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1.
Acta Pharmacol Sin ; 44(6): 1122-1134, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36627343

RESUMO

Aggregation of α-synuclein, a component of Lewy bodies (LBs) or Lewy neurites in Parkinson's disease (PD), is strongly linked with disease development, making it an attractive therapeutic target. Inhibiting aggregation can slow or prevent the neurodegenerative process. However, the bottleneck towards achieving this goal is the lack of such inhibitors. In the current study, we established a high-throughput screening platform to identify candidate compounds for preventing the aggregation of α-synuclein among the natural products in our in-house compound library. We found that a small molecule, 03A10, i.e., (+)-desdimethylpinoresinol, which is present in the fruits of Vernicia fordii (Euphorbiaceae), modulated aggregated α-synuclein, but not monomeric α-synuclein, to prevent further elongation of α-synuclein fibrils. In α-synuclein-overexpressing cell lines, 03A10 (10 µM) efficiently prevented α-synuclein aggregation and markedly ameliorated the cellular toxicity of α-synuclein fibril seeds. In the MPTP/probenecid (MPTP/p) mouse model, oral administration of 03A10 (0.3 mg· kg-1 ·d-1, 1 mg ·kg-1 ·d-1, for 35 days) significantly alleviated behavioral deficits, tyrosine hydroxylase (TH) neuron degeneration and p-α-synuclein aggregation in the substantia nigra (SN). As the Braak hypothesis postulates that the prevailing site of early PD pathology is the gastrointestinal tract, we inoculated α-synuclein preformed fibrils (PFFs) into the mouse colon. We demonstrated that α-synuclein PFF inoculation promoted α-synuclein pathology and neuroinflammation in the gut and brain; oral administration of 03A10 (5 mg· kg-1 ·d-1, for 4 months) significantly attenuated olfactory deficits, α-synuclein accumulation and neuroinflammation in the olfactory bulb and SN. We conclude that 03A10 might be a promising drug candidate for the treatment of PD. 03A10 might be a novel drug candidate for PD treatment, as it inhibits α-synuclein aggregation by modulating aggregated α-synuclein rather than monomeric α-synuclein to prevent further elongation of α-synuclein fibrils and prevent α-synuclein toxicity in vitro, in an MPTP/p mouse model, and PFF-inoculated mice.


Assuntos
Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Doenças Neuroinflamatórias , Substância Negra/metabolismo , Substância Negra/patologia , Encéfalo/metabolismo
2.
Acta Pharmacol Sin ; 43(8): 2147-2155, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34907358

RESUMO

Dipeptidyl peptidase-4 (DPP4) plays a crucial role in regulating the bioactivity of glucagon-like peptide-1 (GLP-1) that enhances insulin secretion and pancreatic ß-cell proliferation, making it a therapeutic target for type 2 diabetes. Although the crystal structure of DPP4 has been determined, its structure-function mechanism is largely unknown. Here, we examined the biochemical properties of sporadic human DPP4 mutations distal from its catalytic site, among which V486M ablates DPP4 dimerization and causes loss of enzymatic activity. Unbiased molecular dynamics simulations revealed that the distal V486M mutation induces a local conformational collapse in a ß-propeller loop (residues 234-260, defined as the flap) and disrupts the dimerization of DPP4. The "open/closed" conformational transitions of the flap whereby capping the active site, are involved in the enzymatic activity of DPP4. Further site-directed mutagenesis guided by theoretical predictions verified the importance of the conformational dynamics of the flap for the enzymatic activity of DPP4. Therefore, the current studies that combined theoretical modeling and experimental identification, provide important insights into the biological function of DPP4 and allow for the evaluation of directed DPP4 genetic mutations before initiating clinical applications and drug development.


