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1.
Anticancer Res ; 39(9): 4805-4810, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31519582

RESUMO

BACKGROUND/AIM: Ro 90-7501 has been reported as an inhibitor of the amyloid ß42 fibril assembly that is associated with Alzheimer's disease. The present study aimed to elucidate the radiosensitizing effects of Ro 90-7501 and focused on ATM signaling after irradiation. MATERIALS AND METHODS: Clonogenic survival, apoptosis, and cell-cycle assays as well as western blotting were performed in HeLa cells treated with irradiation and Ro 90-7501. Tumor growth delay assay was also performed using BALB/c-nu mice. RESULTS: The combination of irradiation with Ro 90-7501 showed significant radiosensitizing effects in clonogenic survival and tumor growth delay assays. Ro 90-7501 significantly increased apoptosis and impaired cell cycle after irradiation. Western blotting showed that Ro 90-7501 suppressed the phosphorylation of ATM and its downstream proteins, such as H2AX, Chk1, and Chk2, after irradiation. CONCLUSION: Ro 90-7501 inhibits DNA damage response by inhibiting ATM and has significant radiosensitizing effects on cervical cancer cells.


Assuntos
Aminas/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Benzimidazóis/farmacologia , Radiossensibilizantes/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Neoplasias do Colo do Útero/metabolismo
2.
N Engl J Med ; 381(12): 1136-1147, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31532960

RESUMO

BACKGROUND: Maribavir is a benzimidazole riboside with activity against cytomegalovirus (CMV). The safety and efficacy of maribavir for preemptive treatment of CMV infection in transplant recipients is not known. METHODS: In a phase 2, open-label, maribavir dose-blinded trial, recipients of hematopoietic-cell or solid-organ transplants (≥18 years of age, with CMV reactivation [1000 to 100,000 DNA copies per milliliter]) were randomly assigned to receive maribavir at a dose of 400, 800, or 1200 mg twice daily or the standard dose of valganciclovir for no more than 12 weeks. The primary efficacy end point was the percentage of patients with a response to treatment, defined as confirmed undetectable CMV DNA in plasma, within 3 weeks and 6 weeks after the start of treatment. The primary safety end point was the incidence of adverse events that occurred or worsened during treatment. RESULTS: Of the 161 patients who underwent randomization, 159 received treatment, and 156 had postbaseline data available - 117 in the maribavir group and 39 in the valganciclovir group. The percentage of patients with postbaseline data available who had a response to treatment within 3 weeks was 62% among those who received maribavir and 56% among those who received valganciclovir. Within 6 weeks, 79% and 67% of patients, respectively, had a response (risk ratio, 1.20; 95% confidence interval, 0.95 to 1.51). The percentages of patients with a response to treatment were similar among the maribavir dose groups. Two patients who had a response to treatment had a recurrence of CMV infection within 6 weeks after starting maribavir at a dose of 800 mg twice daily; T409M resistance mutations in CMV UL97 protein kinase developed in both patients. The incidence of serious adverse events that occurred or worsened during treatment was higher in the maribavir group than in the valganciclovir group (52 of 119 patients [44%] vs. 13 of 40 [32%]). A greater percentage of patients in the maribavir group discontinued the trial medication because of an adverse event (27 of 119 [23%] vs. 5 of 40 [12%]). A higher incidence of gastrointestinal adverse events was reported with maribavir, and a higher incidence of neutropenia was reported with valganciclovir. CONCLUSIONS: Maribavir at a dose of at least 400 mg twice daily had efficacy similar to that of valganciclovir for clearing CMV viremia among recipients of hematopoietic-cell or solid-organ transplants. A higher incidence of gastrointestinal adverse events - notably dysgeusia - and a lower incidence of neutropenia were found in the maribavir group. (Funded by ViroPharma/Shire Development; EudraCT number, 2010-024247-32.).


Assuntos
Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Citomegalovirus/fisiologia , Ribonucleosídeos/uso terapêutico , Valganciclovir/uso terapêutico , Viremia/tratamento farmacológico , Adulto , Idoso , Aloenxertos , Antivirais/efeitos adversos , Antivirais/farmacologia , Benzimidazóis/efeitos adversos , Benzimidazóis/farmacologia , Citomegalovirus/efeitos dos fármacos , Infecções por Citomegalovirus/virologia , Disgeusia/induzido quimicamente , Feminino , Gastroenteropatias/induzido quimicamente , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Transplante de Órgãos/efeitos adversos , Ribonucleosídeos/efeitos adversos , Ribonucleosídeos/farmacologia , Valganciclovir/efeitos adversos , Valganciclovir/farmacologia , Ativação Viral/efeitos dos fármacos
3.
Plant Dis ; 103(10): 2536-2540, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31424998

