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Singh K, Maity P, Krug L, Meyer P, Treiber N, Lucas T, Basu A, Kochanek S, Wlaschek M, Geiger H, Scharffetter-Kochanek K. Superoxide anion radicals induce IGF-1 resistance through concomitant activation of PTP1B and PTEN. EMBO Mol Med 2015; 7:59-77. [PMID: 25520316 PMCID: PMC4309668 DOI: 10.15252/emmm.201404082] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The evolutionarily conserved IGF-1 signalling pathway is associated with longevity, metabolism, tissue homeostasis, and cancer progression. Its regulation relies on the delicate balance between activating kinases and suppressing phosphatases and is still not very well understood. We report here that IGF-1 signalling in vitro and in a murine ageing model in vivo is suppressed in response to accumulation of superoxide anions () in mitochondria, either by chemical inhibition of complex I or by genetic silencing of -dismutating mitochondrial Sod2. The -dependent suppression of IGF-1 signalling resulted in decreased proliferation of murine dermal fibroblasts, affected translation initiation factors and suppressed the expression of α1(I), α1(III), and α2(I) collagen, the hallmarks of skin ageing. Enhanced led to activation of the phosphatases PTP1B and PTEN, which via dephosphorylation of the IGF-1 receptor and phosphatidylinositol 3,4,5-triphosphate dampened IGF-1 signalling. Genetic and pharmacologic inhibition of PTP1B and PTEN abrogated -induced IGF-1 resistance and rescued the ageing skin phenotype. We thus identify previously unreported signature events with , PTP1B, and PTEN as promising targets for drug development to prevent IGF-1 resistance-related pathologies.
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Affiliation(s)
- Karmveer Singh
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany
| | - Pallab Maity
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany
| | - Linda Krug
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany
| | - Patrick Meyer
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany
| | - Nicolai Treiber
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany
| | - Tanja Lucas
- Department of Gene Therapy, University of Ulm, Ulm, Germany
| | - Abhijit Basu
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany
| | | | - Meinhard Wlaschek
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany
| | - Hartmut Geiger
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany Institute of Molecular Medicine and Stem Cell Aging, University of Ulm, Ulm, Germany Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, USA
| | - Karin Scharffetter-Kochanek
- Department of Dermatology and Allergic Diseases, University of Ulm, Ulm, Germany Aging Research Center (ARC), Ulm, Germany
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Aune SE, Herr DJ, Kutz CJ, Menick DR. Histone Deacetylases Exert Class-Specific Roles in Conditioning the Brain and Heart Against Acute Ischemic Injury. Front Neurol 2015; 6:145. [PMID: 26175715 PMCID: PMC4485035 DOI: 10.3389/fneur.2015.00145] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 06/15/2015] [Indexed: 12/12/2022] Open
Abstract
Ischemia-reperfusion (IR) injury comprises a significant portion of morbidity and mortality from heart and brain diseases worldwide. This enduring clinical problem has inspired myriad reports in the scientific literature of experimental interventions seeking to elucidate the pathology of IR injury. Elective cardiac surgery presents perhaps the most viable scenario for protecting the heart and brain from IR injury due to the opportunity to condition the organs prior to insult. The physiological parameters for the preconditioning of vital organs prior to insult through mechanical and pharmacological maneuvers have been heavily examined. These investigations have revealed new insights into how preconditioning alters cellular responses to IR injury. However, the promise of preconditioning remains unfulfilled at the clinical level, and research seeking to implicate cell signals essential to this protection continues. Recent discoveries in molecular biology have revealed that gene expression can be controlled through posttranslational modifications, without altering the chemical structure of the genetic code. In this scenario, gene expression is repressed by enzymes that cause chromatin compaction through catalytic removal of acetyl moieties from lysine residues on histones. These enzymes, called histone deacetylases (HDACs), can be inhibited pharmacologically, leading to the de-repression of protective genes. The discovery that HDACs can also alter the function of non-histone proteins through posttranslational deacetylation has expanded the potential impact of HDAC inhibitors for the treatment of human disease. HDAC inhibitors have been applied in a very small number of experimental models of IR. However, the scientific literature contains an increasing number of reports demonstrating that HDACs converge on preconditioning signals in the cell. This review will describe the influence of HDACs on major preconditioning signaling pathways in the heart and brain.
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Affiliation(s)
- Sverre E Aune
- Gazes Cardiac Research Institute, Medical University of South Carolina , Charleston, SC , USA
| | - Daniel J Herr
- Gazes Cardiac Research Institute, Medical University of South Carolina , Charleston, SC , USA
| | - Craig J Kutz
- Gazes Cardiac Research Institute, Medical University of South Carolina , Charleston, SC , USA
| | - Donald R Menick
- Gazes Cardiac Research Institute, Medical University of South Carolina , Charleston, SC , USA
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Hair BY, Xu Z, Kirk EL, Harlid S, Sandhu R, Robinson WR, Wu MC, Olshan AF, Conway K, Taylor JA, Troester MA. Body mass index associated with genome-wide methylation in breast tissue. Breast Cancer Res Treat 2015; 151:453-63. [PMID: 25953686 PMCID: PMC4474159 DOI: 10.1007/s10549-015-3401-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 04/21/2015] [Indexed: 01/04/2023]
Abstract
Gene expression studies indicate that body mass index (BMI) is associated with molecular pathways involved in inflammation, insulin-like growth factor activation, and other carcinogenic processes in breast tissue. The goal of this study was to determine whether BMI is associated with gene methylation in breast tissue and to identify pathways that are commonly methylated in association with high BMI. Epigenome-wide methylation profiles were determined using the Illumina HumanMethylation450 BeadChip array in the non-diseased breast tissue of 81 women undergoing breast surgery between 2009 and 2013 at the University of North Carolina Hospitals. Multivariable, robust linear regression was performed to identify methylation sites associated with BMI at a false discovery rate q value <0.05. Gene expression microarray data was used to identify which of the BMI-associated methylation sites also showed correlation with gene expression. Gene set enrichment analysis was conducted to assess which pathways were enriched among the BMI-associated methylation sites. Of the 431,568 methylation sites analyzed, 2573 were associated with BMI (q value <0.05), 57 % of which showed an inverse correlation with BMI. Pathways enriched among the 2573 probe sites included those involved in inflammation, insulin receptor signaling, and leptin signaling. We were able to map 1251 of the BMI-associated methylation sites to gene expression data, and, of these, 226 (18 %) showed substantial correlations with gene expression. Our results suggest that BMI is associated with genome-wide methylation in non-diseased breast tissue and may influence epigenetic pathways involved in inflammatory and other carcinogenic processes.
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Affiliation(s)
- Brionna Y Hair
- Department of Epidemiology, University of North Carolina at Chapel Hill, CB #7435, 2101 McGavran-Greenberg Hall, Chapel Hill, NC, 27599-7435, USA,
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Wu JP, Hsieh DJY, Kuo WW, Han CK, Pai P, Yeh YL, Lin CC, Padma VV, Day CH, Huang CY. Secondhand Smoke Exposure Reduced the Compensatory Effects of IGF-I Growth Signaling in the Aging Rat Hearts. Int J Med Sci 2015; 12:708-18. [PMID: 26392808 PMCID: PMC4571548 DOI: 10.7150/ijms.12032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 06/09/2015] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Secondhand smoke (SHS) exposure is associated with increased risk of cardiovascular disease. Aging is a physiological process that involves progressive impairment of normal heart functions due to increased vulnerability to damage. This study examines secondhand smoke exposure in aging rats to determine the age-related death-survival balance. METHODS Rats were placed into a SHS exposure chamber and exposed to smog. Old age male Sprague-Dawley rats were exposed to 10 cigarettes for 30 min, day and night, continuing for one week. After 4 weeks the rats underwent morphological and functional studies. Left ventricular sections were stained with hematoxylin-eosin for histopathological examination. TUNEL detected apoptosis cells and protein expression related death and survival pathway were analyzed using western blot. RESULTS Death receptor-dependent apoptosis upregulation pathways and the mitochondria apoptosis proteins were apparent in young SHS exposure and old age rats. These biological markers were enhanced in aging SHS-exposed rats. The survival pathway was found to exhibit compensation only in young SHS-exposed rats, but not in the aging rats. Further decrease in the activity of this pathway was observed in aging SHS-exposed rats. TUNEL apoptotic positive cells were increased in young SHS-exposed rats, and in aging rats with or without SHS-exposure. CONCLUSIONS Aging reduces IGF-I compensated signaling with accelerated cardiac apoptotic effects from second-hand smoke.
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Affiliation(s)
- Jia-Ping Wu
- 1. Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan
| | - Dennis Jine-Yuan Hsieh
- 2. School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan
| | - Wei-Wen Kuo
- 3. Department of Biological Science and Technology, China Medical University, Taichung
| | - Chien-Kuo Han
- 4. Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Peiying Pai
- 5. Division of Cardiology, China Medical University Hospital, Taichung, Taiwan
| | - Yu-Lan Yeh
- 6. Department of pathology, Changhua Christian Hospital, Changhua ; 7. Department of Medical Technology, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, Taiwan
| | - Chien-Chung Lin
- 8. Orthopaedic Department, Armed Forces General Hospital, Taichung, Taiwan
| | - V Vijaya Padma
- 9. Department of Biotechnology, Bharathiar University, Coimbatore-641 046, India
| | - Cecilia Hsuan Day
- 10. Department of Nursing, Mei Ho University, 23 Pingguang Road, Pingtung 91202, Taiwan
| | - Chih-Yang Huang
- 1. Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan ; 11. School of Chinese Medicine, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan ; 12. Department of Health and Nutrition Biotechnology, Asia University, 500 Lioufeng Road, Taichung 41354, Taiwan
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Wang S, Teng X, Wang Y, Yu HQ, Luo X, Xu A, Wu L. Molecular control of arsenite-induced apoptosis in Caenorhabditis elegans: roles of insulin-like growth factor-1 signaling pathway. CHEMOSPHERE 2014; 112:248-255. [PMID: 25048913 DOI: 10.1016/j.chemosphere.2014.04.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 04/02/2014] [Accepted: 04/05/2014] [Indexed: 06/03/2023]
Abstract
Apoptosis is one of the main cellular processes in responses to arsenic, the well known environmental carcinogen. By using the nematode Caenorhabditis elegans as an in vivo model, we found that insulin-like growth factor-1 networks and their target protein DAF-16/FOXO, known as key regulators of energy metabolism and growth, played important roles in arsenite-induced apoptosis. Inactivation of DAF-2, AGE-1 and AKT-1 caused worms more susceptible to arsenite-induced apoptosis, which could be attenuated by DAF-16 knockout. Worms with inactivated AKT-2 and SGK-1 or with constitutively activated PDK-1 and AKT-1 showed low levels of apoptosis, which could be elevated by DAF-16 mutation. Our results demonstrated that DAF-2/IGF-1R, AGE-1/PI3K, PDK-1/PDK1 and AKT-1/PKB negatively regulated the arsenite-induced apoptosis, whereas AKT-2 and SGK-1 acted proapoptotically. DAF-16/FOXO antagonized IGF-1 signals in signaling the arsenite-induced apoptosis, and apoptosis promoted by DAF-16 inactivation was attributed to its higher sensitivity to oxidative stress.
