Figure 6

Effect of overexpression of dn-STAT3 protein on induction of survivin by IL-11. HUVEC were transduced by retroviruses encoding either EGFP or dn-STAT3 (STAT3[Y705F]-FLAG). A, Transduced cells were made quiescent as described in Figure 2 and stimulated with IL-11 (5 ng/ml) for 12 hours and analyzed for either survivin (upper panel) or β-actin (lower panel) protein by immunoblotting as described in “Materials and Methods.” B, Transduced HUVEC were stimulated with IL-11 (5 ng/ml) for 10 minutes and analyzed for either STAT3 phosphorylation (P-STAT3, Tyr705, upper panel) or β-actin (lower panel) by immunoblotting as described in “Materials and Methods.” Data are from one of three experiments involving two independent sets of transductants with similar outcome.