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1.
bioRxiv ; 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37905122

RESUMEN

Among the numerous changes associated with the transformation to cancer, cellular metabolism is one of the first discovered and most prominent[1, 2]. However, despite the knowledge that nearly every cancer is associated with the strong upregulation of various metabolic pathways, there has yet to be much clinical progress on the treatment of cancer by targeting a single metabolic enzyme directly[3-6]. We previously showed that inhibition of glycolysis through lactate dehydrogenase (LDHA) deletion in cancer cells of origin had no effect on the initiation or progression of cutaneous squamous cell carcinoma[7], suggesting that these cancers are metabolically flexible enough to produce the necessary metabolites required for sustained growth in the absence of glycolysis. Here we focused on glutaminolysis, another metabolic pathway frequently implicated as important for tumorigenesis in correlative studies. We genetically blocked glutaminolysis through glutaminase (GLS) deletion in cancer cells of origin, and found that this had little effect on tumorigenesis, similar to what we previously showed for blocking glycolysis. Tumors with genetic deletion of glutaminolysis instead upregulated lactate consumption and utilization for the TCA cycle, providing further evidence of metabolic flexibility. We also found that the metabolic flexibility observed upon inhibition of glycolysis or glutaminolysis is due to post-transcriptional changes in the levels of plasma membrane lactate and glutamine transporters. To define the limits of metabolic flexibility in cancer initiating hair follicle stem cells, we genetically blocked both glycolysis and glutaminolysis simultaneously and found that frank carcinoma was not compatible with abrogation of both of these carbon utilization pathways. These data point towards metabolic flexibility mediated by regulation of nutrient consumption, and suggest that treatment of cancer through metabolic manipulation will require multiple interventions on distinct pathways.

3.
Sci Rep ; 11(1): 23618, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34880273

RESUMEN

Humpback whales (Megaptera novaeangliae) are a cosmopolitan species and perform long annual migrations between low-latitude breeding areas and high-latitude feeding areas. Their breeding populations appear to be spatially and genetically segregated due to long-term, maternally inherited fidelity to natal breeding areas. In the Southern Hemisphere, some humpback whale breeding populations mix in Southern Ocean waters in summer, but very little movement between Pacific and Atlantic waters has been identified to date, suggesting these waters constituted an oceanic boundary between genetically distinct populations. Here, we present new evidence of summer co-occurrence in the West Antarctic Peninsula feeding area of two recovering humpback whale breeding populations from the Atlantic (Brazil) and Pacific (Central and South America). As humpback whale populations recover, observations like this point to the need to revise our perceptions of boundaries between stocks, particularly on high latitude feeding grounds. We suggest that this "Southern Ocean Exchange" may become more frequent as populations recover from commercial whaling and climate change modifies environmental dynamics and humpback whale prey availability.


Asunto(s)
Yubarta/fisiología , Reproducción , Migración Animal , Animales , Cambio Climático , Conducta Alimentaria , Océanos y Mares
4.
Med Oral Patol Oral Cir Bucal ; 26(4): e541-e548, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34162824

RESUMEN

BACKGROUND: Patients with oral lichen planus (OLP) have an increased risk of oral cancer. For this reason, OLP is classified as an oral potentially malignant disorder. However, the precise personal (or individual) risk is unknown. Recent meta-analytical studies have reported that dysplastic OLP may transform to cancer in around 6% of cases, while the rate of transformation is lower (<1.5%) in non-dysplastic cases. The presence of epithelial dysplasia has emerged as the most powerful indicator for assessing cancer risk in oral potentially malignant disorders in routine practice. However, the general acceptance of epithelial dysplasia as an accompanying histologic feature in OLP is subject to great controversy. Many pathologists consider the presence of dysplasia as a criterion to exclude OLP when routinely reporting on this disease. This practice, widespread among oral pathology professionals, has resulted in the underestimation of the potential for malignancy of OLP. MATERIAL AND METHODS: A review of the literature was carried out in order to critically analyze the relevance, controversies and challenges encountered across the diagnosis of epithelial dysplasia in OLP. RESULTS: 12 studies have been published examining dysplastic changes in OLP, reporting figures ranging from 0.54% to 25% of cases with dysplasia in the first diagnostic biopsy. The diagnosis of dysplasia in the OLP poses an additional difficulty due to the fact that the affected oral epithelium per se develops changes related to autoimmune aggression. Among the most frequent histological features of OLP that develops dysplasia are basal cell hyperplasia with basaloid appearance, loss of basal cells polarity, cellular and nuclear pleomorphism and irregular stratification. CONCLUSIONS: Epithelial dysplasia should not be considered an exclusion criterion for OLP; its evaluation requires experienced pathologists in this field.


