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Baek JW, Nam AR, Kim K, Kim PH. Dualistic Effects of PRKAR1A as a Potential Anticancer Target in Cancer Cells and Cancer-Derived Stem Cells. Int J Mol Sci 2024; 25:2876. [PMID: 38474121 DOI: 10.3390/ijms25052876] [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: 01/21/2024] [Revised: 02/21/2024] [Accepted: 02/28/2024] [Indexed: 03/14/2024] Open
Abstract
The integration of innovative medical technologies and interdisciplinary collaboration could improve the treatment of cancer, a globally prevalent and often deadly disease. Despite recent advancements, current cancer therapies fail to specifically address recurrence and target cancer stem cells (CSCs), which contribute to relapse. In this study, we utilized three types of cancer cells, from which three types of CSCs were further derived, to conduct a proteomic analysis. Additionally, shared cell surface biomarkers were identified as potential targets for a comprehensive treatment strategy. The selected biomarkers were evaluated through short hairpin RNA treatment, which revealed contrasting functions in cancer cells and CSCs. Knockdown of the identified proteins revealed that they regulate the epithelial-mesenchymal transition (EMT) and stemness via the ERK signaling pathway. Resistance to anticancer agents was consequently reduced, ultimately enhancing the overall anticancer effects of the treatment. Additionally, the significance of these biomarkers in clinical patient outcomes was confirmed using bioinformatics. Our study suggests a novel cancer treatment strategy that addresses the limitations of current anticancer therapies.
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Affiliation(s)
- Joong-Won Baek
- Department of Biomedical Laboratory Science, Konyang University, Daejeon 35365, Republic of Korea
| | - A-Reum Nam
- Department of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
| | - Kyunggon Kim
- Department of Convergence Medicine, Asan Medical Center, Seoul 05505, Republic of Korea
| | - Pyung-Hwan Kim
- Department of Biomedical Laboratory Science, Konyang University, Daejeon 35365, Republic of Korea
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2
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Wu NS, Lin YF, Ma IC, Ko HJ, Hong YR. Many faces and functions of GSKIP: a temporospatial regulation view. Cell Signal 2022; 97:110391. [PMID: 35728705 DOI: 10.1016/j.cellsig.2022.110391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 06/06/2022] [Accepted: 06/16/2022] [Indexed: 11/25/2022]
Abstract
Glycogen synthase kinase 3 (GSK3)-β (GSK3β) interaction protein (GSKIP) is one of the smallest A-kinase anchoring proteins that possesses a binding site for GSK3β. Recently, our group identified the protein kinase A (PKA)-GSKIP-GSK3β-X axis; knowledge of this axis may help us decipher the many roles of GSKIP and perhaps help explain the evolutionary reason behind the interaction between GSK3β and PKA. In this review, we highlight the critical and multifaceted role of GSKIP in facilitating PKA kinase activity and its function as a scaffolding protein in signaling pathways. We also highlight how these pivotal PKA and GSK3 kinases can control context-specific functions and interact with multiple target proteins, such as β-catenin, Drp1, Tau, and other proteins. GSKIP is a key regulator of multiple mechanisms because of not only its location at certain subcellular compartments but also its serial changes during the developmental process. Moreover, the involvement of critical upstream regulatory signaling pathways in GSKIP signaling in various cancers, such as miRNA (microRNA) and lncRNA (long noncoding RNA), may help in the identification of therapeutic targets in the era of precision medicine and personalized therapy. Finally, we emphasize on the model of the early stage of pathogenesis of Alzheimer Disease (AD). Although the model requires validation, it can serve as a basis for diagnostic biomarkers development and drug discovery for early-stage AD.
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Affiliation(s)
- Nian-Siou Wu
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Yi-Fan Lin
- School of Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan.
| | - I Chu Ma
- China Medical University Hospital, Taichung 404, Taiwan.
| | - Huey-Jiun Ko
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Yi-Ren Hong
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan; Graduate Institutes of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan; Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan; Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 807, Taiwan,; Neuroscience Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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3
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Tian W, Liu Y, Cao C, Zeng Y, Pan Y, Liu X, Peng Y, Wu F. Chronic Stress: Impacts on Tumor Microenvironment and Implications for Anti-Cancer Treatments. Front Cell Dev Biol 2021; 9:777018. [PMID: 34869378 PMCID: PMC8640341 DOI: 10.3389/fcell.2021.777018] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/02/2021] [Indexed: 12/12/2022] Open
Abstract
Chronic stress is common among cancer patients due to the psychological, operative, or pharmaceutical stressors at the time of diagnosis or during the treatment of cancers. The continuous activations of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS), as results of chronic stress, have been demonstrated to take part in several cancer-promoting processes, such as tumorigenesis, progression, metastasis, and multi-drug resistance, by altering the tumor microenvironment (TME). Stressed TME is generally characterized by the increased proportion of cancer-promoting cells and cytokines, the reduction and malfunction of immune-supportive cells and cytokines, augmented angiogenesis, enhanced epithelial-mesenchymal transition, and damaged extracellular matrix. For the negative effects that these alterations can cause in terms of the efficacies of anti-cancer treatments and prognosis of patients, supplementary pharmacological or psychotherapeutic strategies targeting HPA, SNS, or psychological stress may be effective in improving the prognosis of cancer patients. Here, we review the characteristics and mechanisms of TME alterations under chronic stress, their influences on anti-cancer therapies, and accessory interventions and therapies for stressed cancer patients.
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Affiliation(s)
- Wentao Tian
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China.,Xiangya School of Medicine, Central South University, Changsha, China
| | - Yi Liu
- Xiangya School of Public Health, Central South University, Changsha, China
| | - Chenghui Cao
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China.,Xiangya School of Medicine, Central South University, Changsha, China
| | - Yue Zeng
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Yue Pan
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Xiaohan Liu
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Yurong Peng
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Fang Wu
- Department of Oncology, The Second Xiangya Hospital, Central South University, Changsha, China.,Hunan Cancer Mega-Data Intelligent Application and Engineering Research Centre, Changsha, China.,Hunan Key Laboratory of Tumor Models and Individualized Medicine, The Second Xiangya Hospital, Central South University, Changsha, China.,Hunan Key Laboratory of Early Diagnosis and Precision Therapy in Lung Cancer, The Second Xiangya Hospital, Central South University, Changsha, China
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4
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Protein Kinase A Catalytic Subunit Is a Molecular Switch that Promotes the Pro-tumoral Function of Macrophages. Cell Rep 2021; 31:107643. [PMID: 32402274 DOI: 10.1016/j.celrep.2020.107643] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 02/07/2020] [Accepted: 04/22/2020] [Indexed: 02/07/2023] Open
Abstract
As current therapies benefit only a minority of cancer patients, additional therapeutic targets are needed. Tumor-associated macrophages (TAMs) have attracted attention for improving therapeutic responses, yet regulatory strategies remain elusive. Here, we show that the protein kinase A catalytic subunit (PKA-C) acts as a molecular switch, inducing a pro-tumoral immunosuppressive macrophage phenotype within tumors. In human and murine breast cancer, overactivated PKA in TAMs creates a detrimental microenvironment for cancer progression by inducing vascular endothelial growth factor A (VEGFA), interleukin-10 (IL-10), and macrophage-derived arginase 1 (ARG1) expression. Macrophages with genetic deletion of PKA-C are prone to be pro-inflammatory, suggesting a possible immunotherapeutic target. Delivery of liposomal PKA inhibitor facilitates tumor regression and abrogates pro-tumoral TAM functions in mice. The therapeutic effect of targeting PKA is pronounced when combined with αCTLA-4 antibody, increasing cluster of differentiation 8 (CD8)+GranzymeB+ T cells by about 60-fold. Our findings demonstrate critical roles of TAM PKA-C in tumor progression and suggest that targeting PKA-C efficiently augments cancer treatment responses.
