title: Cancer stem cells: the challenges ahead.
abstract: Cancer stem cells (CSCs) have been proposed as the driving force of tumorigenesis and the seeds of metastases. However, their existence and role remain a topic of intense debate. Recently, the identification of CSCs in endogenously developing mouse tumours has provided further support for this concept. Here I discuss the challenges in identifying CSCs, their dependency on a supportive niche and their role in metastasis, and propose that stemness is a flexible — rather than fixed — quality of tumour cells that can be lost and gained.
authors.affiliation: Laboratory for Experimental Oncology and Radiobiology, Center for Experimental Molecular Medicine, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands. j.p.medema@amc.nl
authors.forename: Jan Paul
authors.initials: JP
authors.lastname: Medema
mesh_terms: D000818:Animals; D006801:Humans; D051379:Mice; D009362:Neoplasm Metastasis; D009369:Neoplasms / Q000473:pathology*; D014411:Neoplastic Stem Cells / Q000473:pathology*
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