Integrins, IL-1RI, and uPAR expression in pancreatic cancer cell lines. Integrin subunits, IL-1RI, and uPAR 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 α6 integrin, αv integrin, β1 integrin, IL-1RI, and uPAR. β-actin Western blot served as a loading control.