Assuntos
Diabetes Mellitus Tipo 2 , Dipeptidil Peptidase 4 , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/genética , Peptídeo 1 Semelhante ao Glucagon , Humanos , Mutação
3.
Chin Med Sci J ; 36(1): 27-34, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33853706

RESUMO

Objective To characterize Chinese families in which both parents and at least one child are diagnosed with malignant diseases and provide reference for cancer screening or early detection in people whose both parents are diagnosed with cancer. Methods Medical records of all clients to the center of cancer screening and prevention of the National Cancer Center/Cancer Hospital between January 2008 and February 2018 were screened to select families in which both parents and at least one child were diagnosed with malignant diseases. The cancer profiles of fathers, mothers, sons and daughters, their age distribution at diagnosis, and similarity of cancers between two generations were analyzed. The proportions of each cancer in males and females of the cohort were compared with corresponding data from the National Cancer Center Registry of China (NCCRC) in 2013. Results Totally 135 families were identified from records of 33 200 clients. Proportion of lung cancer in fathers (40/135, 29.6%) and in mothers (38/135, 28.1%) were higher than the national data (23.9% in males and 14.9% in females, respectively). The proportion of breast cancer in daughters (35/109, 32.1%) was higher than that of mothers (14/135, 10.4%) and the national data (17.1%). In 71 father-son pairs of cancer, 46.5% (33/71) were of the same systematic disease, and 16.9% (12/71) were of the same cancer. These two indexes were 31.2% (n=34) and 10.1% (n=11), respectively in the 109 father-daughter pairs of cancer, 36.6% (n=26) and 8.5% (n=6) respectively in the 71 mother-son pairs of cancer, and 31.2% (n=34) and 20.2% (n=20) respectively in the 109 mother-daughter pairs of cancer. Sons were more likely to suffer from cancers originated from the same system as father's cancer than daughters (χ 2=4.299, P<0.05), and daughters were more likely to suffer from the same cancer as their mother's cancer than sons (χ 2=4.506, P<0.05). The age (mean ± standard deviation) of the daughters (52.4±12.7) and the sons (59.4±10.9) at diagnosis were significantly younger than the fathers (65.5±12.2) and the mothers (65.7 ±12.5) (all P<0.001). Conclusions For people whose both parents are diagnosed as cancer, screening or early detection examinations should cover a full range of cancers rather than the cancers their father and mother have suffered, or cancers stemmed from the same system as their parent's cancers. We suggest screening or early detection program for these special population start earlier than that for the general population, with emphasis on cancers derived from digestive system for males and women-specific cancers, i.e., breast cancer, ovarian cancer, cervical cancer and uterine cancer for females.


Assuntos
Neoplasias , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Mães , Neoplasias/epidemiologia , Neoplasias/genética , Pais , Estudos Retrospectivos
4.
Acta Pharmacol Sin ; 38(7): 1059-1068, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28414204

RESUMO

The mutation of B-RafV600E is widespread in a variety of human cancers. Its inhibitors vemurafenib and dabrafenib have been launched as drugs for treating unresectable melanoma, demonstrating that B-RafV600E is an ideal drug target. This study focused on developing novel B-RafV600E inhibitors as drug leads against various cancers with B-RafV600E mutation. Using molecular modeling approaches, 200 blockbuster drugs were spliced to generate 283 fragments followed by molecular docking to identify potent fragments. Molecular structures of potential inhibitors of B-RafV600E were then obtained by fragment reassembly followed by docking to predict the bioactivity of the reassembled molecules. The structures with high predicted bioactivity were synthesized, followed by in vitro study to identify potent B-RafV600E inhibitors. A highly potent fragment binding to the hinge area of B-RafV600E was identified via a docking-based structural splicing approach. Using the fragment, 14 novel structures were designed by structural reassembly, two of which were predicted to be as strong as marketed B-RafV600E inhibitors. Biological evaluation revealed that compound 1m is a potent B-RafV600E inhibitor with an IC50 value of 0.05 µmol/L, which was lower than that of vemurafenib (0.13 µmol/L). Moreover, the selectivity of 1m against B-RafWT was enhanced compared with vemurafenib. In addition, 1m exhibits desirable solubility, bioavailability and metabolic stability in in vitro assays. Thus, a highly potent and selective B-RafV600E inhibitor was designed via a docking-based structural splicing and reassembly strategy and was validated by medicinal synthesis and biological evaluation.


