Fig. 5
Endothelin A2 (Endo II) promotes human epidermal growth factor receptor 2 (HER2)-positive cancer cell motility and tumor metastasis. a HCC1954 pGIPZ non-targeted (NT) and Endo II knock-down (KD)1 cells were seeded in Transwell inserts (8 μm pores) and allowed to migrate towards the lower chamber containing serum-free medium supplemented with or without epidermal growth factor (EGF) (50 ng/ml) for 24 hours. Graph depicts the average cells per filter from assay triplicates and from three independent experiments (mean ± SEM; **P < 0.01, ***P < 0.001). b HCC1954 pGIPZ NT and Endo II KD1 cells were seeded in Transwell inserts coated with Matrigel and allowed to invade through the matrix and filter towards medium supplemented with 10% serum. Graph depicts the average cells per filter from assay triplicates and from three independent experiments (mean ± SEM; ***P < 0.001). c, d Experimental metastasis assays were conducted by tail vein injection of HCC1954 pGIPZ NT or Endo II KD1 cells (8.0 × 105) and after 2 weeks, GFP+ lung metastases were visualized and scored in mouse lung tissue (c) and from H&E-stained lung tissue sections (d) (n = 8/group, from two separate experiments; **P < 0.01, ***P < 0.001)