Fig. 2: RANK promoted the metastasis of CRC cells in vitro and in vivo.

a Protein expressions of RANK were detected by western blot analysis in seven CRC cell lines. b, c RANK stable overexpression or knockdown efficiency was confirmed by western blotting in CRC cells. d, e RANK overexpression promoted the migration and invasion of SW480 and Caco2 cells. And the addition of 100 ng/ml RANKL moderately increased the migration and invasion of RANK-overexpressing SW480 and Caco2 cells. Scales bars = 100 μm. f Knockdown of RANK inhibited the migration and invasion of HT29 cells. Scales bars = 100 μm. g Bioluminescent images of representative mice at week 15 after implantation. h The total tumor burden is quantified as total photons measured by bioluminescent technology. i Livers were excised for ex vivo bioluminescent imaging. j Representative results for staining of metastatic nodules (black arrows) in the livers. Scales bars = 500 μm (40×), 200 μm (100×). k The statistical analyses of metastatic nodules. Data are mean ± SD (n = 3; n = 6 mice/group for in vivo experiments). *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.