Figure 6. E1:ER promotes EMT through SNAI2 induction, while E2:ER represses SNAI2.

(A) CDH2, SNAI2, and VIM expression by qPCR in MCF7 control and after addition of 10 or 100 nM E1 or E2 for 24 h (n = 3).

(B) SNAI2 expression assayed by qPCR in T74D control and after addition of 10 nM E1 or E2 for 24 h (n = 3).

(C) Western blot of indicated proteins in MFC7 (left) and T47D (right) control and after 10 nM E1 or E2 treatment for 45 min.

(D and E) qPCR analysis of CDH1, CDH2, and SNAI2 expression (D) and western blot of E-cadherin and Slug (E) in E1- or E2-stimulated orthotopic MCF7 tumors (n = 3).

(F–H) Quantitative chromatin immunoprecipitation (ChIP)-qPCR assays of ERα (F), CBP/p300 (G), and NCoR1 (H) at an ERE half-site −464 bp of the SNAI2 transcription start site in estrogen-starved MCF7 controls or after 10 nM E1 or E2 for 45 min (n = 3).

(A–H) All graphs show mean (±SEM) from at least 3 biological repeat and triplicate replicate assays and p from Student’s t test and ANOVA, *p < 0.05, **p < 0.001, and ***p < 0.0001.

(I and J) Kaplan Meier plots from METABRIC data of overall survival (OS) (I) and disease-free survival (DFS) (J) in patients whose ER+ breast cancers show SNAI2 expression above or below the median; log rank p and hazard ratio, HR, (± confidence interval [CI]) indicated.

(K) Model shows different E1- and E2-mediated ERs and co-regulator recruitment at pro-oncogenic target gene sites such as SNAI2.