Description
To provide further insight about the effects of prolonged Ezh2 inhibition in glioblastoma using preclinical mouse models and doxycycline-inducible shRNAs that mimic the effects of a selective EZH2 inhibitor. We demonstrate that prolonged Ezh2-depletion causes a robust switch in cell fate, including significantly enhanced proliferation and DNA damage repair and activation of part of the pluripotency network, resulting in altered tumor cell identity and tumor progression. Overall design: SVZ derived neural stem cells (NSCs) were isolated from 7 days old p53;Ink4a/Arf;Krasv12;LucR compound conditional mice and cultured in NSC specific serum-free medium supplemented with 20ng/ml of both EGF and bFGF (R&D systems). NSCs were grown adhesion-free for the first passages to eliminate non-sphere-forming cells. Next, cells were grown adherent on poly-L-Ornithine and Laminin plates and three times infected with lentiviral CMV-Cre. These floxed, tumorigenic cells are further referred as glioma initiating cells (GICs). Next, GICs were infected with a tet-inducible, doxycycline-responsive short hairpin construct (FH1-tUTG-shEzh2). After FACS sorting for GFP, GICs were injected intracranial in NOD-SCID mice and treated with or without doxycycline in the drinking water