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1.
Eur J Med Chem ; 259: 115709, 2023 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-37567056

RESUMEN

Poly(ADP-ribose) polymerase 1 (PARP1) inhibitors can selectively kill homologous recombination (HR) deficient cancer cells and elicit anticancer effect through a mechanism of synthetic lethality. In this study, we designed, synthesized and pharmacologically evaluated a series of [1,2,4]triazolo[4,3-a]pyrazine derivatives as a class of potent PARP1 inhibitors. Among them, compounds 17m, 19a, 19c, 19e, 19i and 19k not only displayed more potent inhibitory activities (IC50s < 4.1 nM) than 9 and 1 against PARP1, but also exhibited nanomolar range of antiproliferative effects against MDA-MB-436 (BRCA1-/-, IC50s < 1.9 nM) and Capan-1 (BRCA2-/-, IC50s < 21.6 nM) cells. Notably, 19k significantly inhibited proliferation of resistant Capan-1 cells (IC50s < 0.3 nM). Collectively, the newly discovered PARP1 inhibitors act as a useful pharmacological tool for investigating the mechanism of acquired resistance to PARP1 inhibitors, and may also represent promising therapeutic agents for the treatment of HR deficient cancers with the potential to overcome the acquired resistance.


Asunto(s)
Neoplasias , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Humanos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Poli(ADP-Ribosa) Polimerasa-1 , Neoplasias/tratamiento farmacológico , Recombinación Homóloga , Línea Celular Tumoral
2.
EMBO Mol Med ; 15(3): e16235, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36652375

RESUMEN

Poly-ADP-ribose polymerase (PARP) inhibitors (PARPi) have shown great promise for treating BRCA-deficient tumors. However, over 40% of BRCA-deficient patients fail to respond to PARPi. Here, we report that thioparib, a next-generation PARPi with high affinity against multiple PARPs, including PARP1, PARP2, and PARP7, displays high antitumor activities against PARPi-sensitive and -resistant cells with homologous recombination (HR) deficiency both in vitro and in vivo. Thioparib treatment elicited PARP1-dependent DNA damage and replication stress, causing S-phase arrest and apoptosis. Conversely, thioparib strongly inhibited HR-mediated DNA repair while increasing RAD51 foci formation. Notably, the on-target inhibition of PARP7 by thioparib-activated STING/TBK1-dependent phosphorylation of STAT1, triggered a strong induction of type I interferons (IFNs), and resulted in tumor growth retardation in an immunocompetent mouse model. However, the inhibitory effect of thioparib on tumor growth was more pronounced in PARP1 knockout mice, suggesting that a specific PARP7 inhibitor, rather than a pan inhibitor such as thioparib, would be more relevant for clinical applications. Finally, genome-scale CRISPR screening identified PARP1 and MCRS1 as genes capable of modulating thioparib sensitivity. Taken together, thioparib, a next-generation PARPi acting on both DNA damage response and antitumor immunity, serves as a therapeutic potential for treating hyperactive HR tumors, including those resistant to earlier-generation PARPi.


Asunto(s)
Interferón Tipo I , Neoplasias , Animales , Ratones , Línea Celular Tumoral , Reparación del ADN , Recombinación Homóloga , Interferón Tipo I/genética , Interferón Tipo I/uso terapéutico , Neoplasias/genética , Ftalazinas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Reparación del ADN por Recombinación , Proteínas de Unión al ARN/genética , Resistencia a Antineoplásicos
3.
Front Pediatr ; 10: 1001775, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36299686

RESUMEN

We initially described two children who developed Guillain-Barré syndrome (GBS) complicated by rhabdomyolysis (RML), and reviewed five adult patients from the literature. Through analysis of the clinical features, laboratory examination, treatment and prognostic data from these seven patients, we found that when GBS "meets" RML, the most prominent characteristics were the following: male dominance; limb weakness, pain and respiratory failure could be caused by multiple factors; limb weakness and respiratory muscle paralysis were more serious than with GBS alone; and the probability of mechanical ventilation was increased. Neuroelectrophysiological studies revealed axonal lesions. Close monitoring and timely identification and intervention to remedy potentially fatal complications such as electrolyte disorder multisystem complications and kidney injury are crucial. With plasma exchange, peritoneal dialysis and supportive treatment, the long-term outcome of most patients was satisfactory.

