Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Biochem Genet ; 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38158465

RESUMEN

Bovine mastitis is a complex infectious disease that develops in the mammary gland, predominantly caused by a bacterial infection of mammary tissue. Genetic variability of mastitis is well established and depends upon different quantitative trait loci (QTL) related to mastitis resistance or susceptibility. The susceptibility is often attributed to single-nucleotide polymorphisms (SNPs) in the variable cow breed genomes. Several global investigative attempts have resulted in studies mapping mastitis to the variations in the relevant genes. Reports have been attributed to dramatic genetic expression changes in Toll-Like Receptor 4 (TLR4) genes in mastitis-positive cows. However, the mechanism behind this variable genetic expression of TLR4 genes has been studied poorly. The present study aims to investigate SCM through various screening tests like somatic cell count (SCC), electric conductivity (EC), pH, and California mastitis test (CMT) in milk samples. This study also aims to investigate possible mechanisms behind this variable expression of TLR4 by comparative SNP evaluation and transcriptional factor profile mining. So that the important genetic mutations and effects thereof can be exploited in selecting specific breeds with higher mastitis resistance and milk yield. Seventy Holstein Frisian (HF) crossbred dairy cows were selected in the present study. The animals were screened based on various diagnostic tests (SCC, pH, EC, and CMT). Blood samples (5 mL) were collected for extraction of DNA followed by amplification of PPR1 and PPR2 of the promoter region and 5'UTR of the bovine TLR4 gene using specific primers. Sanger's enzymatic DNA sequencing technique sequenced the amplified PCR products. Further, the identification of SNPs was done through various bioinformatic tools used in this study. The findings of the present study revealed that CMT, EC, pH, and SCC could be used for the early detection of subclinical mastitis. In the present study, a significant increase in the EC, pH, and SCC in milk samples of animals affected with SCM was found in comparison to the healthy animals. The present study also revealed 16 SNPs falling in TLR4 promoter and 5' untranslated region (5'UTR) sequences in mastitis-positive genotypes compared to reference genomes. The study also investigates the potential transcriptional factor program deployed in response to variable mastitis development resistance. In the present study, the allelic and genotype frequencies of all SNP variants in the three regions viz., PPR1, PPR2, and 5'UTR, were the same indicating the absence of heterozygous condition at the respective loci. The present study has wide applicability for researchers developing mastitis-resistant breeding programs and the data generated may aid in the selection of better genetic breeds. The transcription factor binding profiles can serve as concrete leads about the studies on bovine mastitis at the molecular level and may also aid global research groups working on transcription factor (TF)-based molecular pathology of mastitis.

2.
Sci Rep ; 12(1): 18726, 2022 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-36333409

RESUMEN

As the amount of data on farms grows, it is important to evaluate the potential of artificial intelligence for making farming predictions. Considering all this, this study was undertaken to evaluate various machine learning (ML) algorithms using 52-year data for sheep. Data preparation was done before analysis. Breeding values were estimated using Best Linear Unbiased Prediction. 12 ML algorithms were evaluated for their ability to predict the breeding values. The variance inflation factor for all features selected through principal component analysis (PCA) was 1. The correlation coefficients between true and predicted values for artificial neural networks, Bayesian ridge regression, classification and regression trees, gradient boosting algorithm, K nearest neighbours, multivariate adaptive regression splines (MARS) algorithm, polynomial regression, principal component regression (PCR), random forests, support vector machines, XGBoost algorithm were 0.852, 0.742, 0.869, 0.915, 0.781, 0.746, 0.742, 0.746, 0.917, 0.777, 0.915 respectively for breeding value prediction. Random forests had the highest correlation coefficients. Among the prediction equations generated using OLS, the highest coefficient of determination was 0.569. A total of 12 machine learning models were developed from the prediction of breeding values in sheep in the present study. It may be said that machine learning techniques can perform predictions with reasonable accuracies and can thus be viable alternatives to conventional strategies for breeding value prediction.


