Fig. 7

Therapeutic effect of a miR-29a inhibitor in treatment of metastatic breast cancer. A Schematic representation of the procedure to treat the mammary tumor mice with anti-miR-29a, followed by analysis of metastasis in the lung. B Representative images of the metastatic breast tumor cells (RFP-labeled MDA-MB-231) in the lung after adhesion to culturing plate from lung single cell suspension. Application of anti-miR-29a inhibitor significantly decreased the tumor metastasis (n = 5 in each group). C FACS analysis indicated the percentage of the metastatic tumor cells in the lung of each mouse (n = 5 in each group). D Quantitative analysis of C. Data are presented as the mean ± SEM (n = 5). *p < 0.05. E Western blot demonstrated suppression of EMT markers vimentin, fibronectin and snail in expression in the mammary tumors after treatment with anti-miR-29a inhibitor. F Schematic representation of the procedure to treat the mammary tumor mice with anti-miR-29a, followed by analysis of CTCs in blood. G, H Real-time tracking of CTCs in the mammary tumor mice at day 25 after transplantation with MDA-MB-231 cells with or without treatment with anti-miR-29a inhibitor. In vivo flow cytometry (IVFC) assay was applied. n = 3 in each group. I Western blot demonstrated inactivation of PI3K-AKT signaling in the mammary tumors after treatment with anti-miR-29a inhibitor, in which p-AKT, p-p65 and β-catenin showed decrease while PTEN showed increase in expression. J Schematic representation of the mechanism through which ERα-miR-29a signaling controls metastasis in breast cancer