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1.
China Tropical Medicine ; (12): 49-2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-976379

RESUMO

@#Abstract: Objective To analyze the application effect of rapid diagnostic techniques in Shaanxi from 2016 to 2020,and to provide basis for further optimizing the process of tuberculosis detection and formulating prevention and control strategies. Methods A total of 104 437 cases of tuberculosis patients registered in Shaanxi Province from 2016-2020 were exported from the Tuberculosis Information Management System (The subsystem of China Disease Prevention and Control Information System) according to first management unit, and the laboratory test results of sputum smear, sputum culture and molecular tests were collected to statistically analyzed the positive rate of etiology, sputum smear, sputum culture, molecular biology testing rate, and indicators of positive testing rate of tuberculosis patients. Results From 2016 to 2020, the etiology�positive rate of tuberculosis in Shaanxi province were 13.49% (2 664/19 754), 22.68% (5 081/22 401), 35.99% (8 232/22 876), 48.14% (10 438 / 21 682), 52.65% (9 332 / 17 724), respectively, with an increasing trend (χ2 trend=9 473.12, P<0.001) year by year; the proportion of molecular tests positive only in etiology-positive pulmonary tuberculosis (PTB) were 0 (0/2 664), 0.16% (8/5 081), 15.44% (1 271/8 232), 27.58% (2 879/10 438), 31.52% (2 941/9 332), respectively, with an increasing trend year by year (χ2 trend=2 971.44, P<0.001); the molecular test rates of the 5 years were 0.01% (2 / 19 754), 0.38%(85 / 22 401), 21.11% (4 828/22 876), 52.42%(11 365/21 682), 55.18%(9 780/17 724), respectively, with an increasing trend year by year (χ2 trend = 28 269.23, P<0.001). The rate of molecular test in sputum smear-negative was 22.72%(17 976 / 79 130). The proportion of patients with only molecular test-positive was 33.43% (4 032/12 062) in municipal designated hospitals, and 11.99%(2 279/ 19 014) in county-level designated hospitals, the difference was statistically significant (χ2 =2 096.46, P<0.001). Conclusions The rate of molecular biology testing in Shaanxi Province from 2016 to 2020 showed a year-on-year increase. Through the application of rapid molecular tests, the etiology-positive rates of tuberculosis have been increased significantly,but the current molecular test detection rate is not high compared with other provinces, especially in county-level designated hospitals and smear-negative patients, so we should make a big promotion in application of rapid molecular technique.

2.
Mol Cancer Ther ; 21(1): 3-15, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34737197

RESUMO

Protein arginine methyltransferase 5 (PRMT5) overexpression in hematologic and solid tumors methylates arginine residues on cellular proteins involved in important cancer functions including cell-cycle regulation, mRNA splicing, cell differentiation, cell signaling, and apoptosis. PRMT5 methyltransferase function has been linked with high rates of tumor cell proliferation and decreased overall survival, and PRMT5 inhibitors are currently being explored as an approach for targeting cancer-specific dependencies due to PRMT5 catalytic function. Here, we describe the discovery of potent and selective S-adenosylmethionine (SAM) competitive PRMT5 inhibitors, with in vitro and in vivo characterization of clinical candidate PF-06939999. Acquired resistance mechanisms were explored through the development of drug resistant cell lines. Our data highlight compound-specific resistance mutations in the PRMT5 enzyme that demonstrate structural constraints in the cofactor binding site that prevent emergence of complete resistance to SAM site inhibitors. PRMT5 inhibition by PF-06939999 treatment reduced proliferation of non-small cell lung cancer (NSCLC) cells, with dose-dependent decreases in symmetric dimethyl arginine (SDMA) levels and changes in alternative splicing of numerous pre-mRNAs. Drug sensitivity to PF-06939999 in NSCLC cells associates with cancer pathways including MYC, cell cycle and spliceosome, and with mutations in splicing factors such as RBM10. Translation of efficacy in mouse tumor xenograft models with splicing mutations provides rationale for therapeutic use of PF-06939999 in the treatment of splicing dysregulated NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , S-Adenosilmetionina/metabolismo , Animais , Apoptose , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Resistência a Medicamentos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Camundongos
3.
ACS Med Chem Lett ; 11(6): 1175-1184, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32550998