Assuntos
Antineoplásicos/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Purinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/síntese química , Imidazóis/química , Imidazóis/farmacologia , Indóis/síntese química , Indóis/química , Indóis/farmacologia , Estrutura Molecular , Oximas/síntese química , Oximas/química , Oximas/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Purinas/síntese química , Purinas/química , Solubilidade , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/farmacologia , Vemurafenib
5.
Zhong Yao Cai ; 39(1): 11-5, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-30079697

RESUMO

Objective: In order to provide the theoretical basis for the Guangfeng medicinal yam( Dioscorea opposita) in field transplanting, the effect of PEG-6000 simulation drought stress on physiological characteristics of Guangfeng medicinal yam plantlets was studied. Methods: Using the method of spectrophotometer,the content of total chlorophyll,soluble total sugar, soluble protein and praline,as well as the activities of SOD,CAT and POD of Guangfeng medicinal yam plantlets were tested under PEG-6000 treatment. Results: Under PEG-6000 simulated drought stress, with the increasing of drought stress and the extension of stress time, the total chlorophyll content of Guangfeng medicinal yam plantlets continued to decline, the content of total soluble sugar, proline and MDA of Guangfeng medicinal yam plantlets significantly increased, the content of soluble protein and the activities of CAT,POD and SOD of Guangfeng medicinal yam plantlets increased at first and then decreased. Conclusion: This study reveals the changes of physiological indices of Guangfeng medicinal yam plantlets under PEG-6000 simulation drought stress, which indicated that Guangfeng medicinal yam plantlets have certain drought tolerance.


Assuntos
Dioscorea , Secas , Clorofila , Polietilenoglicóis , Prolina , Estresse Fisiológico
6.
Zhong Yao Cai ; 39(7): 1446-51, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30199614

RESUMO

Objective: To study the rapid propagation in vitro of Dioscorea opposita'Guangfeng', and to observe the stomas of the transplanting plantlets and potted seedlings, to test chromosome ploidy by FCM, and to detect DNA mutation by ISSR,in order to provide the technical basis for the large-scale production of Dioscorea opposita 'Guangfeng' plantlets. Methods: The technique system of Dioscorea opposita 'Guangfeng'rapid propagation in vitro was established and optimized by plant tissue culture method. The parameters of transplanting plantlets and potted seedlings were studied as follows, the stomatal parameters were observed by transparent adhesive tape method, chromosome ploidy were analyzed by FCM, and DNA mutation were detected by ISSR molecular marker. Results: The technique system of Dioscorea opposite 'Guangfeng' rapid propagation in vitro was as follows, slightly woody stem segment with a bud were selected and inoculated onto MS + KT 1 mg / L + NAA 0. 2 mg / L solid culture medium and cultured in the photoperiod of 14 h / d( the temperature was( 25 ± 2) ℃ and light intensity was 1 500 ~ 2 000 Lx) after disinfected for 1 min in 70% alcohol prior to sterilized for 12 min with 0. 1% Hg Cl2,the materials were washed with sterile water for 3 times, respectively. The new bud was cut off when it grew to 2 ~ 3cm and inoculated into MS + KT 2 mg / L + NAA 0. 5 mg / L liquid culture medium and continued to culture in above culture conditions. The whole plant was formed after cultured for about 90 d. The sealing membrane was opened in transplanting, and the plantlets was still placed in above culture conditions and cultured for 2 ~ 3 d, and then the whole plant was taken out, and the culture medium washed off and then transferred into the vessel with shallow liquid MS basic culture medium and domesticated indoor. The acclimated plantlets were taken out and transplanted in the outdoor pots with the sandy soil when the new shoots grew out, and watered one time with tap water in the morning and evening per day, the survival rate reached 100%. The results of stomatal observation, FCM analysis and ISSR detection of transplanting plantlets and potted seedlings showed that the stomatal parameters, chromosome ploidy and DNA mutation of plantlets and potted seedlings had no variation. Conclusion: The results reveal that the establishment and optimization of the technique system of Dioscorea opposita 'Guangfeng' rapid propagation in vitro is feasible, and the regenerated plants do not have genetic variation which can ensure the stability of the genetic.


