The present study indicates that downregulation of Notch2 mRNA and protein expression suppresses U87 human glioma cell proliferation in vitro and in vivo, and induces cell cycle arrest at the G0/G1 phase by upregulation of p21 expression, and downregulation of MCM2 and cyclin-D1 expression and cell apoptosis. The gene discussed is NOTCH2; the disease is glioma.