1
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Li L, Xu Q, Tang C. RGS proteins and their roles in cancer: friend or foe? Cancer Cell Int 2023; 23:81. [PMID: 37118788 PMCID: PMC10148553 DOI: 10.1186/s12935-023-02932-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/21/2023] [Indexed: 04/30/2023] Open
Abstract
As negative modulators of G-protein-coupled receptors (GPCRs) signaling, regulators of G protein signaling (RGS) proteins facilitate various downstream cellular signalings through regulating kinds of heterotrimeric G proteins by stimulating the guanosine triphosphatase (GTPase) activity of G-protein α (Gα) subunits. The expression of RGS proteins is dynamically and precisely mediated by several different mechanisms including epigenetic regulation, transcriptional regulation -and post-translational regulation. Emerging evidence has shown that RGS proteins act as important mediators in controlling essential cellular processes including cell proliferation, survival -and death via regulating downstream cellular signaling activities, indicating that RGS proteins are fundamentally involved in sustaining normal physiological functions and dysregulation of RGS proteins (such as aberrant expression of RGS proteins) is closely associated with pathologies of many diseases such as cancer. In this review, we summarize the molecular mechanisms governing the expression of RGS proteins, and further discuss the relationship of RGS proteins and cancer.
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Affiliation(s)
- Lin Li
- National Clinical Research Center for Child Health of the Children's Hospital, Zhejiang University School of Medicine, No. 3333, Binsheng Rd., Hangzhou, 310052, People's Republic of China
- Department of Urology, Third Affiliated Hospital of the Second Military Medical University, Shanghai, 201805, China
| | - Qiang Xu
- National Clinical Research Center for Child Health of the Children's Hospital, Zhejiang University School of Medicine, No. 3333, Binsheng Rd., Hangzhou, 310052, People's Republic of China
| | - Chao Tang
- National Clinical Research Center for Child Health of the Children's Hospital, Zhejiang University School of Medicine, No. 3333, Binsheng Rd., Hangzhou, 310052, People's Republic of China.
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2
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Tian M, Ma Y, Li T, Wu N, Li J, Jia H, Yan M, Wang W, Bian H, Tan X, Qi J. Functions of regulators of G protein signaling 16 in immunity, inflammation, and other diseases. Front Mol Biosci 2022; 9:962321. [PMID: 36120550 PMCID: PMC9478547 DOI: 10.3389/fmolb.2022.962321] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Regulators of G protein signaling (RGS) act as guanosine triphosphatase activating proteins to accelerate guanosine triphosphate hydrolysis of the G protein α subunit, leading to the termination of the G protein-coupled receptor (GPCR) downstream signaling pathway. RGS16, which is expressed in a number of cells and tissues, belongs to one of the small B/R4 subfamilies of RGS proteins and consists of a conserved RGS structural domain with short, disordered amino- and carboxy-terminal extensions and an α-helix that classically binds and de-activates heterotrimeric G proteins. However, with the deepening of research, it has been revealed that RGS16 protein not only regulates the classical GPCR pathway, but also affects immune, inflammatory, tumor and metabolic processes through other signaling pathways including the mitogen-activated protein kinase, phosphoinositide 3-kinase/protein kinase B, Ras homolog family member A and stromal cell-derived factor 1/C-X-C motif chemokine receptor 4 pathways. Additionally, the RGS16 protein may be involved in the Hepatitis B Virus -induced inflammatory response. Therefore, given the continuous expansion of knowledge regarding its role and mechanism, the structure, characteristics, regulatory mechanisms and known functions of the small RGS proteinRGS16 are reviewed in this paper to prepare for diagnosis, treatment, and prognostic evaluation of different diseases such as inflammation, tumor, and metabolic disorders and to better study its function in other diseases.
