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Yoshimasa Uehara - One of the best experts on this subject based on the ideXlab platform.

  • Herbimycin a a tyrosine kinase inhibitor impairs hypercalcemia associated with a human squamous cancer producing interleukin 6 in nude mice
    Journal of Bone and Mineral Research, 2009
    Co-Authors: Yoshimasa Uehara, Gregory R Mundy, Maria Niewolna, Paul J Williams, Keiji Moriyama, Mark Dallas, Toshiyuki Yoneda
    Abstract:

    Interleukin-6 (IL-6) is a multifunctional cytokine that is produced not only by a variety of normal cells but also by cancer cells. IL-6 produced by cancer cells stimulates the proliferation of these cancer cells in an autocrine/ paracrine manner and causes paraneoplastic syndromes including hypercalcemia, cachexia, and leukocytosis. We have reported previously that a human oral squamous cancer associated with hypercalcemia produces large amounts of IL-6, that animals bearing this cancer exhibit elevated levels of plasma IL-6, and that neutralizing antibodies to human IL-6 reverse hypercalcemia in tumor-bearing animals, indicating an important role of IL-6 in the hypercalcemia in this model. Because these cancer cells overexpress epidermal growth factor receptors (EGFR) with intrinsic tyrosine kinase (TK) activity similar to many other squamous cancers, we examined the effects of Herbimycin A, a tyrosine kinase inhibitor, on IL-6 production and hypercalcemia in animals bearing this cancer to develop a new approach to treat the hypercalcemia associated with malignancy. Intraperitoneal administration (once a day for 2 days) of Herbimycin A to cancer-bearing hypercalcemic mice reduced the plasma levels of human IL-6 and impaired the hypercalcemia. During 2-day treatment with Herbimycin A, no changes were observed in tumor size. Of interest, plasma levels of mouse, but not human, soluble IL-6 receptors were also elevated. However, Herbimycin A showed no effects on plasma levels of mouse soluble IL-6 receptors. Herbimycin A suppressed the tyrosine autophosphorylation of EGFR and IL-6 mRNA expression and production, all of which were stimulated by EGF. The data raise the possibility that TK inhibitors may be potential mechanism-based therapeutic agents for the treatment of hypercalcemia associated with squamous cancers which overexpress EGFR.

  • Use and selectivity of Herbimycin A as inhibitor of protein-tyrosine kinases.
    Methods in Enzymology, 2004
    Co-Authors: Yoshimasa Uehara, Hidesuke Fukazawa
    Abstract:

    Publisher Summary This chapter discusses the use and selectivity of Herbimycin A as inhibitor of protein-tyrosine kinases. Protein-tyrosine phosphorylation is one of the basic mechanisms of signal transduction for cell growth and differentiation. Specific inhibitors of protein tyrosine kinases, therefore, may provide useful means for examining the role of tyrosine phosphorylation in a variety of cellular events. Herbimycin A induces inactivation of v-src tyrosine kinase and reduces cellular phosphotyrosine content in RSV-transformed cells. Because of restricted water solubility of Herbimycin A, the preparation of concentrated stock solutions can best be done in an organic solvent such as dimethyl sulfoxide (DMSO) or methanol. The concentration required to reverse morphology varies among cells. The beginning of morphological changes can usually be observed within several hours, and is preceded by a reduction in tyrosine kinase activity.

  • Herbimycin a induces g1 arrest through accumulation of p27 kip1 in cyclin d1 overexpressing fibroblasts
    Biochemical and Biophysical Research Communications, 2000
    Co-Authors: Naoko Endo, Yoshimasa Uehara, Kazuo Umezawa, Etsu Tashiro, Manabu Kawada, Yuichiro Doki, Bernard I Weinstein, Masaya Imoto
    Abstract:

    The ansamycin antibiotic Herbimycin A is a potent tyrosine kinase inhibitor and reduces the growth rate of various types of mammalian cells. When quiescent Rat6 fibroblast cells were treated with Herbimycin A, serum-induced expression of cyclin D1 was inhibited, and this was associated with inhibition of G1 phase progression. However, Herbimycin A also inhibited serum-induced G1 progression in derivatives of the Rat6 fibroblast cell line that stably overexpress a human cyclin D1 cDNA (R6ccnD1#4 cells), without affecting the expression levels of G1 cyclins. We found that Herbimycin A prevented serum-induced downregulation of the cyclin-dependent kinase inhibitor p27Kip1, thereby leading to inactivation of the protein kinase activity of CDK2. These results suggest that Herbimycin A inhibits a tyrosine kinase(s) that plays a role in degradation of the p27Kop1 protein.

