Figure 4.

(a) Representative survival curves of MDA-MB-231 cells in the presence of ERK1/2-inhibitor SCH772984 for 72 h revealed a higher sensitivity of the integrin β₁-knockdown (ITGB1-kd) cells towards ERK1/2-inhibition compared to scrambled (sc) cells and a higher resistance upon collagen type 1 (COL1) binding, indicated by the statistical analysis on these cytotoxicity data shown in (b) (n = at least 5 biological samples). (c) Western blot analysis of pERK/ERK and pHSP27/HSP27 with GAPDH as loading control after incubation with ERK1/2–inhibitor SCH772984 in MDA-MB-231 cells (n = at least 3 biological samples). (d,e) Combination effect of 7rh and SCH772984 cytotoxicity in MDA-MB-231 cells shows the pEC₅₀ values of Discoidin Domain Receptor 1 (DDR1) inhibitor 7rh cytotoxicity in the dependence of SCH772984 (n = at least 3 biological samples). MDA-MB-231 cells display a significant increase in pEC₅₀. Statistical analysis was performed via unpaired t-test (* p < 0.05; ** p < 0.01; *** p < 0.001).