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Affiliation(s)
- Miaomiao Tian
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Yan Ma
- Zibo Central Hospital, Zibo, China
| | - Tao Li
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Nijin Wu
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Jiaqi Li
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Huimin Jia
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Meizhu Yan
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Wenwen Wang
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Hongjun Bian
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Xu Tan
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- *Correspondence: Jianni Qi, ; Xu Tan,
| | - Jianni Qi
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China
- *Correspondence: Jianni Qi, ; Xu Tan,
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3
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Jiang L, Shen J, Zhang N, He Y, Wan Z. Association of RGS20 expression with the progression and prognosis of renal cell carcinoma. Oncol Lett 2021; 22:643. [PMID: 34386065 PMCID: PMC8299006 DOI: 10.3892/ol.2021.12904] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 04/28/2021] [Indexed: 12/29/2022] Open
Abstract
Regulator of G protein signaling 20 (RGS20) has been shown to be highly expressed in various types of cancer. The present study aimed to investigate the effects of RGS20 in patients with renal cell carcinoma (RCC) and in RCC cells. Bioinformatics analysis was performed to analyze the role of RGS20 in RCC. Quantitative PCR and western blotting were used to determine the mRNA and protein expression levels of RGS20 in cells, respectively. After RGS20 inhibition, the proliferation, apoptosis, migration and invasiveness of A-498 cells were tested using MTT assay, EdU assay, propidium iodide staining, Annexin V-FITC/PI kit, wound healing assay and Transwell assay. High RGS20 expression was closely associated with the progression and immune infiltration of RCC, and may be considered as an independent indicator of poor prognosis in RCC. After knocking down RGS20, the proliferation, migration and invasiveness of cells were impaired, the cell cycle was arrested at the G0/G1 phase, and the level of apoptosis was increased. In addition, the mRNA expression levels of securin, CDC20 and cyclin B1 were decreased in RGS20-knockdown cells. RGS20 expression was significantly associated with the infiltration level of activated CD4 T cells, type 1 T helper cells and activated dendritic cells. In summary, RGS20 expression was associated with RCC progression and poor prognosis; thus, it may be used to estimate the prognosis of RCC and may serve as a new potential treatment strategy for RCC.
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Affiliation(s)
- Lin Jiang
- Department of Urology, Caoxian People's Hospital, Heze, Shandong 274400, P.R. China
| | - Jiangwei Shen
- Department of Urology, Caoxian People's Hospital, Heze, Shandong 274400, P.R. China
| | - Ning Zhang
- Department of Urology, Caoxian People's Hospital, Heze, Shandong 274400, P.R. China
| | - Yongchao He
- Department of Urology, Caoxian People's Hospital, Heze, Shandong 274400, P.R. China
| | - Zhenghua Wan
- Department of Urology, The Fifth Hospital of Xiamen, Xiamen, Fujian 361101, P.R. China
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Leysen H, van Gastel J, Hendrickx JO, Santos-Otte P, Martin B, Maudsley S. G Protein-Coupled Receptor Systems as Crucial Regulators of DNA Damage Response Processes. Int J Mol Sci 2018; 19:E2919. [PMID: 30261591 PMCID: PMC6213947 DOI: 10.3390/ijms19102919] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/14/2018] [Accepted: 09/15/2018] [Indexed: 12/11/2022] Open
Abstract
G protein-coupled receptors (GPCRs) and their associated proteins represent one of the most diverse cellular signaling systems involved in both physiological and pathophysiological processes. Aging represents perhaps the most complex biological process in humans and involves a progressive degradation of systemic integrity and physiological resilience. This is in part mediated by age-related aberrations in energy metabolism, mitochondrial function, protein folding and sorting, inflammatory activity and genomic stability. Indeed, an increased rate of unrepaired DNA damage is considered to be one of the 'hallmarks' of aging. Over the last two decades our appreciation of the complexity of GPCR signaling systems has expanded their functional signaling repertoire. One such example of this is the incipient role of GPCRs and GPCR-interacting proteins in DNA damage and repair mechanisms. Emerging data now suggest that GPCRs could function as stress sensors for intracellular damage, e.g., oxidative stress. Given this role of GPCRs in the DNA damage response process, coupled to the effective history of drug targeting of these receptors, this suggests that one important future activity of GPCR therapeutics is the rational control of DNA damage repair systems.
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Affiliation(s)
- Hanne Leysen
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
| | - Jaana van Gastel
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
- Translational Neurobiology Group, Center of Molecular Neurology, VIB, 2610 Antwerp, Belgium.
| | - Jhana O Hendrickx
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
- Translational Neurobiology Group, Center of Molecular Neurology, VIB, 2610 Antwerp, Belgium.
| | - Paula Santos-Otte
- Institute of Biophysics, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| | - Bronwen Martin
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
| | - Stuart Maudsley
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
- Translational Neurobiology Group, Center of Molecular Neurology, VIB, 2610 Antwerp, Belgium.
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Alqinyah M, Hooks SB. Regulating the regulators: Epigenetic, transcriptional, and post-translational regulation of RGS proteins. Cell Signal 2017; 42:77-87. [PMID: 29042285 DOI: 10.1016/j.cellsig.2017.10.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/06/2017] [Accepted: 10/13/2017] [Indexed: 12/11/2022]
Abstract
Regulators of G protein signaling (RGS) are a family of proteins classically known to accelerate the intrinsic GTPase activity of G proteins, which results in accelerated inactivation of heterotrimeric G proteins and inhibition of G protein coupled receptor signaling. RGS proteins play major roles in essential cellular processes, and dysregulation of RGS protein expression is implicated in multiple diseases, including cancer, cardiovascular and neurodegenerative diseases. The expression of RGS proteins is highly dynamic and is regulated by epigenetic, transcriptional and post-translational mechanisms. This review summarizes studies that report dysregulation of RGS protein expression in disease states, and presents examples of drugs that regulate RGS protein expression. Additionally, this review discusses, in detail, the transcriptional and post-transcriptional mechanisms regulating RGS protein expression, and further assesses the therapeutic potential of targeting these mechanisms. Understanding the molecular mechanisms controlling the expression of RGS proteins is essential for the development of therapeutics that indirectly modulate G protein signaling by regulating expression of RGS proteins.