5.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(9): 964-969, 2020 Sep.
Artículo en Chino | MEDLINE | ID: mdl-32933627

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of tacrolimus in the treatment of children with myasthenia gravis (MG). METHODS: A total of 28 children with MG were treated with tacrolimus. MG-Activities of Daily Living (MG-ADL) scale was used to assess clinical outcome and safety after 1, 3, 6, 9, and 12 months of treatment. RESULTS: After tacrolimus treatment, the MG-ADL score at 1, 3, 6, 9 and 12 months was lower than that at baseline (P<0.05), and the MG-ADL score showed a gradually decreasing trend. The response rates to tacrolimus treatment at 1, 3, 6, 9, and 12 months were 59%, 81%, 84%, 88%, and 88% respectively. At 6, 9, 12, and 18 months of treatment, 4, 13, 14, and 15 children respectively were withdrawn from prednisone. No recurrence was observed during treatment. Major adverse reactions/events were asymptomatic reduction in blood magnesium in 5 children and positive urine occult blood in 1 child, which turned negative without special treatment, and tacrolimus was not stopped due to such adverse reactions/events. One child was withdrawn from tacrolimus due to recurrent vomiting. According to CYP3A5 genotypes, all of the patients were divided into two groups: slow metabolic type (n=19) and non-slow metabolic type (fast metabolic type + intermediate type; n=9). The non-slow metabolism group received a higher dose of tacrolimus, but had a lower trough concentration of tacrolimus than the slow metabolism group (P<0.05). The slow metabolism group had a higher response rates to tacrolimus treatment than the non-slow metabolism group (P<0.05). CONCLUSIONS: Tacrolimus appears to be effective and safe in the treatment of children with MG and is thus an option for immunosuppressive therapy. CYP3A5 genotyping has a certain guiding significance for determining the dosage of tacrolimus.


Asunto(s)
Miastenia Gravis , Tacrolimus/uso terapéutico , Actividades Cotidianas , Niño , Humanos , Inmunosupresores , Miastenia Gravis/tratamiento farmacológico , Recurrencia Local de Neoplasia
6.
Front Genet ; 11: 126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32194620

RESUMEN

Familial hemophagocytic lymphohistiocytosis Type 2 (FHL2) associated central nervous system (CNS) involvement is less understood in children, especially when considering neurologic manifestations as part of the initial presentation. We conducted a retrospective review of the clinical manifestations and genetic abnormality of four Han Chinese children with FHL2 who were patients at the neurology department of Beijing Children's Hospital from November 2015 to October 2018. These four patients initially manifested CNS symptoms in their disease presentation, and all four patients were misdiagnosed as having ademyelinating disease, such as acute disseminated encephalomyelitis and multiple sclerosis. Given these misdiagnoses, it is important that general physicians and pediatricians maintain awareness of the possibility of FHL2 as a differential diagnosis. These four cases included neurologic manifestations including seizures, ataxia, spasticity, gait disorder, and coma. Bilateral abnormal signals in the cerebrum, including in white matter, gray matter, and junctions were discovered. Enhanced magnetic resonance imaging (MRI) in these patients showed spot or ring enhancement and/or hemorrhage. These patients all possessed a compound heterozygote mutation PRF1 gene. Whole exome sequencing analysis revealed seven different mutations (three novel mutations) spread over the PRF1 gene and a heterozygous missense mutation c.1349C > T [p.T450M] that was present in two patients. Three novel mutations, c.634T > C[p.Y212H], c.1083_1094del[p.361_364del], and c.1306G > T [p.D436Y], were discovered and through in silico analysis were discovered to be deleterious. Neurologic manifestations were the initial symptoms of FHL2 in these patients in addition to the expected leukopenia and hepatosplenomegaly. Whole exome sequencing of PRF1 for patients with similar presentations would facilitate prompt and accurate diagnosis and treatment.

7.
Sci Rep ; 8(1): 724, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29335596

RESUMEN

Circulating miRNAs are proposed as a biomarker of heart disease. This study evaluated whether circulating miRNAs could be used as a biomarker for childhood dilated cardiomyopathy (CDCM). A total of 28 participants were enrolled in a discovery set, including patients with CDCM (n = 16) and healthy children (n = 12). The cardiac function of patients with CDCM was characterized by echocardiography and serum miRNA profiles of all participants were assessed by miRNA sequencing. After miRNA profiling, we quantitatively confirmed 148 regulated miRNAs in patients with CDCM compared with healthy subjects, and none were downregulated. Validation of candidate miRNAs was assessed by quantitative real-time polymerase chain reaction in other patients with CDCM (n = 30) and healthy controls (n = 16). A unique signature comprising mir-142-5p, mir-143-3p, mir-27b-3p, and mir-126-3p differentiated patients with CDCM from healthy subjects. Importantly, we observed an increase in mir-126-3p or let-7g in parallel with a robust decrease in the ejection fraction in patients with CDCM, which could differentiate heart failure patients from non-heart failure patients with CDCM. Moreover, mir-126-3p and let-7g were significantly negatively associated with the left ventricular ejection fraction. This study shows that a signature of four serum miRNAs may be a potential biomarker for diagnosing CDCM and assessing heart failure.


