CASP8 and glioblastoma: Most importantly, dying GBM satellites of microscopic tumor satellites was significantly increased in SBE4-TRAIL group (Fig. 5f, g, cleaved caspase-8: p < 0.001; Fig. 5h, i, cleaved caspase-3: p < 0.001; Additional file 6: Figure S6A–C, TRAIL: p < 0.001).