  • Effect of Herbimycin A on Tyrosine Kinase Receptors and Platelet Derived Growth Factor (PDGF)-Induced Signal Transduction
    Biological & pharmaceutical bulletin, 1998
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    Herbimycin A is widely used as an inhibitor of Src family protein tyrosine kinases but is also reported to induce the downregulation of epidermal growth factor (EGF) receptor number in A431 cells without inhibiting its tyrosine kinase activity. To determine the specificity of the receptor downregulation, we examined its effect on a variety of cell lines which express different levels of EGF receptor and on other tyrosine kinase receptors. Long-term Herbimycin A treatment decreased the amounts of all the tyrosine kinase receptors examined in a dose-dependent manner. It also reduced ligand-stimulated receptor autophosphorylation in accordance with the reduction in the receptor level. Herbimycin A inhibited platelet derived growth factor (PDGF)-induced tyrosine phosphorylation of cellular proteins and DNA synthesis in NIH3T3 cells but did not affect the serum-stimulated DNA synthesis. PDGF-induced tyrosine phosphorylation and activation of c-Src was inhibited but the protein level of c-Src was not reduced by Herbimycin A. The reduced level of c-Src kinase activity correlated with the levels of both PDGF receptor and DNA synthesis. These results indicate that the Herbimycin A treatment selectively downregulates receptor tyrosine kinases, independent of the number of receptors, and suggest that c-Src is to some degree involved in the selective inhibition of PDGF-induced mitogenesis by Herbimycin A.

  • in vivo antitumor activity of Herbimycin a a tyrosine kinase inhibitor targeted against bcr abl oncoprotein in mice bearing bcr abl transfected cells
    Leukemia Research, 1994
    Co-Authors: Mihiro Okabe, Yoshimasa Uehara, Toshiyuki Itaya, Takayuki Noshima, Yasuyuki Kunieda, Mitsutoshi Kurosawa
    Abstract:

    Herbimycin A, a benzoquinoid ansamycin antibiotic, has been shown to reverse the oncogenic phenotype of p60v-src transformed cells because of the inhibition of src protein tyrosine kinase. We previously demonstrated that Herbimycin A displayed antitumor activity on the in vitro growth of Philadelphia chromosome-positive leukemia cells and BCR/ABL-transfected murine hematopoietic FDC-P2 cells through the inhibition of BCR/ABL protein tyrosine kinase. In this study, the transformed FDC-P2 cells were demonstrated to be tumorigenic in syngeneic DBA/2 mice. The intraperitoneal (i.p.) injection of the transformed tumor cells into DBA/2 mice induced infiltrations of abdominal organs, and then all of the mice died within time periods proportional to the cell numbers of inoculation. In mice that received an i.p. inoculation with greater than 1 x 10(5) cells, in vivo administration of Herbimycin A by i.p. injection inhibited tumor formation and significantly prolonged survival time, and further, in mice inoculated with 1 x 10(4) cells, Herbimycin A completely suppressed the in vivo growth of transformant FDC-P2 cells and brought about a complete remission. The present study revealed the in vivo efficacy of Herbimycin A in mice bearing BCR/ABL-transfected cells.

Hidesuke Fukazawa - One of the best experts on this subject based on the ideXlab platform.

  • Use and selectivity of Herbimycin A as inhibitor of protein-tyrosine kinases.
    Methods in Enzymology, 2004
    Co-Authors: Yoshimasa Uehara, Hidesuke Fukazawa
    Abstract:

    Publisher Summary This chapter discusses the use and selectivity of Herbimycin A as inhibitor of protein-tyrosine kinases. Protein-tyrosine phosphorylation is one of the basic mechanisms of signal transduction for cell growth and differentiation. Specific inhibitors of protein tyrosine kinases, therefore, may provide useful means for examining the role of tyrosine phosphorylation in a variety of cellular events. Herbimycin A induces inactivation of v-src tyrosine kinase and reduces cellular phosphotyrosine content in RSV-transformed cells. Because of restricted water solubility of Herbimycin A, the preparation of concentrated stock solutions can best be done in an organic solvent such as dimethyl sulfoxide (DMSO) or methanol. The concentration required to reverse morphology varies among cells. The beginning of morphological changes can usually be observed within several hours, and is preceded by a reduction in tyrosine kinase activity.

