NKD1 and Familial adenomatous polyposis: Pearson's correlation analysis of the FAP cohort shows a significant correlation coefficient of 0.78 between sFRP1 down-regulation and NKD1 up-regulation, but there is little correlation between sFRP1 and c-myc levels (r=0.098), indicating that c-myc does not have a major role in suppression of sFRP1 in these adenomas.