Interestingly, the inhibition of exosome secretion, observed not only with the shRNA of Alix but also the shRNA of Rab27b and an inhibitor of sphingomyelinase (GW4869), suppressed cancer phenotypes of exosome–secreting cells, suggesting that appropriate secretion of exosomes contributes to the maintenance of cancer phenotypes. Here, PDCD6IP is linked to cancer.