Model of inhibition of the NPM-ALK kinase activity by herbimycin A.
Anaplastic large cell lymphoma (ALCL) exhibiting the t(2;5) translocation is characterized by the resulting expression of the oncogenic fusion protein nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) gene product. 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. Herbimycin A is a general protein tyrosine kinase inhibitor active as an antiproliferative compound against different types of mammalian cells. Herbimycin A inhibited the NPM-ALK-associated autophosphorylating activity in an in vitro cell-free kinase assay. The inhibition was specific when tested against other kinase inhibitors and extended to other cell lines derived from t(2;5)-ALCL. SUDHL-1 cells showed increasing percentage of cells in G(1) after 18 h of incubation with a dose of herbimycin A. NPM-ALK, Akt, and pAkt were down-regulated after 24 h of incubation with herbimycin A. Apoptosis was observed only if the dose of inhibitor was given every 12 h for prolonged time. Our results show that herbimycin A interferes with NPM-ALK and Akt pathways in SUDHL-1 cells. It seems that prolonged inhibition of these biochemical pathways may lead to cell cycle arrest and apoptosis. This study supports the idea of investigating protein kinase inhibitors as therapeutic compounds for t(2;5)-ALCL.
Turturro
Francesco
F
Human Gene Therapy Research Institute, John Stoddard Cancer Center, Des Moines, Iowa 50309, USA. turturfm@ihs.org
Arnold
Marilyn D
MD
Frist
Audrey Y
AY
Pulford
Karen
K
D000077548:Anaplastic Lymphoma Kinase; D017209:Apoptosis / Q000187:drug effects; D016227:Benzoquinones; D015153:Blotting, Western; D002453:Cell Cycle / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D007211:Indoles; D047029:Lactams, Macrocyclic; D016403:Lymphoma, Large B-Cell, Diffuse / Q000378:metabolism*; D015514:Oncogene Proteins, Fusion / Q000037:antagonists & inhibitors / Q000378:metabolism; D010766:Phosphorylation; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011809:Quinones / Q000494:pharmacology*; D020794:Receptor Protein-Tyrosine Kinases; D017828:Rifabutin / Q000031:analogs & derivatives; D014407:Tumor Cells, Cultured / Q000166:cytology / Q000187:drug effects / Q000201:enzymology
D016227:Benzoquinones; D004791:Enzyme Inhibitors; D007211:Indoles; D047029:Lactams, Macrocyclic; D015514:Oncogene Proteins, Fusion; D011809:Quinones; D017828:Rifabutin; C007293:DAPI; C020754:herbimycin; D011065:Poly(ADP-ribose) Polymerases; C107023:p80(NPM-ALK) protein; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases