MKI67 and neoplasm: Meanwhile, TUNEL staining and Ki-67 IHC staining indicated that the survival and proliferation status of tumor tissues in the Exo-Ts group were significantly better than those in the other two groups (Fig. 8C, D), suggesting that Exo-Ts can exert a tumor growth-promoting effect in vivo depending on the delivery of circTGFBR2.