Fig. 6.

Regulation of ERK1/2 signal activation in cancer‐associated fibroblasts. (A) Sub‐confluent fibroblasts from 16 pairs of control fibroblasts and CAFs were cultured, and proteins were extracted and subjected to western blot analysis to detect (B) p‐ERK1/2 expression levels. Vertical axis: expression of protein normalized to t‐ERK1/2. (B; n = 16, Wilcoxon) (C) Effect of various concentrations of ERK inhibitor CAS 1049738‐54‐6, with or without TGF‐β1 (10 pm), on HFL‐1 cells was assessed with migration assay toward fibronectin (20 µg·mL⁻¹). (C; n = 3, one‐way ANOVA) Vertical axis: number of migrated cells per 5HPF. (D) Effect of various concentrations of CAS 1049738‐54‐6, with or without TGF‐β1 (10 pm), on HFL‐1 cells was assessed with migration assay toward collagen type I (1 µg·mL⁻¹). (D; n = 3, one‐way ANOVA) Vertical axis: number of migrated cells per 5HPF. Sub‐confluent HFL‐1 cells were cultured and treated with or without TGF‐β1 (10 pm), and CAS 1049738‐54‐6 (10 μm) for 24 h. Proteins were extracted and subjected to western blot analysis to detect the (E) ITGA11, (F) COL11A1, and (G) fibronectin expression levels. (E, F, G; n ≥ 3, unpaired Student's t‐test) Vertical axis: expression of protein normalized to β‐actin. Each symbol represents one patient. The values represent the mean ± SD. Pts: patients. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.