Inhibition of tyrosine kinase activity induces caspase-dependent apoptosis in anaplastic large cell lymphoma with NPM-ALK (p80) fusion protein.
OBJECTIVE
The t(2;5)(p23;q35) translocation creates a fusion gene NPM-ALK (p80) that encodes a product with tyrosine kinase activity believed to play an important role in development of anaplastic large cell lymphoma (ALCL). Our study was aimed to analyze tyrosine kinase activity and phosphotyrosine in ALCLs. We were also interested in determining the effect of tyrosine kinase inhibitors on survival of ALCL.


METHODS
Eleven cases of ALCL and three ALCL cell lines with t(2;5)(Karpas-299, SUPM2, SU-DHL-1) and 10 Hodgkin's disease (HD) samples were stained with anti-phosphotyrosine antibody. The tyrosine kinase activity, p80 phosphorylation, and the apoptotic effects of two tyrosine kinase inhibitors, herbimycin A and STI-571, were determined on ALCL cell lines.


RESULTS
Herbimycin A had showed both a time- and dose-dependent apoptotic effect on all three cell lines, while STI-571 demonstrated a minimal effect. Following herbimycin A treatment, a decrease in tyrosine kinase activity in the ALCL cell lines and inhibition in NPM-ALK (p80) autophosphorylation was demonstrated by immunoprecipitation and Western blotting. Herbimycin A-induced apoptosis was accompanied by caspase-3 activation. Furthermore, apoptosis induced by herbimycin A was blocked by both z-VAD-FMK and z-DEVD-FMK, suggesting a critical role of caspases.


CONCLUSIONS
These findings indicate that tyrosine kinase activity is a common characteristic of ALCLs and necessary for ALCL cell survival. These findings further suggest that therapies targeting tyrosine kinases, including p80, may have clinical utility.
Ergin
M
M
Department of Pathology, Loyola University Medical Center, Maywood, IL 60153, USA.
Denning
M F
MF
Izban
K F
KF
Amin
H M
HM
Martinez
R L
RL
Saeed
S
S
Alkan
S
S
D000077548:Anaplastic Lymphoma Kinase; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D001549:Benzamides; D016227:Benzoquinones; D020169:Caspases / Q000494:pharmacology*; D002889:Chromosomes, Human, Pair 2; D002895:Chromosomes, Human, Pair 5; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006689:Hodgkin Disease / Q000473:pathology; D006801:Humans; D000068877:Imatinib Mesylate; D007150:Immunohistochemistry; D047029:Lactams, Macrocyclic; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology*; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D010879:Piperazines / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology; D011809:Quinones / Q000494:pharmacology; D020794:Receptor Protein-Tyrosine Kinases; D017828:Rifabutin / Q000031:analogs & derivatives; D014178:Translocation, Genetic; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000970:Antineoplastic Agents; D001549:Benzamides; D016227:Benzoquinones; D004791:Enzyme Inhibitors; D047029:Lactams, Macrocyclic; D015514:Oncogene Proteins, Fusion; D010879:Piperazines; D011743:Pyrimidines; D011809:Quinones; D017828:Rifabutin; C020754:herbimycin; D000068877:Imatinib Mesylate; C107023:p80(NPM-ALK) protein; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D020169:Caspases