The cancer stem cell (CSC) concept has important therapeutic implications, but its investigation has been hampered both by a lack of consistency in the terms used for these cells and by how they are defined. Evidence of their heterogeneous origins, frequencies and their genomic, as well as their phenotypic and functional, properties has added to the confusion and has fuelled new ideas and controversies. Participants in The Year 2011 Working Conference on CSCs met to review these issues and to propose a conceptual and practical framework for CSC terminology. More precise reporting of the parameters that are used to identify CSCs and to attribute responses to them is also recommended as key to accelerating an understanding of their biology and developing more effective methods for their eradication in patients.
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The Year 2011 Working Conference on Cancer Stem Cells was supported by a Cancer Stem Cell Grant of the Medical University of Vienna, Austria. The authors would like to thank S. Sonnleitner and K. Krassel for their helpful technical support. H.E.J. was supported by the EU 6th FP to MSCNET (LSHC-CT-2006-037602). M.C. is supported by a Fellowship from the Scottish Funding Council (SCD/04) and J.V.M. by the NIHR Biomedical Research Centre Funding Scheme, UK.
The authors declare no competing financial interests.
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