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5
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Harati R, Vandamme M, Blanchet B, Bardin C, Praz F, Hamoudi RA, Desbois-Mouthon C. Drug-Drug Interaction between Metformin and Sorafenib Alters Antitumor Effect in Hepatocellular Carcinoma Cells. Mol Pharmacol 2021; 100:32-45. [PMID: 33990407 DOI: 10.1124/molpharm.120.000223] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/09/2021] [Indexed: 01/21/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is one of the leading causes of cancer-related deaths worldwide. The multitarget inhibitor sorafenib is a first-line treatment of patients with advanced unresectable HCC. Recent clinical studies have evidenced that patients treated with sorafenib together with the antidiabetic drug metformin have a survival disadvantage compared with patients receiving sorafenib only. Here, we examined whether a clinically relevant dose of metformin (50 mg/kg per day) could influence the antitumoral effects of sorafenib (15 mg/kg per day) in a subcutaneous xenograft model of human HCC growth using two different sequences of administration, i.e., concomitant versus sequential dosing regimens. We observed that the administration of metformin 6 hours prior to sorafenib was significantly less effective in inhibiting tumor growth (15.4% tumor growth inhibition) than concomitant administration of the two drugs (59.5% tumor growth inhibition). In vitro experiments confirmed that pretreatment of different human HCC cell lines with metformin reduced the effects of sorafenib on cell viability, proliferation, and signaling. Transcriptomic analysis confirmed significant differences between xenografted tumors obtained under the concomitant and the sequential dosing regimens. Taken together, these observations call into question the benefit of parallel use of metformin and sorafenib in patients with advanced HCC and diabetes, as the interaction between the two drugs could ultimately compromise patient survival. SIGNIFICANCE STATEMENT: When drugs are administered sequentially, metformin alters the antitumor effect of sorafenib, the reference treatment for advanced hepatocellular carcinoma, in a preclinical murine xenograft model of liver cancer progression as well as in hepatic cancer cell lines. Defective activation of the AMP-activated protein kinase pathway as well as major transcriptomic changes are associated with the loss of the antitumor effect. These results echo recent clinical work reporting a poorer prognosis for patients with liver cancer who were cotreated with metformin and sorafenib.
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Affiliation(s)
- Rania Harati
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Marc Vandamme
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Benoit Blanchet
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Christophe Bardin
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Françoise Praz
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Rifat Akram Hamoudi
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
| | - Christèle Desbois-Mouthon
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy (R.H.), and Department of Clinical Sciences, College of Medicine (R.A.H), University of Sharjah, Sharjah, United Arab Emirates; Centre de Recherche Saint-Antoine (R.H., M.V., F.P., C.D.-M.) and Centre de Recherche des Cordeliers (C.D.-M.), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Paris, Paris, France; Département de Pharmacocinétique et Pharmacochimie, Hôpital Cochin, AP-HP, CARPEM, Paris, France (B.B., C.B.); UMR8038 CNRS, U1268 INSERM, Faculté de Pharmacie, Université de Paris, PRES Sorbonne Paris Cité, Paris, France (B.B); Centre National de la Recherche Scientifique, Paris, France (F.P.); and Division of Surgery and Interventional Science, UCL, London, United Kingdom (R.A.H.)
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6
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Ognjenovic NB, Bagheri M, Mohamed GA, Xu K, Chen Y, Mohamed Saleem MA, Brown MS, Nagaraj SH, Muller KE, Gerber SA, Christensen BC, Pattabiraman DR. Limiting Self-Renewal of the Basal Compartment by PKA Activation Induces Differentiation and Alters the Evolution of Mammary Tumors. Dev Cell 2020; 55:544-557.e6. [PMID: 33120014 DOI: 10.1016/j.devcel.2020.10.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 08/10/2020] [Accepted: 10/05/2020] [Indexed: 01/09/2023]
Abstract
Differentiation therapy utilizes our understanding of the hierarchy of cellular systems to pharmacologically induce a shift toward terminal commitment. While this approach has been a paradigm in treating certain hematological malignancies, efforts to translate this success to solid tumors have met with limited success. Mammary-specific activation of PKA in mouse models leads to aberrant differentiation and diminished self-renewing potential of the basal compartment, which harbors mammary repopulating cells. PKA activation results in tumors that are more benign, exhibiting reduced metastatic propensity, loss of tumor-initiating potential, and increased sensitivity to chemotherapy. Analysis of tumor histopathology revealed features of overt differentiation with papillary characteristics. Longitudinal single-cell profiling at the hyperplasia and tumor stages uncovered an altered path of tumor evolution whereby PKA curtails the emergence of aggressive subpopulations. Acting through the repression of SOX4, PKA activation promotes tumor differentiation and represents a possible adjuvant to chemotherapy for certain breast cancers.
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Affiliation(s)
- Nevena B Ognjenovic
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Meisam Bagheri
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Gadisti Aisha Mohamed
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Ke Xu
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Youdinghuan Chen
- Department of Epidemiology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | | | - Meredith S Brown
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Shivashankar H Nagaraj
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4001, Australia; School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD 4059, Australia; Translational Research Institute, Brisbane, QLD 4102, Australia
| | - Kristen E Muller
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA; Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA
| | - Scott A Gerber
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA
| | - Brock C Christensen
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA; Department of Epidemiology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Diwakar R Pattabiraman
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA.
