Immunostaining showed that CELSR2 was positive in GFAP-positive astrocytes of both CP-H122 and U87 MG cell lines, but a rare detectable CELSR2-positive signal was found in the CELSR2-shRNA treated U87 MG cell lines and CELSR2-shRNA treated Grade 3 primary glioma cells (Fig. 2A, Supplementary Fig. 2B). Here, GFAP is linked to glioma.