Asunto(s)
Biomarcadores/sangre , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/patología , MicroARN Circulante/sangre , Cardiomiopatía Dilatada/diagnóstico por imagen , Niño , Preescolar , Ecocardiografía , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
8.
Acta Pharmacol Sin ; 38(7): 1038-1047, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28414200

RESUMEN

Over half of patients with BRCA1-deficient cancers do not respond to treatment with poly(ADP-ribose) polymerase (PARP) inhibitors. In this study, we report that a combination of 53BP1 and BRCA1 may serve as a biomarker of PARP inhibitor sensitivity. Based on the mRNA levels of four homologous recombination repair (HR) genes and PARP inhibitor sensitivity, we selected BRCA1-deficient MDA-MB-436 cells to conduct RNA interference. Reducing expression of 53BP1, but not the other three HR genes, was found to lower simmiparib sensitivity. Additionally, we generated 53BP1-/-/BRCA1-/- clonal variants by the transcription activator-like effector nuclease (TALEN) technique and found that depleting 53BP1 impaired PARP inhibitor sensitivity with a 36.7-fold increase in their IC50 values. Consistent with its effect on PARP inhibitor sensitivity, 53BP1 loss alleviated cell cycle arrest and apoptosis and partially restored HR function. Importantly, 53BP1 depletion dramatically reduced the ability of PARP inhibitors to suppress tumor growth in vivo. The inhibition rate of simmiparib was 74.16% for BRCA1-deficient MDA-MB-436 xenografts, but only 7.79% for 53BP1/BRCA1-deficient xenografts. Re-expressing 53BP1 in the dual-deficient cells restored PARP inhibitor sensitivity and the levels of HR regulators. Considering that at least 10% of BRCA1-deficient breast and ovarian cancers have reduced expression of 53BP1, using a combination of 53BP1 with BRCA1 as a biomarker for patient selection should reduce the number of patients undergoing futile treatment with PARP inhibitors.


Asunto(s)
Antineoplásicos/farmacología , Proteína BRCA1/antagonistas & inhibidores , Biomarcadores de Tumor/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53/antagonistas & inhibidores , Animales , Antineoplásicos/química , Proteína BRCA1/deficiencia , Proteína BRCA1/metabolismo , Biomarcadores de Tumor/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Ratones Desnudos , Estructura Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/química , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/genética , ARN Mensajero/metabolismo , Relación Estructura-Actividad , Proteína 1 de Unión al Supresor Tumoral P53/deficiencia , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo
9.
Theranostics ; 7(4): 974-986, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28382169

RESUMEN

PI3Kα-selective inhibitor BYL719 is currently in phase II/III clinical trial for the treatment of breast cancer, but highly variable response has been observed among patients. We sought to discover predictive biomarker for the efficacy of BYL719 by dissecting the proliferative signaling pathway mediated by PI3K in breast cancer. BYL719 concurrently inhibited the phosphorylation of AKT and ERK in PIK3CA-mutated human breast cancer cells. PI3K-regulated ERK phosphorylation was independent of canonical PDK1/AKT/mTOR pathway, while it was associated with RAF/MEK. Hyper-activation of EGFR or RAS abrogated inhibition of ERK phosphorylation by BYL719. Furthermore, hyper-activation of receptor tyrosine kinases (RTKs) including EGFR, c-MET, FGFR and HER3 but not IGF-1R restored ERK phosphorylation and cell viability suppressed by BYL719, suggesting the discriminative functions of RTKs in cell signaling and proliferation. By profiling 22 breast cancer cell lines, we found that BYL719 was more potent in cell lines where phosphorylation of both AKT and ERK was attenuated than those where only AKT phosphorylation was inhibited. The potency of BYL719 was further found to be significantly correlated with the expression profile of RTKs in breast cancer cells. Specifically, overexpression of EGFR, c-MET and/or FGFR1 forecasted resistance, while overexpression of IGF-1R and/or HER2 predicted sensitivity to BYL719 in breast cancer cells. Similar correlation between BYL719 efficacy and expression profile of RTKs was found in patient-derived xenograft models of breast cancer. Thus, inhibition of ERK phosphorylation by PI3Kα inhibitor BYL719 contributes to its antitumor efficacy and is determined by the converged signaling from RTKs. The expression profile of RTKs in breast cancer tissue could be potentially developed as a predictive biomarker for the efficacy of PI3Kα inhibitors.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Fosfatidilinositol 3-Quinasa Clase I/antagonistas & inhibidores , Resistencia a Medicamentos , Proteínas Tirosina Quinasas/biosíntesis , Tiazoles/uso terapéutico , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Xenoinjertos , Humanos , Ratones SCID , Tiazoles/farmacología , Insuficiencia del Tratamiento
10.
Cancer Lett ; 386: 47-56, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27847302

