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Markovics A, Lupo S, Patel N, Mikecz K, Sumner DR, Ross RD. SHP-1 Protein Tyrosine Phosphatase Affects Early Postnatal Bone Development in Mice. Calcif Tissue Int 2023; 112:472-482. [PMID: 36725700 DOI: 10.1007/s00223-023-01064-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 01/20/2023] [Indexed: 02/03/2023]
Abstract
The Src homology region 2 domain-containing phosphatase-1 (SHP-1) is an intracellular tyrosine phosphatase that plays a negative regulatory role in immune cell signaling. Absent or diminished SHP-1 catalytic activity results in reduced bone mass with enhanced bone resorption. Here, we sought to investigate if Shp1 overexpression leads to increased bone mass and improved mechanical properties. Male and female wildtype (WT) and SHP1-transgenic (Tg) mice at 28, 56, and 84 days of age were compared. We applied microcomputed tomography to assess femoral cortical bone geometry and trabecular architecture and 3-point mechanical bending to assess mid-diaphyseal structural and estimated material properties. Serum OPG, RANKL, P1NP, and CTX-1 concentrations were measured by enzyme-linked immunoassay. The majority of transgene effects were restricted to the 28-day-old mice. Trabecular bone volume per total volume, trabecular number, and connectivity density were greater in 28-day-old female SHP1-Tg mice when compared to WTs. SHP1-Tg female mice showed increased total and medullary areas, with no difference in cortical area and thickness. Cortical tissue mineral density was strongly genotype-dependent. Failure load, yield load, ultimate stress, and yield stress were all lower in 28-day-old SHP1-Tg females. In 28-day-old SHP1-Tg females, circulating levels of OPG and P1NP were higher and RANKL levels were lower than WT controls. Our study demonstrates a role for SHP-1 in early postnatal bone development; SHP-1 overexpression negatively impacted whole bone strength and material properties in females.
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Affiliation(s)
- Adrienn Markovics
- Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA.
| | - Sydney Lupo
- Department of Anatomy & Cell Biology, Rush University Medical Center, Chicago, IL, USA
| | - Niyati Patel
- Department of Anatomy & Cell Biology, Rush University Medical Center, Chicago, IL, USA
| | - Katalin Mikecz
- Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA
| | - D Rick Sumner
- Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA
- Department of Anatomy & Cell Biology, Rush University Medical Center, Chicago, IL, USA
- Rush Center for Integrated Microbiome and Chronobiology Research, Rush University Medical Center, Chicago, IL, USA
| | - Ryan D Ross
- Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA
- Department of Anatomy & Cell Biology, Rush University Medical Center, Chicago, IL, USA
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2
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Regulatory roles of MicroRNA in shaping T cell function, differentiation and polarization. Semin Cell Dev Biol 2021; 124:34-47. [PMID: 34446356 DOI: 10.1016/j.semcdb.2021.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 07/09/2021] [Accepted: 08/07/2021] [Indexed: 12/12/2022]
Abstract
T lymphocytes are an integral component of adaptive immunity with pleotropic effector functions. Impairment of T cell activity is implicated in various immune pathologies including autoimmune diseases, AIDS, carcinogenesis, and periodontitis. Evidently, T cell differentiation and function are under robust regulation by various endogenous factors that orchestrate underlying molecular pathways. MicroRNAs (miRNA) are a class of noncoding, regulatory RNAs that post-transcriptionally control multiple mRNA targets by sequence-specific interaction. In this article, we will review the recent progress in our understanding of miRNA-gene networks that are uniquely required by specific T cell effector functions and provide miRNA-mediated mechanisms that govern the fate of T cells. A subset of miRNAs may act in a synergistic or antagonistic manner to exert functional suppression of genes and regulate pathways that control T cell activation and differentiation. Significance of T cell-specific miRNAs and their dysregulation in immune-mediated diseases is discussed. Exosome-mediated horizontal transfer of miRNAs from antigen presenting cells (APCs) to T cells and from one T cell to another T cell subset and their impact on recipient cell functions is summarized.
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Markovics A, Toth DM, Glant TT, Mikecz K. Regulation of autoimmune arthritis by the SHP-1 tyrosine phosphatase. Arthritis Res Ther 2020; 22:160. [PMID: 32586377 PMCID: PMC7318740 DOI: 10.1186/s13075-020-02250-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 06/16/2020] [Indexed: 12/20/2022] Open
Abstract
Background The Src homology region 2 domain-containing phosphatase-1 (SHP-1) is known to exert negative regulatory effects on immune cell signaling. Mice with mutations in the Shp1 gene develop inflammatory skin disease and autoimmunity, but no arthritis. We sought to explore the role of SHP-1 in arthritis using an autoimmune mouse model of rheumatoid arthritis. We generated Shp1 transgenic (Shp1-Tg) mice to study the impact of SHP-1 overexpression on arthritis susceptibility and adaptive immune responses. Methods SHP-1 gene and protein expression as well as tyrosine phosphatase activity were evaluated in spleen cells of transgenic and wild type (WT) mice. WT and Shp1-Tg (homozygous or heterozygous for the transgene) mice were immunized with human cartilage proteoglycan (PG) in adjuvant, and arthritis symptoms were monitored. Protein tyrosine phosphorylation level, net cytokine secretion, and serum anti-human PG antibody titers were measured in immune cells from WT and Shp1-Tg mice. WT mice were treated with regorafenib orally to activate SHP-1 either before PG-induced arthritis (PGIA) symptoms developed (preventive treatment) or starting at an early stage of disease (therapeutic treatment). Data were statistically analyzed and graphs created using GraphPad Prism 8.0.2 software. Results SHP-1 expression and tyrosine phosphatase activity were elevated in both transgenic lines compared to WT mice. While all WT mice developed arthritis after immunization, none of the homozygous Shp1-Tg mice developed the disease. Heterozygous transgenic mice, which showed intermediate PGIA incidence, were selected for further investigation. We observed differences in interleukin-4 and interleukin-10 production in vitro, but serum anti-PG antibody levels were not different between the genotypes. We also found decreased tyrosine phosphorylation of several proteins of the JAK/STAT pathway in T cells from PG-immunized Shp1-Tg mice. Regorafenib administration to WT mice prevented the development of severe PGIA or reduced disease severity when started after disease onset. Conclusions Resistance to arthritis in the presence of SHP-1 overexpression likely results from the impairment of tyrosine phosphorylation (deactivation) of key immune cell signaling proteins in the JAK/STAT pathway, due to the overwhelming tyrosine phosphatase activity of the enzyme in Shp1-Tg mice. Our study is the first to investigate the role of SHP-1 in autoimmune arthritis using animals overexpressing this phosphatase. Pharmacological activation of SHP-1 might be considered as a new approach to the treatment of autoimmune arthritis.
