% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Usta:156979, author = {D. Usta$^*$ and R. Sigaud$^*$ and J. L. Buhl$^*$ and F. Selt$^*$ and V. Marquardt$^*$ and D. Pauck$^*$ and J. Jansen and S. Pusch$^*$ and J. Ecker$^*$ and T. Hielscher$^*$ and J. Vollmer$^*$ and A. C. Sommerkamp$^*$ and T. Rubner$^*$ and D. Hargrave and C. M. van Tilburg$^*$ and S. M. Pfister$^*$ and D. T. W. Jones$^*$ and M. Remke$^*$ and T. Brummer and O. Witt$^*$ and T. Milde$^*$}, title = {{A} cell-based {MAPK} reporter assay reveals synergistic {MAPK} pathway activity suppression by {MAPK} inhibitor combination in {BRAF}-driven pediatric low-grade glioma cells.}, journal = {Molecular cancer therapeutics}, volume = {19}, number = {8}, issn = {1538-8514}, address = {Philadelphia, Pa.}, publisher = {AACR}, reportid = {DKFZ-2020-01284}, pages = {1736-1750}, year = {2020}, note = {2020 Aug;19(8):1736-1750#EA:B310#LA:B310#}, abstract = {Pilocytic astrocytomas (PAs) as well as other pediatric low-grade gliomas (pLGGs) exhibit genetic events leading to aberrant activation of the MAPK pathway. The most common alterations are KIAA1549:BRAF fusions, BRAFV600E and NF1 mutations. Novel drugs targeting the MAPK pathway (MAPKi) are prime candidates for the treatment of these single-pathway diseases. We aimed to develop an assay suitable for pre-clinical testing of MAPKi in pLGGs with the goal to identify novel MAPK pathway suppressing synergistic drug combinations. A reporter plasmid (pDIPZ) with a MAPK-responsive ELK-1-binding element driving the expression of destabilized firefly luciferase was generated and packaged using a lentiviral vector system. Pediatric glioma cell lines with a BRAF fusion (DKFZ-BT66) and a BRAFV600E mutation (BT-40) background, respectively, were stably transfected. Modulation of the MAPK pathway activity by MAPKi was measured using the luciferase reporter and validated by detection of phosphorylated protein levels. A screen of a MAPKi library was performed and synergy of selected combinations was calculated. Screening of a MAPKi library revealed MEK inhibitors as the class inhibiting the pathway with the lowest IC50s, followed by ERK and next-generation RAF inhibitors. Combination treatments with different MAPKi classes showed synergistic effects in BRAF fusion as well as BRAFV600E mutation backgrounds. We here report a novel reporter assay for medium- to high-throughput pre-clinical drug testing in pLGG cell lines. The assay confirmed MEK, ERK and next-generation RAF inhibitors as potential treatment approaches for KIAA1549:BRAF and BRAFV600E mutated pLGGs. In addition, the assay revealed that combination treatments synergistically suppressed MAPK pathway activity.}, cin = {B310 / HD01 / ED01 / FR01 / B300 / C060 / B360 / W220 / B062}, ddc = {570}, cid = {I:(DE-He78)B310-20160331 / I:(DE-He78)HD01-20160331 / I:(DE-He78)ED01-20160331 / I:(DE-He78)FR01-20160331 / I:(DE-He78)B300-20160331 / I:(DE-He78)C060-20160331 / I:(DE-He78)B360-20160331 / I:(DE-He78)W220-20160331 / I:(DE-He78)B062-20160331}, pnm = {312 - Functional and structural genomics (POF3-312)}, pid = {G:(DE-HGF)POF3-312}, typ = {PUB:(DE-HGF)16}, pubmed = {pmid:32451331}, doi = {10.1158/1535-7163.MCT-19-1021}, url = {https://inrepo02.dkfz.de/record/156979}, }