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7
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Hsu YC, Chang YH, Chang GC, Ho BC, Yuan SS, Li YC, Zeng JW, Yu SL, Li KC, Yang PC, Chen HY. Tumor mutation burden and recurrent tumors in hereditary lung cancer. Cancer Med 2019; 8:2179-2187. [PMID: 30941903 PMCID: PMC6536970 DOI: 10.1002/cam4.2120] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/24/2019] [Accepted: 03/11/2019] [Indexed: 12/27/2022] Open
Abstract
Lung cancer is the leading cause of cancer death worldwide and cancer relapse accounts for the majority of cancer mortality. The mechanism is still unknown, especially in hereditary lung cancer without known actionable mutations. To identify genetic alternations involved in hereditary lung cancer and relapse is urgently needed. We collected genetic materials from a unique hereditary lung cancer patient's blood, first cancer tissue (T1), adjacent normal tissue (N1), relapse cancer tissue (T2), and adjacent normal tissue (N2) for whole genome sequencing. We identified specific mutations in T1 and T2, and attributed them to tumorigenesis and recurrence. These tumor specific variants were enriched in antigen presentation pathway. In addition, a lung adenocarcinoma cohort from the TCGA dataset was used to confirm our findings. Patients with high mutation burdens in tumor specific genes had decreased relapse‐free survival (P = 0.017, n = 186). Our study may provide important insight for designing immunotherapeutic treatment for hereditary lung cancer.
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Affiliation(s)
- Yi-Chiung Hsu
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Ya-Hsuan Chang
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Gee-Chen Chang
- Division of Chest Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.,Comprehensive Cancer Center, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Bing-Ching Ho
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shin-Sheng Yuan
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Yu-Cheng Li
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Jhih-Wun Zeng
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Sung-Liang Yu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ker-Chau Li
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan.,Department of Statistics, University of California Los Angeles, Los Angeles, California
| | - Pan-Chyr Yang
- College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsuan-Yu Chen
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
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8
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Giacomelli C, Daniele S, Romei C, Tavanti L, Neri T, Piano I, Celi A, Martini C, Trincavelli ML. The A 2B Adenosine Receptor Modulates the Epithelial- Mesenchymal Transition through the Balance of cAMP/PKA and MAPK/ERK Pathway Activation in Human Epithelial Lung Cells. Front Pharmacol 2018; 9:54. [PMID: 29445342 PMCID: PMC5797802 DOI: 10.3389/fphar.2018.00054] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/15/2018] [Indexed: 12/12/2022] Open
Abstract
The epithelial-mesenchymal transition (EMT) is a complex process in which cell phenotype switches from the epithelial to mesenchymal one. The deregulations of this process have been related with the occurrence of different diseases such as lung cancer and fibrosis. In the last decade, several efforts have been devoted in understanding the mechanisms that trigger and sustain this transition process. Adenosine is a purinergic signaling molecule that has been involved in the onset and progression of chronic lung diseases and cancer through the A2B adenosine receptor subtype activation, too. However, the relationship between A2BAR and EMT has not been investigated, yet. Herein, the A2BAR characterization was carried out in human epithelial lung cells. Moreover, the effects of receptor activation on EMT were investigated in the absence and presence of transforming growth factor-beta (TGF-β1), which has been known to promote the transition. The A2BAR activation alone decreased and increased the expression of epithelial markers (E-cadherin) and the mesenchymal one (Vimentin, N-cadherin), respectively, nevertheless a complete EMT was not observed. Surprisingly, the receptor activation counteracted the EMT induced by TGF-β1. Several intracellular pathways regulate the EMT: high levels of cAMP and ERK1/2 phosphorylation has been demonstrated to counteract and promote the transition, respectively. The A2BAR stimulation was able to modulated these two pathways, cAMP/PKA and MAPK/ERK, shifting the fine balance toward activation or inhibition of EMT. In fact, using a selective PKA inhibitor, which blocks the cAMP pathway, the A2BAR-mediated EMT promotion were exacerbated, and conversely the selective inhibition of MAPK/ERK counteracted the receptor-induced transition. These results highlighted the A2BAR as one of the receptors involved in the modulation of EMT process. Nevertheless, its activation is not enough to trigger a complete transition, its ability to affect different intracellular pathways could represent a mechanism at the basis of EMT maintenance/inhibition based on the extracellular microenvironment. Despite further investigations are needed, herein for the first time the A2BAR has been related to the EMT process, and therefore to the different EMT-related pathologies.
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Affiliation(s)
| | | | - Chiara Romei
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy.,Radiology Unit, University Hospital of Pisa, Pisa, Italy
| | - Laura Tavanti
- Pneumology Unit, Cardio-Thoracic Department, University Hospital of Pisa, Pisa, Italy
| | - Tommaso Neri
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Ilaria Piano
- Department of Pharmacy, University of Pisa, Pisa, Italy
| | - Alessandro Celi
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
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9
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Genomic Analysis of Pigmented Epithelioid Melanocytomas Reveals Recurrent Alterations in PRKAR1A, and PRKCA Genes. Am J Surg Pathol 2017; 41:1333-1346. [DOI: 10.1097/pas.0000000000000902] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Liu Y, Xu H, Geng Y, Xu D, Zhang L, Yang Y, Wei Z, Zhang B, Li S, Gao X, Wang R, Zhang X, Brann D, Yang F. Dibutyryl-cAMP attenuates pulmonary fibrosis by blocking myofibroblast differentiation via PKA/CREB/CBP signaling in rats with silicosis. Respir Res 2017; 18:38. [PMID: 28222740 PMCID: PMC5320641 DOI: 10.1186/s12931-017-0523-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 02/16/2017] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Myofibroblasts play a major role in the synthesis of extracellular matrix (ECM) and the stimulation of these cells is thought to play an important role in the development of silicosis. The present study was undertaken to investigate the anti-fibrotic effects of dibutyryl-cAMP (db-cAMP) on rats induced by silica. METHODS A HOPE MED 8050 exposure control apparatus was used to create the silicosis model. Rats were randomly divided into 4 groups: 1)controls for 16 w; 2)silicosis for 16 w; 3)db-cAMP pre-treatment; 4) db-cAMP post-treatment. Rat pulmonary fibroblasts were cultured in vitro and divided into 4 groups as follows: 1) controls; 2) 10-7mol/L angiotensin II (Ang II); 3) Ang II +10-4 mol/L db-cAMP; and 4) Ang II + db-cAMP+ 10-6 mol/L H89. Hematoxylin-eosin (HE), Van Gieson staining and immunohistochemistry (IHC) were performed to observe the histomorphology of lung tissue. The levels of cAMP were detected by enzyme immunoassay. Double-labeling for α-SMA with Gαi3, protein kinase A (PKA), phosphorylated cAMP-response element-binding protein (p-CREB), and p-Smad2/3 was identified by immunofluorescence staining. Protein levels were detected by Western blot analysis. The interaction between CREB-binding protein (CBP) and Smad2/3 and p-CREB were measured by co-immunoprecipitation (Co-IP). RESULTS Db-cAMP treatment reduced the number and size of silicosis nodules, inhibited myofibroblast differentiation, and extracellular matrix deposition in vitro and in vivo. In addition, db-cAMP regulated Gαs protein and inhibited expression of Gαi protein, which increased endogenous cAMP. Db-cAMP increased phosphorylated cAMP-response element-binding protein (p-CREB) via protein kinase A (PKA) signaling, and decreased nuclear p-Smad2/3 binding with CREB binding protein (CBP), which reduced activation of p-Smads in fibroblasts induced by Ang II. CONCLUSIONS This study showed an anti-silicotic effect of db-cAMP that was mediated via PKA/p-CREB/CBP signaling. Furthermore, the findings offer novel insight into the potential use of cAMP signaling for therapeutic strategies to treat silicosis.