Assuntos
Cromossomos de Plantas , Dioscorea , Ploidias , Meios de Cultura , DNA , Variação Genética , Mutação , Reguladores de Crescimento de Plantas , Regeneração , Plântula , Técnicas de Cultura de Tecidos
7.
Phytother Res ; 29(7): 1040-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25826437

RESUMO

(2'R)-2',3'-Dihydro-2'-(1-hydroxy-1-methylethyl)-2,6'-bibenzofuran-6,4'-diol (DHMB) is a natural compound extracted from Morus notabilis. It was found that DHMB acts as a competitive inhibitor against mushroom tyrosinase with a Ki value of 14.77 µM. Docking results further indicated that it could form strong interactions with one copper ion with a distance of 2.7 Å, suggesting the mechanism of inhibition might be due to chelating copper ions in the active site. Furthermore, melanin production in B16-F10 murine melanoma cells was significantly inhibited by DHMB in a concentration-dependent manner without cytotoxicity. The results of western blotting also showed that DHMB decreased 3-isobuty-1-methxlzanthine-induced mature tyrosinase expression. Taken together, these findings indicated that DHMB may be a new promising pigmentation-altering agent for agriculture, cosmetic, and therapeutic applications.


Assuntos
Agaricales/enzimologia , Benzofuranos/química , Melaninas/biossíntese , Melanoma Experimental/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Inibidores Enzimáticos/química , Camundongos , Simulação de Acoplamento Molecular , Morus/química
8.
Zhong Yao Cai ; 38(11): 2245-9, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-27356371

RESUMO

OBJECTIVE: In order to provide methodology reference for virus-free and germplasm conservation of Guangfeng medicinal yam (Dioscorea opposita) plantlets, rapid micropropagation in vitro technique of Guangfeng medicinal yam plantlets was studied. METHODS: Using the method of plant tissue culture, single factor test and flow-cytometry, the basic procedure of Guangfeng medicinal yam tissue culture was established and the DNA content of Guangfeng medicinal yam plantlets and its potted seedlings was detected. RESULTS: The best disinfection procedure of stems with a bud of Guangfeng medicinal yam was washed with sterile water for three times after sterilized with 70% alcohol for 20 - 30 s and then washed with sterile water for three times again after sterilized with 0.1% mercuric chloride for 10 - 12 min; The best explants of stems with a bud of Guangfeng medicinal yam was slightly woody and more mature stems witha bud; The best proliferation culture medium of stems with a bud of Guangfeng medicinal yam was MS + 6-BA 2.0 mg/L + NAA 0.1 mg/L; The best rooting culture medium of stems with a bud of Guangfeng medicinal yam was MS + NAA 0.5 mg/L; The best culture method of Guangfeng medicinal yam plantlets was liquid culture; The best transplanting matrix of Guangfeng medicinal yam plantlets was the mixture of paddy clay and fine sand (1: 2) or the mixture of perlite and vermiculite (1: 2); The DNA content between Guangfeng medicinal yam plantlets and its potted seedlings had no significant difference. CONCLUSION: A fast and efficient micropropagation in vitro technological system of stems with a bud of Guangfeng medicinal yam is established, and the flow cytometry detect results also show the genetic stability of Guangfeng medicinal yam plantlets, whose results provide the technical and theoretical basis for the large-scale production of Guangfeng medicinal yam plantlets.


Assuntos
Técnicas de Cultura , Dioscorea/crescimento & desenvolvimento , Plantas Medicinais/crescimento & desenvolvimento , Meios de Cultura , DNA de Plantas/isolamento & purificação , Plântula/crescimento & desenvolvimento
9.
Acta Pharmacol Sin ; 35(3): 419-31, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24487966

RESUMO

AIM: To develop a reliable computational approach for predicting potential drug targets based merely on protein sequence. METHODS: With drug target and non-target datasets prepared and 3 classification algorithms (Support Vector Machine, Neural Network and Decision Tree), a multi-algorithm and multi-model based strategy was employed for constructing models to predict potential drug targets. RESULTS: Twenty one prediction models for each of the 3 algorithms were successfully developed. Our evaluation results showed that ∼30% of human proteins were potential drug targets, and ∼40% of putative targets for the drugs undergoing phase II clinical trials were probably non-targets. A public web server named D3TPredictor (http://www.d3pharma.com/d3tpredictor) was constructed to provide easy access. CONCLUSION: Reliable and robust drug target prediction based on protein sequences is achieved using the multi-algorithm and multi-model strategy.