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Affiliation(s)
- Shunchang Wang
- Department of Life Science, Huainan Normal University, Huainan 232001, China.
| | - Xiaoxue Teng
- Department of Life Science, Huainan Normal University, Huainan 232001, China; School of Life Sciences, Anhui University, Hefei 230601, China
| | - Yun Wang
- Department of Life Science, Huainan Normal University, Huainan 232001, China
| | - Han-Qing Yu
- Department of Chemistry, University of Science & Technology of China, Hefei 230026, China
| | - Xun Luo
- Department of Life Science, Huainan Normal University, Huainan 232001, China; Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - An Xu
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Lijun Wu
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
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Choukair D, Hügel U, Sander A, Uhlmann L, Tönshoff B. Inhibition of IGF-I-related intracellular signaling pathways by proinflammatory cytokines in growth plate chondrocytes. Pediatr Res 2014; 76:245-51. [PMID: 24941214 DOI: 10.1038/pr.2014.84] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 02/27/2014] [Indexed: 01/31/2023]
Abstract
BACKGROUND Children with chronic inflammatory diseases suffer from severe growth failure associated with resistance toward the anabolic action of insulin-like growth factor I (IGF-I). We hypothesized that proinflammatory cytokines interfere with IGF-I signaling. METHODS We used the mesenchymal chondrogenic cell line RCJ3.1C5.18 as a model of the growth plate. Cell proliferation was assessed by [(3)H]-thymidine-uptake and differentiation by gene expression (quantitative reverse-transcriptase PCR) of specific differentiation markers. Key signaling molecules of the respective IGF-I-related intracellular pathways were determined by western immunoblotting. RESULTS Coincubation of the proinflammatory cytokines interleukin (IL)-1β (10 ng/ml), IL-6 (100 ng/ml), or tumor necrosis factor-α (50 ng/ml) with IGF-I inhibited IGF-I-driven cell proliferation by 50%, while baseline cell proliferation was not altered. These cytokines attenuated the IGF-I-induced phosphorylation of AKT as a key signaling molecule of the phosphatidylinositol-3 kinase pathway by 30-50% and the phosphorylation of ERK as a key signaling molecule of the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway by 50-75%. Also, IGF-I-enhanced chondrocyte differentiation was inhibited by these proinflammatory cytokines. CONCLUSION The insensitivity toward the anabolic action of IGF-I in the growth plate in conditions of chronic inflammation is partially due to inhibition of IGF-I-specific signaling pathways by proinflammatory cytokines, which affect both IGF-I-driven chondrocyte proliferation and differentiation.
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Affiliation(s)
- Daniela Choukair
- Department of Pediatrics I, University Children's Hospital Heidelberg, Heidelberg, Germany
| | - Ulrike Hügel
- Department of Pediatrics I, University Children's Hospital Heidelberg, Heidelberg, Germany
| | - Anja Sander
- Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | - Lorenz Uhlmann
- Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, Heidelberg, Germany
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Park SJ, Ryu J, Kim IH, Choi YH, Nam TJ. Induction of apoptosis by a peptide from Porphyra yezoensis: regulation of the insulin-like growth factor I receptor signaling pathway in MCF-7 cells. Int J Oncol 2014; 45:1011-6. [PMID: 24970277 PMCID: PMC4121416 DOI: 10.3892/ijo.2014.2509] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 05/16/2014] [Indexed: 11/24/2022] Open
Abstract
This study examined how PPY, a peptide from Porphyra yezoensis, regulates multiple cell growth-related signaling pathways in MCF-7 cells. This study determined that PPY induces cell cycle arrest and inhibits the IGF-IR signaling pathway. Cell proliferation studies revealed that PPY induced cell death in a dose-dependent manner. Expression levels of IGF-IR were decreased in MCF-7 cells by PPY in a dose-dependent manner. These results indicate that inhibition of the IGF-IR pathway is also involved in PPY induced proliferation of MCF-7 cells. In addition, these data demonstrated that PPY induces cell cycle arrest and activates apoptosis.
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Affiliation(s)
- Su-Jin Park
- Department of Food and Science, Pukyong National University, Busan 608-737, Republic of Korea
| | - Jina Ryu
- Department of Food and Science, Pukyong National University, Busan 608-737, Republic of Korea
| | - In-Hye Kim
- Institute of Fisheries Science, Pukyong National University, Busan 619-911, Republic of Korea
| | - Youn-Hee Choi
- Institute of Fisheries Science, Pukyong National University, Busan 619-911, Republic of Korea
| | - Taek-Jeong Nam
- Department of Food and Science, Pukyong National University, Busan 608-737, Republic of Korea
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Pourrajab F, Babaei Zarch M, Baghi Yazdi M, Rahimi Zarchi A, Vakili Zarch A. Application of stem cell/growth factor system, as a multimodal therapy approach in regenerative medicine to improve cell therapy yields. Int J Cardiol 2014; 173:12-9. [PMID: 24612559 DOI: 10.1016/j.ijcard.2014.02.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 12/26/2013] [Accepted: 02/08/2014] [Indexed: 12/13/2022]
Abstract
Stem cells hold a great promise for regenerative medicine, especially for replacing cells in infarcted organ that hardly have any intrinsic renewal capacity, including heart and brain. Signaling pathways that regulate pluripotency or lineage-specific gene and protein expression have been the major focus of stem cell research. Between them, there are some well known signaling pathways such as GF/GFR systems, SDF-1α/CXC4 ligand receptor interaction and PI3K/Akt signaling, and cytokines may regulate cell fate decisions, and can be utilized to positively influence cell therapy outcomes or accentuate synergistic compliance. For example, contributing factors in the progression of heart failure are both the loss of cardiomyocytes after myocardial infarction, and the absence of an adequate endogenous repair signaling. Combining cell engraftment with therapeutic signaling factor delivery is more exciting in terms of host progenitor/donor stem cell survival and proliferation. Thus stem cell-based therapy, besides triggering signaling pathways through GF/GFR systems can become a realistic option in regenerative processes for replacing lost cells and reconstituting the damaged organ, as before.
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Affiliation(s)
- Fatemeh Pourrajab
- School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran; Department of Clinical Biochemistry and Molecular Biology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
| | | | | | - Abolfazl Rahimi Zarchi
- School of Nursing, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Abbas Vakili Zarch
- School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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Fortuño MA, López N, González A, Díez J. Involvement of cardiomyocyte survival–apoptosis balance in hypertensive cardiac remodeling. Expert Rev Cardiovasc Ther 2014; 1:293-307. [PMID: 15030288 DOI: 10.1586/14779072.1.2.293] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The balance between cell death and cell survival is a tightly controlled process, especially in terminally differentiated cells, such as the cardiomyocyte. Accumulating data support a role for cardiomyocyte apoptosis in the development of several cardiac diseases, including the transition from hypertensive compensatory hypertrophy to heart failure. This review briefly summarizes the status of the knowledge regarding the death-survival balance of cardiomyocytes in the context of hypertensive heart disease. Several molecular and cellular aspects as well as the most relevant pathophysiological implications are presented. Moreover, diagnosis tools under development and the possibilities for pharmacological intervention are also examined.
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Affiliation(s)
- María A Fortuño
- Division of Cardiovascular Pathophysiology, School of Medicine, University of Navarra, Pamplona, Spain.
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Zhao H, Luo X, Zhou Z, Liu J, Tralau-Stewart C, George AJ, Ma D. Early treatment with xenon protects against the cold ischemia associated with chronic allograft nephropathy in rats. Kidney Int 2014; 85:112-23. [DOI: 10.1038/ki.2013.334] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 06/01/2013] [Accepted: 06/20/2013] [Indexed: 11/09/2022]
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Oliveira JM, Rebuffat SA, Gasa R, Burks DJ, Garcia A, Kalko SG, Zafra D, Guinovart JJ, Gomis R. Tungstate promotes β-cell survival in Irs2-/- mice. Am J Physiol Endocrinol Metab 2014; 306:E36-47. [PMID: 24253047 DOI: 10.1152/ajpendo.00409.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Pancreatic β-cells play a central role in type 2 diabetes (T2D) development, which is characterized by the progressive decline of the functional β-cell mass that is associated mainly with increased β-cell apoptosis. Thus, understanding how to enhance survival of β-cells is key for the management of T2D. The insulin receptor substrate-2 (IRS-2) protein is pivotal in mediating the insulin/IGF signaling pathway in β-cells. In fact, IRS-2 is critically required for β-cell compensation in conditions of increased insulin demand and for β-cell survival. Tungstate is a powerful antidiabetic agent that has been shown to promote β-cell recovery in toxin-induced diabetic rodent models. In this study, we investigated whether tungstate could prevent the onset of diabetes in a scenario of dysregulated insulin/IGF signaling and massive β-cell death. To this end, we treated mice deficient in IRS2 (Irs2(-/-)), which exhibit severe β-cell loss, with tungstate for 3 wk. Tungstate normalized glucose tolerance in Irs2(-/-) mice in correlation with increased β-cell mass, increased β-cell replication, and a striking threefold reduction in β-cell apoptosis. Islets from treated Irs2(-/-) exhibited increased phosphorylated Erk1/2. Interestingly, tungstate repressed apoptosis-related genes in Irs2(-/-) islets in vitro, and ERK1/2 blockade abolished some of these effects. Gene expression profiling showed evidence of a broad impact of tungstate on cell death pathways in islets from Irs2(-/-) mice, consistent with reduced apoptotic rates. Our results support the finding that β-cell death can be arrested in the absence of IRS2 and that therapies aimed at reversing β-cell mass decline are potential strategies to prevent the progression to T2D.
