PKA antagonist treatment of ApcMin/+ mice decreased COX-2, β-catenin and c-Myc expression in small intestinal tumor tissue. A. The intensity of the β-catenin and COX-2 staining was calculated as the mean inverse grayscale intensity of tumor area (Image J 1.43u software package). Percent β-catenin and c-Myc positive nuclei were also assessed. Data are presented as Box plots with median (horizontal line); 25-75% (box) and 2.5-97.5% (bar) percentiles shown for each treatment group. Median values compared with Mann-Whitney Rank Sum test when Shapiro-Wilk Normality test failed; otherwise mean values compared by Student's t-test. N = no. of tumors examined (tumors from every animal in each treatment group were investigated). B. Micrographs of representative tumors from the PBS and Rp-8-Br-cAMPS (Rp-8-Br) treated groups stained with β-catenin, c-Myc and COX-2 antibodies.