Effect of inducible knockdown of G9a. (A-B) Validation of G9a knockdown. XG-7 cells were transduced with 3 shG9a constructs and cultured or not with doxycycline (Dox; 1 mg/mL) for 3 or 5 days, after which G9a RNA (A) and protein (B) levels were analyzed using qRT-PCR and western blot, respectively. For the qRT-PCR data, data represent the mean ± standard deviation (SD) of 3 independent experiments. For the western blot data, tubulin was used as loading control, and 1 experiment representative of 3 experiments is shown. (C) Effect of G9a knockdown on cumulative cell growth. XG-7 cells transduced with shG9a#1 were cultured or not with doxycycline (DOX; 1 mg/mL) for 14 days. Cumulative cell counts were measured using trypan blue staining at the indicated time points. Results are mean ± SD of 4 independent experiments. *P < .05 vs control (CTR).