scholarly journals The role of tyrosine kinase in gonadotropin-induced ovulation in the rat ovary

1998 ◽  
pp. 594-600 ◽  
Author(s):  
T Shimamoto ◽  
M Yamoto ◽  
R Nakano
Keyword(s):  
Tyrosine Kinase ◽  
Granulosa Cells ◽  
Kinase Inhibitor ◽  
Tissue Type ◽  
Corpora Lutea ◽  
Induced Ovulation ◽  
Rat Ovary ◽  
Ovulatory Process

OBJECTIVES: Our purpose was to elucidate the involvement of the tyrosine kinase pathway in gonadotropin-induced ovulation in the rat ovary. STUDY DESIGN: We investigated the effect of a tyrosine kinase inhibitor, tyrphostin, on the rat ovulatory process in vivo and in vitro. METHODS: In cultured rat granulosa cells, the effect of tyrphostin on LH-, dibutyryl cyclic AMP ((Bu)2cAMP)- or forskolin-stimulated tissue type plasminogen activator (tPA) activities was examined by using a fibrin autography technique. In an in vivo system, tyrphostin was injected into the bursal cavity of the ovary in pregnant mare serum gonadotropin-treated rats, just before human chorionic gonadotropin administration. After 24 h, the number of oocytes in the oviduct was counted and the tyrphostin-treated ovaries were examined histologically. RESULTS: Tyrphostin inhibited LH-stimulated tPA activity but did not affect (Bu)2cAMP- or forskolin-stimulated ones. In an in vivo study, tyrphostin suppressed oocyte release dose-dependently. Histological observations revealed that tyrphostin-treated ovaries contained many large unruptured follicles and a few corpora lutea. CONCLUSION: This study suggests that the suppressive effect of tyrphostin on ovulation may be partly due to tPA activity inhibition in the granulosa cells via the suppression of tyrosine kinase activity. Additionally, tyrosine kinase phosphorylation may be involved in gonadotropin-activated signaling systems in the rat ovulatory process.

scholarly journals Targeting USP47 overcomes tyrosine kinase inhibitor resistance and eradicates leukemia stem/progenitor cells in chronic myelogenous leukemia

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hu Lei ◽  
Han-Zhang Xu ◽  
Hui-Zhuang Shan ◽  
Meng Liu ◽  
Ying Lu ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Progenitor Cells ◽  
Chronic Myelogenous Leukemia ◽  
Drug Targets ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Myelogenous Leukemia ◽  
Tki Resistance

AbstractIdentifying novel drug targets to overcome resistance to tyrosine kinase inhibitors (TKIs) and eradicating leukemia stem/progenitor cells are required for the treatment of chronic myelogenous leukemia (CML). Here, we show that ubiquitin-specific peptidase 47 (USP47) is a potential target to overcome TKI resistance. Functional analysis shows that USP47 knockdown represses proliferation of CML cells sensitive or resistant to imatinib in vitro and in vivo. The knockout of Usp47 significantly inhibits BCR-ABL and BCR-ABLT315I-induced CML in mice with the reduction of Lin−Sca1+c-Kit+ CML stem/progenitor cells. Mechanistic studies show that stabilizing Y-box binding protein 1 contributes to USP47-mediated DNA damage repair in CML cells. Inhibiting USP47 by P22077 exerts cytotoxicity to CML cells with or without TKI resistance in vitro and in vivo. Moreover, P22077 eliminates leukemia stem/progenitor cells in CML mice. Together, targeting USP47 is a promising strategy to overcome TKI resistance and eradicate leukemia stem/progenitor cells in CML.

scholarly journals Integrin α6 mediates the drug resistance of acute lymphoblastic B-cell leukemia

Blood ◽  
2020 ◽  
Vol 136 (2) ◽  
pp. 210-223 ◽  
Author(s):  
Eun Ji Gang ◽  
Hye Na Kim ◽  
Yao-Te Hsieh ◽  
Yongsheng Ruan ◽  
Heather A. Ogana ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Tyrosine Kinase ◽  
B Cell ◽  
Kinase Inhibitor ◽  
Residual Disease ◽  
Lymphoblastic Leukemia ◽  
Underlying Mechanism ◽  
Conditional Knockout

