Tumor Associated Mesenchymal Stromal Cells Show Higher Immunosuppressive and Angiogenic Properties Compared to Adipose Derived MSCs.

Background: Differentiation, migratory properties and availability of Mesenchymal Stromal Cells (MSC) have become an important part of biomedical research. However, the functional heterogeneity of cells derived from different tissues has hampered providing definitive phenotypic markers for these cells. Objective: To characterize and compare the phenotype and cytokines of adipose derived MSCs (AD-MSCs) and tumoral-MSCs (T-MSCs) isolated from mammary tumors of BALB/c mice. Methods: Immunophenotyping and in vitro differentiation tests were used for MSC characterization. Cytokine and enzyme profiles were assessed using ELISA and Realtime PCR, respectively. Results: T-MSCs expressed significantly higher levels of HLADR (p=0.04). Higher levels of PGE2 and COX-2 enzyme were also observed in TMSCs (p=0.07 and p=0.00, respectively). Additionally, T-MSCs expressed higher levels of iNOS and MMP9 (p=0.01 and p=0.01, respectively). T-MSCs were also able to induce higher levels of proliferation and migration of HUVEC endothelial cells in wound scratch assay compared to AD-MSCs (p=0.015). Conclusion: Functional differences showed by the surface markers of MSCs, cytokine and enzyme production indicate the effect of different microenvironments on MSCs phenotype and function.