PKC/PKA Regulation in Prostate Cancer by SSeCKS/Gravin/AKAP12

Summary

Principal Investigator: Irwin H Gelman
Abstract: DESCRIPTION (provided by applicant): Activation of protein kinase (PK) C has been considered cancer-promoting based on early data showing that phorbol esters could induce oncogenes is through the activation of so called classic and novel PKC isozymes. Although many human cancers exhibit increased levels of specific PKC isozymes there are conflicting data which show that specific isozymes can act as either promoters or suppressors of oncogenesis depending on tissue context. In human prostate cancer (CaP), PKC, levels increase with malignancy whereas PKC* levels are constant, yet only the overexpression of PKC, is sufficient to induce prostatic intraepithelial neoplasia (PIN). Therefore, characterization of the pro-oncogenic PKC-induced signaling pathways and mediators is paramount to our overall understanding of CaP disease progression. Our lab identified a novel PKC substrate, SSeCKS/Gravin/AKAP12 ("SSeCKS") that is also a scaffold for both PKC and PKA, capable of attenuating PKC kinase activity and altering its cellular compartmentalization, while regulating PKA through compartmentalization only. SSeCKS displays many of the hallmarks of a tumor suppressor in prostate cancer: it is severely downregulated in human CaP cell lines and tissues with Gleason sums =6, SSeCKS reexpression suppresses macroscopic CaP metastasis growth by inhibiting VEGF-induced neovascularization, genetic knockout (KO) in mice induces prostatic hyperplasia and focal dysplasia with evidence of epithelial cell senescence, and KO mouse fibroblasts (MEF) display premature senescence correlating with polyploidy and binucleation. Premature senescence seems Rb-dependent because it can be suppressed by HPV-16E7orpRb-siRNA but not byHPV-16 E6 or p53-siRNA. In keeping with SSeCKS'scaffolding function for PKC, KO-MEF have >2-fold higher total PKC activity than WT-MEF, with a >3-fold increase in PKC* activity. Based on preliminary data from expression microarray and biochemical experiments, we hypothesize the loss of SSeCKS induces hyperactive PKC*/,,which in turn induce i) cytokinesis defects through the activation of RhoA and LIMK, and through the suppression of the mitotic exit network kinase, WARTS, and ii) Rb-dependent senescence by increasing reactive oxygen species (ROS) mediators such as p47phox. We believe SSeCKS controls cytokinesis directly because a pool of SSeCKS enriches in the cleavage furrow during telophase where PKC* and , are known to normally regulate abscission by coordinating the timing of RhoA and LIMK activation, and thus, formation and contraction of the actomyosin abscission ring. Our overall aim is to use genetic, biochemical, and fluorescence and time-lapse microscopy techniques to dissect this novel SSeCKS-PKC pathway in WT vs. KO MEF and murine prostate epithelial cells (PrEC), and in human PrEC vs. CaP cell lines, using readouts of senescence/ polyploidy/ binucleation and cytokinesis completion (Aim 1), podosome formation and tumor invasiveness (Aim 2), and CaP formation, invasiveness and metastatic potential in transgenic mouse models (Aim 3). The experiments proposed are envisioned to elucidate the mechanism and pathways controlled by the SSeCKS/PKC scaffold complex and how dysregulation by the loss of SSeCKS contributes to CaP progression. PUBLIC HEALTH RELEVANCE: Our project focuses on SSeCKS, a protein that seems to suppress prostate cancer progression especially metastasis, by binding two opposing signaling proteins, PKA and PKC, and controlling their function by regulating when and where in the cell they are activated. We now propose to elaborate on pro-cancer pathways that PKC induces, yet which are normally regulated by SSeCKS. These studies will elucidate how the loss of SSeCKS expression in prostate cancer increases disease progression by allowing PKC to be hyperactivated and dysregulated.
Funding Period: 2001-12-01 - 2015-01-31
more information: NIH RePORT

