Astrocytes help metastatic cells achieve immune escape: signal transducer and activator of transcription (STAT3)-positive astrocytes amplify the number of supportive CD74 + microglial/macrophages in the tumor vicinity and restrict CD8 + T cells from penetrating the tumor microenvironment (TME) as a barrier (Fig. 1C) [26]. Here, CD8A is linked to neoplasm.