Tumor stem cells, notch, and the news

Abstract

As we prepared to put this issue of Neuro-Oncology to bed, we noted with interest that the topic of our review article this month, Notch signaling in human gliomas, is also in the news. In our case, we are running a review titled “The functional role of Notch signaling in human gliomas,” by Stockhausen et al. (see page 199–211).1 In this review, the authors look at the “interplay” between Notch signaling in normal glial development and processes known to be involved in the development of malignant tumors (for instance, hypoxia and angiogenesis). In particular, they look at the roles of Notch in normal neural stem cells and brain cancer stem cells, the latter of which represent a formidable therapeutic challenge (as stem cells do in all cancers2). As Stockhausen et al. point out, therapies that can act at the stem cell level may offer the promise of overcoming gliomas' characteristic resistance to therapy and the consequently poor outcomes the patients face. The authors discuss several approaches of recent interest, including the use of gamma-secretase inhibitors to overcome the Notch signal. In the news, meanwhile, appeared an announcement from Duke University that the journal Stem Cells had posted a prepublication version of an article detailing Notch's contribution to the radioresistance of glioma stem cells and the use of gamma-secretase inhibitors to overcome that problem.3 This example demonstrates the complexity of tumor progression and tumor cell differentiation and the necessity to better understand the multiple molecular signaling networks that exert control in this process.