Abnormal polarization of macrophage-like cells in the peripheral blood of patients with glioma.

Glioma is a type of malignant tumor arising from glial cells of the brain or the spine. Circulation-derived macrophage infiltration is a characteristic of the glioma microenvironment. The polarization status of circulation-derived macrophages in patients with glioma remains unclear. Therefore, the present study aimed to evaluate the polarization status of circulation-derived macrophages in patients with glioma. A total of 40 patients with glioma and 38 healthy volunteers were recruited. The polarization status of macrophage-like cells in the peripheral blood of patients with glioma was evaluated. In addition, the associations between the polarization status of macrophage-like cells and glioma stage or the expression levels of the glioma tumor marker chitinase-3-like protein 1 (also termed YKL-40) were evaluated. The number of macrophage-like cells (CD115CD1cCD2CD15CD19CD14CD16CD11b) was higher in the peripheral blood of patients with glioma compared with that of healthy volunteers. There were fewer M1 macrophage-like cells, and more M2 macrophage-like cells were induced in the peripheral blood of patients with glioma compared with healthy controls. Specifically, the number of M2a/M2b macrophage-like cells increased, whereas that of M2c macrophage-like cells decreased in the peripheral blood of patients with glioma compared with healthy controls. The polarization status of macrophage-like cells in patients with glioma was not significantly associated with glioma stage or with the glioma marker YKL-40. Overall, the results of the present study revealed that the polarization status of macrophage-like cells in the peripheral blood of patients with glioma was abnormal, offering potential novel diagnostic and therapeutic targets, such as different macrophage subsets, for glioma.