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1.
J Appl Toxicol ; 35(2): 199-204, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24677158

RESUMO

Many systemic drugs can induce ocular toxicity and several ocular side-effects have been identified in clinical studies. However, it is difficult to detect ocular toxicity in preclinical studies because of the lack of appropriate evaluation methods. Optical coherence tomography (OCT) is useful because it can provide real-time images throughout a study period, whereas histopathology only provides images of sacrificed animals. Using OCT alongside histopathology, attempts were made to find effective approaches for screening of drug-induced ocular toxicity in monkeys. Such approaches could be used in preclinical studies prior to human trials. Six male cynomolgus monkeys (Macaca fascicularis Raffles) were orally administered one of six candidate MAPK/ERK kinase (MEK) inhibitors. Central serous chorioretinopathy, a known side-effect of such inhibitors, was identified in four monkeys by OCT. Artifacts generated during tissue processing meant that histopathology could not detect edematous changes. Thus, OCT is a useful tool to detect ocular toxicity which cannot be detected by histopathology in preclinical studies.


Assuntos
Coriorretinopatia Serosa Central/diagnóstico , Tomografia de Coerência Óptica/métodos , Animais , Coriorretinopatia Serosa Central/induzido quimicamente , Coriorretinopatia Serosa Central/patologia , Inibidores Enzimáticos/toxicidade , MAP Quinase Quinase Quinases/antagonistas & inibidores , Macaca fascicularis , Masculino , Retina/efeitos dos fármacos , Retina/patologia
2.
Invest New Drugs ; 31(6): 1458-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24068620

RESUMO

Epidermal growth factor receptor (EGFR) gene mutations activate the KRAS-RAF-MEK-ERK pathway in lung cancer cells. EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib induce apoptosis of cancer cells, but prolonged treatment is often associated with acquired resistance. Here, we identified a novel MEK1/2 inhibitor, CZ0775, and compared its cytotoxic effects to those of AZD6244 (selumetinib) in non-small cell lung cancer (NSCLC) cell lines harboring EGFR mutations. The lapatinib-sensitive HCC827 and PC9 and lapatinib-resistant H1650 and H1975 cell lines showed poor responses to CZ0775 and AZD6244 monotherapy with an IC50 > 10 µM. By contrast, combination treatment with lapatinib and CZ0775 inhibited cell proliferation and produced a 2-fold higher number of annexin V-labeled cells than lapatinib alone in H1975 cells. Furthermore, combination treatment decreased phosphorylated extracellular signal related kinase (p-ERK) and survivin levels and upregulated the expression of the pro-apoptotic protein BIM. siRNA-mediated BIM depletion reduced caspase-3 activity (~40%) in lapatinib and CZ0775 treated H1975 cells. An in vitro ERK activity assay showed that p-ERK levels were approximately a 3-fold lower in H1975 cells treated with CZ0775 and lapatinib combination than in cells treated with lapatinib alone. CZ0775 was more cytotoxic than AZD6244 when used in combination with lapatinib. Our results suggest that combination treatment with CZ0774 and EGFR inhibitors is a promising therapeutic approach for the treatment of EGFR-TKI-resistant lung cancers and its effect is mediated by the inhibition of ERK and the induction of BIM.


Assuntos
Antineoplásicos/administração & dosagem , Receptores ErbB/antagonistas & inibidores , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Inibidores de Proteínas Quinases/administração & dosagem , Piridonas/administração & dosagem , Sulfonamidas/administração & dosagem , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Benzimidazóis/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sinergismo Farmacológico , Receptores ErbB/genética , Gefitinibe , Humanos , Lapatinib , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/metabolismo , Mutação , Proteínas Proto-Oncogênicas/metabolismo , Quinazolinas/administração & dosagem
3.
Oncotarget ; 8(25): 41387-41400, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-28574827