Asunto(s)
Algoritmos , Inteligencia Artificial , Ovinos/genética , Animales , Teorema de Bayes , Aprendizaje Automático , Redes Neurales de la Computación , Máquina de Vectores de Soporte
3.
Redox Rep ; 27(1): 92-99, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35435141

RESUMEN

Background: The cardiovascular crisis is advancing rapidly throughout the world. A large number of studies have shown that plant polyphenols affect major mechanisms involved in cardiovascular events through their action on the antioxidant system, signaling, and transcription pathways. D-limonene, a monocyclic monoterpene obtained from citrus fruits, is reported to possess many pharmacological activities.Methods: The experiment was designed to determine the protective effect of D-limonene against cardiac injury induced by CCl4 in Wistar rats. Rats were treated with two doses of D-limonene against cardiac injury induced by CCl4. Serum toxicity markers, cardiac toxicity biomarker enzymes, inflammatory mediators, anti-oxidant armory, lipid peroxidation, lipid profile, and histology were done.Results: CCl4 intoxication resulted in a substantial rise in FFA, TC, TG, PL, LDL, VLDL, and a reduction in HDL, restoring these changes with the administration of D-limonene at a dosage of 200 mg/kg. CCl4 administration also resulted in lipid oxidation and decreased antioxidant activity. At the same time, D-limonene at a dosage of 200 mg/kg body weight inhibited LPO and restored in vivo antioxidant components to normal. CCl4 intoxication also resulted in a significant increase in inflammatory markers like IL-6, TNF-α, high sensitivity Corticotropin Releasing Factor (Hs-CRF), and biomarkers of cardiac toxicity like alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase MB (CKMB), and Troponin I & troponin-t activities. D-limonene reversed all these changes to normal. Histology further confirmed our obtained results.Conclusion: These findings indicate that D-limonene can ameliorate cardiac injury at a 200 mg/kg body weight dosage. Henceforth, D-Limonene intervenes in mediating CCl4 induced toxicity by various signaling pathways.


Asunto(s)
Antioxidantes , Cardiotoxicidad , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Peso Corporal , Cardiotoxicidad/tratamiento farmacológico , Cardiotoxicidad/metabolismo , Creatina Quinasa/metabolismo , Creatina Quinasa/farmacología , Ciclohexanos , Limoneno/metabolismo , Limoneno/farmacología , Limoneno/uso terapéutico , Peroxidación de Lípido , Lípidos , Hígado , Estrés Oxidativo , Extractos Vegetales/farmacología , Ratas , Ratas Wistar
4.
Animals (Basel) ; 12(6)2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35327090

RESUMEN

Dairy cattle with a high milk yield are susceptible to many infectious diseases, such as mastitis. Subclinical mastitis (SCM) is the most prevalent form of mastitis that predominantly affects animal health, and causes adverse effects on the quality and quantity of milk. In dairy animals, subclinical mastitis often remains undetected, as no gross changes in udder characteristics are visible. In the present study, 135 Holstein Friesian dairy animals were selected and screened as healthy (n = 25) and mastitic (n = 110) based on diagnostic tests such as the California mastitis test, pH, electrical conductivity, and somatic cell count. In this study, the somatic cell count was used as a gold-standard test in differentiating subclinical mastitis animals from healthy ones. The present study was carried out to study polymorphisms in the bovine transferrin gene in cows (with subclinical mastitis and healthy). For the early detection of resistant/or susceptible animals, a useful marker could be provided by the detection of single-nucleotide polymorphisms (SNPs) in the transferrin gene, which are often associated with mammary innate immune response. The sequencing results revealed three nucleotide substitutions: two transversions (230 A > C, 231 C > A) and one transition (294 A > G) in susceptible cows as compared to disease-free subjects. The nucleotide variations at position 230 (GAC > GCA) and 231 (GAC > GCA) were nonsynonymous, and corresponded to an amino acid change from aspartic acid to alanine; whereas at position 294 (GAA > GAG), the mutation was synonymous. In the present study, many in silico tools were taken into consideration to determine the effect of SNPs on protein structure and function. The PROVEAN tool found the amino acid substitution to be neutral and deleterious. PolyPhen-2 revealed the amino acid variations at positions 320 and 321 to most likely be damaging; and at the 341 position, the variations were benign. The I-Mutant and MUpro tools found that the protein stability decreased for nonsynonymous variations. The SIFT tool revealed the protein function was likely to be affected in nonsynonymous variations, with no change in the case of synonymous ones. Phylogenetic analysis of the bovine transferrin gene revealed a close relation of the CA allele with the Bos taurus transferrin, while the G allele was closely related to a cross of Bos indicus × Bos taurus serotransferrins, followed by the Bison bison transferrin. The least relation was shown by both alleles to Capra hircus, Ovis aries, and Bubalus bubalis.