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Affiliation(s)
- Mohammed Alqinyah
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, USA
| | - Shelley B Hooks
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, USA.
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Li Q, Jin W, Cai Y, Yang F, Chen E, Ye D, Wang Q, Guan X. Regulator of G protein signaling 20 correlates with clinicopathological features and prognosis in triple-negative breast cancer. Biochem Biophys Res Commun 2017; 485:693-697. [PMID: 28237701 DOI: 10.1016/j.bbrc.2017.02.106] [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] [Received: 02/03/2017] [Accepted: 02/20/2017] [Indexed: 12/20/2022]
Abstract
Triple-negative breast cancer (TNBC) is a highly aggressive tumor subtype lacking effective prognostic indicators or therapeutic targets. Therefore, finding a novel molecular biomarker for TNBC to achieve target therapy and predict its prognosis is crucial in preventing inappropriate treatment. Regulator of G-protein signaling (RGS) families of protein can negatively regulate signaling of heterotrimeric G proteins and are known to be upregulated in various tumors. In this study, we demonstrated that RGS20 was more highly expressed in TNBC tumor tissue than in adjacent normal tissue by analyzing the cancer genome atlas (TCGA) database. However, RGS20 expression was low in all breast cancer and luminal breast cancer patients. Validated by the TCGA cohort, RGS20 was upregulated in lymph node-positive TNBC compared with that in lymph node-negative breast cancer. High expression of RGS20 had a risk of lymph node metastasis, ki-67 > 14%, poor N stage, and poor clinical stage in the immunohistochemistry of tissue microarrays. Moreover, K-M plot analysis showed that TNBC patients with high RGS20 expression had poor relapse-free survival. In summary, the findings revealed that RGS20 was a special TNBC oncogene that promoted tumor progression and influenced TNBC prognosis. This study is the first to show that RGS20 was a special oncogene, and its high expression was significantly associated with the progression and prognosis of TNBC. RGS20 may be a novel molecular biomarker for the targeted therapy and prognosis of TNBC.
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Affiliation(s)
- Quan Li
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Southern Medical University, Guangzhou, 510282, China; Department of Oncological Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Wenxu Jin
- Department of Oncological Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Yefeng Cai
- Department of Oncological Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Fang Yang
- Department of Medical Oncology, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China
| | - Endong Chen
- Department of Oncological Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Danrong Ye
- Department of Oncological Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Qingxuan Wang
- Department of Oncological Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Xiaoxiang Guan
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Southern Medical University, Guangzhou, 510282, China; Department of Medical Oncology, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China.
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7
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Hoshi Y, Endo K, Shirakihara T, Fukagawa A, Miyazawa K, Saitoh M. The potential role of regulator of G-protein signaling 16 in cell motility mediated by δEF1 family proteins. FEBS Lett 2016; 590:270-8. [PMID: 26823172 PMCID: PMC4819697 DOI: 10.1002/1873-3468.12042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 12/02/2015] [Accepted: 12/09/2015] [Indexed: 01/09/2023]
Abstract
The epithelial–mesenchymal transition (EMT) is associated with tumor progression. We reported previously that expression of the δEF1 family proteins (δEF1/ZEB1 and SIP1/ZEB2), key regulators of the EMT, is positively correlated with EMT phenotypes and aggressiveness of breast cancer. Here, we show that the expression levels of regulator of G‐protein signaling 16 (RGS16) are negatively correlated with those of the δEF1 family proteins. On the basis of the results of gain‐ and loss‐of‐function analyses, we suggest that δEF1 family proteins promote cell motility of breast cancer cells directly or indirectly through repressing expression of RGS16.