RESUMO

Fusarium head blight, also called scab, is caused by Fusarium graminearum and is one of the most important destructive diseases of wheat. The frequency of carbendazim resistance in 1,132 isolates of F. graminearum recovered from fields in different regions of Henan Province in 2016, 2017, and 2018 was determined. A total of 31 F. graminearum isolates resistant to carbendazim were detected, including 30 moderately resistant isolates and one highly resistant isolate. The frequency of resistance of F. graminearum isolates to carbendazim was 2.7%. The range of effective concentration (EC50) values of 1,101 sensitive isolates and 30 moderately resistant isolates was 0.08 to 0.98 µg ml-1 and 2.73 to 13.28 µg ml-1, respectively. The mean ± SD EC50 value was 0.55 ± 0.13 µg ml-1 and 5.61 ± 2.58 µg ml-1, respectively. The EC50 value of the highly resistant isolate was 21.12 µg ml-1. Point mutation types of the carbendazim-resistant isolates were characterized by cloning the ß2-tubulin gene of 31 resistant isolates. Three point mutation types at amino acids F167Y, E198Q, and E198L in the ß2-tubulin gene of resistant isolates were identified. Among 31 resistant isolates, the frequency of point mutation types in F167Y, E198Q, and E198L of the ß2-tubulin gene was 71.0, 25.8, and 3.2%, respectively. The data indicate that F. graminearum has developed resistance to carbendazim in Henan Province, and single point mutations at amino acid F167Y were the predominant type of mutation detected.


Assuntos
Benzimidazóis , Carbamatos , Farmacorresistência Fúngica , Fusarium , Triticum , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Farmacorresistência Fúngica/genética , Fungicidas Industriais , Fusarium/efeitos dos fármacos , Fusarium/genética , Genes de Plantas/genética , Mutação Puntual , Triticum/microbiologia , Tubulina (Proteína)/genética
4.
Exp Parasitol ; 205: 107734, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31394093

RESUMO

Parasitism by Haemonchus contortus is one of the main limiting factors in small ruminant production around the globe. Although several studies suggest the use of integrated management practices, these parasites have been controlled essentially with synthetic anthelmintic drugs. The resistance mechanism against the imidazothiazole derivative levamisole in Haemonchus contortus has not been fully described. Recently, resistance was associated with a 63bp deletion in the Hco-acr-8b gene that encodes a subunit for a nicotinic acetylcholine receptor. This study aimed to standardize a real time PCR (qPCR) protocol for levamisole resistance diagnosis in H. contortus populations based on this polymorphism and use it to characterize 23 field H. contortus populations obtained from different localities of Ceará State, Northeast Brazil. In addition, two populations of H. contortus were used as a standard of susceptibility and resistance, Inbred Strain Edinburgh (ISE) and Kokstad, respectively. Larval development tests (LDT) were performed on five field isolates and both EC50 and EC95 were estimated. LDT EC95 values provided a wider interval between susceptible and resistant populations than EC50 values (EC95 = 1.96-57.93 µM; EC50 = 0.05-0.39 µM), and were found to be more appropriate for differentiating them. Real time PCR results showed resistance allele frequencies ranged from 20.9 to 76.7%. Our results suggest that levamisole resistance may be present in field populations but it is not as widespread as benzimidazole resistance. This methodology may be useful to monitor levamisole resistance in field populations of H. contortus.


Assuntos
Antinematódeos/farmacologia , Resistência a Medicamentos/genética , Haemonchus/efeitos dos fármacos , Levamisol/farmacologia , Animais , Benzimidazóis/farmacologia , DNA de Helmintos/isolamento & purificação , Fezes/parasitologia , Frequência do Gene/genética , Hemoncose/tratamento farmacológico , Hemoncose/parasitologia , Hemoncose/veterinária , Haemonchus/genética , Haemonchus/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Receptores Colinérgicos/efeitos dos fármacos , Receptores Nicotínicos/efeitos dos fármacos , Alinhamento de Sequência/veterinária , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Tetramizol/farmacologia
5.
Eur J Med Chem ; 181: 111574, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400705

RESUMO

A series of novel hydroxyethylaminomethylbenzimidazole analogs 5a-y were synthesized and evaluated for their IL-5 inhibitory activity using pro-B Y16 cell line. Among them, 2-(((4-(cyclohexylmethoxy)-1H-benzo[d]imidazol-2-yl)methyl)amino)butan-1-ol (5e, 94.3% inhibition at 30 µM, IC50 = 3.5 µM, cLogP = 4.132) and 3-cyclohexyl-2-(((4-(cyclohexylmethoxy)-1H-benzo[d]imidazol-2-yl)methyl)amino) propan-1-ol (5k, 94.7% inhibition at 30 µM, IC50 = 5.0 µM, cLogP = 6.253) showed the most potent inhibitory activity. The essential feature of SAR (Fig. 5) indicated that the chromenone ring can be replaced by a benzimidazole ring to maintain the inhibitory activity. In addition, the hydroxyethylaminomethyl group was suitable for the IL-5 inhibitory activity. Moreover, the hydrophobic substituents on carbon play an important role in the IL-5 inhibitory activity of these analogs. However, N-substituted analogs did not improve inhibitory activity. In addition, MTT assay of 5e and 5k with normal B lymphoblasts revealed that they had no significant effects on cell viability.


