CELSR2 and central nervous system cancer: To investigate whether CELSR2 KD influences cell apoptosis, cultured cells were subjected to FACS analysis, showing no significant differences of PI and Annexin V double-positive population between the CELSR2-KD group and the control group (Fig. 2H; Supplementary Fig. 2F, G), suggesting that CELSR2 is not involved in apoptosis of U87 MG cells or Grade 3 primary glioma cells.