Figure 6

Xenoestrogen- and tamoxifen-regulated miRNA (miR)-34b expression in breast cancer cells. (A) miR-34b expression in MCF-7 cells after 24-hour treatment with estradiol, xenoestrogens or tamoxifen (n = 3). The results are normalized to internal U6 snRNA expression. CTRL = control; E2 = 10 nM 17β-estradiol; DES = 100 nM diethylstilbestrol; ZEA = 100 nM zeranol; TAM = 100 nM tamoxifen. (B) Western blot of cyclin D1 after 24-hour treatment with E2, xenoestrogens or TAM in MCF-7 cells. β-actin was probed as an internal control. Graphs at bottom present the Western blot analysis quantitative data (n = 3). (C) Western blot of JAG1 in MCF-7 after 24-hour treatment with E2, xenoestrogens or tamoxifen (n = 3). E2 = 10 nM estradiol; DES = 100 nM diethylstilbestrol; ZEA = 100 nM zeranol; TAM = 100 nM tamoxifen. β-actin was probed as an internal control. (D) Quantitative PCR of miR-34b/c expression in MCF-7 cells following 10 nM E2, 100 nM TAM or combined treatment (n = 3). The results were normalized to internal U6 snRNA expression. (E) Western blot showing JAG1 in MCF-7 after 24-hour treatment with E2, tamoxifen or combined treatment (n = 3). E2 = 10 nM estradiol; TAM = 100 nM tamoxifen. β-actin was probed as an internal control. (F) Quantitative expression of miR-34b and miR-34c after E2 treatment in MCF-7 breast cancer cells, mouse primary endometrial cells and OVCAR4 ovarian cancer cells (n = 3). The results were normalized to internal U6 snRNA expression and are expressed as means ± SD. *P < 0.05.