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1.
Front Allergy ; 5: 1345929, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774588

RESUMEN

Background: Oral immunotherapy (OIT) is a promising allergen-specific approach in the management of food allergy; however, studies on OIT for allergic rhinitis (AR) have rarely been reported. The purpose of this study is to evaluate the efficacy and safety of OIT using enteric-coated capsules for AR induced by house dust mites. Methods: A total of 49 patients with AR were enrolled, including 25 who received subcutaneous immunotherapy (SCIT) and 24 who received OIT. The clinical efficacy and safety in both groups were evaluated. Results: After 1 year of treatment, both SCIT and OIT demonstrated significant therapeutic effects. OIT was found to be more effective than SCIT in reducing the total AR symptom score and improving the results of nasal provocation tests. Local and systemic adverse reactions were observed in the SCIT group, while none were reported in the OIT group. Conclusion: OIT is an effective and safe treatment for mite-induced AR.

2.
J Oral Maxillofac Surg ; 72(6): 1106-18, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24629698

RESUMEN

PURPOSE: The present study examined the correlation of α-dystroglycan (α-DG) expression and like-acetylglucosaminyl transferase (LARGE) with metastasis of human tongue cancer. MATERIALS AND METHODS: Fifty human tongue cancer tissues and 2 tongue squamous cell carcinoma cell lines (CAL27 and SCC4) were involved. Immunohistochemistry was used to detect the expression of α-DG and LARGE. Methylation-specific polymerase chain reaction was performed to assess the methylation status of the LARGE gene promoter. CAL27 and SCC4 cells were transfected with exogenous LARGE and treated with 5-aza-2'-deoxycytidine (Aza-dC), respectively. Glycol sites of α-DG were detected by western blotting. In addition, the laminin overlay assay, cell adhesion assay, and invasion assay were performed. RESULTS: Immunohistochemical results showed that decreased expression of VIA4-1 and IIH6 (antibodies that recognize the glycol sites of α-DG) were correlated with the lymph node metastasis of tongue cancer (n = 50; P = .016 and .025, respectively). Decreased LARGE expression and hypermethylation of the LARGE gene promoter were correlated with lymph node metastasis and α-DG glycosylation in human tongue cancer (n = 50; P = .043 and .015 respectively). In addition, LARGE overexpression and Aza-dC treatment actively led to restoration of functional α-DG expression, elevation of laminin binding, and decrease of migratory ability in cancer cells. CONCLUSION: The results suggested that absent α-DG expression and LARGE deregulation were closely associated with nodal metastasis of tongue cancer. Aberrant α-DG expression and glycosylation were attributed at least in part to the abnormal epigenetic modification of LARGE, especially the hypermethylation of its promoter.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Distroglicanos/análisis , N-Acetilglucosaminiltransferasas/análisis , Neoplasias de la Lengua/patología , Azacitidina/análogos & derivados , Azacitidina/farmacología , Carcinoma de Células Escamosas/patología , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Metilación de ADN , Metilasas de Modificación del ADN/antagonistas & inhibidores , Decitabina , Distroglicanos/genética , Inhibidores Enzimáticos/farmacología , Epigénesis Genética/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Glicosilación , Humanos , Inmunohistoquímica , Laminina/análisis , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , N-Acetilglucosaminiltransferasas/genética , Invasividad Neoplásica , Estadificación de Neoplasias , Plásmidos/genética , Regiones Promotoras Genéticas/genética , Transfección
3.
Cancer Biol Ther ; 15(3): 342-9, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24351553

RESUMEN

High endothelial venules (HEVs) are special blood vessels in the paracortical region of lymph nodes (LNs) and govern lymphocyte recruitment. LN metastasis has similarity to circulating lymphocytes homing to LNs, but the role of HEVs in the progression of oral and pharyngeal squamous cell carcinoma (OPSCC) is unclear. In this study, we found that HEVs experienced a series of morphological and functional changes during OPSCC progression and were correlated with LN metastasis. In 9 cases of 73 metastatic LNs, tumor emboli were located adjacent to HEVs or just out of the vessels but not lymphatic channels. Gap junctions of tumor cells close to HEVs decreased or disappeared, and gaps were left at contact points where tumor cells attached to the HEVs. Moreover, the proliferation rate of endothelial cells of HEVs was the highest in metastatic LNs. Finally, L-selectin was detected in both primary and metastatic tumors, and it facilitated tumor cells adhering to LNs. In conclusion, our findings suggest that remodeled HEVs are correlated with LN metastasis of OPSCC and play important role in this process by preparing premetastatic soil for cancer cell metastasis.


