Mesenchymal stem cells (MSCs) have affinity to
tumor sites where they home, affecting their biology and growth. Previously, we have isolated mesenchymal cells from the decidua of the human placenta named as decidua-derived MSCs (DMSCs). The aims of the present study were to investigate the migration capacity of DMSCs in vitro, and in vivo in a preclinical model of mammary
tumors induced by N-nitroso-N-
methylurea (NMU). Additionally, we assessed the safety of
DMSC administration in vivo and their effect on
tumor growth. In vitro studies showed that DMSCs significantly migrate toward both, healthy human breast tissue and breast
adenocarcinoma. Nevertheless, the effect on
DMSC migration was significantly higher in the presence of
tumor tissue. DMSCs also significantly migrated in vitro in the presence of NMU-mammary
tumor homogenate when compared with control media alone. In vivo studies showed both migration and engraftment of DMSCs into NMU-induced
tumors. Interestingly, DMSCs showed an inhibitory effect on the growth of primary
tumors and in the development of new
tumors. DMSCs did not affect the growth of secondary
tumors, although secondary
tumors appeared 2 weeks later, and the number of secondary
tumors was lower in the
DMSC-treated rats as compared with vehicle-treated rats. To our knowledge, this is the first report showing placental MSCs effect on
tumor growth. In conclusion, DMSCs could serve as a therapeutic agent themselves and as a cellular vehicle of anticancer drugs.