affiliation(s)
- S L Hwang
- Division of Neurosurgery, Kaohsiung Medical University, Kaohsiung, Taiwan
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Abstract
PURPOSE OF REVIEW Conventional surgery, radio- and chemotherapy have failed to significantly improve the prognosis of patients with malignant astrocytomas--hence the need for understanding their molecular biology. Harvesting this understanding to yield novel biological targeted therapies has approached the clinical doorstep. Therapeutic efficacy will likely require combinatorial therapy involving biologicals and conventional therapies, with small incremental efficacy in selected sub-groups. This review highlights some of the findings over the past year (June 2003-2004) that have contributed to this slow but essential journey towards our understanding of the biology of astrocytomas. RECENT FINDINGS The accumulation of loss and/or gain of function molecular alterations underlying astrocytoma formation, progression and key growth parameters including proliferation, angiogenesis, apoptosis, invasion and resistance are emerging. These alterations involve those regulating the growth factor/receptor and downstream signaling networks, cell cycle, immune modulators and other key biological processes. The advances are facilitated by interactions amongst clinician and basic scientists, in both academia and industry. They have incorporated high-throughput bioinformatics analysis of genomic and expression array data, the emerging field of proteomics and development of various genetically engineered models of astrocytomas. SUMMARY Astrocytomas, like other cancers, are a result of several molecular alterations, some of which strongly correlate to their pathological grade. However, molecular heterogeneity exists between astrocytomas of similar grades and likely between varying micro-environmental regions of a single tumor. Characterization of the molecular signature of an astrocytoma and linking with the appropriate 'tailored' therapie(s) is the hope of the future.
Collapse
Affiliation(s)
- Abhijit Guha
- Western Hospital, University of Toronto, Toronto, Ontario M5T 2S8, Canada.
| | | |
Collapse
|