  • Effect of Herbimycin A on Tyrosine Kinase Receptors and Platelet Derived Growth Factor (PDGF)-Induced Signal Transduction
    Biological & pharmaceutical bulletin, 1998
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    Herbimycin A is widely used as an inhibitor of Src family protein tyrosine kinases but is also reported to induce the downregulation of epidermal growth factor (EGF) receptor number in A431 cells without inhibiting its tyrosine kinase activity. To determine the specificity of the receptor downregulation, we examined its effect on a variety of cell lines which express different levels of EGF receptor and on other tyrosine kinase receptors. Long-term Herbimycin A treatment decreased the amounts of all the tyrosine kinase receptors examined in a dose-dependent manner. It also reduced ligand-stimulated receptor autophosphorylation in accordance with the reduction in the receptor level. Herbimycin A inhibited platelet derived growth factor (PDGF)-induced tyrosine phosphorylation of cellular proteins and DNA synthesis in NIH3T3 cells but did not affect the serum-stimulated DNA synthesis. PDGF-induced tyrosine phosphorylation and activation of c-Src was inhibited but the protein level of c-Src was not reduced by Herbimycin A. The reduced level of c-Src kinase activity correlated with the levels of both PDGF receptor and DNA synthesis. These results indicate that the Herbimycin A treatment selectively downregulates receptor tyrosine kinases, independent of the number of receptors, and suggest that c-Src is to some degree involved in the selective inhibition of PDGF-induced mitogenesis by Herbimycin A.

  • conversion of epidermal growth factor egf into a stimulatory ligand for a431 cell growth by Herbimycin a by decreasing the level of expression of egf receptor
    Biochemical Journal, 1994
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    We examined effect of the tyrosine kinase inhibitor Herbimycin A on A431 human epidermoid carcinoma cells which over-express epidermal growth factor (EGF) receptor. Herbimycin A inhibited the autophosphorylation of EGF-stimulated receptors in intact cells both time- and dose-dependently. The inhibition was found to be due to a decrease in the level of expression of the receptor amount, because Herbimycin A equally decreased the receptor quantity and EGF-stimulated receptor kinase activity in intact cells, but did not exhibit a direct inhibitory effect on EGF receptor kinase activity in vitro. The decrease of the level of EGF receptor was also confirmed by 125I-EGF binding to Herbimycin A-treated cells, and Scatchard analysis showed that the decrease in the receptor number occurred in the major population of the low-affinity binding ones, whereas the number with high-affinity binding was unaffected. Interestingly, although the proliferation of A431 cells was inhibited by EGF, Herbimycin A converted EGF into a stimulatory ligand for cell growth, as determined by both cell number and DNA synthesis. These findings indicated that Herbimycin A decreased the level of expression of EGF receptor by a mechanism other than inactivation of the receptor kinase and reversed the transformed phenotype of A431 cells to a normal one in the proliferative response to EGF.

  • Labeling of v-Src and BCR-ABL tyrosine kinases with [14C]Herbimycin A and its use in the elucidation of the kinase inactivation mechanism
    FEBS Letters, 1994
    Co-Authors: Hidesuke Fukazawa, Yuko Murakami, Masa Hamada, Yoshimasa Uehara, Satoshi Mizuno, Tomio Takeuchi
    Abstract:

    Abstract The ansamycin antibiotic, Herbimycin A, selectively inactivates cytoplasmic tyrosine kinases, most likely by binding irreversibly to the reactive SH group(s) of kinases. To further investigate the mechanism of Herbimycin A action, we attempted to label tyrosine kinases with [14C]Herbimycin A. p60v-src and p2 10BCR-ABL in immune complexes were labeled with [14C]Herbimycin A, demonstrating that the antibiotic binds directly to tyrosine kinases. Digestion of [14C]Herbimycin A-labeled p60v-src with Staphylococcus taureus V8 protease revealed that the Herbimycin A binding site is within the C-terminal 26-kDa fragment of p60v-src, which contains the tyrosine kinase domain. Herbimycin A treatment inhibited labeling of p60v-src by [14]C]fluorosulfonylbenzoyl adenosine, an affinity labeling reagent of nucleotide binding sites, indicating that Herbimycin A-modified p60v-src cannot interact with ATP. The results suggest that Herbimycin A inactivates tyrosine kinases by binding directly to the kinase domain, thereby inhibiting access to ATP.

  • specific inhibition of cytoplasmic protein tyrosine kinases by Herbimycin a in vitro
    Biochemical Pharmacology, 1991
    Co-Authors: Hidesuke Fukazawa, Yuko Murakami, Satoshi Mizuno, C Yamamoto, Yoshimasa Uehara
    Abstract:

    Abstract Herbimycin A is an antibiotic which reverses transformation caused by various src related oncogenes. The reversion of transformation is restricted to cells transformed by tyrosine kinase coding oncogenes, and accompanies a decrease in kinase activity of the oncogene products. We have shown in vitro that Herbimycin A directly inactivates p60 v-src kinase by conjugating with SH group(s) of the kinase, raising the possibility that the molecular target of the antibiotic for reversion of v- src transformation is the p60 v-src itself. To investigate the relevance of its in vitro tyrosine kinase inactivating activity to in vivo transformation reversing activity, we examined the specificity of Herbimycin A for inhibition of cAMP-dependent kinase, protein kinase C and p210 bcr-abl tyrosine kinase in vitro . Herbimycin A had no inhibitory effect on the activities of cAMP-dependent kinase or protein kinase C, whereas the SH-reagent N -(9-acridinyl)maleimide, which inactivates p60 v-crc in vitro by a mechanism similar to that of Herbimycin A, blocked the two serine/threonine kinases. On the other hand, the activity of p210 bcr-abl tyrosine kinase was inhibited by Herbimycin A treatment. The results indicate that Herbimycin A specifically binds to reactive SH group(s) of cytoplasmic protein tyrosine kinases, and confer the biochemical basis for its selectivity in reversing cell transformation.

