Objectives: Notch signaling plays a complex role in human malignancy. It can affect cell proliferation, differentiation, and apoptosis either positively or negatively, depending on cell type.
Methods: Clinical gliomas from 274 patients who had not received chemotherapy were collected, and the expression of Notch1 protein was assessed by immunochemistry assays. Staining evaluation results were analyzed statistically in relation to various clinicopathological characters. Kaplan-Meier and Cox proportional hazards regression methods were used to assess associations of Notch1 expression with glioma survival.
Results: We found that the levels of expression of Notch1 protein were higher in glioma than control normal brain tissue. Moreover, the expression of Notch1 was associated closely with glioma progression, since expression levels increased from grades I to IV glioma. The overall survival rate was significantly lower for patients with Notch1 positive than those with Notch1 negative tumors. Multivariate analysis showed that Notch1 was an independent prognostic factor for patients with glioma.
Conclusions: These findings we confirm that Notch1 expression is up-regulated in glioma and related to tumor progression. Notch1 might also serve as a novel prognostic marker that is independent of, and additive to, the WHO grade.
Copyright © 2011 Wiley-Liss, Inc.