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Updated: Nov 3, 2025
07:01
An Orthotopic Mouse Model of Anaplastic Thyroid Carcinoma
Published on: April 17, 2013
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BRAF Inhibitors Induce Feedback Activation of RAS Pathway in Thyroid Cancer Cells
Elisa Bonaldi1, Chiara Gargiuli2, Loris De Cecco2
1Molecular Mechanisms Unit, Department of Research, Fondazione IRCCS Istituto Nazionale dei Tumori, 20133 Milan, Italy.
International Journal of Molecular Sciences
|June 2, 2021
Summary
BRAF inhibitors like Vemurafenib and Dabrafenib show antiproliferative and redifferentiative effects in papillary thyroid cancer (PTC) cell lines. These BRAF inhibitors also rewire the MAPK pathway, offering insights into targeted therapy response mechanisms.
Area of Science:
- Oncology
- Molecular Biology
- Endocrinology
Background:
- BRAF mutations are common in papillary thyroid cancer (PTC).
- BRAF inhibitors are used for treatment-resistant PTC, but resistance mechanisms are unclear.
- Understanding BRAF inhibitor response is crucial for optimizing targeted therapies in thyroid cancer.
Purpose of the Study:
- To investigate the effects of Vemurafenib and Dabrafenib on BRAF-mutated thyroid cancer (TC) cell lines.
- To explore the mechanisms underlying BRAF inhibitor response in TC.
- To analyze gene expression and pathway modulation following targeted therapy.
Main Methods:
- Treatment of BRAF-mutated TC cell lines with Vemurafenib and Dabrafenib.
- Assessment of cell proliferation and NIS transporter activity.
- Global gene expression analysis using microarrays and gene set enrichment analysis (GSEA).
Main Results:
- Both BRAF inhibitors demonstrated antiproliferative and redifferentiative effects on TC cells.
- Treatment led to a rewiring of the MAPK pathway, with increased RAS signaling.
- Gene expression analysis revealed modulation of pathways related to MAPK activation and thyroid differentiation.
Conclusions:
- Vemurafenib and Dabrafenib induce significant anti-cancer effects in BRAF-mutated TC.
- A MAPK pathway rewiring towards RAS signaling is a key response mechanism.
- Findings provide insights into targeted therapy response in thyroid cancer, aligning with recent clinical observations.
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