CD81 and prostate cancer: In the prostate cancer cell line, LNCaP, depletion of extracellular glutamine, which also reduced S6 and 4E‐BP1 phosphorylation (Appendix Fig S7B, Fig EV4E), led to an increase in EV levels of Rab11a relative to CD81 (Appendix Figs S5D and H), while EV number and CD63 remained unchanged, but this increase was not significant relative to cell lysate protein mass (Figs 5B and G, and EV4E, Appendix Fig S7B’).