5.
J Food Biochem ; 45(3): e13241, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32515504

RESUMEN

Among the heavy metal poisonings, lead is considered as a major toxic metal causing hematological, neurological, immunological, hepatic, and renal dysfunctions. Lead causes inhibition of ALAD leading to the ALA accumulation inside the cells. Lead also leads to disruption of the anti-oxidative enzyme system, organ function, and lipid membranes of the cell causing oxidative stress. Zingerone, a phenolic alkanone, is an active edible ingredient present in the ginger that possess varied pharmacological properties. The aim of our study was to evaluate the protective effect of zingerone in lead-induced toxicity in wistar rats. ALAD concentration was improved in kidney and liver tissues treated with zingerone. Protective effect of zingerone was observed in terms of significant improvement in kidney and liver histology, anti-oxidant enzyme activity (CAT, SOD, GPx, and GR), organ function parameters, lipid profile, and decreased level of LPO. Therefore, zingerone pretreatment can be a promising agent for alleviation of lead-induced oxidative damage in cells. PRACTICAL APPLICATIONS: Published reports have revealed that consumption of certain bioactive nutrients for example, flavonoids, mineral elements, and vitamins can offer defense from the environmental lead contamination. Zingerone is a strong anti-oxidant, with very less side effects and has exceptional property of scavenging free radicals, hence reducing the oxidative stresses. This fundamental property of zingerone can alone help in countering the heavy metal toxicity. Different groups have published reported numerous properties of zingerone but as per our understanding till date no study about alleviation of lead toxicity by zingerone in animal model has been undertaken. Hence, we conducted this research to explore the preventive effect of zingerone in lead induced kidney and liver toxicity. The outcome of our study shows potent anti-oxidant effect and ALAD modulatory property of zingerone which makes it suitable edible candidate for use in countering lead toxicity.


Asunto(s)
Plomo , Estrés Oxidativo , Animales , Guayacol/análogos & derivados , Riñón/metabolismo , Plomo/toxicidad , Hígado/metabolismo , Ratas , Ratas Wistar
6.
Saudi Pharm J ; 26(8): 1137-1145, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30532634

RESUMEN

Diabetes is considered as the most common metabolic disease affecting millions of people all around the world. Use of natural herbal medicines can be effective in treating diabetes. Zingerone (4-(4-hydroxy-3-methylphenyl) butan-2-one) a polyphenolic alkanone extracted from ginger has a broad spectrum of pharmacological properties and thus can be used as a promising candidate against various ailments. In the current study we aimed at demonstrating the protective effect of zingerone against diabetes mellitus and elucidating its possible mechanism. Five groups of animals (I-V) were made with ten animals each. Group I (control) was given normal saline orally. Group II (diabetic positive control) was given alloxan at the dose rate of 100 mg/kg bwt once. Group III and IV was given alloxan once at the dose rate of 100 mg/kg bwt. and received oral treatment of zingerone at a dose rate of 50 and 100 mg/kg bwt respectively daily for 21 days. Group V was given alloxan at the dose of 100 mg/kg bwt. and was treated with standard drug glibenclamide at the dose rate of 4.5 mg/kg bwt. daily for 21 days. According to our findings we confirmed that zingerone restrained the alloxan induced oxidative stress by increasing the activity of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and reducing the peroxidative damage. We also confirmed that zingerone suppressed the level of redox sensitive transcription factor NFκB and downregulated other downstream inflammatory cytokines like interleukins (IL1-ß IL-2, IL-6) and tumor necrosis factor alpha (TNF-α). Moreover, the experimental findings suggested that zingerone improved the insulin levels. Taken together our results indicated that zingerone effectively ameliorated the diabetes induced complications which provide a strong theoretical basis for zingerone to be used clinically for treatment of diabetes.

7.
Environ Toxicol ; 33(4): 422-435, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29345053

RESUMEN

Colon cancer is a world-wide health problem and one of the most dangerous type of cancer, affecting both men and women. Naringenin (4, 5, 7-trihydroxyflavanone) is one of the major flavone glycoside present in citrus fruits. Naringenin has long been used in Chinese's traditional medicine because of its exceptional pharmacological properties and non-toxic nature. In the present study, we investigated the chemopreventive potential of Naringenin against 1,2-dimethyhydrazine (DMH)-induced precancerous lesions, that is, aberrant crypt foci (ACF) and mucin depleted foci (MDF), and its role in regulating the oxidative stress, inflammation and hyperproliferation, in the colon of Wistar rats. Animals were divided into five groups. In groups 3-5, Naringenin was administered at the dose of 50 mg/kg b. wt. orally while in groups 2-4, DMH was administered subcutaneously in the groin at the dose of 20 mg/kg b. wt. once a week for first 5 weeks and animals were euthanized after 10 weeks. Administration of Naringenin ameliorated the development of DMH-induced lipid peroxidation, ROS formation, precancerous lesions (ACF and MDF) and it also reduced the infiltration of mast cells, suppressed the immunostaining of NF-κB-p65, COX-2, i-NOS PCNA and Ki 67 Naringenin treatment significantly attenuated the level of TNF-α and it also prevented the depletion of the mucous layer. Our findings suggest that Naringenin has strong chemopreventive potential against DMH-induced colon carcinogenesis but further studies are warranted to elucidate the precise mechanism of action of Naringenin.


