GFAP and neoplasm: We also observed increased abundance and intensity of glial fibrillary acidic protein (GFAP)-positive cell protrusions and infiltrates at the site of the tumor cell mass in SAG and SAG plus bFGF-treated slices; this accumulation of GFAP-positive cells was not observed in the samples treated with BGJ398 or LDE225 (Supplementary Figure S3A).