(A) Representative photographs of the colony formation assay demonstrated that the smallest number of colonies was observed in the CD133knockout group compared with mock and GFP groups (mock vs. CD133 KO, P = 0.017; GFP vs. CD133 KO, P = 0.0172; *P<0.05). (B) WST-1 assay also showed a significant reduction in cell proliferation of CD133knockout cells compared with mock and GFP groups (***P<0.001). (C) In western blot, we confirmed that the CRISPR-Cas9 mediated CD133knockout cells in colony #1 and #2 showed decreased survivin expression, compared to the mock, GFP and CD133+ cells in colony #3. (GFP, CRISPR-Cas9 mediated control group; CD133 KO, CRISPR-Cas9 mediated CD133knockout group).