Figure 5
Blockade of the TNFα-mediated TNF-R1 extrinsic death pathway confers resistance to PRL-3 knockdown-mediated cell death, while inhibition of NF-ĸB following PRL-3 knockdown sustains TNBC cell survival through c-Jun/AP-1. Real-time kinetic monitoring of BT-20 cell proliferation as determined by the IncuCyte Zoom Live Cell Imaging System. Control cells (green) and PRL-3 knockdown cells (red) were treated with vehicle (blue) or the following inhibitors (black): (a) TNF-R1 internalization inhibitor (monodansylcadaverine (MDC), 100 μM), (b) Caspase-8 inhibitor (Z-IETD-FMK, 20 μM) or (c) Caspase-9 inhibitor (Z-LEHD-FMK, 20 μM). (d) BT-20 cell proliferation as assessed in (a–c) with IKK inhibitor (PS-1145, 10 μM). (e) Immunoblot analysis examining changes in activation of c-Jun assessed by phosphorylation of serine 73 in control (pLKO) and BT-20 cells with PRL-3 knockdown (shPRL-3) treated with PS-1145 (10 μM). (f) Fold change of AP-1 activity in PRL-3 knockdown BT-20 cells transfected with an AP-1-luciferase reporter plasmid and treated with PS-1145 (10 μM). Data represented are the mean±s.d. of three independent experiments. *P<0.05 as determined by Student t-test on final data point.
