Expression of FAK and β1 integrin in pancreatic cancer cells. (A) FAK and β1 integrin protein expression in pancreatic cancer cell lines was determined in whole cell lysates by Western blotting analysis. Fifty micrograms of total cell lysates was separated on 10 % SDS-PAGE and transferred to polyvinylidene difluoride membranes. Membranes were probed with antibodies against FAK and β1 integrin. The β-actin Western blot served as a loading control. (B) Knockdown of FAK expression by siRNA was confirmed by immunoblotting in all three pancreatic cancer cells. Re-probing with an anti-β-actin antibody served as a control.