SDC1 and glioblastoma: Upregulated EV markers included syndecan (which co-expresses with syntenin for exosome biogenesis),138 tetraspanin-4 (a migrasome-specific marker), CD63 (an exosome marker), and lysosomal LAMP2, which modulates exosomal cargo.139,140 Studies by Hallal et al revealed that EVs released by glioblastoma cells promote SASP activation in normal astrocytes, suggesting that stress-induced exosomal cargo may contribute to treatment resistance.141 EVs produced by glioblastoma under stress conditions induced by treatment contain numerous proteins involved in splicing machinery, such as HNRNPs.