Asunto(s)
Liquen Plano Oral , Enfermedades de la Boca , Neoplasias de la Boca , Biopsia , Transformación Celular Neoplásica , Humanos , Hiperplasia , Liquen Plano Oral/complicaciones
5.
Lett Appl Microbiol ; 71(3): 280-286, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32408383

RESUMEN

In this study, the prevalence of Vibrio cholerae, Vibrio parahaemolyticus, Vibrio mimicus, Vibrio vulnificus and Vibrio spp. in shrimp from retail markets in Reynosa, Mexico was determined. A total of 765 isolates, identified as Vibrio spp. (59·1%), V. cholerae (17·8%), V. mimicus (6·7%) and V. parahaemolyticus (4·6%), were obtained; V. vulnificus was not detected. Most of the strains were isolated from supermarkets (48·1%), followed by street vendors (37·3%) and retail stores (14·6%). Moreover, several virulence genes were identified in V. cholerae: toxR (100%), OmpU (76·5%), hlyA (76·5%), VPI (19·9%) and tcpA (5·1%); in V. mimicus: vmh (100%), wzb (74·5%), pilF (54·9%), VPI (43·1%), OmpU (29·4%) and tdh (9·8%); and in V. parahaemolyticus: toxR (100%), tlh (100%), VP1680 (51·4%) and VPI (11·4%). These results show the low safety of this food and the potential risk to consumers' health, since this product in Mexican cuisine is sometimes served raw or semi-cooked. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows the prevalence of pathogenic Vibrio cholerae, Vibrio mimicus and Vibrio parahaemolyticus isolated from shrimp that is commercialized in Reynosa city. This could represent a risk to consumers' health, since outbreaks related to shrimp contaminated with Vibrio have been previously reported. Additionally, shrimp fishing has a major role in Mexico's economy.


Asunto(s)
Penaeidae/microbiología , Alimentos Marinos/microbiología , Vibrio cholerae/aislamiento & purificación , Vibrio mimicus/aislamiento & purificación , Vibrio parahaemolyticus/aislamiento & purificación , Vibrio vulnificus/aislamiento & purificación , Animales , Contaminación de Alimentos/análisis , Inocuidad de los Alimentos , México , Prevalencia , Alimentos Crudos/microbiología , Supermercados , Virulencia/genética
6.
Lett Appl Microbiol ; 67(2): 190-196, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29791974

RESUMEN

The Rio Bravo (Rio Grande) adjoins various states in the Mexican region and has a great importance in water distribution in the northeast Tamaulipas (Mexico). In this work 161 strains were isolated, identified and characterized from the water samples taken from the flow of the Rio Bravo and the two inner canals that cover Reynosa city. The strains were identified as Vibrio cholerae (74·5%), Vibrio spp. (1·2%) and Vibrio mimicus (0·6%). Furthermore, the detected virulence genes in the V. cholerae strains, were the hlyA, ompU, tcpA, toxR genes in 78·3, 62·5, 15·8 and 90·8% respectively. Only the ompU and vmh genes were detected in the V. mimicus strain. These results indicate the presence of multi-toxigenic V. cholerae strains in the Rio Bravo/Grande and in the water bodies from Reynosa city, which could represent a risk for the exposed population. SIGNIFICANCE AND IMPACT OF THE STUDY: Water quality is associated with public health, as it plays an important role in the transmission and epidemiology of pathogens such as Vibrio, since this species have been responsible for human diseases around the world. This study demonstrated the presence of toxigenic Vibrio species in water bodies in Reynosa surroundings, indicating that water bodies may be a source of public health risk.


