RNA Binding Protein CUGBP2 in Intestinal Epithelium

Summary

Principal Investigator: Shrikant Anant
Abstract: DESCRIPTION (provided by applicant): The broad goal of this application is to understand the mechanisms by which RNA binding protein CUGBP2 regulates gene expression at the posttranscriptional level of mRNA stability and translation in intestinal epithelial cells. Overexpression of the protein in cancer cells results in cell death. We have determined that CUGBP2 interacts with AU-rich sequences in the 3'untranslated region of cyclooxygenase-2 and Mcl-1 mRNAs and upon binding downregulates the translation of both mRNAs. We have also determined that CUGBP2 levels are decreased in cancer cells but its expression is elevated in cells undergoing mitotic catastrophe. In addition, CUGBP2 is regulated at the levels of transcription by three different promoters. Activation from promoters located upstream from the commonly used proximal promoter results in the inclusion of additional amino acids in the N-terminus of the protein. Our studies suggest that the consequence of this addition is differences in cellular localization of the protein, but more importantly in the activity of the protein. The variants with the added amino acids do not affect cell viability. In addition, there are differential effects on target gene splicing with the three variants. Based on these observations, we have proposed to determine three aims. In Aim 1, we will determine the mechanism(s) by which the three CUGBP2 promoters are regulated. In addition, CUGBP2 is regulated at the posttranscriptional level of alternative splicing resulting in the novel inclusion of one intron in the 5'untranslated region. We will identify the cis-acting sequences and trans-acting factors regulating this process. In Aim 2, we will determine the cellular functions of CUGBP2. We have identified cellular factors that bind to CUGBP2. We will perform systematic deletion and fine mutagenesis to identify the domains in CUGBP2 that are involved in RNA:protein and protein:protein interactions. In addition, we will determine the CUGBP2 domains that regulate CUGBP2 localization under basal conditions and when the cells are exposed to 3-irradiation. We will also determine the effect of these interactions on CUGBP2 mediated RNA splicing, mRNA stability and translation regulation. In Aim 3, we will determine whether the CUGBP2 gene is both a novel tumor suppressor and a protooncogene. We will determine the expression levels of the three isoforms in a panel of human colon tumors. Furthermore, we will determine whether the different CUGBP2 isoforms affect tumor behavior in xenograft models. Completion of these experiments should give us a better understanding of how the RNA binding protein CUGBP2 functions in normal epithelial cells, and whether changes in the CUGBP2 expression that is observed in tumor cells is responsible for tumor behavior. PUBLIC HEALTH RELEVANCE: Colorectal cancer is the leading in cancer related deaths in the United States. Understanding how the normal cell progresses to a cancer will aid in our developing novel therapies for both diseases. We have identified a protein, CUGBP2 whose expression is lost in cancer cells. Restoring the protein into the cancer cell kills the cells. We are in the process of identifying how the gene expressing CUGBP2 is silenced in cancer cells so that we can determine ways to reverse the process. This might stop or slow down the tumorigenesis.
Funding Period: ----------------2009 - ---------------2011-
more information: NIH RePORT

Top Publications

  1. ncbi Reg IV activates the epidermal growth factor receptor/Akt/AP-1 signaling pathway in colon adenocarcinomas
    Kumar S Bishnupuri
    Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA
    Gastroenterology 130:137-49. 2006
  2. pmc CDK-4 inhibitor P276 sensitizes pancreatic cancer cells to gemcitabine-induced apoptosis
    Dharmalingam Subramaniam
    Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
    Mol Cancer Ther 11:1598-608. 2012
  3. pmc Honokiol in combination with radiation targets notch signaling to inhibit colon cancer stem cells
    Sivapriya Ponnurangam
    Department of Molecular and Integrative Physiology, The University of Kansas Medical Center, Kansas City, Kansas 66160, USA
    Mol Cancer Ther 11:963-72. 2012
  4. pmc DCAMKL-1 regulates epithelial-mesenchymal transition in human pancreatic cells through a miR-200a-dependent mechanism
    Sripathi M Sureban
    Department of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
    Cancer Res 71:2328-38. 2011
  5. pmc Doublecortin and CaM kinase-like-1 and leucine-rich-repeat-containing G-protein-coupled receptor mark quiescent and cycling intestinal stem cells, respectively
    Randal May
    Department of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
    Stem Cells 27:2571-9. 2009
  6. pmc Translation regulatory factor RBM3 is a proto-oncogene that prevents mitotic catastrophe
    S M Sureban
    Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126, USA
    Oncogene 27:4544-56. 2008
  7. ncbi Gastrin-mediated interleukin-8 and cyclooxygenase-2 gene expression: differential transcriptional and posttranscriptional mechanisms
    Dharmalingam Subramaniam
    Department of Internal Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
    Gastroenterology 134:1070-82. 2008
  8. ncbi Diphenyl difluoroketone: a curcumin derivative with potent in vivo anticancer activity
    Dharmalingam Subramaniam
    Section of Digestive Diseases and Nutrition, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126, USA
    Cancer Res 68:1962-9. 2008
  9. ncbi CUGBP2 downregulation by prostaglandin E2 protects colon cancer cells from radiation-induced mitotic catastrophe
    Gopalan Natarajan
    Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
    Am J Physiol Gastrointest Liver Physiol 294:G1235-44. 2008
  10. ncbi Azoxymethane protects intestinal stem cells and reduces crypt epithelial mitosis through a COX-1-dependent mechanism
    Terrence E Riehl
    Division of Gastroenterology, Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri, USA
    Am J Physiol Gastrointest Liver Physiol 291:G1062-70. 2006