Assuntos
Algoritmos , Desenho Assistido por Computador , Bases de Dados de Proteínas , Descoberta de Drogas/métodos , Internet , Proteoma , Sequência de Aminoácidos , Árvores de Decisões , Humanos , Redes Neurais de Computação , Reprodutibilidade dos Testes , Relação Estrutura-Atividade , Máquina de Vetores de Suporte
10.
Yao Xue Xue Bao ; 49(10): 1433-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25577874

RESUMO

Two new sulfated sesquiterpenoids, megastigman-7-ene-3, 5, 6, 9-tetrol-3-O-ß-D-6'-sulfonated-glucopyranoside (1) and 3-O-ß-D-6'-sulfonated-glucopyranosyl-6-(3-oxo-2-butenylidenyl)-1, 1, 5-trimethylcyclohexan-5-ol (2), along with one known sesquitepenoid compound icariside B1 (3) were isolated from the whole herb of Petasites tricholobus Franch. Their structures were identified by their chemical and spectroscopic characters. All obtained compounds were tested for their cytotoxicity against four cancer cell lines.


Assuntos
Petasites/química , Sesquiterpenos/farmacologia , Linhagem Celular Tumoral , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Humanos , Norisoprenoides/isolamento & purificação , Norisoprenoides/farmacologia , Sesquiterpenos/isolamento & purificação
11.
Chin J Cancer ; 32(8): 453-60, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23863562

RESUMO

Nasopharyngeal carcinoma (NPC) is rare globally but common in China and exhibits a distinct ethnic and geographic distribution. In 2009, the National Central Cancer Registry in China provided real-time surveillance information on NPC. Individual NPC cases were retrieved from the national database based on the ICD-10 topography code C11. The crude incidence and mortality of NPC were calculated by sex and location (urban/rural). China's population in 1982 and Segi's world population structures were used to determine age-standardized rates. In regions covered by the cancer registries in 2009, the crude incidence of NPC was 3.61/100,000 (5.08/100,000 in males and 2.10/100,000 in females; 4.19/100,000 in urban areas and 2.42/100,000 in rural areas). Age-standardized incidences by Chinese population (ASIC) and Segi's world population (ASIW) were 2.05/100,000 and 2.54/100,000, respectively. The crude mortality of NPC was 1.99/100,000 (2.82/100,000 in males and 1.14/100,000 in females; 2.30/100,000 in urban areas and 1.37/100,000 in rural areas). The age-standardized mortalities by Chinese population (ASMC) and world population (ASMW) were 1.04/100,000 and 1.35/100,000, respectively. The incidence and mortality of NPC were higher in males than in females and higher in urban areas than in rural areas. Both age-specific incidence and mortality were relatively low in persons younger than 30 years old, but these rates dramatically increased. Incidence peaked in the 60-64 age group and mortality peaked in the over 85 age group. Primary and secondary prevention, such as lifestyle changes and early detection, should be carried out in males and females older than 30 years of age.


Assuntos
Neoplasias Nasofaríngeas/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Sistema de Registros , População Rural , Fatores Sexuais , População Urbana , Adulto Jovem
12.
Neuro Endocrinol Lett ; 44(6): 410-417, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37776558

