Fig. 1

DT2216 selectively kills Bcl-xL-dependent TCL cell lines by degrading Bcl-xL in a VHL-dependent manner. a A represent immunoblot analysis of expression of various Bcl-2 family proteins and VHL in selective TCL cell lines. b Effects of DT2216 and ABT263 on MyLa cell and platelet (PLT) viability after 72 h treatment. The data are mean ± SEM (n = 3 independent assays). c DT2216 induced Bcl-xL degradation in a dose-dependent manner. MyLa cells were pretreated with or without QVD for 4 h, and then treated with DT2216 for 16 h. d DT2216 induced Bcl-xL degradation in a time-dependent manner. e ABT263 and/or the VHL ligand (VHL-L) could not induce Bcl-xL degradation. f ABT263 pretreatment blocked the degradation of Bcl-xL by DT2216. g VHL-L pretreatment blocked the degradation of Bcl-xL by DT2216. h MG132 blocked the degradation of Bcl-xL by DT2216. i DT2216 could not induce Bcl-xL degradation in VHL-null 786-O cells. j DT2216, but not its negative control compound (DT2216 NC), induced Bcl-xL degradation and cleavage of caspase-3 and PARP. For Fig. 1e–h, MyLa cells were pretreated with indicated compounds for 2 h, and proteins were measured 16 h after treatment with DT2216. k Pretreatment with VHL-L blocked the effect of DT2216 on cell viability. MyLa cells were pretreated with VHL-L for 2 h, and then treated with DT2216 for 72 h. The data are mean ± SD (n = 6 replicates). a p < 0.05 vs. DT2216. l DT2216, but not DT2216 NC, reduced the cell viability that was assayed after treatment with DT2216 or DT2216 NC for 72 h. The data are mean ± SD (n = 6 replicates). m DT2216-induced Bcl-xL degradation persisted up to 48 h upon the removal of DT2216 after 24 h DT2216 treatment. n The effect of DT2216, but not ABT263, on reducing MyLa cell viability, persisted up to 48 h upon the removal of ABT263 or DT2216 after 24 h treatment. The data presented are mean ± SD (n = 3 replicates)