Assuntos
Benzimidazóis/química , Benzimidazóis/farmacologia , Interleucina-5/antagonistas & inibidores , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Modelos Moleculares , Relação Estrutura-Atividade
6.
Pestic Biochem Physiol ; 158: 128-134, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378348

RESUMO

Indoleacetic acid (IAA)-carbendazim was synthesized to assess whether this conjugate could retain the fungicidal activity of carbendazim and gain root-inducing properties upon the addition of an indoleacetic acid group. An indoor virulence test demonstrated that the conjugate retained the fungicidal activity of carbendazim towards Cylindrocladium parasiticum. The conjugate was detected in roots after soaking Ricinus communis L. leaves into a solution of the IAA-carbendazim, which confirmed its phloem mobility. The activities of the cellulase, polygalacturonase and xylanase produced by Cylindrocladium parasiticum treated with different concentrations of the conjugate were determined, and the peak activities appeared at 72 h or 96 h. More importantly, the conjugate showed the ability to promote root growth. These results revealed that indoleacetic acid-carbendazim may be useful in preventing Cylindrocladium parasiticum and other diseases.


Assuntos
Ascomicetos/efeitos dos fármacos , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Fungicidas Industriais/farmacologia , Ácidos Indolacéticos/farmacologia , Celulase/metabolismo , Floema/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Poligalacturonase/metabolismo , Ricinus/efeitos dos fármacos
7.
Pestic Biochem Physiol ; 158: 18-24, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378355

RESUMO

Outbreaks of bitter rot were observed in three commercial apple orchards in Illinois despite best management efforts during the 2018 production season. Three isolates from symptomatic fruit from these orchards and two isolates from an orchard in South Carolina were identified to the species level using morphological tools and calmodulin, glyceraldehyde-3-phosphate dehydrogenase, and beta-tubulin gene sequences. The isolates from Illinois were identified as Colletotrichum siamense of the Colletotrichum gloeosporioides species complex and the ones from South Carolina as Colletotrichum fioriniae and Colletotrichum fructicola of the Colletotrichum acutatum and the C. gloeosporioides species complex, respectively. Two of the three C. siamense isolates from Illinois were resistant to azoxystrobin and thiophanate-methyl as determined in mycelial growth tests in vitro. EC50 values were >100 µg/ml for both fungicides. One isolate was only resistant to azoxystrobin. None of the isolates from South Carolina was resistant to either of the two compounds. All five isolates were sensitive to fludioxonil (EC50 values <0.1 µg/ml), propiconazole (EC50 values ranged from 0.15 to 0.36 µg/ml), and benzovindiflupyr (EC50 values ranged from <0.1 to 0.33 µg/ml). Resistance in C. siamense to azoxystrobin and thiophanate-methyl was confirmed in detached fruit studies using apples treated with label rates of registered product. Resistance to thiophanate-methyl in C. siamense was based on E198A mutation in b-tubulin gene, whereas resistance to azoxystrobin was based on G143A in cytochrome b (CYTB). One isolate resistant to azoxystrobin possessed no amino acid variation in CYTB. This study shows that quinone outside inhibitor fungicide resistance in Colletotrichum from apple has emerged and is being selected for in Illinois apple orchards by current spray strategies. Resistance monitoring may alert growers to potential threats, but the employment of molecular tools based on current knowledge of resistance mechanisms will provide incomplete results.


Assuntos
Colletotrichum/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Malus/microbiologia , Benzimidazóis/farmacologia , Colletotrichum/genética , Citocromos b/genética , Citocromos b/metabolismo , Dioxóis/farmacologia , Farmacorresistência Fúngica/genética , Frutas/microbiologia , Malus/genética , Norbornanos/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Estrobilurinas/farmacologia , Tiofanato/farmacologia , Triazóis/farmacologia
8.
Vet Parasitol ; 271: 31-37, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31303200

RESUMO

The recovery of fenbendazole efficacy against Haemonchus contortus was attempted in a sheep intensive production system, using a strategy of population replacement in which the initial absolute efficacy of fenbendazole was 0%. The strategy was based on managing the parasite populations in refugia. Firstly, the resistant parasite population was reduced by means of anthelmintic treatments with efficacious drugs (Phase I), then a new, susceptible population was introduced in summer by way of artificially infected lambs at weaning, which were left to graze on the experimental pasture for eleven months (Phase II). Lastly, the impact of the replacement strategy, in terms of benzimidazole efficacy, was measured (Phase III). Faecal egg counts from permanent lambs and worm burdens as a measure of pasture infectivity from tracer lambs were determined throughout the study. During Phase I, faecal egg counts diminished from a peak of 2968 (300-7740) epg to 0 epg at the end, while adult worm burdens of H. contortus were reduced from 2625 (800-5100) to 0, which showed that the treatment strategy used in Phase I was effective in reducing the resistant population. These parameters also showed that good levels of pasture contamination and infectivity were achieved in Phase II, as faecal egg counts of up to 7275 (3240-13080) epg and adult worm burdens of 500 (200-800) H. contortus were reached. The absolute benzimidazole efficacy on H. contortus estimated at 16 months post-population replacement (Phase III) was 97.58%. The results lead to the conclusion that the recovery of anthelmintic efficacy of fenbendazole against a resistant population of H. contortus may be achieved by means of a strategy based on management of refugia and a subsequent introduction of a susceptible population. This strategy might be translatable to other resistant nematode genera.


