ENO2 and melanoma: Both cell types showed negative staining for glial fibrillary acidic protein (GFAP), neuron specific enolase (NSE), HMB45, melanoma-pan, cytokeratin (CK), epithelial membrane antigen (EMA), alpha-fetoprotein (AFP), CD30, human chorion gonadotropin (HCG), SM-action, CD68, CD163, and CD34.