Scientific Experts

  • Dharmalingam Subramaniam
  • Shrikant Anant
  • Courtney W Houchen
  • Randal May
  • Sripathi M Sureban
  • Kumar S Bishnupuri
  • Satish Ramalingam
  • Brian K Dieckgraefe
  • Robert J George
  • Zhiyun He
  • Gopalan Natarajan
  • Mark A Sturmoski
  • Qizhi Luo
  • Terrence E Riehl
  • William G Gutheil
  • Kaustuv Sahoo
  • Sivapriya Ponnurangam
  • Shahid Umar
  • Youcheng Zhang
  • Animesh Dhar
  • Russell G Postier
  • James H Wyche
  • Rama Ramanujam
  • Stan A Lightfoot
  • Ilangovan Ramachandran
  • Lurdes Queimado
  • S M Sureban
  • Shien Hu
  • Nabendu Murmu
  • Vibhudutta Awasthi
  • Joshua M V Mammen
  • Amitabha Ray
  • Mikhail G Dozmorov
  • Gregory Reed
  • Megan Lerner
  • Altaf Mohammed
  • Daniel J Brackett
  • Aimee B Hoskins
  • Chinthalapally V Rao
  • Jennifer H Gross
  • Kento Kikuchi
  • Satheesh K Sainathan
  • Mekala Sabarinathan
  • Konrad Aden
  • Nguyet Hoang
  • R May
  • K S Bishnupuri
  • Chris Schafer
  • R G Postier
  • S Ramalingam
  • B K Dieckgraefe
  • S Anant
  • C W Houchen
  • A R Morrison
  • G Natarajan
  • D J Brackett
  • Maor Lahav
  • Pavel Rodriguez
  • Lev Lichtenstein
  • Mikihiro Fujiya
  • Mark W Musch
  • Mae J Ciancio
  • Reeti Maheshwari
  • Eugene B Chang
  • Joshua R Korzenik
  • Jeffrey O Henderson
  • Brian Dieckgraefe