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Affiliation(s)
- Joana Moitinho Oliveira
- Diabetes and Obesity Research Laboratory, Institut d'Investigations Biomediques August Pi i Sunyer, Barcelona, Spain
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Nordstrand A, Lundholm M, Larsson A, Lerner UH, Widmark A, Wikström P. Inhibition of the insulin-like growth factor-1 receptor enhances effects of simvastatin on prostate cancer cells in co-culture with bone. CANCER MICROENVIRONMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL CANCER MICROENVIRONMENT SOCIETY 2013; 6:231-40. [PMID: 23335094 PMCID: PMC3855371 DOI: 10.1007/s12307-013-0129-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 01/08/2013] [Indexed: 01/26/2023]
Abstract
Prostate cancer (PC) bone metastases show weak responses to conventional therapies. Bone matrix is rich in growth factors, with insulin-like growth factor-1 (IGF-1) being one of the most abundant. IGF-1 acts as a survival factor for tumor cells and we speculate that bone-derived IGF-1 counteracts effects of therapies aimed to target bone metastases and, consequently, that therapeutic effects could be enhanced if given in combination with IGF-1 receptor (IGF-1R) inhibitors. Simvastatin inhibits the mevalonate pathway and has been found to induce apoptosis of PC cells. The aims of this study were to confirm stimulating effects of bone-derived IGF-1 on PC cells and to test if IGF-1R inhibition enhances growth inhibitory effects of simvastatin on PC cells in a bone microenvironment. The PC-3 and 22Rv1 tumor cell lines showed significantly induced cell growth when co-cultured with neonatal mouse calvarial bones. The tumor cell IGF-1R was activated by calvariae-conditioned media and neutralization of bone-derived IGF-1 abolished the calvarium-induced PC-3 cell growth. Treatment of PC-3 and 22Rv1 cells with simvastatin, or the IGF-1R inhibitor NVP-AEW541, reduced tumor cell numbers and viability, and induced apoptosis. Combined simvastatin and NVP-AEW541 treatment resulted in enhanced growth inhibitory effects compared to either drug given alone. Effects of simvastatin involved down-regulation of IGF-1R in PC-3 and of constitutively active androgen receptor variants in 22Rv1 cells. In conclusion, we suggest that IGF-1 inhibition may be a way to strengthen effects of apoptosis-inducing therapies on PC bone metastases; a possibility that needs to be further tested in pre-clinical models.
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Affiliation(s)
- Annika Nordstrand
- Department of Radiation Sciences, Oncology, Umeå University, 901 85 Umeå, Sweden
| | - Marie Lundholm
- Department of Medical Biosciences, Pathology, Umeå University, 901 85 Umeå, Sweden
| | | | - Ulf H. Lerner
- Department of Molecular Periodontology, Umeå University, Umeå, Sweden
- Centre for Bone and Arthritis Research at Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Anders Widmark
- Department of Radiation Sciences, Oncology, Umeå University, 901 85 Umeå, Sweden
| | - Pernilla Wikström
- Department of Medical Biosciences, Pathology, Umeå University, 901 85 Umeå, Sweden
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Abstract
Cytokines and growth factors play an integral role in the maintenance of immune homeostasis, the generation of protective immunity, and lung reparative processes. However, the dysregulated expression of cytokines and growth factors in response to infectious or noxious insults can initiate and perpetuate deleterious lung inflammation and fibroproliferation. In this article, we will comprehensively review the contribution of individual cytokines and growth factors and cytokine networks to key pathophysiological events in human and experimental acute lung injury (ALI), including inflammatory cell recruitment and activation, alveolar epithelial injury and repair, angiogenesis, and matrix deposition and remodeling. The application of cytokines/growth factors as prognostic indicators and therapeutic targets in human ALI is explored.
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Affiliation(s)
- Jane C Deng
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, UCLA Medical Center, Los Angeles, CA, USA
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Lee HE, Choi ES, Shin JA, Lee SO, Park KS, Cho NP, Cho SD. Fucoidan induces caspase-dependent apoptosis in MC3 human mucoepidermoid carcinoma cells. Exp Ther Med 2013; 7:228-232. [PMID: 24348795 PMCID: PMC3861359 DOI: 10.3892/etm.2013.1368] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 10/21/2013] [Indexed: 01/05/2023] Open
Abstract
Fucoidan is a sulfated polysaccharide present in brown algae that has been identified to exhibit multiple biological effects. In this study, the apoptotic effects of fucoidan in MC3 human mucoepidermoid carcinoma (MEC) cells were investigated. The apoptotic effects of fucoidan on MC3 MEC cells were evaluated by cell proliferation assay, 4′,6-diamidino-2-phenylindole staining and western blot analysis. The results showed that fucoidan decreased cell proliferation and induced caspase-dependent apoptosis in MC3 MEC cells. Fucoidan downregulated the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, whereas phospho-p38 mitogen-activated protein kinase or phospho-c-Jun NH2-terminal kinase (JNK) levels were not altered. In addition, fucoidan significantly decreased the expression levels of myeloid cell leukemia-1 (Mcl-1). These results suggest that fucoidan is able to modulate the ERK1/2 pathway and thereby regulate Mcl-1 protein expression and induce apoptosis in MC3 MEC cells. Therefore, fucoidan may be a promising agent for the treatment of human MEC.
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Affiliation(s)
- Hang-Eun Lee
- Department of Oral Pathology, School of Dentistry, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea
| | - Eun-Sun Choi
- Department of Oral Pathology, School of Dentistry, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea
| | - Ji-Ae Shin
- Department of Oral Pathology, School of Dentistry, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea
| | - Syng-Ook Lee
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX 77843-4466, USA
| | - Ki-Soo Park
- Department of Translational Research, Korea Health Industry Development Institute (KHIDI), Cheongwon-gun 363-951, Republic of Korea
| | - Nam-Pyo Cho
- Department of Oral Pathology, School of Dentistry, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea
| | - Sung-Dae Cho
- Department of Oral Pathology, School of Dentistry, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea
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Jin E, Kim JM, Kim SW. Priming of mononuclear cells with a combination of growth factors enhances wound healing via high angiogenic and engraftment capabilities. J Cell Mol Med 2013; 17:1644-51. [PMID: 24118840 PMCID: PMC3914645 DOI: 10.1111/jcmm.12152] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Accepted: 09/04/2013] [Indexed: 12/26/2022] Open
Abstract
Recently, we demonstrated that a specific combination of growth factors enhances the survival, adhesion and angiogenic potential of mononuclear cells (MNCs). In this study, we sought to investigate the changes of the angiogenic potential of MNCs after short-time priming with a specific combination of growth factors. MNCs were isolated using density gradient centrifugation and incubated with a priming cocktail containing epidermal growth factor (EGF), insulin-like growth factor (IGF)-1, fibroblast growth factor (FGF)-2, FMS-like tyrosine kinase (Flt)-3L, Angiopoietin (Ang)-1, granulocyte chemotactic protein (GCP)-2 and thrombopoietin (TPO) (all 400 ng/ml) for 15, 30 and 60 min. Wounds in nonobese diabetic-severe combined immune deficiency (NOD-SCID) mice were created by skin excision followed by cell transplantation. We performed a qRT-PCR analysis on the growth factor–primed cells. The angiogenic factors vascular endothelial growth factor (VEGF)-A, FGF-2, hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF) and interleukin (IL)-8 and the anti-apoptotic factors IGF-1 and transforming growth factor-β1 were significantly elevated in the MNCs primed for 30 min. (T30) compared with the non-primed MNCs (T0). The scratch wound assay revealed that T30- conditioned media (CM) significantly increased the rate of fibroblast-mediated wound closure compared with the rates from T0-CM and human umbilical vein endothelial cells (HUVEC)-CM at 20 hrs. In vivo wound healing results revealed that the T30-treated wounds demonstrated accelerated wound healing at days 7 and 14 compared with those treated with T0. The histological analyses demonstrated that the number of engrafted cells and transdifferentiated keratinocytes in the wounds were significantly higher in the T30-transplanted group than in the T0-transplanted group. In conclusion, this study suggests that short-term priming of MNCs with growth factors might be alternative therapeutic option for cell-based therapies.
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Affiliation(s)
- Enze Jin
- Department of Cardiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
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66
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Thakur S, Garg N, Adamo ML. Deficiency of insulin-like growth factor-1 receptor confers resistance to oxidative stress in C2C12 myoblasts. PLoS One 2013; 8:e63838. [PMID: 23675509 PMCID: PMC3651254 DOI: 10.1371/journal.pone.0063838] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 04/11/2013] [Indexed: 11/18/2022] Open
Abstract
IGF-1 receptor (IGF-1R) signaling regulates cell growth, transformation and survival. Haploinsufficiency of the IGF-1R is reported to paradoxically confer resistance to oxidative stress in vivo and in cells cultured from Igf1r+/− mice. In order to determine whether IGF-1R deficiency directly confers resistance to oxidative stress in specific cell types, an siRNA-mediated approach was applied to reduce IGF-1R in C2C12 myoblasts, NIH3T3 fibroblasts and MC3T3-E1 osteoblasts. Treating the IGF-1R deficient myoblasts with H2O2 resulted in significantly higher phosphorylation of Akt as compared to cells having normal expression of IGF-1R. Similar results were obtained with UV treatment, another inducer of oxidative stress. This enhanced activation of Akt was associated with reduced level of cleaved caspase-3 and PARP. Moreover, in the IGF-1R knockdown myoblasts, phosphorylation of the Akt substrate Bad was enhanced after peroxide treatment. However, in NIH-3T3 fibroblasts and MC3T3-E1 osteoblasts, the loss of IGF-1R by siRNA directed knockdown was associated with reduced levels of phosphorylated Akt on treatment with H2O2 or UV as compared to control cells and these cells showed more apoptosis. These results suggest a novel mechanism of cell type specific differential regulation of resistance to oxidative stress induced apoptosis by reduced levels of IGF-1R.
