1
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Co-ordinated control of the Aurora B abscission checkpoint by PKCε complex assembly, midbody recruitment and retention. Biochem J 2021; 478:2247-2263. [PMID: 34143863 PMCID: PMC8238520 DOI: 10.1042/bcj20210283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 11/17/2022]
Abstract
A requirement for PKCε in exiting from the Aurora B dependent abscission checkpoint is associated with events at the midbody, however, the recruitment, retention and action of PKCε in this compartment are poorly understood. Here, the prerequisite for 14-3-3 complex assembly in this pathway is directly linked to the phosphorylation of Aurora B S227 at the midbody. However, while essential for PKCε control of Aurora B, 14-3-3 association is shown to be unnecessary for the activity-dependent enrichment of PKCε at the midbody. This localisation is demonstrated to be an autonomous property of the inactive PKCε D532N mutant, consistent with activity-dependent dissociation. The C1A and C1B domains are necessary for this localisation, while the C2 domain and inter-C1 domain (IC1D) are necessary for retention at the midbody. Furthermore, it is shown that while the IC1D mutant retains 14-3-3 complex proficiency, it does not support Aurora B phosphorylation, nor rescues division failure observed with knockdown of endogenous PKCε. It is concluded that the concerted action of multiple independent events facilitates PKCε phosphorylation of Aurora B at the midbody to control exit from the abscission checkpoint.
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2
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Karamitrousis EI, Balgkouranidou I, Xenidis N, Amarantidis K, Biziota E, Koukaki T, Trypsianis G, Karayiannakis A, Bolanaki H, Kolios G, Lianidou E, Kakolyris S. Prognostic Role of RASSF1A, SOX17 and Wif-1 Promoter Methylation Status in Cell-Free DNA of Advanced Gastric Cancer Patients. Technol Cancer Res Treat 2021; 20:1533033820973279. [PMID: 33928818 PMCID: PMC8113658 DOI: 10.1177/1533033820973279] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Epigenetic modification of several genes is a key component in the development of gastric cancer. The methylation status of RASSF1A, SOX17 and Wif-1 genes was evaluated in the cell free circulating DNA of 70 patients with advanced gastric cancer, using methylation-specific PCR. Patients with higher cell-free DNA concentration seem to have lower PFS, than patients with lower cell-free DNA concentration (p = 0.001). RASSF1A was the tumor suppressor gene, most frequently methylated in metastatic gastric cancer patients, followed by SOX17 and Wif-1 (74.3%, 60.0% and 47.1%, respectively). Patients having the SOX17 promoter methylated, had lower progression free survival and overall survival, than unmethylated ones (p < 0.001). Patients having the Wif-1 promoter methylated, had lower progression free survival and overall survival, than unmethylated ones (p = 0.001). Patients having the RASSF1A promoter methylated, had lower progression free survival and overall survival, than unmethylated ones (p = 0.004). Promoter methylation of the examined genes was significantly associated with a decrease in progression free survival and overall survival, comparing to that of patients without methylation. Simultaneous methylation of the above genes was associated with even worse progression free survival and overall survival. The methylation of RASSF1A, SOX-17 and Wif-1 and genes, is a frequent epigenetic event in patients with advanced gastric cancer.
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Affiliation(s)
| | - Ioanna Balgkouranidou
- Department of Oncology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Nikolaos Xenidis
- Department of Oncology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Kyriakos Amarantidis
- Department of Oncology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Eirini Biziota
- Department of Oncology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Triantafyllia Koukaki
- Department of Oncology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Grigorios Trypsianis
- Department of Medical Statistics, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Anastasios Karayiannakis
- Second Department of Surgery, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Helen Bolanaki
- Second Department of Surgery, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - George Kolios
- Laboratory of Pharmacology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Evi Lianidou
- Department of Chemistry, Analysis of Circulating Tumor Cells, Lab of Analytical Chemistry, University of Athens, Athens, Greece
| | - Stylianos Kakolyris
- Department of Oncology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
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3
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Karamitrousis E, Balgkouranidou I, Xenidis N, Amarantidis K, Biziota E, Koukaki T, Trypsianis G, Karayiannakis A, Bolanaki H, Chatzaki E, Kolios G, Lianidou E, Lambropoulou M, Kakolyris S. Association between SOX17, Wif-1 and RASSF1A promoter methylation status and response to chemotherapy in patients with metastatic gastric cancer. ACTA ACUST UNITED AC 2020; 59:e73-e75. [DOI: 10.1515/cclm-2020-0662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 08/17/2020] [Indexed: 01/09/2023]
Affiliation(s)
- Evangelos Karamitrousis
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Ioanna Balgkouranidou
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Nikolaos Xenidis
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Kyriakos Amarantidis
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Eirini Biziota
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Triantafyllia Koukaki
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Gregorios Trypsianis