Yuko Murakami - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Herbimycin A on Tyrosine Kinase Receptors and Platelet Derived Growth Factor (PDGF)-Induced Signal Transduction
    Biological & pharmaceutical bulletin, 1998
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    Herbimycin A is widely used as an inhibitor of Src family protein tyrosine kinases but is also reported to induce the downregulation of epidermal growth factor (EGF) receptor number in A431 cells without inhibiting its tyrosine kinase activity. To determine the specificity of the receptor downregulation, we examined its effect on a variety of cell lines which express different levels of EGF receptor and on other tyrosine kinase receptors. Long-term Herbimycin A treatment decreased the amounts of all the tyrosine kinase receptors examined in a dose-dependent manner. It also reduced ligand-stimulated receptor autophosphorylation in accordance with the reduction in the receptor level. Herbimycin A inhibited platelet derived growth factor (PDGF)-induced tyrosine phosphorylation of cellular proteins and DNA synthesis in NIH3T3 cells but did not affect the serum-stimulated DNA synthesis. PDGF-induced tyrosine phosphorylation and activation of c-Src was inhibited but the protein level of c-Src was not reduced by Herbimycin A. The reduced level of c-Src kinase activity correlated with the levels of both PDGF receptor and DNA synthesis. These results indicate that the Herbimycin A treatment selectively downregulates receptor tyrosine kinases, independent of the number of receptors, and suggest that c-Src is to some degree involved in the selective inhibition of PDGF-induced mitogenesis by Herbimycin A.

  • accelerated degradation of 160 kda epidermal growth factor egf receptor precursor by the tyrosine kinase inhibitor Herbimycin a in the endoplasmic reticulum of a431 human epidermoid carcinoma cells
    Biochemical Journal, 1994
    Co-Authors: Yuko Murakami, S Mizuno, Y Uehara
    Abstract:

    The effect of Herbimycin A on the biosynthesis of epidermal growth factor (EGF) receptor was examined in human epidermoid carcinoma A431 cells. Cells were pulse-labelled with [35S]methionine, and EGF receptor biosynthesis was quantified by immunoprecipitation using a monoclonal anti-(EGF receptor) antibody. In the presence of Herbimycin A, an immature 160 kDa EGF receptor precursor accumulated in 1 h and disappeared completely in 4 h. Pulse-labelled 160 kDa receptor precursor in the absence of Herbimycin A, however, was converted normally into a 170 kDa one by chase with Herbimycin A. Herbimycin A affected neither the synthesis of the secreted form of EGF receptor devoid of cytoplasmic domain, nor that of the transferrin receptor in A431 cells. The Herbimycin A-induced degradation of 160 kDa EGF receptor precursor was not inhibited by an inhibitor of lysosomal enzymes, NH4Cl. Endoglycosidase H digestion of the 160 kDa precursor converted it into the deglycosylated 130 kDa precursor peptide. These results suggested that Herbimycin A selectively acted on the EGF receptor precursor during the synthesis of the 160 kDa form, probably on the cytoplasmic domain, to form an aberrant molecule which was subjected to rapid degradation in the endoplasmic reticulum.

  • conversion of epidermal growth factor egf into a stimulatory ligand for a431 cell growth by Herbimycin a by decreasing the level of expression of egf receptor
    Biochemical Journal, 1994
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    We examined effect of the tyrosine kinase inhibitor Herbimycin A on A431 human epidermoid carcinoma cells which over-express epidermal growth factor (EGF) receptor. Herbimycin A inhibited the autophosphorylation of EGF-stimulated receptors in intact cells both time- and dose-dependently. The inhibition was found to be due to a decrease in the level of expression of the receptor amount, because Herbimycin A equally decreased the receptor quantity and EGF-stimulated receptor kinase activity in intact cells, but did not exhibit a direct inhibitory effect on EGF receptor kinase activity in vitro. The decrease of the level of EGF receptor was also confirmed by 125I-EGF binding to Herbimycin A-treated cells, and Scatchard analysis showed that the decrease in the receptor number occurred in the major population of the low-affinity binding ones, whereas the number with high-affinity binding was unaffected. Interestingly, although the proliferation of A431 cells was inhibited by EGF, Herbimycin A converted EGF into a stimulatory ligand for cell growth, as determined by both cell number and DNA synthesis. These findings indicated that Herbimycin A decreased the level of expression of EGF receptor by a mechanism other than inactivation of the receptor kinase and reversed the transformed phenotype of A431 cells to a normal one in the proliferative response to EGF.

