KU inhibits liver metastasis in an orthotopic murine colorectal cancer model. (A) Representative images of liver tissues isolated from four mice treated with DW or KU. (B) Quantitative analysis of metastasis score in isolated mouse liver tissues from the orthotopic liver metastasis model (n = 4 each group). (C) Hematoxylin and eosin staining and immunohistochemical analysis of phosphor-Histone H3 (pHH3) of isolated liver tissues from the mouse liver metastasis model. Scale bars, 500 μm. (D) Representative images of IVIS luciferase results in mice inoculated with colorectal cancer cells. (E) Quantitative analysis of signals from the IVIS luciferase images. On day 3 after tumor establishment, mice were analyzed by optical bioluminescence imaging at 2, 9, and 16 days after intraperitoneal KU administration (5, 10, and 20 mg/kg/mouse, three times a week). Control groups received DW instead of treatment. The average signal intensity of 20 mg/kg KU-treated mice was weaker than that of control mice (P = 0.105) at 16 days after tumor cell inoculation. (F) Liver function test results of AST and ALT levels in tumor tissue. Results are reported as the mean ± standard error of the mean, n = 4, *P < 0.05, **P < 0.01, ***P < 0.001.