Asunto(s)
Carcinoma de Células Escamosas/patología , Endotelio Vascular/patología , Neoplasias de la Boca/patología , Neoplasias Faríngeas/patología , Vénulas/patología , Carcinoma de Células Escamosas/secundario , Línea Celular Tumoral , Humanos , Selectina L/genética , Selectina L/metabolismo , Metástasis Linfática
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(10): 920-3, 2013 Oct.
Artículo en Chino | MEDLINE | ID: mdl-24378132

RESUMEN

OBJECTIVE: To evaluate the safety of meningococcal group AC bivalent polysaccharide conjugate vaccine among children aged 5-24 months old. METHODS: From July 2011 to June 2012, a total of 34 411 children aged 5-24 month-old who voluntarily vaccinated meningococcal group AC bivalent polysaccharide conjugate vaccine in Zhongshan city were included. The adverse effects within 72 hours were recorded and analyzed. RESULTS: 34 411 children were recruited, including 18 708 boys (54.36%), whose mean age were ( 11.4 ± 3.9 ) months old.Within 72 hours, the incidence rates of local adverse effects were 0.76% (261/34 411) for erythema,0.57% (197/34 411) for sclerosis,0.56% (191/34 411) for swelling,0.42% (143/34 411) for pain,0.15% (53/34 411) for pruritus, and 0.15% (50/34 411) for rash on the injection site. The overall incidence rate of local adverse effects was 1.61% (554/34 411; 95%CI:1.48%-1.74%). The incidence rates of systemic adverse effects were 0.98% (312/34 411) for fever,0.48% (164/34 411) for anorexia,0.31% (108/34 411) for diarrhea,0.29% (100/34 411) for malaise,0.20% (70/34 411) for nausea and vomiting, and 0.08% (26/34 411) for headache. The overall incidence rate of systemic adverse effects was 1.64% (565/34 411; 95%CI:1.51%-1.78%).25 children (0.07%) had hyperpyrexia ( > 39°C), and the time of duration lasted less than 48 hours.16 children (0.05%) had symptoms of cold, such as cough and catarrh.No accident and other serious events were reported. The incidence rate of systemic adverse effects among boys was 1.79% (334/18 708), which was higher than that of girls (1.47%, 231/15 703), the difference showed statistical significance (χ(2) = 5.22, P < 0.01). The incidence rate of systemic adverse effects among children aged 5-12 month-old was 1.78% (411/23 113), which was higher than that among children aged 13-24 month-old (1.36%, 154/11 298), the difference showed statistical significance (χ(2) = 8.10, P < 0.01). The incidence rate of local adverse effects in children vaccinated the first dose was 1.72% (536/31 129), which was higher than that in children vaccinated the second or third dose (0.55%, 18/3282), the difference showed statistical significance (χ(2) = 25.81, P < 0.01). The incidence rate of systemic adverse effects in children vaccinated the first dose was 1.73% (539/31 129), which was higher than that in children vaccinated the second or third dose (0.79%, 26/5282), whose difference also showed statistical significance (χ(2) = 16.22, P < 0.01). CONCLUSION: The safety of meningococcal group AC bivalent polysaccharide conjugate vaccine among children aged 5-24 months old is relative good.