Assuntos
Criação de Animais Domésticos/métodos , Resistência a Medicamentos , Fenbendazol/farmacologia , Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Criação de Animais Domésticos/normas , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Fenbendazol/uso terapêutico , Hemoncose/tratamento farmacológico , Hemoncose/prevenção & controle , Ovinos
9.
Eur J Med Chem ; 180: 121-133, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31301563

RESUMO

Phenyl- and bioisosteric ferrocenyl-derived aminoquinoline-benzimidazole hybrid compounds were synthesised and evaluated for their in vitro antiplasmodial activity against the chloroquine-sensitive NF54 and multi-drug resistant K1 strains of the human malaria parasite, Plasmodium falciparum. All compounds were active against the two strains, generally showing enhanced activity in the K1 strain, with resistance indices less than 1. Cytotoxicity studies using Chinese hamster ovarian cells revealed that the hybrids were relatively non-cytotoxic and demonstrated selective killing of the parasite. Based on favourable in vitro antiplasmodial and cytotoxicity data, the most active phenyl (4c) and ferrocenyl (5b) hybrids were tested in vivo against the rodent Plasmodium berghei mouse model. Both compounds caused a reduction in parasitemia relative to the control, with 5c displaying superior activity (92% reduction in parasitemia at 4 × 50 mg/kg oral doses). The most active phenyl and ferrocenyl derivatives showed inhibition of ß-haematin formation in a NP-40 detergent-mediated assay, indicating a possible contributing mechanism of antiplasmodial action. The most active ferrocenyl hybrid did not display appreciable reactive oxygen species (ROS) generation in a ROS-induced DNA cleavage gel electrophoresis study. The compounds were also screened for their in vitro activity against Mycobacterium tuberculosis. The hybrids containing a more hydrophobic substituent had enhanced activity (<32.7 µM) compared to those with a less hydrophobic substituent (>62.5 µM).


Assuntos
Antibacterianos/farmacologia , Antimaláricos/farmacologia , Benzimidazóis/farmacologia , Compostos Ferrosos/farmacologia , Malária/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Quinolinas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antimaláricos/síntese química , Antimaláricos/química , Benzimidazóis/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Compostos Ferrosos/química , Camundongos , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Quinolinas/química , Relação Estrutura-Atividade
10.
Plant Dis ; 103(9): 2385-2391, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31313639

RESUMO

Stimulatory effects of low doses of fungicides on the virulence of phytopathogens have profound implications for applications of fungicides. The present study demonstrated that carbendazim sprayed at 0.001 to 0.03 µg/ml had stimulatory effects on the virulence of mycelia of Botrytis cinerea, and the maximum percent stimulations were 15.5 and 21.4% for isolates HB459 and HB536, respectively. Potato dextrose agar (PDA) amended with carbendazim at 0.01, 0.02, and 0.05 µg/ml inhibited mycelial growth of isolate HB536 by 0.8, 10.0, and 30.6%, respectively. However, after the inhibited mycelia were inoculated on cucumber leaves, virulence increased by 10.1, 12.9, and 10.8%, respectively. With respect to sclerotial production, carbendazim at 0.005 and 0.02 µg/ml in PDA significantly (P < 0.05) increased, while at 0.1 µg/ml significantly (P < 0.05) reduced the sclerotial number and weight of both isolates compared with nontreated controls. Conidia germination percentages slightly yet statistically significantly (P < 0.05) increased after being inoculated on PDA amended with carbendazim at 0.001 and 0.005 µg/ml. Carbendazim at 0.001∼0.02 µg/ml, either sprayed on cucumber leaves or cosuspended with conidia, exerted significantly (P < 0.05) stimulatory effects on the virulence of B. cinerea conidia. Mechanism studies showed that sublethal doses of carbendazim did not increase the expression levels of pathogenicity-related pectin methylesterase gene Bcpme1, endopolygalacturonase gene Bcpg2, cutinase gene CutA, xylanase gene Xyn11A, or NADPH oxidase gene BcnoxA.


