Blocking Androgen Receptor/Androgen Receptor Variant7 Decreases Metastasis of Estrogen Receptor Positive Breast Cancer Cells Through Modulating Epithelial to Mesenchymal Transition

Abstract

Purpose: Androgen receptor (AR) is often expressed in breast cancer, but its role in estrogen receptor positive (ER+) type is controversial. Although AR and its splicing variant 7 (ARV7) play a role in the pathobiology of breast cancer, the precise mechanisms are not fully understood. Therefore, the aim of the current study is to determine the influence of the blockers of AR (Enzalutamide) and ARV7 (EPI-001) on metastasis and epithelial to mesenchymal transition (EMT) in T47D, an ER+ breast cancer cell line. Methods: T47D cells were cultured/treated with Enzalutamide or EPI-001; cytotoxicity and cell cycle analysis were determined using Sulphorhodamine-B (SRB) assay and Flowcytometry analysis, respectively, whereas metastasis was assessed by the Scratch wound healing assay. Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of AR, ARV7, C-myc, N-Cadherin, E-Cadherin, NF-κB, ROCK1 and 2 and Western blot was used for evaluating the protein expression of cyclin dependent kinases (CDK4, CDK6, Cyclin E), Fibronectin, vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP2 and MMP9). Results: Our results indicated that treatment with Enzalutamide or EPI-001 didn't significantly affect cell proliferation of T47D. However, cells were arrested at S-phase accompanied by a decline in CDK4, CDK6, Cyclin E and metastasis. Fibronectin, VEGF, MMP2, MMP9, ROCK1 and ROCK2 proteins were downregulated. C-myc and NF-κB levels were declined by EPI-001, but not Enzalutamide.Conclusion: Blocking AR/ARV7 has no effect on cell proliferation, but decreases metastasis by regulating key markers and processes involved in EMT in ER+ breast cancer cells.