Detail Information

Publications27

  1. ncbi Reg IV activates the epidermal growth factor receptor/Akt/AP-1 signaling pathway in colon adenocarcinomas
    Kumar S Bishnupuri
    Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA
    Gastroenterology 130:137-49. 2006
    ..However, in vitro signal transduction pathway(s) utilized by Reg IV are not yet known...
  2. pmc CDK-4 inhibitor P276 sensitizes pancreatic cancer cells to gemcitabine-induced apoptosis
    Dharmalingam Subramaniam
    Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
    Mol Cancer Ther 11:1598-608. 2012
    ..Taken together, these data suggest that P276-Gem combination is a novel potent therapeutic agent that can target the Akt-mTOR signaling pathway to inhibit both tumor growth and angiogenesis...
  3. pmc Honokiol in combination with radiation targets notch signaling to inhibit colon cancer stem cells
    Sivapriya Ponnurangam
    Department of Molecular and Integrative Physiology, The University of Kansas Medical Center, Kansas City, Kansas 66160, USA
    Mol Cancer Ther 11:963-72. 2012
    ..These studies warrant further clinical evaluation for the combination of honokiol and IR for treating colon cancers...
  4. pmc DCAMKL-1 regulates epithelial-mesenchymal transition in human pancreatic cells through a miR-200a-dependent mechanism
    Sripathi M Sureban
    Department of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
    Cancer Res 71:2328-38. 2011
    ..Moreover, they demonstrate a functional role for DCAMKL-1 in pancreatic cancer. Together, our results rationalize DCAMKL-1 as a therapeutic target for eradicating pancreatic cancers...
  5. pmc Doublecortin and CaM kinase-like-1 and leucine-rich-repeat-containing G-protein-coupled receptor mark quiescent and cycling intestinal stem cells, respectively
    Randal May
    Department of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
    Stem Cells 27:2571-9. 2009
    ..Moreover, DCAMKL-1 can be used to isolate normal small intestinal stem cells and represents a novel research tool for regenerative medicine and cancer therapy...
  6. pmc Translation regulatory factor RBM3 is a proto-oncogene that prevents mitotic catastrophe
    S M Sureban
    Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126, USA
    Oncogene 27:4544-56. 2008
    ..These data demonstrate that the RNA stabilizing and translation regulatory protein RBM3 is a novel proto-oncogene that induces transformation when overexpressed and is essential for cells to progress through mitosis...
  7. ncbi Gastrin-mediated interleukin-8 and cyclooxygenase-2 gene expression: differential transcriptional and posttranscriptional mechanisms
    Dharmalingam Subramaniam
    Department of Internal Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
    Gastroenterology 134:1070-82. 2008
    ..Here, we have determined the intracellular mechanisms mediating gastrin-dependent gene expression...
  8. ncbi Diphenyl difluoroketone: a curcumin derivative with potent in vivo anticancer activity
    Dharmalingam Subramaniam
    Section of Digestive Diseases and Nutrition, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126, USA
    Cancer Res 68:1962-9. 2008
    ..Taken together, these data suggest that the novel curcumin-related compound EF24 is a potent antitumor agent that induces caspase-mediated apoptosis during mitosis and has significant therapeutic potential for gastrointestinal cancers...
  9. ncbi CUGBP2 downregulation by prostaglandin E2 protects colon cancer cells from radiation-induced mitotic catastrophe
    Gopalan Natarajan
    Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
    Am J Physiol Gastrointest Liver Physiol 294:G1235-44. 2008
    ..Taken together, these data demonstrate that PGE(2) protects colon cancer cells from IR-induced mitotic catastrophe in part through suppression of CUGBP2 expression...
  10. ncbi Azoxymethane protects intestinal stem cells and reduces crypt epithelial mitosis through a COX-1-dependent mechanism
    Terrence E Riehl
    Division of Gastroenterology, Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri, USA
    Am J Physiol Gastrointest Liver Physiol 291:G1062-70. 2006
    ..This suggests that COX-1-derived PGE(2) may play a key role in the early phase of intestinal tumorigenesis in response to DNA damage and suggests that COX-1 may be a potential therapeutic target in this model of colon cancer...
  11. ncbi Dysregulation of Reg gene expression occurs early in gastrointestinal tumorigenesis and regulates anti-apoptotic genes
    Kumar S Bishnupuri
    Division of Gastroenterology, Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri 63110, and Massachusetts General Hospital, Boston, USA
    Cancer Biol Ther 5:1714-20. 2006
    ..Furthermore, increased expression of Reg genes, specifically Reg IV contribute to adenoma formation and lead to increased resistance to apoptotic cell death in CRC...
  12. pmc EP4 mediates PGE2 dependent cell survival through the PI3 kinase/AKT pathway
    Robert J George
    Washington University School of Medicine, Department of Internal Medicine, St Louis, Missouri 63110, USA
    Prostaglandins Other Lipid Mediat 83:112-20. 2007
    ..These findings have critical implications regarding the mechanism and potential application of PGE(2) receptor specific inhibition in cancer therapy...
