Inhibition of exosomal Bcl-xL cleavage attenuates the proliferation of MM and ALCL cell lines. Flow cytometric analysis of fluorescein diacetate–positive RPMI, OPM2, SupM2, or Mac2a cells after 48 hours of incubation with L88-Bcl-xL WT exosomes that were preincubated with the caspase inhibitor zVAD.fmk (mean ± SD, n = 3, *P < .05, **P < .01).