RESUMO

Two novel compounds were identified as Naa50 binders/inhibitors using DNA-encoded technology screening. Biophysical and biochemical data as well as cocrystal structures were obtained for both compounds (3a and 4a) to understand their mechanism of action. These data were also used to rationalize the binding affinity differences observed between the two compounds and a MLGP peptide-containing substrate. Cellular target engagement experiments further confirm the Naa50 binding of 4a and demonstrate its selectivity toward related enzymes (Naa10 and Naa60). Additional analogs of inhibitor 4a were also evaluated to study the binding mode observed in the cocrystal structures.

4.
Adv Mater ; 31(42): e1903599, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31486161

RESUMO

Fluorescence imaging is an indispensable tool in biology, with applications ranging from single-cell to whole-animal studies and with live mapping of neuronal activity currently receiving particular attention. To enable fluorescence imaging at cellular scale in freely moving animals, miniaturized microscopes and lensless imagers are developed that can be implanted in a minimally invasive fashion; but the rigidity, size, and potential toxicity of the involved light sources remain a challenge. Here, narrowband organic light-emitting diodes (OLEDs) are developed and used for fluorescence imaging of live cells and for mapping of neuronal activity in Drosophila melanogaster via genetically encoded Ca2+ indicators. In order to avoid spectral overlap with fluorescence from the sample, distributed Bragg reflectors are integrated onto the OLEDs to block their long-wavelength emission tail, which enables an image contrast comparable to conventional, much bulkier mercury light sources. As OLEDs can be fabricated on mechanically flexible substrates and structured into arrays of cell-sized pixels, this work opens a new pathway for the development of implantable light sources that enable functional imaging and sensing in freely moving animals.


Assuntos
Cálcio/metabolismo , Microscopia de Fluorescência/instrumentação , Semicondutores , Animais , Drosophila melanogaster/citologia , Camundongos , Células NIH 3T3 , Neurônios/metabolismo
5.
J Med Chem ; 61(3): 650-665, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29211475

RESUMO

A new series of lactam-derived EZH2 inhibitors was designed via ligand-based and physicochemical-property-based strategies to address metabolic stability and thermodynamic solubility issues associated with previous lead compound 1. The new inhibitors incorporated an sp3 hybridized carbon atom at the 7-position of the lactam moiety present in lead compound 1 as a replacement for a dimethylisoxazole group. This transformation enabled optimization of the physicochemical properties and potency compared to compound 1. Analysis of relationships between calculated log D (clogD) values and in vitro metabolic stability and permeability parameters identified a clogD range that afforded an increased probability of achieving favorable ADME data in a single molecule. Compound 23a exhibited the best overlap of potency and pharmaceutical properties as well as robust tumor growth inhibition in vivo and was therefore advanced as a development candidate (PF-06821497). A crystal structure of 23a in complex with the three-protein PRC2 complex enabled understanding of the key structural features required for optimal binding.


Assuntos
Desenho de Fármacos , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Isoquinolinas/farmacologia , Isoquinolinas/farmacocinética , Administração Oral , Disponibilidade Biológica , Linhagem Celular Tumoral , Humanos , Isoquinolinas/administração & dosagem , Isoquinolinas/química , Modelos Moleculares , Conformação Molecular
6.
Adv Mater ; 28(35): 7620-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27337524

RESUMO

Efficient sky-blue organic light-emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) display a three orders of magnitude increase in lifetime, which is superior to those of controlled phosphorescent OLEDs used in this study. The combination of electro-oxidation and photo-oxidation of the TADF emitters in their triplet excited-states is suppressed through molecule design and device engineering.