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Affiliation(s)
- Yuta Hoshi
- Research Training Program for Undergraduates, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan.,Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Kaori Endo
- Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Takuya Shirakihara
- Division of Metastasis & Invasion Signaling, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan
| | - Akihiko Fukagawa
- Research Training Program for Undergraduates, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan.,Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Keiji Miyazawa
- Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Masao Saitoh
- Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan.,Center for Medical Education and Sciences, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
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Li Y, Li L, Lin J, Hu X, Li B, Xue A, Shen Y, Jiang J, Zhang M, Xie J, Zhao Z. Deregulation of RGS17 Expression Promotes Breast Cancer Progression. J Cancer 2015; 6:767-75. [PMID: 26185539 PMCID: PMC4504113 DOI: 10.7150/jca.11833] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 06/03/2015] [Indexed: 12/14/2022] Open
Abstract
Objective: A high level of RGS17 expression is observed in diverse human cancers and correlates with tumor progression. Herein, we aim to investigate its expression and function in breast cancer. Methods: The expression of RGS17 was detected by immunohistochemical analysis and western blot analysis. The level of miR-32 expression was investigated by qRT-PCR. Western blot analysis was used to determine the relationship between RGS17 and miR-32. A series of loss or gain of function assays was performed to measure the effects of RGS17 or miR-32 on tumor migration, invasion, and proliferation. Results: Compared to that in normal breast specimen, the expression of RGS17 had a significantly higher expression level in breast cancer tissues and cell lines. Although the potential relationship of RGS17 expression with clinicopathological features was not observed, there was a significant correlation of RGS17 expression with p63 expression. In cells, inhibition of RGS17 expression impaired cell migration, invasion, and proliferation. Further, RGS17 was identified as a direct and functional target of miR-32. Overexpression of miR-32 in cells could decrease the expression of RGS17 and inhibit cell migration, invasion, and proliferation. In contrast, ectopic expression of RGS17 could attenuate phenotypes caused by miR-32 overexpression. Conclusion: The expression of RGS17 was upregulated in breast cancer, which could enhance cell migration, invasion, and proliferation. Moreover, the RGS17 was identified as a target of miR-32. Our results suggest that RGS17 might play an important role in breast cancer progression and could be a potential target for human breast cancer treatment.
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Affiliation(s)
- Yuhua Li
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Liliang Li
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Junyi Lin
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Xin Hu
- 2. Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Shanghai Cancer Center, Fudan University, Shanghai, 200032, China
| | - Beixu Li
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Aimin Xue
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Yiwen Shen
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Jieqing Jiang
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Mingchang Zhang
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Jianhui Xie
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Ziqin Zhao
- 1. Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
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Carper MB, Denvir J, Boskovic G, Primerano DA, Claudio PP. RGS16, a novel p53 and pRb cross-talk candidate inhibits migration and invasion of pancreatic cancer cells. Genes Cancer 2015; 5:420-35. [PMID: 25568667 PMCID: PMC4279439 DOI: 10.18632/genesandcancer.43] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 11/26/2014] [Indexed: 12/11/2022] Open
Abstract
Data collected since the discovery of p53 and pRb/RB1 suggests these tumor suppressors cooperate to inhibit tumor progression. Patients who have mutations in both p53 and RB1 genes have increased tumor reoccurrence and decreased survival compared to patients with only one tumor suppressor gene inactivated. It remains unclear how p53 and pRb cooperate toward inhibiting tumorigenesis. Using RNA expression profiling we identified 179 p53 and pRb cross-talk candidates in normal lung fibroblasts (WI38) cells exogenously coexpressing p53 and pRb. Regulator of G protein signaling 16 (RGS16) was among the p53 and pRb cross-talk candidates and has been implicated in inhibiting activation of several oncogenic pathways associated with proliferation, migration, and invasion of cancer cells. RGS16 has been found to be downregulated in pancreatic cancer patients with metastases compared to patients without metastasis. Expression of RGS16 mRNA was decreased in the pancreatic cancer cell lines tested compared to control. Expression of RGS16 inhibited migration of the BxPC-3 and AsPC-1 but not PANC-1 cells and inhibited invasion of BxPC-3 and AsPC-1 cells with no impact on cell viability. We have identified for the first time p53 and pRb cross-talk candidates and a role for RGS16 to inhibit pancreatic cancer migration and invasion.