Asunto(s)
Meningitis Meningocócica/prevención & control , Vacunas Meningococicas/administración & dosificación , Femenino , Humanos , Lactante , Masculino , Meningitis Meningocócica/microbiología , Vacunas Meningococicas/efectos adversos , Vacunas Meningococicas/inmunología , Neisseria meningitidis Serogrupo A , Neisseria meningitidis Serogrupo C , Polisacáridos Bacterianos/inmunología , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/efectos adversos , Vacunas Conjugadas/inmunología
5.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 47(9): 544-6, 2012 Sep.
Artículo en Chino | MEDLINE | ID: mdl-23141729

RESUMEN

OBJECTIVE: To explore a method for ectopic prefabrication of mandible with vascular pedicle. METHODS: Cancellous bone blocks harvested from the dog ribs were packaged with mandible-shaped titanium mesh scaffold and implanted into latissimus dorsi of dog with thoracodorsal artery and vein through the scaffold. After 12 weeks, bone formation and vascularization were evaluated by gross inspection, histological examination and immunohistochemistry. RESULTS: Vascularized mandible with thoracodorsal artery and vein were formed and histological staining and immunohistochemisty confirmed new bone formation and vascularization. CONCLUSIONS: There is feasibility for ectopic prefabrication of vascularized mandible graft using cancellous ribs, which provides a new method for mandibular defect reconstruction. Experimental study on ectopic prefabrication of vascularized mandible graft with autogenous ribs.


Asunto(s)
Trasplante Óseo/métodos , Mandíbula/cirugía , Osteogénesis , Costillas/cirugía , Ingeniería de Tejidos/métodos , Animales , Perros , Femenino , Masculino , Procedimientos de Cirugía Plástica/métodos , Trasplante Autólogo
6.
Exp Cell Res ; 318(14): 1707-15, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-22664325

RESUMEN

Fusion between cancer cells and host cells, including endothelial cells, may strongly modulate the biological behavior of tumors. However, no one is sure about the driving factors and underlying mechanism involved in such fusion. We hypothesized in this study that inflammation, one of the main characteristics in tumor microenvironment, serves as a prominent catalyst for fusion events. Our results showed that oral cancer cells can fuse spontaneously with endothelial cells in co-culture and inflammatory cytokine tumor necrosis factor-α (TNF-α) increased fusion of human umbilical vein endothelium cells and oral cancer cells by up to 3-fold in vitro. Additionally, human oral squamous cell carcinoma cell lines and 35 out of 50 (70%) oral squamous carcinoma specimens express VLA-4, an integrin, previously implicated in fusions between human peripheral blood CD34-positive cells and murine cardiomyocytes. Expression of VCAM-1, a ligand for VLA-4, was evident on vascular endothelium of oral squamous cell carcinoma. Moreover, immunocytochemistry and flow cytometry analysis revealed that expression of VCAM-1 increased obviously in TNF-α-stimulated endothelial cells. Anti-VLA-4 or anti-VCAM-1 treatment can decrease significantly cancer-endothelial adhesion and block such fusion. Collectively, our results suggested that TNF-α could enhance cancer-endothelial cell adhesion and fusion through VCAM-1/VLA-4 pathway. This study provides insights into regulatory mechanism of cancer-endothelial cell fusion, and has important implications for the development of novel therapeutic strategies for prevention of metastasis.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Células Endoteliales/metabolismo , Integrina alfa4beta1/metabolismo , Neoplasias de la Boca/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Carcinoma de Células Escamosas/patología , Adhesión Celular , Fusión Celular , Células Endoteliales/patología , Humanos , Integrina alfa4beta1/biosíntesis , Neoplasias de la Boca/patología , Células Tumorales Cultivadas , Molécula 1 de Adhesión Celular Vascular/biosíntesis
7.
Bioorg Med Chem Lett ; 19(15): 4410-5, 2009 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19500976