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Affiliation(s)
- Adrienn Markovics
- Department of Orthopedic Surgery, Section of Molecular Medicine, Rush University Medical Center, 1735 W. Harrison Street, Cohn Research Building, Room 741, Chicago, IL, 60612, USA.
| | - Daniel M Toth
- Department of Orthopedic Surgery, Section of Molecular Medicine, Rush University Medical Center, 1735 W. Harrison Street, Cohn Research Building, Room 741, Chicago, IL, 60612, USA
| | - Tibor T Glant
- Department of Orthopedic Surgery, Section of Molecular Medicine, Rush University Medical Center, 1735 W. Harrison Street, Cohn Research Building, Room 741, Chicago, IL, 60612, USA
| | - Katalin Mikecz
- Department of Orthopedic Surgery, Section of Molecular Medicine, Rush University Medical Center, 1735 W. Harrison Street, Cohn Research Building, Room 741, Chicago, IL, 60612, USA
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Noguchi Y, Maeda A, Lo PC, Takakura C, Haneda T, Kodama T, Yoneyama T, Toyama C, Tazuke Y, Okuyama H, Miyagawa S. Human TIGIT on porcine aortic endothelial cells suppresses xenogeneic macrophage-mediated cytotoxicity. Immunobiology 2019; 224:605-613. [PMID: 31402149 DOI: 10.1016/j.imbio.2019.07.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/03/2019] [Accepted: 07/30/2019] [Indexed: 11/19/2022]
Abstract
PURPOSE The delayed rejection caused by strong cell-mediated innate and adaptive xenogeneic immune responses continues to be a major obstacle. Therefore, suppressing macrophage function could be effective in avoiding this type of rejection. In this study, the suppression of T-cell immunoglobulin and ITIM domain (TIGIT) function against macrophage-mediated xenogeneic rejection was investigated. MATERIAL AND METHODS Naïve porcine aortic endothelial cell (PAEC) and PAEC transfectant with TIGIT (PAEC/TIGIT) were co-cultured with M1 macrophages, and the degree of cytotoxicity was determined by a counting beads assay. The anti/pro-inflammatory gene expression was determined by RT-PCR and the phosphorylated SHP-1 in the macrophages after co-culturing with PAEC or PAEC/TIGIT was evaluated by western blotting. RESULTS CD155 was expressed at essentially equal levels on both M1 and M2 macrophages, whereas TIGIT was highly expressed on M2 macrophages but not in M1 macrophages. TIGIT on PAEC significantly reduced the cytotoxicity of M1 macrophages but no significant suppression of phagocytosis was detected. TIGIT also caused a decrease in the expression of pro-inflammatory cytokines, namely TNFα, IL-1β and IL-12 in M1 macrophages. Furthermore, PAEC/TIGIT caused a significant increase in phosphorylated SHP-1 in M1 macrophages compared to PAEC. CONCLUSION The findings of this study indicate that TIGIT suppresses xenogeneic M1 macrophage-induced cytotoxicity, probably at least in part, via the phosphorylation of SHP-1. In addition, the reduced expression of some pro-inflammatory cytokines, namely TNFα, IL-1β and IL-12, was observed in M1 macrophages that had been cultured with PAEC/TIGIT.
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Affiliation(s)
- Yuki Noguchi
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Akira Maeda
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
| | - Pei-Chi Lo
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Chihiro Takakura
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tomoko Haneda
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tasuku Kodama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tomohisa Yoneyama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Chiyoshi Toyama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yuko Tazuke
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hiroomi Okuyama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shuji Miyagawa
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Osaka, Japan; Meiji University International Institute for Bio-Resource Research, Kanagawa, Japan
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del Rio ML, Seebach JD, Fernández-Renedo C, Rodriguez-Barbosa JI. ITIM-dependent negative signaling pathways for the control of cell-mediated xenogeneic immune responses. Xenotransplantation 2013; 20:397-406. [PMID: 23968542 DOI: 10.1111/xen.12049] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 07/31/2013] [Indexed: 12/24/2022]
Abstract
Xenotransplantation is an innovative field of research with the potential to provide us with an alternative source of organs to face the severe shortage of human organ donors. For several reasons, pigs have been chosen as the most suitable source of organs and tissues for transplantation in humans. However, porcine xenografts undergo cellular immune responses representing a major barrier to their acceptance and normal functioning. Innate and adaptive xenogeneic immunity is mediated by both the recognition of xenogeneic tissue antigens and the lack of inhibition due to molecular cross-species incompatibilities of regulatory pathways. Therefore, the delivery of immunoreceptor tyrosine-based inhibitory motif (ITIM)-dependent and related negative signals to control innate (NK cells, macrophages) and adaptive T and B cells might overcome cell-mediated xenogeneic immunity. The proof of this concept has already been achieved in vitro by the transgenic overexpression of human ligands of several inhibitory receptors in porcine cells resulting in their resistance against xenoreactivity. Consequently, several transgenic pigs expressing tissue-specific human ligands of inhibitory coreceptors (HLA-E, CD47) or soluble competitors of costimulation (belatacept) have already been generated. The development of these robust and innovative approaches to modulate human anti-pig cellular immune responses, complementary to conventional immunosuppression, will help to achieve long-term xenograft survival. In this review, we will focus on the current strategies to enhance negative signaling pathways for the regulation of undesirable cell-mediated xenoreactive immune responses.
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Affiliation(s)
- Maria-Luisa del Rio
- Transplantation Immunobiology Section, Institute of Biomedicine, University of Leon, Leon, Spain; Leon University Hospital, Castilla and Leon Transplantation Regional Agency, Leon, Spain
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Liu SH, Wang KB, Lan KH, Lee WJ, Pan HC, Wu SM, Peng YC, Chen YC, Shen CC, Cheng HC, Liao KK, Sheu ML. Calpain/SHP-1 interaction by honokiol dampening peritoneal dissemination of gastric cancer in nu/nu mice. PLoS One 2012; 7:e43711. [PMID: 22937084 PMCID: PMC3427156 DOI: 10.1371/journal.pone.0043711] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 07/24/2012] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Honokiol, a small-molecular weight natural product, has previously been reported to activate apoptosis and inhibit gastric tumorigenesis. Whether honokiol inhibits the angiogenesis and metastasis of gastric cancer cells remains unknown. METHODOLOGY/PRINCIPAL FINDINGS We tested the effects of honokiol on angiogenic activity and peritoneal dissemination using in vivo, ex vivo and in vitro assay systems. The signaling responses in human gastric cancer cells, human umbilical vascular endothelial cells (HUVECs), and isolated tumors were detected and analyzed. In a xenograft gastric tumor mouse model, honokiol significantly inhibited the peritoneal dissemination detected by PET/CT technique. Honokiol also effectively attenuated the angiogenesis detected by chick chorioallantoic membrane assay, mouse matrigel plug assay, rat aortic ring endothelial cell sprouting assay, and endothelial cell tube formation assay. Furthermore, honokiol effectively enhanced signal transducer and activator of transcription (STAT-3) dephosphorylation and inhibited STAT-3 DNA binding activity in human gastric cancer cells and HUVECs, which was correlated with the up-regulation of the activity and protein expression of Src homology 2 (SH2)-containing tyrosine phosphatase-1 (SHP-1). Calpain-II inhibitor and siRNA transfection significantly reversed the honokiol-induced SHP-1 activity. The decreased STAT-3 phosphorylation and increased SHP-1 expression were also shown in isolated peritoneal metastatic tumors. Honokiol was also capable of inhibiting VEGF generation, which could be reversed by SHP-1 siRNA transfection. CONCLUSIONS/SIGNIFICANCE Honokiol increases expression and activity of SPH-1 that further deactivates STAT3 pathway. These findings also suggest that honokiol is a novel and potent inhibitor of angiogenesis and peritoneal dissemination of gastric cancer cells, providing support for the application potential of honokiol in gastric cancer therapy.
