1. ¹Department of Biotechnology and Biosciences, University of Milan-Bicocca, Milan, Italy
2. ²Unit of Cancer Stem Cell Biology, StemGen Spa, University of Milan–Bicocca, Milan, Italy
3. ³Department of Neurosciences and Biomedical Technologies, University of Milan-Bicocca, Monza (Mi), Italy
4. ⁴Department of Neurological Sciences, Institute of Neurosurgery, Catholic University of the Sacred Heart, Rome, Italy
5. ⁵Department of Neurosurgery, National Neurological Institute 'C Besta', Milan, Italy
6. ⁶Department of Neurological Surgery, Johns Hopkins Medical School, Baltimore, MD, USA

Correspondence: Professor L Dalprà, Department of Neurosciences and Biomedical Technologies, University of Milan-Bicocca, 20052 Monza (Mi), Italy. E-mail: leda.dalpra@unimib.it; Professor AL Vescovi, Department of Biotechnology and Biosciences, University of Milan-Bicocca, Piazza della Scienza 2, Milan, Lombardia 20126, Italy. E-mail: vescovi@tin.it

Received 21 July 2008; Revised 18 December 2008; Accepted 28 January 2009; Published online 16 March 2009.

Abstract

Glioblastomas (GBMs) contain transformed, self-maintaining, multipotent, tumour-initiating cancer stem cells, whose identification has radically changed our perspective on the physiology of these tumours. Currently, it is unknown whether multiple types of transformed precursors, which display alternative sets of the complement of properties of true cancer stem cells, can be found in a GBM. If different subsets of such cancer stem-like cells (CSCs) do exist, they might represent distinct cell targets, with a differential therapeutic importance, also depending on their characteristics and lineage relationship. Here, we report the presence of two types of CSCs within different regions of the same human GBM. Cytogenetic and molecular analysis shows that the two types of CSCs bear quite diverse tumorigenic potential and distinct genetic anomalies, and, yet, derive from common ancestor cells. This provides critical information to unravel the development of CSCs and the key molecular/genetic components underpinning tumorigenicity in human GBMs.