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Ahmed M, Biswas T, Mondal S. The strategic involvement of IRS in cancer progression. Biochem Biophys Res Commun 2023; 680:141-160. [PMID: 37738904 DOI: 10.1016/j.bbrc.2023.09.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/13/2023] [Accepted: 09/15/2023] [Indexed: 09/24/2023]
Abstract
Insulin Receptor Substrate (IRS), an intracellular molecule devoid of an intrinsic kinase activity, is activated upon binding to IR which thereby works as a scaffold, organizing all signaling complexes and initiating the signaling process downstream. The level of IRS proteins and their stability in the cell is mostly maintained through the phosphorylation status of their tyrosine and serine residues. IRS is positively regulated by phosphorylation of its Tyr residues whereas a Ser residue phosphorylation attenuates it, although there exist some exceptions as well. Other post-translational modifications like O-linked glycosylation, N-linked glycosylation and acetylation also play a prominent role in IRS regulation. Since the discovery of the Warburg effect, people have been curious to find out all possible signaling networks and molecules that could lead to cancer and no doubt, the insulin signaling pathway is identified as one such pathway, which is highly deregulated in cancers. Eminent studies reveal that IRS is a pertinent regulator of cancer and is highly overexpressed in the five most commonly occurring cancers namely- Prostate, Ovarian, Breast, Colon and Lung cancers. IRS1 and IRS2 family members are actively involved in the progression, invasion and metastasis of these cancers. Recently, less studied IRS4 has also emerged as a contributor in ovarian, breast, colorectal and lung cancer, but no such studies related to IRS4 are found in Prostate cancer. The involvement of other IRS family members in cancer is still undiscovered and so paves the way for further exploration. This review is a time-lapse study of IRSs in the context of cancer done over the past two decades and it highlights all the major discoveries made till date, in these cancers from the perspective of IRS.
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Affiliation(s)
- Mehnaz Ahmed
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata, 700073, West Bengal, India
| | - Tannishtha Biswas
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata, 700073, West Bengal, India
| | - Susmita Mondal
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata, 700073, West Bengal, India.
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2
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Bhattacharjee A, Pranto SMAM, Ahammad I, Chowdhury ZM, Juliana FM, Das KC, Keya CA, Salimullah M. High risk genetic variants of human insulin receptor substrate 1(IRS1) infer structural instability and functional interference. J Biomol Struct Dyn 2023; 41:15150-15164. [PMID: 36907599 DOI: 10.1080/07391102.2023.2187232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/23/2023] [Indexed: 03/14/2023]
Abstract
Insulin receptor substrate 1(IRS1) is a signaling adapter protein encoded by the IRS1 gene. This protein delivers signals from insulin and insulin-like growth factor-1(IGF-1) receptors to the phosphatidylinositol 3-kinases (P13K)/protein kinase B (Akt) and Extracellular signal-regulated kinases (Erk) - Mitogen-activated protein (MAP) kinase pathways, which regulate particular cellular processes. Mutations in this gene have been linked to type 2 diabetes mellitus, a heightened risk of insulin resistance, and an increased likelihood of developing a number of different malignancies. The structure and function of IRS1 could be severely compromised as a result of single nucleotide polymorphism (SNP) type genetic variants. In this study, we focused on identification of the most harmful non-synonymous SNPs (nsSNPs) of the IRS1 gene as well as prediction of their structural and functional consequences. Six different algorithms made the initial prediction that 59 of the 1142 IRS1 nsSNPs would have a negative impact on the protein structure. In-depth evaluations detected 26 nsSNPs located inside the functional domains of IRS1. Following that, 16 nsSNPs were identified as more harmful based on conservation profile, hydrophobic interaction, surface accessibility, homology modelling, and inter-atomic interactions. Following an in-depth analysis of protein stability, M249T (rs373826433), I223T (rs1939785175) and V204G (rs1574667052) were identified as three most deleterious SNPs and were subjected to molecular dynamics simulation for further insights. These findings will help us understand the implications for disease susceptibility, cancer progression, and the efficacy of therapeutic development against IRS1 gene mutants.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | - S M Al Muied Pranto
- Department of Biochemistry & Molecular Biology, Jahangirnagar University, Savar, Bangladesh
| | - Ishtiaque Ahammad
- Bioinformatics Division, National Institute of Biotechnology, Savar, Bangladesh
| | | | - Farha Matin Juliana
- Department of Biochemistry & Molecular Biology, Jahangirnagar University, Savar, Bangladesh
| | - Keshob Chandra Das
- Molecular Biotechnology Division, National Institute of Biotechnology, Savar, Bangladesh
| | - Chaman Ara Keya
- Department of Biochemistry and Microbiology, North South University, Bashundhara, Bangladesh
| | - Md Salimullah
- Molecular Biotechnology Division, National Institute of Biotechnology, Savar, Bangladesh
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3
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Martínez Báez A, Castro Romero I, Chihu Amparan L, Castañeda JR, Ayala G. The Insulin Receptor Substrate 2 Mediates the Action of Insulin on HeLa Cell Migration via the PI3K/Akt Signaling Pathway. Curr Issues Mol Biol 2023; 45:2296-2308. [PMID: 36975518 PMCID: PMC10047682 DOI: 10.3390/cimb45030148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/14/2023] [Accepted: 02/22/2023] [Indexed: 03/12/2023] Open
Abstract
Insulin signaling plays an important role in the development and progression of cancer since it is involved in proliferation and migration processes. It has been shown that the A isoform of the insulin receptor (IR-A) is often overexpressed, and its stimulation induces changes in the expression of the insulin receptor substrates (IRS-1 and IRS-2), which are expressed differently in the different types of cancer. We study the participation of the insulin substrates IRS-1 and IRS-2 in the insulin signaling pathway in response to insulin and their involvement in the proliferation and migration of the cervical cancer cell line. Our results showed that under basal conditions, the IR-A isoform was predominantly expressed. Stimulation of HeLa cells with 50 nM insulin led to the phosphorylation of IR-A, showing a statistically significant increase at 30 min (p ≤ 0.05). Stimulation of HeLa cells with insulin induces PI3K and AKT phosphorylation through the activation of IRS2, but not IRS1. While PI3K reached the highest level at 30 min after treatment (p ≤ 0.05), AKT had the highest levels from 15 min (p ≤ 0.05) and remained constant for 6 h. ERK1 and ERK2 expression was also observed, but only ERK2 was phosphorylated in a time-dependent manner, reaching a maximum peak 5 min after insulin stimulation. Although no effect on cell proliferation was observed, insulin stimulation of HeLa cells markedly promoted cell migration.
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Affiliation(s)
- Anabel Martínez Báez
- Infection Disease Research Center, National Institute of Public Health, Cuernavaca 62100, Mexico
| | - Ivone Castro Romero
- Subdirectorate of Training and Medical Update, Secretary of Health, Mexico City 06900, Mexico
| | - Lilia Chihu Amparan
- Infection Disease Research Center, National Institute of Public Health, Cuernavaca 62100, Mexico
| | | | - Guadalupe Ayala
- Infection Disease Research Center, National Institute of Public Health, Cuernavaca 62100, Mexico
- Correspondence:
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4
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Insulin receptor substrate 1(IRS1) is related with lymph node metastases and prognosis in esophageal squamous cell carcinoma. Gene 2022; 835:146651. [PMID: 35688292 DOI: 10.1016/j.gene.2022.146651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/04/2022] [Accepted: 06/02/2022] [Indexed: 11/20/2022]
Abstract
Esophageal squamous cell carcinoma (ESCC) is one of the leading causes of cancer-related mortality globally with a high risk of lymph node metastasis (LNM). In this study, weighted gene co-expression network analysis (WGCNA) showed the identification of 10 modules among which the significant module (turquoise), including 1352 genes, was correlated with LNM. A group 52 overlapping differentially expressed genes (DEGs) was identified based on the comparison of turquoise module with GSE23400 and GSE20347 datasets. Using Ctyohubba plugin, we identified 7 hub genes (ACTG2, SORBS1, MYH11, CXCL12, CNN1, IRS1 and CXCL8). IRS1 displayed significant correlation with metastasis. The decreased expression of IRS1 was also a predictor of poor OS of ESCC patients whereas the hub genes namely ACTG2, MYH11, CXCL8, CXCL12, IRS1 and CNN1 were associated with RFS of ESCC patients. These findings suggest that the altered expression of these hub genes are associated with prognosis and thus can be used as potential biomarkers for ESCC. Moreover, immunohistochemical staining and cell functional experiments displayed that the overexpression of IRS1 was negatively associated with metastasis in ESCC. In general, our research revealed several novel genes in ESCC especially the association of IRS1 with LNM in ESCC, which could provide novel insights into the initiation and progression of ESCC.
