Fig. 6

ERK activation is required for apoptosis induction by MTE treatment. a, b Apoptotic cells with indicated treatment were counted by Annexin V/PI assay. c, d The percentage of apoptotic cells with treatment was quantified. Early-stage apoptotic cells were shown in red, and late-stage apoptotic cells were shown in blue (M: MTE; U: U0126). e, f The protein level of Caspase 3 in treated cells was detected by Western blot, and the expression ratio was counted. Cells were treated with 20, 40, 80 mg/ml MTE for 24 h. g, h The caspase 3 activities in treated cells were detected. *P < 0.05, **P < 0.01, ***P < 0.005; Groups with U0126 vs groups without U0126