Top Publications

  1. ncbi SSeCKS/Gravin/AKAP12 metastasis suppressor inhibits podosome formation via RhoA- and Cdc42-dependent pathways
    Irwin H Gelman
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    Mol Cancer Res 4:151-8. 2006
  2. pmc Control of protein kinase C activity, phorbol ester-induced cytoskeletal remodeling, and cell survival signals by the scaffolding protein SSeCKS/GRAVIN/AKAP12
    Li Wu Guo
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
    J Biol Chem 286:38356-66. 2011
  3. ncbi PTPN14 interacts with and negatively regulates the oncogenic function of YAP
    X Liu
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
    Oncogene 32:1266-73. 2013
  4. pmc Suppression of tumor and metastasis progression through the scaffolding functions of SSeCKS/Gravin/AKAP12
    Irwin H Gelman
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    Cancer Metastasis Rev 31:493-500. 2012
  5. pmc Adhesion-mediated cytoskeletal remodeling is controlled by the direct scaffolding of Src from FAK complexes to lipid rafts by SSeCKS/AKAP12
    B Su
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
    Oncogene 32:2016-26. 2013
  6. pmc Pivotal Role of AKAP12 in the Regulation of Cellular Adhesion Dynamics: Control of Cytoskeletal Architecture, Cell Migration, and Mitogenic Signaling
    Shin Akakura
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    J Signal Transduct 2012:529179. 2012
  7. pmc Proximal tubular cells contain a phenotypically distinct, scattered cell population involved in tubular regeneration
    Bart Smeets
    Division of Nephrology and Immunology, University Hospital of the Aachen University of Technology RWTH, Aachen, Germany
    J Pathol 229:645-59. 2013
  8. pmc Gravin orchestrates protein kinase A and β2-adrenergic receptor signaling critical for synaptic plasticity and memory
    Robbert Havekes
    Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 6018, USA
    J Neurosci 32:18137-49. 2012
  9. pmc Emerging Roles for SSeCKS/Gravin/AKAP12 in the Control of Cell Proliferation, Cancer Malignancy, and Barriergenesis
    Irwin H Gelman
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
    Genes Cancer 1:1147-56. 2010
  10. pmc Retinoid-induced expression and activity of an immediate early tumor suppressor gene in vascular smooth muscle cells
    Jeffrey W Streb
    Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
    PLoS ONE 6:e18538. 2011