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Lomperta K, Jakubowska K, Grudzinska M, Kanczuga-Koda L, Wincewicz A, Surmacz E, Sulkowski S, Koda M. Insulin receptor substrate 1 may play divergent roles in human colorectal cancer development and progression. World J Gastroenterol 2020; 26:4140-4150. [PMID: 32821075 PMCID: PMC7403795 DOI: 10.3748/wjg.v26.i28.4140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/26/2020] [Accepted: 07/16/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Despite effective prevention and screening methods, the incidence and mortality rates associated with colorectal cancer (CRC) are still high. Insulin receptor substrate 1 (IRS-1), a signaling molecule involved in cell proliferation, survival and metabolic responses has been implicated in carcinogenic processes in various cellular and animal models. However, the role of IRS-1 in CRC biology and its value as a clinical CRC biomarker has not been well defined.
AIM To evaluate if and how IRS-1 expression and its associations with the apoptotic and proliferation tumor markers, Bax, Bcl-xL and Ki-67 are related to clinicopathological features in human CRC.
METHODS The expression of IRS-1, Bax, Bcl-xL and Ki-67 proteins was assessed in tissue samples obtained from 127 patients with primary CRC using immunohistochemical methods. The assays were performed using specific antibodies against IRS-1, Bax, Bcl-xL, Ki-67. The associations between the expression of IRS-1, Bax, Bcl-xL, Ki-67 were analyzed in relation to clinicopathological parameters, i.e., patient age, sex, primary localization of tumor, histopathological type, grading, staging and lymph node spread. Correlations between variables were examined by Spearman rank correlation test and Fisher exact test with a level of significance at P < 0.05.
RESULTS Immunohistochemical analysis of 127 CRC tissue samples revealed weak cytoplasmatic staining for IRS-1 in 66 CRC sections and strong cytoplasmatic staining in 61 cases. IRS-1 expression at any level in primary CRC was associated with tumor grade (69% in moderately differentiated tumors, G2 vs 31% in poorly differentiated tumors, G3) and with histological type (81.9% in adenocarcinoma vs 18.1% in adenocarcinoma with mucosal component cases). Strong IRS-1 positivity was observed more frequently in adenocarcinoma cases (95.1%) and in moderately differentiated tumors (85.2%). We also found statistically significant correlations between expression of IRS-1 and both Bax and Bcl-xL in all CRC cases examined. The relationships between studied proteins were related to clinicopathological parameters of CRC. No significant correlation between the expression of IRS-1 and proliferation marker Ki-67, excluding early stage tumors, where the correlation was positive and on a high level (P = 0.043, r = 0.723).
CONCLUSION This study suggests that IRS-1 is co-expressed with both pro- and antiapoptotic markers and all these proteins are more prevalent in more differentiated CRC than in poorly differentiated CRC.
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Affiliation(s)
- Karolina Lomperta
- Department of General Pathomorphology, Medical University of Bialystok, Bialystok 15269, Poland
| | - Katarzyna Jakubowska
- Department of Pathomorphology, Comprehensive Cancer Centre, Bialystok 15027, Poland
| | - Malgorzata Grudzinska
- Department of General Pathomorphology, Medical University of Bialystok, Bialystok 15269, Poland
| | - Luiza Kanczuga-Koda
- Department of Pathomorphology, Comprehensive Cancer Centre, Bialystok 15027, Poland
| | - Andrzej Wincewicz
- Department of Pathology, Nonpublic Health Care Unit, Kielce 25734, Poland
| | - Eva Surmacz
- Allysta Pharmaceuticals Incorporated, Belmont, CA 94002, United States
| | - Stanislaw Sulkowski
- Department of General Pathomorphology, Medical University of Bialystok, Bialystok 15269, Poland
| | - Mariusz Koda
- Department of General Pathomorphology, Medical University of Bialystok, Bialystok 15269, Poland
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Frezza V, Fierro C, Gatti E, Peschiaroli A, Lena AM, Petruzzelli MA, Candi E, Anemona L, Mauriello A, Pelicci PG, Melino G, Bernassola F. ΔNp63 promotes IGF1 signalling through IRS1 in squamous cell carcinoma. Aging (Albany NY) 2019; 10:4224-4240. [PMID: 30594912 PMCID: PMC6326668 DOI: 10.18632/aging.101725] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
Abstract
Accumulating evidence has proved that deregulation of ΔNp63 expression plays an oncogenic role in head and neck squamous cell carcinomas (HNSCCs). Besides p63, the type 1-insulin-like growth factor (IGF) signalling pathway has been implicated in HNSCC development and progression. Most insulin/IGF1 signalling converges intracellularly onto the protein adaptor insulin receptor substrate-1 (IRS-1) that transmits signals from the receptor to downstream effectors, including the PI3K/AKT and the MAPK kinase pathways, which, ultimately, promote proliferation, invasion, and cell survival. Here we report that p63 directly controls IRS1 transcription and cellular abundance and fosters the PI3K/AKT and MAPK downstream signalling pathways. Inactivation of ΔNp63 expression indeed reduces tumour cell responsiveness to IGF1 stimulation, and inhibits the growth potential of HNSCC cells. In addition, a positive correlation was observed between p63 and IRS1 expression in human HNSCC tissue arrays and in publicly available gene expression data. Our findings indicate that aberrant expression of ΔNp63 in HNSSC may act as an oncogenic stimulus by altering the IGF signalling pathway.
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Affiliation(s)
- Valentina Frezza
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy
| | - Claudia Fierro
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy
| | - Elena Gatti
- Department of Experimental Oncology European Institute of Oncology, Milan 20139, Italy
| | - Angelo Peschiaroli
- National Research Council of Italy Institute of Translational Pharmacology (IFT-CNR), Rome 00133, Italy
| | - Anna Maria Lena
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy
| | | | - Eleonora Candi
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy.,Istituto Dermopatico dell'Immacolata, IRCCS,, Rome 00163, Italy
| | - Lucia Anemona
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy
| | - Alessandro Mauriello
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy
| | - Pier Giuseppe Pelicci
- Department of Experimental Oncology European Institute of Oncology, Milan 20139, Italy
| | - Gerry Melino
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy.,Medical Research Council, Toxicology Unit, University of Cambridge, Leicester LE1 9HN, UK
| | - Francesca Bernassola
- Department of Experimental Medicine, TOR University of Rome "Tor Vergata", Rome 00133, Italy
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7
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Luo J, Feng J, Wen Q, Qoyawayma C, Wang W, Chen L, Lu J, Zhan Y, Xu L, Zang H, Fan S, Chu S. Elevated expression of IRS-1 associates with phosphorylated Akt expression and predicts poor prognosis of breast invasive ductal carcinoma. Hum Pathol 2018; 79:9-17. [DOI: 10.1016/j.humpath.2018.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 03/03/2018] [Accepted: 03/09/2018] [Indexed: 01/14/2023]
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8
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Sun X, Chen Y, Tan J, Qi X. Serum IRS-1 acts as a novel biomarker for diagnosis in patients with nasopharyngeal carcinoma. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2018; 11:3685-3690. [PMID: 31949750 PMCID: PMC6962894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 11/25/2015] [Indexed: 06/10/2023]
Abstract
BACKGROUND Nasopharyngeal carcinoma (NPC) is a major head and neck cancer with high occurrence in Southeast Asia and southern China. Insulin receptor substrate 1 (IRS-1) plays an important role in the development, progression, invasion and metastasis of tumors. The purpose of this study was to evaluate whether IRS-1 could be used as biomarkers for the diagnosis of NPC through measuring their expression and assess their relationship with clinical pathological factors. METHODS Quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) and Western blot were used to analyze the expression of IRS-1 in 133 NPC patients and 104 healthy controls. The relationship between IRS-1 expression and clinicopathological characteristics in NPC was estimated through chi-square test. We calculated diagnostic values of serum IRS-1 expression by receiver operating characteristic (ROC) curve. RESULTS This study reports that IRS-1 protein was weakly expressed in NPC specimens, but highly in healthy controls. Serum IRS-1 were up-regulation in NPC patients compared with healthy controls. Their up-regulation was significantly correlated with lymph node status (P=0.029). Furthermore, the value of the area under the receiver-operating characteristic curve (AUC-ROC) was 0.907. The optimal cutoff value was 2.255, providing a sensitivity of 88.0% and a specificity of 77.9% in differentiating NPC patients from healthy controls. CONCLUSION Our data indicates that serum IRS-1 might increase the sensitivity and accuracy in diagnosis of NPC, and may be a potential target for diagnosis and gene therapy.
