PRF1 and neoplasm: Among T cell subsets, EVs derived from CD8+ CTLs (CD8+ TExos) are functionally specialized to execute direct tumor cell killing.[256] Upon antigenic stimulation, CD8+ T cells secrete EVs enriched with cytotoxic effector proteins including perforin, granzyme B, and Fas ligand (FasL), which collectively induce both caspase‐dependent and extrinsic apoptotic pathways in target tumor cells.[261] These vesicles may partially reflect the antigen specificity of their parent T cells and selectively target tumor cells expressing cognate antigens, thereby minimizing off‐target effects.