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Affiliation(s)
- Yan Liu
- Basic Medical College, Hebei Medical University, No. 361 Zhongshan Road, Shijiazhuang city, Hebei province, China
| | - Hong Xu
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Yucong Geng
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Dingjie Xu
- Traditional Chinese Medicine College, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Lijuan Zhang
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Yi Yang
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Zhongqiu Wei
- Basic Medical College, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Bonan Zhang
- Basic Medical College, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Shifeng Li
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Xuemin Gao
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Ruimin Wang
- Medical Research Center, North China University of Science and Technology, Tangshan, Hebei, 063009, China
| | - Xianghong Zhang
- Basic Medical College, Hebei Medical University, No. 361 Zhongshan Road, Shijiazhuang city, Hebei province, China
| | - Darrell Brann
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Fang Yang
- Basic Medical College, Hebei Medical University, No. 361 Zhongshan Road, Shijiazhuang city, Hebei province, China.
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11
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Bandettini WP, Karageorgiadis AS, Sinaii N, Rosing DR, Sachdev V, Schernthaner-Reiter MH, Gourgari E, Papadakis GZ, Keil MF, Lyssikatos C, Carney JA, Arai AE, Lodish M, Stratakis CA. Growth hormone and risk for cardiac tumors in Carney complex. Endocr Relat Cancer 2016; 23:739-46. [PMID: 27535175 PMCID: PMC4991637 DOI: 10.1530/erc-16-0246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 07/15/2016] [Indexed: 11/08/2022]
Abstract
Carney complex (CNC) is a multiple neoplasia syndrome that is caused mostly by PRKAR1A mutations. Cardiac myxomas are the leading cause of mortality in CNC patients who, in addition, often develop growth hormone (GH) excess. We studied patients with CNC, who were observed for over a period of 20 years (1995-2015) for the development of both GH excess and cardiac myxomas. GH secretion was evaluated by standard testing; dedicated cardiovascular imaging was used to detect cardiac abnormalities. Four excised cardiac myxomas were tested for the expression of insulin-like growth factor-1 (IGF-1). A total of 99 CNC patients (97 with a PRKAR1A mutation) were included in the study with a mean age of 25.8 ± 16.6 years at presentation. Over an observed mean follow-up of 25.8 years, 60% of patients with GH excess (n = 46) developed a cardiac myxoma compared with only 36% of those without GH excess (n = 54) (P = 0.016). Overall, patients with GH excess were also more likely to have a tumor vs those with normal GH secretion (OR: 2.78, 95% CI: 1.23-6.29; P = 0.014). IGF-1 mRNA and protein were higher in CNC myxomas than in normal heart tissue. We conclude that the development of cardiac myxomas in CNC may be associated with increased GH secretion, in a manner analogous to the association between fibrous dysplasia and GH excess in McCune-Albright syndrome, a condition similar to CNC. We speculate that treatment of GH excess in patients with CNC may reduce the likelihood of cardiac myxoma formation and/or recurrence of this tumor.
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Affiliation(s)
- W Patricia Bandettini
- National HeartLung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Alexander S Karageorgiadis
- National Institute of Child Health and Human Development (NICHD)NIH, Bethesda, Maryland, USA Department of PediatricsGeorgetown University Hospital, Washington, District of Columbia, USA
| | - Ninet Sinaii
- Biostatistics and Clinical Epidemiology ServiceClinical Center, NIH, Bethesda, Maryland, USA
| | - Douglas R Rosing
- National HeartLung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Vandana Sachdev
- National HeartLung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | | | - Evgenia Gourgari
- National Institute of Child Health and Human Development (NICHD)NIH, Bethesda, Maryland, USA Department of PediatricsGeorgetown University Hospital, Washington, District of Columbia, USA
| | - Georgios Z Papadakis
- Department of Radiology and Imaging SciencesClinical Center, NIH, Bethesda, Maryland, USA
| | - Meg F Keil
- National Institute of Child Health and Human Development (NICHD)NIH, Bethesda, Maryland, USA
| | - Charalampos Lyssikatos
- National Institute of Child Health and Human Development (NICHD)NIH, Bethesda, Maryland, USA
| | - J Aidan Carney
- Department of Laboratory Medicine and PathologyMayo Clinic, Rochester, Minnesota, USA
| | - Andrew E Arai
- National HeartLung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Maya Lodish
- National Institute of Child Health and Human Development (NICHD)NIH, Bethesda, Maryland, USA
| | - Constantine A Stratakis
- National Institute of Child Health and Human Development (NICHD)NIH, Bethesda, Maryland, USA
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12
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Gooding AJ, Schiemann WP. Harnessing protein kinase A activation to induce mesenchymal-epithelial programs to eliminate chemoresistant, tumor-initiating breast cancer cells. Transl Cancer Res 2016; 5:S226-S232. [PMID: 28680830 PMCID: PMC5495186 DOI: 10.21037/tcr.2016.08.09] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Alex J Gooding
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106
| | - William P Schiemann
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106
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13
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A siRNA screen reveals the prosurvival effect of protein kinase A activation in conditions of unresolved endoplasmic reticulum stress. Cell Death Differ 2016; 23:1670-80. [PMID: 27341185 DOI: 10.1038/cdd.2016.59] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 05/10/2016] [Accepted: 05/30/2016] [Indexed: 11/08/2022] Open
Abstract
The endoplasmic reticulum (ER) has a crucial role in the proper folding of proteins that are synthesized in the secretory pathway. Physiological and pathological conditions can induce accumulation of mis- or unfolded proteins in the ER lumen and thereby generate a state of cellular stress known as ER stress. The unfolded protein response aims at restoring protein-folding homeostasis, but turns into a toxic signal when ER stress is too severe or prolonged. ER stress-induced cellular dysfunction and death is associated with several human diseases, but the molecular mechanisms regulating death under unresolved ER stress are still unclear. We performed a siRNA-based screen to identify new regulators of ER stress-induced death and found that repression of the Carney complex-associated protein PRKAR1A specifically protected the cells from ER stress-induced apoptosis, and not from apoptosis induced by etoposide or TNF. We demonstrate that the protection results from PKA activation and associate it, at least in part, with the phosphorylation-mediated inhibition of the PKA substrate Drp1 (dynamin-related protein 1). Our results therefore provide new information on the complex regulation of cellular death under ER stress conditions and bring new insights on the conditions that regulate the pro- versus anti-death functions of PKA.
