Glioblastomas are lethal cancers characterized by florid angiogenesis promoted in part by glioma stem cells (GSCs). Because hypoxia regulates angiogenesis, we examined hypoxic responses in GSCs. We now demonstrate that hypoxia-inducible factor HIF2alpha and multiple HIF-regulated genes are preferentially expressed in GSCs in comparison to non-stem tumor cells and normal neural progenitors. In tumor specimens, HIF2alpha colocalizes with cancer stem cell markers. Targeting HIFs in GSCs inhibits self-renewal, proliferation, and survival in vitro, and attenuates tumor initiation potential of GSCs in vivo. Analysis of a molecular database reveals that HIF2A expression correlates with poor glioma patient survival. Our results demonstrate that GSCs differentially respond to hypoxia with distinct HIF induction patterns, and HIF2alpha might represent a promising target for antiglioblastoma therapies.
Wednesday, June 24, 2009
Hypoxic responses in glioma stem cells
Hypoxia-inducible factors regulate tumorigenic capacity of glioma stem cells by Zhizhong Li and 11 co-authors, including Jeremy N Rich, Cancer Cell 2009(Jun 2); 15(6): 501-13 [FriendFeed entry] PubMed Abstract:
Subscribe to:
Post Comments (Atom)
Posts
I wonder, how can cancer cells be stem cells? A cancer cell, by definition, is genetically unstable. A stem cell should be able to renew itself by definition. How can something renew itself if it is genetically unstable?
ReplyDeleteRecommended reading: Stem cell concepts renew cancer research by John Dick [Blood, 2008(Dec 15); 112(13): 4793-4807. The full text is publicly accessible]. Excerpt: "Because the lifespan of non–stem cells may be transient, any genetic alteration in their makeup may not persist long enough to acquire additional genetic events that are needed for full transformation, unless the initial event endows the non-stem cell with self-renewal capacity."
ReplyDelete