Targeting polymorphonuclear myeloid-derived suppressor cells in the immunosuppressive tumor microenvironment for cancer immunotherapy.

Tumor-driven immune suppression is a critical mechanism by which cancer cells evade the host immune system, leading to tumor growth and metastasis. The tumor immune microenvironment contains a large population of immune-suppressing myeloid cells, which play a key role in tumor development and drug resistance to existing immunotherapy. Polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) are important components of the immunosuppressive microenvironment.