Skip to main content
Figure 6 | Breast Cancer Research

Figure 6

From: Downregulation of the tumor-suppressor miR-16 via progestin-mediated oncogenic signaling contributes to breast cancer development

Figure 6

miR-16 is a tumor suppressor in HRG-induced breast cancer growth. A, BT-474 cells were treated with 10 nM MPA for 24 hours and proliferation was measured by [3H]-thymidine incorporation as described in Figure 2D. B, BT-474 cells were treated with 10 nM MPA for the times shown. miR-16 expression levels were determined by RT-qPCR, and data analysis was performed as described in Figure 2A. C, BT-474 cells were treated with MPA for the times shown and WB was performed with an anti-c-Myc antibody (left panel) or with an anti-cyclin E antibody (right panel) and filters were reprobed with an anti-β-tubulin antibody. In the WB, cyclin E LMW isoforms are shown. D, BT-474 cells were treated with 40 ng/ml HRG for the times shown and miR-16 levels were measured as described in Figure 2A. E, BT-474 cells were transfected with pre-miR-16 or pre-miR-CTRL, and proliferation was evaluated by [3H]-thymidine uptake as described in Figure 2D after 24 hours of HRG treatment. In the right panel, as a control for transfection efficiency, miR-16 levels are shown in pre-miR-16- and pre-miR-CTRL-transfected BT-474 cells. F, BT-474 cells were treated with 40 ng/ml HRG for the times shown, and WB was performed with anti-c-Myc antibody and filters were reprobed with an anti-β-tubulin antibody. G, BT-474 cells were transfected with Stat3, c-Myc and CTRL siRNAs and then treated with HRG for 24 hours. miR-16 levels were studied by RT-qPCR, and data analysis was performed as described in Figure 2. The experiment shown was performed with Stat3 siRNA #3 and c-Myc siRNA #5, but the same results were obtained with Stat3 siRNA #1 and c-Myc siRNA #6. Experiments shown in A to G were repeated in triplicate with similar results. The data shown represent the means of three independent experiments ± SEM (P < 0.001 for b versus a and c versus b). HRG, heregulin; LMW, low molecular weight; MPA, medroxyprogesterone acetate; SEM, standard error of the mean; WB, western blot.

Back to article page
\