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Affiliation(s)
- Shing Hwa Liu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Keh Bin Wang
- Department of Nuclear Medicine, Kuang Tien General Hospital, Taichung, Taiwan
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Keng Hsin Lan
- Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wen Jane Lee
- Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Hung Chuan Pan
- Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Sheng Mao Wu
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Yen Chun Peng
- Division of Gastroenterology, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Yi Ching Chen
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Chin Chang Shen
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
- Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan
| | - Hsu Chen Cheng
- Department of life Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Ko Kaung Liao
- Department of Anatomy, Chung Shan Medical University, Taichung, Taiwan
| | - Meei Ling Sheu
- Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
- * E-mail:
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Yi T, Elson P, Mitsuhashi M, Jacobs B, Hollovary E, Budd TG, Spiro T, Triozzi P, Borden EC. Phosphatase inhibitor, sodium stibogluconate, in combination with interferon (IFN) alpha 2b: phase I trials to identify pharmacodynamic and clinical effects. Oncotarget 2012; 2:1155-64. [PMID: 22201704 DOI: 10.18632/oncotarget.393] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Since sodium stibogluconate (SSG) inhibited phosphatases including SHP-1 and augmented anti-tumor actions of IFN-α2b in vitro and in mice, two Phase I trials of SSG/IFN-α2b combination were undertaken to evaluate safety and target inhibition. Escalating doses of SSG (200-1200 mg/m2) and fixed doses of IFN-α2b (3x106 units/m2) with or without chemotherapy (dacarbazine, vinblastine, cisplatin) were evaluated for side effects and impact on SHP-1 phospho-substrates and IFNα-stimulated-genes (ISGs) in peripheral blood in 40 patients with metastatic melanoma, soft tissue sarcomas, gastrointestinal stromal tumors, and breast or colorectal carcinomas who did not have other established treatment options. Common adverse events were bone marrow suppression, fatigue, gastrointestinal upset, and asymptomatic lipase elevation (n=13); the latter was dose related and mostly after 10d of SSG/IFN-α2b in combination. Levels of SHP-1 substrates (pSTAT1, pSTAT3, pLck and pSlp76) were increased (up to 3x) in peripheral blood cells following SSG with no potentiation by combination with IFN-α2b. Representative ISGs in peripheral blood were induced after IFN-α2b at 4 and 24 hrs with selective modulations by combination. The median time on trials was 2.3 months (10-281d) with no objective regression of disease. Alive at 1y were 17/40 (43%) patients and after 2y were 8/40 (20%) following treatment initiation. These data demonstrate that SSG impacted signal molecules consistent with PTP inhibition and was tolerated in combination with IFN-α2b. Phase II investigations of SSG could safely utilize doses of up to 1200 mg/m2 of SSG for up to 10d alone or in combination with IFN-α2b with or without chemotherapy.
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Affiliation(s)
- Taolin Yi
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
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8
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Chiu YH, Mensah KA, Schwarz EM, Ju Y, Takahata M, Feng C, McMahon LA, Hicks DG, Panepento B, Keng PC, Ritchlin CT. Regulation of human osteoclast development by dendritic cell-specific transmembrane protein (DC-STAMP). J Bone Miner Res 2012; 27:79-92. [PMID: 21987375 PMCID: PMC3304467 DOI: 10.1002/jbmr.531] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2011] [Revised: 08/30/2011] [Accepted: 09/16/2011] [Indexed: 11/06/2022]
Abstract
Osteoclasts (OC) are bone-resorbing, multinucleated cells that are generated via fusion of OC precursors (OCP). The frequency of OCP is elevated in patients with erosive inflammatory arthritis and metabolic bone diseases. Although many cytokines and cell surface receptors are known to participate in osteoclastogenesis, the molecular mechanisms underlying the regulation of this cellular transformation are poorly understood. Herein, we focused our studies on the dendritic cell-specific transmembrane protein (DC-STAMP), a seven-pass transmembrane receptor-like protein known to be essential for cell-to-cell fusion during osteoclastogenesis. We identified an immunoreceptor tyrosine-based inhibitory motif (ITIM) in the cytoplasmic tail of DC-STAMP, and developed an anti-DC-STAMP monoclonal antibody 1A2 that detected DC-STAMP expression on human tumor giant cells, blocked OC formation in vitro, and distinguished four patterns of human PBMC with a positive correlation to OC potential. In freshly isolated monocytes, DC-STAMP(high) cells produced a higher number of OC in culture than DC-STAMP(low) cells and the surface expression of DC-STAMP gradually declined during osteoclastogenesis. Importantly, we showed that DC-STAMP is phosphorylated on its tyrosine residues and physically interacts with SHP-1 and CD16, an SH2-domain-containing tyrosine phosphatase and an ITAM-associated protein, respectively. Taken together, these data show that DC-STAMP is a potential OCP biomarker in inflammatory arthritis. Moreover, in addition to its effect on cell fusion, DC-STAMP dynamically regulates cell signaling during osteoclastogenesis.
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Affiliation(s)
- Ya-Hui Chiu
- Allergy/Immunology & Rheumatology Division, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA.
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9
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Yi T, Elson P, Mitsuhashi M, Jacobs B, Hollovary E, Budd GT, Spiro T, Triozzi P, Borden EC. Phosphatase inhibitor, sodium stibogluconate, in combination with interferon (IFN) alpha 2b: phase I trials to identify pharmacodynamic and clinical effects. Oncotarget 2011; 2:1155-1164. [PMID: 22201704 PMCID: PMC3282074 DOI: 10.18632/oncotarget.563] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 12/21/2011] [Indexed: 12/27/2022] Open
Abstract
Since sodium stibogluconate (SSG) inhibited phosphatases including SHP-1 and augmented anti-tumor actions of IFN-α2b in vitro and in mice, two Phase I trials of SSG/IFN-α2b combination were undertaken to evaluate safety and target inhibition. Escalating doses of SSG (200-1200 mg/m2) and fixed doses of IFN-α2b (3x106 units/m2) with or without chemotherapy (dacarbazine, vinblastine, cisplatin) were evaluated for side effects and impact on SHP-1 phospho-substrates and IFNα-stimulated-genes (ISGs) in peripheral blood in 40 patients with metastatic melanoma, soft tissue sarcomas, gastrointestinal stromal tumors, and breast or colorectal carcinomas who did not have other established treatment options. Common adverse events were bone marrow suppression, fatigue, gastrointestinal upset, and asymptomatic lipase elevation (n=13); the latter was dose related and mostly after 10d of SSG/IFN-α2b in combination. Levels of SHP-1 substrates (pSTAT1, pSTAT3, pLck and pSlp76) were increased (up to 3x) in peripheral blood cells following SSG with no potentiation by combination with IFN-α2b. Representative ISGs in peripheral blood were induced after IFN-α2b at 4 and 24 hrs with selective modulations by combination. The median time on trials was 2.3 months (10-281d) with no objective regression of disease. Alive at 1y were 17/40 (43%) patients and after 2y were 8/40 (20%) following treatment initiation. These data demonstrate that SSG impacted signal molecules consistent with PTP inhibition and was tolerated in combination with IFN-α2b. Phase II investigations of SSG could safely utilize doses of up to 1200 mg/m2 of SSG for up to 10d alone or in combination with IFN-α2b with or without chemotherapy.