Asunto(s)
Anticarcinógenos/uso terapéutico , Neoplasias del Colon/prevención & control , Flavanonas/uso terapéutico , Lesiones Precancerosas/prevención & control , Focos de Criptas Aberrantes/patología , Focos de Criptas Aberrantes/prevención & control , Animales , Carcinogénesis/metabolismo , Carcinogénesis/patología , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/patología , Inflamación/metabolismo , Inflamación/prevención & control , Peroxidación de Lípido , Masculino , Mucinas/metabolismo , FN-kappa B/metabolismo , Estrés Oxidativo , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología , Ratas Wistar , Factor de Necrosis Tumoral alfa/metabolismo
8.
Environ Toxicol ; 33(3): 361-369, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29251412

RESUMEN

This study was designed to assess the potential antifibrotic effect of D-Limonene-a component of volatile oils extracted from citrus plants. D-limonene is reported to have numerous therapeutic properties. CCl4 -intduced model of liver fibrosis in Wistar rats is most widely used model to study chemopreventive studies. CCl4 -intoxication significantly increased serum aminotransferases and total cholesterol these effects were prevented by cotreatment with D-Limonene. Also, CCl4 -intoxication caused depletion of glutathione and other antioxidant enzymes while D-Limonene preserved them within normal values. Hydroxyproline and malondialdehyde content was increased markedly by CCl4 treatment while D-Limonene prevented these alterations. Levels of TNF-α, TGF-ß, and α-SMA were also assessed; CCl4 increased the expression of α-SMA, NF-κB and other downstream inflammatory cascade while D-Limonene co-treatment inhibited them. Collectively these findings indicate that D-Limonene possesses potent antifibrotic effect which may be attributed to its antioxidant and anti-inflammatory properties.


Asunto(s)
Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Ciclohexenos/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Terpenos/uso terapéutico , Animales , Tetracloruro de Carbono , Glutatión/metabolismo , Limoneno , Hígado/efectos de los fármacos , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/metabolismo , Masculino , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar , Factor de Crecimiento Transformador beta/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
9.
ScientificWorldJournal ; 2015: 816364, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26106644

RESUMEN

Humans have been using natural products for medicinal use for ages. Natural products of therapeutic importance are compounds derived from plants, animals, or any microorganism. Ginger is also one of the most commonly used condiments and a natural drug in vogue. It is a traditional medicine, having some active ingredients used for the treatment of numerous diseases. During recent research on ginger, various ingredients like zingerone, shogaol, and paradol have been obtained from it. Zingerone (4-(4-hydroxy-3-methoxyphenyl)-2-butanone) is a nontoxic and inexpensive compound with varied pharmacological activities. It is the least pungent component of Zingiber officinale. Zingerone is absent in fresh ginger but cooking or heating transforms gingerol to zingerone. Zingerone closely related to vanillin from vanilla and eugenol from clove. Zingerone has potent anti-inflammatory, antidiabetic, antilipolytic, antidiarrhoeic, antispasmodic, and so forth properties. Besides, it displays the property of enhancing growth and immune stimulation. It behaves as appetite stimulant, anxiolytic, antithrombotic, radiation protective, and antimicrobial. Also, it inhibits the reactive nitrogen species which are important in causing Alzheimer's disease and many other disorders. This review is written to shed light on the various pharmacological properties of zingerone and its role in alleviating numerous human and animal diseases.