- Department of Medical Statistics, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Anastasios Karayiannakis
- Second Department of Surgery, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Heleni Bolanaki
- Second Department of Surgery, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Ekaterini Chatzaki
- Laboratory of Pharmacology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Georgios Kolios
- Laboratory of Pharmacology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Evi Lianidou
- Analysis of Circulating Tumor Cells, Laboratory of Analytical Chemistry , Department of Chemistry, University of Athens , Athens , Greece
| | - Maria Lambropoulou
- Laboratory of Histology-Embryology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
| | - Stylianos Kakolyris
- Department of Oncology, Medical School, Democritus University of Thrace , Alexandroupolis , Greece
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4
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Tricistronic expression of MOAP-1, Bax and RASSF1A in cancer cells enhances chemo-sensitization that requires BH3L domain of MOAP-1. J Cancer Res Clin Oncol 2020; 146:1751-1764. [DOI: 10.1007/s00432-020-03231-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 04/21/2020] [Indexed: 01/15/2023]
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5
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García-Gutiérrez L, McKenna S, Kolch W, Matallanas D. RASSF1A Tumour Suppressor: Target the Network for Effective Cancer Therapy. Cancers (Basel) 2020; 12:cancers12010229. [PMID: 31963420 PMCID: PMC7017281 DOI: 10.3390/cancers12010229] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/12/2020] [Accepted: 01/14/2020] [Indexed: 02/06/2023] Open
Abstract
The RASSF1A tumour suppressor is a scaffold protein that is involved in cell signalling. Increasing evidence shows that this protein sits at the crossroad of a complex signalling network, which includes key regulators of cellular homeostasis, such as Ras, MST2/Hippo, p53, and death receptor pathways. The loss of expression of RASSF1A is one of the most common events in solid tumours and is usually caused by gene silencing through DNA methylation. Thus, re-expression of RASSF1A or therapeutic targeting of effector modules of its complex signalling network, is a promising avenue for treating several tumour types. Here, we review the main modules of the RASSF1A signalling network and the evidence for the effects of network deregulation in different cancer types. In particular, we summarise the epigenetic mechanism that mediates RASSF1A promoter methylation and the Hippo and RAF1 signalling modules. Finally, we discuss different strategies that are described for re-establishing RASSF1A function and how a multitargeting pathway approach selecting druggable nodes in this network could lead to new cancer treatments.
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Affiliation(s)
- Lucía García-Gutiérrez
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland; (L.G.-G.); (S.M.); (W.K.)
| | - Stephanie McKenna
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland; (L.G.-G.); (S.M.); (W.K.)
| | - Walter Kolch
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland; (L.G.-G.); (S.M.); (W.K.)
- School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
- Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - David Matallanas
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland; (L.G.-G.); (S.M.); (W.K.)
- School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
- Correspondence:
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6
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Dubois F, Bergot E, Zalcman G, Levallet G. RASSF1A, puppeteer of cellular homeostasis, fights tumorigenesis, and metastasis-an updated review. Cell Death Dis 2019; 10:928. [PMID: 31804463 PMCID: PMC6895193 DOI: 10.1038/s41419-019-2169-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/19/2019] [Accepted: 11/20/2019] [Indexed: 12/27/2022]
Abstract
The Ras association domain family protein1 isoform A (RASSF1A) is a well-known tumor-suppressor protein frequently inactivated in various human cancers. Consistent with its function as a molecular scaffold protein, referred to in many studies, RASSF1A prevents initiation of tumorigenesis, growth, and dissemination through different biological functions, including cell cycle arrest, migration/metastasis inhibition, microtubular stabilization, and apoptosis promotion. As a regulator of key cancer pathways, namely Ras/Rho GTPases and Hippo signaling without ignoring strong interaction with microtubules, RASSF1A is indeed one of the guardians of cell homeostasis. To date, as we approach the two decade anniversary of RASSF1A's discovery, this review will summarize our current knowledge on the RASSF1A key interactions as a tumor suppressor and discuss their impact on cell fate during carcinogenesis. This could facilitate a deeper understanding of tumor development and provide us with new strategies in cancer treatment by targeting the RASSF1A pathway.
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Affiliation(s)
- Fatéméh Dubois
- Normandie University, UNICAEN, CEA, CNRS, ISTCT/CERVOxy group, GIP CYCERON, Caen, France
- Department of Pathology, CHU de Caen, Caen, France
| | - Emmanuel Bergot
- Normandie University, UNICAEN, CEA, CNRS, ISTCT/CERVOxy group, GIP CYCERON, Caen, France
- Department of Pulmonology & Thoracic Oncology, CHU de Caen, Caen, France
| | - Gérard Zalcman
- U830 INSERM "Genetics and biology of cancers, A.R.T group", Curie Institute, Paris, France
- Department of Thoracic Oncology & CIC1425, Hôpital Bichat-Claude Bernard, Assistance Publique Hôpitaux de Paris, Université Paris-Diderot, Paris, France
| | - Guénaëlle Levallet
- Normandie University, UNICAEN, CEA, CNRS, ISTCT/CERVOxy group, GIP CYCERON, Caen, France.
