Introduction: Glioblastoma multiforme (GBM) is the most often occuring intracranial malignity of astrocyte origin in adults. This tumor disease is characterized by infaust prognosis, which is primarily caused by resistance to the therapy and early relapses relate to the presence of glioblastoma stem cells (GSCs). Targeting of GSCs could be a novel promising therapeutic approach leading to the overcome of therapy resistance and better prognosis of GBM patients. One of the approaches how to successfully regulate GSC is a targeted regulation of microRNAs (miRNAs). These small non-coding RNA molecules post-transcriptionally regulate an expression of more than 2/3 of all human genes that are also involved in stem cell associated signaling pathways.
Methods: We have prepared ten Sox-2 high- and low-expressing paired primary GBM cell lines, which have been cultured under non-serum and serum conditions, respectively. The global miRNA expression analysis was performed using GeneChip miRNA 4.0 Array (Affymetrix). Sox-2 and nestin expressions were analyzed on both protein and transcriptional levels using combination of PAGE with Western blotting and real-time PCR, respectively. Targeted regulation of miRNA levels have been carried out by the transient transfection of specific anti-miRNAs or miRNA mimics in GSC cell lines NCH 601 acquired from Interdisciplinary Center For Neurosciences (Heidelberg, Germany). The sphere formation assays are analyzed using IncuCyte ZOOM instrument (Essen BioScience).
Results: Analyze of Sox-2 positive and negative paired GBM cell lines revealed 29 differentially expressed miRNAs, from which miR-93-3p, miR-95-5p, miR-106b-5p, miR-22-3p, and miR-3195 showed high significance (adjust. P value < 0.05) and association with both Sox-2 (Spearman R; p < 0.002) and nestin (Spearman R; p < 0.02) expressions. MiR-22-3p and miR-3195 showed lower whereas other miRNAs higher expression in Sox-2 positive GBM cells.
Conclusions: Our data suggest that these miRNAs are probably involved in GSC biology maintaining and, thus, are analyzed in vitro to be promising molecular targets to overcome GBM therapeutic resistance at this time. Results of in vitro analyses will be presented. This work was supported by grants of Internal Grant Agency of the Czech Ministry of Health no. NT13514-4/2012, 15-33158A; and project "CEITEC - Central European Institute of Technology" (CZ.1.05/1.1.00/02.0068).
Patient Care: May improve the efficacy of GBM treatment
Learning Objectives: By the conclusion of this session, participants should be able to understand a new possibility of targeting glioblastoma stem cells.
References: This work was supported by grants of Internal Grant Agency of the Czech Ministry of Health no. NT13514-4/2012, 15-33158A; and project "CEITEC - Central European Institute of Technology" (CZ.1.05/1.1.00/02.0068).