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Affiliation(s)
- Taolin Yi
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
- Department of Immunology of Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, USA
| | - Paul Elson
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
| | | | - Barbara Jacobs
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
| | - Emese Hollovary
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
| | - G. Thomas Budd
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
| | - Timothy Spiro
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
| | - Pierre Triozzi
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
| | - Ernest C. Borden
- Taussig Cancer Institute, The Cleveland Clinic, Cleveland, OH, USA
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Pfirsch-Maisonnas S, Aloulou M, Xu T, Claver J, Kanamaru Y, Tiwari M, Launay P, Monteiro RC, Blank U. Inhibitory ITAM Signaling Traps Activating Receptors with the Phosphatase SHP-1 to Form Polarized "Inhibisome" Clusters. Sci Signal 2011; 4:ra24. [DOI: 10.1126/scisignal.2001309] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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11
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Peng Q, Malhotra S, Torchia JA, Kerr WG, Coggeshall KM, Humphrey MB. TREM2- and DAP12-dependent activation of PI3K requires DAP10 and is inhibited by SHIP1. Sci Signal 2010; 3:ra38. [PMID: 20484116 DOI: 10.1126/scisignal.2000500] [Citation(s) in RCA: 264] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The activation and fusion of macrophages and of osteoclasts require the adaptor molecule DNAX-activating protein of 12 kD (DAP12), which contains immunoreceptor tyrosine-based activation motifs (ITAMs). TREM2 (triggering receptor expressed on myeloid cells-2) is the main DAP12-associated receptor in osteoclasts and, similar to DAP12 deficiency, loss of TREM2 in humans leads to Nasu-Hakola disease, which is characterized by bone cysts and dementia. Furthermore, in vitro experiments have shown that deficiency in DAP12 or TREM2 leads to impaired osteoclast development and the formation of mononuclear osteoclasts. Here, we demonstrate that the ligation of TREM2 activated phosphatidylinositol 3-kinase (PI3K), extracellular signal-regulated kinase 1 (ERK1) and ERK2, and the guanine nucleotide exchange factor Vav3; induced the mobilization of intracellular calcium (Ca(2+)) and the reorganization of actin; and prevented apoptosis. The signaling adaptor molecule DAP10 played a key role in the TREM2- and DAP12-dependent recruitment of PI3K to the signaling complex. Src homology 2 (SH2) domain-containing inositol phosphatase-1 (SHIP1) inhibited TREM2- and DAP12-induced signaling by binding to DAP12 in an SH2 domain-dependent manner and preventing the recruitment of PI3K to DAP12. These results demonstrate a previously uncharacterized interaction of SHIP1 with DAP12 that functionally limits TREM2- and DAP12-dependent signaling and identify a mechanism through which SHIP1 regulates key ITAM-containing receptors by directly blocking the binding and activation of PI3K.
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Affiliation(s)
- Qisheng Peng
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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Smith K, Humphreys D, Hume PJ, Koronakis V. Enteropathogenic Escherichia coli Recruits the Cellular Inositol Phosphatase SHIP2 to Regulate Actin-Pedestal Formation. Cell Host Microbe 2010; 7:13-24. [DOI: 10.1016/j.chom.2009.12.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 10/28/2009] [Accepted: 12/01/2009] [Indexed: 12/11/2022]
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13
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Hawkins PT, Stephens LR, Suire S, Wilson M. PI3K signaling in neutrophils. Curr Top Microbiol Immunol 2010; 346:183-202. [PMID: 20473789 DOI: 10.1007/82_2010_40] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PI3Ks play important roles in the signaling pathways used by a wide variety of cell surface receptors on neutrophils. Class IB PI3K plays a major role in the initial generation of PtdIns(3,4,5)P₃ by Gi-coupled G-protein coupled receptors (GPCRs) (e.g., receptors for fMLP, C5a, LTB₄). Class IA PI3Ks generate PtdIns(3,4,5)P₃ downstream of receptors which directly or indirectly couple to protein tyrosine kinases such as integrins, FcγRs, cytokine receptors, and GPCRs. The PtdIns(3,4,5)P₃ made by Class I PI3Ks regulates the activity of several different effector proteins, many of which are plasma membrane GEFs or GAPs for small GTPases. Class III PI3K generates PtdIns(3)P in the phagosome membrane and plays an important role in efficient assembly of the NADPH oxidase at this location. Much still remains to be discovered about the molecular details that govern activation of PI3Ks and the mechanisms by which these enzymes regulate complex cellular processes, such as neutrophil spreading, chemotaxis, phagocytosis, and killing of pathogens. However, it is clear from recent use of transgenic mouse models and isoform-selective PI3K inhibitors that these pathways are important in regulating neutrophil recruitment to sites of infection and damage in vivo. Thus, PI3K pathways may present novel opportunities for selective inhibition in some inflammatory pathologies.
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Affiliation(s)
- Phillip T Hawkins
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK.
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14
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Blank U, Launay P, Benhamou M, Monteiro RC. Inhibitory ITAMs as novel regulators of immunity. Immunol Rev 2009; 232:59-71. [DOI: 10.1111/j.1600-065x.2009.00832.x] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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15
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Mori Y, Tsuji S, Inui M, Sakamoto Y, Endo S, Ito Y, Fujimura S, Koga T, Nakamura A, Takayanagi H, Itoi E, Takai T. Inhibitory Immunoglobulin-Like Receptors LILRB and PIR-B Negatively Regulate Osteoclast Development. THE JOURNAL OF IMMUNOLOGY 2008; 181:4742-51. [DOI: 10.4049/jimmunol.181.7.4742] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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16
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Abstract
Protein tyrosine phosphatases (PTPases) are attractive targets for developing novel cancer therapeutics. Activated via gain-of-function point mutations or overexpression, several PTPases have been identified as critical oncogenic molecules in human malignancies that may be targeted with small chemical inhibitors as a therapeutic strategy. Tumor suppressor PTPases have also been discovered as contributing factors in cancer development that may be targeted via intervention of downstream signaling events for therapeutic purposes. In addition, PTPases have been identified as key negative regulators of cytokines or immune cells. Targeting these negative PTPases may improve the efficacy of cytokine therapy and immunotherapy, which currently have modest response rates and limited survival benefit. Inhibitors of selective PTPases have demonstrated significant preclinical antitumor activity, leading to early-phase clinical trials. Further research and development could lead to PTPase-targeted cancer therapeutics in the near future.
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17
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Targeting DCIR on human plasmacytoid dendritic cells results in antigen presentation and inhibits IFN-alpha production. Blood 2008; 111:4245-53. [PMID: 18258799 DOI: 10.1182/blood-2007-03-081398] [Citation(s) in RCA: 200] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
C-type lectin receptors (CLRs) fulfill multiple functions within the immune system by recognition of carbohydrate moieties on foreign or (altered) self-structures. CLRs on myeloid dendritic cells (DCs) have been well characterized as pattern-recognition receptors (PRRs) combining ligand internalization with complex signaling events. Much less is known about CLR expression and function in human plasmacytoid DCs (pDCs), the major type I interferon (IFN) producers. In this study, we demonstrate that, next to the CLR BDCA-2, human pDCs express DC immunoreceptor (DCIR), a CLR with putative immune-inhibitory function, but not dectin-1, mannose receptor, or DC-specific ICAM-3-grabbing nonintegrin. DCIR surface levels are reduced on pDC maturation after TLR9 triggering. Interestingly, DCIR triggering inhibits TLR9-induced IFN-alpha production while leaving up-regulation of costimulatory molecule expression unaffected. Furthermore, DCIR is readily internalized into pDCs after receptor triggering. We show that DCIR internalization is clathrin-dependent because it can be inhibited by hypertonic shock and dominant-negative dynamin. Importantly, antigens targeted to pDCs via DCIR are presented to T cells. These findings indicate that targeting DCIR on pDCs not only results in efficient antigen presentation but also affects TLR9-induced IFN-alpha production. Collectively, the data show that targeting of DCIR can modulate human pDC function and may be applied in disease prevention and treatment.