- Department of Pathology, CHU de Caen, Caen, France.
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7
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RACK1/TRAF2 regulation of modulator of apoptosis-1 (MOAP-1). BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:684-694. [DOI: 10.1016/j.bbamcr.2018.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 02/14/2018] [Accepted: 02/18/2018] [Indexed: 01/23/2023]
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8
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Iwasa H, Hossain S, Hata Y. Tumor suppressor C-RASSF proteins. Cell Mol Life Sci 2018; 75:1773-1787. [PMID: 29353317 PMCID: PMC11105443 DOI: 10.1007/s00018-018-2756-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 01/05/2018] [Accepted: 01/17/2018] [Indexed: 12/13/2022]
Abstract
Human genome has ten genes that are collectedly called Ras association domain family (RASSF). RASSF is composed of two subclasses, C-RASSF and N-RASSF. Both N-RASSF and C-RASSF encode Ras association domain-containing proteins and are frequently suppressed by DNA hypermethylation in human cancers. However, C-RASSF and N-RASSF are quite different. Six C-RASSF proteins (RASSF1-6) are characterized by a C-terminal coiled-coil motif named Salvador/RASSF/Hippo domain, while four N-RASSF proteins (RASSF7-10) lack it. C-RASSF proteins interact with mammalian Ste20-like kinases-the core kinases of the tumor suppressor Hippo pathway-and cross-talk with this pathway. Some of them share the same interacting molecules such as MDM2 and exert the tumor suppressor role in similar manners. Nevertheless, each C-RASSF protein has distinct characters. In this review, we summarize our current knowledge of how C-RASSF proteins play tumor suppressor roles and discuss the similarities and differences among C-RASSF proteins.
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Affiliation(s)
- Hiroaki Iwasa
- Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| | - Shakhawoat Hossain
- Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
- Department of Biochemistry and Molecular Biology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Yutaka Hata
- Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, 113-8519, Japan.
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9
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Pang SW, Lahiri C, Poh CL, Tan KO. PNMA family: Protein interaction network and cell signalling pathways implicated in cancer and apoptosis. Cell Signal 2018; 45:54-62. [PMID: 29378289 DOI: 10.1016/j.cellsig.2018.01.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/23/2018] [Accepted: 01/23/2018] [Indexed: 12/22/2022]
Abstract
Paraneoplastic Ma Family (PNMA) comprises a growing number of family members which share relatively conserved protein sequences encoded by the human genome and is localized to several human chromosomes, including the X-chromosome. Based on sequence analysis, PNMA family members share sequence homology to the Gag protein of LTR retrotransposon, and several family members with aberrant protein expressions have been reported to be closely associated with the human Paraneoplastic Disorder (PND). In addition, gene mutations of specific members of PNMA family are known to be associated with human mental retardation or 3-M syndrome consisting of restrictive post-natal growth or dwarfism, and development of skeletal abnormalities. Other than sequence homology, the physiological function of many members in this family remains unclear. However, several members of this family have been characterized, including cell signalling events mediated by these proteins that are associated with apoptosis, and cancer in different cell types. Furthermore, while certain PNMA family members show restricted gene expression in the human brain and testis, other PNMA family members exhibit broader gene expression or preferential and selective protein interaction profiles, suggesting functional divergence within the family. Functional analysis of some members of this family have identified protein domains that are required for subcellular localization, protein-protein interactions, and cell signalling events which are the focus of this review paper.
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Affiliation(s)
- Siew Wai Pang
- Department of Biological Sciences, Sunway University, Bandar Sunway, 47500, Selangor Darul Ehsan, Malaysia
| | - Chandrajit Lahiri
- Department of Biological Sciences, Sunway University, Bandar Sunway, 47500, Selangor Darul Ehsan, Malaysia
| | - Chit Laa Poh
- Research Centre for Biomedical Sciences, Sunway University, Bandar Sunway, 47500, Selangor Darul Ehsan, Malaysia
| | - Kuan Onn Tan
- Department of Biological Sciences, Sunway University, Bandar Sunway, 47500, Selangor Darul Ehsan, Malaysia.