  • Labeling of v-Src and BCR-ABL tyrosine kinases with [14C]Herbimycin A and its use in the elucidation of the kinase inactivation mechanism
    FEBS Letters, 1994
    Co-Authors: Hidesuke Fukazawa, Yuko Murakami, Masa Hamada, Yoshimasa Uehara, Satoshi Mizuno, Tomio Takeuchi
    Abstract:

    Abstract The ansamycin antibiotic, Herbimycin A, selectively inactivates cytoplasmic tyrosine kinases, most likely by binding irreversibly to the reactive SH group(s) of kinases. To further investigate the mechanism of Herbimycin A action, we attempted to label tyrosine kinases with [14C]Herbimycin A. p60v-src and p2 10BCR-ABL in immune complexes were labeled with [14C]Herbimycin A, demonstrating that the antibiotic binds directly to tyrosine kinases. Digestion of [14C]Herbimycin A-labeled p60v-src with Staphylococcus taureus V8 protease revealed that the Herbimycin A binding site is within the C-terminal 26-kDa fragment of p60v-src, which contains the tyrosine kinase domain. Herbimycin A treatment inhibited labeling of p60v-src by [14]C]fluorosulfonylbenzoyl adenosine, an affinity labeling reagent of nucleotide binding sites, indicating that Herbimycin A-modified p60v-src cannot interact with ATP. The results suggest that Herbimycin A inactivates tyrosine kinases by binding directly to the kinase domain, thereby inhibiting access to ATP.

  • specific inhibition of cytoplasmic protein tyrosine kinases by Herbimycin a in vitro
    Biochemical Pharmacology, 1991
    Co-Authors: Hidesuke Fukazawa, Yuko Murakami, Satoshi Mizuno, C Yamamoto, Yoshimasa Uehara
    Abstract:

    Abstract Herbimycin A is an antibiotic which reverses transformation caused by various src related oncogenes. The reversion of transformation is restricted to cells transformed by tyrosine kinase coding oncogenes, and accompanies a decrease in kinase activity of the oncogene products. We have shown in vitro that Herbimycin A directly inactivates p60 v-src kinase by conjugating with SH group(s) of the kinase, raising the possibility that the molecular target of the antibiotic for reversion of v- src transformation is the p60 v-src itself. To investigate the relevance of its in vitro tyrosine kinase inactivating activity to in vivo transformation reversing activity, we examined the specificity of Herbimycin A for inhibition of cAMP-dependent kinase, protein kinase C and p210 bcr-abl tyrosine kinase in vitro . Herbimycin A had no inhibitory effect on the activities of cAMP-dependent kinase or protein kinase C, whereas the SH-reagent N -(9-acridinyl)maleimide, which inactivates p60 v-crc in vitro by a mechanism similar to that of Herbimycin A, blocked the two serine/threonine kinases. On the other hand, the activity of p210 bcr-abl tyrosine kinase was inhibited by Herbimycin A treatment. The results indicate that Herbimycin A specifically binds to reactive SH group(s) of cytoplasmic protein tyrosine kinases, and confer the biochemical basis for its selectivity in reversing cell transformation.

Yoshio Honma - One of the best experts on this subject based on the ideXlab platform.

  • 19 allylaminoHerbimycin a an analog of Herbimycin a that is stable against treatment with thiol compounds or granulocyte macrophage colony stimulating factor in human leukemia cells
    Biochimica et Biophysica Acta, 1995
    Co-Authors: Makoto Makishima, Yuri Yamamotoyamaguchi, Yoshio Honma
    Abstract:

