As a result, 20 genes (CALB1, CDC20, CDCA8, CDK1, CEP55, DLGAP5, KIF20A, KIF4A, NDC80, PBK, RRM2, SYN1, SYP, SYT1, TPX2, TTK, VEGFA, BDNF, GNG3, and TOP2A) were found as hub genes via CytoHubba in Cytoscape and functioned mainly by participating in cell cycle and p53 signaling pathway; among them, RRM2 and CEP55 were considered to have relationship with the prognosis of glioblastoma, especially RRM2.
We demonstrated for the first time that temozolomide is also a TOP2A inhibitor and established that TOP2A transcript levels determine the chemosensitivity of glioblastoma to temozolomide therapy.
We observed the expression differences of Topo-IIα gene transcript in CSCs and non-CSCs in glioblastoma cell line U87 by quantitative real-time PCR and western blot; we silenced Topo-IIα expression in U87 CSCs using Topo-IIα-specific siRNA to investigate the role of Topo-IIα in cell proliferation, cell cycle, and apoptosis.