Asunto(s)
Ríos/microbiología , Vibrio cholerae , Adhesinas Bacterianas/genética , Proteínas Bacterianas/genética , Proteínas de Unión al ADN/genética , Proteínas Fimbrias/genética , Proteínas Hemolisinas/genética , Humanos , México , Nitrilos , Serogrupo , Factores de Transcripción/genética , Vibrio cholerae/clasificación , Vibrio cholerae/genética , Vibrio cholerae/aislamiento & purificación , Vibrio cholerae/patogenicidad , Virulencia/genética , Microbiología del Agua
7.
J Oral Pathol Med ; 46(2): 148-153, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27426232

RESUMEN

BACKGROUND: Oral lichen planus (OLP) and oral lichenoid lesions (OLL) are considered potentially malignant disorders with a cancer incidence of around 1% of cases, although this estimation is controversial. The aim of this study was to analyze the cancer incidence in a case series of patients with OLP and OLL and to explore clinicopathological aspects that may cause underestimation of the cancer incidence in these diseases. METHODS: A retrospective study was conducted of 102 patients diagnosed with OLP (n = 21, 20.58%) or OLL (n = 81) between January 2006 and January 2016. Patients were informed of the risk of malignization and followed up annually. The number of sessions programmed for each patient was compared with the number actually attended. Follow-up was classified as complete (100% attendance), good (75-99%), moderate (25-74%), or poor (<25% attendance) compliance. RESULTS: Cancer was developed by four patients (3.9%), three males and one male. One of these developed three carcinomas, which were diagnosed at the follow-up visit (two in lower gingiva, one in floor of mouth); one had OLL and the other three had OLP. The carcinoma developed in mucosal areas with no OLP or OLL involvement in three of these patients, while OLP and cancer were diagnosed simultaneously in the fourth. Of the six carcinomas diagnosed, five (83.3%) were T1 and one (16.7%) T2. None were N+, and all patients remain alive and disease-free. CONCLUSIONS: The cancer incidence in OLP and OLL appears to be underestimated due to the strict exclusion criteria usually imposed.


Asunto(s)
Liquen Plano Oral/complicaciones , Erupciones Liquenoides/complicaciones , Neoplasias de la Boca/etiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/epidemiología
8.
J Eur Acad Dermatol Venereol ; 30(8): 1315-20, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27291154

RESUMEN

BACKGROUND: There is inadequate knowledge on the involvement of oncogenic mechanisms linked to the cyclin (CCND1) gene in lip squamous cell carcinoma (LSCC). OBJECTIVE: The aim of this study was to analyse the implication of cyclin D1 in the malignant transformation of lip lesions. METHODS: We immunohistochemically studied 45 actinic cheilitis cases (15 mild dysplasia, 15 moderate dysplasia, 15 severe dysplasia/carcinoma in situ), 30 LSCC cases with adjacent non-tumour epithelium and 15 normal oral epithelium samples for detection of cyclin D1, ß-catenin and Ki-67. RESULTS: Cyclin D1 and Ki-67 expressions were significantly increased in the basal layer of premalignant epithelia and peripheral layers of tumour nests vs. CONTROLS: Premalignant epithelia had lost their asymmetrical proliferative pattern. CONCLUSION: Lip carcinogenesis was associated with loss of the asymmetrical proliferative pattern, a preventive mechanism against lip oncogenesis, and with cyclin D1 overexpression.


Asunto(s)
Proliferación Celular , Ciclina D1/metabolismo , Neoplasias de los Labios/patología , Labio/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Labio/metabolismo , Neoplasias de los Labios/metabolismo , Masculino , Persona de Mediana Edad , Adulto Joven
9.
Immunol Lett ; 175: 40-3, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27178308

RESUMEN

STAT4 has been consistently associated with several autoimmune diseases, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The aim of this study was to determine whether the STAT4 rs7574865G/T polymorphism confers susceptibility for RA and SLE in a sample of Mexican patients. This study included 869 individuals: 415 patients with RA, 128 patients with SLE, and 326 controls. Genotyping using TaqMan probes showed an association between the STAT4 rs7574865G/T polymorphism and RA (GG vs. TT: OR 1.99, p=0.0009; G vs. T: OR 1.42, p=0.0009) and SLE (GG vs. TT: OR 2.98, 0.0003; G vs. T: OR 1.74, p=0.0002). Gender stratification showed an association with RA (GG vs. TT: OR 1.99, 95% CI 1.3-3.1, p=0.002; G vs. T: OR 1.42, 95% CI 1.1-1.8, p=0.002) and SLE (GG vs. TT: OR 3.3, 95% CI 1.7-6.2, p=0.0002; G vs. T: OR 1.8, 95% CI 1.3-2.4, p=0.0002) in women. Thus, the STAT4 rs7574865G/T polymorphism confers risk for RA and SLE in the Mexican population.


