We found that the mRNA expression ratio of ITSN1-S/ITSN1-L in GBM cell lines was higher than that in immortalized astrocytes (Fig. 1K), and that the expression ratio of ITSN1-S/ITSN1-L increased with glioma grading by analysis of TCGA database (Fig. 1L). Here, ITSN1 is linked to central nervous system cancer.