    Herbimycin A, a benzoquinonoid ansamycin antibiotic, reduces intracellular phosphorylation by some protein tyrosine kinases and inhibits the proliferation of malignant cells which express high tyrosine kinase activity. Herbimycin A inhibited the proliferation of human monoblastic leukemia U937 cells, but this inhibition was abrogated by the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF). On the other hand, a derivative of Herbimycin A, 19-allylaminoHerbimycin A, inhibited the proliferation of such cells without interference by the addition of GM-CSF. Phosphorylation of MAP kinase and c-myc expression induced by GM-CSF in U937 cells were inhibited by both Herbimycin A and 19-allylaminoHerbimycin A. The time courses of growth inhibition showed that the growth-inhibitory activity of Herbimycin A in U937 cells was initially potent, but gradually decreased in the presence of GM-CSF. Thiol compounds, glutathione (GSH) and 2-mercaptoethanol, abrogated the inhibition of the growth of U937 cells by Herbimycin A, but not by 19-allylaminoHerbimycin A, like GM-CSF. Intracellular GSH content in U937 cells was increased by treatment with GM-CSF, and decreased with Herbimycin A, but returned to the control level with the addition of GM-CSF to Herbimycin A. In thin-layer chromatography, after in vitro incubation with Herbimycin A and GSH, nothing could be detected at the position of intact Herbimycin A, while 19-allylaminoHerbimycin A was stably detected. These findings suggest that changes in the intracellular concentration of GSH play a role in the abrogation of the inhibition of U937 cell growth by Herbimycin A. In the presence of GSH, 19-allylaminoHerbimycin A inhibited the proliferation of U937 cells and Philadelphia chromosome-positive K562 cells more effectively than Herbimycin A. Since GSH plays a role in detoxicating several anticancer drugs, 19-allylaminoHerbimycin A may have therapeutic advantages over Herbimycin A against some types of leukemia.

  • treatment of philadelphia chromosome positive human leukemia in scid mouse model with Herbimycin a bcr abl tyrosine kinase activity inhibitor
    International Journal of Cancer, 1995
    Co-Authors: Yoshio Honma, Yasuhide Hayashi, Yoshinobu Matsuo, Satoshi Omura
    Abstract:

    The molecular basis of the Philadelphia chromosome (Ph 1 ) is a structurally altered c-abl (bcr-abl) gene which encodes an abnormally large protein with protein tyrosine kinase activity. Herbimycin A, which effectively reduced intracellular phosphorylation by bcr-abl tyrosine kinase, preferentially inhibited the growth of Ph 1 -positive leukemia cell lines. Injection of Ph 1 -positive and -negative leukemia cell lines into mice with severe combined immunodeficiency (SCID) resulted in the death of all mice due to leukemia, although the severity of illness varied according to the cell lines used. Administration of Herbimycin A significantly enhanced the survival of mice inoculated with the Ph 1 -positive leukemia cell lines tested but barely affected the survival of mice inoculated with the Ph 1 -negative leukemia cell lines tested. These results suggest that Herbimycin A and related compounds may be useful for the treatment of Ph 1 -positive leukemia. The disease that developed using the Ph 1 -positive leukemia cell line NALM-20 resembled human Ph 1 -positive acute lymphoid leukemia. There was an inverse relationship between the survival time of mice and the number of cells inoculated. The SCID mouse-NALM-20 human leukemia chimera would be a good experimental model for screening tyrosine kinase inhibitors as therapeutic agents against Ph 1 -positive leukemia

  • acycloguanosine and Herbimycin a co operatively inhibit proliferation and induce erythrodifferentiation of human myeloid leukemia k562 cells
    Leukemia Research, 1994
    Co-Authors: Yoshio Honma
    Abstract:

    Acycloguanosine (9-[(2-hydroxyethoxy)methyl]guanosine) induced human erythroleukemia K562 cells to differentiate into hemoglobin-producing cells, and cell growth was highly sensitive to this nucleoside analog. Herbimycin A also induced erythrodifferentiation of the cells, and selectively inhibited proliferation of the cells. Selective inhibition of the proliferation in K562 cells was greatly enhanced by combined treatment with acycloguanosine and Herbimycin A, while the growth of another erythroleukemia cell line without bcr/abl gene (HEL) and normal mouse bone marrow cells was hardly affected by the treatment.

  • effects of Herbimycin a and its derivatives on growth and differentiation of ph1 positive acute lymphoid leukemia cell lines
    Leukemia Research, 1994
    Co-Authors: Seitetsu Sato, Kiyoshi Shibata, Yoshio Honma, Motoo Hozumi, Yasuhide Hayashi, Yoshinobu Matsuo, Satoshi ōmura, Kenichiro Hino, Shigeru Tomoyasu, N Tsuruoka
    Abstract:

    The molecular basis of the Philadelphia chromosome (Ph1) is a structurally altered c-abl (bcr/abl) gene which encodes an abnormally large protein with protein tyrosine kinase activity. Herbimycin A, an inhibitor of tyrosine kinase, preferentially inhibited the growth of Ph1-positive acute lymphoid leukemia (ALL) cell lines, as well as Ph1-positive chronic myeloid leukemia (CML) cell lines. Although noncytotoxic concentrations of Herbimycin A induced erythroid differentiation of two CML-derived cell lines, K562 and KU812, in a previous study, the differentiation-inducing effect of Herbimycin A on Ph1-positive ALL cell lines was less strong. Herbimycin A enhanced some differentiation-associated properties of one Ph1-positive ALL cell line, L2, but the effect of Herbimycin A on the other Ph1-positive ALL cell lines was cytotoxic rather than cytostatic (differentiation-inducing). Several derivatives of Herbimycin A were synthesized and their effects on the cell proliferation of Ph1-positive CML and ALL cell lines were examined. The sensitivities of the Ph1-positive cell lines to Herbimycin A derivatives were different from the data on the rat kidney cell line infected with Rous sarcoma virus (v-src) derived from a previous study, suggesting bcr/abl kinase may differ in sensitivity from other tyrosine kinases. Moreover, the sensitivities of the ALL cell lines were not the same as those of the CML cell lines. These results suggest that a specific inhibitor of bcr/abl kinase could be an effective antileukemic agent against Ph1-positive CML or ALL.

