BEX4 and glioblastoma: In representative GBM cell lines, U87MG and U373MG, the delivery of radiation increased both the mRNA and protein expression of BEX1 and BEX4 in a time-dependent manner and 24 h after 6 Gy of IR was selected as the optimized condition for further experiments (Figure 2A,B and Supplementary Figure S1).