RESUMO

BACKGROUND: Cranionasal communicating tumors often originate from the extra-axial intracranial tissue, nasal cavity, and sinuses, and mostly invade the anterior skull base, leading to communication between the cranial and nasal cavities. Cranionasal communicating tumors are clinically rare and thus have been rarely reported in the literature. OBJECTIVE: To investigate the clinical outcomes of combined transcranial and endoscopic transnasal approaches in the surgical management of cranionasal communicating tumors. METHODS: We retrospectively analyzed patients with cranionasal communicating tumors treated at the Department of Neurosurgery, Jinhua Hospital, affiliated with Zhejiang University, from July 2017 to March 2020. All patients were surgically treated using combined transcranial and endoscopic transnasal approaches or the cranionasal dual approach, and skull base reconstruction was performed simultaneously. The postoperative gross tumor resection rate, perioperative complications, and postoperative efficacy were evaluated. RESULTS: Eleven patients with 14-37 months of follow-up were included. Eight patients underwent total resection, two patients underwent subtotal resection, and one patient was treated with partial resection. Postoperative pathological diagnoses revealed four olfactory neuroblastomas, three atypical meningiomas, two recurrent papilloma malignancies, one recurrent invasive pituitary tumor, and one recurrent invasive pituitary adenocarcinoma. Among the 11 patients, severe cerebral edema was observed postoperatively in one patient, and decompression craniectomy was performed. Intracranial infection was observed in two patients, including one with transient cerebrospinal fluid leakage, which was cured after symptomatic treatment. Moreover, postoperative ocular dysmotility and worse olfactory sensation were observed in one and two patients, respectively. The mean follow-up time of the 11 patients was (24.4 ± 5.7) months. The one-year survival rate of the patients was 100%; 10 patients (90.9%) had a favorable outcome (Glasgow Outcome Scale score of 4-5), and only one patient (9.1%) had a Glasgow Outcome Scale score of 3. Furthermore, during the last follow-up, tumor recurrence occurred in two patients (18.2%). CONCLUSION: Surgical treatment of cranionasal communicating tumors using the cranionasal dual approach and simultaneous skull base reconstruction improves the gross tumor resection rate with fewer postoperative complications and good short-term efficacy.


Assuntos
Adenocarcinoma , Neoplasias Nasais , Neoplasias da Base do Crânio , Humanos , Estudos Retrospectivos , Recidiva Local de Neoplasia , Endoscopia , Base do Crânio/patologia , Base do Crânio/cirurgia , Neoplasias da Base do Crânio/cirurgia , Neoplasias Nasais/cirurgia , Resultado do Tratamento
13.
Acta Pharmacol Sin ; 33(8): 1062-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22728712

RESUMO

AIM: To explore the function of the conserved aromatic cluster F213(5.47), F308(6.51), and F309(6.52) in human ß3 adrenergic receptor (hß3AR). METHODS: Point mutation technology was used to produce plasmid mutations of hß3AR. HEK-293 cells were transiently co-transfected with the hß3AR (wild-type or mutant) plasmids and luciferase reporter vector pCRE-luc. The expression levels of hß3AR in the cells were determined by Western blot analysis. The constitutive signalling and the signalling induced by the ß3AR selective agonist, BRL (BRL37344), were then evaluated. To further explore the interaction mechanism between BRL and ß3AR, a three-dimensional complex model of ß3AR and BRL was constructed by homology modelling and molecular docking. RESULTS: For F308(6.51), Ala and Leu substitution significantly decreased the constitutive activities of ß3AR to approximately 10% of that for the wild-type receptor. However, both the potency and maximal efficacy were unchanged by Ala substitution. In the F308(6.51)L construct, the EC(50) value manifested as a "right shift" of approximately two orders of magnitude with an increased E(max). Impressively, the molecular pharmacological phenotype was similar to the wild-type receptor for the introduction of Tyr at position 308(6.51), though the EC(50) value increased by approximately five-fold for the mutant. For F309(6.52), the constitutive signalling for both F309(6.52)A and F309(6.52)L constructs were strongly impaired. In the F309(6.52)A construct, BRL-stimulated signalling showed a normal E(max) but reduced potency. Leu substitution of F309(6.52) reduced both the E(max) and potency. When F309(6.52) was mutated to Tyr, the constitutive activity was decreased approximately three-fold, and BRL-stimulated signalling was significantly impaired. Furthermore, the double mutant (F308(6.51)A_F309(6.52)A) caused the total loss of ß3AR function. The predicted binding mode between ß3AR and BRL revealed that both F308(6.51) and F309(6.52) were in the BRL binding pocket of ß3AR, while F213(5.47) and W305(6.48) were distant from the binding site. CONCLUSION: These results revealed that aromatic residues, especially F308(6.51) and F309(6.52), play essential roles in the function of ß3AR. Aromatic residues maintained the receptor in a partially activated state and significantly contributed to ligand binding. The results supported the common hypothesis that the aromatic cluster F[Y]5.47/F[Y]6.52/F[Y]6.51 conserved in class A G protein-coupled receptor (GPCR) plays an important role in the structural stability and activation of GPCRs.


