Figure 4.
Effects on protein expression. (a) Effects of PEP005 (50 nM) on caspases and other apoptosis-related proteins were determined by Western blotting in four CTCL cell lines at 24 h of treatment. (b) For caspase-3, 48 h treatment was also investigated. (a,b) An amount of 30 µg of each protein extract was loaded per lane. Blots were probed with antibodies for caspase-8 (proform, 57 kDa; cleavage products, 43, 41 kDa), caspase-9 (cleavage product, 35 kDa), caspase-3 (proform, 35 kDa; cleavage products, 21, 19, 17 kDa), c-FLIP long/short isoforms (c-FLIPL/S, 50/25 kDa), XIAP (53 kDa), p53 and p21 (53 and 21 kDa, respectively). The housekeeping protein GAPDH (37 kDa) was used as the loading control. Two independent series of protein extracts and Western blotting experiments revealed highly comparable results.