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Affiliation(s)
- Xiuxia Sun
- Department of Otorhinolaryngology, Affiliated Hospital of Weifang Medical CollegeWeifang, Shandong, China
| | - Yongbao Chen
- Department of Otorhinolaryngology, Yishui Central Hospital of LinyiShandong, China
| | - Jifang Tan
- Department of Otorhinolaryngology, Air Force Jinan to Recruit Students in Flight TrainingJinan, Shandong, China
| | - Xuanchang Qi
- Department of Otorhinolaryngology, Affiliated Hospital of Weifang Medical CollegeWeifang, Shandong, China
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9
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Identification of a Novel Invasion-Promoting Region in Insulin Receptor Substrate 2. Mol Cell Biol 2018; 38:MCB.00590-17. [PMID: 29685905 DOI: 10.1128/mcb.00590-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 04/15/2018] [Indexed: 12/13/2022] Open
Abstract
Although the insulin receptor substrate (IRS) proteins IRS1 and IRS2 share considerable homology and activate common signaling pathways, their contributions to breast cancer are distinct. IRS1 has been implicated in the proliferation and survival of breast tumor cells. In contrast, IRS2 facilitates glycolysis, invasion, and metastasis. To determine the mechanistic basis for IRS2-dependent functions, we investigated unique structural features of IRS2 that are required for invasion. Our studies revealed that the ability of IRS2 to promote invasion is dependent upon upstream insulin-like growth factor 1 receptor (IGF-1R)/insulin receptor (IR) activation and the recruitment and activation of phosphatidylinositol 3-kinase (PI3K), functions shared with IRS1. In addition, a 174-amino-acid region in the IRS2 C-terminal tail, which is not conserved in IRS1, is also required for IRS2-mediated invasion. Importantly, this "invasion (INV) region" is sufficient to confer invasion-promoting ability when swapped into IRS1. However, the INV region is not required for the IRS2-dependent regulation of glucose uptake. Bone morphogenetic protein 2-inducible kinase (BMP2K) binds to the INV region and contributes to IRS2-dependent invasion. Taken together, our data advance the mechanistic understanding of how IRS2 regulates invasion and reveal that IRS2 functions important for cancer can be independently targeted without interfering with the metabolic activities of this adaptor protein.
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10
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Kumar AS, Rayala SK, Venkatraman G. Targeting IGF1R pathway in cancer with microRNAs: How close are we? RNA Biol 2018; 15:320-326. [PMID: 28613101 DOI: 10.1080/15476286.2017.1338240] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cancer of the head and neck are the most common cancers in India and account for 30% of all cancers. At molecular level, it could be attributed to the overexpression of growth factors like IGF1-R, EGFR, VEGF-R and deregulation of cell cycle regulators and tumor suppressors. IGF1-R is an emerging target in head and neck cancer treatment, because of its reported role in tumor development, progression and metastasis. IGF1R targeted agents are in advanced stages of clinical development. Nevertheless, these agents suffer from several disadvantages including acquired resistance and toxic side effects. Hence there is a need for developing newer agents targeting not only the receptor but also its downstream signaling. miRNAs are considered as master regulators of gene expression of multiple genes and has been widely reported to be a promising therapeutic strategy. This review discusses the present status of research in both these arenas and emphasizes the role of miRNA as a promising agent for biologic therapy.
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Affiliation(s)
- Arathy S Kumar
- a Department of Biotechnology , Indian Institute of Technology, Madras (IIT M) , Chennai , India
| | - Suresh K Rayala
- a Department of Biotechnology , Indian Institute of Technology, Madras (IIT M) , Chennai , India
| | - Ganesh Venkatraman
- b Department of Human Genetics , College of Biomedical Sciences, Technology & Research, Sri Ramachandra University , Porur, Chennai , India
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11
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Mercado-Matos J, Clark JL, Piper AJ, Janusis J, Shaw LM. Differential involvement of the microtubule cytoskeleton in insulin receptor substrate 1 (IRS-1) and IRS-2 signaling to AKT determines the response to microtubule disruption in breast carcinoma cells. J Biol Chem 2017; 292:7806-7816. [PMID: 28320862 DOI: 10.1074/jbc.m117.785832] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Indexed: 01/17/2023] Open
Abstract
The insulin receptor substrate (IRS) proteins serve as essential signaling intermediates for the activation of PI3K by both the insulin-like growth factor 1 receptor (IGF-1R) and its close family member, the insulin receptor (IR). Although IRS-1 and IRS-2 share significant homology, they regulate distinct cellular responses downstream of these receptors and play divergent roles in breast cancer. To investigate the mechanism by which signaling through IRS-1 and IRS-2 results in differential outcomes, we assessed the involvement of the microtubule cytoskeleton in IRS-dependent signaling. Treatment with drugs that either stabilize or disrupt microtubules reveal that an intact microtubule cytoskeleton contributes to IRS-2- but not IRS-1-mediated activation of AKT by IGF-1. Proximal IGF-1R signaling events, including IRS tyrosine phosphorylation and recruitment of PI3K, are not inhibited by microtubule disruption, indicating that IRS-2 requires the microtubule cytoskeleton at the level of downstream effector activation. IRS-2 colocalization with tubulin is enhanced upon Taxol-mediated microtubule stabilization, which, together with the signaling data, suggests that the microtubule cytoskeleton may facilitate access of IRS-2 to downstream effectors such as AKT. Of clinical relevance is that our data reveal that expression of IRS-2 sensitizes breast carcinoma cells to apoptosis in response to treatment with microtubule-disrupting drugs, identifying IRS-2 as a potential biomarker for the response of breast cancer patients to Vinca alkaloid drug treatment.
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Affiliation(s)
- Jose Mercado-Matos
- From the Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Jennifer L Clark
- From the Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Andrew J Piper
- From the Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Jenny Janusis
- From the Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Leslie M Shaw
- From the Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
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12
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Luo J, Wen Q, Li J, Xu L, Chu S, Wang W, Shi L, Xie G, Huang D, Fan S. Increased expression of IRS-1 is associated with lymph node metastasis in nasopharyngeal carcinoma. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2014; 7:6117-6124. [PMID: 25337259 PMCID: PMC4203230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/20/2014] [Indexed: 06/04/2023]
Abstract
Nasopharyngeal carcinoma (NPC) is a head and neck malignant tumor rare throughout most of the world but common in Southeast Asia, especially in Southern China, which is with characteristics of early cervical lymph node metastasis and high incidence rate of distant metastasis. Insulin receptor substrate 1 (IRS-1) is a signaling adapter protein that is encoded by the IRS-1 gene in humans, plays an important role in the development, progression, invasion and metastasis of tumors. The aim of the present study was to investigate the association between the expression of IRS-1 protein and clinicopathological characteristics in NPC by immunohistochemistry. The results showed that the expression level of IRS-1 was significant higher in NPC than that in the control nasopharyngeal epithelia (P = 0.042). The positive percentage of IRS-1 expression in NPC with lymph node metastasis was also significantly higher than those without lymph node metastasis (P = 0.008). Positive expression of IRS-1 was proved to be the independent predicted factor for lymph node metastasis of NPC (P = 0.025) regardless of age, gender, histological type and clinical stages by multivariate logistic regression analysis. In addition, results showed higher sensitivity and agreement rate of IRS-1 for predicting lymph node metastasis of NPC patients. Taken together, high expression of IRS-1 might be closely correlated with lymph node metastasis in NPC and positive expression of IRS-1 could be used as an independent biomarker for predicting lymph node metastasis of NPC.