RESUMEN

Poly(ADP-ribose)polymerase (PARP)1/2 inhibitors have been proved to be clinically effective anticancer drugs. Here we report a new PARP1/2 inhibitor, simmiparib, displaying apparently improved preclinical anticancer activities relative to the first approved inhibitor olaparib. Simmiparib inhibited PARP1/2 approximately 2-fold more potently than olaparib, with more than 90-fold selectivity over the other tested PARP family members. Simmiparib and olaparib caused similar cellular PARP1-DNA trapping. Simmiparib selectively induced the accumulation of DNA double-strand breaks, G2/M arrest and apoptosis in homologous recombination repair (HR)-deficient cells. Consistently, simmiparib showed 26- to 235-fold selectivity in its antiproliferative activity against HR-deficient cells over the corresponding isogenic HR-proficient cells. Notably, its antiproliferative activity was 43.8-fold more potent than that of olaparib in 11 HR-deficient cancer cell lines. Simmiparib also potentiated the proliferative inhibition of several conventional anticancer drugs. Simmiparib reduced the poly(ADP-ribose) formation in HR-deficient cancer cells and xenografts. When orally administered to nude mice bearing xenografts, simmiparib revealed excellent pharmacokinetic properties. Simmiparib caused approximately 10-fold greater growth inhibition than olaparib against HR-deficient human cancer cell- or tissue-derived xenografts in nude mice. Collectively, these findings support the undergoing clinical trials of simmiparib.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Ftalazinas/farmacología , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Administración Oral , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos Clínicos como Asunto , Cricetinae , Roturas del ADN de Doble Cadena , Relación Dosis-Respuesta a Droga , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Genes BRCA1 , Genes BRCA2 , Humanos , Ratones Desnudos , Ftalazinas/administración & dosificación , Ftalazinas/farmacocinética , Piperazinas/farmacología , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/administración & dosificación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacocinética , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Carga Tumoral/efectos de los fármacos , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Oncotarget ; 8(3): 4156-4168, 2017 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-27926532

RESUMEN

The approval of poly(ADP-ribose) polymerase (PARP) inhibitor AZD2281 in 2014 marked the successful establishment of the therapeutic strategy targeting homologous recombination repair defects of cancers in the clinic. However, AZD2281 has poor water solubility, low tissue distribution and relatively weak in vivo anticancer activity, which appears to become limiting factors for its clinical use. In this study, we found that mefuparib hydrochloride (MPH) was a potent PARP inhibitor, possessing prominent in vitro and in vivo anticancer activity. Notably, MPH displayed high water solubility (> 35 mg/ml) and potent PARP1/2 inhibition in a substrate-competitive manner. It reduced poly(ADP-ribose) (PAR) formation, enhanced γH2AX levels, induced G2/M arrest and subsequent apoptosis in homologous recombination repair (HR)-deficient cells. Proof-of-concept studies confirmed the MPH-caused synthetic lethality. MPH showed potent in vitro and in vivo proliferation and growth inhibition against HR-deficient cancer cells and synergistic sensitization of HR-proficient xenografts to the anticancer drug temozolomide. A good relationship between the anticancer activity and the PARP inhibition of MPH suggested that PAR formation and γH2AX accumulation could serve as its pharmacodynamic biomarkers. Its high bioavailability (40%~100%) and high tissue distribution in both monkeys and rats were its most important pharmacokinetic features. Its average concentrations were 33-fold higher in the tissues than in the plasma in rats. Our work supports the further clinical development of MPH as a novel PARP1/2 inhibitor for cancer therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Compuestos Heterocíclicos de 4 o más Anillos/administración & dosificación , Neoplasias/tratamiento farmacológico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/administración & dosificación , Animales , Antineoplásicos/farmacocinética , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dacarbazina/administración & dosificación , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Sinergismo Farmacológico , Haplorrinos , Compuestos Heterocíclicos de 4 o más Anillos/farmacocinética , Humanos , Ratones , Neoplasias/enzimología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacocinética , Ratas , Temozolomida , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Antivir Ther ; 20(6): 583-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25774942

