CASP3 and triple-negative breast carcinoma: In patients with triple-negative breast cancer (TNBC), small extracellular vesicles (sEVs) in the plasma, especially exosomes derived from tumor cells (TEXs), when they enter T cells, induce the release of cyt c and Smac from the mitochondria and activate the cleavage of caspase-3 and PARP in the cytoplasm, thereby promoting T-cell dysfunction and leading to tumor progression [33].