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Affiliation(s)
- Jiadi Luo
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Qiuyuan Wen
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Jiao Li
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Lina Xu
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Shuzhou Chu
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Weiyuan Wang
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Lei Shi
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Guiyuan Xie
- Department of Oncology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Donghai Huang
- Department of Otorhinolaryngology, Xiangya Hospital, Central South UniversityChangsha, Hunan, China
| | - Songqing Fan
- Department of Pathology, The Second Xiangya Hospital, Central South UniversityChangsha, Hunan, China
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Contaldo C, Myers TJ, Zucchini C, Manara MC, Chiodoni C, Colombo MP, Nicoletti G, Lollini PL, Li T, Longobardi L, Scotlandi K, Spagnoli A. Expression levels of insulin receptor substrate-1 modulate the osteoblastic differentiation of mesenchymal stem cells and osteosarcoma cells. Growth Factors 2014; 32:41-52. [PMID: 24438070 DOI: 10.3109/08977194.2013.870168] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The insulin-like growth factor-1 system, including its critical mediator insulin receptor substrate-1 (IRS-1), is involved in regulating osteosarcoma (OS) cell proliferation or differentiation. The aim of this study is to define the role of IRS-1 in OS cells by assessing the contribution of IRS-1 in the differentiation of human and murine OS cell lines and mouse mesenchymal stem cells (MSCs) and found that the basal level of IRS-1 is important for the initiation of differentiation. Both down-regulation and over-expression of IRS-1 inhibited osteoblastic differentiation. In vivo studies showed that OS cells over-expressing IRS-1 have increased metastatic potential and tumor growth. The proteasome inhibitor MG-132 led to an increase in IRS-1 protein level that inhibited osteoblastic differentiation, suggesting a role for proteasomal regulation in maintaining the appropriate expression level of IRS-1. Thus, precise regulation of IRS-1 expression level is critical for determining the differentiating capacity of MSCs and OS cells, and that derangement of IRS-1 levels can be a critical step in OS transformation.
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Affiliation(s)
- Clara Contaldo
- Laboratory of Experimental Oncology, CRS Development of Molecular Therapies, Orthopaedic Rizzoli Institute , Bologna , Italy
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Gao D, Li S. Biological resonance for cancer metastasis, a new hypothesis based on comparisons between primary cancers and metastases. CANCER MICROENVIRONMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL CANCER MICROENVIRONMENT SOCIETY 2013; 6:213-30. [PMID: 24214411 PMCID: PMC3855372 DOI: 10.1007/s12307-013-0138-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 10/22/2013] [Indexed: 12/11/2022]
Abstract
Many hypotheses have been proposed to try to explain cancer metastasis. However, they seem to be contradictory and have some limitations. Comparisons of primary tumors and matched metastases provide new insight into metastasis. The results show high concordances and minor differences at multiple scales from organic level to molecular level. The concordances reflect the commonality between primary cancer and metastasis, and also mean that metastatic cancer cells derived from primary cancer are quite conservative in distant sites. The differences reflect variation that cancer cells must acquire new traits to adapt to foreign milieu during the course of evolving into a new tumor in second organs. These comparisons also provided new information on understanding mechanism of vascular metastasis, organ-specific metastasis, and tumor dormancy. The collective results suggest a new hypothesis, biological resonance (bio-resonance) model. The hypothesis has two aspects. One is that primary cancer and matched metastasis have a common progenitor. The other is that both ancestors of primary cancer cells and metastatic cancer cells are under similar microenvironments and receive similar or same signals. When their interactions reach a status similar to primary cancer, metastasis will occur. Compared with previous hypotheses, the bio-resonance hypothesis seems to be more applicable for cancer metastasis to explain how, when and where metastasis occurs. Thus, it has important implications for individual prediction, prevention and treatment of cancer metastasis.
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Affiliation(s)
- Dongwei Gao
- 536 Hospital of PLA, 29# Xiadu street, Xining, 810007, Qinghai Province, People's Republic of China,
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15
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IRS1 is highly expressed in localized breast tumors and regulates the sensitivity of breast cancer cells to chemotherapy, while IRS2 is highly expressed in invasive breast tumors. Cancer Lett 2013; 338:239-48. [PMID: 23562473 DOI: 10.1016/j.canlet.2013.03.030] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 02/14/2013] [Accepted: 03/26/2013] [Indexed: 12/31/2022]
Abstract
Insulin receptor substrate (IRS) proteins have been shown to play an important role in breast cancer by differentially regulating cancer cell survival, proliferation, and motility. Furthermore, the IL-4-induced tyrosine phosphorylation of the transcription factor STAT6 was shown to protect breast cancer cells from apoptosis. Here, we analyzed human breast cancer tissues for the expression of IRS1, IRS2, STAT6, and tyrosine phosphorylated STAT6 (pSTAT6). We found that IRS1 and pSTAT6 were both highly expressed in ductal carcinoma in situ (DCIS). On the other hand, IRS2 expression was low in DCIS, but increased significantly in relation to tumor invasiveness. We utilized cell lines with disparate IRS1 expression, MDA-MB-231, MCF7, and MCF7 cells with depleted IRS1 due to shRNA lentiviral infection, to examine the role of IRS1 and IRS2 in the responsiveness of breast cancer cells to chemotherapy. We report that high IRS1 sensitized MCF7 cells to specific chemotherapeutic agents. These results suggest that high IRS1 with low IRS2 expression may predict the effectiveness of specific types of chemotherapy in breast cancer.
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16
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Chan SH, Kikkawa U, Matsuzaki H, Chen JH, Chang WC. Insulin receptor substrate-1 prevents autophagy-dependent cell death caused by oxidative stress in mouse NIH/3T3 cells. J Biomed Sci 2012; 19:64. [PMID: 22788551 PMCID: PMC3430578 DOI: 10.1186/1423-0127-19-64] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Accepted: 06/27/2012] [Indexed: 11/10/2022] Open
Abstract
Background Insulin receptor substrate (IRS)-1 is associated with tumorigenesis; its levels are elevated in several human cancers. IRS-1 protein binds to several oncogene proteins. Oxidative stress and reactive oxygen species (ROS) are involved in the initiation and progression of cancers. Cancer cells produce greater levels of ROS than normal cells do because of increased metabolic stresses. However, excessive production of ROS kills cancer cells. Autophagy usually serves as a survival mechanism in response to stress conditions, but excessive induction of autophagy results in cell death. In addition to inducing necrosis and apoptosis, ROS induces autophagic cell death. ROS inactivates IRS-1 mediated signaling and reduces intracellular IRS-1 concentrations. Thus, there is a complex relationship between IRS-1, ROS, autophagy, and cancer. It is not fully understood how cancer cells grow rapidly and survive in the presence of high ROS levels. Methods and results In this study, we established mouse NIH/3T3 cells that overexpressed IRS-1, so mimicking cancers with increased IRS-1 expression levels; we found that the IRS-1 overexpressing cells grow more rapidly than control cells do. Treatment of cells with glucose oxidase (GO) provided a continuous source of ROS; low dosages of GO promoted cell growth, while high doses induced cell death. Evidence for GO induced autophagy includes increased levels of isoform B-II microtubule-associated protein 1 light chain 3 (LC3), aggregation of green fluorescence protein-tagged LC3, and increased numbers of autophagic vacuoles in cells. Overexpression of IRS-1 resulted in inhibition of basal autophagy, and reduced oxidative stress-induced autophagy and cell death. ROS decreased the mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase signaling, while overexpression of IRS-1 attenuated this inhibition. Knockdown of autophagy-related gene 5 inhibited basal autophagy and diminished oxidative stress-induced autophagy and cell death. Conclusion Our results suggest that overexpression of IRS-1 promotes cells growth, inhibits basal autophagy, reduces oxidative stress-induced autophagy, and diminishes oxidative stress-mediated autophagy-dependent cell death. ROS-mediated autophagy may occur via inhibition of IRS-1/phosphatidylinositol 3-kinase/mTOR signaling. Our data afford a plausible explanation for IRS-1 involvement in tumor initiation and progression.
