To further ascertain the believability of the IRGP signature in normal human astrocytes and low-grade glioma cells (WHO Grade III, astrocytoma), we performed western blotting analysis and qRT-PCR to investigate the transcription and protein expression levels of four selected IRGs (EGFR, SLIT1, ADRB2, and MSR1) in these cell lines. This evidence concerns the gene SLIT1 and central nervous system cancer.