  • Herbimycin a an inhibitor of tyrosine kinase prolongs survival of mice inoculated with myeloid leukemia c1 cells with high expression of v abl tyrosine kinase
    Cancer Research, 1992
    Co-Authors: Yoshio Honma, Motoo Hozumi, Takashi Kasukabe, Junko Okabekado, Hiroaki Kodama, Sachiko Kajigaya, Toshio Suda, Yoshisada Miura
    Abstract:

    Herbimycin A, a benzoquinonoid ansamycin antibiotic, reduces intracellular phosphorylation by some tyrosine kinases, including v-abl. The mouse megakaryoblastic cell line C1 expresses v-abl protein at high levels. Herbimycin A at about 20 ng/ml caused 50% inhibition of growth of C1 cells but at 100 ng/ml scarcely affected the growth of another mouse leukemia cell line, M1 cells, or of normal bone marrow cells. Injection of 10(6) C1 cells into nude mice resulted in death of all the mice within 30 days. Administration of Herbimycin A significantly enhanced the survival of mice inoculated with C1 cells but scarcely affected the survival of mice inoculated with M1 cells. These results suggest that Herbimycin A and/or related compounds may be useful for treatment of some types of leukemia in which tyrosine kinase activity is implicated as a determinant of the oncogenic state.

Satoshi Mizuno - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Herbimycin A on Tyrosine Kinase Receptors and Platelet Derived Growth Factor (PDGF)-Induced Signal Transduction
    Biological & pharmaceutical bulletin, 1998
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    Herbimycin A is widely used as an inhibitor of Src family protein tyrosine kinases but is also reported to induce the downregulation of epidermal growth factor (EGF) receptor number in A431 cells without inhibiting its tyrosine kinase activity. To determine the specificity of the receptor downregulation, we examined its effect on a variety of cell lines which express different levels of EGF receptor and on other tyrosine kinase receptors. Long-term Herbimycin A treatment decreased the amounts of all the tyrosine kinase receptors examined in a dose-dependent manner. It also reduced ligand-stimulated receptor autophosphorylation in accordance with the reduction in the receptor level. Herbimycin A inhibited platelet derived growth factor (PDGF)-induced tyrosine phosphorylation of cellular proteins and DNA synthesis in NIH3T3 cells but did not affect the serum-stimulated DNA synthesis. PDGF-induced tyrosine phosphorylation and activation of c-Src was inhibited but the protein level of c-Src was not reduced by Herbimycin A. The reduced level of c-Src kinase activity correlated with the levels of both PDGF receptor and DNA synthesis. These results indicate that the Herbimycin A treatment selectively downregulates receptor tyrosine kinases, independent of the number of receptors, and suggest that c-Src is to some degree involved in the selective inhibition of PDGF-induced mitogenesis by Herbimycin A.

  • conversion of epidermal growth factor egf into a stimulatory ligand for a431 cell growth by Herbimycin a by decreasing the level of expression of egf receptor
    Biochemical Journal, 1994
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Satoshi Mizuno, Yoshimasa Uehara
    Abstract:

    We examined effect of the tyrosine kinase inhibitor Herbimycin A on A431 human epidermoid carcinoma cells which over-express epidermal growth factor (EGF) receptor. Herbimycin A inhibited the autophosphorylation of EGF-stimulated receptors in intact cells both time- and dose-dependently. The inhibition was found to be due to a decrease in the level of expression of the receptor amount, because Herbimycin A equally decreased the receptor quantity and EGF-stimulated receptor kinase activity in intact cells, but did not exhibit a direct inhibitory effect on EGF receptor kinase activity in vitro. The decrease of the level of EGF receptor was also confirmed by 125I-EGF binding to Herbimycin A-treated cells, and Scatchard analysis showed that the decrease in the receptor number occurred in the major population of the low-affinity binding ones, whereas the number with high-affinity binding was unaffected. Interestingly, although the proliferation of A431 cells was inhibited by EGF, Herbimycin A converted EGF into a stimulatory ligand for cell growth, as determined by both cell number and DNA synthesis. These findings indicated that Herbimycin A decreased the level of expression of EGF receptor by a mechanism other than inactivation of the receptor kinase and reversed the transformed phenotype of A431 cells to a normal one in the proliferative response to EGF.