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Affiliation(s)
- Shih-Hung Chan
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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17
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Luo X, Fan S, Huang W, Zhai S, Ma Z, Li P, Sun SY, Wang X. Downregulation of IRS-1 promotes metastasis of head and neck squamous cell carcinoma. Oncol Rep 2012; 28:659-67. [PMID: 22664743 DOI: 10.3892/or.2012.1846] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 05/04/2012] [Indexed: 11/06/2022] Open
Abstract
Lymph node metastasis is responsible for the high morbidity of head and neck squamous cell carcinoma (HNSCC). To date, the role of insulin receptor substrate 1 (IRS-1) in tumorigenesis and metastasis of head and neck cancer has not been elucidated. In this study, we found a negative correlation of IRS-1 expression with tumor metastasis both in human tissue samples and in cell lines. Furthermore, we found that knockdown of IRS-1 expression enhanced cell invasive potency and induced EMT in parallel with upregulation of miR-9 expression. We propose that IRS-1 suppresses metastasis of head and neck cancer possibly through miR-9.
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Affiliation(s)
- Xuan Luo
- Department of Pharmacology, Nanjing Medical University, and Department of Pathology, Nanjing First Hospital, Nanjing, Jiangsu, PR China
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18
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Wang Y, Hua S, Tian W, Zhang L, Zhao J, Zhang H, Zhang W, Xue F. Mitogenic and anti-apoptotic effects of insulin in endometrial cancer are phosphatidylinositol 3-kinase/Akt dependent. Gynecol Oncol 2012; 125:734-41. [PMID: 22426488 DOI: 10.1016/j.ygyno.2012.03.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 03/07/2012] [Accepted: 03/08/2012] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To determine serum insulin levels, expression and phosphorylation of InsR, IRS-1 and Akt in endometrial cancer (EC) tissues, and to explore the correlation between them. To investigate if insulin-induced mitogenic and anti-apoptotic effects are PI3K-dependent in EC cells. METHODS Serum insulin levels were measured by radioimmunoassay. We performed RT-PCR and western blotting to evaluate the expression and activation of key proteins of PI3K/Akt pathway in 63 EC tissues. The proliferation and apoptosis rates were determined with MTT, BrdU and annexin V/PI assays. RESULTS Serum insulin levels and InsR, IRS-1 and Akt expression and phosphorylation were significantly elevated in patients with EC compared to those without EC. Additionally, levels of p-InsR, p-IRS-1, and p-Akt were significantly higher in patients with high-grade, advanced stage, deep myometrial invasion, and lymph-node metastasis. The expression and activation of InsR, IRS-1, and p-Akt were positively related with the levels of serum insulin. The insulin-induced mitogenic and anti-apoptotic effects in EC cells were blocked when cells were pre-incubated with LY294002. Ishikawa 3-H-12 cells showed increased p-Akt levels after treatment with insulin at 10(-8)M for 15min. The insulin-induced Akt activation was inhibited by LY294002 in a dose-dependent manner. CONCLUSION Insulin played an essential role in EC tumorigenesis. Activation of InsR, IRS-1, and Akt was associated with features of aggressive EC. Insulin was a mitogenic and anti-apoptotic agent for EC cells, and these effects were dependent on PI3K/Akt pathway. Decreasing insulin level and blocking the InsR-IRS-PI3K-Akt pathway could be viable preventive and therapeutic strategies for EC.
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Affiliation(s)
- Yingmei Wang
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
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19
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Clark JL, Dresser K, Hsieh CC, Sabel M, Kleer CG, Khan A, Shaw LM. Membrane localization of insulin receptor substrate-2 (IRS-2) is associated with decreased overall survival in breast cancer. Breast Cancer Res Treat 2011; 130:759-72. [PMID: 21258861 DOI: 10.1007/s10549-011-1353-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 01/10/2011] [Indexed: 12/15/2022]
Abstract
Recent studies have identified a role for insulin receptor substrate-2 (IRS-2) in promoting motility and metastasis in breast cancer. However, no published studies to date have examined IRS-2 expression in human breast tumors. We examined IRS-2 expression by immunohistochemistry (IHC) in normal breast tissue, benign breast lesions, and malignant breast tumors from the institutional pathology archives and a tumor microarray from a separate institution. Three distinct IRS-2 staining patterns were noted: diffusely cytoplasmic, punctate cytoplasmic, and localized to the cell membrane. The individual and pooled datasets were analyzed for associations of IRS-2 staining pattern with core clinical parameters and clinical outcomes. Univariate analysis revealed a trend toward decreased overall survival (OS) with IRS-2 membrane staining, and this association became significant upon multivariate analysis (P = 0.01). In progesterone receptor negative (PR-) tumors, in particular, IRS-2 staining at the membrane correlated with significantly worse OS than other IRS-2 staining patterns (P < 0.001). When PR status and IRS-2 staining pattern were evaluated in combination, PR- tumors with IRS-2 at the membrane were associated with a significantly decreased OS when compared with all other combinations (P = 0.002). Evaluation of IRS-2 staining patterns could potentially be used to identify patients with PR- tumors who would most benefit from aggressive treatment.
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Affiliation(s)
- Jennifer L Clark
- Department of Cancer Biology, University of Massachusetts Medical School, 364 Plantation St., Worcester, MA 01605, USA
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20
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Kanczuga-Koda L, Koda M, Tomaszewski J, Jarzabek K, Lotowska J, Baltaziak M, Sulkowska U, Sobaniec-Lotowska M, Sulkowski S. ERα and ERβ expression in correlation with Ki-67, Bcl-2 and Bak in primary tumors and lymph node metastases of breast cancer: The effect of pre-operative chemotherapy. Oncol Lett 2010; 1:1067-1071. [PMID: 22870114 DOI: 10.3892/ol.2010.178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Accepted: 09/02/2010] [Indexed: 11/06/2022] Open
Abstract
This study aimed to assess the pre-operative chemotherapy impact on the relationship between estrogen receptor (ER) expression and markers of proliferation and apoptosis in primary and metastatic breast cancer. Immunohistochemical examinations were conducted on surgically removed ductal invasive breast cancers and their lymph node metastases in 135 patients. A total of 64 patients from this group underwent pre-operative chemotherapy and in 71 cases the surgery was performed without primary chemotherapy. A negative correlation between ERα and Ki-67 was found in primary tumors and lymph node metastases. A positive correlation was observed between ERα and Bcl-2. A positive correlation was also noted between ERβ and Bak, suggesting that the two ERs were involved in the regulation of proteins responsible for the control of the apoptotic process. Assessment of the expression of the proteins conducted separately in primary tumors and lymph node metastases did not reveal a significant effect of pre-operative chemotherapy on the correlations of ERs with Ki-67, Bcl-2 and Bak. However, the analysis of the correlations between the receptor expression in primary tumors and Ki-67, Bcl-2 and Bak in lymph node metastases showed a statistically significant impact of pre-operative chemotherapy on the correlations of ERα and Bcl-2 with ERβ and Bak, confirming involvement of the two ERs in the regulation of apoptosis during breast carcinogenesis.
