DCA induces PARP cleavage and DNA fragmentation with reduced cell proliferation in SKGT4 cells. SKGT4 cells were incubated with 300 μM DCA at the indicated time intervals (A) and at DCA concentrations ranging from 0 – 500 μM for 6 hours (B). In panels A and B, cellular proliferation was assessed using the MTT assay as described in experimental procedures. Results are expressed as percentage of proliferating cells relative to untreated controls. Mean ± SD. To investigate DCA induced PARP cleavage (C,), SKGT4 cells were stimulated with 300 μM DCA for the indicated times or with 0 – 500 μM DCA for 6 hr (D). 1 μM Staurosporine (ST) was used as positive control. In panels C and D, total cell lysates were standardized to 50 μg as described in experimental procedures and assessed by Western blotting using an antibody directed against cleaved PARP to detect apoptosis. Anti-actin antibody used as loading control. SKGT4 cell lysates were assessed for DNA fragmentation as described in Methods (E, F). Results are presented as fold induction of DNA fragmentation relative to unstimulated control. Mean ± SD.