Fig. 3

PDEF promotes the proliferation of ER-negative BC cell lines. a AR and PDEF protein levels in the two ER-negative BC cell lines MDA-MB-453 and SKBR-3 were determined by performing western blotting. b RT-qPCR and western blotting were performed to detect PDEF expression in PDEF-overexpressing SKBR-3 cells. Data are presented as mean with SD. c RT-qPCR and western blotting were performed to detect PDEF expression in MDA-MB-453 cells infected with the four independent PDEF-targeting shRNAs. Subsequent experiments were performed using shRNA no. #2 (WT: wild type; NS: non-specific). Data are presented as mean with SD. d Results of the CCK-8 assay showed that PDEF overexpression promoted SKBR-3 cell proliferation (left) and that PDEF downregulation inhibited MDA-MB-453 cell proliferation (right); **P < 0.05. e Results of the flow cytometry analysis showing a significant increase in the number of S-phase cells among PDEF-overexpressing SKBR-3 cells and a significant decrease in the number of S-phase cells among PDEF-downregulated MDA-MB-453 cells; **P < 0.05. f and g Wound-healing (above) and Transwell (under) assays were performed to detect the invasion and migration potential of PDEF-overexpressing SKBR-3 cells or PDEF-downregulated MDA-MB-453 cells (wound-healing assay: original magnification, × 100; Transwell assay: original magnification, × 200); **P < 0.05. h Colony-forming assay was conducted to determine the clone-initiating ability of PDEF-overexpressing SKBR-3 cells or PDEF-downregulated MDA-MB-453 cells; **P < 0.05