Abstract Resistance to multimodal chemotherapy continues to limit the prognosis of acute lymphoblastic leukemia (ALL). This occurs in part through a process called adhesion-mediated drug resistance, which depends on ALL cell adhesion to the stroma through adhesion molecules, including integrins. Integrin α6 has been implicated in minimal residual disease in ALL and in the migration of ALL cells to the central nervous system. However, it has not been evaluated in the context of chemotherapeutic resistance. Here, we show that the anti-human α6-blocking Ab P5G10 induces apoptosis in primary ALL cells in vitro and sensitizes primary ALL cells to chemotherapy or tyrosine kinase inhibition in vitro and in vivo. We further analyzed the underlying mechanism of α6-associated apoptosis using a conditional knockout model of α6 in murine BCR-ABL1+ B-cell ALL cells and showed that α6-deficient ALL cells underwent apoptosis. In vivo deletion of α6 in combination with tyrosine kinase inhibitor (TKI) treatment was more effective in eradicating ALL than treatment with a TKI (nilotinib) alone. Proteomic analysis revealed that α6 deletion in murine ALL was associated with changes in Src signaling, including the upregulation of phosphorylated Lyn (pTyr507) and Fyn (pTyr530). Thus, our data support α6 as a novel therapeutic target for ALL.

scholarly journals Immunomodulatory Effects of Tyrosine Kinase Inhibitor In Vitro and In Vivo Study

2018 ◽  
Vol 24 (2) ◽  
pp. 267-275 ◽  
Author(s):  
Elena Marinelli Busilacchi ◽  
Andrea Costantini ◽  
Nadia Viola ◽  
Benedetta Costantini ◽  
Jacopo Olivieri ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Tyrosine Kinase Inhibitor ◽  
Kinase Inhibitor ◽  
In Vivo Study ◽  
Immunomodulatory Effects

scholarly journals Dynamic Structural Modeling Revealed That Nilotinib Inhibits Smoothened Signaling

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Kirti Kandhwal Chahal ◽  
Jie Li ◽  
Irina Kufareva ◽  
Donald Durden ◽  
Robert Wechsler Reya ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Computational Modeling ◽  
Kinase Inhibitor ◽  
Acquired Resistance ◽  
Protein Docking ◽  
High Rate ◽  
Protein Levels ◽  
Matching Criteria

Abstract INTRODUCTION Dysregulation of the 7-transmembrane receptors Smoothened (SMO) and other components of the Hedgehog (Hh) signaling pathway causes several cancers, including medulloblastoma (MB) and glioblastoma. However, SMO-specific antagonists produced mixed results in clinical trials, marked by a limited efficacy and a high rate of acquired resistance in tumors. METHODS Computational modeling of protein docking sites, analytical configuration modeling of crystallographic data, and in Vitro and in Vivo xenograft experiments. RESULTS Using computational modeling of SMO structure, we discovered that Nilotinib, an FDA-approved receptor tyrosine kinase inhibitor, directly binds to SMO. Furthermore, Nilotinib was more efficacious than the SMO-specific antagonist Vismodegib in inhibiting cell growth and Gli-1 mRNA and protein levels in Hh-dependent MB cells and glioblastoma cells. It also reduced tumor growth in the Hh-dependent MB and glioblastoma mouse xenograft models. These results indicate that in addition to its ability to inhibit several tyrosine kinase-mediated proliferative pathways, Nilotinib is active against the Hh pathway. CONCLUSION The newly discovered extension of Nilotinib target profile holds promise for the treatment of Hh-dependent cancers. It also calls for comprehensive characterization of pharmacology for other drugs and incorporation of their multitarget profiles into drug-disease matching criteria for personalized medicine.

scholarly journals Inhibition of oocyte growth factors in vivo modulates ovarian folliculogenesis in neonatal and immature mice

Reproduction ◽  
2010 ◽  
Vol 139 (3) ◽  
pp. 587-598 ◽  
Author(s):  
Samu Myllymaa ◽  
Arja Pasternack ◽  
David G Mottershead ◽  
Matti Poutanen ◽  
Minna M Pulkki ◽  
...  
Keyword(s):  
Growth Factors ◽  
Granulosa Cells ◽  
Microscopic Analysis ◽  
Corpora Lutea ◽  
Electron Microscopic ◽  
Oocyte Growth ◽  
Long Term Study ◽  
Ovarian Folliculogenesis