Assuntos
Benzimidazóis , Botrytis , Carbamatos , Doenças das Plantas , Virulência , Benzimidazóis/farmacologia , Botrytis/efeitos dos fármacos , Carbamatos/farmacologia , Virulência/efeitos dos fármacos
11.
Eur J Med Chem ; 179: 483-492, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271960

RESUMO

Prostate cancer is one of the main causes of male cancer-related deaths worldwide and the suppression of androgen receptor signalling is established as an effective strategy for the treatment. A series of galeterone analogues including several steroid-fused azacycles, as well as 17-(benzimidazol-1-ylimino), 16α-(benzimidazol-2-ylamino), and 16α-(benzothiazol-2-ylamino) steroid derivatives, were synthesized and tested against prostate cancer cell lines. Candidate compound 3f was shown to reduce AR-regulated transcription in a dose-dependent manner in nanomolar ranges and suppress expression of AR-regulated proteins Nkx3.1 and PSA in 22Rv1-ARE14 and VCaP cancer cell lines. Flexible docking study revealed similar position of 3f within AR binding site in comparison of galeterone even with stronger binding energy.


Assuntos
Androstadienos/farmacologia , Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Androstadienos/síntese química , Androstadienos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Benzimidazóis/síntese química , Benzimidazóis/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Estrutura Molecular , Células PC-3 , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Relação Estrutura-Atividade
12.
Cell Physiol Biochem ; 53(1): 141-156, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31237760

RESUMO

BACKGROUND/AIMS: Previous research has indicated that the currently available histone deacetylase inhibitors (HDACis) are not effective as monotherapies against oral squamous cell carcinoma (OSCC). However, HDACis act synergistically with other therapeutic agents to exert significant antitumor activities. Thus, a strategy to develop chemotherapeutic agents by combining several active groups based on histone deacetylase (HDAC) into a single molecule as a conjugate that modulates multiple cellular pathways may be useful for the treatment of OSCC. METHODS: The novel inhibitor Roxyl-ZR was prepared by organic synthesis and its anticancer effects on OSCC were investigated by cell metabolism (n=5), colony formation (n=3), cell cycle (n=3), cell apoptosis (n=3), wound healing (n=3), transwell migration (n=3), and 5-bromo-2'-deoxyuridine staining (n=3) assays in vitro and in in vivo xenograft mice models (4 mice/group for subcutaneous xenograft and 3 mice/group for orthotopic xenograft ). The abundance of Ki67, Bcl-2, and p-STAT3 was detected by immunohistochemistry staining (n=4). Apoptotic cells in the tumor tissues of mice were detected by terminal deoxynucleotidyl transferase dUTP nickend labeling assay (n=3). The abundance of related proteins levels were evaluated by western blot (n=3). E-cadherin expression was detected by an immunofluorescence assay (n=3). RESULTS: Compared with the approved HDACi, conjugated Roxyl-ZR exhibited significantly higher antitumor effects in OSCC cells. Roxyl-ZR suppressed OSCC cell proliferation by inducing the reduction of S phase and inducing caspase-dependent apoptosis by down-regulating Bcl-2 expression. Moreover, Roxyl-ZR attenuated the epithelial-mesenchymal transition, which is closely associated with migration and invasion. In addition, Roxyl-ZR inhibited OSCC xenograft mice models and showed low toxicity. The mechanism underlying the Roxyl-ZR-enhanced sensitivity to HDACi may be attributed to the inhibition of key regulators of JAK1-STAT3 signaling pathway. CONCLUSION: HDAC-cyclin-dependent kinase conjugates represent a novel approach to the development of OSCC treatment. Our findings may open a new avenue for the development of novel inhibitors for the treatment of OSCC.


Assuntos
Apoptose/efeitos dos fármacos , Benzimidazóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Animais , Benzimidazóis/síntese química , Benzimidazóis/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Janus Quinase 1/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirimidinas/síntese química , Pirimidinas/uso terapêutico , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transplante Heterólogo
13.
Int J Mol Sci ; 20(11)2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31146414

RESUMO

AMP-activated protein kinase (AMPK) has been implicated in contractility changes in bladders with partial bladder outlet obstruction (PBOO), but the role of AMPK in the contractile response of normal bladder remains unclear. We investigated the phosphorylation of AMPKα and expression of the involved upstream AMPK kinases (AMPKKs) in a model of bladders with PBOO and sought to determine whether the pharmacological inhibition of these two factors affected detrusor contractility in normal bladders, using female Sprague-Dawley rats. Cystometry and Western blot analysis were performed in rats that were subjected to PBOO induction or a sham operation. Cystometry was performed in normal rats that received selective inhibitors of AMPKα and Ca2+/calmodulin-dependent protein kinase kinase (CaMKKß) (compound C and STO-609, respectively) at doses determined in the experiments. In the PBOO bladders, bladder weight and micturition pressure (MP) were higher and AMPKα phosphorylation (T172) and CaMKKß expression was significantly reduced. Compound C and STO-609 increased MP. The increased contractile response in bladders with PBOO-induced hypertrophy was related to decreased CaMKKß/AMPK signaling activity, and the pharmacological inhibition of this pathway in normal bladders increased detrusor contractility, implying a role of CaMKKß/AMPK signaling in the bladder in the regulation of detrusor contractility.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Contração Muscular , Proteínas Quinases/metabolismo , Obstrução do Colo da Bexiga Urinária/metabolismo , Bexiga Urinária/metabolismo , Micção , Animais , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Feminino , Naftalimidas/farmacologia , Naftalimidas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Ratos , Ratos Sprague-Dawley , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologia , Bexiga Urinária/fisiopatologia , Obstrução do Colo da Bexiga Urinária/tratamento farmacológico
14.
Nat Commun ; 10(1): 2803, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31243293

