Figure 5.

Maritoclax-induced cFLIP downregulation is not associated with proteasomal pathway. (A,B) Caki cells were treated with indicated concentrations of maritoclax for 24 h. The mRNA level was determined by RT-PCR (A). The protein expression levels were determined by Western blotting (B). (C) Caki cells were pretreated with proteasome inhibitors (1 μM MG132 and 2.5 μM lactacystin) and lysosomal inhibitors (10 μM chloroquine (CQ) and 10 nM bafilomycin A1) for 30 min, and then treated with 2 μM maritoclax for 24 h. The protein expression levels were determined by Western blotting. (D) Caki cells were treated with or without 2 μM maritoclax in the presence of 20 μg/mL cycloheximide (CHX) for the indicated time periods. The protein levels were determined by Western blotting (left panel). The band intensity of the cFLIP protein was measured using ImageJ (public domain JAVA image-processing program; http://rsb.info.nih.gov/ij, right panel). −, no treatment; +, treatment.