Microvesicles were isolated from three medulloblastoma cell lines (a, D384, b, D425 and c, D458), one melanoma (d, Yumel 0106), two GBMs (e, 20/3 and f, 11/5) and two normal fibroblasts (g, HF19 and h, HF27) and measured with Nanoparticle Tracking Analysis (NanoSight). The number of particles per cell per 48 h is shown on the y axis, and the size distribution (particle diameter) on the x axis. The sum refers to the total number of particles released per cell over 48 h and the exoRNA refers to the total microvesicle RNA yield per 1×106 cells per 48 h. The results are presented as the mean ± s.e.m. (n = 3).