Although it has been postulated that brain cancer cells distribute aquaporins (AQPs) between cells via EVs [43, 44], as occurs in the kidney where AQP1 and aquaporin-2 (AQP2) have been found in urinary exosomes, the presence of an AQP, namely AQP4, in EV cargoes derived from glioma cells has been reported here for the first time. The gene discussed is AQP2; the disease is brain cancer.