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14
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Del Gobbo A, Peverelli E, Treppiedi D, Lania A, Mantovani G, Ferrero S. Expression of protein kinase A regulatory subunits in benign and malignant human thyroid tissues: A systematic review. Exp Cell Res 2016; 346:85-90. [PMID: 27321957 DOI: 10.1016/j.yexcr.2016.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/17/2016] [Accepted: 06/08/2016] [Indexed: 11/30/2022]
Abstract
In this review, we discuss the molecular mechanisms and prognostic implications of the protein kinase A (PKA) signaling pathway in human tumors, with special emphasis on the malignant thyroid. The PKA signaling pathway is differentially activated by the expression of regulatory subunits 1 (R1) and 2 (R2), whose levels change during development, differentiation, and neoplastic transformation. Following the identification of gene mutations within the PKA regulatory subunit R1A (PRKAR1A) that cause Carney complex-associated neoplasms, several investigators have studied PRKAR1A expression in sporadic thyroid tumors. The PKA regulatory subunit R2B (PRKAR2B) is highly expressed in benign, as well as in malignant differentiated and undifferentiated lesions. PRKAR1A is highly expressed in follicular adenomas and malignant lesions with a statistically significant gradient between benign and malignant tumors; however, it is not expressed in hyperplastic nodules. Although the importance of PKA in human malignancy outcomes is not completely understood, PRKAR1A expression correlates with tumor dimension in malignant lesions. Additional studies are needed to determine whether a relationship exists between PKA subunit expression and clinical outcomes, particularly in undifferentiated tumors. In conclusion, the R1A subunit might be a good molecular candidate for the targeted treatment of malignant thyroid tumors.
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Affiliation(s)
- Alessandro Del Gobbo
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Erika Peverelli
- Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Donatella Treppiedi
- Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Andrea Lania
- Endocrine Unit, IRCCS Humanitas Research Hospital, University of Milan, Milan, Italy
| | - Giovanna Mantovani
- Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Stefano Ferrero
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy; Department of Biomedical, Surgical and Dental Sciences, University of Milan Medical School, Milan, Italy.
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15
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Pattabiraman DR, Bierie B, Kober KI, Thiru P, Krall JA, Zill C, Reinhardt F, Tam WL, Weinberg RA. Activation of PKA leads to mesenchymal-to-epithelial transition and loss of tumor-initiating ability. Science 2016; 351:aad3680. [PMID: 26941323 DOI: 10.1126/science.aad3680] [Citation(s) in RCA: 242] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The epithelial-to-mesenchymal transition enables carcinoma cells to acquire malignancy-associated traits and the properties of tumor-initiating cells (TICs). TICs have emerged in recent years as important targets for cancer therapy, owing to their ability to drive clinical relapse and enable metastasis. Here, we propose a strategy to eliminate mesenchymal TICs by inducing their conversion to more epithelial counterparts that have lost tumor-initiating ability. We report that increases in intracellular levels of the second messenger, adenosine 3',5'-monophosphate, and the subsequent activation of protein kinase A (PKA) induce a mesenchymal-to-epithelial transition (MET) in mesenchymal human mammary epithelial cells. PKA activation triggers epigenetic reprogramming of TICs by the histone demethylase PHF2, which promotes their differentiation and loss of tumor-initiating ability. This study provides proof-of-principle for inducing an MET as differentiation therapy for TICs and uncovers a role for PKA in enforcing and maintaining the epithelial state.
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Affiliation(s)
| | - Brian Bierie
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | | | - Prathapan Thiru
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Jordan A Krall
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Christina Zill
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Ferenc Reinhardt
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Wai Leong Tam
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA. Genome Institute of Singapore, 60 Biopolis Street, Singapore. Cancer Science Institute of Singapore, 14 Medical Drive, Singapore
| | - Robert A Weinberg
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA. Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Ludwig Center for Molecular Oncology at MIT, Cambridge, MA 02142, USA.
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16
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Loss of Prkar1a leads to Bcl-2 family protein induction and cachexia in mice. Cell Death Differ 2014; 21:1815-24. [PMID: 25012505 DOI: 10.1038/cdd.2014.98] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 06/07/2014] [Accepted: 06/10/2014] [Indexed: 11/08/2022] Open
Abstract
Loss of function mutations in the Prkar1a gene are the cause of most cases of Carney complex disorder. Defects in Prkar1a are thought to cause hyper-activation of PKA signalling, which drives neoplastic transformation, and Prkar1a is therefore considered to be a tumour suppressor. Here we show that loss of Prkar1a in genetically modified mice caused transcriptional activation of several proapoptotic Bcl-2 family members and thereby caused cell death. Interestingly, combined loss of Bim and Prkar1a increased colony formation of fibroblasts in culture and promoted their growth as tumours in immune-deficient mice. Apart from inducing apoptosis, systemic deletion of Prkar1a caused cachexia with muscle loss, macrophage activation and increased lipolysis as well as serum triglyceride levels. Loss of single allele of Prkar1a did not enhance tumour development in a skin cancer model, but surprisingly, when combined with the loss of Bim, caused a significant delay in tumorigenesis and this was associated with upregulation of other BH3-only proteins, PUMA and NOXA. These results show that loss of Prkar1a can only promote tumorigenesis when Prkar1a-mediated apoptosis is somehow countered.
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17
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PKA signaling drives mammary tumorigenesis through Src. Oncogene 2014; 34:1160-73. [PMID: 24662820 DOI: 10.1038/onc.2014.41] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 12/20/2013] [Accepted: 12/24/2013] [Indexed: 12/30/2022]
Abstract
Protein kinase A (PKA) hyperactivation causes hereditary endocrine neoplasias; however, its role in sporadic epithelial cancers is unknown. Here, we show that heightened PKA activity in the mammary epithelium generates tumors. Mammary-restricted biallelic ablation of Prkar1a, which encodes for the critical type-I PKA regulatory subunit, induced spontaneous breast tumors characterized by enhanced type-II PKA activity. Downstream of this, Src phosphorylation occurs at residues serine-17 and tyrosine-416 and mammary cell transformation is driven through a mechanism involving Src signaling. The phenotypic consequences of these alterations consisted of increased cell proliferation and, accordingly, expansion of both luminal and basal epithelial cell populations. In human breast cancer, low PRKAR1A/high SRC expression defines basal-like and HER2 breast tumors associated with poor clinical outcome. Together, the results of this study define a novel molecular mechanism altered in breast carcinogenesis and highlight the potential strategy of inhibiting SRC signaling in treating this cancer subtype in humans.
