In a recent study, after overexpressing miR-940 in breast cancer cells, treatment of human mesenchymal stem cells (MSCs) with exosomes contained culture medium- was shown to promote osteogenesis in vitro by acting on Rho GTPase-activating protein 1 (ARHGAP1) and family with sequence similarity 134, member A (FAM134A) [75]. Here, ARHGAP1 is linked to breast cancer.