Fig. 4.

Role of estrogen receptor (ER) and STAT3 in CYP2E1 induction by PhIP in MCF-7 cells: CYP2E1 mRNA expression in the presence of STAT3 inhibitor 25 µM (a), STAT3 mRNA expression in the presence of PhIP and ICI 182,780 in MCF7 cells (b), CYP2E1 expression in the presence of ER inhibitor ICI 182,780 (1 µM) (c). DMSO (0.2%) was used as vehicle control. Statistically significant differences between PhIP vs. PhIP & ICI 182, 780/STAT-3 inhibitor co-treated samples were assessed by Student’s t test in GraphPad Prism 6. ***p < 0.001, **p < 0.01, *p < 0.05. Error bars represent the standard error of the mean (SEM) for independent cultures (n = 3). Proposed mechanism of PhIP-mediated CYP2E1 induction (d)