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18
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Kono T, Imai Y, Yasuda SI, Ohmori K, Fukui H, Ichikawa K, Tomita S, Imura J, Kuroda Y, Ueda Y, Fujimori T. The CD155/poliovirus receptor enhances the proliferation of ras-mutated cells. Int J Cancer 2008; 122:317-24. [PMID: 17893876 DOI: 10.1002/ijc.23080] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Stimulation of the CD155/poliovirus receptor, which localizes in the cell-matrix and at cell-cell junctions, inhibits cell adhesion and enhances cell migration. Necl-5, a mouse homolog of CD155, is implicated in the formation of adherence junctions. Recently, Necl-5 has also been found to enhance cell proliferation via the stimulation of serum and platelet-derived growth factor through the Ras-Raf-MEK-ERK signaling pathway. In our present study, we find that CD155 significantly enhances the serum-induced cell proliferation of NIH3T3 cells which have been transformed by an oncogenic Ras (V12Ras-NIH3T3), but not the parental cells. CD155 expression in V12Ras-NIH3T3 cells is also found to upregulate cyclin D2, downregulate p27(Kip1) and shorten the G0/G1 phase of the cell cycle. An inhibitor of focal adhesion kinase does not reduce this CD155-mediated enhancement of V12Ras-NIH3T3 cell proliferation. The expression of CD155DeltaCP, which lacks the cytoplasmic region including the immunoreceptor tyrosine-based inhibitory motif (ITIM), has a reduced ability to enhance the serum responsiveness of V12Ras-NIH3T3 cells, suggesting that the ITIM might be required for this effect of CD155. In addition, the overexpression of exogenous CD155 enhances the serum responsiveness of HT1080 cells, which harbor a mutant N-ras gene. On the other hand, siRNA-induced knockdown of endogenous CD155 and/or CD155DeltaCP expression significantly repress the serum responsiveness of DLD-1 cells, which express endogenous CD155 and harbor a mutant K-ras gene, suggesting that this mutant may function in a dominant negative manner. Taken together, our present data suggest that CD155, at least in part, enhances the proliferation of ras-mutated cells.
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Affiliation(s)
- Tokuyuki Kono
- Department of Surgical and Molecular Pathology, Dokkyo Medical University School of Medicine, Tochigi, Japan
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19
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Ong CJ, Ming-Lum A, Nodwell M, Ghanipour A, Yang L, Williams DE, Kim J, Demirjian L, Qasimi P, Ruschmann J, Cao LP, Ma K, Chung SW, Duronio V, Andersen RJ, Krystal G, Mui ALF. Small-molecule agonists of SHIP1 inhibit the phosphoinositide 3-kinase pathway in hematopoietic cells. Blood 2007; 110:1942-9. [PMID: 17502453 DOI: 10.1182/blood-2007-03-079699] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Abstract
Because phosphoinositide 3-kinase (PI3K) plays a central role in cellular activation, proliferation, and survival, pharmacologic inhibitors targeting components of the PI3K pathway are actively being developed as therapeutics for the treatment of inflammatory disorders and cancer. These targeted drugs inhibit the activity of either PI3K itself or downstream protein kinases. However, a previously unexplored, alternate strategy is to activate the negative regulatory phosphatases in this pathway. The SH2-containing inositol-5′-phosphatase SHIP1 is a normal physiologic counter-regulator of PI3K in immune/hematopoietic cells that hydrolyzes the PI3K product phosphatidylinositiol-3,4,5-trisphosphate (PIP3). We now describe the identification and characterization of potent and specific small-molecule activators of SHIP1. These compounds represent the first small-molecule activators of a phosphatase, and are able to activate recombinant SHIP1 enzyme in vitro and stimulate SHIP1 activity in intact macrophage and mast cells. Mechanism of activation studies with these compounds suggest that they bind a previously undescribed, allosteric activation domain within SHIP1. Furthermore, in vivo administration of these compounds was protective in mouse models of endotoxemia and acute cutaneous anaphylaxis, suggesting that SHIP1 agonists could be used therapeutically to inhibit the PI3K pathway.
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Affiliation(s)
- Christopher J Ong
- Department of Surgery, University of British Columbia, Vancouver, Canda
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20
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Kamen LA, Levinsohn J, Swanson JA. Differential association of phosphatidylinositol 3-kinase, SHIP-1, and PTEN with forming phagosomes. Mol Biol Cell 2007; 18:2463-72. [PMID: 17442886 PMCID: PMC1924803 DOI: 10.1091/mbc.e07-01-0061] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
In macrophages, enzymes that synthesize or hydrolyze phosphatidylinositol (3,4,5)-trisphosphate [PI(3,4,5)P(3)] regulate Fcgamma receptor-mediated phagocytosis. Inhibition of phosphatidylinositol 3-kinase (PI3K) or overexpression of the lipid phosphatases phosphatase and tensin homologue (PTEN) and Src homology 2 domain-containing inositol phosphatase (SHIP-1), which hydrolyze PI(3,4,5)P(3) to phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 3,4-bisphosphate [PI(3,4)P(2)], respectively, inhibit phagocytosis in macrophages. To examine how these enzymes regulate phagosome formation, the distributions of yellow fluorescent protein (YFP) chimeras of enzymes and pleckstrin homology (PH) domains specific for their substrates and products were analyzed quantitatively. PTEN-YFP did not localize to phagosomes, suggesting that PTEN regulates phagocytosis globally within the macrophage. SHIP1-YFP and p85-YFP were recruited to forming phagosomes. SHIP1-YFP sequestered to the leading edge and dissociated from phagocytic cups earlier than did p85-cyan fluorescent protein, indicating that SHIP-1 inhibitory activities are restricted to the early stages of phagocytosis. PH domain chimeras indicated that early during phagocytosis, PI(3,4,5)P(3) was slightly more abundant than PI(3,4)P(2) at the leading edge of the forming cup. These results support a model in which phagosomal PI3K generates PI(3,4,5)P(3) necessary for later stages of phagocytosis, PTEN determines whether those late stages can occur, and SHIP-1 regulates when and where they occur by transiently suppressing PI(3,4,5)P(3)-dependent activities necessary for completion of phagocytosis.
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Affiliation(s)
- Lynn A. Kamen
- *Department of Microbiology and Immunology and
- Program in Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-0620
| | | | - Joel A. Swanson
- *Department of Microbiology and Immunology and
- Program in Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-0620
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21
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Yamashita Y, Phee H, Tudor KSRS, Rossi MID, Parnes JR, Coggeshall KM, Kincade PW. A unique CD72 epitope suggests a potential interaction with Fc gamma RII/CD32 on B lineage lymphocytes. Hybridoma (Larchmt) 2006; 25:107-14. [PMID: 16796456 DOI: 10.1089/hyb.2006.25.107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
It has long been known that ligation of the transmembrane CD72 glycoprotein delivers signals to B lymphocytes, with the outcome depending on context. Of particular interest is its ability to function as a counter-receptor/ ligand for the CD100 semaphorin protein. We have now obtained evidence that CD72 physically interacts on the lymphocyte membrane with Fcgamma receptor II (CD32). The association was first revealed with a new monoclonal antibody that recognizes polymorphic determinants on murine CD72. Although the specificity for CD72 was clear from immunoblotting, transfection and other experiments, staining with this reagent was inhibited when cells were pretreated with an Fc receptor-blocking antibody (CD16/CD32 specific). Furthermore, confocal microscopy revealed that the two molecules co-distributed on viable B cells. We also used the antibody to determine when CD72 becomes available to maturing lymphocytes. The marker is first acquired as large pre-B cells and enter the IL-7 independent phase of maturation within bone marrow. Subsequent interactions between CD72 and CD32 may cooperatively deliver negative signals that modulate humoral immune responses.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/immunology
- Antigens, CD/metabolism
- Antigens, Differentiation, B-Lymphocyte/genetics
- Antigens, Differentiation, B-Lymphocyte/immunology
- Antigens, Differentiation, B-Lymphocyte/metabolism
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- COS Cells
- Cell Line, Tumor
- Cell Lineage/immunology
- Chlorocebus aethiops
- Epitopes, B-Lymphocyte/immunology
- Epitopes, B-Lymphocyte/metabolism
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Rats
- Rats, Wistar
- Receptors, IgG/metabolism
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Affiliation(s)
- Yoshio Yamashita
- Immunobiology & Cancer Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
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22
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Ai J, Maturu A, Johnson W, Wang Y, Marsh CB, Tridandapani S. The inositol phosphatase SHIP-2 down-regulates FcgammaR-mediated phagocytosis in murine macrophages independently of SHIP-1. Blood 2005; 107:813-20. [PMID: 16179375 PMCID: PMC1895625 DOI: 10.1182/blood-2005-05-1841] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
FcgammaR-mediated phagocytosis of IgG-coated particles is a complex process involving the activation of multiple signaling enzymes and is regulated by the inositol phosphatases PTEN (phosphatase and tensin homolog deleted on chromosome 10) and SHIP-1 (Src homology [SH2] domain-containing inositol phosphatase). In a recent study we have demonstrated that SHIP-2, an inositol phosphatase with high-level homology to SHIP-1, is involved in FcgammaR signaling. However, it is not known whether SHIP-2 plays a role in modulating phagocytosis. In this study we have analyzed the role of SHIP-2 in FcgammaR-mediated phagocytosis using independent cell models that allow for manipulation of SHIP-2 function without influencing the highly homologous SHIP-1. We present evidence that SHIP-2 translocates to the site of phagocytosis and down-regulates FcgammaR-mediated phagocytosis. Our data indicate that SHIP-2 must contain both the N-terminal SH2 domain and the C-terminal proline-rich domain to mediate its inhibitory effect. The effect of SHIP-2 is independent of SHIP-1, as overexpression of dominant-negative SHIP-2 in SHIP-1-deficient primary macrophages resulted in enhanced phagocytic efficiency. Likewise, specific knockdown of SHIP-2 expression using siRNA resulted in enhanced phagocytosis. Finally, analysis of the molecular mechanism of SHIP-2 down-regulation of phagocytosis revealed that SHIP-2 down-regulates upstream activation of Rac. Thus, we conclude that SHIP-2 is a novel negative regulator of FcgammaR-mediated phagocytosis independent of SHIP-1.
