Characterization of stable CD44 knockdown cell lines. A. Western blot analysis: Equal amount of protein lysates (50 μg) made from indicated cell lines were immunoblotted with a CD44 antibody to detect total cellular levels of CD44 protein. C. Immunoblotting analysis of the total cellular levels of CD44 in the stable clonal isolates derived from PC3 cells transfected with CD44 ShRNA constructs (801 and 492; lanes 1–5) is shown. PC3 cells transfected with vector DNA (V) and scrambled ShRNA construct (Sc) were used as controls. B and D: Equal loading of protein was verified with the GAPDH level in each lane. The experiment was carried out three times with similar results.