7.
Nat Commun ; 7: 11384, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-27122193

RESUMO

Polycomb repressive complex 2 (PRC2) mediates gene silencing through chromatin reorganization by methylation of histone H3 lysine 27 (H3K27). Overexpression of the complex and point mutations in the individual subunits of PRC2 have been shown to contribute to tumorigenesis. Several inhibitors of the PRC2 activity have shown efficacy in EZH2-mutated lymphomas and are currently in clinical development, although the molecular basis of inhibitor recognition remains unknown. Here we report the crystal structures of the inhibitor-bound wild-type and Y641N PRC2. The structures illuminate an important role played by a stretch of 17 residues in the N-terminal region of EZH2, we call the activation loop, in the stimulation of the enzyme activity, inhibitor recognition and the potential development of the mutation-mediated drug resistance. The work presented here provides new avenues for the design and development of next-generation PRC2 inhibitors through establishment of a structure-based drug design platform.


Assuntos
Antineoplásicos/química , Inibidores Enzimáticos/química , Complexo Repressor Polycomb 2/antagonistas & inibidores , Complexo Repressor Polycomb 2/química , Resistencia a Medicamentos Antineoplásicos , Proteína Potenciadora do Homólogo 2 de Zeste/química , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Modelos Moleculares , Mutação , Neoplasias/genética , Neoplasias/metabolismo , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo
8.
N Engl J Med ; 374(1): 54-61, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26698910

RESUMO

In a patient who had metastatic anaplastic lymphoma kinase (ALK)-rearranged lung cancer, resistance to crizotinib developed because of a mutation in the ALK kinase domain. This mutation is predicted to result in a substitution of cysteine by tyrosine at amino acid residue 1156 (C1156Y). Her tumor did not respond to a second-generation ALK inhibitor, but it did respond to lorlatinib (PF-06463922), a third-generation inhibitor. When her tumor relapsed, sequencing of the resistant tumor revealed an ALK L1198F mutation in addition to the C1156Y mutation. The L1198F substitution confers resistance to lorlatinib through steric interference with drug binding. However, L1198F paradoxically enhances binding to crizotinib, negating the effect of C1156Y and resensitizing resistant cancers to crizotinib. The patient received crizotinib again, and her cancer-related symptoms and liver failure resolved. (Funded by Pfizer and others; ClinicalTrials.gov number, NCT01970865.).


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Lactamas Macrocíclicas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/genética , Aminopiridinas , Quinase do Linfoma Anaplásico , Sítios de Ligação , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Crizotinibe , Feminino , Humanos , Lactamas , Falência Hepática/etiologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/genética , Pessoa de Meia-Idade , Estrutura Molecular , Pirimidinas/uso terapêutico , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Sulfonas/uso terapêutico
10.
ACS Appl Mater Interfaces ; 7(22): 11965-71, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-25970499

RESUMO

The electrical doping nature of a strong electron acceptor, 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HATCN), is investigated by doping it in a typical hole-transport material, N,N'-bis(naphthalen-1-yl)-N,N'-diphenylbenzidine (NPB). A better device performance of organic light-emitting diodes (OLEDs) was achieved by doping NPB with HATCN. The improved performance could, in principle, arise from a p-type doping effect in the codeposited thin films. However, physical characteristics evaluations including UV-vis absorption, Fourier transform infrared absorption, and X-ray photoelectron spectroscopy demonstrated that there was no obvious evidence of charge transfer in the NPB:HATCN composite. The performance improvement in NPB:HATCN-based OLEDs is mainly attributed to an interfacial modification effect owing to the diffusion of HATCN small molecules. The interfacial diffusion effect of the HATCN molecules was verified by the in situ ultraviolet photoelectron spectroscopy evaluations.