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18
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CREB-binding protein (CBP) regulates β-adrenoceptor (β-AR)-mediated apoptosis. Cell Death Differ 2013; 20:941-52. [PMID: 23579242 DOI: 10.1038/cdd.2013.29] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Catecholamines regulate the β-adrenoceptor/cyclic AMP-regulated protein kinase A (cAMP/PKA) pathway. Deregulation of this pathway can cause apoptotic cell death and is implicated in a range of human diseases, such as neuronal loss during aging, cardiomyopathy and septic shock. The molecular mechanism of this process is, however, only poorly understood. Here we demonstrate that the β-adrenoceptor/cAMP/PKA pathway triggers apoptosis through the transcriptional induction of the pro-apoptotic BH3-only Bcl-2 family member Bim in tissues such as the thymus and the heart. In these cell types, the catecholamine-mediated apoptosis is abrogated by loss of Bim. Induction of Bim is driven by the transcriptional co-activator CBP (CREB-binding protein) together with the proto-oncogene c-Myc. Association of CBP with c-Myc leads to altered histone acetylation and methylation pattern at the Bim promoter site. Our findings have implications for understanding pathophysiology associated with a deregulated neuroendocrine system and for developing novel therapeutic strategies for these diseases.
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19
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Hung SW, Chiu CF, Chen TA, Chu CL, Huang CC, Shyur LF, Liang CM, Liang SM. Recombinant viral protein VP1 suppresses HER-2 expression and migration/metastasis of breast cancer. Breast Cancer Res Treat 2012; 136:89-105. [PMID: 22983836 DOI: 10.1007/s10549-012-2238-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 08/28/2012] [Indexed: 11/30/2022]
Abstract
Breast cancer is one of the most common cancers in women worldwide and metastasis is the major cause of breast cancer death. Development of new therapeutic agents for inhibiting breast cancer metastasis is therefore an urgent need. We previously demonstrated that recombinant DNA-derived viral capsid protein VP1 (rVP1) of foot-and-mouth disease virus-induced apoptosis of MCF-7 breast cancer cells in vitro. Here, we investigated whether rVP1 exhibits any inhibitory effects on migration/metastasis and human epidermal growth factor receptor 2 (HER-2), a well-known biomarker for poor prognosis of breast cancer. The effects of rVP1 on cancer cell migration/invasion and metastasis were evaluated using Transwell migration assay and animal cancer models of metastasis. Western blotting, RT-PCR, flow cytometry, immunohistochemistry, and immunofluorescence staining techniques were used to investigate the effects of rVP1 on HER-2 and signal transduction mediators. Non-cytotoxic concentrations of rVP1-induced mesenchymal-epithelial transition and significantly suppressed AP-2α and HER-2 expression as well as the migration and invasion of a variety of breast cancer cell lines in a β1-integrin-dependent manner in vitro. Gross and histopathologic examinations showed that rVP1 also suppressed metastasis of several breast cancer cell lines, including HER-2-overexpressing SK-BR-3 and BT-474 cells to lung, liver, or peripheral lymph node in orthotopic allograft/xenograft murine models. In addition, rVP1 significantly prolonged survival in breast cancer-bearing mice. Notably, no apparent side effects of rVP1 were detected, as shown by normal complete blood count levels and serum biochemistry profiles, including AST, ALT, BUN, and creatine. This study demonstrates that rVP1 suppresses the migration, invasion, and metastasis of breast cancer cells via binding to β1 integrin receptor and down-regulation of AP-2α and HER-2 expression. The effectiveness of rVP1 on inhibiting migration/metastasis of breast cancer and HER-2 expression suggests that it may be suitable for serving as potential therapeutics for metastatic breast cancer particularly HER-2-overexpressing cancer.
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Affiliation(s)
- Shao-Wen Hung
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
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20
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Pringle DR, Yin Z, Lee AA, Manchanda PK, Yu L, Parlow AF, Jarjoura D, La Perle KMD, Kirschner LS. Thyroid-specific ablation of the Carney complex gene, PRKAR1A, results in hyperthyroidism and follicular thyroid cancer. Endocr Relat Cancer 2012; 19:435-46. [PMID: 22514108 PMCID: PMC3667702 DOI: 10.1530/erc-11-0306] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Thyroid cancer is the most common endocrine malignancy in the population, and the incidence of this cancer is increasing at a rapid rate. Although genetic analysis of papillary thyroid cancer (PTC) has identified mutations in a large percentage of patients, the genetic basis of follicular thyroid cancer (FTC) is less certain. Thyroid cancer, including both PTC and FTC, has been observed in patients with the inherited tumor predisposition Carney complex, caused by mutations in PRKAR1A. In order to investigate the role of loss of PRKAR1A in thyroid cancer, we generated a tissue-specific knockout of Prkar1a in the thyroid. We report that the resulting mice are hyperthyroid and developed follicular thyroid neoplasms by 1 year of age, including FTC in over 40% of animals. These thyroid tumors showed a signature of pathway activation different from that observed in other models of thyroid cancer. In vitro cultures of the tumor cells indicated that Prkar1a-null thyrocytes exhibited growth factor independence and suggested possible new therapeutic targets. Overall, this work represents the first report of a genetic mutation known to cause human FTC that exhibits a similar phenotype when modeled in the mouse. In addition to our knowledge of the mechanisms of human follicular thyroid tumorigenesis, this model is highly reproducible and may provide a viable mechanism for the further clinical development of therapies aimed at FTC.
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Affiliation(s)
- Daphne R. Pringle
- Department of Molecular, Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH, 43210
| | - Zhirong Yin
- Department of Molecular, Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH, 43210
| | - Audrey A. Lee
- Department of Molecular, Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH, 43210
| | - Parmeet K. Manchanda
- Department of Molecular, Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH, 43210
| | - Lianbo Yu
- Center for Biostatistics, The Ohio State University, Columbus, OH, 43210
| | - Alfred F. Parlow
- National Hormone and Peptide Program, Harbor-UCLA Medical Center, Torrance, California 90509
| | - David Jarjoura
- Center for Biostatistics, The Ohio State University, Columbus, OH, 43210
| | - Krista M. D. La Perle
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, 43210
| | - Lawrence S. Kirschner
- Department of Molecular, Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH, 43210
- Division of Endocrinology, Diabetes and Metabolism, The Ohio State University, Columbus, OH, 43210
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21
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Wang YX, Zhao L, Wang XY, Liu CM, Yu SG. Association between E-cadherin (CDH1) polymorphisms and papillary thyroid carcinoma risk in Han Chinese population. Endocrine 2012; 41:526-31. [PMID: 22194161 DOI: 10.1007/s12020-011-9582-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 12/03/2011] [Indexed: 12/22/2022]
Abstract
The aim of this study is to investigate the associations between E-cadherin gene (CDH1) polymorphisms and papillary thyroid carcinoma (PTC) risk predisposition. We undertook a case-control study to analyze three CDH1 polymorphisms (+54T>C, -160C>A, and -347G→GA) in an Han Chinese population, by extraction of genomic DNA from the peripheral blood of 98 patients with PTC and 176 control participants, and performed CDH1 genotyping using DNA sequencing. The obtained results indicated that overall, no statistically significant association was observed in +54T>C. Nevertheless, -347G→GA genotype was at increased risk of PTC (P = 0.001; odds ratio (OR) = 2.12, CI 95%:1.24-3.34). Furthermore, -347GA/GA genotype thyroid cancers were more significantly common in patients with tumor size of ≥20 mm than G or G/GA genotypes PTC and in cases of advanced T stage. However, -160C>A genotype demonstrated a protective effect in PTCs (P = 0.006; OR = 0.59, CI 95%: 0.42-0.87). These findings led us to conclude that polymorphism in -347G→GA was observed to be associated with susceptibility of PTC. However, -160C>A polymorphism indicated to play a protective role in susceptibility to PTC. Nevertheless, further investigation with a larger sample size is needed to support our results.
