Insulin-like growth factor binding protein-2 regulates β-catenin signaling pathway in glioma cells and contributes to poor patient prognosis
| Autor: | Vani Santosh, Janhvi Jaiswal, Arivazhagan Arimappamagan, Priyanka Gokulnath, Mohsin Bashir, S D Shwetha, Paturu Kondaiah, Arun H Shastry, Shilpa Patil |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Cancer Research Integrins medicine.medical_treatment Mice Nude Biology Insulin-like growth factor-binding protein Receptor IGF Type 1 03 medical and health sciences Mice 0302 clinical medicine Downregulation and upregulation Basic and Translational Investigation Glioma Cell Line Tumor medicine Animals Humans beta Catenin Gene knockdown Glycogen Synthase Kinase 3 beta Brain Neoplasms Growth factor Receptors Somatomedin medicine.disease Prognosis Survival Analysis Insulin-Like Growth Factor Binding Protein 2 030104 developmental biology Oncology 030220 oncology & carcinogenesis Cancer research biology.protein Immunohistochemistry Heterografts Neurology (clinical) Signal transduction Stem cell Glioblastoma Signal Transduction |
| Popis: | Background. Upregulation of insulin-like growth factor binding protein 2 (IGFBP-2) is often associated with aggressiveness of glioblastoma (GBM) and contributes to poor prognosis for GBM patients. In view of the regulation of beta-catenin by IGFBP-2 in breast cancer and the crucial role of beta-catenin pathway in glioma invasion, proliferation and maintenance of glioma stem cells, the mechanism of regulation of beta-catenin by IGFBP-2, and its role in GBM prognosis was studied. Methods. Regulation of the beta-catenin pathway was studied by immunocytochemistry, Western blot analysis, luciferase assays, and real-time RT-PCR. The role of IGFBP-2 was studied by subcutaneous tumor xenografts in immunocompromised mice using glioma cells engineered to express IGFBP-2 and its domains. GBM patient tumor tissues (n = 112) were analyzed for expression of IGFBP-2 and beta-catenin by immunohistochemistry. Survival analysis was performed employing Cox regression and Kaplan-Meier survival analyses. Results. IGFBP-2 knockdown in U251, T98G, and U373 or overexpression in LN229 and U87 cells revealed a role for IGFBP-2 in stabilization of beta-catenin and regulation of its nuclear functions involving integrin-mediated inactivation of GSK3 beta. Similar results were obtained upon overexpression of the C-terminal domain of IGFBP-2 but not the N-terminal domain. Subcutaneous xenograft tumors overexpressing either full-length or the C-terminal domain of IGFBP-2 showed larger volume as compared with controls. Coexpression of high levels of IGFBP-2 and beta-catenin was associated with worse prognosis (P = .001) in GBM patients. Conclusion. IGFBP-2 potentiates GBM tumor growth by the activation of the beta-catenin pathway through its C-terminal domain, and their coexpression possibly contributes to worse patient prognosis. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|