The ALK domain of NPM-ALK contains kinase activity, which is responsible for the autophosphorylation of tyrosine residues of the oncogenic protein and phosphorylation of SH2-protein substrates.     ///    Model of inhibition of the NPM-ALK kinase activity by herbimycin A..     ///    Our results show that herbimycin A interferes with NPM-ALK and Akt pathways in SUDHL-1 cells.     ///    "NPM-ALK, Akt, and pAkt were down-regulated after 24 h of incubation with herbimycin A. "