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Affiliation(s)
- Luiza Kanczuga-Koda
- Department of Pathology, Maria Sklodowska-Curie Memorial Bialystok Oncology Center, 15-027 Bialystok
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21
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Migliaccio I, Wu MF, Gutierrez C, Malorni L, Mohsin SK, Allred DC, Hilsenbeck SG, Osborne CK, Weiss H, Lee AV. Nuclear IRS-1 predicts tamoxifen response in patients with early breast cancer. Breast Cancer Res Treat 2009; 123:651-60. [PMID: 19924529 DOI: 10.1007/s10549-009-0632-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Accepted: 10/31/2009] [Indexed: 12/18/2022]
Abstract
Insulin receptor substrate-1 (IRS-1) is a cytoplasmic scaffolding protein that is phosphorylated by insulin-like growth factor-I receptor and recruits downstream effectors. Recent evidence suggests that IRS-1 has a nuclear localization and function. Here we investigated whether nuclear and cytoplasmic IRS-1 levels are associated with clinico-pathological characteristics and clinical outcome in breast cancer patients. Tissue microarrays from 1,097 patients with stage I-II breast cancer were stained by immunohistochemistry for IRS-1. Nuclear and cytoplasmic IRS-1 were scored separately according to the Allred score. Nuclear IRS-1 showed a positive association with estrogen receptor (ER) (r = 0.09, P = 0.003) and progesterone receptor (PR) (r = 0.08, P = 0.008) status and a negative correlation with lymph node involvement (r = -0.10, P = 0.001). Cytoplasmic IRS-1 did not correlate with ER or PR but showed a positive correlation with tumor size (r = 0.10, P = 0.001) and S-phase fraction (r = 0.16, P < 0.001). In univariate analysis, tamoxifen-treated patients with tumors showing positive nuclear IRS-1 had a better recurrence-free survival (RFS) (P = 0.009) and overall survival (OS) (P = 0.0007), while no association was shown between cytoplasmic IRS-1 and RFS or OS in the same group of patients. In multivariate analysis of patients receiving tamoxifen, negative nuclear IRS-1 showed a significantly reduced RFS (P = 0.046) and OS (P = 0.018). Combining both PR and nuclear IRS-1, tamoxifen-treated patients with PR+/IRS-1+ tumors had a better RFS (P = 0.0003) and OS (P < 0.0001) when compared with patients with PR-/IRS-1- tumors. In conclusion, nuclear IRS-1 may be a useful marker to predict tamoxifen response in patients with early breast cancer, particularly when assessed in combination with PR.
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Affiliation(s)
- Ilenia Migliaccio
- Lester and Sue Smith Breast Center, Baylor College of Medicine, One Baylor Plaza, BCM:600, Room N1110, Houston, TX 77030, USA
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22
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Mardilovich K, Pankratz SL, Shaw LM. Expression and function of the insulin receptor substrate proteins in cancer. Cell Commun Signal 2009; 7:14. [PMID: 19534786 PMCID: PMC2709114 DOI: 10.1186/1478-811x-7-14] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2009] [Accepted: 06/17/2009] [Indexed: 12/13/2022] Open
Abstract
The Insulin Receptor Substrate (IRS) proteins are cytoplasmic adaptor proteins that function as essential signaling intermediates downstream of activated cell surface receptors, many of which have been implicated in cancer. The IRS proteins do not contain any intrinsic kinase activity, but rather serve as scaffolds to organize signaling complexes and initiate intracellular signaling pathways. As common intermediates of multiple receptors that can influence tumor progression, the IRS proteins are positioned to play a pivotal role in regulating the response of tumor cells to many different microenvironmental stimuli. Limited studies on IRS expression in human tumors and studies on IRS function in human tumor cell lines and in mouse models have provided clues to the potential function of these adaptor proteins in human cancer. A general theme arises from these studies; IRS-1 and IRS-4 are most often associated with tumor growth and proliferation and IRS-2 is most often associated with tumor motility and invasion. In this review, we discuss the mechanisms by which IRS expression and function are regulated and how the IRS proteins contribute to tumor initiation and progression.
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Affiliation(s)
- Katerina Mardilovich
- Department of Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
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23
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Mukohara T, Shimada H, Ogasawara N, Wanikawa R, Shimomura M, Nakatsura T, Ishii G, Park JO, Jänne PA, Saijo N, Minami H. Sensitivity of breast cancer cell lines to the novel insulin-like growth factor-1 receptor (IGF-1R) inhibitor NVP-AEW541 is dependent on the level of IRS-1 expression. Cancer Lett 2009; 282:14-24. [PMID: 19345478 DOI: 10.1016/j.canlet.2009.02.056] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Revised: 11/27/2008] [Accepted: 02/25/2009] [Indexed: 11/15/2022]
Abstract
To investigate the potential value of targeting insulin-like growth factor-1 receptor (IGF-1R) in breast cancer, we examined the effects of NVP-AEW541, a selective small-molecule inhibitor of the IGF-1R tyrosine kinase, in a panel of 16 breast cancer cell lines. All cell lines expressed IGF-1R, but MCF-7 expressed much higher levels of insulin receptor substrate-1 (IRS-1) than the others. NVP-AEW541 was more potent at inhibiting growth of MCF-7 cells as compared to the others (IC(50), 1 microM vs. approximately 7 microM). Comparing MCF-7 to T47D cells, which express IGF-1R at a level identical to MCF-7 but have less than 1/30 the amount of IRS-1, NVP-AEW541 caused cell-cycle arrest at the G1-S boundary, reduced in vitro cell migration, and enhanced the cytotoxic effects of vinorelbine and paclitaxel in MCF-7, but not in T47D. While NVP-AEW541 decreased the phosphorylation of IGF-1R in both cell lines, it inhibited phosphorylation of Akt and disrupted the IRS-1/PI3K complex only in MCF-7. These findings suggest that inhibiting IGF-1R may be an effective therapeutic strategy for breast cancers that co-express IGF-1R and IRS-1 at high levels.
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Affiliation(s)
- Toru Mukohara
- Division of Oncology and Hematology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Japan.
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Gray SG, Al-Sarraf N, Baird AM, Gately K, McGovern E, O'Byrne KJ. Transcriptional regulation of IRS5/DOK4 expression in non-small-cell lung cancer cells. Clin Lung Cancer 2009; 9:367-74. [PMID: 19073520 DOI: 10.3816/clc.2008.n.053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The insulin-receptor substrate family plays important roles in cellular growth, signaling, and survival. Two new members of this family have recently been isolated: IRS5/Dok4 and IRS6/Dok5. This study examines the expression of IRS5/DOK4 in a panel of lung cancer cell lines and tumor specimens. The results demonstrate that expression of IRS5/DOK4 is frequently altered with both elevated and decreased expression in non-small-cell lung cancer (NSCLC) tumor specimens. The altered expression of IRS5/DOK4 observed in tumor samples is not due to aberrant methylation. In vitro cell culture studies demonstrate that treatment of NSCLC cell lines with the histone deacetylase inhibitor trichostatin A (TSA) upregulates IRS5/DOK4. This finding indicates that expression is regulated epigenetically at the level of chromatin remodeling. Chromatin immunoprecipitation experiments confirm that the IRS5/DOK4 promoter has enhanced histone hyperacetylation following treatments with TSA. Finally, hypoxia was demonstrated to downregulate IRS5/DOK4 expression. This expression was restored by TSA. The clinical relevance of altered IRS5/DOK4 expression in NSCLC requires further evaluation.