RESUMEN

BACKGROUND: Cytokines are crucial factors in the non-cytolytic antiviral process to inhibit HBV gene expression and replication. Interleukin (IL)-21 has been suggested to play an important role in HBV infection, but it remains unknown whether IL-21 can inhibit HBV replication or how it inhibits HBV replication. METHODS: In this study, we investigated the influence of IL-21 on HBV replication based on human hepatoma Huh7.93 cells co-cultured with human peripheral blood mononuclear cells (PBMCs) and the possible correlation among IL-21, interferon-γ, tumour necrosis factor-α and IL-10. RESULTS: We demonstrated that the decrease of IL-21 expression and the increase of IL-10 expression in PBMCs could promote HBV replication in vitro. We further revealed that IL-21 is not only able to effectively suppress HBV replication directly but also reduce HBV replication by inhibition of IL-10 secretion. CONCLUSIONS: Our results provide important evidence for the non-cytolytic antiviral mechanism mediated by cytokines and their interactions in chronic hepatitis B.


Asunto(s)
ADN Viral/antagonistas & inhibidores , Virus de la Hepatitis B/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Interleucinas/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Línea Celular Tumoral , Técnicas de Cocultivo , ADN Viral/genética , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/crecimiento & desarrollo , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Hepatocitos/inmunología , Hepatocitos/virología , Interacciones Huésped-Patógeno , Humanos , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Interleucinas/genética , Interleucinas/inmunología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/virología , Cultivo Primario de Células , Proteínas Recombinantes/farmacología , Transducción de Señal , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
13.
World J Gastroenterol ; 20(46): 17426-33, 2014 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-25516654

RESUMEN

AIM: To assess the anti-cancer effect of lobaplatin on human gastric cancer cells, and to explore the underlying molecular mechanisms. METHODS: The human gastric cancer cell lines MKN-28, AGS and MKN-45 were used. The cytotoxicity of lobaplatin was detected using an MTS cell proliferation assay. Flow cytometry was used to detect cell apoptosis using Annexin V-FITC Apoptosis Detection Kit. The expression of apoptosis-regulated genes was examined at the protein level using Western blot. RESULTS: Lobaplatin inhibited the proliferation of human gastric cancer cells and induced apoptosis, which may be associated with the up-regulation of Bax expression, poly(ADP-ribose) polymerase (PARP) cleavage, p53 expression and the reduction of Bcl-2 expression. CONCLUSION: The cytotoxicity of lobaplatin may be due to its ability of inducing apoptosis of gastric cancer cells, which would support the potential use of lobaplatin for the therapy of gastric cancer.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ciclobutanos/farmacología , Compuestos Organoplatinos/farmacología , Neoplasias Gástricas/patología , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias Gástricas/metabolismo , Factores de Tiempo
14.
World J Gastroenterol ; 20(48): 18284-95, 2014 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-25561795