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10
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Jezkova E, Zubor P, Kajo K, Grendar M, Dokus K, Adamkov M, Lasabova Z, Plank L, Danko J. Impact of RASSF1A gene methylation on the metastatic axillary nodal status in breast cancer patients. Oncol Lett 2017; 14:758-766. [PMID: 28693231 PMCID: PMC5494671 DOI: 10.3892/ol.2017.6204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 01/31/2017] [Indexed: 12/13/2022] Open
Abstract
Hypermethylation of CpG islands is a hallmark of cancer and occurs at an early stage in breast tumorigenesis. To gain insight into the epigenetic switches that may promote and/or contribute to the initial neoplastic events during breast carcinogenesis, the present study focused on the DNA methylation profile of invasive breast carcinoma. The aim of the study was to evaluate the prognostic significance of Ras association domain family 1 isoform A (RASSF1A) promoter methylation status in operable breast cancer, and to analyze the utility of this biomarker regarding its association with metastatic and nonmetastatic axillary nodal status. For this purpose, formalin-fixed, paraffin-embedded tissue specimens from 116 breast cancer patients with known axillary nodal status were subjected to assessment of RASSF1A promoter methylation status by methylation-specific polymerase chain reaction (MSP) and methylation-sensitive high-resolution melting assay, and the results were subsequently validated by bisulfite sequencing. A multinomial logistic regression model was used to model the dependence of distinct levels of methylation status of the RASSF1A promoter on the nodal status. Promoter region CpG hypermethylation was identified by MSP in 97 (83.6%) of 116 primary breast tumors, while hypermethylation of RASSF1A was confirmed by MS-HRM in 107 (92.2%) of 116 cases of breast cancer. Based on the results of the multinomial logistic regression model, there was no significant difference between the frequency of RASSF1A promoter methylation and axillary lymph node status of patients in general. However, upon adjustment of pN stage, an association was identified between pN0 lymph node-negative status (without axillary metastases) and percentage of RASSF1A methylation in two groups of heterogeneous methylated alleles with ≤50% methylated (P<0.05) and >50% methylated alleles (P<0.0001). If a patients' nodal status changes from pN- to pN+ then the risk of having >50% methylated alleles increases by 7%. The present study revealed a specific phenomenon, suggesting that the presence of heterogeneous methylated alleles in the RASSF1A gene is significantly associated with lymph node-negative status in breast cancer patients. Furthermore, greater significance with negative axillary nodal status was observed with a higher level of heterogeneous methylated alleles in the RASSF1A gene.
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Affiliation(s)
- Eva Jezkova
- Department of Oncology, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia.,Department of Histology and Embryology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Pavol Zubor
- Department of Oncology, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia.,Department of Obstetrics and Gynaecology, Jessenius Faculty of Medicine, Martin University Hospital, 036 01 Martin, Slovakia
| | - Karol Kajo
- St. Elizabeth Cancer Institute Hospital, 812 50 Bratislava, Slovakia
| | - Marian Grendar
- Bioinformatic Unit, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Karol Dokus
- Department of Obstetrics and Gynaecology, Jessenius Faculty of Medicine, Martin University Hospital, 036 01 Martin, Slovakia
| | - Marian Adamkov
- Department of Histology and Embryology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Zora Lasabova
- Department of Oncology, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Lukas Plank
- Department of Pathological Anatomy, Jessenius Faculty of Medicine, Martin University Hospital, 036 01 Martin, Slovakia
| | - Jan Danko
- Department of Obstetrics and Gynaecology, Jessenius Faculty of Medicine, Martin University Hospital, 036 01 Martin, Slovakia
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Matthaios D, Balgkouranidou I, Karayiannakis A, Bolanaki H, Xenidis N, Amarantidis K, Chelis L, Romanidis K, Chatzaki A, Lianidou E, Trypsianis G, Kakolyris S. Methylation status of the APC and RASSF1A promoter in cell-free circulating DNA and its prognostic role in patients with colorectal cancer. Oncol Lett 2016; 12:748-756. [PMID: 27347211 DOI: 10.3892/ol.2016.4649] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 04/29/2016] [Indexed: 01/26/2023] Open
Abstract
DNA methylation is the most frequent epigenetic alteration. Using methylation-specific polymerase chain reaction (MSP), the methylation status of the adenomatous polyposis coli (APC) and Ras association domain family 1 isoform A (RASSF1A) genes was examined in cell-free circulating DNA from 155 plasma samples obtained from patients with early and advanced colorectal cancer (CRC). APC and RASSF1A hypermethylation was frequently observed in both early and advanced disease, and was significantly associated with a poorer disease outcome. The methylation status of the APC and RASSF1A promoters was investigated in cell-free DNA of patients with CRC. Using MSP, the promoter methylation status of APC and RASSF1A was examined in 155 blood samples obtained from patients with CRC, 88 of whom had operable CRC (oCRC) and 67 had metastatic CRC (mCRC). The frequency of APC methylation in patients with oCRC was 33%. Methylated APC promoter was significantly associated with older age (P=0.012), higher stage (P=0.014) and methylated RASSF1A status (P=0.050). The frequency of APC methylation in patients with mCRC was 53.7%. In these patients, APC methylation was significantly associated with methylated RASSF1A status (P=0.016). The frequency of RASSF1A methylation in patients with oCRC was 25%. Methylated RASSF1A in oCRC was significantly associated with higher stage (P=0.021). The frequency of RASSF1A methylation in mCRC was 44.8%. Methylated RASSF1A in mCRC was associated with moderate differentiation (P=0.012), high levels of carcinoembryonic antigen (P=0.023) and methylated APC status (P=0.016). Patients with an unmethylated APC gene had better survival in both early (81±5 vs. 27±4 months, P<0.001) and advanced disease (37±7 vs. 15±3 months, P<0.001), compared with patients with methylated APC. Patients with an unmethylated RASSF1A gene had better survival in both early (71±6 vs. 46±8 months, P<0.001) and advanced disease (28±4 vs. 16±3 months, P<0.001) than patients with methylated RASSF1A. The observed significant correlations between APC and RASSF1A promoter methylation status and survival may be indicative of a prognostic role for these genes in CRC, which requires additional testing in larger studies.
