Melanoma proteomics unravels major differences related to mutational status

Trilla-Fuertes, L.; Gamez-Pozo, A.; Prado-Vazquez, G.; Zapater-Moros, A.; Diaz-Almiron, M.; Fortes, C.; Lopez-Vacas, R.; Marquez-Rodas, I.; Soria, A.; Fresno Vara, J. A.; Espinosa, E.

doi:10.1101/198358

bioRxiv · 10.1101/198358

Melanoma proteomics unravels major differences related to mutational status

Trilla-Fuertes, L.·Gamez-Pozo, A.·Prado-Vazquez, G.·Zapater-Moros, A.·Diaz-Almiron, M.·Fortes, C.·Lopez-Vacas, R.·Marquez-Rodas, I.·Soria, A.·Fresno Vara, J. A.·Espinosa, E.

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Abstract

The aim of the study was to explore the molecular differences between melanoma tumor subtypes, based on BRAF and NRAS mutational status. Fourteen formalin-fixed, paraffin- embedded melanoma samples were analyzed using a high-throughput proteomics approach, coupled with probabilistic graphical models and Flux Balance Analysis, to characterize these differences. Proteomics analyses showed differences in expression of proteins related with fatty acid metabolism, melanogenesis and extracellular space between BRAF mutated and BRAF non-mutated melanoma tumors. Additionally, probabilistic graphical models showed differences between melanoma subgroups at biological processes such as melanogenesis or metabolism. On the other hand, Flux Balance Analysis predicts a higher tumor growth rate in BRAF mutated melanoma samples. In conclusion, differential biological processes between melanomas showing a specific mutational status can be detected using combined proteomics and computational approaches.

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Trilla-Fuertes, L., Gamez-Pozo, A., Prado-Vazquez, G., Zapater-Moros, A., Diaz-Almiron, M., Fortes, C., Lopez-Vacas, R., Marquez-Rodas, I., Soria, A., Fresno Vara, J. A., Espinosa, E.. 2017-10-06. Melanoma proteomics unravels major differences related to mutational status. https://doi.org/10.1101/198358

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