RESUMEN

AIM: To construct a tricistronic hepatitis C virus (HCV) replicon with double internal ribosome entry sites (IRESes) of only 22 nucleotides for each, substituting the encephalomyocarditis virus (EMCV) IRESes, which are most often used as the translation initiation element to form HCV replicons. METHODS: The alternative 22-nucleotide IRES, RNA-binding motif protein 3 IRES (Rbm3 IRES), was used to form a tricistronic HCV replicon, to facilitate constructing HCV-harboring stable cell lines and successive antiviral screening using a luciferase marker. Briefly, two sequential Rbm3 IRESes were inserted into bicistronic pUC19-HCV plasmid, consequently forming a tricistronic HCV replicon (pHCV-rep-NeoR-hRluc), initiating the translation of humanized Renilla luciferase and HCV non-structural gene, along with HCV authentic IRES initiating the translation of neomycin resistance gene. The sH7 cell lines, in which the novel replicon RNA stably replicated, were constructed by neomycin and luciferase activity screening. The intracellular HCV replicon RNA, expression of inserted foreign genes and HCV non-structural gene, as well as response to anti-HCV agents, were measured in sH7 cells and cells transiently transfected with tricistronic replicon RNA. RESULTS: The intracellular HCV replicon RNA and expression of inserted foreign genes and HCV non-structural gene in sH7 cells and cells transiently transfected with tricistronic replicon RNA were comparable to those in cells stably or transiently transfected with traditional bicistronic HCV replicons. The average relative light unit in pHCV-rep-NeoR-hRluc group was approximately 2-fold of those in the pUC19-HCV-hRLuc and Tri-JFH1 groups (1.049 × 10(8) ± 2.747 × 10(7) vs 5.368 × 10(7) ± 1.016 × 10(7), P < 0.05; 1.049 × 10(8) ± 2.747 × 10(7) vs 5.243 × 10(7) ± 1.194 × 10(7), P < 0.05), suggesting that the translation initiation efficiency of the first Rbm3 IRES in the two sequential IRESes was stronger than the HCV authentic IRES and EMCV IRES. The fold changes of 72 h/4 h relative light units in the pHCV-rep-NeoR-hRluc and pUC19-HCV-hRLuc groups were similar (159.619 ± 9.083 vs 163.536 ± 24.031, P = 0.7707), and were both higher than the fold change in the Tri-JFH1 group 159.619± 9.083 vs 140.811 ± 9.882, P < 0.05; 163.536 ± 24.031 vs 140.811 ± 9.882, P < 0.05), suggesting that the replication potency of the Rbm3 IRES tricistronic replicon matched the replication of bicistronic replicon and exceeded the potency of EMCV IRES replicon. Replication of tricistronic replicons was suppressed by ribavirin, simvastatin, atorvastatin, telaprevir and boceprevir. Interferon-alpha 2b could not block replication of the novel replicon RNA in sH7 cells. After interferon stimulation, MxA mRNA and protein levels were lower in sH7 than in parental cells. CONCLUSION: Tricistronic HCV replicon with double Rbm3 IRESes could be applied to evaluate the replication inhibition efficacy of anti-HCV agents.


Asunto(s)
Virus de la Encefalomiocarditis/genética , Regulación Viral de la Expresión Génica , Genoma Viral , Hepacivirus/genética , Replicón , Transgenes , Antivirales/farmacología , Línea Celular , Relación Dosis-Respuesta a Droga , Farmacorresistencia Viral/genética , Regulación Viral de la Expresión Génica/efectos de los fármacos , Genes Reporteros , Hepacivirus/efectos de los fármacos , Hepacivirus/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Estabilidad del ARN , ARN Viral/genética , ARN Viral/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Ribosomas/genética , Ribosomas/metabolismo , Factores de Tiempo , Transfección , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo
15.
Indian J Biochem Biophys ; 49(3): 173-81, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22803332

RESUMEN

Colorectal cancer is one of the leading causes of death in the world. Plant-derived products have proven to be valuable sources for discovery and development of unique anticancer drugs. In this study, the inhibitory effects of ethanolic extract of Melia toosendan fruit (EMTF), a traditional medicine in the Chinese Pharmacopeia were evaluated in vitro and in vivo against colon cancer. Human colon cancer cells SW480 and murine colorectal adenocarcinoma cells CT26 were used to investigate cell proliferation. The results showed that EMTF inhibited cell proliferation of SW480 and CT26 by promoting apoptosis as indicated by nuclear chromatin condensation and DNA fragmentation. Through increasing mitochondrial membrane permeability and cytochrome c release from mitochondria, EMTF induced caspase-9 activity which further activated caspase-3 and poly(ADP-ribose) polymerase cleavage, leading the tumor cells to apoptosis. The in vivo results confirmed reduction of tumor volume and apoptotic effects and the side effects were not induced by EMTF. Therefore, EMTF may be an effective chemotherapeutic agent for colon cancer treatment.


Asunto(s)
Neoplasias del Colon/tratamiento farmacológico , Frutas/metabolismo , Melia/química , Extractos Vegetales/farmacología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/enzimología , Adenocarcinoma/patología , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/enzimología , Neoplasias del Colon/patología , Citocromos c/metabolismo , Femenino , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Extractos Vegetales/aislamiento & purificación , Poli(ADP-Ribosa) Polimerasas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Chin Med J (Engl) ; 124(1): 84-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21362313

