Although previous researches have revealed that transfecting SIRPα into U87MG, a kind of GBM cell lines, brings about tumor spreading and migration defects, [81] further observation and exploration are needed to determine the correlation between the malignant progression of astrocytoma cell lines and SIRPα expression (Fig. 2a). This evidence concerns the gene SIRPA and astrocytoma (excluding glioblastoma).