Figure 5

Disruption of Ptk6 impairs mammary gland tumor metastasis to the lung. (a) Lung sections from six B2;Ptk6^+/+ and six B2;Ptk6^−/− animals with similar tumor burden and similar-sized primary tumors were stained with hematoxylin and eosin, and data from three different representative pairs are shown. Fewer intravascular (tumor emboli) and parenchymal masses (arrows) were detected in B2;Ptk6^−/− lungs. Representative sections are shown for each animal. The size bar represents 200 μm. (b) Contributions of metastases to total lung tissue were quantified. B2;Ptk6^+/+: n=9, B2;Ptk6^−/−: n=6. *P-value=0.013. (c) Activating phosphorylation of PTK6 is detected in the metastatic tumor nodules/emboli in the lungs, although proliferation as measured by Ki-67 staining was not statistically different between B2;Ptk6^+/+ and B2;Ptk6^−/− mice. Sections from two different animals from each group are shown. The size bar represents 50 μm