Fig. 5

Xanthohumol-decreased survivin Thr34 phosphorylation is required for survivin ubiquitination. a and b OSCC cells were treated with xanthohumol for 24 h, the whole-cell lysate was subjected to IB analysis. c SCC25 cells were transfected with siCtrl or siAkt and treated with xanthohumol for 24 h, and whole cell lysate was subjected to IB analysis. d SCC25 cells were transfected with Mry-Akt1 and treated with xanthohumol for 24 h, the whole-cell lysate was subjected to IB analysis. e-g SCC25 cells were treated as in “Figure 5d”, cells were subject to MTS assay (e), cleaved-caspase 3 activity analysis (f), and IB analysis (g). h SCC25 cells were transfected with Flag-Survivin-WT or T34A and treated with xanthohumol for 24 h, the whole-cell lysate was subjected to IB analysis. i SCC25 cells were transfected with Flag-Survivin-WT or T34A and treated with xanthohumol for 24 h. CHX was added into the cell culture medium for various time points. The whole-cell lysate was subjected to IB analysis. j SCC25 cells were transfected with various plasmids and treated with xanthohumol for 24 h. The whole-cell lysate was subjected to ubiquitination analysis. k and l Survivin WT or knockout SCC25 cells were transfected with survivin WT or T34A mutant and treated with xanthohumol as indicated. Cells were subjected to MTS assay (k) and cleaved-caspase 3 activity analysis (l). ***p < 0.001