Cancer stem cells from human glioblastoma resemble but do not mimic original tumors after <i>in vitro</i> passaging in serum-free media

Abstract

// Noem&iacute; Garc&iacute;a-Romero 1, * , Carmen Gonz&aacute;lez-Tejedo 2, * , Josefa Carri&oacute;n-Navarro 3, * , Susana Esteban-Rubio 4 , Gorjana Rackov 1 , Vanessa Rodr&iacute;guez-Fanjul 1 , Jorge Oliver-De La Cruz 5 , Ricardo Prat-Ac&iacute;n 6 , Mar&iacute;a Peris-Celda 6 , David Blesa 7 , Laura Ram&iacute;rez-Jim&eacute;nez 7 , Pilar S&aacute;nchez-G&oacute;mez 8 , Rosario Perona 9 , Carmen Escobedo-Lucea 10 , Cristobal Belda-Iniesta 3 , Angel Ayuso-Sacido 1, 3, 4 1 Instituto Madrile&ntilde;o de Estudios Avanzados, IMDEA Nanociencia, Madrid, Spain 2 Centro Nacional de Biotecnolog&iacute;a (CNB-CSIC), Madrid, Spain 3 Fundaci&oacute;n de Investigaci&oacute;n HM Hospitales, HM Hospitales, Madrid, Spain 4 Instituto de Medicina Molecular Aplicada (IMMA), School of Medicine, San Pablo-CEU University, Campus de Montepr&iacute;ncipe, Madrid, Spain 5 International Clinical Research Center, Center for Translational Medicine, St. Anne&rsquo;s University Hospital, Brno, Czech Republic 6 Neurosurgery Department, Hospital Universitario la Fe de Valencia, Valencia, Spain 7 Genetic and Genomic Unit, Fundaci&oacute;n Centro de Investigaci&oacute;n Pr&iacute;ncipe Felipe, Valencia, Spain 8 Neuro-oncology Unit, Instituto de Salud Carlos III-UFIEC, Madrid, Spain 9 Instituto de Investigaciones Biom&eacute;dicas, CIBERER, CSIC/UAM, Madrid, Spain 10 Division of Biopharmaceutics and Pharmacokinetics, University of Helsinki, Helsinki, Finland * These authors have contributed equally to this work Correspondence to: Angel Ayuso-Sacido, email: ayusosacido@gmail.com Keywords: cancer stem cells, glioblastoma, genetic alterations, drug discovery, primary cell culture Received: May 30, 2016&emsp;&emsp;&emsp;&emsp; Accepted: August 17, 2016&emsp;&emsp;&emsp;&emsp; Published: August 29, 2016 ABSTRACT Human gliomas harbour cancer stem cells (CSCs) that evolve along the course of the disease, forming highly heterogeneous subpopulations within the tumour mass. These cells possess self-renewal properties and appear to contribute to tumour initiation, metastasis and resistance to therapy. CSC cultures isolated from surgical samples are considered the best preclinical in vitro model for primary human gliomas. However, it is not yet well characterized to which extent their biological and functional properties change during in vitro passaging in the serum-free culture conditions. Here, we demonstrate that our CSC-enriched cultures harboured from one to several CSC clones from the human glioma sample. When xenotransplanted into mouse brain, these cells generated tumours that reproduced at least three different dissemination patterns found in original tumours. Along the passages in culture, CSCs displayed increased expression of stem cell markers, different ratios of chromosomal instability events, and a varied response to drug treatment. Our findings highlight the need for better characterization of CSC-enriched cultures in the context of their evolution in vitro, in order to uncover their full potential as preclinical models in the studies aimed at identifying molecular biomarkers and developing new therapeutic approaches of human gliomas.