IRF8 is a critical factor in myeloid cell development and acts as a negative regulator of MDSCs.208 Within the tumor microenvironment, tumor cells and infiltrating stromal cells release cytokines like G-CSF and GM-CSF, which activate the Janus kinase (JAK)/STAT signaling pathway and suppress IRF8 expression in MDSCs. This evidence concerns the gene CSF3 and neoplasm.