1. BRAF Inhibitors Induce Feedback Activation of RAS Pathway in Thyroid Cancer Cells
- Author
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Loris De Cecco, Elisa Bonaldi, Emanuela Minna, Arianna Micali, Angela Greco, Maria Grazia Rizzetti, Maria Grazia Borrello, and Chiara Gargiuli
- Subjects
MAPK/ERK pathway ,endocrine system diseases ,Papillary thyroid cancer ,Biology (General) ,Vemurafenib ,Thyroid cancer ,Spectroscopy ,BRAFV600E ,Thyroid ,BRAF inhibitors ,General Medicine ,Computer Science Applications ,Gene Expression Regulation, Neoplastic ,Chemistry ,medicine.anatomical_structure ,thyroid cancer cell ,Thyroid function ,medicine.drug ,Signal Transduction ,Proto-Oncogene Proteins B-raf ,QH301-705.5 ,Context (language use) ,Catalysis ,Article ,Inorganic Chemistry ,Cell Line, Tumor ,medicine ,Biomarkers, Tumor ,Humans ,cell signaling ,Thyroid Neoplasms ,Physical and Theoretical Chemistry ,Molecular Biology ,Protein Kinase Inhibitors ,neoplasms ,QD1-999 ,Dose-Response Relationship, Drug ,business.industry ,Gene Expression Profiling ,Organic Chemistry ,Computational Biology ,Dabrafenib ,medicine.disease ,digestive system diseases ,Drug Resistance, Neoplasm ,Mutation ,Cancer research ,ras Proteins ,business ,Transcriptome - Abstract
BRAFV600E is the most frequent oncogenic mutation identified in papillary thyroid cancer (PTC). In PTC patients who do not respond to standard treatment, BRAF inhibitors are currently tested as alternative strategies. However, as observed for other targeted therapies, patients eventually develop drug resistance. The mechanisms of BRAF inhibitors response are still poorly understood in a thyroid cancer (TC) context. In this study, we investigated in BRAFV600E mutated TC cell lines the effects of Vemurafenib and Dabrafenib, two BRAF inhibitors currently used in a clinical setting. We assessed cell proliferation, and the expression and activity of the thyroid function related transporter NIS following the treatment with BRAF inhibitors. In addition, we investigated the global gene expression by microarray, the relevant modulated biological processes by gene set enrichment analysis (GSEA), and TC specific gene signatures related to MAPK pathway activation, thyroid differentiation, and transcriptional profile associated with BRAFV600E or RAS mutation. We found that both inhibitors induce antiproliferative and redifferentiative effects on TC cells, as well as a rewiring of the MAPK pathway related to RAS signaling. Our results suggest a possible mechanism of drug response to the BRAF inhibitors Vemurafenib or Dabrafenib, supporting very recent findings in TC patients treated with targeted therapies.
- Published
- 2021