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Affiliation(s)
- Dimitrios Matthaios
- Department of Medical Oncology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Ioanna Balgkouranidou
- Department of Medical Oncology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Anastasios Karayiannakis
- Second Department of Surgery, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Helen Bolanaki
- Second Department of Surgery, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Nikolaos Xenidis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Kyriakos Amarantidis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Leonidas Chelis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Konstantinos Romanidis
- Second Department of Surgery, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Aikaterini Chatzaki
- Laboratory of Pharmacology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Evi Lianidou
- Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Athens 15771, Greece
| | - Grigorios Trypsianis
- Laboratory of Statistics, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
| | - Stylianos Kakolyris
- Department of Medical Oncology, Medical School, Democritus University of Thrace, University General Hospital of Alexandroupolis, Alexandroupolis 68100, Greece
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12
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Balgkouranidou I, Matthaios D, Karayiannakis A, Bolanaki H, Michailidis P, Xenidis N, Amarantidis K, Chelis L, Trypsianis G, Chatzaki E, Lianidou ES, Kakolyris S. Prognostic role of APC and RASSF1A promoter methylation status in cell free circulating DNA of operable gastric cancer patients. Mutat Res 2015; 778:46-51. [PMID: 26073472 DOI: 10.1016/j.mrfmmm.2015.05.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 04/18/2015] [Accepted: 05/09/2015] [Indexed: 12/12/2022]
Abstract
Gastric carcinogenesis is a multistep process including not only genetic mutations but also epigenetic alterations. The best known and more frequent epigenetic alteration is DNA methylation affecting tumor suppressor genes that may be involved in various carcinogenetic pathways. The aim of the present study was to investigate the methylation status of APC promoter 1A and RASSF1A promoter in cell free DNA of operable gastric cancer patients. Using methylation specific PCR, we examined the methylation status of APC promoter 1A and RASSF1A promoter in 73 blood samples obtained from patients with gastric cancer. APC and RASSF1A promoters were found to be methylated in 61 (83.6%) and 50 (68.5%) of the 73 gastric cancer samples examined, but in none of the healthy control samples (p < 0.001). A significant association between methylated RASSF1A promoter status and lymph node positivity was observed (p = 0.005). Additionally, a significant correlation between a methylated APC promoter and elevated CEA (p = 0.033) as well as CA-19.9 (p = 0.032) levels, was noticed. The Kaplan-Meier estimates of survival, significantly favored patients with a non-methylated APC promoter status (p = 0.008). No other significant correlations between APC and RASSF1A methylation status and different tumor variables examined was observed. Serum RASSF1A and APC promoter hypermethylation is a frequent epigenetic event in patients with early operable gastric cancer. The observed correlations between APC promoter methylation status and survival as well as between a hypermethylated RASSF1A promoter and nodal positivity may be indicative of a prognostic role for those genes in early operable gastric cancer. Additional studies, in a larger cohort of patients are required to further explore whether these findings could serve as potential molecular biomarkers of survival and/or response to specific treatments.
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Affiliation(s)
- I Balgkouranidou
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece.
| | - D Matthaios
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece
| | - A Karayiannakis
- Second Department of Surgery, Medical School, Democritus University of Thrace, Greece
| | - H Bolanaki
- Second Department of Surgery, Medical School, Democritus University of Thrace, Greece
| | - P Michailidis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece
| | - N Xenidis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece
| | - K Amarantidis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece
| | - L Chelis
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece
| | - G Trypsianis
- Laboratory of Statistics, Medical School, Democritus University of Thrace, Greece
| | - E Chatzaki
- Department of Pharmacology, Medical School, Democritus University of Thrace, Greece
| | - E S Lianidou
- Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Greece
| | - S Kakolyris
- Department of Medical Oncology, Medical School, Democritus University of Thrace, Greece
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13
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Gordon M, Baksh S. RASSF1A: Not a prototypical Ras effector. Small GTPases 2014; 2:148-157. [PMID: 21776416 DOI: 10.4161/sgtp.2.3.16286] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 04/28/2011] [Accepted: 05/02/2011] [Indexed: 01/25/2023] Open
Abstract
The Ras association domain family (RASSF) of genes are commonly silenced by promoter specific methylation in human cancers. After the cloning of the first two family members in early 2000 (RASSF1 and RASSF5), eight other related genes have been identified (RASSF2, 3, 4 and 6-10). The unifying motif amongst all RASSF family members is the presence of the Ras association (RA) domain that could potentially associate with the Ras family of GTPases. Detailed analyses have determined that RASSF family members are tumor suppressor proteins, activators of cell death, cell cycle modulators, microtubule stabilizers and possibly inflammatory mediators linked to NFκB. As such, exploring the biological function of this gene family is needed and if indeed RASSF proteins could be the missing link between Ras signaling and apoptosis. Several RASSF family members have been demonstrated to associate with Ras. However, there is still controversy regarding the ability of RASSF1A to utilize Ras to promote cell death and of the importance of the RASSF1A RA domain. The focus of this review is to highlight the importance of Ras binding to the RASSF family of proteins and discuss what we currently know about the biology of RASSF1A.