RESUMEN

As a continuation of our efforts to discover and develop the 3-aryl-5-aryl-1,2,4-oxadiazole series of apoptosis inducers as potential anticancer agents, we explored substitutions at the 2- and 3-positions of the 3-aryl group to improve the aqueous solubility properties and identify development candidates. A small substitution such as methyl or hydroxymethyl at the 2-position was well tolerated. This modification, in combination with a 3-substituted furan ring as the 5-aryl group, resulted in 4g and 4h, which have improved solubility properties. Compound 4g was found to have good in vivo efficacy in animal studies via intravenous administration.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Química Farmacéutica/métodos , Oxadiazoles/síntesis química , Animales , Línea Celular Tumoral , Técnicas Químicas Combinatorias , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Infusiones Intravenosas , Ratones , Modelos Químicos , Estructura Molecular , Trasplante de Neoplasias , Oxadiazoles/farmacología , Solubilidad , Relación Estructura-Actividad , Agua/química
8.
Bioorg Med Chem ; 17(7): 2852-8, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19282188

RESUMEN

1-(2-(2,5-Dimethoxyphenylthio)benzylidene)semicarbazide (2a) was discovered as a potent apoptosis inducer through our cell based HTS assay. SAR study led to the discovery of a more aqueous soluble analog (2-(2,5-dimethoxyphenylthio)-6-methoxybenzylideneamino)guanidine (5e) with EC(50) value of 60 nM in the caspase activation assay and GI(50) value of 62 nM in the growth inhibition assay in T47D cells. Compound 5e was found to be an inhibitor of tubulin polymerization and efficacious in a MX-1 breast tumor model.


Asunto(s)
Antineoplásicos/química , Apoptosis , Compuestos de Bencilideno/química , Guanidinas/química , Semicarbacidas/química , Moduladores de Tubulina/química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Compuestos de Bencilideno/síntesis química , Compuestos de Bencilideno/farmacología , Línea Celular Tumoral , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Guanidinas/síntesis química , Guanidinas/farmacología , Humanos , Semicarbacidas/farmacología , Relación Estructura-Actividad , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/farmacología
9.
Cancer Lett ; 274(2): 243-9, 2009 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-19008038

RESUMEN

Oncogene addiction due to Myc deregulation has been identified in a variety of tumor types. In order to identify pharmacological agents that cause selective apoptosis in tumors with deregulated Myc expression, we designed a cell-based screening assay based on our Anti-cancer Screening Apoptosis Program (ASAP) technology targeting increased activity in a "Myc-addicted" cancer cell panel. We have identified a novel set of substituted 4-aryl-3-(3-aryl-1-oxo-2-propenyl)-2(1H)-quinolinones that activates apoptosis in cancer cell lines with deregulated Myc, but show low activity in cell lines where Myc is not deregulated. Apoptosis induced by these compounds is rapid, and is associated with a significant downregulation of Myc protein. Selective knockdown of Myc levels in these cells by RNA interference increased sensitivity to apoptosis with compound treatment. By targeting the Myc pathway in Myc-addicted cancer cells, we have identified a novel class of apoptotic inducers that selectively and efficiently target cancer cells with deregulated Myc.


Asunto(s)
Apoptosis/efectos de los fármacos , Genes myc , Quinolonas/farmacología , Caspasas/metabolismo , Ciclo Celular , Línea Celular Tumoral , Regulación hacia Abajo , Activación Enzimática , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Reacción en Cadena de la Polimerasa , Interferencia de ARN , ARN Interferente Pequeño , Ubiquitinación
10.
Bioorg Med Chem Lett ; 18(23): 6259-64, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18952423

RESUMEN

1-Benzoyl-3-cyanopyrrolo[1,2-a]quinoline (2a) was identified as a novel apoptosis inducer through our caspase- and cell-based high-throughput screening assay. Compound 2a had good activity against several breast cancer cell lines but was much less active against several other cancer cell lines. SAR studies of 2a found that substitution at the 4-position of the 1-benzoyl group was important for activity. Replacing the 3-cyano group by an ester or ketone group led to inactive compounds. Interestingly, 4-substituted analogs such as 1-(4-(1H-imidazol-1-yl)benzoyl)-3-cyanopyrrolo[1,2-a]quinoline (2k) were found to be broadly and highly active in the caspase activation assay as well as in the cell growth inhibition assay with low nM EC(50) and GI(50) values in human breast cancer cells T47D, human colon cancer cells HCT116, and hepatocellular carcinoma cancer cells SNU398. Compound 2a was found not to inhibit tubulin polymerization up to 50 microM, while 2k was found to inhibit tubulin polymerization with an IC(50) value of 5 microM, indicating that certain substituents at the 4-position of the 1-benzoyl group can change the mechanism of action.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Quinolinas/síntesis química , Quinolinas/farmacología , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Técnicas Químicas Combinatorias , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células HCT116 , Humanos , Estructura Molecular , Quinolinas/química , Relación Estructura-Actividad , Moduladores de Tubulina/química
11.
Bioorg Med Chem ; 16(1): 222-31, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-17950608

