Brain tumor stem cells were first identified using a serum-free suspension culture method featuring supplementation with basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF)  originally used to isolate adult neural stem cells as “neurospheres” . Neurosphere culture has been shown to better preserve the genotype and phenotype of patient glioblastoma samples in comparison with adherent serum cultures, which acquired additional mutations and displayed a differentiated phenotype poorly representative of primary glioblastoma .
Culture using serum-free EGF/bFGF-supplemented media has become a common method to enrich for stem-like cells from many tumor types [4–7]. The original neural-specific media is now used as a general stem cell media (SCM), with little apparent consideration as to whether or not the factors that support neural tissue growth might have different effects on other cell lineages. Sphere culture has been used in studies examining stem cell characteristics and melanoma heterogeneity [8–10]. While they present no conclusive evidence that SCM enriches for tumorigenic melanoma cells, there is interest in the potential for SCM culture to provide a more representative model for melanoma  and other cancers. We cultured melanoma cells de novo in a consensus SCM and a standard serum-containing media and evaluated cellular function, gene expression profiles, and DNA copy number variation in reference to the original patient samples.