RESUMEN

BACKGROUND: Angelman syndrome (AS) is a neurogenetic disorder caused by an expression defect of the maternally inherited copy of ubiquitin protein ligase E3A (UBE3A) gene from chromosome 15. Although the most common genetic defects include maternal deletions of chromosome 15q11-13, paternal uniparental disomy and imprinting defect, mutations in the UBE3A gene have been identified in approximately 10% of AS patients. METHODS: A Chinese girl of 28 months presented clinical manifestation of AS. Genetic diagnosis and molecular genetic defects were studied by methylation-specific PCR (MS-PCR) and linkage analysis by short tandem repeat (STR). We further performed sequence analysis of all the coding exons and flanking sequences of the UBE3A gene. The novel mutation screening was also performed in 100 unrelated healthy individuals to exclude the possibility of identifying a polymorphism variation. RESULTS: The MS-PCR analysis of the patient showed biparental inheritance of chromosome 15 with a normal methylation pattern in the 15q11-q13 region. And STR analysis revealed that the patient also inherited biparental alleles for six microsatellites. A novel mutation, cDNA1199 C> A (p.P400H), in exon 9 of the maternal UBE3A gene, was identified in the patient. Meanwhile, the mutation was observed in the patient's mother who had a normal phenotype. CONCLUSIONS: It is necessary to perform the UBE3A gene mutation analysis in non-deletion/non-UPD/non-ID patients with AS. The clinical picture of the patient is concordant with that observed in previously reported AS patients with UBE3A mutation.


Asunto(s)
Mutación Missense/genética , Ubiquitina-Proteína Ligasas/genética , Síndrome de Angelman/genética , Preescolar , Cromosomas Humanos Par 15/genética , Femenino , Humanos , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa
17.
Cancer Lett ; 302(1): 69-75, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21216524

RESUMEN

The aim of this study was to determine the anticancer effects of seven licorice compounds in MKN-28, AGS, and MKN-45 gastric cancer cells and human gastric epithelium immortalized cells. We also explored the mechanism of action of licochalcone A (LCA), the most cytotoxic licorice compound, by analyzing its influence on cell cycle progression and apoptosis. The results indicated that LCA was the most cytotoxic licorice compound of those tested, and it inhibited gastric cancer cells growth in a dose-dependent manner, with an IC50 value of approximately 40µM. LCA affected gastric cancer cell viability by blocking cell cycle progression at the G2/M transition and inducing apoptosis. LCA treatment increased the expression of Rb and decreased the expression of cyclin A, cyclin B and MDM2 in MKN-28, AGS and MKN-45 cell lines. In addition, LCA-induced apoptosis by its effects on the expression of PARP, caspase-3, Bcl-2 and Bax. These data provide evidence that LCA has the potential to be used in the treatment of gastric cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Chalconas/farmacología , Proteínas Reguladoras de la Apoptosis/metabolismo , Western Blotting , Proteínas de Ciclo Celular/metabolismo , División Celular/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Chalconas/química , Relación Dosis-Respuesta a Droga , Fase G2/efectos de los fármacos , Glycyrrhiza/química , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología
18.
Zhonghua Er Ke Za Zhi ; 48(10): 783-6, 2010 Oct.
Artículo en Chino | MEDLINE | ID: mdl-21176491

RESUMEN

OBJECTIVE: To investigate the clinical manifestations and EEG characteristics of Angelman syndrome in children, and to strengthen the recognition of this disease. METHOD: Fourteen children with Angelman syndrome received video EEG monitoring, head MRI/CT and gene test, 11 patients received the metabolic investigations (e.g., lactic acid, ammonia, GC/MS and MS/MS). Eight patients received Gesell test. The patients were followed up for 1-3 years. RESULT: Of the 14 cases, 4 were male and 10 female, their age was from 8 months to 3 years and 7 months. The clinical characteristics included prominent lower jaw and wide mouth, fair skin and yellow hair, light-colored iris, paroxysmal laughter, astasia and language backward. Twelve patients had epileptic seizures; 10 patients displayed non-convulsive status epilepticus (NCSE), 9 patients displayed myoclonic, atypical absence, and non-convulsive seizure simultaneously; myoclonic, generalized tonic-clonic seizure and complex partial seizure in 1 each; 4 patients had fever in early seizures. The EEG showed paroxysmal middle-high amplitude 2-3 Hz spike and spinous slow-wave in 8 patients. Four patients showed paroxysmal frequently middle-high amplitude 2-3 Hz slow waves mixed with sharps. The other 2 patients showed a normal EEG. All the patients were diagnosed with genetics testing. The results included maternal deletion of chromosome 15q11-13 in 12, paternal uniparental disomy in 1 and imprinting defects in 1. CONCLUSION: There are characteristic clinical manifestation and craniofacial features in Angelman syndrome patients. Some patients have specific EEG patterns. Abnormal region of chromosome 15q11-13 is the basis of diagnosis.