  • Labeling of v-Src and BCR-ABL tyrosine kinases with [14C]Herbimycin A and its use in the elucidation of the kinase inactivation mechanism
    FEBS Letters, 1994
    Co-Authors: Hidesuke Fukazawa, Yuko Murakami, Masa Hamada, Yoshimasa Uehara, Satoshi Mizuno, Tomio Takeuchi
    Abstract:

    Abstract The ansamycin antibiotic, Herbimycin A, selectively inactivates cytoplasmic tyrosine kinases, most likely by binding irreversibly to the reactive SH group(s) of kinases. To further investigate the mechanism of Herbimycin A action, we attempted to label tyrosine kinases with [14C]Herbimycin A. p60v-src and p2 10BCR-ABL in immune complexes were labeled with [14C]Herbimycin A, demonstrating that the antibiotic binds directly to tyrosine kinases. Digestion of [14C]Herbimycin A-labeled p60v-src with Staphylococcus taureus V8 protease revealed that the Herbimycin A binding site is within the C-terminal 26-kDa fragment of p60v-src, which contains the tyrosine kinase domain. Herbimycin A treatment inhibited labeling of p60v-src by [14]C]fluorosulfonylbenzoyl adenosine, an affinity labeling reagent of nucleotide binding sites, indicating that Herbimycin A-modified p60v-src cannot interact with ATP. The results suggest that Herbimycin A inactivates tyrosine kinases by binding directly to the kinase domain, thereby inhibiting access to ATP.

  • specific inhibition of cytoplasmic protein tyrosine kinases by Herbimycin a in vitro
    Biochemical Pharmacology, 1991
    Co-Authors: Hidesuke Fukazawa, Yuko Murakami, Satoshi Mizuno, C Yamamoto, Yoshimasa Uehara
    Abstract:

    Abstract Herbimycin A is an antibiotic which reverses transformation caused by various src related oncogenes. The reversion of transformation is restricted to cells transformed by tyrosine kinase coding oncogenes, and accompanies a decrease in kinase activity of the oncogene products. We have shown in vitro that Herbimycin A directly inactivates p60 v-src kinase by conjugating with SH group(s) of the kinase, raising the possibility that the molecular target of the antibiotic for reversion of v- src transformation is the p60 v-src itself. To investigate the relevance of its in vitro tyrosine kinase inactivating activity to in vivo transformation reversing activity, we examined the specificity of Herbimycin A for inhibition of cAMP-dependent kinase, protein kinase C and p210 bcr-abl tyrosine kinase in vitro . Herbimycin A had no inhibitory effect on the activities of cAMP-dependent kinase or protein kinase C, whereas the SH-reagent N -(9-acridinyl)maleimide, which inactivates p60 v-crc in vitro by a mechanism similar to that of Herbimycin A, blocked the two serine/threonine kinases. On the other hand, the activity of p210 bcr-abl tyrosine kinase was inhibited by Herbimycin A treatment. The results indicate that Herbimycin A specifically binds to reactive SH group(s) of cytoplasmic protein tyrosine kinases, and confer the biochemical basis for its selectivity in reversing cell transformation.

  • induction of hsp 72 73 by Herbimycin a an inhibitor of transformation by tyrosine kinase oncogenes
    Experimental Cell Research, 1991
    Co-Authors: Yuko Murakami, Hidesuke Fukazawa, Yoshimasa Uehara, Chii Yamamoto, Satoshi Mizuno
    Abstract:

    Herbimycin A, which has been known to inactivate and degrade p60v-src tyrosine kinase, induced an elevated synthesis of a protein with a molecular size of 70 kDa in A431 human epidermoid carcinoma cells. This protein showed the same migration distance on SDS-polyacrylamide gel electrophoresis as that of the protein induced in the cells by heat shock treatment, and this 70-kDa protein was identified as a member of the heat shock protein 70 family (hsp70) through immunoprecipitation with anti-hsp72/73 antibody and partial digestion with V8 protease. The induced level of the 70-kDa protein was dependent on the length of period and the concentration of Herbimycin A treatment. Cellular fractionation and indirect immunofluorescence analyses revealed that the 70-kDa protein induced by Herbimycin A was localized in the cytoplasm, in contrast to the nuclear distribution of hsp70 induced by heat treatment. Induction of hsp70 by Herbimycin A was also observed in several other cells, including HeLa S3 cells, chicken embryo fibroblasts, NIH3T3 cells, and Rous sarcoma virus-transformed NIH3T3 cells.