Knockdown of YAP attenuated KLF5 protein, but not mRNA expression. (A) 5637 cells were transfected with siRNAs specifically targeting YAP (si YAP # 1,2) or non-specific control (si NC). Thirty six hours after transfection, total RNAs were isolated, and the expression of YAP, TAZ, KLF5 and cyclin D1 were analyzed by real-time qPCR; (B) Twelve hours after transfection, cells were trypsinized and seeded for an MTT assay; (C) After DMSO or MG132 (10 μM) treatment for 12 h, siRNA-transfected cells were lysed for western blot analysis by using antibodies specific to YAP, TAZ, KLF5 and cyclin D1. The data shown are representative of three independent experiments with similar results; bars, SDs. * p < 0.05.