Genomes and Genes
PDGF Receptor Regulation by CBL
Principal Investigator: Hamid Band
Abstract: [unreadable] DESCRIPTION (provided by applicant): PDGF receptor tyrosine kinases play crucial physiological roles in cell proliferation, migration and differentiation during development, wound healing and tissue remodeling. Activation of these receptors is linked to cell proliferation; invasiveness and angiogenesis in human cancers, in particular glial tumors, and PDGFR fusion oncogenes are responsible for a subset of myelogenous leukemia. Indeed, inhibitors of PDGFR kinase activity are being evaluated as anti-cancer agents. Understanding the mechanisms that regulate the level of signaling downstream of PDGF receptors is therefore a major goal of research in cell and cancer biology. Ligand-induced downregulation, representing a balance between lysosomal degradation and recycling to cell surface, constitutes a major determinant of signaling potency of receptor tyrosine kinases. Our recent work has established the Cbl proto-oncoprotein as a crucial regulator of PDGF receptor down-regulation. Cbl, an ubiquitin ligase, targets activated PDGF receptors for ubiquitination that in turn facilitates their lysosomal sorting. How Cbl-dependent ubiquitination functions as a lysosomal sorting signal for PDGF receptors is unknown. Based on recent yeast genetic studies, we hypothesize the role of a novel endosomal sorting complex, ESCRT-1, which incorporates the TSG101 tumor suppressor protein, in Cbl- and ubiquitin-dependent lysosomal sorting of PDGF receptor. Here, we will test this hypothesis using a number of complementary approaches. We will use Cbl-deficient mouse embryonic fibroblasts, Cbl-insensitive PDGFR mutants expressed in PDGFR-null fibroblasts, cells with a conditional defect in ubiquitination, and PDGFR-ubiquitin fusion proteins to establish the essential role of Cbl-dependent ubiquitination in PDGFR down-regulation. We will use dual immunolabeling studies to identify the compartment(s) where Cbl-dependent lysosomal sorting of PDGFR occurs. We will use biochemical and co-localization analyses to establish that PDGFR and ESCRT-1 interact, and use over-expression and dominant-negative approaches to establish the requirement of this novel protein complex in lysosomal sorting of PDGFR. Functional analyses will assess if ESCRT-1 complex is critical in Cbl-mediated downregulation of PDGFR signaling. Insights gained through these studies should enhance the molecular understanding of a basic cellular process, downregulation of activated receptor tyrosine kinases. Given the role of PDGF receptors in maligant cell proliferation, invasiveness and angiogenesis, our studies are particularly relevant to cancer. Identification of novel regulatory mechanisms of receptor tyrosine kinase function may provide avenues to develop newer therapeutic agents and/or chemo- and radio-sensitizers.
Funding Period: 2003-03-01 - 2009-02-28
more information: NIH RePORT
- Endosomal-sorting complexes required for transport (ESCRT) pathway-dependent endosomal traffic regulates the localization of active Src at focal adhesionsChun Tu
Eppley Institute for Research in Cancer and Allied Diseases and University of Nebraska Medical Center Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
Proc Natl Acad Sci U S A 107:16107-12. 2010..These results reveal a critical role for an ESCRT pathway-dependent LE/LY trafficking step in Src function by promoting localization of active Src to FAs...
- Induction of cancer cell death by self-assembling nanostructures incorporating a cytotoxic peptideStephany M Standley
Department of Medicine, Robert H Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA
Cancer Res 70:3020-6. 2010..Our results provide proof-of-principle that self-assembling PAs can be rationally designed to generate nanostructures that can efficiently deliver cytotoxic peptides to cancer cells...
- Ehd4 is required to attain normal prepubertal testis size but dispensable for fertility in male miceManju George
Eppley Institute for Research in Cancer and Allied Diseases, UNMC Eppley Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska, USA
Genesis 48:328-42. 2010..Our results suggest a role for EHD4 in the proper development of postmitotic and postmeiotic germ cells and implicate EHD protein-mediated endocytic recycling as an important process in germ cell development and testis function...
- A combination of Trastuzumab and 17-AAG induces enhanced ubiquitinylation and lysosomal pathway-dependent ErbB2 degradation and cytotoxicity in ErbB2-overexpressing breast cancer cellsSrikumar M Raja
Eppley Institute for Research in Cancer and Allied Diseases, UNMC Eppley Cancer Center, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198 6805, USA
Cancer Biol Ther 7:1630-40. 2008..Our results suggest the 17-AAG and Trastuzumab combination as a mechanism-based combinatorial targeted therapy for ErbB2-overexpressing breast cancer patients...