RESUMO

Primary or acquired resistance to MEK inhibitors has been a barrier to successful treatment with MEK inhibitors in many tumors. In this study, we analyzed genome-wide gene expression profiling data from 6 sensitive and 6 resistant cell lines to identify candidate genes whose expression changes are associated with responses to a MEK inhibitor, selumetinib (AZD6244). Of 62 identified differentially expressed genes, we selected Immunoglobulin Transcription Factor 2, also known as transcription factor 4 as a potential drug resistance marker for further analysis. This was because the ITF-2 expression increase in resistant cell lines was relatively high and a previous study has suggested that ITF-2 functions as an oncogene in human colon cancers. We also established an AZD6244 resistant cell line (M14/AZD-3) from an AZD6244 sensitive M14 cell line. The expression of the ITF-2 was elevated both in primary AZD6244 resistant cell line, LOX-IMVI and acquired resistant cell line, M14/AZD-3. Targeted silencing of ITF-2 by siRNA significantly enhanced susceptibility to AZD6244 in resistant cells. Wnt/ß-catenin pathway was activated through direct interaction of p-ERK and GSK3ß. Our results suggest that up-regulation of the ITF-2 gene expression is associated with cellular resistance to MEK inhibitors, and activation of Wnt signaling pathway through interaction of p-ERK and GSK3ß seems to be a mechanism for increase of ITF-2.


Assuntos
Benzimidazóis/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator de Transcrição 4/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Perfilação da Expressão Gênica/métodos , Células HL-60 , Humanos , Células K562 , Melanoma/genética , Melanoma/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
4.
J Med Chem ; 59(6): 2551-66, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26901666

RESUMO

Benzazole derivatives with a flexible aryl group bonded through a one-atom linker as a new scaffold for a corticotropin-releasing factor 1 (CRF1) receptor antagonist were designed, synthesized, and evaluated. We expected that structural diversity could be expanded beyond that of reported CRF1 receptor antagonists. In a structure-activity relationship study, 4-chloro-N(2)-(4-chloro-2-methoxy-6-methylphenyl)-1-methyl-N(7),N(7)-dipropyl-1H-benzimidazole-2,7-diamine 29g had the most potent binding activity against a human CRF1 receptor and the antagonistic activity (IC50 = 9.5 and 88 nM, respectively) without concerns regarding cytotoxicity at 30 µM. Potent CRF1 receptor-binding activity in brain in an ex vivo test and suppression of stress-induced activation of the hypothalamus-pituitary-adrenocortical (HPA) axis were also observed at 138 µmol/kg of compound 29g after oral administration in mice. Thus, the newly designed benzimidazole 29g showed in vivo CRF1 receptor antagonistic activity and good brain penetration, indicating that it is a promising lead for CRF1 receptor antagonist drug discovery research.


Assuntos
Benzimidazóis/antagonistas & inibidores , Benzimidazóis/farmacologia , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Hormônio Adrenocorticotrópico/metabolismo , Animais , Química Encefálica/efeitos dos fármacos , Células CHO , Cricetinae , Cricetulus , Desenho de Fármacos , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Camundongos , Modelos Moleculares , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Relação Estrutura-Atividade
5.
J Med Chem ; 59(2): 733-49, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26701356

RESUMO

We report herein the discovery and optimization of 3-amino-1,5-dihydro-4H-pyrazolopyridin-4-one TYK2 inhibitors. High-throughput screening against TYK2 and JAK1-3 provided aminoindazole derivative 1 as a hit compound. Scaffold hopping of the aminoindazole core led to the discovery of 3-amino-1,5-dihydro-4H-pyrazolopyridin-4-one derivative 3 as a novel chemotype of TYK2 inhibitors. Interestingly, initial SAR study suggested that this scaffold could have a vertically flipped binding mode, which prompted us to introduce a substituent at the 7-position as a moiety directed toward the solvent-exposed region. Introduction of a 1-methyl-3-pyrazolyl moiety at the 7-position resulted in a dramatic increase in TYK2 inhibitory activity, and further optimization led to the discovery of 20. Compound 20 inhibited IL-23-induced IL-22 production in a rat PD assay, as well as inhibited IL-23 signaling in human PBMC. Furthermore, 20 showed selectivity for IL-23 signaling inhibition against GM-CSF, demonstrating the unique cytokine selectivity of the novel TYK2 inhibitor.


Assuntos
Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , TYK2 Quinase/antagonistas & inibidores , Animais , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Triagem em Larga Escala , Humanos , Interleucina-23/farmacologia , Interleucinas/biossíntese , Janus Quinase 2/antagonistas & inibidores , Células Jurkat , Masculino , Modelos Moleculares , Monócitos/efeitos dos fármacos , Monócitos/enzimologia , Inibidores de Proteínas Quinases/farmacocinética , Ratos , Ratos Endogâmicos Lew , Relação Estrutura-Atividade , Interleucina 22
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