Asunto(s)
Guayacol/análogos & derivados , Extractos Vegetales/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antidiarreicos/química , Antidiarreicos/farmacología , Antidiarreicos/uso terapéutico , Antieméticos , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Zingiber officinale/química , Guayacol/química , Guayacol/farmacología , Guayacol/uso terapéutico , Humanos , Lipólisis/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Protectores contra Radiación/química , Protectores contra Radiación/farmacología , Protectores contra Radiación/uso terapéutico
10.
J Exp Med ; 210(7): 1369-87, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23752229

RESUMEN

Human papillomavirus type 16 (HPV16) and other oncogenic viruses have been reported to deregulate immunity by suppressing the function of the double-stranded DNA innate sensor TLR9. However, the mechanisms leading to these events remain to be elucidated. We show that infection of human epithelial cells with HPV16 promotes the formation of an inhibitory transcriptional complex containing NF-κBp50-p65 and ERα induced by the E7 oncoprotein. The E7-mediated transcriptional complex also recruited the histone demethylase JARID1B and histone deacetylase HDAC1. The entire complex bound to a specific region on the TLR9 promoter, which resulted in decreased methylation and acetylation of histones upstream of the TLR9 transcriptional start site. The involvement of NF-κB and ERα in the TLR9 down-regulation by HPV16 E7 was fully confirmed in cervical tissues from human patients. Importantly, we present evidence that the HPV16-induced TLR9 down-regulation affects the interferon response which negatively regulates viral infection. Our studies highlight a novel HPV16-mediated mechanism that combines epigenetic and transcriptional events to suppress a key innate immune sensor.


Asunto(s)
Papillomavirus Humano 16/inmunología , Papillomavirus Humano 16/patogenicidad , Proteínas E7 de Papillomavirus/inmunología , Receptor Toll-Like 9/genética , Secuencia de Bases , Línea Celular Tumoral , Cuello del Útero/inmunología , Cuello del Útero/metabolismo , Cuello del Útero/virología , Regulación hacia Abajo/genética , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/virología , Femenino , Células HEK293 , Células HeLa , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Datos de Secuencia Molecular , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Regiones Promotoras Genéticas , Proteínas Represoras/metabolismo
11.
Asian Pac J Cancer Prev ; 13(1): 181-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22502664

RESUMEN

The aim of this study was to evaluate the methylation status of three important cancer related genes viz. p16, E-cadherin and hMLH1 promoters and to associate the findings with specific dietary habits in Kashmiris, a culturally distinct population in India, with gastric cancer. The study subjects were divided into three age groups viz. 0-30 yrs (1st), 31-60 yrs (2nd) and 61-90 yrs (3rd). A highly significant association between the intake of local hot salted tea in 2nd (p=0.001) and 3rd (p=0.009) age groups was observed with the promoter hypermethylation of E cadherin. Again a highly significant association between the aberrant methylation of hMLH1 (p=0.000) and p16 (p=0.000) promoters and the intake of local hot salted tea was observed in the 2nd age group of gastric cancer patients. The intake of sun-dried food was also significantly associated with the promoter hypermethylation of E cadherin (p=0.003) and p16 (p=0.015) genes in 3rd age group. The results of the present study suggest a close association between the aberrant methylation of p16, E-cadherin and hMLH1 promoters and the intake of local hot salted tea and sun-dried foods in Kashmiri population.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Cadherinas/genética , Metilación de ADN , Alimentos en Conserva , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Regiones Promotoras Genéticas/genética , Neoplasias Gástricas/genética , , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Islas de CpG/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina , ADN de Neoplasias/genética , Femenino , Calor , Humanos , India/epidemiología , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Reacción en Cadena de la Polimerasa , Pronóstico , Neoplasias Gástricas/epidemiología , Luz Solar , Adulto Joven
12.
Int J Cancer ; 130(11): 2484-94, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21796618

RESUMEN

The DOK1 gene is a putative tumour suppressor gene located on the human chromosome 2p13 which is frequently rearranged in leukaemia and other human tumours. We previously reported that the DOK1 gene can be mutated and its expression down-regulated in human malignancies. However, the mechanism underlying DOK1 silencing remains largely unknown. We show here that unscheduled silencing of DOK1 expression through aberrant hypermethylation is a frequent event in a variety of human malignancies. DOK1 was found to be silenced in nine head and neck cancer (HNC) cell lines studied and DOK1 CpG hypermethylation correlated with loss of gene expression in these cells. DOK1 expression could be restored via demethylating treatment using 5-aza-2'deoxycytidine. In addition, transduction of cancer cell lines with DOK1 impaired their proliferation, consistent with the critical role of epigenetic silencing of DOK1 in the development and maintenance of malignant cells. We further observed that DOK1 hypermethylation occurs frequently in a variety of primary human neoplasm including solid tumours (93% in HNC, 81% in lung cancer) and haematopoietic malignancy (64% in Burkitt's lymphoma). Control blood samples and exfoliated mouth epithelial cells from healthy individuals showed a low level of DOK1 methylation, suggesting that DOK1 hypermethylation is a tumour specific event. Finally, an inverse correlation was observed between the level of DOK1 gene methylation and its expression in tumour and adjacent non tumour tissues. Thus, hypermethylation of DOK1 is a potentially critical event in human carcinogenesis, and may be a potential cancer biomarker and an attractive target for epigenetic-based therapy.