Asunto(s)
Artritis Reumatoide/genética , Lupus Eritematoso Sistémico/genética , Factor de Transcripción STAT4/genética , Adulto , Artritis Reumatoide/epidemiología , Análisis Mutacional de ADN , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Lupus Eritematoso Sistémico/epidemiología , Masculino , México/epidemiología , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Riesgo , Factores Sexuales
10.
Av. periodoncia implantol. oral ; 27(3): 117-124, dic. 2015. ilus
Artículo en Español | IBECS | ID: ibc-140270

RESUMEN

INTRODUCCIÓN: La cirugía guiada y la carga inmediata de los implantes constituye un nuevo enfoque integral de la rehabilitación de los pacientes edéntulos. El objetivo del presente trabajo era presentar el protocolo diagnóstico, quirúrgico y protésico del tratamiento con implantes mediante la técnica de cirugía guiada y carga inmediata en el tratamiento del maxilar edéntulo. CASO CLÍNICO: Paciente varón de 70 años que acude a consulta para tratamiento con implantes del maxilar edéntulo. La tomografía computarizada de haz cónico (TCHC) muestra que el paciente presenta un adecuado volumen óseo para la inserción de implantes. La información obtenida por la TCHC es utilizada para la evaluación y el plan de tratamiento. Se planificaron diez implantes. Los datos digitales de imagen tomográfica fueron enviados a un centro especializado (Galimplant 3.D(R)) para la realización de la férula quirúrgica y la prótesis provisional. De acuerdo a la férula guiada se insertaron los implantes sin colgajo con un fresado preciso. La prótesis fija inmediata provisional fue realizada y ajustada sobre los pilares, evaluando su oclusión. La prótesis fija definitiva se realizó después de un periodo de 6 meses. CONCLUSIONES: Este caso clínico indica que la implantología oral guiada puede constituir una terapéutica exitosa en el tratamiento del paciente edéntulo maxilar


INTRODUCTION: Guided surgery and immediate functional loading of dental implants constitute a new comprehensive approach for rehabilitation of edentulous patients. The aim of this paper was to present the diagnosis, surgical and prosthetic protocol of implants by guided technique and immediate loading in the treatment of edentulous maxilla. CASE REPORT: A 70-year-old-man, requested an evaluation regarding implant treatment for the edentulous maxilla. The cone beam computarized tomography (CBCT) showed that the patient have an adequate bone volume for maxillary implant placement. The data from CBCT were used for evaluation and treatment planning. Ten implants were treatment planned. Digital data were sent to a software manufacturer (Galimplant.3D(R)) and surgical template and fixed provisional prosthesis according clinical examination were received. According surgical template implants were inserted for a flapless surgical technique with an accuraced drilling. Immediate transitional fixed prosthesis were realized and adjusted with the abutment and finally, occlusion is evaluated. Definitive fixed prosthesis was realized after a 6 month-period of time. CONCLUSIONS: This paper indicated that guided implant dentistry may constitute a successful treatment of edentulous maxillary patients


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Implantes Dentales , Carga Inmediata del Implante Dental/instrumentación , Carga Inmediata del Implante Dental , Arcada Edéntula/rehabilitación , Arcada Edéntula/cirugía , Ibuprofeno/uso terapéutico , Clorhexidina/uso terapéutico , Implantación Dental/métodos , Cirugía Asistida por Computador , Protocolos Clínicos/normas , Consentimiento Informado/normas , Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Tomografía Computarizada de Haz Cónico
11.
Lett Appl Microbiol ; 61(4): 367-73, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26174059