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Affiliation(s)
- Sachin Thakur
- Department of Biochemistry, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Neha Garg
- Department of Biochemistry, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Martin L. Adamo
- Department of Biochemistry, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- The Sam and Ann Barshop Institute for Longevity and Aging Studies at The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- * E-mail:
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Loh AHP, Brennan RC, Lang WH, Hickey RJ, Malkas LH, Sandoval JA. Dissecting the PI3K Signaling Axis in Pediatric Solid Tumors: Novel Targets for Clinical Integration. Front Oncol 2013; 3:93. [PMID: 23638435 PMCID: PMC3636761 DOI: 10.3389/fonc.2013.00093] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 04/05/2013] [Indexed: 12/19/2022] Open
Abstract
Children with solid tumors represent a unique population. Recent improvements in pediatric solid tumor survival rates have been confined to low- and moderate-risk cancers, whereas minimal to no notable improvement in survival have been observed in high-risk and advanced-stage childhood tumors. Treatments for patients with advanced disease are rarely curative, and responses to therapy are often followed by relapse, which highlights the large unmet need for novel therapies. Recent advances in cancer treatment have focused on personalized therapy, whereby patients are treated with agents that best target the molecular drivers of their disease. Thus, a better understanding of the pathways that drive cancer or drug resistance is of critical importance. One such example is the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway, which is activated in many solid cancer patients and represents a target for therapy. PI3K/Akt/mTOR pathway activation has also been observed in tumors resistant to agents targeting upstream receptor tyrosine kinases (RTKs). Agents that target this pathway have the potential to shut down survival pathways, and are being explored both in the setting of pathway-activating mutations and for their ability to restore sensitivity to upstream signaling targeted agents. Here, we examine the role of the PI3K/Akt/mTOR pathway in pediatric solid tumors, review the novel agents being explored to target this pathway, and explore the potential role of the inhibition of this pathway in the clinical development of these agents in children.
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Affiliation(s)
- Amos H P Loh
- Department of Surgery, St. Jude Children's Research Hospital Memphis, TN, USA
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Tsuchiya N, Narita S, Inoue T, Saito M, Numakura K, Huang M, Hatakeyama S, Satoh S, Saito S, Ohyama C, Arai Y, Ogawa O, Habuchi T. Insulin-like growth factor-1 genotypes and haplotypes influence the survival of prostate cancer patients with bone metastasis at initial diagnosis. BMC Cancer 2013; 13:150. [PMID: 23530598 PMCID: PMC3622563 DOI: 10.1186/1471-2407-13-150] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 03/18/2013] [Indexed: 12/01/2022] Open
Abstract
Background The insulin-like growth factor-1 (IGF-1) plays an important role in growth of prostate cancer (PCa) cells and facilitating the development and progression of PCa. This study aimed to evaluate the association of polymorphisms in three linkage disequilibrium (LD) blocks of the IGF-1 on the survival of metastatic PCa patients. Methods A total of 215 patients with bone metastases at initial presentation were included in this study. The cytosine-adenine (CA) repeat polymorphism and rs12423791 were selected as representative polymorphisms in the LD blocks 1 and 2, respectively. Haplotype in the LD block 3 was analyzed using two tag single nucleotide polymorphisms (SNPs), rs6220 and rs7136446. Cancer-specific survival rate was estimated from the Kaplan-Meier curve, and the survival data were compared using the log-rank test. Results Cancer-specific survival was significantly associated with the CA repeat polymorphism, rs12423791, and rs6220 (P = 0.013, 0.014, and 0.014, respectively). Although rs7136446 had no significant association with survival, the haplotype in the LD block 3 was significantly associated with cancer-specific survival (P = 0.0003). When the sum of the risk genetic factors in each LD block (19-repeat allele, C allele of rs12423791, or C-T haplotype) was considered, patients with all the risk factors had significantly shorter cancer specific-survival than those with 0–2 risk factors (P = 0.0003). Conclusions Polymorphisms in the IGF-1, especially a haplotype in the LD block 3, are assumed to be genetic markers predicting the outcome of metastatic PCa.
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Affiliation(s)
- Norihiko Tsuchiya
- Department of Urology, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan
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Fineschi S, De Cunto G, Facchinetti F, Civelli M, Imbimbo BP, Carnini C, Villetti G, Lunghi B, Stochino S, Gibbons DL, Hayday A, Lungarella G, Cavarra E. Receptor for advanced glycation end products contributes to postnatal pulmonary development and adult lung maintenance program in mice. Am J Respir Cell Mol Biol 2013; 48:164-71. [PMID: 23144333 DOI: 10.1165/rcmb.2012-0111oc] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The role of the receptor for advanced glycation end products (RAGE) in promoting the inflammatory response through activation of NF-κB pathway is well established. Recent findings indicate that RAGE may also have a regulative function in apoptosis, as well as in cellular proliferation, differentiation, and adhesion. Unlike other organs, lung tissue in adulthood and during organ development shows relatively high levels of RAGE expression. Thus a role for the receptor in lung organogenesis and homeostasis may be proposed. To evaluate the role of RAGE in lung development and adult lung homeostasis, we generated hemizygous and homozygous transgenic mice overexpressing human RAGE, and analyzed their lungs from the fourth postnatal day to adulthood. Moderate RAGE hyperexpression during lung development influenced secondary septation, resulting in an impairment of alveolar morphogenesis and leading to significant changes in morphometric parameters such as airspace number and the size of alveolar ducts. An increase in alveolar cell apoptosis and a decrease in cell proliferation were demonstrated by the terminal deoxy-nucleotidyltransferase-mediated dUTP nick end labeling reaction, active caspase-3, and Ki-67 immunohistochemistry. Alterations in elastin organization and deposition and in TGF-β expression were observed. In homozygous mice, the hyperexpression of RAGE resulted in histological changes resembling those changes characterizing human bronchopulmonary dysplasia (BPD). RAGE hyperexpression in the adult lung is associated with an increase of the alveolar destructive index and persistent inflammatory status leading to "destructive" emphysema. These results suggest an important role for RAGE in both alveolar development and lung homeostasis, and open new doors to working hypotheses on the pathogenesis of BPD and chronic obstructive pulmonary disease.
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Affiliation(s)
- Silvia Fineschi
- Department of Physiopathology, University of Siena, Via Aldo Moro 6, I-53100 Siena, Italy
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71
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D'Onofrio PM, Koeberle PD. What can we learn about stroke from retinal ischemia models? Acta Pharmacol Sin 2013. [PMID: 23202803 DOI: 10.1038/aps.2012.165] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Retinal ischemia is a very useful model to study the impact of various cell death pathways, such as apoptosis and necrosis, in the ischemic retina. However, it is important to note that the retina is formed as an outpouching of the diencephalon and is part of the central nervous system. As such, the cell death pathways initiated in response to ischemic damage in the retina reflect those found in other areas of the central nervous system undergoing similar trauma. The retina is also more accessible than other areas of the central nervous system, thus making it a simpler model to work with and study. By utilizing the retinal model, we can greatly increase our knowledge of the cell death processes initiated by ischemia which lead to degeneration in the central nervous system. This paper examines work that has been done so far to characterize various aspects of cell death in the retinal ischemia model, such as various pathways which are activated, and the role neurotrophic factors, and discusses how these are relevant to the treatment of ischemic damage in both the retina and the greater central nervous system.
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Insulin-like growth factor 1 mediates negative feedback to somatotroph GH expression via POU1F1/CREB binding protein interactions. Mol Cell Biol 2012; 32:4258-69. [PMID: 22890843 DOI: 10.1128/mcb.00171-12] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Circulating insulin-like growth factor 1 (IGF-1) has been shown to act as a negative feedback regulator of growth hormone (GH) gene expression; however, the mechanism of this negative feedback is poorly understood. Activation and regulation of GH gene expression require the binding of the transcription factor POU1F1 to the GH promoter along with cyclic AMP (cAMP) response element binding protein (CREB) binding protein (CBP). We investigate the role of CBP as a target of IGF-1 somatotroph regulation using the MtT/S somatotroph cell line. IGF-1 significantly inhibits basal GH mRNA levels but not POU1F1 levels. Chromatin immunoprecipitation assays demonstrate inhibition of CBP binding to the GH promoter after IGF-1 treatment. We hypothesized that IGF-1 receptor (IGF-1R) signaling disrupts the POU1F1/CBP complex to inhibit gene expression. In support, the use of a mutant CBP (S436A) construct, which lacks a critical phosphorylation site, leads to the loss of IGF-1 inhibition. The studies of CBP (S436A) knock-in mice show elevated serum GH levels, a greater response to GH releasing hormone (GHRH) stimulation along with lower weight gain, and decreased body fat. Our data confirm the inhibitory effects of IGF-1 on GH expression at the level of the promoter and provide evidence of CBP's role as a target of IGF-1R signaling.
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Kim Y, Li E, Park S. Insulin-like growth factor-1 inhibits 6-hydroxydopamine-mediated endoplasmic reticulum stress-induced apoptosis via regulation of heme oxygenase-1 and Nrf2 expression in PC12 cells. Int J Neurosci 2012; 122:641-9. [PMID: 22703470 DOI: 10.3109/00207454.2012.702821] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Endoplasmic reticulum (ER) stress and oxidative stress appear to play a critical role in the progression of Parkinson's disease (PD). Insulin-like growth factor (IGF)-1, a 70-amino acid polypeptide trophic factor, acts as a potent neurotrophic, neurogenic, and neuroprotective/anti-apoptotic factor. In this study, we investigated the protective mechanisms of IGF-1 in rat pheochromocytoma PC12 cells exposed to the PD-related neurotoxin 6-hydroxydopamine (6-OHDA). The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) coordinates expression of genes required for free radical scavenging, detoxification of xenobiotics, and maintenance of redox potential. Exposure of cells to 6-OHDA resulted in an increase in ER-stress-induced apoptotic cell death, which was significantly reduced by treatment of cells with IGF-1. IGF-1 treatment significantly increased BiP and C/EBP homologous protein expression in 6-OHDA-treated cultures. IGF-1 protected cells from 6-OHDA-induced insult by inhibiting intracellular reactive oxygen species generation. Compared with vehicle-treated controls, the expression of Nrf2 and heme oxygenase-1 (HO-1) was increased in 6-OHDA-treated cells. IGF-1 significantly up-regulated HO-1 in cells exposed to 6-OHDA. These results suggest that IGF-1 augment cellular anti-oxidant defense mechanism, at least in part, through the up-regulation of HO-1 expression.
