Objectives: The primary objective of the study is to assess in patients with primary colon cancer whether short-course pre-operative treatment with decitabine can increase Wnt target gene expression as measured in resected tumors compared to pretreatment biopsies. The secondary objective of the study is to assess in patients with primary colon cancer whether short-course pre-operative treatment with decitabine can revert CpG methylation and induce more favorable tumor characteristics as measured in resected tumors compared to pretreatment biopsies. The tertiary objective is to compare changes in Wnt target gene expression, CpG methylation and tumor characteristics for Wnt methylated and nonmethylated tumors as measured in resected tumors compared to pretreatment biopsies and identify new stratification markers.