Growth differentiation factor-9 (GDF9) and bone morphogenetic protein-15 (BMP15) are among the key regulators transmitting the signaling between the oocyte and the surrounding granulosa cells. Previously, it has been shown that a recombinant BMP type II receptor ectodomain–Fc fusion protein (BMPR2ecd–Fc) is able to inhibit the actions of GDF9 and BMP15 in vitro. Here, we have produced bioactive BMPR2ecd–Fc, which was injected i.p. into neonatal mice. Early folliculogenesis was first studied by injecting mice five times with various doses of BMPR2ecd–Fc during the postnatal days 4–12. Folliculogenesis was affected dose dependently, as evidenced by a decreased mitogenesis of granulosa cells of the growing follicles. Furthermore, we also noticed a decrease in the number of secondary and tertiary follicles as well as an increase in the oocyte size. Electron microscopic analysis revealed that the ultrastructure of the granulosa cells of the primary follicles was not affected by the BMPR2ecd–Fc treatment. A second study was conducted to investigate whether a longer treatment with 12 injections during postnatal days 4–28 would inhibit folliculogenesis. Similar effects were observed in the two studies on the early follicular developmental stages. However, in the long-term study, later stages of folliculogenesis were not blocked but rather increased numbers of antral follicles, preovulatory follicles, and corpora lutea were found. We conclude that BMPR2ecd–Fc is a potent modulator of ovarian folliculogenesis in vivo, and thus, is a valuable tool for studying the physiology and downstream effects of oocyte-derived growth factors in vivo.

Tyrosine kinase-deficient Wvc-kit induces mast cell adhesion and chemotaxis

1998 ◽  
Vol 275 (5) ◽  
pp. C1291-C1299 ◽  
Author(s):  
Jaroslaw Dastych ◽  
Dennis Taub ◽  
Mary C. Hardison ◽  
Dean D. Metcalfe
Keyword(s):  
Mast Cell ◽  
Cell Adhesion ◽  
Mast Cells ◽  
Tyrosine Kinase ◽  
Kinase Inhibitor ◽  
Mouse Bone Marrow ◽  
Intact Cells ◽  
Protein Kinase C Inhibitors

W/Wvmice are deficient in tissue mast cells, and mast cells cultured from these mice do not proliferate in response to the c-kit ligand, stem cell factor (SCF). In this paper, we report that mouse bone marrow cultured mast cells derived from W/Wvmice do adhere to fibronectin in the presence of SCF and exhibit chemotaxis to SCF, and we explore this model for the understanding of c-kit-mediated signaling pathways. Both in vitro and in vivo (in intact cells) phosphorylation experiments demonstrated a low residual level of W/Wvc-kit protein phosphorylation. SCF-induced responses in W/Wvmast cells were abolished by the tyrosine kinase inhibitor herbimycin A and by the phospatidylinositol 3-kinase (PI 3-kinase) inhibitor wortmannin but were not affected by protein kinase C inhibitors. These observations are consistent with the conclusions that Wvc-kit initiates a signaling process that is PI 3-kinase dependent and that mutated Wvc-kit retains the ability to initiate mast cell adhesion and migration.

TEL/PDGFβR Induces Hematologic Malignancies in Mice That Respond to a Specific Tyrosine Kinase Inhibitor

Blood ◽  
1999 ◽  
Vol 93 (5) ◽  
pp. 1707-1714 ◽  
Author(s):  
Michael H. Tomasson ◽  
Ifor R. Williams ◽  
Robert Hasserjian ◽  
Chirayu Udomsakdi ◽  
Shannon M. McGrath ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Tyrosine Kinase Inhibitor ◽  
Tyrosine Kinases ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Transgenic Animals ◽  
Myeloid Lineage ◽  
Protein Tyrosine

Abstract The TEL/PDGFβR fusion protein is expressed as the consequence of a recurring t(5;12) translocation associated with chronic myelomonocytic leukemia (CMML). Unlike other activated protein tyrosine kinases associated with hematopoietic malignancies, TEL/PDGFβR is invariably associated with a myeloid leukemia phenotype in humans. To test the transforming properties of TEL/PDGFβR in vivo, and to analyze the basis for myeloid lineage specificity in humans, we constructed transgenic mice with TEL/PDGFβR expression driven by a lymphoid-specific immunoglobulin enhancer-promoter cassette. These mice developed lymphoblastic lymphomas of both T and B lineage, demonstrating that TEL/PDGFβR is a transforming protein in vivo, and that the transforming ability of this fusion is not inherently restricted to the myeloid lineage. Treatment of TEL/PDGFβR transgenic animals with a protein tyrosine kinase inhibitor with in vitro activity against PDGFβR (CGP57148) resulted in suppression of disease and a prolongation of survival. A therapeutic benefit was apparent both in animals treated before the development of overt clonal disease and in animals transplanted with clonal tumor cells. These results suggest that small-molecule tyrosine kinase inhibitors may be effective treatment for activated tyrosine kinase–mediated malignancies both early in the course of disease and after the development of additional transforming mutations.

Sign in / Sign up

Export Citation Format

Share Document