Endothelial Interleukin‐6 Defines the Tumorigenic Potential of Primary Human Cancer Stem Cells. (November 2014)

• Record Type: Journal Article
• Authors: Krishnamurthy, Sudha; Warner, Kristy A.; Dong, Zhihong; Imai, Atsushi; Nör, Carolina; Ward, Brent B.; Helman, Joseph I.; Taichman, Russell S.; Bellile, Emily L.; McCauley, Laurie K.; Polverini, Peter J.; Prince, Mark E.; Wicha, Max S.; Nör, Jacques E.
• Is Part Of: Stem cells. Volume 32:Number 11(2014:Nov.)
• Page Start: 2845
• Page End: 2857
• Publication Date: 2014-11
• Subjects: Cloning -- Periodicals; Clone cells -- Periodicals; Stem cells -- Periodicals; Cell Differentiation -- Periodicals; Cell Division -- Periodicals; Clone Cells -- Periodicals; Hematopoietic Stem Cells -- Periodicals; Stem Cells -- Periodicals; 571.84
• DOI: 10.1002/stem.1793
• Languages: English
• ISSNs: 1066-5099

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Head and neck squamous cell carcinomas (HNSCC) contain a small subpopulation of stem cells endowed with unique capacity to generate tumors. These cancer stem cells (CSC) are localized in perivascular niches and rely on crosstalk with endothelial cells for survival and self‐renewal, but the mechanisms involved are unknown. Here, we report that stromal interleukin (IL)−6 defines the tumorigenic capacity of CSC sorted from primary human HNSCC and transplanted into mice. In search for the cellular source of Interleukin‐6 (IL‐6), we observed a direct correlation between IL‐6 levels in tumor‐associated endothelial cells and the tumorigenicity of CSC. In vitro, endothelial cell‐IL‐6 enhanced orosphere formation, p‐STAT3 activation, survival, and self‐renewal of human CSC. Notably, a humanized anti‐IL‐6R antibody (tocilizumab) inhibited primary human CSC‐mediated tumor initiation. Collectively, these data demonstrate that endothelial cell‐secreted IL‐6 defines the tumorigenic potential of CSC, and suggest that HNSCC patients might benefit from therapeutic inhibition of IL‐6/IL‐6R signaling. S<sc>tem</sc> C<sc>ells</sc><italic>2014;32:2845–2857</italic></p> </abstract>