CSF1 and neoplasm: As previously mentioned, neutrophils are scarce in brain parenchyma; however, gliomas release various chemokines and cytokines (e.g., CSF-1, IL-8, IL-1β, CXCL1/2) that facilitate the recruitment of neutrophils within the TME.Cancer cells modulate the ratio of pro-tumor and anti-tumor neutrophils depending on the context (80).