Figure 1.

Selective inhibition of survivin promoter activity by YM155: A. Chemical structure of YM155. The two structural formats for YM155 have the same molecular weight (443.3). B. Subconfluent EKVX lung cancer cells were transfected with survivin promoter-luciferase constructs and treated with and without YM155 for 24 hours as shown, followed by a luciferase activity assay. C. Subconfluent EKVX cells were transfected with luciferase reporter constructs driven by promoters from the genes for DHFR, p21, HTR, and TK, followed by either no or YM155 treatment and luciferase activity assays as in B. Data are shown in histograms and each bar is the mean ± SD derived from three independent assays in panels B and C. D. YM155 inhibits endogenous survivin expression, but shows no inhibitory effects on the endogenous expression of p21 and DHFR. Subconfluent EKVX cells were treated with and without YM155 as shown for 24 hours. Cells were then lysed and analyzed by western blots using the corresponding antibodies. Actin was used as an internal control.