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Updated: May 8, 2026
06:09
Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells
Published on: June 7, 2019
Somatic mutations in MAP3K5 attenuate its proapoptotic function in melanoma through increased binding to thioredoxin
Todd D Prickett1, Brad Zerlanko1, Jared J Gartner1
1The Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA.
The Journal of Investigative Dermatology
|September 7, 2013
Summary
Researchers discovered a new mutation in the MAP3K5 gene in melanoma patients. This mutation, R256C, may offer a new therapeutic target for advanced metastatic melanoma.
Area of Science:
- Genomics
- Oncology
- Molecular Biology
Background:
- Advanced metastatic melanoma has a poor prognosis.
- The genetic underpinnings of melanoma pathogenesis are not fully understood.
- High-throughput sequencing enables comprehensive somatic mutation discovery in cancer.
Purpose of the Study:
- To identify recurrent somatic mutations in melanoma using whole-genome and whole-exome sequencing.
- To investigate the functional impact of identified mutations.
- To explore potential therapeutic targets for melanoma.
Main Methods:
- Whole-genome and whole-exome sequencing of 29 melanoma samples.
- Prevalence screening of MAP3K5 mutations in 288 melanoma samples.
- Functional analysis of the MAP3K5 R256C mutation in melanoma cells.
Main Results:
- Identified recurrent nonsynonymous mutations in several genes, including MAP3K5.
- Found MAP3K5 R256C mutation in 5 out of 288 melanomas, exclusively in BRAF wild-type samples.
- Demonstrated that MAP3K5 R256C mutation attenuates MKK4 activation via increased thioredoxin binding, promoting melanoma cell proliferation and growth.
Conclusions:
- The MAP3K5 R256C mutation is a potential therapeutic target in melanoma.
- MAP3K5 mutations may represent an alternative pathway to BRAF mutations in melanoma.
- Understanding these genetic alterations can guide the development of novel melanoma treatments.
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