HEY1 and glioblastoma: Hulleman et al. [6] found that the transcription factor HEY1, a downstream target molecule of the Notch signaling pathway, was significantly upregulated in gastric cancer and that HEY1 expression in glioblastoma multiforme correlated with tumor grade and survival, and that silencing HEY1 by RNA interference technology would cause glioblastoma in tissue culture to diminished proliferation.