Figure 1

Effector caspase-3/7 activity and caspase-3 fragmentation in malignant pleural mesothelioma cells (P31) and a sub-line with in vitro acquired cisplatin-resistance (P31res1.2) determined in absence and presence of equitoxic and equiapoptotic concentrations of cisplatin, after exposure times as indicated. (a) Caspase-3/7 activity determined in a fluorometric assay using a fluorescent-tagged substrate, DEVD-AFC. ^**P<0.01, compared with control. Data presented as means±S.E.M. of three separate experiments. (b) Western blot of full-length and cleaved PARP as an endogenous indicator of caspase-3/7 activity. The membranes were stripped and reprobed for actin as a protein loading control. Image representative of at least three separate experiments. (c) Activation of caspase-3 determined by western blotting to detect full-length and cleaved versions of caspase-3. The membranes were stripped and reprobed for actin as a protein loading control. Image representative of at least three separate experiments. (d) P31 and P31res1.2 content of full-length caspase-3 and cleaved caspase-3 determined with a Proteome profiler array for human apoptosis-related proteins. Data presented as means±S.E.M. of duplicate analysis. (e) Detection of caspase-3 and caspase-7 by western blotting under control conditions in non-small cell lung cancer cells (H1299) and a sub-line with in vitro acquired cisplatin-resistance (H1299res)