Figure 5F shows the process of animal experiments. And the Figures 5G–J show that the “Exo_siMTA1 + GEM” group significantly restricts the tumor growth, when compared with “Exo +GEM” group, which implies enhanced the chemotherapy sensitivity of MCF-7 to GEM by Exo_siMTA1 (p<0.001). In the H&E staining and ki-67 staining, we got the same results when compared with Figures 4H, I, all of which implies Exo_siMTA1 can enhance the tumor growth inhibition effect of GEM. This evidence concerns the gene MKI67 and neoplasm.