sentences: ).These activities may result in further polarization of tumor-associated macrophages, conversion of fibroblasts into tumor-promoting cancer-associated fibroblasts, conversion of dendritic cells into tumor-associated DCs and activation of pro-tumorigenic functions of immature myeloid cells - Myeloid-derived Suppressor Cells (MDSC).TLR signaling has been linked to accumulation and function of MDSC at the site of tumor and it also allows mesenchymal stromal cells to counter NK cell-mediated anti-tumor immunity.