• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.9-13
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• 2001

Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase II activities. Genistein has been shown to have anticancer proliferation, differentiation and chemopreventive effects. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of p53-null human prostate carcinoma cells.(omitted)

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.1077-1079
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• 2011

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.4
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• pp.56-73
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• 2007

Purpose: 이 실험은 골다공증의 치료약물로 자하거의 골질재흡수 억제효과를 검토하기 위하여 설계되었다. Methods: 자하거의 골질재흡수 효과를 확인하기 위하여 생쥐의 두개골 골모세포를 이용하여 Cyclooxygenase-1(COX-1), COX-2, $TGF-{\beta}$, $L-1{\beta}$, $TNF-{\alpha}$, IL-6, prostaglandin E2등의 활성화 정도를 측정하였으며, 골조직의 미세구조적 변화를 확인하였다. Results: 자하거는 $IL-1{\beta}$, $TNF-{\alpha}$, IL-6 또는 그 세가지의 조합에 의하여 유발된 PGE2의 생성 뿐만 아니라 COX-2 mRNA 수치도 감소시켰으나 COX-1 mRNA 수치에는 영향을 주지 않았다. 이로써 자하거는 시험관내에서 그리고 생체내에서 펩티드의 인산화를 억제함으로써 골의 재흡수를 저해하였다. 그리고 자하거는 생쥐에서 $IL-1{\beta}$에 의해 유발된 고칼슘혈증을 감소시켰고, 골의 재흡수를 저해하는 경로를 통하여 골에 대한 보호효과를 보여줌으로써 조기에 난소 절제한 쥐에서 골질감소와 미세구조적 변화를 부분적으로 방지하였다. 이러한 결과는 PGE2 생성에 대한 $IL-1{\beta}$, $TNF-{\alpha}$, IL-6사이의 상승효과는 COX-2의 유전자 발현이 증가한 결과이며 이러한 tyrosine kinase가 생쥐의 두개골 골모세포에서 COX-2의 신호전달에 관계한다는 것을 보여준다. Conclusion: 자하거가 생쥐의 두개골 골모세포에서 여러 신호전달물질의 활성화를 통하여 골질재흡수를 저해하는 특성을 확인함으로써 앞으로 골다공증의 예방과 치료에 대한 추가적인 임상연구가 필요할 것으로 사료된다.

• Biomedical Science Letters
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• v.13 no.2
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• pp.119-125
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• 2007

It is widely known that protein tyrosine kinases (PTKs) are involved in controlling many biological processes such as cell growth, differentiation, proliferation, survival and apoptosis. An $\alpha3\beta4$ subunit combination acts as a major functional acetylcholine receptor (nAChRs) in male rat major pelvic ganglion (MPG) neurons, and their activation induces fast inward currents and intracellular calcium increases. Recently it has been reported that the activity of acetylcholine receptors (AChRs) in some neurons can be negatively regulated by PTKs. However, the exact mechanism of regulation of nAChRs by PTKs is poorly understood. Therefore, we examined the potential role particular in nAChR by PTK using electrophysiology and calcium imaging in male rat MPG neurons. ACh induced inward currents and $(Ca^{2+})_i$ increases in MPG neurons, concomitantly. These responses were inhibited by more than 90% in $Na^+$- or $Ca^{2+}$- free solution. $\alpha$-conotoxin AuIB, a selective $\alpha3\beta4$ nAChR blocket, inhibited ACh-induced inward currents. Genistein (10 $\mu$M), a broad-spectrum tyrosine kinase inhibitor, markedly decreased ACh-induced currents and $Ca^{2+}$ transients, whereas 10 $\mu$M genistin, an inactive analogue, had little effect. Overall these data suggest that the activities of $\alpha3\beta4$ AChRs in MPG neurons are positively regulated by PTK. In conclusion, trosine kinase may be one of the key factors in the regulation of $\alpha3\beta4$ nAChRs in rat MPG neurons, which may play an important roles in the autonomic neuronal function such as synaptic transmission, autonomic reflex, and neuronal plasticity.

• Biomolecules & Therapeutics
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• v.29 no.1
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• pp.41-51
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• 2021

Src family kinases (SFKs), an important group of non-receptor tyrosine kinases, are suggested to be excessively activated during various types of tissue fibrosis. The present study investigated the effect of KF-1607, an orally active and a newly synthesized Src kinase inhibitor (SKI) with proposed low toxicity, in preventing the progression of renal interstitial fibrosis. Unilateral ureteral obstruction (UUO) surgery was performed in 6-week-old male C57BL/6 mice to induce renal interstitial fibrosis. Either KF-1607 (30 mg/kg, oral gavage) or PP2 (2 mg/kg, intraperitoneal injection), a common experimental SKI, was administered to mice for seven days, started one day prior to surgery. UUO injury-induced SFK expression, including Src, Fyn, and Lyn kinase. SFK inhibition by KF-1607 prevented the progression of tubular injury in UUO mice, as indicated by decreases in albuminuria, urinary KIM-1 excretion, and kidney NGAL protein expression. Renal tubulointerstitial fibrosis was attenuated in response to KF-1607, as shown by decreases in α-SMA, collagen I and IV protein expression, along with reduced Masson's trichrome and collagen-I staining in kidneys. KF-1607 also inhibited inflammation in the UUO kidney, as exhibited by reductions in F4/80 positive-staining and protein expression of p-NFκB and ICAM. Importantly, the observed effects of KF-1607 were similar to those of PP2. A new pan Src kinase inhibitor, KF-1607, is a potential pharmaceutical agent to prevent the progression of renal interstitial fibrosis.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.200-206
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• 2007