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Affiliation(s)
- Yumi Kim
- Department of Pharmacology and Biomedical Science Institute, School of Medicine, Kyung Hee University, Seoul, Korea
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Chomwisarutkun K, Murani E, Brunner R, Ponsuksili S, Wimmers K. QTL region-specific microarrays reveal differential expression of positional candidate genes of signaling pathways associated with the liability for the inverted teat defect. Anim Genet 2012; 44:139-48. [PMID: 22690698 DOI: 10.1111/j.1365-2052.2012.02378.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2012] [Indexed: 01/23/2023]
Abstract
The inverted teat defect is the most common disorder of the mammary complex in pigs. It is characterized by the failure of teats to protrude from the udder surface, preventing normal milk flow and thus limiting the rearing capacity and increasing the risk of mastitis. The inverted teat defect is a liability trait with a complex mode of inheritance. We previously identified QTL for inverted teats. As a complementary approach that integrates map-based efforts to identify candidate genes for the inverted teat defect with function-driven expression analysis, application-specific microarrays were constructed that cover 1525 transcripts mapping in QTL regions on pig chromosomes 2, 3, 4, 6 and 11. About 950 transcripts were expressed in epithelial and mesenchymal teat tissue. The expression of three categories of teats was compared: normal teats of both non-affected and affected animals and inverted teats of affected animals. In epithelium and mesenchyme, 62 and 24 genes respectively were significantly differentially expressed (DE). The majority of biofunctions to which a significant number of DE genes were assigned are related to the following: (1) cell maintenance, proliferation, differentiation and replacement; (2) organismal, organ and tissue development; or (3) genetic information and nucleic acid processing. Moreover, the DE genes belong almost exclusively to canonical pathways related to signaling rather than metabolic pathways. This is in line with findings obtained by genome-wide catalogue microarrays. This study adds another piece to the puzzle of the etiology of inverted teats by indicating that causal genetic variation leading to the disorder is likely among the genes encoding for members of the signaling cascades of growth factors.
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Affiliation(s)
- K Chomwisarutkun
- Research Unit Molecular Biology, Leibniz Institute for Farm Animal Biology, Wilhelm-Stahl-Allee 2, Dummerstorf, Germany
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Kiepe D, Tönshoff B. Insulin-like growth factors in normal and diseased kidney. Endocrinol Metab Clin North Am 2012; 41:351-74, vii. [PMID: 22682635 DOI: 10.1016/j.ecl.2012.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
This article reviews the physiology of the insulin-like growth factor (IGF) system in the kidney and the changes and potential role of this system in selected renal diseases. The potential therapeutic uses of recombinant human IGF-I for the treatment of acute and chronic kidney failure are briefly discussed.
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Affiliation(s)
- Daniela Kiepe
- Department of Pediatrics I, University Children's Hospital Heidelberg, INF 430, D-69120 Heidelberg, Germany.
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Kuemmerle JF. Insulin-like growth factors in the gastrointestinal tract and liver. Endocrinol Metab Clin North Am 2012; 41:409-23, vii. [PMID: 22682638 PMCID: PMC3372868 DOI: 10.1016/j.ecl.2012.04.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The liver is a major source of insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) that are present in the circulation and have important endocrine activities relating to energy metabolism, body size, carcinogenesis, and various organ-specific functions. Although IGFs have only minor effects on the normal liver itself, production of IGFs and IGFBPs in a tissue-specific manner in the gastrointestinal tract exert important regulatory effects on cellular proliferation, survival, and apoptosis. IGFs and IGFBPs play important regulatory roles in the response of both the liver and the gastrointestinal tract to inflammation and in the development of neoplasia.
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Affiliation(s)
- John F Kuemmerle
- Department of Medicine, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA 23298-0341, USA.
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Vivar R, Humeres C, Varela M, Ayala P, Guzmán N, Olmedo I, Catalán M, Boza P, Muñoz C, Díaz Araya G. Cardiac fibroblast death by ischemia/reperfusion is partially inhibited by IGF-1 through both PI3K/Akt and MEK-ERK pathways. Exp Mol Pathol 2012; 93:1-7. [PMID: 22537549 DOI: 10.1016/j.yexmp.2012.01.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 12/21/2011] [Accepted: 01/31/2012] [Indexed: 11/18/2022]
Abstract
UNLABELLED Cardiac fibroblast (CF) death by ischemia/reperfusion (I/R) has major implications for cardiac wound healing. Although IGF-1 has well-known cytoprotective effects, no study has been done on CF subjected to simulated I/R. Simulated ischemia of neonate rat CF was performed in a free oxygen chamber in an ischemic medium; reperfusion was done in normal culture conditions. Cell viability was evaluated by trypan blue assay, and apoptosis by a FACS flow cytometer; p-ERK-1/2 and p-Akt levels were determined by western blot. We showed that simulated I/R triggers CF death by necrosis and apoptosis. IGF-1 partially inhibits I/R-induced apoptosis. PD98059 and LY294002 neutralize the preventive effects of IGF-1. CONCLUSION IGF-1 partially inhibits CF apoptosis induced by simulated I/R by PI3K/Akt- and MEK/ERK1/2-dependent signaling pathways.
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Affiliation(s)
- Raúl Vivar
- Laboratorio de Farmacoquímica y Centro FONDAP CEMC, Centro de Estudios Moleculares de Célula, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
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Fidler MJ, Shersher DD, Borgia JA, Bonomi P. Targeting the insulin-like growth factor receptor pathway in lung cancer: problems and pitfalls. Ther Adv Med Oncol 2012; 4:51-60. [PMID: 22423264 PMCID: PMC3296080 DOI: 10.1177/1758834011427576] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The insulin-like growth factor (IGF) pathway is a complex pathway involving interactions between membrane-bound receptors, ligands, binding proteins, downstream effectors, and other receptor tyrosine kinase signaling cascades. The IGF pathway has been identified as a potential therapeutic target in non-small cell lung cancer (NSCLC) based on the following provocative factors. Preclinical observations in NSCLC have shown that this pathway is involved in tumor cell proliferation, survival, and invasiveness. In addition, IGF-1R protein expression is found in a significant number of non-small cell tumor specimens. Initial therapeutic efforts involved the development of monoclonal antibodies and tyrosine kinase inhibitors that target IGF-1R, a transmembrane receptor tyrosine kinase. Enthusiasm for targeting this pathway increased when a randomized phase II study showed that combining an anti-IGF-1R monoclonal antibody (figitumumab) with a platinum doublet resulted in a higher response rate and trends for superior progression-free survival and overall survival. Subsequently, a phase III study failed to confirm the promising results observed in the phase II trial. Currently, investigators are studying different monoclonal antibodies and tyrosine kinases targeting IGF-1R. In unselected patients, results presented thus far do not suggest efficacy of this agent. However, retrospective subgroup analyses suggest that circulating IGF-1 levels might identify patients who could benefit from treatment with an IGF-1R monoclonal antibody and may warrant further exploratory studies for predictive molecular markers. The purpose of this paper is to briefly discuss the IGF pathway and its relationship with other signaling pathways in lung cancer and to review the ongoing IGF clinical trials and efforts to identify predictive molecular markers.
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Affiliation(s)
- Mary Jo Fidler
- Section of Medical Oncology, Rush University Medical Center, 1725 West Harrison Street, Suite 821, Chicago, IL 60612, USA
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Abstract
The protein kinase C (PKC) family of enzymes regulates cell physiology through phosphorylation of serine and threonine residues of many proteins in most cell types. Here we identify PKC-β1 and PKC-γ as isoforms that are essential for rod photoreceptor differentiation in mouse retinas. Using ex vivo retinal explants, we found that phorbol ester 12-myristate 13-acetate and insulin-like growth factor 1 (IGF1) induced rod differentiation, as defined by opsin or Crx expression, in a PKC-dependent manner days ahead of rod development in untreated explants. PKC-β1 and PKC-γ were colocalized with proliferating cell nuclear antigen (PCNA)- and STAT3-positive progenitors through the later differentiation period. Pharmacological or genetic inhibition of either isoform resulted in a partial reduction in the appearance of rods, whereas removing both isoforms resulted in their complete absence. Furthermore, a significant decline of STAT3 tyrosine phosphorylation was observed by activation of PKC, while inhibition of PKC resulted in an increase of phosphorylated STAT3 along with a delayed cell cycle exit of progenitors with prolonged PCNA expression. In adult retinas, IGF1 activates PI-3 kinase (PI3K), but in neonatal retinas its action is identical to the action of an PI3K inhibitor. These data unveil a novel signaling cascade that coordinates and regulates rod differentiation through specific PKC isoforms in mammals.
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Tran PV, Fretham SJB, Wobken J, Miller BS, Georgieff MK. Gestational-neonatal iron deficiency suppresses and iron treatment reactivates IGF signaling in developing rat hippocampus. Am J Physiol Endocrinol Metab 2012; 302:E316-24. [PMID: 22068601 PMCID: PMC3287363 DOI: 10.1152/ajpendo.00369.2011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Gestational-neonatal iron deficiency, a common micronutrient deficiency affecting the offspring of more than 30% of pregnancies worldwide, leads to long-term cognitive and behavioral abnormalities. Preclinical models of gestational-neonatal iron deficiency result in reduced energy metabolism and expression of genes critical for neuronal plasticity and cognitive function, which are associated with a smaller hippocampal volume and abnormal neuronal dendrite growth. Because insulin-like growth factor (IGF) modulates early postnatal cellular growth, differentiation, and survival, we used a dietary-induced rat model to assess the effects of gestational iron deficiency on activity of the IGF system. We hypothesized that gestational iron deficiency attenuates postnatal hippocampal IGF signaling and results in downstream effects that contribute to hippocampal anatomic and functional deficits. At postnatal day (P) 15 untreated gestational-neonatal iron deficiency markedly suppressed hippocampal IGF activation and protein kinase B signaling, and reduced neurogenesis, while elevating extracellular signal-regulated kinase 1/2 signaling and hypoxia-inducible factor-1α expression. Iron treatment beginning at P7 restored IGF signaling, increased neurogenesis, and normalized all parameters by the end of rapid hippocampal differentiation (P30). Expression of the neuron-specific synaptogenesis marker, disc-large homolog 4 (PSD95), increased more rapidly than the glia-specific myelination marker, myelin basic protein, following iron treatment, suggesting a more robust response to iron therapy in IGF-I-dependent neurons than IGF-II-dependent glia. Collectively, our findings suggest that IGF dysfunction is in part responsible for hippocampal abnormalities in untreated iron deficiency. Early postnatal iron treatment of gestational iron deficiency reactivates the IGF system and promotes neurogenesis and differentiation in the hippocampus during a critical developmental period.