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Affiliation(s)
- Marilyn Gordon
- Department of Pediatrics; Faculty of Medicine and Dentistry; University of Alberta; Edmonton, AB Canada
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14
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Volodko N, Gordon M, Salla M, Ghazaleh HA, Baksh S. RASSF tumor suppressor gene family: Biological functions and regulation. FEBS Lett 2014; 588:2671-84. [DOI: 10.1016/j.febslet.2014.02.041] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 02/25/2014] [Accepted: 02/25/2014] [Indexed: 01/22/2023]
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15
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Modulator of Apoptosis 1: A Highly Regulated RASSF1A-Interacting BH3-Like Protein. Mol Biol Int 2012; 2012:536802. [PMID: 22745908 PMCID: PMC3382356 DOI: 10.1155/2012/536802] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 03/29/2012] [Accepted: 04/03/2012] [Indexed: 01/03/2023] Open
Abstract
Modulator of apoptosis 1 (MOAP-1) is a BH3-like protein that plays key roles in both the intrinsic and extrinsic modes of cell death or apoptosis. MOAP-1 is part of the Ras association domain family 1A (RASSF1A)/MOAP-1 pro-apoptotic extrinsic signaling pathway that regulates apoptosis by utilizing death receptors such as tumor necrosis factor α (TNFα) or TNF-related apoptosis-inducing ligand (TRAIL) to inhibit abnormal growth. RASSF1A is a bona fide tumor suppressor gene that is epigenetically silenced by promoter-specific methylation in numerous human cancers. MOAP-1 is a downstream effector of RASSF1A that promotes Bax activation and cell death and is highly regulated during apoptosis. We speculate that MOAP-1 and RASSF1A are important elements of an “apoptotic checkpoint” that directly influences the outcome of cell death. The failure to regulate this pro-apoptotic pathway may result in the appearance of cancer and possibly other disorders. Although loss of RASSF1A expression is frequently observed in human cancers, it is currently unknown if MOAP-1 expression may also be affected during carcinogenesis to result in uncontrolled malignant growth. In this article, we will summarize what is known about the biological role(s) of MOAP-1 and how it functions as a downstream effector to RASSF1A.
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16
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Gordon M, El-Kalla M, Baksh S. RASSF1 Polymorphisms in Cancer. Mol Biol Int 2012; 2012:365213. [PMID: 22701175 PMCID: PMC3371342 DOI: 10.1155/2012/365213] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 03/01/2012] [Indexed: 12/29/2022] Open
Abstract
Ras association domain family 1A (RASSF1A) is one of the most epigenetically silenced elements in human cancers. Localized on chromosome 3, it has been demonstrated to be a bone fide tumor suppressor influencing cell cycle events, microtubule stability, apoptosis, and autophagy. Although it is epigenetically silenced by promoter-specific methylation in cancers, several somatic nucleotide changes (polymorphisms) have been identified in RASSF1A in tissues from cancer patients. We speculate that both nucleotide changes and epigenetic silencing result in loss of the RASSF1A tumor suppressor function and the appearance of enhanced growth. This paper will summarize what is known about the origin of these polymorphisms and how they have helped us understand the biological role of RASSF1A.
