Reciprocal relationship between cancer stem cells and myeloid-derived suppressor cells: implications for tumor progression and therapeutic strategies

Recently, there has been an increased focus on cancer stem cells (CSCs) due to their resilience, making them difficult to eradicate. This resilience often leads to tumor recurrence and metastasis. CSCs adeptly manipulate their surroundings to create an environment conducive to their survival. In this environment, myeloid-derived suppressor cells (MDSCs) play a crucial role in promoting epithelial-mesenchymal transition and bolstering CSCs' stemness. In response, CSCs attract MDSCs, enhancing their infiltration, expansion and immunosuppressive capabilities. This interaction between CSCs and MDSCs increases the difficulty of antitumor therapy. In this paper, we discuss the interplay between CSCs and MDSCs based on current research and highlight recent therapeutic strategies targeting either CSCs or MDSCs that show promise in achieving effective antitumor outcomes. Cancer stem cells (CSCs) are a kind of tumor cell. These cells are hard to kill but contribute to tumor progression and metastasis. Myeloid-derived suppressor cells (MDSCs) exist in the tumor tissue and are unfriendly to the antitumor immune response. The interaction between CSCs and MDSCs has a protective effect on tumor progression. Therapeutic strategies targeting CSCs or MDSCs present potential to weaken the complex interaction between the two cell types. This review summarizes the current knowledge of CSCs-MDSCs interaction and offers fresh perspectives on the future development of antitumor therapies targeting CSCs or MDSCs.