Pharmacophore models for lymphocyte-specific protein tyrosine kinase (P56 LCK) were developed using CATALYST HypoGen with a training set comprising of 25 different P56 LCK inhibitors. The best quantitative pharmacophore hypothesis comprises of one hydrogen bond acceptor, one hydrogen bond donor, one hydrophobic aliphatic and one ring aromatic features with correlation coefficient of 0.941, root mean square deviation (RMSD) of 0.933 and cost difference (null cost-total cost) of 66.23. The pharmacophore model was validated by two methods and the validated model was further used to search databases for new compounds with good estimated LCK inhibitory activity. These compounds were evaluated for their binding properties at the active site by molecular docking studies using GOLD software. The compounds with good estimated activity and docking scores were evaluated for physiological properties based on Lipinski's rules. Finally 68 compounds satisfied all the properties required to be a successful inhibitor candidate.

• Journal of Veterinary Clinics
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• v.34 no.1
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• pp.43-46
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• 2017

A 10-year-old, spayed, female Cocker Spaniel was referred to our hospital with a history of a cough and dyspnea. The patient was tentatively diagnosed with a chemodectoma based on clinical features evident on echocardiography and computed tomography. Metronomic chemotherapy utilizing toceranib phosphate as well as medications for congestive heart failure were administered. During the period chemotherapy was administered (nine months from the time of diagnosis), clinical improvement was noted without the development of any adverse effects. However, clinical signs recurred after chemotherapy was discontinued at the owner's request. When the patient was reevaluated via computed tomography, it was found that the size of the mass had increased. The patient developed severe dyspnea secondary to recurrent pleural effusion and was euthanized 65 days after clinical signs reappeared. A necropsy was performed and the patient was definitively diagnosed with a chemodectoma based on histopathologic and immunohistochemical analysis. This case report describes the clinical application of metronomic chemotherapy with toceranib phosphate, which is a tyrosine kinase inhibitor, in the treatment of a chemodectoma. We propose that this treatment may improve the quality of life and result in a prolonged survival time compared to treatment with medications for congestive heart failure alone.

• Molecules and Cells
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• v.20 no.2
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• pp.280-287
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• 2005

The insulin-mediated Ras/mitogen-activated protein (MAP) kinase cascade was examined in SK-N-BE(2) and PC12 cells, which can and cannot produce reactive oxygen species (ROS), respectively. Tyrosine phosphorylation of the insulin receptor and insulin receptor substrate 1 (IRS-1) was much lower in SK-N-BE(2) cells than in PC12 cells when the cells were treated with insulin. The insulin-mediated interaction of IRS-1 with Grb2 was observed in PC12 but not in SK-N-BE(2) cells. Moreover, the activity of extracellular-signal-related kinase (ERK) was much lower in SK-N-BE(2) than in PC12 cells when the cells were treated with insulin. Application of exogenous $H_2O_2$ caused increased tyrosine phosphorylation and Grb2 binding to IRS-1 in SK-N-BE(2) cells, while exposure to an $H_2O_2$ scavenger (N-acetylcysteine) or to a phophatidylinositol-3 kinase inhibitor (wortmannin), and expression of a dominant negative Rac1, decreased the activation of ERK in insulin-stimulated PC12 cells. These results indicate that the transient increase of ROS is needed to activate ERK in insulin-mediated signaling and that an inability to generate ROS is the reason for the insulin insensitivity of SK-N-BE(2) cells.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.144-149
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• 2005

Background: Fc receptor-mediated phagocytosis is a complex process involving the activation of kinases and phosphatases. FcgammaRIIB has been known to transduces inhibitory signals through an immunoreceptor tyrosine-based inhibitory motif (ITIM) in cytoplasmic domains. In this study, we examined the involvement of inositol-phosphatase in the Fc receptor-mediated phagocytosis. Methods: J774 cells were infected using vaccinia viral vector containing SH2 domain-containing inositol-phosphatase (SHIP) cDNA and stimulated with the sensitized sheep red blood cells. Results: Stimulation of J774 cells induced the tyrosine phosphorylation of SHIP which was maximal at 5 minutes. Phosphatidylinositol-3 (PI-3) kinase inhibitor (wortmannin) inhibits J774 cell phagocytosis of sensitized sheep red blood cells in a dose-dependent manner. Heterologious expression of SHIP in J774 cells inhibits phagocytosis of sensitized sheep red blood cells in a dose-dependency manner, but catalytically dead mutants of SHIP has no effect on phagocytosis. Conclusion: These results strongly suggest that the active signals mediated by PI-3 kinase are opposed by inhibitory signals through SHIP in the regulation of Fc receptor-mediated phagocytosis.

• Applied Microscopy
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• v.47 no.4
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• pp.233-237
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• 2017

Chronic eosinophilic leukemia (CEL) is a myeloproliferative disease with an increased number of mature eosinophils and their precursors, which results in infiltration into organs and organ enlargement. The main cause of this disease is the overexpression of tyrosine kinase. However, there is a need for alternative medication, because some patients are resistant to imatinib, which is a tyrosine kinase inhibitor for leukemia. Many studies have indicated that S100A8 and splicing factor proline and glutamine-rich (SFPQ) function as initiation signals of apoptosis in CEL cells. We reviewed structural studies on CEL cells related to S100A8 and SFPQ. Particularly, this review highlighted microscopic results for the study of S100A8 and SFPQ in CEL cells.