To further illustrate the effect of ER stress induced by SSD on cells, ICC showed that Caspase-12, Caspase-9, and Caspase-3 were expressed in the cytoplasm, and PARP was predominantly localized in the nuclei of four GBM cells after treatment with 9 and 15 μM SSD (Figure 4(a)). Here, CASP9 is linked to glioblastoma.