Tumor Cell-Derived Spermidine Promotes a Pro-Tumorigenic Immune Microenvironment in Glioblastoma via CD8⁺ T Cell Inhibition

Investigators demonstrated that the polyamine metabolite spermidine (SPD) was elevated in the glioblastoma tumor microenvironment. Exogenous administration of SPD drove tumor aggressiveness in an immune-dependent manner in pre-clinical mouse models via reduction of CD8+ T cell frequency and reduced cytotoxic function.