- Lysosomal cathepsin B participates in the podosome-mediated extracellular matrix degradation and invasion via secreted lysosomes in v-Src fibroblastsChun Tu
Eppley Institute for Research in Cancer and Allied Diseases, and UNMC Eppley Cancer Center, Omaha, NE 68198 6805, USA
Cancer Res 68:9147-56. 2008..Overall, our results suggest that cathepsin B, delivered by lysosomal vesicles, is involved in the matrix degradtion of podosomes...
- Overexpression of RhoA induces preneoplastic transformation of primary mammary epithelial cellsXiangshan Zhao
Department of Genetics, Eppley Institute for Cancer and Allied Diseases and UNMC Eppley Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA
Cancer Res 69:483-91. 2009..Taken together, these results show that RhoA can induce the preneoplastic transformation of hMECs by altering multiple pathways linked to cellular transformation and breast cancer...
- The role of cooperativity with Src in oncogenic transformation mediated by non-small cell lung cancer-associated EGF receptor mutantsB M Chung
Eppley Institute for Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, 68198 6805, USA
Oncogene 28:1821-32. 2009....
- EHD4 and CDH23 are interacting partners in cochlear hair cellsSoma Sengupta
Department of Communication Sciences and Disorders, Hugh Knowles Center, Northwestern University, Evanston, Illinois 60208, USA
J Biol Chem 284:20121-9. 2009..Taken together, these data indicate that EHD4 is a novel CDH23-interacting protein that could regulate CDH23 trafficking/localization in a calcium-sensitive manner...
- Role of mammalian Ecdysoneless in cell cycle regulationJun Hyun Kim
Department of Genetics, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198 5805, USA
J Biol Chem 284:26402-10. 2009..Furthermore, Ecd directly bound to Rb at the pocket domain and competed with E2F for binding to hypophosphorylated Rb. Our results demonstrate that mammalian Ecd plays a role in cell cycle progression via the Rb-E2F pathway...
- Distinct roles for Rho versus Rac/Cdc42 GTPases downstream of Vav2 in regulating mammary epithelial acinar architectureLei Duan
Eppley Institute for Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA
J Biol Chem 285:1555-68. 2010..These results indicate that RhoA plays an antagonistic role to Rac1/Cdc42 in the control of mammary epithelial acinar morphogenesis...
- Biochemical characterization of human Ecdysoneless reveals a role in transcriptional regulationJun Hyun Kim
Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE 68198, USA
Biol Chem 391:9-19. 2010..Our results indicate an important function of human Ecd and provide a basis to explore the transcriptional partners of Ecd...
- Aberrant trafficking of NSCLC-associated EGFR mutants through the endocytic recycling pathway promotes interaction with SrcByung Min Chung
Eppley Institute for Cancer and Allied Diseases, University of Nebraska Medical Center, 985950 Nebraska Medical Center, Omaha, NE 68198 5950, USA
BMC Cell Biol 10:84. 2009..While numerous studies have examined mutant EGFR signaling, the endocytic traffic of mutant EGFR within the NSCLC milieu remains less clear...
- Upregulation of the let-7 microRNA with precocious development in lin-12/Notch hypermorphic Caenorhabditis elegans mutantsAharon Solomon
Division of Molecular Oncology, Evanston Northwestern Healthcare Research Institute, Department of Medicine, Feinberg School of Medicine, USA
Dev Biol 316:191-9. 2008..Importantly, the human microRNA let-7a was also upregulated in various human cell lines in response to Notch 1 activation, suggesting an evolutionarily conserved cross-talk between let-7 and the canonical lin-12/Notch signaling pathway...
- Cyclooxygenase-2 expression during immortalization and breast cancer progressionXiangshan Zhao
Division of Cancer Biology, Department of Medicine, Evanston Northwestern Healthcare Research Institute and Feinberg School of Medicine, Evanston, IL, USA
Cancer Res 68:467-75. 2008....
- Mammary epithelial cell transformation: insights from cell culture and mouse modelsGoberdhan Dimri
Division of Cancer Biology, Department of Medicine, ENH Research Institute, Robert H Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Evanston, Illinois, USA
Breast Cancer Res 7:171-9. 2005....
