PCNA and neoplasm: The number of cells positive for PCNA was significantly increased in the liver with the following features: (1) the control group had some scattered cells with weakly positive staining of the nucleus; (2) weak positive and scattered strong positive nuclear staining in the nontumor areas of the Con-Can and Cd-Can groups; and (3) strong positive nuclear staining localized in the tumor areas of the Con-Can and Cd-Can groups (Figure 5(c), Table 2).