HES1 and glioblastoma: In some cases, the net effect of Resveratrol does not allow the determination of its mechanism of action as an activator/inhibitor of Notch signaling, as was the case with Glioblastoma multiforme (GBM) cell lines U87MG and T98G, in which a simultaneous decrease in NOTCH1 and NICD expression and an increase in HES1 expression was observed [155].