Asunto(s)
Síndrome de Angelman/fisiopatología , Electroencefalografía , Síndrome de Angelman/diagnóstico , Síndrome de Angelman/genética , Preescolar , Femenino , Humanos , Lactante , Masculino
19.
Zhonghua Er Ke Za Zhi ; 48(12): 939-43, 2010 Dec.
Artículo en Chino | MEDLINE | ID: mdl-21215190

RESUMEN

OBJECTIVE: Angelman syndrome (AS) is a neurodevelopmental genetic disorder that maps to 15q11-13. The primary phenotypes are attributable to loss of expression of imprinted UBE3A gene within this region which can arise by means of a number of mechanisms. The purpose of this study was to make a genetic diagnosis and to analyze the clinical features in suspected patients with AS. METHOD: A total of 17 cases were diagnosed clinically as AS including 7 males and 10 females. The age at the time of diagnosis ranged from 8 months to 5 years. Genetic diagnosis was made by methylation-specific PCR (MS-PCR), linkage analysis by short tandem repeat (STR) and chromosome karyotype analysis. According to the international diagnostic criteria of AS, the related characteristic clinical features of the AS patients with deletion of 15q11-13 were analyzed and summarized. RESULT: Deletion of 15q11-13 was confirmed by genetic diagnosis in 17 AS patients. No abnormal findings were observed when they were born. Developmental delay in movement, speech impairments and happy disposition were observed in 100% (17/17) AS patients. And the severe speech deficit was much easier and more obvious to observe than movement. About 80% (14/17) - 90% (15/17) AS patients presented frequent clinical characteristics, such as seizures and abnormal EEG. However, microcephaly could only be observed in 35% (6/17) AS patients. Regarding the associated findings of AS, 41% (7/17) - 77% (13/17) AS patients could be observed with flat occiput/occipital groove, prognathia, wide mouth, wide-spaced teeth, frequent drooling, excessive mouth behaviors, hypopigmented skin, light hair compared to parents, flexed arm position during ambulation and sleep disorder etc. These features occurred at a higher frequency in those patients of > 2 years old group than that of < 2 years old group. CONCLUSION: The testing strategies of MS-PCR and STR linkage analysis combined with chromosome karyotype analysis were appropriate to the molecular genetic diagnosis of AS. In our analysis of clinical features, there was a lower rate of small head circumference (HC) in 35% patients compared with 80% patients in Caucasian with microcephaly, which might be attributable to the phenotypic heterogeneity in different races. And the birth history, movement and speech development and main clinical features of the Chinese AS patients were consistent with those of other studies. Clinical analysis in patients of different age groups showed that findings associated with AS would be more easily observed with the age increasing. Genetic diagnosis should be performed in clinically suspected AS patients.


Asunto(s)
Síndrome de Angelman/genética , Deleción Cromosómica , Cromosomas Humanos Par 15/genética , Síndrome de Angelman/diagnóstico , Preescolar , Femenino , Humanos , Lactante , Masculino , Fenotipo
20.
Zhonghua Er Ke Za Zhi ; 47(8): 604-7, 2009 Aug.
Artículo en Chino | MEDLINE | ID: mdl-19951494

RESUMEN

OBJECTIVE: To study the clinical and laboratory features of the patients with Menkes disease. METHOD: Three infants were diagnosed as Menkes disease. Their clinical feature, laboratory findings, radiological manifestation and genes were reviewed. RESULT: All the three cases were male infants. Their clinical manifestations began at the 3, 5 and 6 months after birth. They all had light complexion, sparse fuzzy woolly hair. The main clinical manifestation was severe mental retardation. The first and the third case also had focal clonus seizures. The second case had feeding difficulty after birth. Their hair showed pili torti and trichorrhexis nodosa microscopically. Their ceruloplasmin in plasma were 32.3 mg/L, 72.5 mg/L and 60.7 mg/L, which were significantly lower as compared with the normal values. Their neuroimaging findings were cortical atrophy, delayed myelination of the white matter and tortuosity of the intracranial vessels. The gene examination of the first and the second case showed deletion and nonsense mutation on exon 14 respectively. CONCLUSION: Menkes disease is an X-linked recessive disorder characterized by a copper-transporting ATPase defect. The main clinical manifestation is progressive nerve damage. Patients with the disease have special face and hair abnormality, and have morphological changes of brain blood vessels and cerebral atrophy.


Asunto(s)
Ceruloplasmina/análisis , Síndrome del Pelo Ensortijado/sangre , Síndrome del Pelo Ensortijado/diagnóstico , Técnicas de Laboratorio Clínico , Humanos , Lactante , Masculino
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