11.
Proc Natl Acad Sci U S A ; 112(11): 3493-8, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25733882

RESUMO

Oncogenic c-ros oncogene1 (ROS1) fusion kinases have been identified in a variety of human cancers and are attractive targets for cancer therapy. The MET/ALK/ROS1 inhibitor crizotinib (Xalkori, PF-02341066) has demonstrated promising clinical activity in ROS1 fusion-positive non-small cell lung cancer. However, emerging clinical evidence has shown that patients can develop resistance by acquiring secondary point mutations in ROS1 kinase. In this study we characterized the ROS1 activity of PF-06463922, a novel, orally available, CNS-penetrant, ATP-competitive small-molecule inhibitor of ALK/ROS1. In vitro, PF-06463922 exhibited subnanomolar cellular potency against oncogenic ROS1 fusions and inhibited the crizotinib-refractory ROS1(G2032R) mutation and the ROS1(G2026M) gatekeeper mutation. Compared with crizotinib and the second-generation ALK/ROS1 inhibitors ceritinib and alectinib, PF-06463922 showed significantly improved inhibitory activity against ROS1 kinase. A crystal structure of the PF-06463922-ROS1 kinase complex revealed favorable interactions contributing to the high-affinity binding. In vivo, PF-06463922 showed marked antitumor activity in tumor models expressing FIG-ROS1, CD74-ROS1, and the CD74-ROS1(G2032R) mutation. Furthermore, PF-06463922 demonstrated antitumor activity in a genetically engineered mouse model of FIG-ROS1 glioblastoma. Taken together, our results indicate that PF-06463922 has potential for treating ROS1 fusion-positive cancers, including those requiring agents with CNS-penetrating properties, as well as for overcoming crizotinib resistance driven by ROS1 mutation.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Lactamas Macrocíclicas/farmacologia , Mutação/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Pirazóis/farmacologia , Piridinas/farmacologia , Aminopiridinas , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Proliferação de Células/efeitos dos fármacos , Crizotinibe , Cristalografia por Raios X , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioma/patologia , Humanos , Lactamas , Lactamas Macrocíclicas/química , Camundongos , Modelos Moleculares , Transdução de Sinais/efeitos dos fármacos
12.
Int J Nanomedicine ; 10: 1155-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25709439

RESUMO

Magnetic resonance imaging (MRI) contrast agents based on chitosan derivatives have great potential for diagnosing diseases. However, stable tumor-targeted MRI contrast agents using micelles prepared from high molecular weight chitosan derivatives are seldom reported. In this study, we developed a novel tumor-targeted MRI vehicle via superparamagnetic iron oxide nanoparticles (SPIONs) encapsulated in self-aggregating polymeric folate-conjugated N-palmitoyl chitosan (FAPLCS) micelles. The tumor-targeting ability of FAPLCS/SPIONs was demonstrated in vitro and in vivo. The results of dynamic light scattering experiments showed that the micelles had a relatively narrow size distribution (136.60±3.90 nm) and excellent stability. FAPLCS/SPIONs showed low cytotoxicity and excellent biocompatibility in cellular toxicity tests. Both in vitro and in vivo studies demonstrated that FAPLCS/SPIONs bound specifically to folate receptor-positive HeLa cells, and that FAPLCS/SPIONs accumulated predominantly in established HeLa-derived tumors in mice. The signal intensities of T2-weighted images in established HeLa-derived tumors were reduced dramatically after intravenous micelle administration. Our study indicates that FAPLCS/SPION micelles can potentially serve as safe and effective MRI contrast agents for detecting tumors that overexpress folate receptors.


Assuntos
Quitosana/análogos & derivados , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Micelas , Neoplasias/patologia , Animais , Quitosana/química , Quitosana/farmacocinética , Meios de Contraste/química , Meios de Contraste/farmacocinética , Ácido Fólico/química , Ácido Fólico/farmacocinética , Células HeLa , Humanos , Camundongos
13.
Protein Sci ; 23(10): 1332-40, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25043846