RESUMO

Enhancer elements are a key regulatory feature of many important genes. Several general features including the presence of specific histone modifications are used to demarcate potentially active enhancers. Here we reveal that putative enhancers marked with H3 lysine 79 (H3K79) di or trimethylation (me2/3) (which we name H3K79me2/3 enhancer elements or KEEs) can be found in multiple cell types. Mixed lineage leukemia gene (MLL) rearrangements (MLL-r) such as MLL-AF4 are a major cause of incurable acute lymphoblastic leukemias (ALL). Using the DOT1L inhibitor EPZ-5676 in MLL-AF4 leukemia cells, we show that H3K79me2/3 is required for maintaining chromatin accessibility, histone acetylation and transcription factor binding specifically at KEEs but not non-KEE enhancers. We go on to show that H3K79me2/3 is essential for maintaining enhancer-promoter interactions at a subset of KEEs. Together, these data implicate H3K79me2/3 as having a functional role at a subset of active enhancers in MLL-AF4 leukemia cells.


Assuntos
Elementos Facilitadores Genéticos/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Metiltransferases/metabolismo , Benzimidazóis/farmacologia , Linhagem Celular Tumoral , Estudo de Associação Genômica Ampla , Histonas/genética , Humanos , Metilação , Metiltransferases/genética
15.
Eur J Med Chem ; 179: 147-165, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31252306

RESUMO

Herein, we have carried out a structural optimization campaign to discover the novel anti-tumor agents with our previously screened YQY-26 as the hit compound. A library of thirty-seven 6-amide-2-aryl benzoxazole/benzimidazole derivatives has been designed and synthesized based on the highly conserved active site of VEGFR-2. Several title compounds exhibited selective inhibitory activities against VEGFR-2 than EGFR kinases, which also displayed selective anti-proliferation potency against the HUVEC and HepG2 than the A549 and MDA-MB-231 cancer cell lines. The newly synthesized compounds were evaluated for anti-angiogenesis capability by chick chorioallantoic membrane (CAM) assay. Among them, compounds 9d showed the most potent anti-angiogenesis ability (79% inhibition at 10 nM/eggs), the efficient cytotoxic activities (in vitro against the HUVEC and HepG2 cell lines with IC50 values of 1.47 and 2.57 µM, respectively), and excellent VEGFR-2 kinase inhibition (IC50 = 0.051 µM). The molecular docking analysis revealed that compound 9d is a Type II inhibitor of VEGFR-2 kinase. These results indicated that the 6-amide-2-arylbenzoxazole and 6-amide-2-aryl benzimidazole derivatives are promising inhibitors of VEGFR-2 kinase for the potential treatment of anti-angiogenesis.


Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Benzoxazóis/farmacologia , Desenho de Drogas , Inibidores de Proteínas Quinases/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Benzimidazóis/síntese química , Benzimidazóis/química , Benzoxazóis/síntese química , Benzoxazóis/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
16.
Molecules ; 24(11)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181622

RESUMO

Tumor suppressor p53 is mutated in about 50% of cancers. Most malignant melanomas carry wild-type p53, but p53 activity is often inhibited due to overexpression of its negative regulators Mdm2 or MdmX. We performed high throughput screening of 2448 compounds on A375 cells carrying p53 activity luciferase reporter construct to reveal compounds that promote p53 activity in melanoma. Albendazole and fenbendazole, two approved and commonly used benzimidazole anthelmintics, stimulated p53 activity and were selected for further studies. The protein levels of p53 and p21 increased upon the treatment with albendazole and fenbendazole, indicating activation of the p53-p21 pathway, while the levels of Mdm2 and MdmX decreased in melanoma and breast cancer cells overexpressing these proteins. We also observed a reduction of cell viability and changes of cellular morphology corresponding to mitotic catastrophe, i.e., G2/M cell cycle arrest of large multinucleated cells with disrupted microtubules. In summary, we established a new tool for testing the impact of small molecule compounds on the activity of p53 and used it to identify the action of benzimidazoles in melanoma cells. The drugs promoted the stability and transcriptional activity of wild-type p53 via downregulation of its negative regulators Mdm2 and MdmX in cells overexpressing these proteins. The results indicate the potential for repurposing the benzimidazole anthelmintics for the treatment of cancers overexpressing p53 negative regulators.