RESUMEN

We report the discovery and SAR study of a series of N-phenyl-1H-pyrazolo[3,4-b]quinolin-4-amines as potent inducers of apoptosis. N-(3-Acetylphenyl)-2,3-dihydro-1H-cyclopenta[b]quinolin-9-amine (2) was discovered through our cell- and caspase-based HTS assays as an inducer of apoptosis. Compound 2 is active against cancer cells derived from several human solid tumors, with EC(50) values ranging from 400 to 700 nM. SAR study of hit 2 led to the discovery of N-phenyl-1H-pyrazolo[3,4-b]quinolin-4-amines as a novel series of potent apoptosis inducers, with 1,3-dimethyl-N-(4-propionylphenyl)-1H-pyrazolo[3,4-b]quinolin-amine (6b) having EC(50) values ranging from 30 to 70 nM in cancer cells. These compounds also demonstrated potent activity in the cell growth inhibition assay, with GI(50) values of 16-42 nM for compound 6b.


Asunto(s)
Antineoplásicos/química , Apoptosis/efectos de los fármacos , Quinolinas/química , Quinolinas/farmacología , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Relación Estructura-Actividad , Células Tumorales Cultivadas
12.
Artículo en Chino | MEDLINE | ID: mdl-17633821

RESUMEN

OBJECTIVE: To evaluate the effect of the intervention measures for schistosomiasis control adapted to the ecological environment changes in Jiang Han plain caused by the establishment of the Three Gorges Dam. METHODS: Four villages in Qianjiang City were selected to implement paddy-upland rotation, crawfish-paddy alternation, water control and soil improvement, and adjusting agricultural structure to rebuild the waterlogging low yielding land and to change the snail habitat environment respectively. The snail habitat area, mean density of living snails and prevalence of schistosomiasis in human and cattle were compared with those of the control villages. Miracidia hatching methods were used to examine the prevalence in human and cattle. RESULTS: In the four experimental villages, the snail-ridden area decreased by 100%, 51.35%, 62.16% and 87.88% respectively; mean density of living snails decreased by 100%, 69.41%, 52.30% and 75.77%, with a t value of 9.37, 4.91, 2.31 and 9.16, I'<0.01. Human prevalence of schistosomiasis in 2005 in village with crawfish-paddy alteration decreased significantly than control (chi2=39.84, I'<0.01); decreased by 73.10% in village with water control and soil improvement in 1990 than in 1987 (chi2=236.10, P<0.01). CONCLUSION: Implementation of the four intervention measures reaches a remarkable benefit in reforming snail habitat and protecting environment, which can be recommended to the inner embankment type endemic regions.


Asunto(s)
Ecosistema , Esquistosomiasis Japónica/prevención & control , Caracoles/parasitología , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , China/epidemiología , Humanos , Densidad de Población , Prevalencia , Ríos , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/transmisión , Caracoles/crecimiento & desarrollo
13.
J Med Chem ; 49(3): 1198-201, 2006 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-16451084

RESUMEN

This paper describes the design and synthesis of dipeptidyl N,N-dimethyl glutaminyl fluoromethyl ketones (fmk) as severe acute respiratory syndrome coronovirus (SARS-CoV) inhibitors. The compounds were tested against SARS-CoV-induced cell death in Vero or CaCo2 cells as a measurement of the inhibiting effects of the compounds on the replication of the virus. Z-Leu-Gln(NMe(2))-fmk (6a) was found to be a potent inhibitor with low toxicity in cells, protecting cells with an EC(50) value of 2.5 microM and exhibiting a selectivity index of >40.


