Аннотация:Abstract: Despite multimodal approaches for the treatment of multiforme glioblastoma (GBM) advances in outcome have been very modest indicating the necessity of novel diagnostic and therapeuticstrategies. Currently, mesenchymal stem cells (MSCs) represent a promising platform for cell-basedcancer therapies because of their tumor-tropism, low immunogenicity, easy accessibility, isolationprocedure, and culturing. In the present study, we assessed the tumor-tropism and biodistributionof the superparamagnetic iron oxide nanoparticle (SPION)-labeled MSCs in the orthotopic modelof C6 glioblastoma in Wistar rats. As shown in in vitro studies employing confocal microscopy,high-content quantitative image cytometer, and xCelligence system MSCs exhibit a high migratorycapacity towards C6 glioblastoma cells. Intravenous administration of SPION-labeled MSCs in vivoresulted in intratumoral accumulation of the tagged cells in the tumor tissues that in turn significantlyenhanced the contrast of the tumor when high-field magnetic resonance imaging was performed.Subsequent biodistribution studies employing highly sensitive nonlinear magnetic response measurements (NLR-M2) supported by histological analysis confirm the retention of MSCs in the glioblastoma.In conclusion, MSCs due to their tumor-tropism could be employed as a drug-delivery platform forfuture theranostic approaches.Keywords: mesenchymal stem cells; biodistribution; nonlinear magnetic response; superparamagneticiron oxide nanoparticles; multiforme glioblastoma; C6 glioma; magnetic resonance imaging; targeteddrug delivery