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Affiliation(s)
- Jing Ai
- Molecular, Cellular, and Developmental Biology Program, The Ohio State University, USA
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23
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Ishikawa-Sekigami T, Kaneko Y, Okazawa H, Tomizawa T, Okajo J, Saito Y, Okuzawa C, Sugawara-Yokoo M, Nishiyama U, Ohnishi H, Matozaki T, Nojima Y. SHPS-1 promotes the survival of circulating erythrocytes through inhibition of phagocytosis by splenic macrophages. Blood 2005; 107:341-8. [PMID: 16141346 DOI: 10.1182/blood-2005-05-1896] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The lifespan of circulating red blood cells (RBCs) produced in bone marrow is determined by their elimination through phagocytosis by splenic macrophages. The mechanism by which RBC elimination is regulated has remained unclear, however. The surface glycoprotein SHPS-1, a member of the immunoglobulin superfamily, is abundant in macrophages. We have now examined the regulation of RBC turnover with the use of mice that express a mutant form of SHPS-1 lacking most of its cytoplasmic region. The mutant mice manifested mild anemia as well as splenomegaly characterized by expansion of the red pulp. The numbers of erythroid precursor cells in the spleen and of circulating reticulocytes were also increased in the mutant mice. In contrast, the half-life of circulating RBCs was reduced in these animals, and the rate of clearance of injected opsonized RBCs from the peripheral circulation was increased in association with their incorporation into splenic macrophages. Phagocytosis of opsonized RBCs by splenic macrophages from mutant mice in vitro was also increased compared with that observed with wild-type macrophages. These results suggest that SHPS-1 negatively regulates the phagocytosis of RBCs by splenic macrophages, thereby determining both the lifespan of individual RBCs and the number of circulating erythrocytes.
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Affiliation(s)
- Tomomi Ishikawa-Sekigami
- Department of Medicine and Clinical Scinece, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
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24
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Yu P, Constien R, Dear N, Katan M, Hanke P, Bunney TD, Kunder S, Quintanilla-Martinez L, Huffstadt U, Schröder A, Jones NP, Peters T, Fuchs H, de Angelis MH, Nehls M, Grosse J, Wabnitz P, Meyer TPH, Yasuda K, Schiemann M, Schneider-Fresenius C, Jagla W, Russ A, Popp A, Josephs M, Marquardt A, Laufs J, Schmittwolf C, Wagner H, Pfeffer K, Mudde GC. Autoimmunity and Inflammation Due to a Gain-of-Function Mutation in Phospholipase Cγ2 that Specifically Increases External Ca2+ Entry. Immunity 2005; 22:451-65. [PMID: 15845450 DOI: 10.1016/j.immuni.2005.01.018] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2004] [Revised: 01/07/2005] [Accepted: 01/12/2005] [Indexed: 01/16/2023]
Abstract
The identification of specific genetic loci that contribute to inflammatory and autoimmune diseases has proved difficult due to the contribution of multiple interacting genes, the inherent genetic heterogeneity present in human populations, and a lack of new mouse mutants. By using N-ethyl-N-nitrosourea (ENU) mutagenesis to discover new immune regulators, we identified a point mutation in the murine phospholipase Cg2 (Plcg2) gene that leads to severe spontaneous inflammation and autoimmunity. The disease is composed of an autoimmune component mediated by autoantibody immune complexes and B and T cell independent inflammation. The underlying mechanism is a gain-of-function mutation in Plcg2, which leads to hyperreactive external calcium entry in B cells and expansion of innate inflammatory cells. This mutant identifies Plcg2 as a key regulator in an autoimmune and inflammatory disease mediated by B cells and non-B, non-T haematopoietic cells and emphasizes that by distinct genetic modulation, a single point mutation can lead to a complex immunological phenotype.
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Affiliation(s)
- Philipp Yu
- Ingenium Pharmaceuticals AG, Fraunhoferstrasse 13, 82152 Martinsried, Munich, Germany.
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25
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Cherwinski HM, Murphy CA, Joyce BL, Bigler ME, Song YS, Zurawski SM, Moshrefi MM, Gorman DM, Miller KL, Zhang S, Sedgwick JD, Phillips JH. The CD200 receptor is a novel and potent regulator of murine and human mast cell function. THE JOURNAL OF IMMUNOLOGY 2005; 174:1348-56. [PMID: 15661892 DOI: 10.4049/jimmunol.174.3.1348] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CD200R is a member of the Ig supergene family that is primarily expressed on myeloid cells. Recent in vivo studies have suggested that CD200R is an inhibitory receptor capable of regulating the activation threshold of inflammatory immune responses. Here we provide definitive evidence that CD200R is expressed on mouse and human mast cells and that engagement of CD200R by agonist Abs or ligand results in a potent inhibition of mast cell degranulation and cytokine secretion responses. CD200R-mediated inhibition of FcepsilonRI activation was observed both in vitro and in vivo and did not require the coligation of CD200R to FcepsilonRI. Unlike the majority of myeloid inhibitory receptors, CD200R does not contain a phosphatase recruiting inhibitory motif (ITIM); therefore, we conclude that CD200R represents a novel and potent inhibitory receptor that can be targeted in vivo to regulate mast cell-dependent pathologies.