Research Grants

Detail Information

Publications23

  1. ncbi SSeCKS/Gravin/AKAP12 metastasis suppressor inhibits podosome formation via RhoA- and Cdc42-dependent pathways
    Irwin H Gelman
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    Mol Cancer Res 4:151-8. 2006
    ..Additionally, they strengthen the notion that SSeCKS suppresses Src-induced oncogenesis by reestablishing actin-based cytoskeletal architecture...
  2. pmc Control of protein kinase C activity, phorbol ester-induced cytoskeletal remodeling, and cell survival signals by the scaffolding protein SSeCKS/GRAVIN/AKAP12
    Li Wu Guo
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
    J Biol Chem 286:38356-66. 2011
    ..Thus, PKC-mediated remodeling of the actin cytoskeleton is likely regulated by the ability of SSeCKS to control PKC signaling and activity through a direct scaffolding function...
  3. ncbi PTPN14 interacts with and negatively regulates the oncogenic function of YAP
    X Liu
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
    Oncogene 32:1266-73. 2013
    ..In summary, our results indicate a potential regulatory role of PTPN14 on YAP and demonstrate a novel mechanism in YAP regulation...
  4. pmc Suppression of tumor and metastasis progression through the scaffolding functions of SSeCKS/Gravin/AKAP12
    Irwin H Gelman
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    Cancer Metastasis Rev 31:493-500. 2012
    ..The current review will describe the emerging understanding of how AKAP12 regulates cellular senescence and oncogenic progression at the level of tumor cells and tumor-associated microenvironment via its multiple scaffolding functions...
  5. pmc Adhesion-mediated cytoskeletal remodeling is controlled by the direct scaffolding of Src from FAK complexes to lipid rafts by SSeCKS/AKAP12
    B Su
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
    Oncogene 32:2016-26. 2013
    ..Our data suggest a model in which SSeCKS suppresses oncogenic motility by sequestering Src to caveolin-rich lipid rafts, thereby disengaging Src from FAK-associated adhesion and signaling complexes...
  6. pmc Pivotal Role of AKAP12 in the Regulation of Cellular Adhesion Dynamics: Control of Cytoskeletal Architecture, Cell Migration, and Mitogenic Signaling
    Shin Akakura
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    J Signal Transduct 2012:529179. 2012
    ..The paper describes the regulatory and scaffolding functions of AKAP12 and how it regulates cell adhesion, signaling, and oncogenic suppression...
  7. pmc Proximal tubular cells contain a phenotypically distinct, scattered cell population involved in tubular regeneration
    Bart Smeets
    Division of Nephrology and Immunology, University Hospital of the Aachen University of Technology RWTH, Aachen, Germany
    J Pathol 229:645-59. 2013
    ..Our data indicate rather that these cells represent transiently dedifferentiated tubular cells involved in regeneration...
  8. pmc Gravin orchestrates protein kinase A and β2-adrenergic receptor signaling critical for synaptic plasticity and memory
    Robbert Havekes
    Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 6018, USA
    J Neurosci 32:18137-49. 2012
    ....
  9. pmc Emerging Roles for SSeCKS/Gravin/AKAP12 in the Control of Cell Proliferation, Cancer Malignancy, and Barriergenesis
    Irwin H Gelman
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
    Genes Cancer 1:1147-56. 2010
    ....
  10. pmc Retinoid-induced expression and activity of an immediate early tumor suppressor gene in vascular smooth muscle cells
    Jeffrey W Streb
    Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
    PLoS ONE 6:e18538. 2011
    ....
  11. pmc Carcinogen-induced squamous papillomas and oncogenic progression in the absence of the SSeCKS/AKAP12 metastasis suppressor correlate with FAK upregulation
    Shin Akakura
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
    Int J Cancer 129:2025-31. 2011
    ..RNAi studies in WT MEF cells suggest that SSeCKS and FAK attenuate each other's expression. Our study implicates a role for SSeCKS in preventing of skin cancer progression possibly through negatively regulating FAK expression...
  12. pmc SSeCKS/Gravin/AKAP12 attenuates expression of proliferative and angiogenic genes during suppression of v-Src-induced oncogenesis
    Yongzhong Liu
    Mucosal Immunology Unit, National Institutes of Health, Bethesda, MD 20892, USA
    BMC Cancer 6:105. 2006
    ....
  13. ncbi SSeCKS metastasis-suppressing activity in MatLyLu prostate cancer cells correlates with vascular endothelial growth factor inhibition
    Bing Su
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, New York, USA
    Cancer Res 66:5599-607. 2006
    ..These results suggest that SSeCKS suppresses formation of metastatic lesions by inhibiting VEGF expression and by inducing soluble antiangiogenic factors...
  14. ncbi v-Src-mediated down-regulation of SSeCKS metastasis suppressor gene promoter by the recruitment of HDAC1 into a USF1-Sp1-Sp3 complex
    Yahao Bu
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    J Biol Chem 282:26725-39. 2007
    ..Our data suggest that suppression of the beta promoter is facilitated by Src-induced changes in the alpha promoter chromatinization mediated by a USF1-Sp1-Sp3 complex...
  15. pmc Loss of the SSeCKS/Gravin/AKAP12 gene results in prostatic hyperplasia
    Shin Akakura
    Department of Cancer Genetics, Therapeutics Roswell Park Cancer Institute, Buffalo, New York 14263, USA
    Cancer Res 68:5096-103. 2008
    ..The data suggest that SSeCKS-null mice have increased susceptibility for oncogenic transformation in the prostate...
  16. pmc Paxillin-Y118 phosphorylation contributes to the control of Src-induced anchorage-independent growth by FAK and adhesion
    Sanjay Sachdev
    Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
    BMC Cancer 9:12. 2009
    ....
  17. pmc SSeCKS/Gravin/AKAP12 inhibits cancer cell invasiveness and chemotaxis by suppressing a protein kinase C- Raf/MEK/ERK pathway
    Bing Su
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
    J Biol Chem 285:4578-86. 2010
    ..Our findings suggest that SSeCKS suppresses metastatic motility by disengaging activated Src and then inhibiting the PKC-Raf/MEK/ERK pathways controlling matrix metalloproteinase-2 expression and podosome formation...
  18. pmc Role for transcription factor TFII-I in the suppression of SSeCKS/Gravin/Akap12 transcription by Src
    Yahao Bu
    Kinex Pharmaceuticals, LLC, Buffalo, NY, USA
    Int J Cancer 128:1836-42. 2011
    ....
  19. pmc Rb-dependent cellular senescence, multinucleation and susceptibility to oncogenic transformation through PKC scaffolding by SSeCKS/AKAP12
    Shin Akakura
    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
    Cell Cycle 9:4656-65. 2010
    ..Our data strongly suggest that Akap12 controls Rb-mediated cell aging and oncogenic progression by directly scaffolding and attenuating PKCα/δ...
  20. pmc A transgenic mouse model for early prostate metastasis to lymph nodes
    Hyun Kyung Ko
    Authors Affiliations Departments of Cancer Genetics and Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York
    Cancer Res 74:945-53. 2014
    ..Taken together, these data suggest that in the context of Rb loss, Akap12 suppresses the oncogenic proliferation and early metastatic spread of basal-luminal prostate tumor cells...

Research Grants30

  1. FoxM1 in tumor cell
    Pradip Raychaudhuri; Fiscal Year: 2013
    ..These studies will establish the functions of FoxM1 in tumor development and progression, as well as establish a role of FoxM1 over expression in the development of drug resistance. ..
  2. Molecular Response and Imaging-based Combination Strategies for Optimal PDT
    Tayyaba Hasan; Fiscal Year: 2013
    ..NMSC on the other hand has many options but the high incidence puts a heavy burden on society in terms of cost and suffering. ..
  3. MODULATION OF HOST CELL APOPTOTIC RESPONSES BY HPVE7
    Karl Munger; Fiscal Year: 2013
    ..abstract_text> ..
  4. Expanding Excellence in Developmental Biology in Oklahoma
    Linda F Thompson; Fiscal Year: 2013
    ..abstract_text> ..