(a-b) qRT-PCR in 42DENZR (a) and 42FENZR (b) cells following siRNA-mediated EZH2 silencing (siEZH2) for the indicated time, reported relative to non-transfected control cells at day 0 (mean ± SD; two-tailed unpaired t-test, n = 3). NTC, non-targeting control. (c-d) Spheroid formation and ALDH activity in 42DENZR (c) and 42FENZR (d) cells following siRNA-mediated EZH2 silencing (siEZH2; left) or treatment with increasing dose of EZH2 inhibitor (GSK126; right) for 8 days (mean ± SD; two-tailed unpaired t-test, n = 2). (e) qRT-PCR in 42DENZR cells treated with EZH2 inhibitor (10 μM GSK126) for 7 days, followed by removal (washout) for 14 days. Expression is reported relative to cells at day 0 (mean ± SD; two-tailed unpaired t-test, n = 3). Immunoblotting confirmed on-target effect.