- Human kallikrein 10, a predictive marker for breast cancerYing Zhang
Division of Cancer Biology, Department of Medicine, Evanston Northwestern Healthcare Research Institute and Feinberg School of Medicine, Northwestern University, 1001 University Place, Evanston, IL 60201, USA
Biol Chem 387:715-21. 2006..These results point to the paradoxical role of hK10 in human cancers and underscore the importance of further studies of this kallikrein...
- The human orthologue of Drosophila ecdysoneless protein interacts with p53 and regulates its functionYing Zhang
Division of Cancer Biology and Molecular Oncology, Department of Medicine, Evanston Northwestern Healthcare Research Institute and Feinberg School of Medicine, and Robert H Lurie Comprehensive Cancer Center, Evanston, Illinois 60201, USA
Cancer Res 66:7167-75. 2006..Our studies also represent the first demonstration of a biochemical function for hEcd protein and raise the possibility that altered hEcd levels and/or function may contribute to oncogenesis...
- Shared as well as distinct roles of EHD proteins revealed by biochemical and functional comparisons in mammalian cells and C. elegansManju George
Division of Molecular Oncology, Evanston Northwestern Healthcare Research Institute, Department of Medicine, Feinberg School of Medicine, Northwestern University, Evanston, Illinois, USA
BMC Cell Biol 8:3. 2007..Certain members of this family have been studied in different cellular contexts; however, a lack of concurrent analyses of all four proteins has impeded an appreciation of their redundant versus distinct functions...
- An essential role of human Ada3 in p53 acetylationAlo Nag
Division of Cancer Biology, Evanston Northwestern Healthcare Research Institute, IL 60201, USA
J Biol Chem 282:8812-20. 2007....
- The notch regulator MAML1 interacts with p53 and functions as a coactivatorYongtong Zhao
Division of Cancer Biology, Department of Medicine, ENH Research Institute, Feinberg School of Medicine, Northwestern University, Evanston, Illinois 60201, USA
J Biol Chem 282:11969-81. 2007..elegans p53 homolog Cep-1. Thus, we present evidence for a novel coactivator function of MAML1 for p53, independent of its function as a coactivator of Notch signaling pathway...
- A critical role for the E3-ligase activity of c-Cbl in VEGFR-2-mediated PLCgamma1 activation and angiogenesisAmrik J Singh
Department of Periodontology, Boston University Medical School, Boston, MA 02118, USA
Proc Natl Acad Sci U S A 104:5413-8. 2007..Our data demonstrate that corecruitment of c-Cbl and PLCgamma1 to VEGFR-2 serves as a mechanism to fine-tune the angiogenic signal relay of VEGFR-2...
- Modeling breast cancer-associated c-Src and EGFR overexpression in human MECs: c-Src and EGFR cooperatively promote aberrant three-dimensional acinar structure and invasive behaviorManjari Dimri
Division of Molecular Oncology, Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201, USA
Cancer Res 67:4164-72. 2007....
- Binding of Cbl to a phospholipase Cgamma1-docking site on platelet-derived growth factor receptor beta provides a dual mechanism of negative regulationAlagarsamy Lakku Reddi
Division of Molecular Oncology, Evanston Northwestern Healthcare Research Institute, Northwestern University, Evanston, Illinois 60201, USA
J Biol Chem 282:29336-47. 2007....
- c-Cbl is not required for ERK1/2-dependent degradation of BimELCeri M Wiggins
Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
Cell Signal 19:2605-11. 2007..These results indicate that Cbl is not required for ERK1/2-dependent Bim(EL) turnover in fibroblasts and epithelial cells and any role it has in other cell types is likely to be indirect...
- Ada3 requirement for HAT recruitment to estrogen receptors and estrogen-dependent breast cancer cell proliferationAleksandra Germaniuk-Kurowska
Divisions of Cancer Biology, Evanston Northwestern Healthcare Research Institute, Northwestern University, Evanston, Illinois, USA
Cancer Res 67:11789-97. 2007..Thus, our results show an important role of Ada3 in HAT recruitment to estrogen-responsive target gene promoters and for estrogen-dependent proliferation of breast cancer cells...
- The carboxyl terminus of VEGFR-2 is required for PKC-mediated down-regulationAmrik J Singh
Department of Ophthalmology, Boston University School of Medicine, MA 02118, USA
Mol Biol Cell 16:2106-18. 2005..Altogether the results show that the regulatory mechanisms involved in the attenuation of VEGFR-2 activation is mediated by nonclassical PKCs and the presence of serine sites in the carboxyl terminal of VEGFR-2...