Figure 4.

Blocking early steps of nongenomic pathway affecting the action of TCDD. MCF10A cells were preincubated with 10 μm MNF, 10 μm EGTA/AM, or 20 μm MAFP, respectively, for 30 min. A, Cells were then treated with 10 nm TCDD for 24 h. The mRNA induction levels of selected genes were measured. The results are expressed as fold of induction after TCDD treatment, and the statistically significant differences between the TCDD-only group and other groups are indicated by * (P < 0.05) or ** (P < 0.01). B and C, Cells were then treated 10 nm TCDD for 6 h (for AP-1 probe) or 24 h (for C/EBP probe), and the binding activities to those probes were shown.