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Affiliation(s)
- Miranda B Carper
- McKown Translational Genomic Research Institute, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA ; Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA
| | - James Denvir
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA
| | - Goran Boskovic
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA
| | - Donald A Primerano
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA
| | - Pier Paolo Claudio
- McKown Translational Genomic Research Institute, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA ; Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA ; Department of Surgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA
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Suurväli J, Pahtma M, Saar R, Paalme V, Nutt A, Tiivel T, Saaremäe M, Fitting C, Cavaillon J, Rüütel Boudinot S. RGS16 Restricts the Pro-Inflammatory Response of Monocytes. Scand J Immunol 2014; 81:23-30. [DOI: 10.1111/sji.12250] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 09/26/2014] [Indexed: 02/02/2023]
Affiliation(s)
- J. Suurväli
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - M. Pahtma
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - R. Saar
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - V. Paalme
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - A. Nutt
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - T. Tiivel
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - M. Saaremäe
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
| | - C. Fitting
- Unité Cytokines & Inflammation; Institut Pasteur; Paris France
| | - J.M. Cavaillon
- Unité Cytokines & Inflammation; Institut Pasteur; Paris France
| | - S. Rüütel Boudinot
- Department of Gene Technology; Tallinn University of Technology; Tallinn Estonia
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Farahani E, Patra HK, Jangamreddy JR, Rashedi I, Kawalec M, Rao Pariti RK, Batakis P, Wiechec E. Cell adhesion molecules and their relation to (cancer) cell stemness. Carcinogenesis 2014; 35:747-59. [PMID: 24531939 DOI: 10.1093/carcin/bgu045] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Despite decades of search for anticancer drugs targeting solid tumors, this group of diseases remains largely incurable, especially if in advanced, metastatic stage. In this review, we draw comparison between reprogramming and carcinogenesis, as well as between stem cells (SCs) and cancer stem cells (CSCs), focusing on changing garniture of adhesion molecules. Furthermore, we elaborate on the role of adhesion molecules in the regulation of (cancer) SCs division (symmetric or asymmetric), and in evolving interactions between CSCs and extracellular matrix. Among other aspects, we analyze the role and changes of expression of key adhesion molecules as cancer progresses and metastases develop. Here, the role of cadherins, integrins, as well as selected transcription factors like Twist and Snail is highlighted, not only in the regulation of epithelial-to-mesenchymal transition but also in the avoidance of anoikis. Finally, we briefly discuss recent developments and new strategies targeting CSCs, which focus on adhesion molecules or targeting tumor vasculature.
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Affiliation(s)
- Ensieh Farahani
- Department of Clinical and Experimental Medicine, Division of Cell Biology and Integrative Regenerative Medicine Center (IGEN) and
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12
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Cieślar-Pobuda A, Łos MJ. Prospects and limitations of “Click-Chemistry”-based DNA labeling technique employing 5-ethynyl-2′deoxyuridine (EdU). Cytometry A 2013; 83:977-8. [DOI: 10.1002/cyto.a.22394] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 08/22/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Artur Cieślar-Pobuda
- Department Clinical and Experimental Medicine (IKE); Division of Cell Biology, and Integrative Regenerative Medicine Center (IGEN); Linköping University; Sweden
- Biosystems Group; Institute of Automatic Control; Silesian University of Technology; Gliwice Poland
| | - Marek J. Łos
- Department Clinical and Experimental Medicine (IKE); Division of Cell Biology, and Integrative Regenerative Medicine Center (IGEN); Linköping University; Sweden
- Department of Pathology; Pomeranian Medical University; Szczecin Poland
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13
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Chi C, Tian R, Liu H, Wang H, Wei J, Guo J, Guo F, Li S. Follow-up study of abnormal biological indicators and gene expression in the peripheral blood of three accidentally exposed persons. JOURNAL OF RADIATION RESEARCH 2013; 54:840-51. [PMID: 23559597 PMCID: PMC3766294 DOI: 10.1093/jrr/rrt022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 01/16/2013] [Accepted: 02/27/2013] [Indexed: 05/19/2023]
Abstract
In order to identify biomarkers for early diagnosis and/or for therapeutic targets in the delayed health effects of ionizing radiation, we analyzed the subgroups of lymphocytes, serum protein levels and gene expression profiles in the peripheral blood of three ⁶⁰Co γ-ray accidentally exposed persons during the three years after irradiation. Flow cytometry analyses and agarose gel electrophoresis were applied to investigate the subgroups of lymphocytes and the composition of serum proteins, respectively. Gene expression profiling was obtained using a whole genome gene expression chip assay. Both the percentage of CD4+ T lymphocytes and the ratio of Th to Ts were reduced compared with the normal control values. The percentage of albumin decreased whereas beta globulin increased. There were 285 up-regulated and 446 down-regulated genes in irradiated samples relative to the control samples. The expression of KDR, CEACAM8 and OSM was validated by RT-PCR. The majority of the differentially expressed genes encode proteins associated with the immune response, inflammation, oncogenesis, cell structure, oxidative stress, neuro-hormone regulation, reproduction, susceptibility to psychiatric disorders, or transcriptional regulation. We have identified a number of promising novel candidates that have potential for serving as biomarkers for delayed damage. Furthermore, the changes in the immunological indicator CD4+ T cells, and the ratio of CD4+ T to CD8+ T cells may be biomarkers for the prediction of delayed damage by ionizing radiation. The findings of our study are useful for forming a comprehensive understanding of the mechanisms underlying the delayed effects of ionizing radiation.