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Affiliation(s)
- Ying-Xue Wang
- Department of Endocrinology, School of Clinical Medicine, Binzhou Medical University, No. 661, Yellow-River Second Street, Binzhou 256603, China.
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22
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Yin Z, Pringle DR, Jones GN, Kelly KM, Kirschner LS. Differential role of PKA catalytic subunits in mediating phenotypes caused by knockout of the Carney complex gene Prkar1a. Mol Endocrinol 2011; 25:1786-93. [PMID: 21852354 DOI: 10.1210/me.2011-1008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Carney complex is an inherited tumor predisposition caused by activation of the cAMP-dependent protein kinase [protein kinase A (PKA)] resulting from mutation of the PKA-regulatory subunit gene PRKAR1A. Myxomas and tumors in cAMP-responsive tissues are cardinal features of this syndrome, which is unsurprising given the important role played by PKA in modulating cell growth and function. Previous studies demonstrated that cardiac-specific knockout of Prkar1a causes embryonic heart failure and myxomatous degeneration in the heart, whereas limited Schwann cell-specific knockout of the gene causes schwannoma formation. In this study, we sought to determine the role of PKA activation in this phenotype by using genetic means to reduce PKA enzymatic activity. To accomplish this goal, we introduced null alleles of the PKA catalytic subunits Prkaca (Ca) or Prkacb (Cb) into the Prkar1a-cardiac knockout (R1a-CKO) or limited Schwann cell knockout (R1a-TEC3KO) line. Heterozygosity for Prkaca rescued the embryonic lethality of the R1a-CKO, although mice had a shorter than normal lifespan and died from cardiac failure with atrial thrombosis. In contrast, heterozygosity for Prkacb only enabled the mice to survive 1 extra day during embryogenesis. Biochemical analysis indicated that reduction of Ca markedly reduced PKA activity in embryonic hearts, whereas reduction of Cb had minimal effects. In R1a-TEC3KO mice, tumorigenesis was completely suppressed by a heterozygosity for Prkaca, and by more than 80% by heterozygosity for Prkacb. These data suggest that both developmental and tumor phenotypes caused by Prkar1a mutation result from excess PKA activity due to PKA-Ca.
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Affiliation(s)
- Zhirong Yin
- Department of Molecular Virology, Immunology, and Medical Genetics, Ohio State University, Columbus, Ohio 43210, USA
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Prolonged mammosphere culture of MCF-7 cells induces an EMT and repression of the estrogen receptor by microRNAs. Breast Cancer Res Treat 2011; 132:75-85. [PMID: 21553120 DOI: 10.1007/s10549-011-1534-y] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 04/16/2011] [Indexed: 12/21/2022]
Abstract
Mammosphere culture has been used widely for the enrichment of mammary epithelial stem cells and breast cancer stem cells (CSCs). Epithelial-to-mesenchymal transition (EMT) also induces stem cell features in normal and transformed mammary cells. We examined whether mammosphere culture conditions per se induced EMT in the epithelial MCF-7 breast cancer cell line. MCF-7 cells were cultured as mammospheres for 5 weeks, with dispersal and reseeding at the end of each week. This mammosphere culture induced a complete EMT by 3 weeks. Return of the cells to standard adherent culture conditions in serum-supplemented media generated a cell population (called MCF-7(M) cells), which displays a stable mesenchymal and CSC-like CD(44+)/CD(24-/low) phenotype. EMT was accompanied by a stable, marked increase in EMT-associated transcription factors and mesenchymal markers, and a decrease in epithelial markers and estrogen receptor α (ERα). MCF-7(M) cells showed increased motility, proliferation and chemoresistance in vitro, and produced larger tumors in immunodeficient mice with or without estrogen supplementation. MicroRNA analysis showed suppression of miR-200c, miR-203, and miR-205; and increases in miR-222 and miR-221. Antisense hairpin RNA inhibitor targeting miR-221 resulted in re-expression of ERα in MCF-7(M) cells. This study provides the first example of mammosphere culture conditions inducing EMT and of EMT regulating microRNAs that target ERα.
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Alternate protein kinase A activity identifies a unique population of stromal cells in adult bone. Proc Natl Acad Sci U S A 2010; 107:8683-8. [PMID: 20421483 DOI: 10.1073/pnas.1003680107] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A population of stromal cells that retains osteogenic capacity in adult bone (adult bone stromal cells or aBSCs) exists and is under intense investigation. Mice heterozygous for a null allele of prkar1a (Prkar1a(+/-)), the primary receptor for cyclic adenosine monophosphate (cAMP) and regulator of protein kinase A (PKA) activity, developed bone lesions that were derived from cAMP-responsive osteogenic cells and resembled fibrous dysplasia (FD). Prkar1a(+/-) mice were crossed with mice that were heterozygous for catalytic subunit Calpha (Prkaca(+/-)), the main PKA activity-mediating molecule, to generate a mouse model with double heterozygosity for prkar1a and prkaca (Prkar1a(+/-)Prkaca(+/-)). Unexpectedly, Prkar1a(+/-)Prkaca(+/-) mice developed a greater number of osseous lesions starting at 3 months of age that varied from the rare chondromas in the long bones and the ubiquitous osteochondrodysplasia of vertebral bodies to the occasional sarcoma in older animals. Cells from these lesions originated from an area proximal to the growth plate, expressed osteogenic cell markers, and showed higher PKA activity that was mostly type II (PKA-II) mediated by an alternate pattern of catalytic subunit expression. Gene expression profiling confirmed a preosteoblastic nature for these cells but also showed a signature that was indicative of mesenchymal-to-epithelial transition and increased Wnt signaling. These studies show that a specific subpopulation of aBSCs can be stimulated in adult bone by alternate PKA and catalytic subunit activity; abnormal proliferation of these cells leads to skeletal lesions that have similarities to human FD and bone tumors.