RESUMO

PI3Kα remains an attractive target for the development of anticancer targeted therapy. A number of p110α crystal structures in complex with the nSH2-iSH2 fragment of p85 regulatory subunit have been reported, including a few small molecule co-crystal structures, but the utilization of this crystal form is limited by low diffraction resolution and a crystal packing artifact that partially blocks the ATP binding site. Taking advantage of recent data on the functional characterization of the lipid binding properties of p110α, we designed a set of novel constructs allowing production of isolated stable p110α subunit missing the Adapter Binding Domain and lacking or featuring a modified C-terminal lipid binding motif. While this protein is not catalytically competent to phosphorylate its substrate PIP2, it retains ligand binding properties as indicated by direct binding studies with a pan-PI3Kα inhibitor. Additionally, we determined apo and PF-04691502 bound crystal structures of the p110α (105-1048) subunit at 2.65 and 2.85 Å, respectively. Comparison of isolated p110α(105-1048) with the p110α/p85 complex reveals a high degree of structural similarity, which validates suitability of this catalytically inactive p110α for iterative SBDD. Importantly, this crystal form of p110α readily accommodates the binding of noncovalent inhibitor by means of a fully accessible ATP site. The strategy presented here can be also applied to structural studies of other members of PI3KIA family.


Assuntos
Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Fosfolipídeos/metabolismo , Piridonas/química , Piridonas/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Domínio Catalítico , Classe I de Fosfatidilinositol 3-Quinases , Clonagem Molecular , Cristalização , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Inibidores de Fosfoinositídeo-3 Quinase , Estrutura Terciária de Proteína , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/química , Subunidades Proteicas/genética , Relação Estrutura-Atividade , Ressonância de Plasmônio de Superfície
14.
J Med Chem ; 57(11): 4720-44, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24819116

RESUMO

Although crizotinib demonstrates robust efficacy in anaplastic lymphoma kinase (ALK)-positive non-small-cell lung carcinoma patients, progression during treatment eventually develops. Resistant patient samples revealed a variety of point mutations in the kinase domain of ALK, including the L1196M gatekeeper mutation. In addition, some patients progress due to cancer metastasis in the brain. Using structure-based drug design, lipophilic efficiency, and physical-property-based optimization, highly potent macrocyclic ALK inhibitors were prepared with good absorption, distribution, metabolism, and excretion (ADME), low propensity for p-glycoprotein 1-mediated efflux, and good passive permeability. These structurally unusual macrocyclic inhibitors were potent against wild-type ALK and clinically reported ALK kinase domain mutations. Significant synthetic challenges were overcome, utilizing novel transformations to enable the use of these macrocycles in drug discovery paradigms. This work led to the discovery of 8k (PF-06463922), combining broad-spectrum potency, central nervous system ADME, and a high degree of kinase selectivity.


Assuntos
Antineoplásicos/síntese química , Encéfalo/metabolismo , Lactamas Macrocíclicas/síntese química , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Aminopiridinas , Quinase do Linfoma Anaplásico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Cristalografia por Raios X , Resistencia a Medicamentos Antineoplásicos , Humanos , Lactamas , Lactamas Macrocíclicas/farmacocinética , Lactamas Macrocíclicas/farmacologia , Camundongos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Mutação , Células NIH 3T3 , Pirazóis , Ratos , Receptores Proteína Tirosina Quinases/genética , Estereoisomerismo , Relação Estrutura-Atividade
15.
J Med Chem ; 57(4): 1170-87, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24432909

RESUMO

Crizotinib (1), an anaplastic lymphoma kinase (ALK) receptor tyrosine kinase inhibitor approved by the U.S. Food and Drug Administration in 2011, is efficacious in ALK and ROS positive patients. Under pressure of crizotinib treatment, point mutations arise in the kinase domain of ALK, resulting in resistance and progressive disease. The successful application of both structure-based and lipophilic-efficiency-focused drug design resulted in aminopyridine 8e, which was potent across a broad panel of engineered ALK mutant cell lines and showed suitable preclinical pharmacokinetics and robust tumor growth inhibition in a crizotinib-resistant cell line (H3122-L1196M).


