2.1. Glioblastoma cell source

The cell lines, U87MG (HTB‐14TM), and U251MG were obtained from the American Type Culture Collection (ATCC^®, Manassas, VA, USA). The glioblastoma stem‐like cell lines NCH421K and NCH64436 were purchased from Cell Line Services (CLS, Eppelheim, Germany). Linz1, Linz2, and Gli16 were derived from glioblastoma patients from a phase II clinical trial ({"type":"clinical-trial","attrs":{"text":"NCT01213407","term_id":"NCT01213407"}}NCT01213407) via surgery, dissociation, and subsequentin vitro culture (J. Buchroithner, F. Erhart, J. Pichler, G. Widhalm, M. Preusser, G. Stockhammer, M. Nowosielski, S. Iglseder, C.F. Freyschlag, S. Oberndorfer, K. Bordihn, G. von Campe, M. Hoffermann, R. Ruckser, K. Rössler, F. Erhart, S. Spiegl‐Kreinecker, M.B. Fischer, T. Czech, C. Visus, G. Krumpl, T. Felzmann & C. Marosi, data currently being submitted). All patients had given their written informed consent that their cell material can be processed for further studies in addition to the clinical trial. The ethics committee of the federal state of Upper Austria approved the research (approval number TRX 2/P‐II‐018).