Figure 6

E2F4 is overexpressed, phosphorylated and nuclear localized in epithelial cells of human colorectal adenomas. A. E2F4 and β-actin protein levels were determined in six paired specimens of advanced adenomas by Western blot (resection margins (M) and primary tumors). B. E2F4 expression levels were normalized to β-actin levels. E2F4 expression levels were also normalized to a mean of E2F4 expression levels in every resection margins, resulting in a fold induction value. E2F4 protein contents in adenoma tissues relative to their corresponding normal samples were analyzed by paired t-test. **, Significant at p < 0.01. C. Representative immunohistochemistry of E2F4 from frozen tissue sections of resection margin and corresponding adenoma. Bars: 100 μm. Higher magnifications are shown on the left panels.