Asunto(s)
Metilación de ADN , Proteínas de Unión al ADN/genética , Neoplasias de Cabeza y Cuello/genética , Fosfoproteínas/genética , Regiones Promotoras Genéticas , Proteínas de Unión al ARN/genética , Adulto , Anciano , Azacitidina/análogos & derivados , Azacitidina/farmacología , Línea Celular Tumoral , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Proteínas de Unión al ADN/antagonistas & inhibidores , Decitabina , Femenino , Genes Supresores de Tumor , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Fosfoproteínas/antagonistas & inhibidores , Proteínas de Unión al ARN/antagonistas & inhibidores , Factores de Riesgo , Proteínas Supresoras de Tumor/genética
13.
J Virol ; 85(17): 9013-22, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21715489

RESUMEN

Constitutive activation of NF-κB signaling is a key event in virus- and non-virus-induced carcinogenesis. We have previously reported that cutaneous human papillomavirus type 38 (HPV38) displays transforming properties in in vitro and in vivo experimental models. However, the involvement of NF-κB signaling in HPV38-induced cell growth transformation remains to be determined. In this study, we showed that HPV38 E6 and E7 activate NF-κB and that inhibition of the pathway with the IκBα superrepressor sensitizes HPV38E6E7-immortalized human keratinocytes to tumor necrosis factor alpha (TNF-α)- and UVB radiation-mediated apoptosis. Accordingly, inhibition of NF-κB signaling resulted in the downregulation of NF-κB-regulated antiapoptotic genes, including cIAP1, cIAP2, and xIAP genes. These findings demonstrate a critical role of NF-κB activity in the survival of HPV38E6E7-immortalized human keratinocytes exposed to cytokine or UV radiation. Our data provide additional evidence for cooperation between beta HPV infection and UV irradiation in skin carcinogenesis.


Asunto(s)
Apoptosis , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , FN-kappa B/metabolismo , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/patogenicidad , Factor de Necrosis Tumoral alfa/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Humanos
14.
J Virol ; 85(17): 8477-94, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21697493

RESUMEN

We previously reported that the oncoproteins E6 and E7 from cutaneous human papillomavirus type 38 (HPV38) can immortalize primary human keratinocytes in vitro and sensitize transgenic mice to develop skin cancer in vivo. Immunofluorescence staining revealed that human keratinocytes immortalized by HPV38 E6 and E7 display fewer actin stress fibers than do control primary keratinocyte cells, raising the possibility of a role of the viral oncoproteins in the remodeling of the actin cytoskeleton. In this study, we show that HPV38 E7 induces actin stress fiber disruption and that this phenomenon correlates with its ability to downregulate Rho activity. The downregulation of Rho activity by HPV38 E7 is mediated through the activation of the CK2-MEK-extracellular signal-regulated kinase (ERK) pathway. In addition, HPV38 E7 is able to induce actin fiber disruption by binding directly to eukaryotic elongation factor 1A (eEF1A) and abolishing its effects on actin fiber formation. Finally, we found that the downregulation of Rho activity by HPV38 E7 through the CK2-MEK-ERK pathway facilitates cell growth proliferation. Taken together, our data support the conclusion that HPV38 E7 promotes keratinocyte proliferation in part by negatively regulating actin cytoskeleton fiber formation through the CK2-MEK-ERK-Rho pathway and by binding to eEF1A and inhibiting its effects on actin cytoskeleton remodeling.


Asunto(s)
Actinas/metabolismo , Quinasa de la Caseína II/metabolismo , Citoesqueleto/metabolismo , Factor 1 Eucariótico de Iniciación/antagonistas & inhibidores , Queratinocitos/virología , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/patogenicidad , Línea Celular , Proliferación Celular , Humanos , Unión Proteica
15.
Mol Cell Biol ; 31(11): 2210-26, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21482671

