The human colon cancer cell lines SW48 and SW480 were co-transfected by nucleofection in different combinations with the following plasmids: two reporter plasmids for a luciferase-based assay, expression plasmids for Wnt-5a, for dominant negative forms of Siah1 or Siah2 (homologs 1 and 2 of Drosophila seven in absentia), and for the tumor suppressor protein APC (Adenomatous Polyposis Coli).