Figure 6

DCA regulates SKGT4 cell survival through induction of COX-2 expression via Erk1/2 and p38-dependent pathways. SKGT4 cells were stimulated with 300 μM DCA for 1–6 hr and analyzed for COX-2 expression by Western blot analysis (A). SKGT4 cells were treated with 10 μM PD98059, 2 μM SB203580 or 1 μM GÖ6976 for 30 min prior to the addition of 300 μM DCA for 6 hr followed by analysis of COX-2 induction (B). SKGT4 cells were treated with 5 mM acetylsalicylic acid (ASA) for 30 min preceding stimulation with 300 μM (C) or 400 μM (D) DCA for 6 hr. In panels A-D, total cell lysates were assessed by Western blotting using either anti-COX-2 or anti-PARP antibodies. anti-actin or anti-α-tubulin antibody used as loading control. In panels C and D, COX-2 expression and PARP cleavage were assessed by densitometry and normalised against actin or α-tubulin, respectively. Fold increases in COX-2 expression and PARP cleavage are given relative to resting cells. ELISA was utilized to assess DNA fragmentation (E). Results are given as fold induction of DNA fragmentation relative to unstimulated cells. Results are representative of three independent experiments.