Assuntos
Benzimidazóis/farmacologia , Fenbendazol/farmacologia , Melanoma/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Albendazol/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Reposicionamento de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Células MCF-7 , Melanoma/tratamento farmacológico
17.
Int. j. morphol ; 37(2): 515-521, June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1002253

RESUMO

SUMMARY: Reproductive dysfunction is a complication for many diseases and toxins. Its early diagnosis and treatment are immensely important. Here the morphological histoarchitecture changes in early testicular and cauda toxicity before and after treatment with angiotensin receptor blockers were evaluated. Low-grade testicular damage was induced using thioacetamide (TAA, 50 mg/kg/day) intraperitoneally for two weeks in rats. The rats were randomly divided into four groups (n = 8) treated daily orally for three weeks as follows: Normal control (distilled water), TAA (positive control), TAA+candesartan (0.2 mg/kg) and TAA+losartan (7.5 mg/kg). Serum testosterone and testicular malondialdehyde and glutathione were measured. The changes in histoarchitecture of testis and cauda epididymis were evaluated by hematoxylin and eosin for general structure, Masson's trichrome for collagen, periodic acid Schiff for basement membrane, and caspase-3 and proliferating cell nuclear antigen (PCNA) for immunohistochemical analysis. The TAA-rats showed decreases of serum testosterone and testicular glutathione, increases in testicular malondialdehyde, degenerative changes and apoptosis in germ cells, thickening of tubular basal lamina and increases in expression of caspase 3, and decreases in expression of PCNA. The ARBs (candesartan and losartan) significantly reversed these changes with non-significant differences in-between. Treatment with ARBs (candesartan and losartan) significantly reversed TAA-induced low-grade testicular and cauda toxicity in rats. This could be potentially useful for early treatment of male patients with occupational toxicant-induced reproductive dysfunction especially if they are using ARBs for other comorbidities.


RESUMEN: La disfunción reproductiva es una complicación por muchas enfermedades y toxinas. Su diagnóstico y tratamiento tempranos son inmensamente importantes. Aquí se evaluaron los cambios morfológicos en la histoarquitectura en la toxicidad precoz testicular y cauda antes y después del tratamiento con bloqueadores de receptores de angiotensina. Se indujo daño testicular de bajo grado usando tioacetamida (TAA, 50 mg / kg / día) por vía intraperitoneal durante dos semanas en ratas. Las ratas se dividieron aleatoriamente en cuatro grupos (n = 8) tratados diariamente por vía oral durante tres semanas de la siguiente manera: control normal (agua destilada), TAA (control positivo), TAA + candesartan (0,2 mg / kg) y TAA + losartán (7,5 mg / kg). Se midieron la testosterona sérica, el malondialdehído testicular y el glutatión. Los cambios en la histoarquitectura de los testículos y la epidermis de la cauda se evaluaron mediante Hematoxilina y Eosina para determinar la estructura general, con tricrómicro de Masson para el colágeno, ácido periódico de Schiff para la membrana basal y la caspasa-3 y el antígeno nuclear de células proliferantes (PCNA) para análisis inmunohistoquímico. Las ratas TAA mostraron disminución de la testosterona sérica y glutatión testicular, aumentos en el malondialdehído testicular, cambios degenerativos y apoptosis en células germinales, engrosamiento de la lámina basal tubular y aumentos en la expresión de la caspasa 3, y disminución en la expresión de PCNA. Los ARB (candesartán y losartán) revirtieron significativamente estos cambios con diferencias no significativas en el medio. El tratamiento con BRA (candesartán y losartán) revirtió significativamente la toxicidad testicular y cauda inducida por TAA en ratas. Esto podría ser potencialmente útil para el tratamiento temprano de pacientes con disfunción reproductiva inducida por tóxicos ocupacionales, especialmente si están usando BRA para otras comorbilidades.


Assuntos
Animais , Masculino , Ratos , Testículo/efeitos dos fármacos , Tioacetamida/toxicidade , Benzimidazóis/farmacologia , Losartan/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Testículo/patologia , Testosterona/análise , Tetrazóis/farmacologia , Imuno-Histoquímica , Ratos Sprague-Dawley , Antígeno Nuclear de Célula em Proliferação/metabolismo , Caspase 3/metabolismo , Glutationa/análise , Malondialdeído/análise
18.
Cancer Sci ; 110(9): 2690-2699, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250942