RESUMEN

UNLABELLED: The fruit juice industry recognizes Alicyclobacillus as a major quality control target micro-organism. In this study, we analysed 19 bacterial isolates to identify Alicyclobacillus species by polymerase chain reaction (PCR) and sequencing analyses. Phenotypic and genomic diversity among isolates were investigated by API 50CHB system and ERIC-PCR (enterobacterial repetitive intergenic consensus-PCR) respectively. All bacterial isolates were identified as Alicyclobacillus acidocaldarius, and almost all showed identical DNA sequences according to their 16S rRNA (rDNA) gene partial sequences. Only few carbohydrates were fermented by A. acidocaldarius isolates, and there was little variability in the biochemical profile. Genotypic fingerprinting of the A. acidocaldarius isolates showed high diversity, and clusters by ERIC-PCR were distinct to those obtained from the 16S rRNA gene phylogenetic tree. There was no correlation between phenotypic and genotypic variability in the A. acidocaldarius isolates analysed in this study. SIGNIFICANCE AND IMPACT OF THE STUDY: Detection of Alicyclobacillus strains is imperative in fruit concentrates and juices due to the production of guaiacol. Identification of the genera originates rejection of the product by processing industry. However, not all the Alicyclobacillus species are deteriorative and hence the importance to differentiate among them. In this study, partial 16S ribosomal RNA sequence alignment allowed the differentiation of species. In addition, ERIC-PCR was introduced for the genotypic characterization of Alicyclobacillus, as an alternative for differentiation among isolates from the same species.


Asunto(s)
Alicyclobacillus/genética , Contaminación de Alimentos/análisis , Jugos de Frutas y Vegetales/microbiología , Frutas/microbiología , Tipificación Molecular/métodos , Alicyclobacillus/clasificación , Alicyclobacillus/aislamiento & purificación , ADN Bacteriano/genética , ADN Ribosómico/genética , Variación Genética/genética , Genotipo , Guayacol/metabolismo , Datos de Secuencia Molecular , Fenotipo , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética
12.
World J Microbiol Biotechnol ; 31(2): 359-69, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25566818

RESUMEN

The process of cocoa fermentation is a very important step for the generation or aromatic compounds, which are attributable to the metabolism of the microorganisms involved. There are some reports about this process and the identification of microorganisms; however, there are no reports identifying the yeasts involved in a Mexican cocoa fermentation process using molecular biology techniques, including restricted fragment length polymorphism (RFLP) and denaturing gradient gel electrophoresis (DGGE). The aim of this study was to identify the main yeast species associated with Mexican cocoa fermentations employing culture-dependent and -independent techniques achieving two samplings with a 1 year time difference at the same site. Isolation of the microorganisms was performed in situ. Molecular identification of yeast isolates was achieved by RFLP analysis and rDNA sequencing. Total DNA from the microorganisms on the cocoa beans was utilized for the DGGE analysis. Bands from the DGGE gels were excised and sequenced. Nineteen isolated yeasts were identified (al specie level), three of which had never before been associated with cocoa fermentations worldwide. The detected predominant yeast varied from one technique to another. Hanseniaspora sp. resulted dominant in DGGE however Saccharomyces cerevisiae was the principal isolated species. In conclusion, the culture-dependent and -independent techniques complement each other showing differences in the main yeasts involved in spontaneous cocoa fermentation, probably due to the physiological states of the viable but non culturable yeasts. Furthermore important differences between the species detected in the two samplings were detected.


Asunto(s)
Cacao/microbiología , Técnicas de Tipificación Micológica/métodos , Levaduras/clasificación , Levaduras/aislamiento & purificación , ADN de Hongos/análisis , ADN Ribosómico/análisis , Fermentación , Microbiología de Alimentos , México , Especificidad de la Especie , Levaduras/genética
13.
J Oral Pathol Med ; 43(7): 507-13, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25184162

