Gene expression profiling of melanoma brain metastases and matched extracranial metastases

An improved understanding of the molecular pathogenesis of brain metastases, one of the most common and devastating complications of advanced melanoma, may identify and prioritize rational therapeutic approaches for this disease. In particular, the identification of molecular differences between brain and extracranial metastases would support the need for the development of organ-specific therapeutic approaches. Hotspot mutations, copy number variations (CNV), global mRNA expression patterns, and protein expression and activation, quantitatively analyzed by molecular inversion probe arrays, microarrays and reverse phase protein array (RPPA) were evaluated in pairs of melanoma brain metastases and extracranial metastases from patients who had undergone surgical resection for both types of tumors. Seventy-two samples from 52 brain (except for patient 01, who had a spinal cord metastasis) and extracranial metastases of melanoma were analyzed. Available biological replicates (different parts of the same tumor) were included.