RESUMO

Senescence is a state of growth arrest induced not only in normal cells but also in cancer cells by aging or stress, which triggers DNA damage. Despite growth suppression, senescent cancer cells promote tumor formation and recurrence by producing cytokines and growth factors; this state is designated as the senescence-associated secretory phenotype. In this study, we examined the susceptibility of senescent human breast cancer cells to immune cell-mediated cytotoxicity. Doxorubicin (DXR) treatment induced senescence in 2 human breast cancer cell lines, MDA-MB-231 and BT-549, with the induction of γH2AX expression and increased expression of p21 or p16. Treatment with DXR also induced the expression of senescence-associated ß-galactosidase and promoted the production of pro-inflammatory cytokines. Importantly, DXR-treated senescent MDA-MB-231 cells showed increased sensitivity to 2 types of immune cell-mediated cytotoxicity: cytotoxicity of activated CD4+ T cells and Ab-dependent cellular cytotoxicity by natural killer cells. This increased sensitivity to cytotoxicity was partially dependent on tumor necrosis factor-related apoptosis-inducing ligand and perforin, respectively. This increased sensitivity was not observed following treatment with the senescence-inducing cyclin-dependent kinase-4/6 inhibitor, abemaciclib. In addition, treatment with DXR, but not abemaciclib, decreased the expression of antiapoptotic proteins in cancer cells. These results indicated that DXR and abemaciclib induced senescence in breast cancer cells, but that they differed in their sensitivity to immune cell-mediated cytotoxicity. These findings could provide an indication for combining anticancer immunotherapy with chemotherapeutic drugs or molecular targeting drugs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linfócitos T CD4-Positivos/imunologia , Senescência Celular/imunologia , Células Matadoras Naturais/imunologia , Aminopiridinas/farmacologia , Aminopiridinas/uso terapêutico , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Proteínas Reguladoras de Apoptose/imunologia , Proteínas Reguladoras de Apoptose/metabolismo , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linhagem Celular Tumoral , Senescência Celular/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Terapia de Alvo Molecular/métodos , Recidiva Local de Neoplasia
19.
Plant Dis ; 103(8): 2076-2082, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31194616

RESUMO

Stem-end rot caused by Botryodiplodia theobromae is a destructive disease of mango. B. theobromae field isolates resistant to carbendazim (MBC) were collected in Hainan Province, China. In this study, the characteristics of these field isolates with resistance to MBC were investigated. The resistance of B. theobromae isolates to MBC was stably inherited. Both the MBC-resistant and MBC-sensitive isolates had similar mycelial growth rates, pathogenicity, sensitivity to high glucose, glycerol content, and peroxidase activity. Compared with MBC-sensitive isolates, MBC-resistant isolates were more sensitive to low temperature and had a significant decrease in sensitivity to high NaCl and a significant increase in catalase (CAT) and glutathione S-transferase (GST) activities. After MBC treatment, the cell membrane permeability of the sensitive isolates was markedly increased compared with that of the resistant isolates. Analysis of the ß-tubulin gene sequence revealed point mutations resulting in substitutions at codon 198 from glutamic acid (GAG) to alanine (GCG) in moderately resistant isolates, and at codon 200 from phenylalanine (TTC) to tyrosine (TAC) in highly resistant isolates. These ß-tubulin gene mutations were consistently associated with MBC resistance. Overall, we infer that the altered cell membrane permeability and the increase in CAT and GST activities of the resistant isolates are linked to MBC resistance.


Assuntos
Ascomicetos , Benzimidazóis , Carbamatos , Farmacorresistência Fúngica , Fungicidas Industriais , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Ascomicetos/genética , Ascomicetos/metabolismo , Benzimidazóis/farmacologia , Carbamatos/farmacologia , China , Farmacorresistência Fúngica/genética , Fungicidas Industriais/farmacologia , Genes Fúngicos/genética
20.
Anal Bioanal Chem ; 411(20): 5331-5345, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31209549

RESUMO

A novel method was developed and validated for the quantification of the three approved CDK4/6 inhibitors (abemaciclib, palbociclib, and ribociclib) in both human and mouse plasma and mouse tissue homogenates (liver, kidney, spleen, brain, and small intestine) using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). For all matrices, pretreatment was performed using 50 µL of sample by protein precipitation with acetonitrile, followed by dilution of the supernatant. Chromatographic separation of the analytes was done on a C18 column using gradient elution. A full validation was performed for human plasma, while a partial validation was executed for mouse plasma and mouse tissue homogenates. The method was linear in the calibration range from 2 to 200 ng/mL, with a correlation coefficient (r) ≥0.996 for each analyte. For both human and mouse plasma, the accuracy and precision were within ±15% and ≤15%, respectively, for all concentrations, except for the lower limit of quantification, where they were within ±20% and ≤20%, respectively. A fit-for-purpose strategy was followed for tissue homogenates, and the accuracy and precision were within ±20% and ≤20%, respectively, for all concentrations. Stability of all analytes in all matrices at different processing and storage conditions was tested; ribociclib and palbociclib were unstable in most tissue homogenates and conditions were modified to increase the stability. The method was successfully applied for the analysis of mouse samples from preclinical studies. A new ribociclib metabolite was detected in mouse plasma samples with the same m/z transition as the parent drug.


Assuntos
Aminopiridinas/análise , Benzimidazóis/análise , Cromatografia Líquida/métodos , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Piperazinas/análise , Inibidores de Proteínas Quinases/análise , Purinas/análise , Piridinas/análise , Espectrometria de Massas em Tandem/métodos , Aminopiridinas/farmacologia , Animais , Benzimidazóis/farmacologia , Humanos , Camundongos , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Piridinas/farmacologia
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