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Affiliation(s)
- Marilyn Gordon
- Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, 3-055 Katz Group Centre for Pharmacy and Health Research, 113 Street 87 Avenue, Edmonton, AB, Canada T6G 2E1
- Women and Children's Health Research Institute, University of Alberta, 4-081 Edmonton Clinic Health Academy, 11405-87 Avenue, Edmonton, AB, Canada T6G 1C9
| | - Mohamed El-Kalla
- Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, 3-055 Katz Group Centre for Pharmacy and Health Research, 113 Street 87 Avenue, Edmonton, AB, Canada T6G 2E1
- Women and Children's Health Research Institute, University of Alberta, 4-081 Edmonton Clinic Health Academy, 11405-87 Avenue, Edmonton, AB, Canada T6G 1C9
| | - Shairaz Baksh
- Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, 3-055 Katz Group Centre for Pharmacy and Health Research, 113 Street 87 Avenue, Edmonton, AB, Canada T6G 2E1
- Women and Children's Health Research Institute, University of Alberta, 4-081 Edmonton Clinic Health Academy, 11405-87 Avenue, Edmonton, AB, Canada T6G 1C9
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17
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Combined RASSF1A and RASSF2A Promoter Methylation Analysis as Diagnostic Biomarker for Bladder Cancer. Mol Biol Int 2012; 2012:701814. [PMID: 22530128 PMCID: PMC3316979 DOI: 10.1155/2012/701814] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 12/29/2011] [Indexed: 11/25/2022] Open
Abstract
Promoter hypermethylation, a widely studied epigenetic event known to influence gene expression levels, has been proposed as a potential biomarker in multiple types of cancer. Clinical diagnostic biomarkers are needed for reliable prediction of bladder cancer recurrence. In this paper, DNA promoter methylation of five C-terminal Ras-association family members (RASSF1A, RASSF2A, RASSF4, RASSF5, and RASSF6) was studied in 64 formalin-fixed paraffin-embedded (FFPE) bladder cancer and normal adjacent tissues using methylation-specific high-resolution melting (MS-HRM) analysis. Results showed that 73% (30/41) of transitional cell carcinoma, 100% (3/3) of squamous cell carcinoma, and 100% (4/4) of small cell carcinoma demonstrated promoter methylation of the RASSF1A or RASSF2A gene, but only 6% (1/16) of normal tissues had promoter methylation of RASSF genes. Testing positive for hypermethylation of RASSF1A or RASSF2A promoter provided 77% sensitivity and 94% specificity for identification of cancer tissues with an area under the curve of 0.854, suggesting that promoter methylation analysis of RASSF1A and RASSF2A genes has potential for use as a recurrence biomarker for bladder cancer patients.
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18
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Amin KS, Banerjee PP. The cellular functions of RASSF1A and its inactivation in prostate cancer. J Carcinog 2012; 11:3. [PMID: 22438769 PMCID: PMC3307426 DOI: 10.4103/1477-3163.93000] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 11/11/2011] [Indexed: 12/18/2022] Open
Abstract
Epigenetic events significantly impact the transcriptome of cells and often contribute to the onset and progression of human cancers. RASSF1A (Ras-association domain family 1 isoform A), a well-known tumor suppressor gene, is frequently silenced by epigenetic mechanisms such as promoter hypermethylation in a wide range of cancers. In the past decade a vast body of literature has emerged describing the silencing of RASSF1A expression in various cancers and demonstrating its ability to reverse the cancerous phenotype when re-expressed in cancer cells. However, the mechanisms by which RASSF1A exerts its tumor suppressive properties have not been entirely defined. RASSF1A appears to mediate three important cellular processes: microtubule stability, cell cycle progression, and the induction of apoptosis through specific molecular interactions with key factors involved in these processes. Loss of function of RASSF1A leads to accelerated cell cycle progression and resistance to apoptotic signals, resulting in increased cell proliferation. In this review, we attempt to summarize the current understanding of the biological functions of RASSF1A and provide insight that the development of targeted drugs to restore RASSF1A function holds promise for the treatment of prostate cancer.
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Affiliation(s)
- Karishma S Amin
- Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington DC, USA
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19
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Targeted polyubiquitylation of RASSF1C by the Mule and SCFβ-TrCP ligases in response to DNA damage. Biochem J 2012; 441:227-36. [PMID: 21910689 DOI: 10.1042/bj20111500] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
RASSF1A [Ras association (RalGDS/AF-6) domain family member 1A] and RASSF1C are two ubiquitously expressed isoforms of the RASSF1 gene. The promoter of RASSF1A is frequently hypermethylated, resulting in inactivation in various human cancers. RASSF1A is implicated in the regulation of apoptosis, microtubule stability and cell cycle arrest. However, little is known about the regulation and function of RASSF1C. In the present study we show that exogenously expressed RASSF1C is a very unstable protein that is highly polyubiquitylated and degraded via the proteasome. Furthermore, RASSF1C degradation is enhanced when cells are exposed to stress signals, such as UV irradiation. Mule, a HECT (homologous with E6-associated protein C-terminus) family E3 ligase, but not SCFβ-TrCP [where SCF is Skp1 (S-phase kinase-associated protein 1)/cullin/F-box and β-TrCP is β-bransducin repeat-containing protein] or CUL4 (cullin 4)-DDB1 (damage-specific DNA-binding protein 1), is the E3 ligase for RASSF1C under normal conditions, whereas both Mule and SCFβ-TrCP target RASSF1C degradation in response to UV irradiation. GSK3 (glycogen synthase kinase 3) phosphorylates RASSF1C to promote RASSF1C degradation subsequently, which is negatively regulated by the PI3K (phosphoinositide 3-kinase)/Akt pathway. Thus the present study reveals a novel regulation of RASSF1C and the potentially important role of RASSF1C in DNA damage responses.
