P08.16 ATF3 reduces migration capacity by regulation of matrix metalloproteinases in glioblastoma in vitro
| Autor: | Astrid Weyerbrock, Jessica Guenzle, Jonathan M Goeldner |
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| Rok vydání: | 2017 |
| Předmět: | |
| Zdroj: | Neuro-Oncology. 19:iii57-iii57 |
| ISSN: | 1523-5866 1522-8517 |
| Popis: | Objective: Glioblastoma is associated with poor survival and a high recurrence rate in patients due to the inevitable uncontrolled infiltrative tumor growth. The elucidation of the molecular mechanisms may offer opportunities to prevent relapses. In this study we investigated the role of the activating transcription factor 3 (ATF3) in the context of experimental nitric oxide donor (NO) treatment with JS-K (O2-(2,4-dinitrophenyl) 1-[(4-ethoxycarbonyl)piperazin- 1-yl]diazen-1-ium-1,2-diolate) on migration of GBM cells in vitro. Methods: RNA microarray was performed to identify ATF3 as one of the genes upregulated by experimental NO therapy in U87 glioma cells. To elucidate its role in tumor growth and treatment response of malignant gliomas, ATF3 was overexpressed by lentiviral transduction and expression of target genes STAT3 and NFκB was investigated by qRT-PCR, Western Blot and immunocytochemistry. The underlying molecular mechanisms of migration capacity and proliferation were studied by Western Blot, zymography, immunostaining and PCR while migration was assessed by wound closure and invasion assay. Results: RNA microarray revealed that gene expression of ATF3 is 15-fold upregulated after exposure to 15 µM JS-K for 48 h. We demonstrate that ATF3 is directly involved in the regulation of matrix metalloproteinase expression and activation. MMP2, 7 and 9 were downregulated and MMP2 activity was reduced by overexpression of ATF3. While stat3 was 2.5-fold upregulated in cells overexpressing ATF3, STAT3 was no longer phosphorylated. Even if the expression of nfκb is not affected by ATF3, NFκB accumulated in the cytoplasm and did not translocate by TNFα stimulation. Cells overexpressing ATF3 migrated 40% slower into the gap (p=0.02) and reduced invasive capability to 30% (p=0.00004). The proliferation rate was 2-fold reduced by ATF3 (p=0.003) after 72 h whereas the influence of NO on viability did not change. Conclusions: Overexpression of ATF3 leads to a significantly reduced migration and invasion capacity by induction of tissue inhibitors of matrix metalloproteinases. ATF3 is directly involved in expression and activation of MMPs as well as the oncogenic regulators STAT3 and NFκB. Our study highlights for the first time ATF3 as a potential novel therapeutic target and can therefore be important for specific anticancer therapy to overcome the high treatment resistance of glioblastoma. |
| Databáze: | OpenAIRE |
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