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MESH Headings
- Anemia, Iron-Deficiency/diet therapy
- Anemia, Iron-Deficiency/metabolism
- Anemia, Iron-Deficiency/pathology
- Animals
- Female
- Gene Expression Regulation, Developmental
- Hippocampus/metabolism
- Hippocampus/pathology
- Insulin-Like Growth Factor Binding Protein 3/genetics
- Insulin-Like Growth Factor Binding Protein 3/metabolism
- Insulin-Like Growth Factor I/genetics
- Insulin-Like Growth Factor I/metabolism
- Insulin-Like Growth Factor II/genetics
- Insulin-Like Growth Factor II/metabolism
- Iron, Dietary/administration & dosage
- Iron, Dietary/therapeutic use
- Lactation
- Male
- Maternal Nutritional Physiological Phenomena
- Neurogenesis
- Neurons/metabolism
- Pregnancy
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Receptor, Insulin/genetics
- Receptor, Insulin/metabolism
- Signal Transduction
- Somatomedins/genetics
- Somatomedins/metabolism
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Affiliation(s)
- Phu V Tran
- Center for Neurobehavioral Development, University of Minnesota, Minneapolis MN, USA.
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81
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Woo JK, Choi Y, Oh SH, Jeong JH, Choi DH, Seo HS, Kim CW. Mucin 1 enhances the tumor angiogenic response by activation of the AKT signaling pathway. Oncogene 2011; 31:2187-98. [PMID: 21927028 DOI: 10.1038/onc.2011.410] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Although the hyper-glycosylated transmembrane protein Mucin 1 (MUC1) is aberrantly overexpressed in human breast carcinoma, the biological significance of MUC1 overexpression is unclear. This study showed that MUC1 expression promoted the synthesis and secretion of vascular endothelial growth factor (VEGF) through the AKT signaling pathway. Increase VEGF production through MUC1 expression had a number of effect. First, MUC1 transfection increased expression of VEGF in breast cancer cells. Second, MUC1-mediated VEGF induction was attenuated by a chemical inhibitor of AKT or MUC1 knock-down by MUC1 siRNA. Third, MUC1 expression led to the activation of insulin-like growth factor-1 receptor, which correlated with VEGF expression. In addition, when MDA-MB-231 human breast cancer cells were directly injected into NOD/SCID mice, MUC1 expression accelerated xenograft tumor growth in vivo. Finally, MUC1 expression enhanced tumor growth and angiogenesis in a PyMT-MMTV/hMUC1 transgenic mouse model. Concurrent with these results, analysis of a human tissue microarray identified a high correlation between MUC1 and VEGF expression in human breast carcinoma. The current report is the first to demonstrate that MUC1 expression promotes angiogenesis in human breast cancer in vivo and in vitro.
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Affiliation(s)
- J K Woo
- Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea
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82
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Mahajan UM, Gupta C, Wagh PR, Karpe PA, Tikoo K. Alteration in inflammatory/apoptotic pathway and histone modifications by nordihydroguaiaretic acid prevents acute pancreatitis in swiss albino mice. Apoptosis 2011; 16:1138-49. [DOI: 10.1007/s10495-011-0643-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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83
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Gafuik C, Steller H. A gain-of-function germline mutation in Drosophila ras1 affects apoptosis and cell fate during development. PLoS One 2011; 6:e23535. [PMID: 21858158 PMCID: PMC3155559 DOI: 10.1371/journal.pone.0023535] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 07/19/2011] [Indexed: 12/30/2022] Open
Abstract
The RAS/MAPK signal transduction pathway is an intracellular signaling cascade that transmits environmental signals from activated receptor tyrosine kinases (RTKs) on the cell surface and other endomembranes to transcription factors in the nucleus, thereby linking extracellular stimuli to changes in gene expression. Largely as a consequence of its role in oncogenesis, RAS signaling has been the subject of intense research efforts for many years. More recently, it has been shown that milder perturbations in Ras signaling during embryogenesis also contribute to the etiology of a group of human diseases. Here we report the identification and characterization of the first gain-of-function germline mutation in Drosophila ras1 (ras85D), the Drosophila homolog of human K-ras, N-ras and H-ras. A single amino acid substitution (R68Q) in the highly conserved switch II region of Ras causes a defective protein with reduced intrinsic GTPase activity, but with normal sensitivity to GAP stimulation. The ras1R68Q mutant is homozygous viable but causes various developmental defects associated with elevated Ras signaling, including cell fate changes and ectopic survival of cells in the nervous system. These biochemical and functional properties are reminiscent of germline Ras mutants found in patients afflicted with Noonan, Costello or cardio-facio-cutaneous syndromes. Finally, we used ras1R68Q to identify novel genes that interact with Ras and suppress cell death.
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Affiliation(s)
- Christopher Gafuik
- Howard Hughes Medical Institute, The Rockefeller University, New York, New York, United States of America
| | - Hermann Steller
- Howard Hughes Medical Institute, The Rockefeller University, New York, New York, United States of America
- * E-mail:
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84
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George S, Bennet L, Weaver-Mikaere L, Fraser M, Bouwmans J, Mathai S, Skinner S, Gunn A. White Matter Protection with Insulin-Like Growth Factor 1 and Hypothermia Is Not Additive after Severe Reversible Cerebral Ischemia in Term Fetal Sheep. Dev Neurosci 2011; 33:280-7. [DOI: 10.1159/000329923] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Accepted: 06/06/2011] [Indexed: 12/13/2022] Open
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85
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Kim MH, Zhang HZ, Kim SW. Combined growth factors enhanced angiogenic potential of cord blood-derived mononuclear cells transplanted to ischemic limbs. J Mol Cell Cardiol 2011; 51:702-12. [PMID: 21782826 DOI: 10.1016/j.yjmcc.2011.07.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 04/07/2011] [Accepted: 07/07/2011] [Indexed: 01/31/2023]
Abstract
Stem cell therapy has recently been limited by poor engraftment and the marginal influence of the administered cells. This study aimed to enhance the survival and angiogenic capacity of human umbilical cord blood (UCB)-derived mononuclear cells (MNCs) and to demonstrate their therapeutic effects on experimental ischemia. A specific culture medium containing five growth factors (Flt-3L, EGF, TPO, FGF and IGF-1) augmented cell proliferation, adhesion potential as well as stimulated MNCs to become progenitor-like cells. In addition, qRT-PCR demonstrated that MNCs cultured with these five growth factors (5f-MNCs) markedly up-regulated multiple angiogenic, arteriogenic and anti-apoptotic factors compared with uncultured MNCs. In an ischemic hindlimb model, the injection of 5f-MNCs prevented limb loss and augmented blood perfusion, capillary density, vascular maturation and angiogenic cytokines in the affected tissues. In addition, the 5f-MNCs exhibited an increased engraftment rate and an endothelial phenotype and stimulated angiogenic factors in ischemic hindlimbs as demonstrated by flow cytometric, immunohistochemical and qRT-PCR analyses. Taken together, these data suggest that 5f-MNCs could be used as a novel therapy for the treatment of ischemic cardiovascular disease due to their increased level of engraftment and angiogenic potential.
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Affiliation(s)
- Moo Hyun Kim
- Department of Cardiology, College of Medicine, Dong-A University, Regional Clinical Center, Dong-A University Hospital, Busan, South Korea
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86
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Simpson JE, Ince PG, Shaw PJ, Heath PR, Raman R, Garwood CJ, Gelsthorpe C, Baxter L, Forster G, Matthews FE, Brayne C, Wharton SB. Microarray analysis of the astrocyte transcriptome in the aging brain: relationship to Alzheimer's pathology and APOE genotype. Neurobiol Aging 2011; 32:1795-807. [PMID: 21705112 DOI: 10.1016/j.neurobiolaging.2011.04.013] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Revised: 03/21/2011] [Accepted: 04/20/2011] [Indexed: 12/31/2022]
Abstract
Astrocytes contribute to a variety of functions in the brain, including homeostasis, synapse formation, plasticity, and metabolism. Astrocyte dysfunction may disrupt their normal role, including neuronal support, thereby contributing to neurodegenerative pathologies, including Alzheimer's disease (AD). To understand the role of astrocytes in the pathogenesis of age-related disorders, we isolated astrocytes by laser capture microdissection, using glial fibrillary acidic protein (GFAP) as a marker, and characterized the astrocyte transcriptome at different Braak neurofibrillary tangle stages in postmortem temporal cortex samples derived from the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS) cohort, using microarray analysis. The largest number of significant, differentially expressed genes were identified when the expression profile of astrocytes from isocortical stages of neurofibrillary tangle pathology (Braak stages V-VI) were compared with entorhinal stages (Braak stages I-II). Dysregulation of genes associated with the actin cytoskeleton, proliferation, apoptosis, and ubiquitin-mediated proteolysis occurred at low Braak stages, while altered regulation of intracellular signaling pathways, including insulin, phosphatidylinositol 3-kinase (PI3K)/Akt, and mitogen-activated protein kinase (MAPK) pathways were primarily associated with high levels of Alzheimer-type pathology, and occurred at lower Braak stages in individuals with the APOEε4 allele. Our findings implicate astrocyte dysfunction in the pathogenesis of neurodegenerative pathology in the aging brain, and provide a basis for future candidate studies based on specific pathways.