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MESH Headings
- Animals
- Antigens, CD
- Antigens, Surface/biosynthesis
- Antigens, Surface/immunology
- Antigens, Surface/metabolism
- Antigens, Surface/physiology
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Cell Degranulation/immunology
- Cells, Cultured
- Cytokines/antagonists & inhibitors
- Cytokines/metabolism
- Down-Regulation/immunology
- Fetal Blood/cytology
- Fetal Blood/immunology
- Fetal Blood/metabolism
- Humans
- Mast Cells/immunology
- Mast Cells/metabolism
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/immunology
- Membrane Glycoproteins/physiology
- Mice
- Mice, Inbred C57BL
- Orexin Receptors
- Receptors, Cell Surface
- Receptors, IgE/antagonists & inhibitors
- Receptors, IgE/physiology
- Skin/cytology
- Skin/immunology
- Skin/metabolism
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26
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Pasquier B, Launay P, Kanamaru Y, Moura IC, Pfirsch S, Ruffié C, Hénin D, Benhamou M, Pretolani M, Blank U, Monteiro RC. Identification of FcalphaRI as an inhibitory receptor that controls inflammation: dual role of FcRgamma ITAM. Immunity 2005; 22:31-42. [PMID: 15664157 DOI: 10.1016/j.immuni.2004.11.017] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2004] [Revised: 11/08/2004] [Accepted: 11/10/2004] [Indexed: 11/19/2022]
Abstract
Serum IgA is considered a discrete housekeeper of the immune system with multiple anti-inflammatory functions, whereas IgA-immune complexes mediate inflammatory responses. Here, we identify FcalphaRI as a molecular device that determines the nature of IgA responses. In the absence of sustained aggregation, receptor targeting by serum IgA or anti-FcalphaRI Fab inhibits activating responses of heterologous FcgammaR or FcepsilonRI. The inhibitory mechanism involves recruitment of tyrosine phosphatase SHP-1 to FcalphaRI and impairment of Syk, LAT, and ERK phosphorylation induced by FcepsilonRI engagement. SHP-1 recruitment is dependent on ERK. Conversely, sustained aggregation of FcalphaRI by multimeric ligands stimulates cell activation by recruiting high amounts of Syk and aborting SHP-1 binding. Both types of signals require the FcRgamma-ITAM motif. Anti-FcalphaRI Fab treatment suppresses manifestations of allergic asthma in FcalphaRI transgenic mice. These findings redefine FcalphaRI as a bifunctional inhibitory/activating receptor of the immune system that mediates both anti- and proinflammatory functions of IgA.
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Affiliation(s)
- Benoit Pasquier
- INSERM U699, Bichat Medical School, 16 rue Henri Huchard, 75870 Paris Cedex 18, France
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27
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Chodniewicz D, Klemke RL. Regulation of integrin-mediated cellular responses through assembly of a CAS/Crk scaffold. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2004; 1692:63-76. [PMID: 15246680 DOI: 10.1016/j.bbamcr.2004.03.006] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 11/03/2003] [Accepted: 03/16/2004] [Indexed: 01/09/2023]
Abstract
The molecular coupling of CAS and Crk in response to integrin activation is an evolutionary conserved signaling module that controls cell proliferation, survival and migration. However, when deregulated, CAS/Crk signaling also contributes to cancer progression and developmental defects in humans. Here we highlight recent advances in our understanding of how CAS/Crk complexes assemble in cells to modulate the actin cytoskeleton, and the molecular mechanisms that regulate this process. We discuss in detail the spatiotemporal dynamics of CAS/Crk assembly and how this scaffold recruits specific effector proteins that couple integrin signaling networks to the migration machinery of cells. We also highlight the importance of CAS/Crk signaling in the dual regulation of cell migration and survival mechanisms that operate in invasive cells during development and pathological conditions associated with cancer metastasis.
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Affiliation(s)
- David Chodniewicz
- Department of Immunology, The Scripps Research Institute, 10550 North Torrey Pines Road, SP231, La Jolla, CA 92037, USA
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28
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Young RM, Zheng X, Holowka D, Baird B. Reconstitution of regulated phosphorylation of FcepsilonRI by a lipid raft-excluded protein-tyrosine phosphatase. J Biol Chem 2004; 280:1230-5. [PMID: 15537644 DOI: 10.1074/jbc.m408339200] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To examine the exquisite regulation of IgE-FcepsilonRI tyrosine phosphorylation by Lyn kinase that is stimulated by antigen-mediated cross-linking, we utilized co-expression of FcepsilonRI and Lyn in Chinese hamster ovary cells, which results in high basal levels of Lyn kinase activity and spontaneous phosphorylation of FcepsilonRI. We found that co-expression of a lipid raft-excluded transmembrane tyrosine phosphatase, PTPalpha, suppresses Lyn kinase activity and markedly reduces the level of spontaneous phosphorylation of FcepsilonRI, while facilitating its antigen-stimulated phosphorylation. Other tyrosine phosphatases, including SHP-1, CD45, and a lipid raft-preferring chimeric version of PTPalpha fail to reconstitute antigen-dependent FcepsilonRI phosphorylation. We concluded that both substrate specificity and submembrane location are critical to phosphatase-mediated regulation of Lyn kinase activity that supports activation of FcepsilonRI.
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Affiliation(s)
- Ryan M Young
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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29
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Abstract
Apoptosis is a programmed mechanism of cell death recognized by its characteristic morphological and biochemical changes. Over the last decade, our understanding of the biochemistry of apoptosis has flourished. However, the physiological relevance of apoptosis remains elusive. Here, I propose that the process of programmed cell death plays an essential role in structural development. From pioneering studies almost a century ago to recent findings using modern technology, similar conclusions have emerged that highlight the fundamental role of apoptosis in vascular development. This review will recount these classic and modern studies as I survey evidence that implicates apoptosis in other aspects of development and ask how cell death can possibly contribute to homeostasis and development of the immune system. I briefly consider the mechanisms that may determine the fate of cells within the vasculature and propose new roles for the contribution of apoptosis to development and differentiation. More provocatively, I explore the possibilities that arise from this growing field of study, including prevention of developmental defects and even abnormal development after birth, such as neoplastic development. To realize these end points, the biochemical bases of apoptosis must be thoroughly understood.
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Affiliation(s)
- Andrea I Doseff
- The Dorothy M. Davis Heart and Lung Research Institute and Division of Pulmonary and Critical Care, Molecular Genetics, Ohio State University, Columbus, OH 43210, USA.
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Oda T, Ohka S, Nomoto A. Ligand stimulation of CD155alpha inhibits cell adhesion and enhances cell migration in fibroblasts. Biochem Biophys Res Commun 2004; 319:1253-64. [PMID: 15194502 DOI: 10.1016/j.bbrc.2004.05.111] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2004] [Indexed: 11/17/2022]
Abstract
CD155 (poliovirus receptor) localizes in cell-matrix adhesions and cell-cell junctions, but its role in the regulation of cell adhesion and cell motility has not been investigated. We identified a conserved immunoreceptor tyrosine-based inhibitory motif (ITIM) in the cytoplasmic domain of human CD155alpha. The ITIM was tyrosine-phosphorylated upon binding of anti-CD155 monoclonal antibody D171, poliovirus, and DNAM-1 (CD226) to human CD155alpha, and recruited SH2-domain-containing tyrosine phosphatase-2 (SHP-2). After CD155alpha stimulation with its ligands, cell adhesion was inhibited and cell motility was enhanced, effects that were associated with the phosphorylation of ITIM by Src kinases and accompanied by dephosphorylation of focal adhesion kinase and paxillin. These effects were abolished by introducing a point-mutation in Y398F into the ITIM of CD155alpha and by coexpression of a dominant negative SHP-2 mutant with CD155alpha. These results suggest that CD155alpha plays a role in the regulation of cell adhesion and cell motility.
