SMPD3 and cancer: Among those, neutral sphingomyelinase 2 (nSMase2) [15,16], phosphorylated synaptosome-associated protein 23 (SNAP23) [17,18] and Ras-related RAB proteins (RAB27A/RAB27B) [19,20,21] regulate sEV secretion from different cancer cells like breast cancer [15,16], hepatocellular carcinoma (HCC) [17,18], and colorectal cancer [17,20].