PJ3-4 does not arrest either the TRAIL or STS-induced necroptosis in presence of caspase inhibitor.

<p>U937 cells were treated either with STS (1 µM) or with TRAIL (50 ng/mL) in the presence or absence of zVD (5 µM) for 20 hrs. PJ-34 (1 µM) was added 1 hr before cell death was induced. (A) Column diagram of percentage of cells with high DiOC₆(3) fluorescence intensity (n = 3). (B-C) PJ-34 (1 µM) considerably inhibited the (B) STS (n = 8) or (C) TRAIL-triggered (n = 8) secondary necrosis but not the necroptosis. Percentage of PI positive cells was determined. Values are mean±SD. *, P<0.05, **, P<0.01 and ***, P<0.001 calculated by Student’s t-probe. (D) Column diagram of percentage of cells with high AO fluorescence intensity (n = 2). (E) Dot plot distribution of cells stained with Annexin V-FITC and PI analyzed by flow cytometry. The values indicate the percentage of cells in the marked regions (representative of n = 2). (F) Representative histograms of distribution of PI stained, ethanol-fixed (sub-G1) cells were analyzed by flow cytometry (n = 8). The numbers indicate the percentage of cells in the marked regions. (G) PJ-34 concentration dependently reduced the proportion of PI positive cells for STS treatment for 20 hrs – representative experiment.