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Affiliation(s)
- Toshiyuki Oda
- Department of Microbiology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
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Neznanov N, Neznanova L, Kondratov RV, O'Rourke DM, Ullrich A, Gudkov AV. The ability of protein tyrosine phosphatase SHP-1 to suppress NFkappaB can be inhibited by dominant negative mutant of SIRPalpha. DNA Cell Biol 2004; 23:175-82. [PMID: 15068587 DOI: 10.1089/104454904322964779] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In contrast with hematopoietic cells and fibroblasts, which express mainly one form of protein tyrosine phosphatase (PTP) SHP-1 or SHP-2, epithelial cells like A431, HeLa, and 293 express both forms of PTP. These two PTP regulate NFkappaB activity differently; SHP-1 inhibits and SHP-2 stimulates NFkappaB activation. In epithelial cells the process of NFkappaB activation depends on the combination of two PTP activities. The activity of PTP SHP-1 dominates in this tandem according to our data. The signal regulatory protein (SIRPalpha) is the adapter and the substrate of PTP SHP-1 and SHP-2. We investigated the role of SIRPalpha and its dominant negative mutant in PTP activities in 293 cells. The overexpression of wild-type SIRPalpha suppresses the activities of both PTP, but has a stronger effect on PTP SHP-2, especially when this protein is overexpressed in 293 cells. In contrast with wild-type SIRPalpha, its dominant negative mutant acts predominantly against PTP SHP-1, and can be detected in the complex with PTP SHP-1. The expression of dominant negative mutant of SIRPalpha has an effect similar to the expression of dominant negative PTP SHP-1 in the process of NFkappaB activation.
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Affiliation(s)
- Nickolay Neznanov
- Department of Virology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
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Erkeland SJ, Valkhof M, Heijmans-Antonissen C, van Hoven-Beijen A, Delwel R, Hermans MHA, Touw IP. Large-scale identification of disease genes involved in acute myeloid leukemia. J Virol 2004; 78:1971-80. [PMID: 14747562 PMCID: PMC369447 DOI: 10.1128/jvi.78.4.1971-1980.2004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Accepted: 10/27/2003] [Indexed: 11/20/2022] Open
Abstract
Acute myeloid leukemia (AML) is a heterogeneous group of diseases in which chromosomal aberrations, small insertions or deletions, or point mutations in certain genes have profound consequences for prognosis. However, the majority of AML patients present without currently known genetic defects. Retroviral insertion mutagenesis in mice has become a powerful tool for identifying new disease genes involved in the pathogenesis of leukemia and lymphoma. Here we have used the Graffi-1.4 strain of murine leukemia virus, which causes predominantly AML, in a screen to identify novel genes involved in the pathogenesis of this disease. We report 79 candidate disease genes in common integration sites (CISs) and 15 genes whose family members previously were found to be affected in other studies. The majority of the identified sequences (60%) were not found in lymphomas and monocytic leukemias in previous screens, suggesting a specific involvement in AML. Although most of the virus integrations occurred in or near the 5' or 3' ends of the genes, suggesting deregulation of gene expression as a consequence of virus integration, 18 CISs were located exclusively within the genes, conceivably causing gene disruption.
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Affiliation(s)
- Stefan J Erkeland
- Department of Hematology, Erasmus Medical Center, Rotterdam, The Netherlands
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Gagnon A, Artemenko Y, Crapper T, Sorisky A. Regulation of endogenous SH2 domain-containing inositol 5-phosphatase (SHIP2) in 3T3-L1 and human preadipocytes. J Cell Physiol 2003; 197:243-50. [PMID: 14502564 DOI: 10.1002/jcp.10367] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The role of the inositol lipid 5-phosphatase (SHIP2) in preadipocyte signaling is not known. Although overexpression of SHIP2 inhibited proliferation and (3)H-thymidine incorporation in 3T3-L1 preadipocytes, there was no effect on insulin-induced adipogenesis. Insulin promoted SHIP2 tyrosine phosphorylation in differentiated 3T3-L1 adipocytes, but did not do so in preadipocytes. The absence of SHIP2 tyrosine phosphorylation suggests a potential explanation for the isolated rise in PI(3,4,5)P3, without any changes in PI(3,4)P2, previously observed following insulin treatment of these cells. Lack of SHIP2 tyrosine phosphorylation by insulin was also observed in primary cultures of human abdominal subcutaneous preadipocytes. These cells also produced PI(3,4,5)P3, but not PI(3,4)P2, in response to insulin. Comparison of insulin vs. PDGF treatment on SHIP2 tyrosine phosphorylation in 3T3-L1 and human preadipocytes revealed that only PDGF, which stimulates the accumulation of PI(3,4,5)P3 as well as PI(3,4)P2, was active in this regard, and only PDGF promoted the association of 52 kDa form of Shc with SHIP2. Nevertheless, both insulin and PDGF were equally effective in translocating SHIP2 to the plasma membrane in 3T3-L1 preadipocytes. Lack of SHIP2 tyrosine phosphorylation may account for the insulin-specific inositol phospholipid pattern of accumulation in preadipocytes.
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Affiliation(s)
- Annemarie Gagnon
- Department of Medicine and Biochemistry, University of Ottawa, Ottawa Health Research Institute, Ottawa, Canada
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Martelli AM, Tazzari PL, Tabellini G, Bortul R, Billi AM, Manzoli L, Ruggeri A, Conte R, Cocco L. A new selective AKT pharmacological inhibitor reduces resistance to chemotherapeutic drugs, TRAIL, all-trans-retinoic acid, and ionizing radiation of human leukemia cells. Leukemia 2003; 17:1794-805. [PMID: 12970779 DOI: 10.1038/sj.leu.2403044] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
It is now well established that the reduced capacity of tumor cells of undergoing cell death through apoptosis plays a key role both in the pathogenesis of cancer and in therapeutic treatment failure. Indeed, tumor cells frequently display multiple alterations in signal transduction pathways leading to either cell survival or apoptosis. In mammals, the pathway based on phosphoinositide 3-kinase (PI3K)/Akt conveys survival signals of extreme importance and its downregulation, by means of pharmacological inhibitors of PI3K, considerably lowers resistance to various types of therapy in solid tumors. We recently described an HL60 leukemia cell clone (HL60AR cells) with a constitutively active PI3K/Akt pathway. These cells were resistant to multiple chemotherapeutic drugs, all-trans-retinoic acid (ATRA), and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Treatment with two pharmacological inhibitors of PI3K, wortmannin and Ly294002, restored sensitivity of HL60AR cells to the aforementioned treatments. However, these inhibitors have some drawbacks that may severely limit or impede their clinical use. Here, we have tested whether or not a new selective Akt inhibitor, 1L-6-hydroxymethyl-chiro-inositol 2(R)-2-O-methyl-3-O-octadecylcarbonate (Akt inhibitor), was as effective as Ly294002 in lowering the sensitivity threshold of HL60 cells to chemotherapeutic drugs, TRAIL, ATRA, and ionizing radiation. Our findings demonstrate that, at a concentration which does not affect PI3K activity, the Akt inhibitor markedly reduced resistance of HL60AR cells to etoposide, cytarabine, TRAIL, ATRA, and ionizing radiation. This effect was likely achieved through downregulation of expression of antiapoptotic proteins such as c-IAP1, c-IAP2, cFLIP(L), and of Bad phosphorylation on Ser 136. The Akt inhibitor did not influence PTEN activity. At variance with Ly294002, the Akt inhibitor did not negatively affect phosphorylation of protein kinase C-zeta and it was less effective in downregulating p70S6 kinase (p70S6K) activity. The Akt inhibitor increased sensitivity to apoptotic inducers of K562 and U937, but not of MOLT-4, leukemia cells. Overall, our results indicate that selective Akt pharmacological inhibitors might be used in the future for enhancing the sensitivity of leukemia cells to therapeutic treatments that induce apoptosis or for overcoming resistance to these treatments.
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Affiliation(s)
- A M Martelli
- Dipartimento di Scienze Anatomiche Umane e Fisiopatologia dell'Apparato Locomotore, Sezione di Anatomia, Cell Signalling Laboratory, Università di Bologna, Bologna, Italy
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