title: Effect of herbimycin A, an antagonist of tyrosine kinase, on bcr/abl oncoprotein-associated cell proliferations: abrogative effect on the transformation of murine hematopoietic cells by transfection of a retroviral vector expressing oncoprotein P210bcr/abl and preferential inhibition on Ph1-positive leukemia cell growth.
abstract: Herbimycin A, a benzoquinoid ansamycin antibiotic, was demonstrated to decrease intracellular phosphorylation by protein tyrosine kinase (PTK). In Philadelphia chromosome (Ph1)-positive leukemias such as chronic myelogenous leukemia (CML) and Ph1-positive acute lymphoblastic leukemia (ALL), both of which express bcr-abl fused gene products (P210bcr-abl or P190bcr-abl protein kinase) with augmented tyrosine kinase activities, herbimycin A markedly inhibited the in vitro growth of the Ph1-positive ALL cells and the leukemic cells derived from CML blast crisis. However, the same dose of herbimycin A did not inhibit in vitro growth of a broad spectrum of Ph1-negative human leukemia cells, and several other protein kinase antagonists also displayed no preferential inhibition. Furthermore, we demonstrated that herbimycin A has an antagonizing effect on the growth of transformed cells by a transfection of retroviral amphotrophic vector expressing P210bcr/abl into a murine interleukin (IL)-3-dependent myeloid FDC-P2 cell line. This inhibition was abrogated by the addition of sulfhydryl compounds, similar to the reaction previously described for Rous sarcoma virus transformation. The inhibitory effect of herbimycin A on the growth of Ph1-positive cells was associated with decreased bcr/abl tyrosine kinase activity, but no decrease of bcr-abl mRNA and protein, suggesting that the inactivation of bcr-abl tyrosine kinase activity by herbimycin A may be induced by its binding to the bcr-abl protein portion that is rich with sulfhydryl groups. The present study indicates that herbimycin A is a beneficial agent for the investigation of the role of the bcr-abl gene in Ph1-positive leukemias and further suggests that the development of agents inhibiting the bcr-abl gene product may offer a new therapeutic potential for Ph1-positive leukemias.
authors.affiliation: Third Department of Internal Medicine, School of Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Okabe
authors.forename: Y
authors.initials: Y
authors.lastname: Uehara
authors.forename: T
authors.initials: T
authors.lastname: Miyagishima
authors.forename: T
authors.initials: T
authors.lastname: Itaya
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: Y
authors.initials: Y
authors.lastname: Kuni-Eda
authors.forename: M
authors.initials: M
authors.lastname: Kurosawa
authors.forename: T
authors.initials: T
authors.lastname: Miyazaki
mesh_terms: D016227:Benzoquinones; D002455:Cell Division / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D016044:Fusion Proteins, bcr-abl / Q000037:antagonists & inhibitors* / Q000235:genetics; D005822:Genetic Vectors; D006801:Humans; D047029:Lactams, Macrocyclic; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy / Q000473:pathology*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D011809:Quinones / Q000494:pharmacology*; D012190:Retroviridae / Q000235:genetics*; D017828:Rifabutin / Q000031:analogs & derivatives; D013438:Sulfhydryl Compounds / Q000494:pharmacology; D014162:Transfection
chemical_list: D016227:Benzoquinones; D047029:Lactams, Macrocyclic; D011809:Quinones; D013438:Sulfhydryl Compounds; D017828:Rifabutin; C020754:herbimycin; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl