Mesenchymal stem cells in the tumor microenvironment.

Mesenchymal stem cells (MSCs) are non-hematopoietic, multipotent cells, which are able to differentiate to bone, adipose and cartilage tissue. MSCs have the characteristic of migration to injured areas or tumor microenvironment following induction by chemokines or inflammatory factors. An increasing number of studies have reported that MSCs recruited to the tumor microenvironment play various roles in tumor cell development and tumor progression. In this study, we reviewed the studies related to the tumor-promoting roles of MSCs from several aspects, such as increasing stemness of tumor cells, mediating migration, promoting angiogenesis, suppressing immune response and inducing drug resistance.