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Affiliation(s)
- Steven G Gray
- Department of Clinical Medicine, Thoracic Oncology Research Group, Institute of Molecular Medicine, Trinity Centre for Health Sciences, Dublin 8, Ireland
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25
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Chan BTY, Lee AV. Insulin receptor substrates (IRSs) and breast tumorigenesis. J Mammary Gland Biol Neoplasia 2008; 13:415-22. [PMID: 19030971 PMCID: PMC2819329 DOI: 10.1007/s10911-008-9101-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Accepted: 11/03/2008] [Indexed: 01/29/2023] Open
Abstract
Insulin receptor substrate (IRS)-1 and IRS-2 are adaptor proteins in the insulin-like growth factor I (IGF-I)/IGF-I receptor (IGF-IR) pathway that mediate cell proliferation, migration, and survival. In addition to their role as scaffolding proteins in the cytoplasm, they are able to translocate into the nucleus and regulate gene transcription. IRS levels are developmentally and hormonally regulated in the normal mammary gland and both are essential for normal mammary gland bud formation and lactation. Both IRS-1 and IRS-2 are transforming oncogenes, and induce transformation and metastasis in vitro and in vivo. In breast cancer IRSs have unique functions, with IRS-1 being mainly involved in cell proliferation and survival, whereas IRS-2 has clear roles in cell migration and metastasis. In this review we will discuss the roles of IRSs in mammary gland development and breast cancer.
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Affiliation(s)
- Bonita Tak-Yee Chan
- Lester and Sue Smith Breast Center, Department of Medicine and Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
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26
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Ramocki NM, Wilkins HR, Magness ST, Simmons JG, Scull BP, Lee GH, McNaughton KK, Lund PK. Insulin receptor substrate-1 deficiency promotes apoptosis in the putative intestinal crypt stem cell region, limits Apcmin/+ tumors, and regulates Sox9. Endocrinology 2008; 149:261-7. [PMID: 17916629 PMCID: PMC2194604 DOI: 10.1210/en.2007-0869] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Reduced apoptosis of crypt stem/progenitor cells and elevated insulin and IGFs are linked to colon cancer risk. Insulin receptor substrate-1 (IRS-1) mediates the actions of insulin, IGF-I, and IGF-II, but the role of endogenous IRS-1 in crypt apoptosis and cancer is undefined. Using IRS-1(-/-), IRS-1(+/-), and IRS-1(+/+) mice, we tested the hypothesis that reduced IRS-1 expression increases apoptosis of intestinal crypt cells and protects against Apc(min/+) (Min)/beta-catenin-driven intestinal tumors. Expression of Sox9, a transcriptional target of Tcf/beta-catenin and putative biomarker of crypt stem cells, was assessed in intestine of different IRS-1 genotypes and cell lines. Irradiation-induced apoptosis was significantly increased in the crypts and crypt stem cell region of IRS-1-deficient mice. Tumor load was significantly reduced by 31.2 +/- 14.6% in IRS-1(+/-)/Min and by 64.1 +/- 7.6% in IRS-1(-/-)/Min mice, with more prominent reductions in tumor number than size. Compared with IRS-1(+/+)/Min, IRS-1(-/-)/Min mice had fewer Sox9-positive cells in intestinal crypts and reduced Sox9 mRNA in intestine. IRS-1 overexpression increased Sox9 expression in an intestinal epithelial cell line. We conclude that even small reductions in endogenous IRS-1 increase apoptosis of crypt stem or progenitor cells, protect against beta-catenin-driven intestinal tumors, and reduce Sox9, a Tcf/beta-catenin target and putative stem/progenitor cell biomarker.
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Affiliation(s)
- Nicole M Ramocki
- Department of Cell and Molecular Physiology, University of North Carolina at Chapel Hill, North Carolina 27599-7545, USA. or
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Ravikumar S, Perez-Liz G, Del Vale L, Soprano DR, Soprano KJ. Insulin Receptor Substrate-1 Is an Important Mediator of Ovarian Cancer Cell Growth Suppression by All-trans Retinoic Acid. Cancer Res 2007; 67:9266-75. [PMID: 17909034 DOI: 10.1158/0008-5472.can-07-2088] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
There is a need to identify more effective drugs for the treatment of ovarian cancer as it is the leading cause of death among gynecologic tumors. All-trans retinoic acid (ATRA), a natural retinoid, arrests the growth of CA-OV3 ovarian carcinoma cells in G(0)-G(1). Because the insulin-like growth factor-I receptor has been implicated in the proliferation of various tumors, we investigated its potential role in the suppression of ovarian cancer cell growth by ATRA. Our studies revealed that insulin receptor substrate-1 (IRS-1) protein levels decrease in CA-OV3 cells on ATRA treatment, whereas no differences in IRS-1 levels were seen in the ATRA-resistant SK-OV3 cells. Moreover, CA-OV3 clones overexpressing IRS-1 were growth inhibited less by ATRA, whereas SK-OV3 clones in which levels of IRS-1 were reduced by expression of antisense IRS-1 became sensitive to growth inhibition by ATRA treatment. Studies to determine the mechanism by which ATRA reduced IRS-1 expression showed that ATRA altered steady-state levels of IRS-1 mRNA and the stability of IRS-1 protein. Finally, the role of IRS-1 as a potential molecular target of ATRA in ovarian tumors was assessed by immunohistochemistry in an ovarian cancer tissue array. Compared with normal ovary, the majority of malignant epithelial ovarian tumors overexpressed IRS-1. Thus, there seems to be a correlation between IRS-1 expression and malignancy in ovarian tumors. Our results suggest that IRS-1 is in fact an important growth-regulatory molecule that can be a potential effective target for chemotherapeutic intervention with growth-suppressive agents, including retinoids.
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Affiliation(s)
- Sharada Ravikumar
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA
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Liu TJ, LaFortune T, Honda T, Ohmori O, Hatakeyama S, Meyer T, Jackson D, de Groot J, Yung WKA. Inhibition of both focal adhesion kinase and insulin-like growth factor-I receptor kinase suppresses glioma proliferation in vitro and in vivo. Mol Cancer Ther 2007; 6:1357-67. [PMID: 17431114 DOI: 10.1158/1535-7163.mct-06-0476] [Citation(s) in RCA: 178] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Multiple genetic aberrations in human gliomas contribute to their highly infiltrative and rapid growth characteristics. Focal adhesion kinase (FAK) regulates tumor migration and invasion. Insulin-like growth factor-I receptor (IGF-IR), whose expression correlates with tumor grade, is involved in proliferation and survival. We hypothesized that inhibiting the phosphorylation of FAK and IGF-IR by NVP-TAE226 (hereafter called TAE226), a novel dual tyrosine kinase inhibitor of FAK and IGF-IR, would suppress the growth and invasion of glioma cells. In culture, TAE226 inhibited extracellular matrix-induced autophosphorylation of FAK (Tyr(397)). TAE226 also inhibited IGF-I-induced phosphorylation of IGF-IR and activity of its downstream target genes such as MAPK and Akt. TAE226 retarded tumor cell growth as assessed by a cell viability assay and attenuated G(2)-M cell cycle progression associated with a decrease in cyclin B1 and phosphorylated cdc2 (Tyr(15)) protein expression. TAE226 treatment inhibited tumor cell invasion by at least 50% compared with the control in an in vitro Matrigel invasion assay. Interestingly, TAE226 treatment of tumor cells containing wild-type p53 mainly exhibited G(2)-M arrest, whereas tumor cells bearing mutant p53 underwent apoptosis. Induction of apoptosis by TAE226 was substantiated by detection of caspase-3/7 activation and poly(ADP-ribose) polymerase cleavage and by an Annexin V apoptosis assay. More importantly, TAE226 treatment significantly increased the survival rate of animals in an intracranial glioma xenograft model. Collectively, these data show that blocking the signaling pathways of FAK and IGF-IR with TAE226 has the potential to be an efficacious treatment for human gliomas.
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Affiliation(s)
- Ta-Jen Liu
- Brain Tumor Center, Department of Neuro-Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.
