Figure 4. Loss of MYO1E expression delays tumor progression and reduces cell proliferation.

A. tumors from 16 week old MYO1E WT PyMT and KO PyMT mice stained with Cyclin D1 antibody and counterstained with hematoxylin at 10x (top) and 40x (bottom) magnification. Arrows indicate areas of peripheral Cyclin D1 enrichment in MYO1E KO tumors. Scale bar, 100 um. B. percentage of Cyclin-D1 positive cells in MYO1E WT and KO tumor acini that were localized to the periphery of the acini. This percentage is calculated relative to the total number of Cyclin D1-positive cells within the acini. For this analysis, three mice per genotype were examined, and 5 acini were analyzed per animal (p<0.05). Statistical analysis was performed on the percentage values from each mouse, rather than each individual acini. The error bar represents the standard deviation from three different mice. C. representative images of Ki-67 staining in tumors from 16 week old MYO1E WT and KO mice, with a hematoxylin counterstain. Scale bar, 100 um. D. percentage of Ki-67-positive cells in MYO1E WT and KO tumors at 16 weeks of age. For this analysis, three mice per genotype were examined, and 5 fields of view were analyzed per animal (p<0.05). The graph represents the average percent of Ki-67-positive cells in three mice, and statistical analysis was performed on the percentage values from each mouse, rather than each individual field of view. The error bar represents the standard deviation from three different mice. E. Western blot analysis of isolated tumor cells from MYO1E WT and KO PyMT mice indicates the presence of MYO1E in WT tumors cells and its absence in the KO tumor cells. F. representative images of Ki-67 staining in tumor cells isolated from MYO1E WT and KO PyMT mice. Ki-67 is shown in red, while DAPI is blue. G. graph showing percent of Ki-67 positive cells in MYO1E WT and KO tumor cells (p<0.001). Analysis was performed as detailed in D.