RESUMEN

OBJECTIVES: The aim of this study was to study the loss of asymmetrical proliferation in oral tumorigenesis. MATERIALS AND METHODS: Samples: 92 oral squamous cell carcinomas (OSCC) with associated non-tumor epithelia (NTE). NTE and tumor were classified as distant from or close to the invasion point. Immunohistochemistry was performed using Mib-1 antibody. Ki-67 was assessed in basal, parabasal layer, medium and upper third, counting total and positive cells. Proliferative patterns were classified according to the ki-67 expression: 1 = expression in parabasal layers of well-differentiated tumor nest (WDTN); 2 = expression in parabasal and basal layers of WDTN; 3 = ki-67 expression in <20% cells in tumor tissue without WDTN; 4 = ki-67 expression in ≥20% of cells in tumor tissue without WDTN; and 5 = ki-67 expression exclusively found in basal layers of WDTN. RESULTS: Ki-67 expression was highest in parabasal layers of both close and distant NTE (39.7 ± 27.6 and 30.1 ± 20) and was also elevated in the close (43.4 ± 21.3) and distant (48.8 ± 21.9) tumor tissue samples. Close tumors largely corresponded to proliferation patterns 2 and 4, while distant tumors generally followed pattern 4. Of the 92 close NTE samples, 23 showed reduced basal proliferation with increased parabasal proliferation. Tumors derived from these epithelia followed patterns 2 (52%, 12/23 cases) or 4 (30.4%, 7/23 cases). Parabasal proliferation in distant NTE was significantly increased in patients with multiple vs. single tumors (36.7% vs. 25.4%; P = 0.032). CONCLUSION: The change from asymmetrical to symmetrical division appears to be an oncogenic mechanism in oral carcinogenesis.


Asunto(s)
Carcinoma de Células Escamosas/patología , Transformación Celular Neoplásica/patología , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Anciano , Anciano de 80 o más Años , División Celular Asimétrica , Carcinogénesis , Proliferación Celular , Epitelio/patología , Femenino , Humanos , Antígeno Ki-67/análisis , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Células Madre Neoplásicas/patología , Lesiones Precancerosas/patología , Neoplasias de la Lengua/patología
14.
Oral Oncol ; 50(9): 818-24, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24998198

RESUMEN

ß-Catenin is a multiple function protein. These functions derive from its interactions with other cell proteins, both on the cell membrane, in the cytoplasm and in the nucleus. ß-Catenin forms a complex with the adhesion molecule E-cadherin, promoting cell-cell adhesion and thereby preventing the cell dissociation that is required for cancer invasion and progression mechanisms. There is also a dynamic pool of cytoplasmic ß-catenin that serves as connection between the extracellular microenvironment and the nucleus. Cytoplasmic ß-catenin acts as a transcription factor for the nucleus in the canonical Wnt pathway, activating the transcription of various genes. Structural or functional alterations of ß-catenin can promote cancer progression. This review addresses the current knowledge on the implications of ß-catenin in the development of oral cancer.


Asunto(s)
Neoplasias de la Boca/fisiopatología , beta Catenina/fisiología , Progresión de la Enfermedad , Humanos
15.
Oral Oncol ; 49(8): 738-46, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23642758

RESUMEN

It has been proposed that the development of tumors is based exclusively on the activity of cancer stem cells (CSCs) leading to a new model of carcinogenesis, the CSC hypothesis, in opposition to the conventional model of clonal evolution. The new model may help to explain the high mortality of oral cancer, unchanged over the past decades, the low response to treatment and the tendency of oral squamous cell carcinoma (OSCC) patients to develop multiple tumors. However, a more profound understanding of the molecular pathways involved in maintaining the stem cell (SC) state and of their alterations is required to elucidate the mechanisms underlying the development of tumors and metastatic spread, but research into SC biopathology is hampered by the lack of specific markers for identifying SCs and CSCs in tissues and for establishing topographic relationships with their lineage. We review current knowledge on stem cells in relation to oral cancer, including their possible origins, focusing on the CSC hypothesis of oral tumorigenesis and attempts being made to identify oral stem cells.


