TGFB1 and central nervous system cancer: Moreover, the result displayed that TAM marker (CCL2), macrophage M1 marker (PTGS2), macrophage M2 markers (CD163, VSIG4, and MS4A4A), neutrophil marker (ITGAM), and Treg marker (TGFB1) were observably positively associated with the expression level of TIMP1 in GBM (Table 4), which suggested that TIMP1 plays a vital role in the glioma immune microenvironment.