Assuntos
Receptores Adrenérgicos beta 3/química , Receptores Adrenérgicos beta 3/metabolismo , Animais , Sítios de Ligação/fisiologia , Células CHO , Análise por Conglomerados , Cricetinae , Cricetulus , Células HEK293 , Humanos , Estrutura Secundária de Proteína
14.
Yao Xue Xue Bao ; 47(12): 1567-74, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23460959

RESUMO

BRAF is one of the most important pro-oncogenes, which is mutated in approximately 8% of human tumors. The most common BRAF mutation is a valine-to-glutamate transition (V600E) that is expressed primarily in melanoma, colorectal cancer and thyroid carcinoma. MEK/ERK is constitutively activated in the cells expressing BRAFV600E, leading to tumor development, invasion, and metastasis. Therefore, BRAFV600E is a therapeutic target for melanoma and some other BRAFV600E tumors. Vemurafenib, a BRAFV600E inhibitor, which was approved by FDA for the treatment of late-stage melanoma in 2011, produces improved rates of overall and progression-free survival in patients with the BRAFV600E mutation, making a dramatic breakthrough in melanoma treatment. Vemurafenib is also an individual target drug based on genetic diagnosis. However, its therapeutic success is limited by the emergence of drug resistance. Therefore, it is important to explore the mechanisms underlying the resistance for developing new inhibitor drugs and for preventing or delaying the resistance evolution to BRAF inhibitor drugs. In this review, we described the role of BRAFV600E as an anti-tumor drug target and the development of BRAF inhibitors. We also discussed the mechanisms leading to resistance of BRAFV600E inhibitors. Furthermore, therapeutic strategies that might be employed to overcome acquired resistance were proposed.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Indóis/uso terapêutico , Melanoma , Mutação , Proteínas Proto-Oncogênicas B-raf , Sulfonamidas/uso terapêutico , Animais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Sistemas de Liberação de Medicamentos , Humanos , Imidazóis/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Oximas/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Vemurafenib
15.
Acta Pharmacol Sin ; 32(11): 1424-30, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21963891

RESUMO

AIM: To construct a reliable computational model for the classification of agonists and antagonists of 5-HT(1A) receptor. METHODS: Support vector machine (SVM), a well-known machine learning method, was employed to build a prediction model, and genetic algorithm (GA) was used to select the most relevant descriptors and to optimize two important parameters, C and r of the SVM model. The overall dataset used in this study comprised 284 ligands of the 5-HT(1A) receptor with diverse structures reported in the literatures. RESULTS: A SVM model was successfully developed that could be used to predict the probability of a ligand being an agonist or antagonist of the 5-HT(1A) receptor. The predictive accuracy for training and test sets was 0.942 and 0.865, respectively. For compounds with probability estimate higher than 0.7, the predictive accuracy of the model for training and test sets was 0.954 and 0.927, respectively. To further validate our model, the receiver operating characteristic (ROC) curve was plotted, and the Area-Under-the-ROC- Curve (AUC) value was calculated to be 0.883 for training set and 0.906 for test set. CONCLUSION: A reliable SVM model was successfully developed that could effectively distinguish agonists and antagonists among the ligands of the 5-HT(1A) receptor. To our knowledge, this is the first effort for the classification of 5-HT(1A) receptor agonists and antagonists based on a diverse dataset. This method may be used to classify the ligands of other members of the GPCR family.


Assuntos
Inteligência Artificial , Desenho de Fármacos , Receptor 5-HT1A de Serotonina/metabolismo , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Humanos , Modelos Biológicos
16.
Asian Pac J Cancer Prev ; 16(9): 3945-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25987066

