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Wnt/β-catenin pathway involvement in ionizing radiation-induced invasion of U87 glioblastoma cells

Beteiligung des Wnt/β-Catenin-Signalwegs an der strahleninduzierten Invasion von U87-Glioblastomzellen

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Abstract

Background

Radiotherapy has been reported to promote the invasion of glioblastoma cells; however, the underlying mechanisms remain unclear. Here, we investigated the role of the Wnt/β-catenin pathway in radiation-induced invasion of glioblastoma cells.

Methods

U87 cells were irradiated with 3 Gy or sham irradiated in the presence or absence of the Wnt/β-catenin pathway inhibitor XAV 939. Cell invasion was determined by an xCELLigence real-time cell analyser and matrigel invasion assays. The intracellular distribution of β-catenin in U87 cells with or without irradiation was examined by immunofluorescence and Western blotting of nuclear fractions. We next investigated the effect of irradiation on Wnt/β-catenin pathway activity using TOP/FOP flash luciferase assays and quantitative polymerase chain reaction analysis of β-catenin target genes. The expression levels and activities of two target genes, matrix metalloproteinase (MMP)-2 and MMP-9, were examined further by Western blotting and zymography.

Results

U87 cell invasiveness was increased significantly by ionizing radiation. Interestingly, ionizing radiation induced nuclear translocation and accumulation of β-catenin. Moreover, we found increased β-catenin/TCF transcriptional activities, followed by up-regulation of downstream genes in the Wnt/β-catenin pathway in irradiated U87 cells. Importantly, inhibition of the Wnt/β-catenin pathway by XAV 939, which promotes degradation of β-catenin, significantly abrogated the pro-invasion effects of irradiation. Mechanistically, XAV 939 suppressed ionizing radiation-triggered up-regulation of MMP-2 and MMP-9, and inhibited the activities of these gelatinases.

Conclusion

Our data demonstrate a pivotal role of the Wnt/β-catenin pathway in ionizing radiation-induced invasion of glioblastoma cells, and suggest that targeting β-catenin is a promising therapeutic approach to overcoming glioma radioresistance.

Zusammenfassung

Hintergrund

Studien haben gezeigt, dass eine Strahlentherapie die Invasivität von Glioblastomzellen erhöht. Zwar wurden mehrere Signalwege mit diesem strahleninduzierten Eindringen in Zusammenhang gebracht, doch die genauen Mechanismen sind bisher unklar. In der vorliegenden Studie wurden die proinvasive Wirkung einer Bestrahlung auf U87-Zellen überprüft und die Beteiligung des Wnt/ß-Catenin-Signalwegs als möglicher zugrundeliegender Mechanismus diskutiert.

Methoden

U87-Zellen wurden einer Strahlung von 3 Gy oder einer Scheinbestrahlung ausgesetzt, einige Zellen waren zuvor mit dem Wnt/ß-Catenin-Inhibitor XAV 939 behandelt worden. Der Einfluss dieser verschiedenen Konditionen auf die Invasivität wurde anschließend mit dem xCELLigence Zellanalysesystems und einem Matrigel-Invasion-Assay überprüft. Die intrazelluläre ß-Catenin-Verteilung mit bzw. ohne Bestrahlung wurde anhand von Western-Blot-Analysen unterschiedlicher Kernfraktionen und Immunfluoreszenzanalysen untersucht, die Wirkung der Strahlung auf die Aktivität des Wnt/ß-Catenin-Signalwegs durch einen Luciferase-Assay. Die Expressionslevel und Aktivität von Zielgenen, wie MMP-2 und MMP-9, wurden durch eine Western-Blot-Analyse und einen Zymographie-Assay determiniert.

Ergebnisse

Die Invasivität von U87-Zellen wurde durch ionisierende Strahlung signifikant erhöht. Immunfluoreszenzanalysen zeigten eine strahleninduzierte nukleäre Translokation und eine ß-Catenin-Akkumulation. Nach Bestrahlung zeigten sich im Luciferase-Assay zudem eine erhöhte ß-Catenin/TCF-Transkriptionsaktivität, gefolgt von einer Hochregulation der Downstream-Zielgene in den Wnt/ß-Catenin-Signalwegen in bestrahlten U87-Zellen. XV 939 unterdrückte die strahleninduzierte Hochregulierung von MMP-2 und -9 und inhibierte die Aktivität dieser Gelatinasen.

Fazit

Die vorgestellten Daten zeigen die zentrale Rolle des Wnt/ß-Catenin-Signalwegs für die strahleninduzierte Erhöhung der Invasivität von Glioblastomzellen. In diesem Zusammenhang könnte die Inhibierung von ß-Catenin einen viel versprechenden Ansatz in der Behandlung strahlenresistenter Gliome darstellen.