Asunto(s)
Antivirales/síntesis química , Dipéptidos/síntesis química , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/efectos de los fármacos , Animales , Antivirales/química , Antivirales/farmacología , Células CACO-2 , Muerte Celular/efectos de los fármacos , Chlorocebus aethiops , Dipéptidos/química , Dipéptidos/farmacología , Diseño de Fármacos , Humanos , Células Vero , Replicación Viral
14.
J Med Chem ; 48(16): 5215-23, 2005 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-16078840

RESUMEN

We have identified 5-(3-chlorothiophen-2-yl)-3-(4-trifluoromethylphenyl)-1,2,4-oxadiazole (1d) as a novel apoptosis inducer through our caspase- and cell-based high-throughput screening assay. Compound 1d has good activity against several breast and colorectal cancer cell lines but is inactive against several other cancer cell lines. In a flow cytometry assay, treatment of T47D cells with 1d resulted in arrest of cells in the G(1) phase, followed by induction of apoptosis. SAR studies of 1d showed that the 3-phenyl group can be replaced by a pyridyl group, and a substituted five-member ring in the 5-position is important for activity. 5-(3-Chlorothiophen-2-yl)-3-(5-chloropyridin-2-yl)-1,2,4-oxadiazole (4l) has been found to have in vivo activity in a MX-1 tumor model. Using a photoaffinity agent, the molecular target has been identified as TIP47, an IGF II receptor binding protein. Therefore, our cell-based chemical genetics approach for the discovery of apoptosis inducers can identify potential anticancer agents as well as their molecular targets.


Asunto(s)
Antineoplásicos/síntesis química , Apoptosis , Oxadiazoles/síntesis química , Tiofenos/síntesis química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Caspasas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Proteínas de Unión al ADN/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Activación Enzimática , Citometría de Flujo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Oxadiazoles/química , Oxadiazoles/farmacología , Perilipina-3 , Proteínas Gestacionales/metabolismo , Receptor IGF Tipo 2/metabolismo , Relación Estructura-Actividad , Tiofenos/química , Tiofenos/farmacología , Proteínas de Transporte Vesicular
15.
Proc Natl Acad Sci U S A ; 102(34): 12095-100, 2005 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-16103367

RESUMEN

Transferrin receptor (TfR) has been shown to be significantly overexpressed in different types of cancers. We discovered TfR as a target for gambogic acid (GA), used in traditional Chinese medicine and a previously undiscovered link between TfR and the rapid activation of apoptosis. The binding site of GA on TfR is independent of the transferrin binding site, and it appears that GA potentially inhibits TfR internalization. Down-regulation of TfR by RNA interference decreases sensitivity to GA-induced apoptosis, further supporting TfR as the primary GA receptor. In summary, GA binding to TfR induces a unique signal leading to rapid apoptosis of tumor cells. These results suggest that GA may provide an additional approach for targeting the TfR and its use in cancer therapy.


Asunto(s)
Apoptosis/fisiología , Medicamentos Herbarios Chinos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Receptores de Transferrina/metabolismo , Xantonas/farmacología , Apoptosis/efectos de los fármacos , Sitios de Unión , Línea Celular Tumoral , Cartilla de ADN , Medicamentos Herbarios Chinos/uso terapéutico , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Microscopía Electrónica , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Xantonas/uso terapéutico
16.
Mol Cancer Ther ; 4(5): 761-71, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15897240

