The results revealed that, compared with the leukemia cells in the control group and the EV group co-culturing with TGF-β conditioned MSCs, the migration and invasion of the leukemia cells in the co-culture system of Nalm-6/RS4;11-Si-ITGB1 and TGF-β conditioned MSCs group were significantly weakened (P < 0.05; Figures 7C,D). This evidence concerns the gene TGFB1 and leukemia.