RESUMEN

ΔNp73α, a dominant-negative inhibitor of p53 and p73, exhibits antiapoptotic and transforming activity in in vitro models and is often found to be upregulated in human cancers. The mechanisms involved in the regulation of ΔNp73α protein levels in normal and cancer cells are poorly characterized. Here, we show that that IκB kinase beta (IKKß) increases ΔNp73α protein stability independently of its ability to activate NF-κB. IKKß associates with and phosphorylates ΔNp73α at serine 422 (S422), leading to its accumulation in the nucleus, where it binds and represses several p53-regulated genes. S422A mutation in ΔNp73α abolished IKKß-mediated stabilization and inhibition of p53-regulated gene expression. Inhibition of IKKß activity by chemical inhibitors, overexpression of dominant-negative mutants, or gene silencing by siRNA also resulted in ΔNp73α destabilization, which under these conditions was rapidly translocated into the cytoplasm and degraded by a calpain-mediated mechanism. We also present evidence for the IKKß and ΔNp73α cross talk in cancer-derived cell lines and primary cancers. Our data unveil a new mechanism involved in the regulation of the p73 and p53 network.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Quinasa I-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Células Cultivadas , Proteínas de Unión al ADN/genética , Expresión Génica , Células HEK293 , Humanos , Immunoblotting , Inmunoprecipitación , Ratones , Mutación , FN-kappa B/metabolismo , Proteínas Nucleares/genética , Fosforilación , Estabilidad Proteica , Interferencia de ARN , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serina/metabolismo , Transcripción Genética , Proteína Tumoral p73 , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor/genética
16.
Int J Cancer ; 128(5): 1104-13, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20473930

RESUMEN

NK cell recognition of tumor cells is mediated by a delicate balance of signals received by MHC class I-binding inhibitory NK cell receptors and activating NK cell receptors, which mainly bind to virus-, stress- or tumor-induced ligands. In addition, adhesion molecules such as the intercellular adhesion molecule-1 (ICAM-1) and its receptors, the lymphocyte function-associated antigen-1 (LFA-1) and Mac-1, are crucial for immune synapse formation and NK cell-mediated killing. In this study, we show that expression of the adhesion molecule ICAM-1 was rapidly induced by E6 and -E7 oncoproteins of HPV16, -18, -5 and -8, but not of HPV38 and -6 in primary human keratinocytes after retroviral transduction. ICAM-1 was upregulated in E6E7-expressing keratinocytes both at mRNA and protein levels. The observed ICAM-1 upregulation in HPV16-E6E7-expressing keratinocytes was partially dependent on activation of the NF-κB pathway. Importantly, the upregulated ICAM-1 expression in HPV16-E6E7-expressing keratinocytes led to enhanced conjugate formation with NK cells. We previously showed that HPV16-positive cervical carcinomas frequently express low levels of inhibitory NK cell ligands and high levels of activating NK cell ligands. Moreover, levels of the adhesion molecule ICAM-1 are enhanced by HPV16-E6/E7. Therefore, strategies that aim at harnessing NK cells might be beneficial for the treatment of cervical carcinoma.


Asunto(s)
Molécula 1 de Adhesión Intercelular/fisiología , FN-kappa B/fisiología , Proteínas Oncogénicas Virales/fisiología , Proteínas E7 de Papillomavirus/fisiología , Proteínas Represoras/fisiología , Regulación hacia Arriba/fisiología , Secuencia de Bases , Western Blotting , Células Cultivadas , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Queratinocitos/citología , Queratinocitos/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Mutat Res ; 676(1-2): 5-10, 2009 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-19486858

RESUMEN

Kangri cancer is a unique, thermally induced squamous cell carcinoma (SCC) of the skin that develops due to persistent use of a Kangri (a brazier) by the Kashmiri people to combat the cold temperature during winter. Unlike classical UV-induced SCC of the skin, Kangri cancer appears on the legs and abdomen. Its common features are erythematous patches, recurrence and metastasis. In the absence of any molecular etiology, we made a preliminary attempt to estimate the nature and frequency of mutations in the TP53 and PTEN genes in Kangri cancer patients from Kashmir. PCR-SSCP analysis followed by direct sequencing revealed that TP53 mutations account for 40% (12/30) of sporadic Kangri cancer patients and that PTEN mutations account for only 6.6% (2/30). There were 16 mutations in TP53 exons 5 and 7, found in 12 patients. They consisted of 11 substitutions (7 transitions, 3 transversions and 1 double-base) and 5 insertions. The 11 substitutions represent 8 distinct missense mutations, 3 of which were silent mutations. The mutations detected in the PTEN gene consisted of one insertion and one C>T transition. This high percentage of TP53 mutations (especially A>G) showed a statistically significant association with age and positive lymph node status. Our results indicate that TP53 is a predominant target of chronic hyperthermia in the development of Kangri cancer in the moderate risk Kashmiri population. The differences in the TP53 mutation spectrum of UV-induced SCC of the skin and Kangri cancer are probably due to the nature of the respective environmental carcinogens. The study also suggests that TP53 may function as a potential molecular marker and prognostic tool, at least in a subset of sporadic Kangri tumors.