RESUMO

BACKGROUND: For brachytherapy of cervical cancer, applicator shifts can not be avoided. The present investigation concerned Utrecht interstitial applicator shifts and their effects on organ movement and DVH parameters during 3D CT-based HDR brachytherapy of cervical cancer. MATERIALS AND METHODS: After the applicator being implanted, CT imaging was achieved for oncologist contouring CTVhr, CTVir, and OAR, including bladder, rectum, sigmoid colon and small intestines. After the treatment, CT imaging was repeated to determine applicator shifts and OARs movements. Two CT images were matched by pelvic structures. In both imaging results, we defined the tandem by the tip and the base as the marker point, and evaluated applicator shift, including X, Y and Z. Based on the repeated CT imaging, oncologist contoured the target volume and OARs again. We combined the treatment plan with the repeated CT imaging and evaluated the change range for the doses of CTVhr D90, D2cc of OARs. RESULTS: The average applicator shift was -0.16 mm to 0.10 mm for X, 1.49 mm to 2.14 mm for Y, and 1.9 mm to 2.3 mm for Z. The change of average physical doses and EQD2 values in Gyα/ß range for CTVhr D90 decreased by 2.55 % and 3.5 %, bladder D2cc decreased by 5.94 % and 8.77 %, rectum D2cc decreased by 2.94 % and 4 %, sigmoid colon D2cc decreased by 3.38 % and 3.72 %, and small intestines D2cc increased by 3.72 % and 10.94 %. CONCLUSIONS: Applicator shifts and DVH parameter changes induced the total dose inaccurately and could not be ignored. The doses of target volume and OARs varied inevitably.


Assuntos
Braquiterapia/instrumentação , Carcinoma de Células Escamosas/radioterapia , Imageamento Tridimensional/métodos , Radioterapia Guiada por Imagem , Tomografia Computadorizada por Raios X/métodos , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Braquiterapia/métodos , Carcinoma de Células Escamosas/patologia , Colo Sigmoide/efeitos da radiação , Feminino , Humanos , Pessoa de Meia-Idade , Órgãos em Risco , Prognóstico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Bexiga Urinária/efeitos da radiação , Neoplasias do Colo do Útero/patologia
17.
Asian Pac J Cancer Prev ; 14(11): 6501-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24377557

RESUMO

To obtain a screening and early detection reference for individuals who have a family history of cancer on the paternal side, we collected and analyzed data from 240 pairs in which both fathers and their children were diagnosed with cancer. Disease categories of fathers and sons were similar to that of the general population of China, whereas daughters were different from general female population with high incidence of breast cancer and gynecological cancer. Sons were more likely than daughters to have the same type of cancer, or to have cancer in the same organ system as their fathers (P <0.0001). Sons and daughters developed malignant diseases 11 and 16 years earlier than their fathers, respectively (P < 0.0001 for both sons and daughters). Daughters developed malignant diseases 5 years earlier than sons (P < 0.0001). Men with a family history of malignant tumors on the paternal side should be screened for malignancies from the age of 45 years, or 11 years earlier than the age of their fathers< diagnosis, and women should be screened from the age of 40 years, or 16 years earlier than the age at which their fathers were diagnosed with cancer. Lung cancer should be investigated in both men and women, whilst screening should focus on cancer of the digestive system in men and on breast and gynecological cancer (ovary, uterine and cervical cancer) in women.


Assuntos
Pai/estatística & dados numéricos , Neoplasias/epidemiologia , Núcleo Familiar , Idoso , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores de Tempo
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 25(4): 351-3, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19351510

RESUMO

AIM: To study the mechanism of cinobufacin-induced apoptosis in BIU87 cell. METHODS: Growth inhibition of bladder cancer cells in vitro were estimated using MTT assay. Apoptotic cells were detected by in-situ cell apoptosis detection kit, and confirmed by flow cytometry. The mRNA level affected by cinobufacin was determined with RT-PCR. Caspase-3 activity was estimated with chromometry. RESULTS: Cinobufacin inhibited the proliferation of BIU87 cells and induced apoptosis. More than 50% cells were killed with 0.2 mg/L of cinobufacin for 72 h. S-phase and G2-phase arrest was induced. There were significant changes of Bcl-2, caspase-3 mRNA and caspase-3 activity; while no changes of bax was found. CONCLUSION: Cinobufacin can inhibit the proliferation of BIU87 cells by inducting apoptosis, which may be related with S- and G2-phase arrest, down-regulation of Bcl-2, and increasing caspase-3 expression and its activity.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Fase G2/efeitos dos fármacos , Concentração Inibidora 50 , Microscopia de Fluorescência , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fase S/efeitos dos fármacos , Fatores de Tempo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
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