MKI67 and neoplasm: Ki67 immunohistochemistry staining showed that compared with the control group, the number of Ki67-positive cells decreased significantly in the DOX group and the DOX ultrasound group (p < .05), while the number of Ki67-positive cells decreased more significantly in the DOX-BCND ultrasound group (p < .05) (Figure 9), indicating that the application of DOX-BCNDs could significantly inhibit the proliferation of tumor cells.