How to Hit Mesenchymal Stromal Cells and Make the Tumor Microenvironment Immunostimulant Rather Than Immunosuppressive

Abstract

Experimental evidence indicates that mesenchymal stromal cells (MSCs) may regulate tumor microenvironment (TME). It is conceivable that the interaction with MSC can influence neoplastic cell functional behavior, remodeling TME and generating a tumor cell niche that supports tissue neovascularization, tumor invasion and metastasization. In addition, MSC can release transforming growth factor-beta that is involved in the epithelial–mesenchymal transition of carcinoma cells; this transition is essential to give rise to aggressive tumor cells and favor cancer progression. Also, MSC can both affect the anti-tumor immune response and limit drug availability surrounding tumor cells, thus creating a sort of barrier. This mechanism, in principle, should limit tumor expansion but, on the contrary, often leads to the impairment of the immune system-mediated recognition of tumor cells. Furthermore, the cross-talk between MSC and anti-tumor lymphocytes of the innate and adaptive arms of the immune system strongly drives TME to become immunosuppressive. Indeed, MSC can trigger the generation of several types of regulatory cells which block immune response and eventually impair the elimination of tumor cells. Based on these considerations, it should be possible to favor the anti-tumor immune response acting on TME. First, we will review the molecular mechanisms involved in MSC-mediated regulation of immune response. Second, we will focus on the experimental data supporting that it is possible to convert TME from immunosuppressive to immunostimulant, specifically targeting MSC.

MiR‐873 inhibition enhances gefitinib resistance in non‐small cell lung cancer cells by targeting glioma‐associated oncogene homolog 1

“…During angiogenesis, tumor growth changes from slow to rapid; angiogenesis is the key step to facilitate this transformation. Inhibition of angiogenesis can obviously control tumor growth and metastasis . In this study, we found that miR‐873 suppression conspicuously enhanced the viability and growth of PC9 cells treated with gefitinib.…”

“…Inhibition of angiogenesis can obviously control tumor growth and metastasis. [45][46][47][48][49] In this study, we found that miR-873 suppression conspicuously enhanced the viability and growth of PC9 cells treated with gefitinib. Moreover, the inhibition of miR-873 increased angiogenesis.…”

Meflin-Positive Cancer-Associated Fibroblasts Inhibit Pancreatic Carcinogenesis

“…Thus, the biology of CAFs, including their origins, specific markers, functions, and clinical relevance, has gained increasing research interest in recent years (3)(4)(5)(6)(7)(8). Clinical trials of therapeutics that target CAFs are also emerging, with investigations on the underlying mechanisms (4,8,19,20).…”

Manipulated Mesenchymal Stem Cells Applications in Neurodegenerative Diseases

“…Although MSCs from different sources exert their immunomodulatory functions in different ways, the fundamental mechanism is shared among them. Both cell-cell contact and secreted molecules are involved in immunomodulatory properties mediated by MSCs (25,30,31).…”