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References

  1. Gralow J, Ozols RF, Bajorin DF et al (2008) Clinical cancer advances 2007: major research advances in cancer treatment, prevention, and screening–a report from the American society of clinical oncology. J Clin Oncol 26:313–325

    Article  PubMed  Google Scholar 

  2. Stupp R, Mason WP, van den Bent MJ et al (2005) Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma. N Engl J Med 352:987–996

    Article  CAS  PubMed  Google Scholar 

  3. Gerstein J, Franz K, Steinbach JP et al (2010) Postoperative radiotherapy and concomitant temozolomide for elderly patients with glioblastoma. Radiother Oncol 97:382–386

    Article  CAS  PubMed  Google Scholar 

  4. Gladstone M, Su TT (2012) Radiation responses and resistance. Int Rev Cell Mol Biol 299:235–253

    Article  CAS  PubMed  Google Scholar 

  5. Cheng JC, Chou CH, Kuo ML et al (2006) Radiation-enhanced hepatocellular carcinoma cell invasion with MMP-9 expression through PI3K/Akt/NF-kappaB signal transduction pathway. Oncogene 25:7009–7018

    Article  CAS  PubMed  Google Scholar 

  6. De Bacco F, Luraghi P, Medico E et al (2011) Induction of MET by ionizing radiation and its role in radioresistance and invasive growth of cancer. J Natl Cancer Inst 103:645–661

    Article  CAS  PubMed  Google Scholar 

  7. Madani I, De Neve W, Mareel M (2008) Does ionizing radiation stimulate cancer invasion and metastasis? Bull Cancer 95:292–300

    CAS  PubMed  Google Scholar 

  8. Fujita M, Otsuka Y, Yamada S et al (2011) X-ray irradiation and Rho-kinase inhibitor additively induce invasiveness of the cells of the pancreatic cancer line, MIAPaCa-2, which exhibits mesenchymal and amoeboid motility. Cancer Sci 102:792–798

    Article  CAS  PubMed  Google Scholar 

  9. Wild-Bode C, Weller M, Rimner A et al (2001) Sublethal irradiation promotes migration and invasiveness of glioma cells: implications for radiotherapy of human glioblastoma. Cancer Res 61:2744–2750

    CAS  PubMed  Google Scholar 

  10. Gliemroth J, Feyerabend T, Gerlach C et al (2003) Proliferation, migration, and invasion of human glioma cells exposed to fractionated radiotherapy in vitro. Neurosurg Rev 26:198–205

    Article  PubMed  Google Scholar 

  11. Zhai GG, Malhotra R, Delaney M et al (2006) Radiation enhances the invasive potential of primary glioblastoma cells via activation of the Rho signaling pathway. J Neurooncol 76:227–237

    Article  CAS  PubMed  Google Scholar 

  12. Moncharmont C, Levy A, Guy JB et al (2014) Radiation-enhanced cell migration/invasion process: a review. Crit Rev Oncol Hematol 92:133–142

  13. Scrace S, O’Neill E, Hammond EM et al (2013) Use of the xCELLigence system for real-time analysis of changes in cellular motility and adhesion in physiological conditions. Methods Mol Biol 1046:295–306

    Article  PubMed  Google Scholar 

  14. Teng Y, Wang X, Wang Y et al (2010) Wnt/beta-catenin signaling regulates cancer stem cells in lung cancer A549 cells. Biochem Biophys Res Commun 392:373–379

    Article  CAS  PubMed  Google Scholar 

  15. Vermeulen L, De Sousa EMF, van der Heijden M et al (2010) Wnt activity defines colon cancer stem cells and is regulated by the microenvironment. Nat Cell Biol 12:468–476

    Article  CAS  PubMed  Google Scholar 

  16. King TD, Suto MJ, Li Y (2012) The Wnt/beta-catenin signaling pathway: a potential therapeutic target in the treatment of triple negative breast cancer. J Cell Biochem 113:13–18

    Article  CAS  PubMed  Google Scholar 

  17. Yamashita T, Ji J, Budhu A et al (2009) EpCAM-positive hepatocellular carcinoma cells are tumor-initiating cells with stem/progenitor cell features. Gastroenterology 136:1012–1024

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  18. Pala A, Karpel-Massler G, Kast RE et al (2012) Epidermal to mesenchymal transition and failure of EGFR-targeted therapy in glioblastoma. Cancers (Basel) 4:523–530

    Article  CAS  Google Scholar 

  19. Kim Y, Kim KH, Lee J et al (2012) Wnt activation is implicated in glioblastoma radioresistance. Lab Invest 92:466–473

    Article  CAS  PubMed  Google Scholar 

  20. Jin X, Jeon HY, Joo KM et al (2011) Frizzled 4 regulates stemness and invasiveness of migrating glioma cells established by serial intracranial transplantation. Cancer Res 71:3066–3075

    Article  CAS  PubMed  Google Scholar 

  21. Zheng H, Ying H, Wiedemeyer R et al (2010) PLAGL2 regulates Wnt signaling to impede differentiation in neural stem cells and gliomas. Cancer Cell 17:497–509