Asunto(s)
Carcinoma de Células Escamosas/genética , Predisposición Genética a la Enfermedad , Fosfohidrolasa PTEN/genética , Grupos de Población/genética , Neoplasias Cutáneas/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Secuencia Conservada/genética , Análisis Mutacional de ADN , Etnicidad , Exones/genética , Femenino , Frecuencia de los Genes , Genes BRCA1 , Humanos , India/etnología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple
18.
Cancer Lett ; 248(2): 308-20, 2007 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-16996204

RESUMEN

Breast cancer shows geographical variation in its incidence, even within areas of ethnic homogeneity. Kashmir valley (India), over past few years, witnesses an increase in incidence and occurrence of familial, early onset, and male breast cancer in its unexplored ethnic population. Here, we make a preliminary attempt to estimate the nature and frequency of BRCA1 and TP53 gene mutations of breast cancer patients from Kashmir. PCR-SSCP analysis followed by direct sequencing revealed the presence of only two germline intronic variations (c.199+67T>C and c.5396+187T>C) in BRCA1 gene in only 5.26% (2/38) patients while as 44% (11/25) of sporadic breast cancer patients harboured significant amount of somatic mutations in TP53 (p=0.0074; OR=0.053). The 17 mutations found in TP53 in 11 patients, comprised of 13 substitutions [11 single-base (9 transitions+2 transversions), 1 double-base and 1 complex] and four insertions. The 11 substitutions represent missense mutations, leading to aminoacid substitution while as rest two were silent mutations. The four insertions represented three frame-shifts and one non-sense mutation. The mutation effect data was found to be significant (p=0.0002). Significant amount of mutations were found in exon 6 (p=0.04; OR=0.273) and a combination of exons 6 and 7 (p=0.0145; OR=14.22) of TP53. Comparison of mutation profile with other ethnic populations and regions reflected both differences and similarities indicating co-exposure to a unique set of risk factors. The differences could be due to exposure to particular environmental carcinogens; different lifestyle, reproductive pattern; dietary or cultural practices of Kashmiri women that need further investigations. The infrequent presence of germline BRCA1 mutations in our study agree with the idea that a great proportion of moderate risk breast cancer population could be due to the susceptibility genes distinct from BRCA1. However, high frequency of somatic TP53 gene mutations implicates TP53 as a predominant factor for breast carcinogenesis in moderate risk ethnic Kashmiri population. The study also suggests TP53 as a potential molecular marker and prognostic tool, at least in a subset of sporadic breast tumors.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Genes BRCA1 , Genes p53 , Predisposición Genética a la Enfermedad , Adulto , Anciano , Secuencia de Bases , Análisis Mutacional de ADN , Femenino , Humanos , India , Persona de Mediana Edad , Mutación , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Factores de Riesgo
19.
Indian J Clin Biochem ; 21(2): 76-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23105619

RESUMEN

Pleural effusion is one of the commonest presentations of tuberculosis, the clinical manifestations being typically abrupt resembling bacterial pneumonia. Since delayed hypersensitivity is the underlying immune response, bacterial load is very low. Owing to these facts, tuberculous pleurisy as an extra-pulmonary disease poses a diagnostic dilemma. The conventional bacteriological methods rarely detect Mycobacterium tuberculosis in pleural fluid and are of limited use in diagnosis of tuberculous pleurisy. We evaluated the efficacy of polymerase chain reaction (PCR) in the diagnosis of tuberculous pleurisy by targeting the gene segment coding for MPB64 protein specific forMycobacterium tuberculosis. Based on the clinical criteria, 82 patients with lymphocytic exudative pleural effusion were included in the study. Patients were analyzed in two groups; one group consisting of 48 patients of tubercular pleural effusion confimed by various diagnostic procedures and another group of 34 patients comprising of non-tubercular pleural effusion. There were no false positive results by PCR and the specificity worked out to be 100%. Twenty two patients tested positive for Mantoux with a sensitivity of 45%. ZN-staining for AFB was found in samples from 15 patients (20% sensitivity). ADA was positive for 28 patients with a sensitivity of 53%. PCR was positive for 32/48 patients (67% sensitivity). Thus, PCR was found to be more sensitive than any other conventional method in diagnosis of clinically suspected tubercular pleurisy.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...