RESUMEN

A novel series of 3,5-diaryl-oxadiazoles was identified as apoptosis-inducing agents through our cell and chemical genetics-based screening assay for compounds that induce apoptosis using a chemical genetics approach. Several analogues from this series including MX-74420 and MX-126374 were further characterized. MX-126374, a lead compound from this series, was shown to induce apoptosis and inhibit cell growth selectively in tumor cells. To elucidate the mechanism(s) by which this class of compounds alters the signal transduction pathway that ultimately leads to apoptosis, expression profiling using the Affymetrix Gene Chip array technology was done along with other molecular and biochemical analyses. Interestingly, we have identified several key genes (cyclin D1, transforming growth factor-beta1, p21, and insulin-like growth factor-BP3) that are altered in the presence of this compound, leading to characterization of the pathway for activation of apoptosis. MX-126374 also showed significant inhibition of tumor growth as a single agent and in combination with paclitaxel in murine tumor models. Using photoaffinity labeling, tail-interacting protein 47, an insulin-like growth factor-II receptor binding protein, was identified as the molecular target. Further studies indicated that down-regulation of tail-interacting protein 47 in cancer cells by small interfering RNA shows a similar pathway profile as compound treatment. These data suggest that 3,5-diaryl-oxadiazoles may be a new class of anticancer drugs that are tumor-selective and further support the discovery of novel drugs and drug targets using chemical genetic approaches.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Activación Enzimática/efectos de los fármacos , Perfilación de la Expresión Génica , Oxadiazoles/farmacología , Animales , Antineoplásicos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Pollos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Femenino , Humanos , Inmunoglobulinas/inmunología , Glándulas Mamarias Humanas/citología , Glándulas Mamarias Humanas/efectos de los fármacos , Glándulas Mamarias Humanas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Oxadiazoles/síntesis química , Oxadiazoles/química , Receptor IGF Tipo 2/genética , Receptor IGF Tipo 2/inmunología , Receptor IGF Tipo 2/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1
17.
Bioorg Med Chem ; 12(13): 3649-55, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15186849

RESUMEN

A series of indole-2-carboxylic acid benzylidene-hydrazides has been identified as a new class of potent apoptosis inducers through a novel cell-based caspase HTS assay. The screening hit, 5-chloro-3-methyl-indole-2-carboxylic acid (4-nitrobenzylidene)-hydrazide (3a), was found to arrest T47D cells in G(2)/M and to induce apoptosis as measured by the flow cytometric analysis assay. A SAR study was carried out by modification of the substitutions on the indole and benzene rings. Substitution at the 3-position of the indole ring was found to be important for apoptotic activity. A 20-fold increase of apoptotic activity was achieved from screening hit 3a to 5-methyl-3-phenyl-indole-2-carboxylic acid (4-methylbenzylidene)-hydrazide (9a) and 5-chloro-3-phenyl-indole-2-carboxylic acid (4-nitrobenzylidene)-hydrazide (9b), with EC(50) value of 0.1microM in the caspase activation assay in T47D breast cancer cells. Compound 9b also was found to be highly active in a standard growth inhibition assay with a GI(50) value of 0.9microM in T47D cells. Compound 3a and its analogs were found to inhibit tubulin polymerization, which is the most probable primary mechanism of action of these compounds.


Asunto(s)
Apoptosis/efectos de los fármacos , Hidrazinas/química , Hidrazinas/farmacología , Indoles/química , Ácidos Carboxílicos , Caspasas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Humanos , Hidrazinas/síntesis química , Estructura Molecular , Relación Estructura-Actividad
18.
Bioorg Med Chem ; 12(2): 309-17, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14723951

RESUMEN

Gambogic acid (2), a natural product isolated from the resin of Garcinia hurburyi tree, was discovered to be a potent apoptosis inducer using our cell- and caspase-based high-throughput screening assays. Gambogic acid was found to have an EC(50) of 0.78 microM in the caspase activation assay in T47D breast cancer cells. The apoptosis-inducing activity of gambogic acid was further characterized by a nuclear fragmentation assay and flow cytometry analysis in human breast tumor cells T47D. Gambogic acid was found to induce apoptosis independent of cell cycle, which is different from paclitaxel that arrests cells in the G2/M phase. To understand the structure-activity relationship (SAR) of gambogic acid, derivatives of 2 with modifications to different function groups were prepared. SAR studies of gambogic acid, as measured by the caspase activation assay, showed that the 9,10 carbon-carbon double bond of the alpha,beta-unsaturated ketone is important for biological activity, while the 6-hydroxy and 30-carboxy group can tolerate a variety of modifications. The importance of the 9,10 carbon-carbon double bond was confirmed by the traditional growth inhibition assay. The high potency of 2 as an inducer of apoptosis, its novel mechanism of action, easy isolation and abundant supply, as well as the fact that it is amenable to chemical modification, makes gambogic acid an attractive molecule for the development of anticancer agents.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Xantonas/química , Xantonas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Caspasas/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Relación Estructura-Actividad
19.
Bioconjug Chem ; 14(2): 458-63, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12643757

