title: BIX01294, an inhibitor of histone methyltransferase, induces autophagy-dependent differentiation of glioma stem-like cells.
abstract: Glioblastoma (GBM) contains rare glioma stem-like cells (GSCs) with capacities of self-renewal, multi-lineage differentiation, and resistance to conventional therapy. Drug-induced differentiation of GSCs is recognized as a promising approach of anti-glioma therapy. Accumulating evidence suggests that unique properties of stem cells depend on autophagy. Here we demonstrate that BIX01294, an inhibitor of a G9a histone methyltransferase (introducing H3K9me2 and H3K27me3 repressive marks) triggers autophagy in human glioma cells. Pharmacological or genetic inhibition of autophagy decreased LC3-II accumulation and GFP-LC3 punctation in BIX01294-treated cells. GSCs-enriched spheres originating from glioma cells and GBM patient-derived cultures express lower levels of autophagy related (ATG) genes than the parental glioma cell cultures. Typical differentiation inducers that upregulate neuronal and astrocytic markers in sphere cultures, increase the level of ATG mRNAs. G9a binds to the promoters of autophagy (LC3B, WIPI1) and differentiation-related (GFAP, TUBB3) genes in GSCs. Higher H3K4me3 (an activation mark) and lower H3K9me2 (the repressive mark) levels at the promoters of studied genes were detected in serum-differentiated cells than in sphere cultures. BIX01294 treatment upregulates the expression of autophagy and differentiation-related genes in GSCs. Pharmacological inhibition of autophagy decreases GFAP and TUBB3 expression in BIX01294-treated GSCs suggesting that BIX01294-induced differentiation of GSCs is autophagy-dependent.
authors.affiliation: Laboratory of Molecular Neurobiology, Neurobiology Center, Nencki Institute of Experimental Biology of Polish Academy of Science, 3 Pasteur Str., 02-093 Warsaw, Poland.
authors.forename: Iwona Anna
authors.initials: IA
authors.lastname: Ciechomska
authors.affiliation: Laboratory of Molecular Neurobiology, Neurobiology Center, Nencki Institute of Experimental Biology of Polish Academy of Science, 3 Pasteur Str., 02-093 Warsaw, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Przanowski
authors.affiliation: Laboratory of Molecular Neurobiology, Neurobiology Center, Nencki Institute of Experimental Biology of Polish Academy of Science, 3 Pasteur Str., 02-093 Warsaw, Poland.
authors.forename: Judyta
authors.initials: J
authors.lastname: Jackl
authors.affiliation: Laboratory of Molecular Neurobiology, Neurobiology Center, Nencki Institute of Experimental Biology of Polish Academy of Science, 3 Pasteur Str., 02-093 Warsaw, Poland.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Wojtas
authors.affiliation: Laboratory of Molecular Neurobiology, Neurobiology Center, Nencki Institute of Experimental Biology of Polish Academy of Science, 3 Pasteur Str., 02-093 Warsaw, Poland.
authors.forename: Bozena
authors.initials: B
authors.lastname: Kaminska
mesh_terms: D001343:Autophagy / Q000187:drug effects*; D001381:Azepines / Q000494:pharmacology*; D001932:Brain Neoplasms / Q000473:pathology*; D002454:Cell Differentiation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005909:Glioblastoma / Q000473:pathology*; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase / Q000037:antagonists & inhibitors*; D006657:Histones / Q000037:antagonists & inhibitors*; D006801:Humans; D014411:Neoplastic Stem Cells / Q000473:pathology*; D011799:Quinazolines / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D001381:Azepines; C518299:BIX 01294; D004791:Enzyme Inhibitors; D006657:Histones; D011799:Quinazolines; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase