Contribution of multipotent mesenchymal stromal cells in the tumor microenvironment and carcinogenesis

Abstract

Carcinogenesis is a complex and dynamic process, an important part of which is the formation of the tumor microenvironment, which is an integral part of malignant tumors and plays an important role in their progression. To maintain the growth and development of a tumor, constant contact and cross exchange of various trophic factors and cytokines with the cell of microenvironment, such as endothelial, immune, stromal cells, are essential. Multipotent mesenchymal stromal cells are an integral component of the tumor microenvironment, but their role in carcinogenesis is highly controversial. It has been described that multipotent mesenchymal stromal cells are able to stimulate tumor growth by differentiation into tumor-associated fibroblasts, immunosuppression, stimulation of angiogen-esis, participation in the epithelial-mesenchymal transition, inhibition of apoptosis, and maintenance of the metastatic potential of the tumor. However, other studies show that multipotent mesenchymal stromal cells suppress tumor growth by increasing inflammatory infiltration, inhibiting angiogenesis, suppressing WNT and AKT signals, and by directly inducing apoptosis of tumor cells. This review discusses the role of multipotent mesenchymal stromal cells in carcinogenesis, as well as the mechanisms responsible for the pro- and antitumor effects of multipotent mesenchymal stromal cells.