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Affiliation(s)
- Julie E Simpson
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
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87
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Chauhan V, Howland M, Chen J, Kutzner B, Wilkins RC. Differential effects of alpha-particle radiation and x-irradiation on genes associated with apoptosis. Radiol Res Pract 2011; 2011:679806. [PMID: 22091383 PMCID: PMC3199915 DOI: 10.1155/2011/679806] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 04/05/2011] [Indexed: 01/13/2023] Open
Abstract
This study examined differential effects of alpha-(α-) particle radiation and X-rays on apoptosis and associated changes in gene expression. Human monocytic cells were exposed to α-particle radiation and X-rays from 0 to 1.5 Gy. Four days postexposure, cell death was measured by flow cytometry and 84 genes related to apoptosis were analyzed using real-time PCR. On average, 33% of the cells were apoptotic at 1.5 Gy of α-particle radiation. Transcript profiling showed statistical expression of 15 genes at all three doses tested. Cells exposed to X-rays were <5% apoptotic at ~1.5 Gy and induced less than a 2-fold expression in 6 apoptotic genes at the higher doses of radiation. Among these 6 genes, Fas and TNF-α were common to the α-irradiated cells. This data suggests that α-particle radiation initiates cell death by TNF-α and Fas activation and through intermediate signalling mediators that are distinct from X-irradiated cells.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Matthew Howland
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Jeremy Chen
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Barbara Kutzner
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Ruth C. Wilkins
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
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88
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Freise C, Ruehl M, Erben U, Neumann U, Seehofer D, Kim KY, Trowitzsch-Kienast W, Stroh T, Zeitz M, Somasundaram R. A hepatoprotective Lindera obtusiloba extract suppresses growth and attenuates insulin like growth factor-1 receptor signaling and NF-kappaB activity in human liver cancer cell lines. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 11:39. [PMID: 21569410 PMCID: PMC3117754 DOI: 10.1186/1472-6882-11-39] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 05/12/2011] [Indexed: 12/12/2022]
Abstract
Background In traditional Chinese and Korean medicine, an aqueous extract derived from wood and bark of the Japanese spice bush Lindera obtusiloba (L.obtusiloba) is applied to treat inflammations and chronic liver diseases including hepatocellular carcinoma. We previously demonstrated anti-fibrotic effects of L.obtusiloba extract in hepatic stellate cells. Thus, we here consequently examine anti-neoplastic effects of L.obtusiloba extract on human hepatocellular carcinoma (HCC) cell lines and the signaling pathways involved. Methods Four human HCC cell lines representing diverse stages of differentiation were treated with L.obtusiloba extract, standardized according to its known suppressive effects on proliferation and TGF-β-expression. Beside measurement of proliferation, invasion and apoptosis, effects on signal transduction and NF-κB-activity were determined. Results L.obtusiloba extract inhibited proliferation and induced apoptosis in all HCC cell lines and provoked a reduced basal and IGF-1-induced activation of the IGF-1R signaling cascade and a reduced transcriptional NF-κB-activity, particularly in the poorly differentiated SK-Hep1 cells. Pointing to anti-angiogenic effects, L.obtusiloba extract attenuated the basal and IGF-1-induced expression of hypoxia inducible factor-1α, vascular endothelial growth factor, peroxisome proliferator-activated receptor-γ, cyclooxygenase-2 and inducible nitric oxide synthase. Conclusions The traditional application of the extract is confirmed by our experimental data. Due to its potential to inhibit critical receptor tyrosine kinases involved in HCC progression via the IGF-1 signaling pathway and NF-κB, the standardized L.obtusiloba extract should be further analysed for its active compounds and explored as (complementary) treatment option for HCC.
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89
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Jamaluddin MS, Weakley SM, Zhang L, Kougias P, Lin PH, Yao Q, Chen C. miRNAs: roles and clinical applications in vascular disease. Expert Rev Mol Diagn 2011; 11:79-89. [PMID: 21171923 DOI: 10.1586/erm.10.103] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
miRNAs are small, endogenously expressed noncoding RNAs that regulate gene expression, mainly at the post-transcriptional level, via degradation or translational inhibition of their target mRNAs. Functionally, an individual miRNA can regulate the expression of multiple target genes. The study of miRNAs is rapidly growing and recent studies have revealed a significant role of miRNAs in vascular biology and disease. Many miRNAs are highly expressed in the vasculature, and their expression is dysregulated in diseased vessels. Several miRNAs have been found to be critical modulators of vascular pathologies, such as atherosclerosis, lipoprotein metabolism, inflammation, arterial remodeling, angiogenesis, smooth muscle cell regeneration, hypertension, apoptosis, neointimal hyperplasia and signal transduction pathways. Thus, miRNAs may serve as novel biomarkers and/or therapeutic targets for vascular disease. This article summarizes the current studies related to the disease correlations and functional roles of miRNAs in the vascular system and discusses the potential applications of miRNAs in vascular disease.
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Affiliation(s)
- Md Saha Jamaluddin
- Michael E DeBakey Department of Surgery, Baylor College of Medicine, One Baylor Plaza, Mail Stop: BCM391, Houston, TX 77030, USA
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90
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Kyathanahalli CN, Kowluru A. A farnesylated G-protein suppresses Akt phosphorylation in INS 832/13 cells and normal rat islets: regulation by pertussis toxin and PGE₂. Biochem Pharmacol 2011; 81:1237-47. [PMID: 21406184 DOI: 10.1016/j.bcp.2011.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 03/01/2011] [Accepted: 03/03/2011] [Indexed: 12/31/2022]
Abstract
Protein isoprenylation constitutes incorporation of either 15-carbon farnesyl or 20-carbon geranylgeranyl derivative of mevalonic acid onto the C-terminal cysteine, culminating in increased hydrophobicity of the modified proteins for optimal membrane anchoring and interaction with their respective effectors. Emerging evidence confirms the participatory role of prenylated proteins in pancreatic β-cell function including insulin secretion. Herein, we investigated the putative regulatory roles of protein farnesylation in cell survival signaling pathways in insulin-secreting INS 832/13 cells and normal rodent islets, specifically at the level of protein kinase-B/Akt phosphorylation induced by insulin-like growth factor [IGF-1]. Selective inhibitors of farnesylation [e.g., FTI-277 or FTI-2628] or knockdown of the β-subunit of farnesyl transferase by siRNA significantly increased Akt activation under basal and IGF-1-stimulated conditions. Consequentially, the relative abundance of phosphorylated FoxO1 and Bad were increased implicating inactivation of critical components of the cell death machinery. In addition, FTI-induced Akt activation was attenuated by the PI3-kinase inhibitor, LY294002. Exposure of INS 832/13 cells to pertussis toxin [PTx] markedly potentiated Akt phosphorylation suggesting involvement of a PTx-sensitive G-protein in this signaling axis. Furthermore, prostaglandin E₂, a known agonist of inhibitory G-proteins, significantly attenuated FTI-induced Akt phosphorylation. Taken together, our findings suggest expression of a farnesylated G-protein in INS 832/13 cells and normal rat islets, which appear to suppress Akt activation and subsequent cell survival signaling steps. Potential regulatory roles of the islet endogenous protein kinase-B inhibitory protein [Probin] in islet function are discussed.
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Affiliation(s)
- Chandrashekara N Kyathanahalli
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, 259 Mack Avenue, Detroit, MI 48202, USA
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91
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Kuo WW, Hsu TC, Chain MH, Lai CH, Wang WH, Tsai FJ, Tsai CH, Wu CH, Huang CY, Tzang BS. Attenuated cardiac mitochondrial-dependent apoptotic effects by li-fu formula in hamsters fed with a hypercholesterol diet. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 2011:530345. [PMID: 19939950 PMCID: PMC3135794 DOI: 10.1093/ecam/nep182] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Accepted: 10/02/2009] [Indexed: 11/13/2022]
Abstract
Apoptosis involves in the pathogenesis of various cardiac abnormalities. This study intends to evaluate the effects of Li-Fu formula on cardiac apoptosis induced by hyper-cholesterol diet. Twenty-four male Golden Syrian hamsters were randomly divided into Control, Cholesterol and Li-Fu formula groups. Histopathological analysis, western blotting and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays were performed to measure the effects of Li-Fu formula on left ventricle. Significantly reduced TUNEL-positive cells and mitochondria- dependent apoptosis were observed in the left ventricle of hamsters from Li-Fu formula group compared to the Cholesterol group. Additionally, induced cardiac insulin like growth factor I receptor (IGFIR)-dependent survival pathway was detected in the Li-Fu formula group compared to the Cholesterol group. Besides, minor fibrosis, increased collagen deposition, and myofibril disarray was detected in the Cholesterol group, whereas the reductions of collagen deposition and myofibril disarray were observed in the Li-Fu formula group. This study demonstrated that Li-Fu formula not only reduced the mitochondria-dependent apoptosis and fibrosis, but also enhanced the IGF-I survival pathway in the left ventricle from high cholesterol-fed hamsters. We suggest the protective effects of Li-Fu formula on cardiac apoptosis and therapeutic potentials against cardiovascular disease.
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Affiliation(s)
- Wei-Wen Kuo
- Department of Biological Science and Technology, China Medical University, Taiwan
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92
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Insulin-like growth factor I receptor density on CD4+T-lymphocytes from active early steroid- and DMARD-naïve rheumatoid arthritis patients is up-regulated and not influenced by 1 year of clinically effective treatment. Rheumatol Int 2011; 32:501-4. [PMID: 21246373 DOI: 10.1007/s00296-010-1683-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 11/14/2010] [Indexed: 10/18/2022]
Abstract
The IGF-IR density on CD4+T-lymphocytes was studied using flow cytometry in 40 early steroid- and DMARD-naïve rheumatoid arthritis (RA) patients before and after 52 weeks of treatment with methotrexate+placebo or methotrexate+cyclosporine A and in 15 controls. RA patients had increased IGF-IR density on CD4+T-lymphocytes at week 0 and week 52, irrespective of treatment. IGF-IR-positive CD4+T-lymphocytes fraction decreased during treatment, but neither at week 0 nor at week 52 did it differ from healthy controls. No correlations were found to disease activity parameters.
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93
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Pavlikova N, Arukwe A. Immune-regulatory transcriptional responses in multiple organs of Atlantic salmon after tributyltin exposure, alone or in combination with forskolin. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2011; 74:478-493. [PMID: 21391093 DOI: 10.1080/15287394.2011.550558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Tributyltin (TBT) is a widespread marine pollutant that influences physiological conditions of fish and other aquatic organisms. In addition to effects on reproduction, the immune system has been proposed as a possible target for TBT effects. In the present study, the effects of TBT exposure were examined on the expression of genes involved in immune system compentence in liver and head kidney of Atlantic salmon, in the presence and absence of a second-messenger activator (forskolin). Juvenile salmon were force-fed a diet containing TBT (0-solvent control, 0.1, 1, or 10 mg/kg fish) for 72 h. Consequently, fish from the control group and 10-mg/kg TBT group were exposed to the adenylate cyclase (AC) activator forskolin (200 μg/L) for 2 or 4 h. Forskolin was selected for this study because it is known to exhibit potent immune system enhancement by activating macrophages and lymphocytes. After sacrifice, liver and head kidney were sampled and transcript changes for interleukin (IL)-1β, IL-10, transforming growth factor (TGF) β, interferon (INF) α, INFγ, tumor necrosis factor (TNF) α, Mx3, and insulin-like growth factor (IGF)-1 were determined in both tissues by quantitative polymerase chain reaction (qPCR) using gene-specific primers. TBT, when given alone and also in combination with forskolin, decreased IL-1β, TNFα, IFNγ, IFNα, Mx3, and IGF-1 gene expression. In contrast, IL-10 and TGFβ transcripts were increased after TBT exposure alone and also in combination with forskolin. Generally, these effects were largely dependent on TBT dose and time of exposure when given in combination with forskolin. Overall, our findings suggest a possible immunomodulatory effect of TBT, possibly involving cAMP activation.
