TI - Results Up-regulation of PYK2 expression , Tyr402 and ERK1/2 PHOSphorylations , as well as cell migration in A549 cells . AB - PYK2 expression and activation , as indicated by Tyr402 phosphorylaTION and ERK1/2 PHOSphorylation were evaluated in HBE and A549 cells respectively . As normal lung cells , HBE cells expressed a low level of PYK2 with an undetectable PHOSphorylated Tyr402 . A basal ERK1/2 PHOSphorylation was also observed in HBE cells . However , we found much higher expression of PYK2 as well as Tyr402 and ERK1/2 PHOSphorylations in A549 cells ( p lt 005 , Fig 2a ) . Additionally , more migrated A549 cells ( 169 + - 36 ) at 12 h were detected than HBE cells ( 79 + - 19 , p lt 005 , Fig 2b ) by Transwell assay .