RAB27A and neoplasm: Intraluminal vesicles formed in LE compartment can also be secreted as exosomes19 and to investigate the role of exosome-specific clearance, we knockdown Rab27a, a well-established regulator of exosome secretion in tumour cells40 and used a small inhibitor of sphingomyelin phosphodiesterase 3 pathway, 3-O-Methyl-sphingomyelin41.