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20
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Gardino AK, Yaffe MB. 14-3-3 proteins as signaling integration points for cell cycle control and apoptosis. Semin Cell Dev Biol 2011; 22:688-95. [PMID: 21945648 DOI: 10.1016/j.semcdb.2011.09.008] [Citation(s) in RCA: 206] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 09/09/2011] [Indexed: 12/11/2022]
Abstract
14-3-3 proteins play critical roles in the regulation of cell fate through phospho-dependent binding to a large number of intracellular proteins that are targeted by various classes of protein kinases. 14-3-3 proteins play particularly important roles in coordinating progression of cells through the cell cycle, regulating their response to DNA damage, and influencing life-death decisions following internal injury or external cytokine-mediated cues. This review focuses on 14-3-3-dependent pathways that control cell cycle arrest and recovery, and the influence of 14-3-3 on the apoptotic machinery at multiple levels of regulation. Recognition of 14-3-3 proteins as signaling integrators that connect protein kinase signaling pathways to resulting cellular phenotypes, and their exquisite control through feedforward and feedback loops, identifies new drug targets for human disease, and highlights the emerging importance of using systems-based approaches to understand signal transduction events at the network biology level.
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Affiliation(s)
- Alexandra K Gardino
- Department of Biology, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute for Technology, Cambridge, MA 02139, USA.
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21
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Levesley J, Lusher ME, Lindsey JC, Clifford SC, Grundy R, Coyle B. RASSF1A and the BH3-only mimetic ABT-737 promote apoptosis in pediatric medulloblastoma cell lines. Neuro Oncol 2011; 13:1265-76. [PMID: 21880625 DOI: 10.1093/neuonc/nor129] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The RASSF1A tumor suppressor is potentially the most important candidate gene identified in medulloblastoma to date, being epigenetically silenced in >79% of primary tumors. However, its functional role has not been previously addressed in this tumor type. Here, we demonstrate that expression of RASSF1A promotes the induction of cell death after activation of both the extrinsic and intrinsic apoptotic pathways in medulloblastoma cells. Treatment of UW228-3 cells stably expressing RASSF1A with an anti-CD95 antibody to induce extrinsic apoptosis and etoposide or cisplatin to activate intrinsic apoptosis augmented tumor cell killing in a caspase-dependent manner. This led to increased activation of the pro-apoptotic BCL-2 family member BAX. On the basis of this knowledge, we demonstrate how the loss of RASSF1A function in medulloblastoma cells might be overcome using the novel BH3-only mimetic ABT-737 in combination with chemotherapeutic agents to target the BCL-2 anti-apoptotic members. We show that ABT-737 increased susceptibility to apoptosis induced by DNA damage regardless of RASSF1A expression status through increased activation of BAX. Our findings identify the RASSF1A tumor suppressor as a promoter of apoptotic signaling pathways. Investigation of its mechanism of action has revealed that these pathways can still be promoted in its absence and how these potentially represent novel therapeutic targets for medulloblastoma.
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Affiliation(s)
- Jane Levesley
- Children's Brain Tumour Research Centre, Queen's Medical Centre, Medical School, Nottingham University, Nottingham NG7 2UH, UK
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22
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El-Kalla M, Onyskiw C, Baksh S. Functional importance of RASSF1A microtubule localization and polymorphisms. Oncogene 2010; 29:5729-40. [PMID: 20697344 DOI: 10.1038/onc.2010.316] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Ras association domain family protein 1A (RASSF1A) is one of the more heavily methylated genes in human cancers. In addition to promoter-specific methylation, RASSF1A polymorphisms have been identified in cancer patients. RASSF1A is a tumor suppressor protein involved in death receptor-dependent apoptosis and it is localized to microtubules. Currently, the biological importance of RASSF1A microtubule localization and the functional consequences of RASSF1A polymorphisms is not understood. In this study, we have investigated both RASSF1A microtubule association and polymorphisms. Loss of RASSF1A microtubule association resulted in the nuclear appearance of RASSF1A and the loss of association with α-, γ- and β-tubulin. Moreover, the loss of microtubule localization of RASSF1A resulted in enhanced tumor-promoting potential, as determined by a xenograft transplantation model in nude mice. It is surprising that, several RASSF1A polymorphisms also lost the ability to associate with α-, γ- and β-tubulin and lost the ability to prevent tumor formation in a xenograft nude mouse model when compared with wild-type RASSF1A. Our results demonstrate a role for RASSF1A microtubule localization in eliciting its tumor suppressor function. In addition, some RASSF1A polymorphisms lack the tumor suppressor function of RASSF1A and, if present in patients, may be tumorigenic.
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Affiliation(s)
- M El-Kalla
- Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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