  13. ncbi Functional antagonism between RNA binding proteins HuR and CUGBP2 determines the fate of COX-2 mRNA translation
    Sripathi M Sureban
    Department of Medicine, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma 73104, USA
    Gastroenterology 132:1055-65. 2007
    ..This study aimed to determine the antagonism between these proteins on COX-2 expression...
  14. ncbi Translation inhibition during cell cycle arrest and apoptosis: Mcl-1 is a novel target for RNA binding protein CUGBP2
    Dharmalingam Subramaniam
    Dept of Medicine, Univ of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
    Am J Physiol Gastrointest Liver Physiol 294:G1025-32. 2008
    ..Taken together, these data demonstrate that CUGBP2 inhibits Mcl-1 expression by inhibiting Mcl-1 mRNA translation, resulting in driving the cells to apoptosis during the G(2) phase of the cell cycle...
  15. ncbi Novel intestinal splice variants of RNA-binding protein CUGBP2: isoform-specific effects on mitotic catastrophe
    Satish Ramalingam
    Dept of Medicine, Univ of Oklahoma Health Sciences Ctr, 920 Stanton L Young Blvd, WP1360, Oklahoma City, OK 73126, USA
    Am J Physiol Gastrointest Liver Physiol 294:G971-81. 2008
    ..Taken together, these data demonstrate that cells expressing CUGBP2 variant 1 undergo apoptosis during mitosis, suggesting mitotic catastrophe...
  16. pmc Translational inhibition of colonic epithelial heat shock proteins by IFN-gamma and TNF-alpha in intestinal inflammation
    Shien Hu
    The Martin Boyer Laboratories, Department of Medicine, University of Chicago IBD Research Center, Chicago, Illinois, USA
    Gastroenterology 133:1893-904. 2007
    ..We examined the expression and regulation of iHsp in human and experimental inflammatory bowel diseases (IBD) and in vitro...
  17. pmc Loss of p21Waf1/Cip1/Sdi1 enhances intestinal stem cell survival following radiation injury
    Robert J George
    Department of Internal Medicine, Division of Gastroenterology, Washington University School of Medicine, St Louis, Missouri, USA
    Am J Physiol Gastrointest Liver Physiol 296:G245-54. 2009
    ..Furthermore, the increase in crypt survival is associated with increased numbers of Msi-1- and survivin-expressing cells in regenerative crypts...
  18. pmc 3,5-bis(2,4-difluorobenzylidene)-4-piperidone, a novel compound that affects pancreatic cancer growth and angiogenesis
    Dharmalingam Subramaniam
    Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160, USA
    Mol Cancer Ther 10:2146-56. 2011
    ..Taken together, these data suggest that DiFiD is a novel potent therapeutic agent that can target different aspects of the Notch signaling pathway to inhibit both tumor growth and angiogenesis...
  19. pmc Honokiol radiosensitizes colorectal cancer cells: enhanced activity in cells with mismatch repair defects
    Zhiyun He
    Department of Medicine, Lanzhou University Second Hospital, Gansu Province, China
    Am J Physiol Gastrointest Liver Physiol 301:G929-37. 2011
    ..These data demonstrate that honokiol is highly effective in radiosensitizing colorectal cancer cells, especially those with a mismatch repair defect...
  20. ncbi Crocetin: an agent derived from saffron for prevention and therapy for cancer
    William G Gutheil
    Pharmaceutical Sciences, School of Pharmacy, University of Missouri Kansas City, MO, USA
    Curr Pharm Biotechnol 13:173-9. 2012
    ..This review discusses the studies on cancer preventive potential of crocetin and its future use as an anticancer agent...
  21. pmc RNA binding protein CUGBP2/CELF2 mediates curcumin-induced mitotic catastrophe of pancreatic cancer cells
    Dharmalingam Subramaniam
    Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
    PLoS ONE 6:e16958. 2011
    ..Here, we have determined that curcumin modulates the expression of RNA binding protein CUGBP2 to inhibit pancreatic cancer growth...
  22. pmc The curcuminoid CLEFMA selectively induces cell death in H441 lung adenocarcinoma cells via oxidative stress
    Kaustuv Sahoo
    Department of Pharmaceutical Sciences, University of Oklahoma Health Science Center, 1110 North Stonewall Avenue, Oklahoma, OK 73117, USA
    Invest New Drugs 30:558-67. 2012
    ..Based on these results, we conclude that induction of ROS is critical for the antiproliferative activity of CLEFMA and the Nrf2-mediated oxidative stress response fails to salvage H441 cells...
  23. pmc Cancer stem cells: a novel paradigm for cancer prevention and treatment
    Dharmalingam Subramaniam
    Medicine and Cell Biology, University of Oklahoma Health Sciences Center, 920 Stanton L Young Boulevard, WP1345, Oklahoma City, OK 73104, USA
    Mini Rev Med Chem 10:359-71. 2010
    ..Dietary phytochemicals possess anti-cancer properties and represent a promising approach for the prevention and treatment of many cancers...
  24. pmc Reg IV regulates normal intestinal and colorectal cancer cell susceptibility to radiation-induced apoptosis
    Kumar S Bishnupuri
    Division of Gastroenterology, Washington University School of Medicine, St Louis, Missouri 63110, USA
    Gastroenterology 138:616-26, 626.e1-2. 2010
    ..Human CRC cells expressing higher levels of Reg IV gene and its protein product (Reg IV) are resistant to conventional therapies, including irradiation (IR). However, the underlying mechanism is not well defined...