Immune Cells in the Tumor Microenvironment of Soft Tissue Sarcomas

Simple Summary Soft tissue sarcomas represent a large heterogeneous group of malignant neoplasms that are characterized by a poor disease outcome and being poorly studied. Recently, more and more studies have been directed to the role of tumor microenvironment components in establishing the aggressive potential of the tumor. Many antitumor drugs, in addition to their direct effect on tumor cells, modify the tumor microenvironment; in particular, they act on the immune component, which may be the reason for their effectiveness in soft tissue sarcoma. Immune cells themselves are now considered as promising antitumor strategies for the treatment of soft tissue sarcomas. Understanding the mechanisms of interaction between tumor cells and immune cells in different types of soft tissue sarcomas will allow us to divide patients into those for whom immunotherapy will be highly effective and those for whom this type of treatment will be ineffective.Abstract Soft tissue sarcomas (STSs) are a rare heterogeneous group of malignant neoplasms characterized by their aggressive course and poor response to treatment. This determines the relevance of research aimed at studying the pathogenesis of STSs. By now, it is known that STSs is characterized by complex relationships between the tumor cells and immune cells of the microenvironment. Dynamic interactions between tumor cells and components of the microenvironment enhance adaptation to changing environmental conditions, which provides the high aggressive potential of STSs and resistance to antitumor therapy. Today, active research is being conducted to find effective antitumor drugs and to evaluate the possibility of using therapy with immune cells of STS. The difficulty in assessing the efficacy of new antitumor options is primarily due to the high heterogeneity of this group of malignant neoplasms. Studying the role of immune cells in the microenvironment in the progression STSs and resistance to antitumor therapies will provide the discovery of new biomarkers of the disease and the prediction of response to immunotherapy. In addition, it will help to initially divide patients into subgroups of good and poor response to immunotherapy, thus avoiding wasting precious time in selecting the appropriate antitumor agent.