PI3K inhibition blocks TNF-α-induced apoptosis in EMT/pU6m3, EMT/siTR1, and EMT/siTrx1 cells.

<p>(A) Cells were untreated or treated with TNF-α (10 ng/ml) for the indicated time intervals. Phosphorylated (upper panels) and total ERK 1/2, p38, and JNK 1/2 (lower panels) were measured by western blotting. (B) Cells were pre-treated with PI3K inhibitor, LY294002 (5 µM, designated LY), JNK inhibitor II (10 μM, designated JI), NAC (0.5 mM), or buffer and treated with TNF-α. Cleaved caspase-3 was measured by western blotting. (C) Cells were pre-treated with buffer, JNK inhibitor II (JI) or LY294002 (LY) and then treated with TNF-α. The percentages of apoptotic cells were measured by flow cytometry and are shown in the graphs. Experimental details for each study are given in the Materials and Methods. Experiments were carried out in duplicate and representative data are shown.