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Affiliation(s)
- Nela Pavlikova
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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94
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Boucher J, Macotela Y, Bezy O, Mori MA, Kriauciunas K, Kahn CR. A kinase-independent role for unoccupied insulin and IGF-1 receptors in the control of apoptosis. Sci Signal 2010; 3:ra87. [PMID: 21139139 DOI: 10.1126/scisignal.2001173] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Insulin and insulin-like growth factor 1 (IGF-1) act as antiapoptotic hormones. We found that, unexpectedly, double-knockout (DKO) cells that lacked both insulin and IGF-1 receptors (IR and IGF1R, respectively) were resistant to apoptosis induced through either the intrinsic or the extrinsic pathway. This resistance to apoptosis was associated with decreased abundance of the proapoptotic protein Bax and increases in abundance of the antiapoptotic proteins Bcl-2, Bcl-xL, XIAP, and Flip. These changes in protein abundance involved primarily posttranscriptional mechanisms. Restoration of IR or IGF1R to DKO cells also restored their sensitivity to apoptosis. Notably, expression of a catalytically inactive mutant form of the IR also restored susceptibility to apoptosis. Thus, IR and IGF1R have bidirectional roles in the control of cell survival and can be viewed as dependence receptors. Insulin and IGF-1 binding stimulates receptor tyrosine kinase activity and blocks apoptosis, whereas unliganded IR and IGF1R, acting through a mechanism independent of their catalytic activity, exert a permissive effect on cell death.
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Affiliation(s)
- Jeremie Boucher
- Joslin Diabetes Center and Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02215, USA
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95
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Corrêa LL, Lima GAB, Paiva HBDM, Silva CMDS, Cavallieri SA, Miranda LCDD, Gadelha MR. Prostate cancer and acromegaly. ACTA ACUST UNITED AC 2010; 53:963-8. [PMID: 20126848 DOI: 10.1590/s0004-27302009000800009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acromegalic patients have an increased prevalence of prostatic disorders compared to age-matched healthy subjects. Increased size of the whole prostate or the transitional zone, together with an elevated incidence of other structural changes, such as nodules, cysts, and calcifications, have been reported. Prostate enlargement in young acromegalic patients with low testosterone levels due to central hypogonadism supports the hypothesis that chronic GH and IGF-I excess cause prostate hyperplasia. The relationship between prostatic carcinoma and acromegaly is, until now, only circumstantial. Long-term follow-up of these patients is necessary since epidemiologic studies showed association between serum IGF-I levels in the upper normal limit and prostate cancer in the general population. This review approaches prostate diseases in patients with acromegaly.
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Affiliation(s)
- Lívia L Corrêa
- Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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Lima GAB, Corrêa LL, Gabrich R, Miranda LCDD, Gadelha MR. IGF-I, insulin and prostate cancer. ACTA ACUST UNITED AC 2010; 53:969-75. [PMID: 20126849 DOI: 10.1590/s0004-27302009000800010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Accepted: 11/08/2009] [Indexed: 11/22/2022]
Abstract
Prostate cancer is the second most frequent malignancy diagnosed in adult men. Androgens are considered the primary growth factors for prostate normal and cancer cells. However, other non-androgenic growth factors are involved in the growth regulation of prostate cancer cells. The association between IGF-I and prostate cancer risk is well established. However, there is no evidence that the measurement of IGF-I enhances the specificity of prostate cancer detection beyond that achievable by serum prostate-specific antigen (PSA) levels. Until now, there is no consensus on the possible association between IGFBP-3 and prostate cancer risk. Although not well established, it seems that high insulin levels are particularly associated with risk of aggressive prostatic tumours. This review describes the physiopathological basis, epidemiological evidence, and animal models that support the association of the IGFs family and insulin with prostate cancer. It also describes the potential therapies targeting these growth factors that, in the future, can be used to treat patients with prostate cancer.
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Affiliation(s)
- Giovanna A Balarini Lima
- Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
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97
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Gridelli C, Rossi A, Bareschino MA, Schettino C, Sacco PC, Maione P. The potential role of insulin-like growth factor receptor inhibitors in the treatment of advanced non-small cell lung cancer. Expert Opin Investig Drugs 2010; 19:631-9. [PMID: 20367288 DOI: 10.1517/13543781003767434] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Lung cancer is the leading cause of cancer-related mortality worldwide. NSCLC accounts for > 80% of all lung cancers. The treatment of advanced fit NSCLC patients seems to have reached a plateau. Considerable efforts have been initiated to identify new biological agents. AREAS COVERED IN THIS REVIEW Diagnosis of NSCLC histotype is becoming extremely important to address treatment. While non-squamous histology could start to benefit from the administration of several new drugs only recently, non-adenocarcinoma subtype seems to benefit from the administration of figitumumab (CP-751,871) a fully human anti-IGF 1 receptor (IGF-1R) mAb. In this paper, we reviewed the IGF-1R pathway and its inhibitors. WHAT THE READER WILL GAIN Approaches targeting IGF-1R include small-molecule IGF-1R tyrosine kinase inhibitors (TKIs), which are in preclinical and early clinical phases of development, and the mAbs, among which figitumumab is being investigated in Phase III trials of advanced NSCLC. TAKE HOME MESSAGE Figitumumab reported interesting results in the treatment of advanced non-adenocarcinoma NSCLC patients. Overall, in order to administer the optimal treatment to patients, a more definite histological diagnosis is mandatory.
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Affiliation(s)
- Cesare Gridelli
- SG Moscati Hospital, Division of Medical Oncology, Avellino, Italy.
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98
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Vogel R, Garten A, Klammt J, Barnikol-Oettler A, Kiess W. Activation of Erk1/2 phosphorylation but not of Akt/Pkb through an inducible CSF1R/IRR-receptor construct in INS-1E beta-cells. Arch Physiol Biochem 2010; 116:128-36. [PMID: 20536329 DOI: 10.3109/13813455.2010.494671] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONTEXT The insulin receptor-related receptor (IRR) is an orphan receptor belonging to the insulin receptor (IR) family. Despite its unknown function, the specific tissue expression and the high sequence homology with the IR and the insulin-like growth factor 1 receptor (IGF1R) suggest a biological role in beta-cells. OBJECTIVES In this study we investigated the influence of a stimulatable IRR-tyrosine kinase on major IR/IGF1R signaling pathways and on proliferation and apoptosis of INS-1E beta-cells. METHODS INS-1E cells were stably transfected with a colony stimulating factor 1 receptor (CSF1R)/IRR construct activated by a macrophage colony stimulating factor. RESULTS AND CONCLUSION After stimulation the construct showed time and dose dependent autophosphorylation and transient extracellular signal regulated kinase 1/2 activation. Protein kinase b was not phosphorylated and also an effect on proliferation and apoptosis of INS-1E could not be demonstrated. Thus, no obvious biologic function of the IRR is present in INS-1E beta-cells.
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Affiliation(s)
- Rico Vogel
- Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany
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99
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Molecular distinction between physiological and pathological cardiac hypertrophy: experimental findings and therapeutic strategies. Pharmacol Ther 2010; 128:191-227. [PMID: 20438756 DOI: 10.1016/j.pharmthera.2010.04.005] [Citation(s) in RCA: 604] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cardiac hypertrophy can be defined as an increase in heart mass. Pathological cardiac hypertrophy (heart growth that occurs in settings of disease, e.g. hypertension) is a key risk factor for heart failure. Pathological hypertrophy is associated with increased interstitial fibrosis, cell death and cardiac dysfunction. In contrast, physiological cardiac hypertrophy (heart growth that occurs in response to chronic exercise training, i.e. the 'athlete's heart') is reversible and is characterized by normal cardiac morphology (i.e. no fibrosis or apoptosis) and normal or enhanced cardiac function. Given that there are clear functional, structural, metabolic and molecular differences between pathological and physiological hypertrophy, a key question in cardiovascular medicine is whether mechanisms responsible for enhancing function of the athlete's heart can be exploited to benefit patients with pathological hypertrophy and heart failure. This review summarizes key experimental findings that have contributed to our understanding of pathological and physiological heart growth. In particular, we focus on signaling pathways that play a causal role in the development of pathological and physiological hypertrophy. We discuss molecular mechanisms associated with features of cardiac hypertrophy, including protein synthesis, sarcomeric organization, fibrosis, cell death and energy metabolism and provide a summary of profiling studies that have examined genes, microRNAs and proteins that are differentially expressed in models of pathological and physiological hypertrophy. How gender and sex hormones affect cardiac hypertrophy is also discussed. Finally, we explore how knowledge of molecular mechanisms underlying pathological and physiological hypertrophy may influence therapeutic strategies for the treatment of cardiovascular disease and heart failure.
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100
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Frémin C, Meloche S. From basic research to clinical development of MEK1/2 inhibitors for cancer therapy. J Hematol Oncol 2010; 3:8. [PMID: 20149254 PMCID: PMC2830959 DOI: 10.1186/1756-8722-3-8] [Citation(s) in RCA: 179] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Accepted: 02/11/2010] [Indexed: 11/10/2022] Open
Abstract
The Ras-dependent Raf/MEK/ERK1/2 mitogen-activated protein (MAP) kinase signaling pathway is a major regulator of cell proliferation and survival. Not surprisingly, hyperactivation of this pathway is frequently observed in human malignancies as a result of aberrant activation of receptor tyrosine kinases or gain-of-function mutations in RAS or RAF genes. Components of the ERK1/2 pathway are therefore viewed as attractive candidates for the development of targeted therapies of cancer. In this article, we briefly review the basic research that has laid the groundwork for the clinical development of small molecules inhibitors of the ERK1/2 pathway. We then present the current state of clinical evaluation of MEK1/2 inhibitors in cancer and discuss challenges ahead.
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Affiliation(s)
- Christophe Frémin
- Institut de Recherche en Immunologie et Cancérologie and Department of Pharmacology, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
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