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Affiliation(s)
- Cuiping Chi
- Department of Radiation Medicine and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, 030006, China
- Corresponding author. Tel: +86-351-220-2218; Fax: +86-351-702-0407;
| | - Rong Tian
- Affiliated Hospital of China Institute for Radiation Protection
| | - Huifang Liu
- Shanxi Center for Disease Control and Prevention, Xiao Nan Guan Street No.8, Taiyuan, 030012, China
| | - Haiyan Wang
- Department of Radiation Medicine and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Jinping Wei
- Department of Radiation Medicine and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Jianping Guo
- Department of Radiation Medicine and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Fengling Guo
- Affiliated Hospital of China Institute for Radiation Protection
| | - Shufang Li
- Department of Radiation Medicine and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, 030006, China
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14
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Fagan RL, Cryderman DE, Kopelovich L, Wallrath LL, Brenner C. Laccaic acid A is a direct, DNA-competitive inhibitor of DNA methyltransferase 1. J Biol Chem 2013; 288:23858-67. [PMID: 23839987 DOI: 10.1074/jbc.m113.480517] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Methylation of cytosines in CpG dinucleotides is the predominant epigenetic mark on vertebrate DNA. DNA methylation is associated with transcriptional repression. The pattern of DNA methylation changes during development and with disease. Human DNA methyltransferase 1 (Dnmt1), a 1616-amino acid multidomain enzyme, is essential for maintenance of DNA methylation in proliferating cells and is considered an important cancer drug target. Using a fluorogenic, endonuclease-coupled DNA methylation assay with an activated form of Dnmt1 engineered to lack the replication foci targeting sequence domain, we discovered that laccaic acid A (LCA), a highly substituted anthraquinone natural product, is a direct inhibitor with a 310 nm Ki. LCA is competitive with the DNA substrate in in vitro methylation assays and alters the expression of methylated genes in MCF-7 breast cancer cells synergistically with 5-aza-2'-deoxycytidine. LCA represents a novel class of Dnmt-targeted molecular probes, with biochemical properties that allow it to distinguish between non DNA-bound and DNA-bound Dnmt1.
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Affiliation(s)
- Rebecca L Fagan
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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15
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Sethakorn N, Dulin NO. RGS expression in cancer: oncomining the cancer microarray data. J Recept Signal Transduct Res 2013; 33:166-71. [DOI: 10.3109/10799893.2013.773450] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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16
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Vasilatos SN, Katz TA, Oesterreich S, Wan Y, Davidson NE, Huang Y. Crosstalk between lysine-specific demethylase 1 (LSD1) and histone deacetylases mediates antineoplastic efficacy of HDAC inhibitors in human breast cancer cells. Carcinogenesis 2013; 34:1196-207. [PMID: 23354309 DOI: 10.1093/carcin/bgt033] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Our previous studies demonstrated that lysine-specific demethylase 1 (LSD1) and histone deacetylases (HDACs) closely interact in controlling growth of breast cancer cells. However, the underlying mechanisms are largely unknown. In this study, we showed that knockdown of LSD1 expression (LSD1-KD) by RNAi decreased mRNA levels of HDAC isozymes in triple-negative breast cancer (TNBC) cells. Small interfering RNA (siRNA)-mediated depletion of HDAC5 expression induced the most significant accumulation of H3K4me2, a specific substrate of LSD1. Combined treatment with LSD1 inhibitor, pargyline, and HDAC inhibitor, SAHA (Vorinostat), led to superior growth inhibition and apoptotic death in TNBC cells, but exhibited additive or antagonistic effect on growth inhibition in non-TNBC counterparts or non-tumorigenic breast cells. Additionally, LSD1-KD enhanced SAHA-induced reexpression of a subset of aberrantly silenced genes, such as NR4A1, PCDH1, RGS16, BIK, and E-cadherin whose reexpression may be tumor suppressive. Genome-wide microarray study in MDA-MB-231 cells identified a group of tumor suppressor genes whose expression was induced by SAHA and significantly enhanced by LSD1-KD. We also showed that concurrent depletion of RGS16 by siRNA reduced overall cytotoxicity of SAHA and blocked the reexpression of E-cadherin, CDKN1C and ING1 in LSD1-deficient MDA-MB-231 cells. Furthermore, cotreatment with RGS16 siRNA reversed the downregulation of nuclear factor-kappaB expression induced by combined inhibition of LSD1 and HDACs, suggesting a crucial role of RGS16 in controlling key pathways of cell death in response to combination therapy. Taken together, these results provide novel mechanistic insight into the breast cancer subtype-dependent role of LSD1 in mediating HDAC activity and therapeutic efficacy of HDAC inhibitor.
