PCNA and adenomatous colon polyp: We observed the increase in infiltration of inflammatory cells, a key feature of sporadic adenomatous colonic polyps with an increased number of Ki67-, CD45-, β-catenin-, proliferating cell nuclear antigen (PCNA)-, and F4/80-positive cells (Figure 6E) in the Chi/PA-attached Nudt7+/+ colon polyp.