Fig. 5. Activation of caspase-8 and cleavage of Bid in response to CDDO.
A, U-937, HL-60, and U-937/Bcl-xL cells were
treated with 5 µM CDDO and harvested at the indicated
times. U-937 cells were also treated with 10 µM ara-C and
harvested at 2 h. Total cell lysates were assayed for caspase-8
activity. The results are expressed as fold-increase in caspase-8
activity compared with control (means of two independent experiments,
each performed in duplicate; bars, SD).
B, U-937 or HL-60 cells were treated with 5
µM CDDO and harvested at the indicated times. Total cell
lysates were analyzed by immunoblotting with anti-Bid antibody.
IB, immunoblot; FL, full length;
CF, cleaved fragment.