Miyazaki et al. [39] found that cancer-derived EVs contain EBAG9 protein, which cooperates with transmembrane 9 superfamily member 1 (TM9SF1) to promote epithelial-to-mesenchymal transition (EMT) of prostate cancer cells, inhibits the cytotoxicity of T cells, and negatively regulates tumor surveillance in host cells to promote tumor development. The gene discussed is TM9SF1; the disease is prostate cancer.