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Updated: Jul 6, 2026
06:09
Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells
Published on: June 7, 2019
Inducible BRAF suppression models for melanoma tumorigenesis
Klaus P Hoeflich1, Bijay Jaiswal, David P Davis
1Genentech Inc., Department of Molecular Biology, South San Francisco, CA, USA.
Methods in Enzymology
|April 1, 2008
Summary
BRAF mutations are common in melanoma and benign nevi. Despite early occurrence, BRAF is essential for melanoma growth and maintenance, requiring additional genetic changes for progression.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Somatic BRAF mutations, particularly V600E, are prevalent in 50-70% of melanomas.
- BRAF V600E mutations constitutively activate ERK signaling, promoting melanoma cell proliferation and survival.
- BRAF mutations also occur in benign nevi, suggesting they are an early event but not sufficient for melanoma development.
Purpose of the Study:
- To investigate the role of BRAF in melanoma pathogenesis and maintenance.
- To understand why BRAF mutations in benign nevi rarely lead to melanoma.
Main Methods:
- Analysis of BRAF mutation prevalence in melanoma and nevi.
- Utilizing inducible shRNA for targeted BRAF knockdown in melanoma cell lines.
- Assessing tumor growth and maintenance in xenograft models following BRAF knockdown.
Main Results:
- BRAF mutations are found in a high percentage of both melanomas and benign nevi.
- Targeted BRAF knockdown in BRAF-mutated melanoma cell lines significantly impaired tumor growth and maintenance in vivo.
- This indicates BRAF is crucial for the survival and proliferation of established melanoma.
Conclusions:
- BRAF mutations are necessary but not sufficient for melanoma progression, requiring additional genetic alterations.
- Targeting BRAF is a viable therapeutic strategy for established melanomas harboring these mutations.
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