Fig. 5

GRK6 and β-Arrestin activation promote the EMT progression and cellular migration activity by activating MAPKs in TNBC cells. A Volcano plot for log₂ fold change and –log₁₀ [adjusted p value (padj)] derived from the upregulated (red) and downregulated (blue) genes in the GRK6-silenced cells as compared to the non-silencing control cells in GSE164921 dataset. B The plot of enrichment score (ES) for the correlation between P38MAPK_PATHWAY gene set and the ranked somatic genes by log₂ fold change shown in A. C–E. Western blot analyses for the phosphorylated p38 (p-p38), total p38, p-Erk1/2, total Erk1/2 and GAPDH in whole cell lysates from the indicated HCC1937 cell variants (C), MDA-MB231 cells treated without or with GRK6 inhibitor at the indicated concentrations (D), and the VC/GRK6A-OE HCC1937 cells treated without or with β-Arrestin inhibitor at the indicated concentrations (E). F–G. Western blot analyses for the EMT markers in the whole cell lysates (F), and Giemsa stain for the migrated cells in the trans-well cultivation (G, upper) of VC and GRK6A-OE HCC1937 cells treated without or with p38 inhibitor SB203580 and Erk1/2 inhibitor U0126 at the indicated concentrations for 24 h. The migration cell number from three independent experiments were presented as mean ± SEM in the histogram (G, lower). The different alphabets indicate the statistical significance at p < 0.05. In C, D, E and F, GAPDH was used as an internal control of protein loading