Fig. 4

SKLB-D18 inhibited TNBC cell proliferation and metastasis in vitro. a Immunoblotting analysis of protein levels of ERK5, p-ERK5, ERK1/2, p-ERK1/2, p-RSKp90, RSKp90, p-c-Myc, and c-Myc in MDA-MB-231 and MDA-MB-468 cells following 24 h incubation with SKLB-D18 (1, 2.5, 5 μM), and combination of BVD-523 (5 μM) and XMD8-92 (5 μM). b Immunoblotting analysis of p-ERK1/2 and p-ERK5 expression levels following 24 h incubation with SKLB-D18 (5 μM) in MDA-MB-231 and MDA-MB-468 cells with or without pretreatment of BVD-523 (5 μM). c The antiproliferative capacity of cells following incubation with SKLB-D18 (1, 2.5, 5 μM), and combination of BVD-523 (5 μM) and XMD8-92 (5 μM) by clonogenic assay. d Quantification of fluorescence intensity and cell number via EDU staining following 24 h incubation with SKLB-D18 (5 μM), and combination of BVD-523 (5 μM) and XMD8-92 (5 μM). e Flow cytometry analysis of cell cycle arrest following 24 h incubation with SKLB-D18 (1, 2.5, 5 μM), and combination of BVD-523 (5 μM) and XMD8-92 (5 μM). f Transwell assay to quantify the number of cells migrating to the lower chamber following 16 h incubation with SKLB-D18 (0.5, 1, 2 μM), and combination of BVD-523 (2 μM) and XMD8-92 (2 μM). g Immunoblottng analysis of E-cadherin and MMP2 levels following 24 h incubation with SKLB-D18 (0.5, 1, 2 μM), and combination of BVD-523 (2 μM) and XMD8-92 (2 μM). h Immunofluorescence analysis of E-cadherin and MMP2 levels in cells following 24 h incubation with SKLB-D18 (2 μM), and combination of BVD-523 (2 μM) and XMD8-92 (2 μM). Data are presented as Mean ± SD. Compared to the Control group: *p < 0.05, **p < 0.01, ***p < 0.001