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Landry CS, Waguespack SG, Perrier ND. Surgical management of nonmultiple endocrine neoplasia endocrinopathies: state-of-the-art review. Surg Clin North Am 2009; 89:1069-89. [PMID: 19836485 DOI: 10.1016/j.suc.2009.06.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The development of genetic testing has given patients with familial endocrine diseases the opportunity to be identified earlier in life. The importance of this technological advancement cannot be underestimated, as some of these heritable diseases have significant potential for malignancy. This article focuses on the identification and surgical management of familial endocrinopathies of the thyroid, parathyroid, adrenal glands, and pancreas. Familial endocrinopathies discussed include hereditary nonmedullary carcinoma of the thyroid, Cowden disease, familial adenomatous polyposis, Carney complex, Werner syndrome, familial medullary thyroid carcinoma, Pendred syndrome, hereditary hyperparathyroidism jaw-tumor syndrome, familial isolated hyperparathyroidism, Beckwith- Wiedemann syndrome, Li-Fraumeni syndrome, neurofibromatosis I, von Hippel-Lindau disease, and tuberous sclerosis.
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Affiliation(s)
- Christine S Landry
- Department of Surgical Oncology, Unit 444, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
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Kashikar ND, Reiner J, Datta A, Datta PK. Serine threonine receptor-associated protein (STRAP) plays a role in the maintenance of mesenchymal morphology. Cell Signal 2009; 22:138-49. [PMID: 19781628 DOI: 10.1016/j.cellsig.2009.09.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 09/14/2009] [Indexed: 12/20/2022]
Abstract
The stromal tissue, made of extracellular matrix and mesenchymal cells, is vital for the functional design of all complex tissues. Fibroblasts are key components of stromal tissue and play a crucial role during organ development, wound repair, angiogenesis and fibrosis. We have previously reported the identification of a novel WD-domain protein, STRAP(1) that inhibits transforming growth factor-beta (TGF-beta) signaling and enhances tumorigenicity via TGF-beta-dependent and TGF-beta-independent mechanisms. Here, we report, for the first time, that deletion of STRAP from Mouse Embryonic Fibroblasts (MEFs) results in a loss of mesenchymal morphology. These cells lose their spindle shape and exhibit features of an epithelial morphology. Gene expression profiling has confirmed that deletion of STRAP affects expression of sets of genes important for diverse functions including cell-cell adhesion and cell polarization, and upregulates E-cadherin expression leading to the formation of adherens junctions, subsequent localization of beta-catenin to the cell membrane and downregulation of the mesenchymal markers like LEF1 (lymphoid enhancer-binding factor 1). Upregulation of WT1 (Wilms tumor homolog 1) in STRAP null MEFs plays a role in E-cadherin induction. Finally, stable expression of STRAP in these cells results in a loss of WT1 and E-cadherin expressions, and a reversal from epithelial to the mesenchymal morphology. Thus, these results provide a novel TGF-beta-independent function of STRAP and describe a mechanism for the role of STRAP in the maintenance of mesenchymal morphology.
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Affiliation(s)
- Nilesh D Kashikar
- Department of Surgery and Cancer Biology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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Kirschner LS. Use of mouse models to understand the molecular basis of tissue-specific tumorigenesis in the Carney complex. J Intern Med 2009; 266:60-8. [PMID: 19522826 DOI: 10.1111/j.1365-2796.2009.02114.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Carney complex (CNC) is an autosomal dominant, multiple endocrine neoplasia syndrome comprised of spotty skin pigmentation, myxomatosis, endocrine tumours and schwannomas. The majority of cases are due to inactivating mutations in PRKAR1A, the gene encoding the type 1A regulatory subunit of the 3',5'-cyclic adenosine monophosphate (cAMP)-dependent protein kinase, PKA (protein kinase A). In order to understand the molecular basis for tumorigenesis associated with PRKAR1A mutations, we have developed conventional and conditional Prkar1a knockout (KO) mice as well as primary cell culture models corresponding to these genetic manipulations. At the biochemical level, removal of Prkar1a from cells causes enhanced PKA activity, the same effect which has been observed in tumours isolated from CNC patients. Mice heterozygous for Prkar1a mutations (the exact genetic model for CNC patients) are born at expected frequencies and are tumour prone, developing neoplasms in cAMP-responsive cell types such as Schwann cells, osteoblasts and thyrocytes. In order to understand the basis of tissue-specific tumour formation, we have created tissue-specific KOs of the gene from three different tissues: the neural crest (Schwann cells), the pituitary gland and the heart. In the neural crest and the pituitary, ablation of Prkar1a leads to excess proliferation and tumorigenesis, whereas the same manipulation in developing cardiomyocytes leads to reduced proliferation and embryonic demise. The KO hearts also exhibit myxomatous changes suggesting a connection between PKA activation and myxomagenesis, although the nature of this relationship has not yet been determined. This work confirms the role of Prkar1a as a tissue-specific tumour suppressor, and ongoing work is focused on identifying the key downstream signalling targets affected by dysregulation of PKA.
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Affiliation(s)
- L S Kirschner
- Division of Endocrinology, Diabetes and Metabolism and Human Cancer Genetics Program, The Ohio State University, 544 TMRF, 420 W 12th Ave, Columbus, OH 43210, USA.
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Regulation of actin function by protein kinase A-mediated phosphorylation of Limk1. EMBO Rep 2009; 10:599-605. [PMID: 19424295 DOI: 10.1038/embor.2009.58] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 02/20/2009] [Accepted: 02/25/2009] [Indexed: 11/09/2022] Open
Abstract
Proper regulation of the cAMP-dependent protein kinase (protein kinase A, PKA) is necessary for cellular homeostasis, and dysregulation of this kinase is crucial in human disease. Mouse embryonic fibroblasts (MEFs) lacking the PKA regulatory subunit Prkar1a show altered cell morphology and enhanced migration. At the molecular level, these cells showed increased phosphorylation of cofilin, a crucial modulator of actin dynamics, and these changes could be mimicked by stimulating the activity of PKA. Previous studies of cofilin have shown that it is phosphorylated primarily by the LIM domain kinases Limk1 and Limk2, which are under the control of the Rho GTPases and their downstream effectors. In Prkar1a(-/-) MEFs, neither Rho nor Rac was activated; rather, we showed that PKA could directly phosphorylate Limk1 and thus enhance the phosphorylation of cofilin. These data indicate that PKA is crucial in cell morphology and migration through its ability to modulate directly the activity of LIM kinase.
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