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Mutação Puntual , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico , Crizotinibe , Humanos
16.
N Engl J Med ; 368(25): 2395-401, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23724914

RESUMO

Crizotinib, an inhibitor of anaplastic lymphoma kinase (ALK), has also recently shown efficacy in the treatment of lung cancers with ROS1 translocations. Resistance to crizotinib developed in a patient with metastatic lung adenocarcinoma harboring a CD74-ROS1 rearrangement who had initially shown a dramatic response to treatment. We performed a biopsy of a resistant tumor and identified an acquired mutation leading to a glycine-to-arginine substitution at codon 2032 in the ROS1 kinase domain. Although this mutation does not lie at the gatekeeper residue, it confers resistance to ROS1 kinase inhibition through steric interference with drug binding. The same resistance mutation was observed at all the metastatic sites that were examined at autopsy, suggesting that this mutation was an early event in the clonal evolution of resistance. (Funded by Pfizer and others; ClinicalTrials.gov number, NCT00585195.).


Assuntos
Adenocarcinoma/genética , Resistência a Medicamentos/genética , Neoplasias Pulmonares/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Translocação Genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Crizotinibe , Evolução Fatal , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Mutação , Conformação Proteica , Proteínas Tirosina Quinases/química , Proteínas Proto-Oncogênicas/química , Relação Estrutura-Atividade
17.
Protein Sci ; 21(12): 1885-96, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23033253

RESUMO

The heterodimer HIF-1α (hypoxia inducible factor)/HIF-ß (also known as ARNT-aryl hydrocarbon nuclear translocator) is a key mediator of cellular response to hypoxia. The interaction between these monomer units can be modified by the action of small molecules in the binding interface between their C-terminal heterodimerization (PasB) domains. Taking advantage of the presence of several cysteine residues located in the allosteric cavity of HIF-1α PasB domain, we applied a cysteine-based reactomics "hotspot identification" strategy to locate regions of HIF-1α PasB domain critical for its interaction with ARNT. COMPOUND 5 was identified using a mass spectrometry-based primary screening strategy and was shown to react specifically with Cys255 of the HIF-1α PasB domain. Biophysical characterization of the interaction between PasB domains of HIF-1α and ARNT revealed that covalent binding of COMPOUND 5 to Cys255 reduced binding affinity between HIF-1α and ARNT PasB domains approximately 10-fold. Detailed NMR structural analysis of HIF-1α-PasB-COMPOUND 5 conjugate showed significant local conformation changes in the HIF-1α associated with key residues involved in the HIF-1α/ARNT PasB domain interaction as revealed by the crystal structure of the HIF-1α/ARNT PasB heterodimer. Our screening strategy could be applied to other targets to identify pockets surrounding reactive cysteines suitable for development of small molecule modulators of protein function.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Cisteína/química , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Translocador Nuclear Receptor Aril Hidrocarboneto/antagonistas & inibidores , Translocador Nuclear Receptor Aril Hidrocarboneto/química , Cisteína/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/química , Modelos Moleculares , Ligação Proteica/efeitos dos fármacos , Conformação Proteica/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos
18.
Proc Natl Acad Sci U S A ; 109(45): 18281-9, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-22988103

RESUMO

Analyses of compounds in clinical development have shown that ligand efficient-molecules with privileged physical properties and low dose are less likely to fail in the various stages of clinical testing, have fewer postapproval withdrawals, and are less likely to receive black box safety warnings. However, detailed side-by-side examination of molecular interactions and properties within single drug classes are lacking. As a class, VEGF receptor tyrosine kinase inhibitors (VEGFR TKIs) have changed the landscape of how cancer is treated, particularly in clear cell renal cell carcinoma, which is molecularly linked to the VEGF signaling axis. Despite the clear role of the molecular target, member molecules of this validated drug class exhibit distinct clinical efficacy and safety profiles in comparable renal cell carcinoma clinical studies. The first head-to-head randomized phase III comparative study between active VEGFR TKIs has confirmed significant differences in clinical performance [Rini BI, et al. (2011) Lancet 378:193-1939]. To elucidate how fundamental drug potency-efficiency is achieved and impacts differentiation within the VEGFR TKI class, we determined potencies, time dependence, selectivities, and X-ray structures of the drug-kinase complexes using a VEGFR2 TK construct inclusive of the important juxtamembrane domain. Collectively, the studies elucidate unique drug-kinase interactions that are dependent on distinct juxtamembrane domain conformations, resulting in significant potency and ligand efficiency differences. The identified structural trends are consistent with in vitro measurements, which translate well to clinical performance, underscoring a principle that may be broadly applicable to prospective drug design for optimal in vivo performance.