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Ma Z, Gibson SL, Byrne MA, Zhang J, White MF, Shaw LM. Suppression of insulin receptor substrate 1 (IRS-1) promotes mammary tumor metastasis. Mol Cell Biol 2006; 26:9338-51. [PMID: 17030605 PMCID: PMC1698550 DOI: 10.1128/mcb.01032-06] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The insulin receptor substrate (IRS) proteins are cytoplasmic adaptors that organize signaling complexes downstream of activated cell surface receptors. Here, we show that IRS-1 and IRS-2, despite significant homology, play critical yet distinct functions in breast cancer, and we identify specific signaling pathways that are influenced by IRS-1 using the polyoma virus middle-T (PyV-MT) transgenic mouse model of mammary carcinoma and Irs-1 null (Irs1(-/-)) mice. The absence of Irs-1 expression enhanced metastatic spread significantly without a significant effect on primary tumor growth. Orthotopic transplant studies revealed that the increased metastatic potential of Irs1-deficient tumor cells is cell autonomous. Mammary tumors that developed in PyV-MT::Irs1(-/-) mice exhibited elevated Irs-2 function and enhanced phosphatidylinositol 3-kinase/Akt/mTor activity, suggesting that one mechanism by which Irs-1 impedes metastasis is to suppress Irs-2-dependent signaling. In support of this mechanism, reduction of Irs-2 expression in Irs1(-/-) tumor cells restored mTor signaling to wild-type levels. PyV-MT::Irs1(-/-) tumors also exhibited a significant increase in vascular endothelial growth factor expression and microvessel density, which could facilitate their dissemination. The significance of our findings for human breast cancer is heightened by our observation that Irs-1 is inactivated in wild-type, metastatic mammary tumors by serine phosphorylation. Collectively, our findings reveal that inactivation of IRS-1 enhances breast cancer metastasis and support the novel hypothesis that IRS-1 has metastasis suppressor functions for breast cancer.
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Affiliation(s)
- Zhefu Ma
- Department of Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
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30
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Dearth RK, Cui X, Kim HJ, Kuiatse I, Lawrence NA, Zhang X, Divisova J, Britton OL, Mohsin S, Allred DC, Hadsell DL, Lee AV. Mammary tumorigenesis and metastasis caused by overexpression of insulin receptor substrate 1 (IRS-1) or IRS-2. Mol Cell Biol 2006; 26:9302-14. [PMID: 17030631 PMCID: PMC1698542 DOI: 10.1128/mcb.00260-06] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Insulin receptor substrates (IRSs) are signaling adaptors that play a major role in the metabolic and mitogenic actions of insulin and insulin-like growth factors. Reports have recently noted increased levels, or activity, of IRSs in many human cancers, and some have linked this to poor patient prognosis. We found that overexpressed IRS-1 was constitutively phosphorylated in vitro and in vivo and that transgenic mice overexpressing IRS-1 or IRS-2 in the mammary gland showed progressive mammary hyperplasia, tumorigenesis, and metastasis. Tumors showed extensive squamous differentiation, a phenotype commonly seen with activation of the canonical beta-catenin signaling pathway. Consistent with this, IRSs were found to bind beta-catenin in vitro and in vivo. IRS-induced tumorigenesis is unique, given that the IRSs are signaling adaptors with no intrinsic kinase activity, and this supports a growing literature indicating a role for IRSs in cancer. This study defines IRSs as oncogene proteins in vivo and provides new models to develop inhibitors against IRSs for anticancer therapy.
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Affiliation(s)
- Robert K Dearth
- Breast Cancer, Baylor College of Medicine and Methodist Hospital, Department of Medicine, Houston, TX 77030, USA
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31
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Sisci D, Morelli C, Garofalo C, Romeo F, Morabito L, Casaburi F, Middea E, Cascio S, Brunelli E, Andò S, Surmacz E. Expression of nuclear insulin receptor substrate 1 in breast cancer. J Clin Pathol 2006; 60:633-41. [PMID: 16882697 PMCID: PMC1955087 DOI: 10.1136/jcp.2006.039107] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/metabolism
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Lobular/metabolism
- Carcinoma, Lobular/pathology
- Cell Nucleus/metabolism
- Cytoplasm/metabolism
- Estrogen Receptor alpha/metabolism
- Female
- Humans
- Immunoenzyme Techniques
- Insulin Receptor Substrate Proteins
- Mammary Glands, Human/metabolism
- Microscopy, Confocal
- Middle Aged
- Neoplasm Invasiveness
- Neoplasm Proteins/metabolism
- Phosphoproteins/metabolism
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Affiliation(s)
- Diego Sisci
- Department of Pharmaco-Biology, University of Calabria, Arcavacata di Rende, Italy
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32
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Cesarone G, Garofalo C, Abrams MT, Igoucheva O, Alexeev V, Yoon K, Surmacz E, Wickstrom E. RNAi-mediated silencing of insulin receptor substrate 1 (IRS-1) enhances tamoxifen-induced cell death in MCF-7 breast cancer cells. J Cell Biochem 2006; 98:440-50. [PMID: 16440325 DOI: 10.1002/jcb.20817] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Insulin receptor substrate 1 (IRS-1) is a major downstream signaling protein for insulin and insulin-like growth factor I (IGF-I) receptors, conveying signals to PI-3K/Akt and ERK1/2 pathways. In breast cancer, IRS-1 overexpression has been associated with tumor development, hormone-independence and antiestrogen-resistance. In part, these effects are related to potentiation of IRS-1/PI-3K/Akt signaling. In estrogen sensitive breast cancer cell lines, tamoxifen treatment reduces IRS-1 expression and function; consequently, inhibiting IRS-1/PI-3K signaling. We tested whether anti-IRS1 siRNA could inhibit growth and survival of estrogen-sensitive MCF-7 breast cancer cells, when used alone or in combination with TAM. Our results indicated: (a) out of four tested anti-IRS1 siRNAs, two siRNAs reduced IRS-1 protein by approximately three-fold in both growing and IGF-I-stimulated cells without affecting a closely related protein, IRS-2; (b) these effects paralleled IRS1 mRNA downregulation by approximately three-fold, measured by quantitative real time-polymerase chain reaction; (c) action of anti-IRS1 siRNAs induced the apoptotic response, observed by altered mitochondrial membrane potential coupled with downregulation of NF-kappaB target Bcl-xL and reduced cell viability; (d) anti-IRS1 siRNA treatment enhanced the cytotoxic effects of TAM by approximately 20%. In summary, anti-IRS1 RNAi strategy could become a potent tool to induce breast cancer cell death, especially if combined with standard TAM therapy.
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Affiliation(s)
- Gregory Cesarone
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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33
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Jones HE, Gee JM, Hutcheson IR, Nicholson RI. Insulin-like growth factor-I receptor signaling and resistance in breast cancer. Expert Rev Endocrinol Metab 2006; 1:33-46. [PMID: 30743767 DOI: 10.1586/17446651.1.1.33] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Insulin-like growth factor-I receptor (IGF-IR) signaling is involved in many fundamental adverse aspects of cancer cell biology, such as proliferation, cell survival and migration. Its anti-apoptotic properties have implicated the receptor in mediating decreased sensitivity to chemotherapeutic drugs and radiation treatment; however, data are emerging that also indicates a role for IGF-IR signaling in resistance, not only to antihormones but also to antigrowth factor strategies such as agents that target the erb family of receptors. As such, IGF-IR is clearly an attractive therapeutic target for the treatment of cancer, including breast cancer, where there is evidence of clinical prominence of the IGF-IR pathway and, as such, numerous strategies are currently in development to inhibit IGF-IR signaling. This review focuses on the ability of the IGF-IR to contribute to resistance mechanisms that support breast cancer cell growth in the presence of antihormones and antigrowth factors and discusses methods to maximize antitumor effects by combination regimens cotargeting the IGF-IR that may delay, or even prevent, progression to the resistant phenotype.
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Affiliation(s)
- Helen E Jones
- a Cardiff University, Tenovus Centre for Cancer Research, King Edward VII Avenue, Cardiff CF10 3XF, UK.
| | - Julia Mw Gee
- a Cardiff University, Tenovus Centre for Cancer Research, King Edward VII Avenue, Cardiff CF10 3XF, UK.
| | - Iain R Hutcheson
- a Cardiff University, Tenovus Centre for Cancer Research, King Edward VII Avenue, Cardiff CF10 3XF, UK.
| | - Robert I Nicholson
- a Cardiff University, Tenovus Centre for Cancer Research, King Edward VII Avenue, Cardiff CF10 3XF, UK.
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