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  22. Kil WJ, Tofilon PJ, Camphausen K (2012) Post-radiation increase in VEGF enhances glioma cell motility in vitro. Radiat Oncol 7:25

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  23. Timke C, Zieher H, Roth A et al (2008) Combination of vascular endothelial growth factor receptor/platelet-derived growth factor receptor inhibition markedly improves radiation tumor therapy. Clin Cancer Res 14:2210–2219

    Article  CAS  PubMed  Google Scholar 

  24. Park CM, Park MJ, Kwak HJ et al (2006) Ionizing radiation enhances matrix metalloproteinase-2 secretion and invasion of glioma cells through Src/epidermal growth factor receptor-mediated p38/Akt and phosphatidylinositol 3-kinase/Akt signaling pathways. Cancer Res 66:8511–8519

    Article  CAS  PubMed  Google Scholar 

  25. Ji H, Wang J, Nika H et al (2009) EGF-induced ERK activation promotes CK2-mediated disassociation of alpha-Catenin from beta-Catenin and transactivation of beta-Catenin. Mol Cell 36:547–559

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  26. Zhou BP, Deng J, Xia W et al (2004) Dual regulation of Snail by GSK-3beta-mediated phosphorylation in control of epithelial-mesenchymal transition. Nat Cell Biol 6:931–940

    Article  CAS  PubMed  Google Scholar 

  27. Luu H, Zhang R, Haydon R et al (2004) Wnt/β-catenin signaling pathway as novel cancer drug targets. Current Cancer Drug Targets 4:653–671

    Article  CAS  PubMed  Google Scholar 

  28. Wu B, Crampton SP, Hughes CC (2007) Wnt signaling induces matrix metalloproteinase expression and regulates T cell transmigration. Immunity 26:227–239

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  29. King TD, Zhang W, Suto MJ et al (2012) Frizzled7 as an emerging target for cancer therapy. Cell Signal 24:846–851

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  30. MacDonald BT, Tamai K, He X (2009) Wnt/beta-catenin signaling: components, mechanisms, and diseases. Dev Cell 17:9–26

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  31. Wick W, Platten M, Weller M (2001) Glioma cell invasion: regulation of metalloproteinase activity by TGF-beta. J Neurooncol 53:177–185

    Article  CAS  PubMed  Google Scholar 

  32. Platten M, Wick W, Weller M (2001) Malignant glioma biology: role for TGF-beta in growth, motility, angiogenesis, and immune escape. Microsc Res Tech 52:401–410

    Article  CAS  PubMed  Google Scholar 

  33. Huang SM, Mishina YM, Liu S, et al (2009) Tankyrase inhibition stabilizes axin and antagonizes Wnt signalling. Nature 461:614–620

    Article  CAS  PubMed  Google Scholar 

  34. Fancy SP, Harrington EP, Yuen TJ et al (2011) Axin2 as regulatory and therapeutic target in newborn brain injury and remyelination. Nat Neurosci 14:1009–1016

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  35. Zhao JW, Dyson SC, Kriegel C, et al (2014) Modelling of a targeted nanotherapeutic ‘stromaʼ to deliver the cytokine LIF, or XAV939, a potent inhibitor of Wnt-beta-catenin signalling, for use in human fetal dopaminergic grafts in Parkinsonʼs disease. Dis Model Mech 7:1193–1203

    Article  PubMed Central  PubMed  Google Scholar 

  36. Barker N, Clevers H (2006) Mining the Wnt pathway for cancer therapeutics. Nat Rev Drug Discov 5:997–1014

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

This research was in part supported by a grant from the National Natural Sciences Foundation of China (No. 81272780). We gratefully thank Dr. Fengjuan Fan and Dr. Anna-Lena Scherr, Centrum für Tumorerkrankungen, Heidelberg, Germany, for help with the manuscript. Authorsʼ contributions: Z.D. cultured the U87 cells and conducted RTCA and matrigel invasion assay, participated in real-time quantitative PCR and drafted the manuscript. L.Z. carried out the immunofluorescence staining and colocalization analysis. N.H. participated in the zymography and immunoblotting. M.Z. participated in the design of the study and performed the statistical analysis. X.L. conceived of the study, and participated in its design and coordination and prepared the final manuscript. All authors read and approved the final manuscript.

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Correspondence to Xiaojuan Lyu MD.

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Z. Dong, L. Zhou, N. Han, M. Zhang, and X. Lyu state that there are no conflicts of interest. The accompanying manuscript does not include studies on humans or animals.

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Dong, Z., Zhou, L., Han, N. et al. Wnt/β-catenin pathway involvement in ionizing radiation-induced invasion of U87 glioblastoma cells. Strahlenther Onkol 191, 672–680 (2015). https://doi.org/10.1007/s00066-015-0858-7

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  • DOI: https://doi.org/10.1007/s00066-015-0858-7

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