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Wiechec E, Overgaard J, Kjeldsen E, Hansen LL. Chromosome 1q25.3 copy number alterations in primary breast cancers detected by multiplex ligation-dependent probe amplification and allelic imbalance assays and its comparison with fluorescent in situ hybridization assays. Cell Oncol (Dordr) 2012; 36:113-20. [DOI: 10.1007/s13402-012-0117-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2012] [Indexed: 11/28/2022] Open
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18
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Wiechec E. Implications of genomic instability in the diagnosis and treatment of breast cancer. Expert Rev Mol Diagn 2011; 11:445-53. [PMID: 21545260 DOI: 10.1586/erm.11.21] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Tumorigenesis is a multistep process resulting from DNA mutations observed at the DNA sequence and chromosome level as well as epigenetic changes, which affect expression of oncogenes and tumor suppressor genes. Breast cancer is a very heterogeneous disease that manifests in various histological and clinical types. Defects in the biological action of the genome driven by various alterations, such as point mutations and chromosomal rearrangements, lead to the collapse of genome integrity, uncontrolled cell proliferation and failure in apoptotic cell death. Detailed profiling of breast cancer-associated genomic alterations is indispensable for the design of individualized anticancer therapy, by suggesting diagnostic and prognostic criteria as well as the outcome of applied treatment. Among various directions of cancer research, identification of genomic alterations in breast cancer and their translation into clinical applications is at the forefront.
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Affiliation(s)
- Emilia Wiechec
- Otto-von-Guericke University, Institute of Molecular and Clinical Immunology, Leipziger Str. 44, 39120 Magdeburg, Germany.
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19
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Dai J, Gu J, Lu C, Lin J, Stewart D, Chang D, Roth JA, Wu X. Genetic variations in the regulator of G-protein signaling genes are associated with survival in late-stage non-small cell lung cancer. PLoS One 2011; 6:e21120. [PMID: 21698121 PMCID: PMC3117866 DOI: 10.1371/journal.pone.0021120] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 05/19/2011] [Indexed: 01/08/2023] Open
Abstract
The regulator of G-protein signaling (RGS) pathway plays an important role in signaling transduction, cellular activities, and carcinogenesis. We hypothesized that genetic variations in RGS gene family may be associated with the response of late-stage non-small cell lung cancer (NSCLC) patients to chemotherapy or chemoradiotherapy. We selected 95 tagging single nucleotide polymorphisms (SNPs) in 17 RGS genes and genotyped them in 598 late-stage NSCLC patients. Thirteen SNPs were significantly associated with overall survival. Among them, rs2749786 of RGS12 was most significant. Stratified analysis by chemotherapy or chemoradiation further identified SNPs that were associated with overall survival in subgroups. Rs2816312 of RGS1 and rs6689169 of RGS7 were most significant in chemotherapy group and chemoradiotherapy group, respectively. A significant cumulative effect was observed when these SNPs were combined. Survival tree analyses identified potential interactions between rs944343, rs2816312, and rs1122794 in affecting survival time in patients treated with chemotherapy, while the genotype of rs6429264 affected survival in chemoradiation-treated patients. To our knowledge, this is the first study to reveal the importance of RGS gene family in the survival of late-stage NSCLC patients.
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Affiliation(s)
- Jingyao Dai
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Jian Gu
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Charles Lu
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Jie Lin
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - David Stewart
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - David Chang
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Jack A. Roth
- Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Xifeng Wu
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- * E-mail:
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20
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Wiechec E, Wiuf C, Overgaard J, Hansen LL. High-Resolution Melting Analysis for Mutation Screening of RGSL1, RGS16, and RGS8 in Breast Cancer. Cancer Epidemiol Biomarkers Prev 2010; 20:397-407. [DOI: 10.1158/1055-9965.epi-10-0514] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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21
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Tesmer JJG. Structure and function of regulator of G protein signaling homology domains. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2009; 86:75-113. [PMID: 20374714 DOI: 10.1016/s1877-1173(09)86004-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
All regulator of G protein signaling (RGS) proteins contain a conserved domain of approximately 130 amino acids that binds to activated heterotrimeric G protein α subunits (Gα) and accelerates their rate of GTP hydrolysis. Homologous domains are found in at least six other protein families, including a family of Rho guanine nucleotide exchange factors (RhoGEFs) and the G protein-coupled receptor kinases (GRKs). Although some of the RhoGEF and GRK RGS-like domains can also bind to activated Gα subunits, they do so in distinct ways and with much lower levels of GTPase activation. In other protein families, the domains have as of yet no obvious relationship to heterotrimeric G protein signaling. These RGS homology (RH) domains are now recognized as mediators of extraordinarily diverse protein-protein interactions. Through these interactions, they play roles that range from enzyme to molecular scaffold to signal transducing module. In this review, the atomic structures of RH domains from RGS proteins, Axins, RhoGEFs, and GRKs are compared in light of what is currently known about their functional roles.
