Exosomes derived from bone marrow mesenchymal stem cells promote proliferation and migration via upregulation yes-associated protein/transcriptional coactivator with PDZ binding motif expression in breast cancer cells.

Bone marrow mesenchymal stem cells (BM-MSCs), with the properties of self-renewal and pluripotency, can migrate to the tumor sites and exert complex effects on tumor progression and communications by releasing exosomes. However, to our knowledge, only a few studies have reported the effects of BM-MSCs exosomes on breast cancer cells development. Here, utilizing exosomes isolated from in vitro BM-MSCs, we systematically investigated this issue in a breast cancer cell line. In this study, we found that BM-MSCs exosomes are actively incorporated by breast cancer cell MDA-MB-231 cells and subsequently promote MDA-MB-231 cells proliferation and migration. Mechanistically, we further found Yes-associated protein (YAP) and transcriptional coactivator with PDZ binding motif (TAZ) which are Hippo signaling components were involved in this promoting progress. Consistently, YAP and TAZ knockdown could significantly reverse breast cancer cells proliferation and migration improved by BM-MSCs exosomes. Taken together, our findings demonstrated a new mechanism through which BM-MSCs-derived exosomes may contribute to breast cancer cells proliferation and migration, which might provide an evidence for novel drug discovery based on exosomes and Hippo signaling.