RESUMEN

N-Pentafluorobenzoyl-R110 (1a) and N-(2,3,4,5-tetrafluorobenzoyl)-R110 (1b) with enhanced cell retention properties, were prepared from rhodamine 110 (R-110) and the corresponding polyfluorobenzoyl chloride. N-Ac-DEVD-N'-pentafluorobenzoyl-R110 (3a) and N-Ac-DEVD-N'-(2,3,4,5-tetrafluorobenzoyl)-R110 (3b) were prepared as tetrapeptide substrates for caspases. Substrate 3b was efficiently cleaved by human recombinant caspase-3 in an enzyme assay. Substrate 3b also was efficiently cleaved in cell-based apoptosis assays. After cleavage in apoptotic cells by activated caspases, the substrate becomes fluorescent as measured by flow cytometry. These substrates should prove useful in cell-based assays for studying apoptosis inducers and inhibitors.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Cumarinas/química , Colorantes Fluorescentes/química , Oligopéptidos/química , Carcinógenos/farmacología , Caspasa 3 , Caspasas/química , Permeabilidad de la Membrana Celular , Citometría de Flujo , Células HL-60 , Humanos , Espectroscopía de Resonancia Magnética , Proteínas Recombinantes/química , Rodaminas/química , Estaurosporina/farmacología , Especificidad por Sustrato
20.
Biochem Pharmacol ; 63(6): 1165-76, 2002 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11931850

RESUMEN

The enzyme steroid 5 alpha-reductase (EC 1.3.99.5) catalyzes the NADPH-dependent reduction of the double bond of a variety of 3-oxo-Delta(4) steroids including the conversion of testosterone to 5 alpha-dihydrotestosterone. In humans, 5 alpha-reductase activity is critical for certain aspects of male sexual differentiation, and may be involved in the development of benign prostatic hyperplasia, alopecia, hirsutism, and prostate cancer. Certain natural products contain components that are inhibitors of 5 alpha-reductase, such as the green tea catechin (-)-epigallocatechin gallate (EGCG). EGCG shows potent inhibition in cell-free but not in whole-cell assays of 5 alpha-reductase. Replacement of the gallate ester in EGCG with long-chain fatty acids produced potent 5 alpha-reductase inhibitors that were active in both cell-free and whole-cell assay systems. Other flavonoids that were potent inhibitors of the type 1 5alpha-reductase include myricetin, quercitin, baicalein, and fisetin. Biochanin A, daidzein, genistein, and kaempferol were much better inhibitors of the type 2 than the type 1 isozyme. Several other natural and synthetic polyphenolic compounds were more effective inhibitors of the type 1 than the type 2 isozyme, including alizarin, anthrarobin, gossypol, nordihydroguaiaretic acid, caffeic acid phenethyl ester, and octyl and dodecyl gallates. The presence of a catechol group was characteristic of almost all inhibitors that showed selectivity for the type 1 isozyme of 5 alpha-reductase. Since some of these compounds are consumed as part of the normal diet or in supplements, they have the potential to inhibit 5 alpha-reductase activity, which may be useful for the prevention or treatment of androgen-dependent disorders. However, these compounds also may adversely affect male sexual differentiation.


Asunto(s)
Inhibidores de 5-alfa-Reductasa , Inhibidores Enzimáticos/farmacología , Flavonoides , Fenoles/farmacología , Polímeros/farmacología , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , Animales , Catequina/análogos & derivados , Catequina/química , Catequina/farmacología , Extractos Celulares , Sistema Libre de Células , Inhibidores Enzimáticos/química , Humanos , Cinética , Fenoles/química , Polímeros/química , Ratas , Relación Estructura-Actividad , Té/química
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