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Affiliation(s)
- John J G Tesmer
- Department of Pharmacology, Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109‐2216, USA
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22
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Miyoshi N, Ishii H, Sekimoto M, Doki Y, Mori M. RGS16 is a marker for prognosis in colorectal cancer. Ann Surg Oncol 2009; 16:3507-14. [PMID: 19760045 DOI: 10.1245/s10434-009-0690-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2008] [Revised: 07/02/2009] [Accepted: 07/03/2009] [Indexed: 01/15/2023]
Abstract
BACKGROUND The RGS family, comprising 22 homologues of proteins, plays a role in cellular proliferation, differentiation, membrane trafficking, and embryonic development through the involvement of the mitogen-activated protein kinase signaling pathway. METHODS In order to demonstrate the importance of RGS16 expression for the prediction of prognosis of colorectal cancer (CRC), we analyzed RGS16 gene expression in 22 human gastrointestinal cell lines and 124 paired cases of CRC and noncancerous regions. RESULTS RGS16 was expressed in 17 human gastrointestinal cancer cell lines examined in this study. RGS16 expression was higher in colorectal cancer tissue than in corresponding normal tissue (P < 0.001) in messenger RNA (mRNA) and protein levels. Patients in the RGS16 high-expression group showed a poorer overall survival rate than those in the low-expression group (P < 0.001), indicating that high RGS16 expression was an independent prognostic factor. CONCLUSION The present study suggests that RGS16 is useful as a predictive marker for patient prognosis of CRC.
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Affiliation(s)
- Norikatsu Miyoshi
- Department of Gastroenterological Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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23
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Hurst JH, Hooks SB. Regulator of G-protein signaling (RGS) proteins in cancer biology. Biochem Pharmacol 2009; 78:1289-97. [PMID: 19559677 DOI: 10.1016/j.bcp.2009.06.028] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 06/16/2009] [Accepted: 06/18/2009] [Indexed: 01/09/2023]
Abstract
The regulator of G-protein signaling (RGS) family is a diverse group of multifunctional proteins that regulate cellular signaling events downstream of G-protein coupled receptors (GPCRs). In recent years, GPCRs have been linked to the initiation and progression of multiple cancers; thus, regulators of GPCR signaling are also likely to be important to the pathophysiology of cancer. This review highlights recent studies detailing changes in RGS transcript expression during oncogenesis, single nucleotide polymorphisms in RGS proteins linked to lung and bladder cancers, and specific roles for RGS proteins in multiple cancer types.
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Affiliation(s)
- Jillian H Hurst
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA 30602, USA
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24
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Liang G, Bansal G, Xie Z, Druey KM. RGS16 inhibits breast cancer cell growth by mitigating phosphatidylinositol 3-kinase signaling. J Biol Chem 2009; 284:21719-27. [PMID: 19509421 DOI: 10.1074/jbc.m109.028407] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aberrant activity of the phosphatidylinositol 3-kinase (PI3K) pathway supports growth of many tumors including those of breast, lung, and prostate. Resistance of breast cancer cells to targeted chemotherapies including tyrosine kinase inhibitors (TKI) has been linked to persistent PI3K activity, which may in part be due to increased membrane expression of epidermal growth factor (EGF) receptors (HER2 and HER3). Recently we found that proteins of the RGS (regulator of G protein signaling) family suppress PI3K activity downstream of the receptor by sequestering its p85alpha subunit from signaling complexes. Because a substantial percentage of breast tumors have RGS16 mutations and reduced RGS16 protein expression, we investigated the link between regulation of PI3K activity by RGS16 and breast cancer cell growth. RGS16 overexpression in MCF7 breast cancer cells inhibited EGF-induced proliferation and Akt phosphorylation, whereas shRNA-mediated extinction of RGS16 augmented cell growth and resistance to TKI treatment. Exposure to TKI also reduced RGS16 expression in MCF7 and BT474 cell lines. RGS16 bound the amino-terminal SH2 and inter-SH2 domains of p85alpha and inhibited its interaction with the EGF receptor-associated adapter protein Gab1. These results suggest that the loss of RGS16 in some breast tumors enhances PI3K signaling elicited by growth factors and thereby promotes proliferation and TKI evasion downstream of HER activation.
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Affiliation(s)
- Genqing Liang
- Molecular Signal Transduction Section, Laboratory of Allergic Diseases, NIAID, National Institutes of Health, Bethesda, Maryland 20892, USA
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