Knockdown of β-C reduces the proliferation and survival response of hPAECs to BMP-2 and Wnt3a but enhances their migratory response. (A) Western immunoblots for β-C and α-tubulin of hPAECs nucleofected with nontargeting control (CON RNAi) and β-C–specific siRNA (βC RNAi). ***, P < 0.0001 (compared with nontargeting control). (B–D) Cell proliferation (B), caspase 3/7 activity (C), and cell migration (D) assays using cells nucleofected with nontargeting or β-C–specific siRNA were performed as in Fig. 1. Error bars represent mean ± SEM from three different experiments performed in triplicate. **, P < 0.001 (BMP-2 or Wnt3a vs. unstimulated nontargeting control); #, P < 0.01 and ##, P < 0.001 (β-C–specific siRNA vs. corresponding nontargeting control).