PTK2 and non-small cell lung carcinoma: Given that the three EGFR TKI-resistant NSCLC cell lines had IC50 values for PF-228 ranging from 5 to 10 μM, and that our lab had previously observed inhibition of both autophosphorylation and kinase activity of FAK at 5 μM PF-228 [20], we confirmed the activity of this inhibitor in A549 cells following in vitro kinase assays for FAK autophosphorylation.