MKI67 and neoplasm: In addition, the SUNE1 and SUNE2 cells with differential vectors transfection were used to establish xenograft tumor-bearing mice models, and the results suggested that microRNA-338-5p overexpression slowed down tumor growth (P < 0.05, Figures 2E–G) and decreased the expression levels of Ki67 protein (Figure 2H) to inhibit tumorigenesis of NPC cells in vivo, while silencing of microRNA-338-5p had opposite effects (Figures 2E–H).