Anti-proliferative effects of APRE in different cell lines. (A) SH-SY5Y, B103, Rat-2 and NIH 3T3 cells were cultured in 96-well culture dishes to 50–60% confluence in DMEM containing 10% FBS. The cells were treated with various concentrations of APRE. Cell death was determined by using the cytotoxicity assay kit (CCK-8, Dojindo Lab). Each point is mean ± SE of quintuple of samples. Data is composed of the mean of three independent experiments in which the activity in absence of APRE compared to presence of APRE was significantly different (n = 5, *P < 0.05, **P < 0.01). (B) APRE dose of 6 μg/ml was added in a time course experiment. Results are mean ± SEM and representatives of three independent experiments are shown. Significant differences compared with untreated and APRE added for different times are indicated (n = 5, *P < 0.05).