Fig 1: Polyamine-dependent hypusination of eIF5A is required for the induction of adipocyte lipolysis.(A) Spermidine is the substrate for the 2-step post-translational modification of eIF5A. (B) KPC CM induces hypusination of eIF5A in adipocytes. (C, D) Inhibition of eIF5A hypusination with AG/GC7 (AG=aminoguanidine, a GC7 stabilizer) prevents hypusination and lipolysis in adipocytes exposed to KPC CM (n = 3). (E) Schematic representation of cancer EVs’ delivery of polyamines to the adipocytes. (F) EV markers TSG101 and CD9, but not hypusine or eIF5A, can be detected in purified EVs. (G) Representative images of fluorescently labeled EVs taken up by adipocytes 24 hours post-incubation. (H, I) KCP EVs promote lipolysis and eIF5A hypusination in adipocytes to a similar extent of the complete KPC CM (n = 3). (J, K) Inhibition of eIF5A hypusination with AG/GC7 prevents hypusination and lipolysis induced by KPC’s EVs (n = 3). Data shown as mean ± SD. * p<0.05, ** p<0.01, *** p<0.001, 1-way ANOVA-Tukey’s post-test or unpaired t test (C).