Assuntos
Conformação Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/química , Carcinoma de Células Renais/tratamento farmacológico , Ensaios Clínicos como Assunto , Cristalografia por Raios X , Intervalo Livre de Doença , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Neoplasias Renais/tratamento farmacológico , Modelos Moleculares , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Estrutura Terciária de Proteína , Resultado do Tratamento , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
19.
J Med Chem ; 55(18): 8091-109, 2012 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-22924734

RESUMO

The c-MET receptor tyrosine kinase is an attractive oncology target because of its critical role in human oncogenesis and tumor progression. An oxindole hydrazide hit 6 was identified during a c-MET HTS campaign and subsequently demonstrated to have an unusual degree of selectivity against a broad array of other kinases. The cocrystal structure of the related oxindole hydrazide c-MET inhibitor 10 with a nonphosphorylated c-MET kinase domain revealed a unique binding mode associated with the exquisite selectivity profile. The chemically labile oxindole hydrazide scaffold was replaced with a chemically and metabolically stable triazolopyrazine scaffold using structure based drug design. Medicinal chemistry lead optimization produced 2-(4-(1-(quinolin-6-ylmethyl)-1H-[1,2,3]triazolo[4,5-b]pyrazin-6-yl)-1H-pyrazol-1-yl)ethanol (2, PF-04217903), an extremely potent and exquisitely selective c-MET inhibitor. 2 demonstrated effective tumor growth inhibition in c-MET dependent tumor models with good oral PK properties and an acceptable safety profile in preclinical studies. 2 progressed to clinical evaluation in a Phase I oncology setting.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Pirazinas/farmacologia , Triazóis/farmacologia , Sequência de Aminoácidos , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Indóis/química , Modelos Moleculares , Dados de Sequência Molecular , Oxindóis , Conformação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-met/química , Proteínas Proto-Oncogênicas c-met/metabolismo , Pirazinas/química , Pirazinas/metabolismo , Especificidade por Substrato , Triazóis/química , Triazóis/metabolismo
20.
J Med Chem ; 55(10): 4728-39, 2012 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-22554206

RESUMO

The P21-activated kinases (PAK) are emerging antitumor therapeutic targets. In this paper, we describe the discovery of potent PAK inhibitors guided by structure-based drug design. In addition, the efflux of the pyrrolopyrazole series was effectively reduced by applying multiple medicinal chemistry strategies, leading to a series of PAK inhibitors that are orally active in inhibiting tumor growth in vivo.


Assuntos
Antineoplásicos/síntese química , Pirazóis/síntese química , Pirróis/síntese química , Quinases Ativadas por p21/antagonistas & inibidores , Administração Oral , Amidas/síntese química , Amidas/farmacocinética , Amidas/farmacologia , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Carbamatos/química , Carbamatos/farmacocinética , Carbamatos/farmacologia , Cristalografia por Raios X , Cães , Humanos , Ligação de Hidrogênio , Camundongos , Modelos Moleculares , Conformação Molecular , Permeabilidade , Pirazóis/farmacocinética , Pirazóis/farmacologia , Pirróis/farmacocinética , Pirróis/farmacologia , Ratos , Estereoisomerismo , Relação Estrutura-Atividade , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
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