Fig. 2

ADAMTS18 deficiency increases the risk of HER2-positive mammary tumorigenesis and metastasis. (A) Representative images of spontaneous mammary tumors and the incidence of macroscopic mammary tumor cases in Her2^t/t mice with FVB background (12 of 12, 100%), and Her2^t/w/Adamts18^+/+ mice (2 of 36, ~ 5.6%) and Her2^t/w/Adamts18^−/− mice (10 of 32, ~ 31%) with FVB-C57BL/6 mixed background. (B) The mean latency of spontaneous mammary tumors in tumor-bearing mice. Red represents the formation of multiple tumors in an individual mouse. Each dot, square, or triangle represents an individual. (C) Representative images and HE staining of mammary tumors and lung metastasis from the indicated genotypes. Brown arrow, lung tumor. Scale bars, 20 and 100 μm, respectively. In Her2^t/w/Adamts18^-/- mice (middle and lower panels), tumor type in the lungs was consistent with the primary site of the mammary tumors. (D) The incidence of tumors in distant organs of Her2^t/w/Adamts18^+/+ mice (n = 36) and Her2^t/w/Adamts18^−/− mice (n = 32). *p < 0.05; **p < 0.01; ***p < 0.001; p values of tumor incidence between two groups were determined through chi-squared analysis