Figure 1.

Individual Bcl-2 family protein expression levels did not predict the sensitivity to S1-induced apoptosis in leukaemic cell lines. (A) Leukaemic cell lines were cultured with increasing doses of S1 for 24 h, and then stained with Annexin V for flow cytometry analysis. The means of three independent experiments are shown. Data are the mean±s.e.m. (n=3). (B) S1 and ABT-737 induce apoptosis in WT but not Bax^–/–Bak^–/– (DKO) MEFs. Wild-type or Bax^–/–Bak^–/– MEFs were incubated for 48 h with S1 or ABT-737, and cell viability assessed by the 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Data are the mean±s.e.m. (n=3). (C) Immunoblot analysis of five leukaemia cell line lysates (100 μg of protein) with the indicated antibodies. Actin was used as a loading control. (D) pBcl-2 level did not predict LD₅₀ of S1 well in leukaemia cell lines. Protein expression levels were defined by immunoblot analysis using the Kodak Carestream Molecular Imaging software and plotted against the LD₅₀. The Spearman's rank correlation coefficient is indicated. Spearman's correlation (r) and P-values are also shown.