Background: Recent evidence suggests that head and neck squamous cell carcinomas (HNSCCs) harbor a small subpopulation of highly tumorigenic cells, designated cancer stem cells. A limiting factor in cancer stem cell research is the intrinsic difficulty of expanding cells in an undifferentiated state in vitro.
Methods: Here, we describe the development of the orosphere assay, a method for the study of putative head and neck cancer stem cells. An orosphere is defined as a nonadherent colony of cells sorted from primary HNSCCs or from HNSCC cell lines and cultured in 3-dimensional soft agar or ultralow attachment plates. Aldehyde dehydrogenase activity and CD44 expression were used here as stem cell markers.
Results: This assay allowed for the propagation of head and neck cancer cells that retained stemness and self-renewal.
Conclusion: The orosphere assay is well suited for studies designed to understand the pathobiology of head and neck cancer stem cells.
Copyright © 2012 Wiley Periodicals, Inc.