Figure 2.

Effects of AML1/ETO expression on hypoxia-induced apoptosis. U937 or U937-A/E cells were incubated for 2 days (from day −2 to time 0, t 0) in normoxia, in the absence (–) or the presence (+) of 5 μM ponasterone (PON) added daily (a–c), and then in normoxia or hypoxia (H, N) for 3 days (b) or in hypoxia for the indicated times (days; c). (a, c) Cell lysates were subjected to SDS-PAGE and immunoblotting with antibodies raised against ETO or the indicated proteins. Equalization of protein loading was verified on the same membrane. Representative results from one out of three independent experiments of each type are shown. (b) The percentages of apoptotic cells, as determined by Annexin V test and flow cytometry, are reported as average±S.E.M. of data from four independent experiments. Significance of differences was determined by the Student's t-test (*P<0.05)