Consistent with the observed reduction in the expression of β-catenin and cyclin-D1 detected by western blotting, the results of immunohistochemistry indicated the expression of β-catenin and cyclin-D1 in tumor tissues of mice treated with hUCMSCs-LV-IL-21 was also significantly decreased compared with the control group, hUCMSCs group and hUCMSCs-LV-Vec group, respectively (Figure 4B). Here, CCND1 is linked to neoplasm.