Asunto(s)
Neoplasias de la Boca/patología , Células Madre Neoplásicas/patología , Carcinogénesis , Humanos , Procesos Estocásticos
16.
Oral Dis ; 19(4): 360-5, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22970847

RESUMEN

OBJECTIVE: To compare the proliferative activity in ameloblastoma and malignant odontogenic tumors, as assessed by Ki-67 immunostaining and determine whether expression of substance P (SP) and NK-1 receptor (NK-1R) is related to cell proliferation in these tumors. MATERIALS AND METHODS: Immunohistochemistry was used to evaluate protein expression in 44 benign and malignant odontogenic tumors from 39 patients. Immunohistochemistry was performed with anti-SP, anti-NK-1R, and anti-Ki-67 monoclonal antibodies, and the clinical and pathological data of the patients with odontogenic tumor were evaluated. RESULTS: Expression of Ki-67 in malignant odontogenic tumors was significantly higher than in ameloblastomas (P < 0.001), and the expression level was associated with higher expression of NK-1R. Among the ameloblastomas, there was significantly higher expression of Ki-67 in peripheral ameloblastic-like cells (3.3 ± 4.1) than in stellate reticulum-like cells (2.6 ± 3.7) (P = 0.04). In the majority of tissue locations of the malignant tumors, expression of SP and NK-1R was positively correlated with higher expression of Ki-67. CONCLUSION: These findings show that the expression level of Ki-67 in ameloblastomas was positively correlated with the rate of growth of odontogenic tumors. Overexpression of NK-1R complex in malignant odontogenic tumors could be part of the trigger stimulus that results in higher proliferative activity of the tumor.


Asunto(s)
Ameloblastoma/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Mandibulares/metabolismo , Neoplasias Maxilares/metabolismo , Tumores Odontogénicos/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ameloblastoma/patología , Proliferación Celular , Transformación Celular Neoplásica/metabolismo , Niño , Femenino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Neoplasias Mandibulares/patología , Neoplasias Maxilares/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Tumores Odontogénicos/patología , Receptores de Neuroquinina-1/metabolismo , Sustancia P/metabolismo , Adulto Joven
17.
Br J Oral Maxillofac Surg ; 51(2): 157-63, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22658605

RESUMEN

Our aim was to find out whether the loss of E-cadherin is a risk factor for the development of multiple tumours in the oral cavity and whether it could serve as a diagnostic marker for oral premalignant fields. We studied 77 oral squamous cell carcinomas (SCC) with associated non-tumour epithelia from 61 patients. Immunohistochemical studies (antibody NHC-38) were used to investigate E-cadherin expression, which was completely lost in basal (48% of cases) and parabasal (43%) layers of non-tumour epithelia close to the tumour and in basal (47%) and parabasal (38%) layers of non-tumour epithelia distant from the tumour. In multiple tumours E-cadherin expression was significantly lower than in single tumours in the basal, parabasal layers, and the middle third of close (p=0.002, <0.001, <0.001) and distant (p=0.041, p<0.001, p=0.005) non-tumour epithelia, respectively. Downregulation of E-cadherin may be valuable as a risk marker for the development of multiple tumours in the oral cavity and for the diagnosis of premalignant fields.


Asunto(s)
Biomarcadores de Tumor/análisis , Cadherinas/análisis , Carcinoma de Células Escamosas/patología , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Neoplasias Primarias Múltiples/patología , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Carcinoma de Células Escamosas/secundario , Estudios de Casos y Controles , Regulación hacia Abajo , Epitelio/patología , Femenino , Encía/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/patología , Mucocele/patología , Invasividad Neoplásica , Estadificación de Neoplasias , Lesiones Precancerosas/patología , Curva ROC , Estudios Retrospectivos , Factores de Riesgo
18.
Oral Dis ; 18(1): 40-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21851509

RESUMEN

The development of multiple oral tumours, seen in up to 30% of patients with a primary oral squamous cell carcinoma, is sometimes attributable to the presence of genetically altered premalignant fields and has important prognostic implications. Molecular techniques available for the definitive diagnosis of such a field (loss of heterozygosity analysis of 3p, 9p and 17p and study of TP53 tumour suppressor gene mutation) are expensive, complex and not universally available, hampering their routine application. Nevertheless, molecular diagnosis is essential for modern assessment of the risk of multiple tumours and for decisions on the appropriate preventive and therapeutic approaches. This article reviews current knowledge on molecular findings in premalignant fields in the oral cavity and oropharynx and provides an update on criteria for their identification, discussing the clinical and therapeutic implications.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias de la Boca/genética , Recurrencia Local de Neoplasia/genética , Neoplasias Primarias Múltiples/genética , Neoplasias Primarias Secundarias/genética , Lesiones Precancerosas/diagnóstico , Lesiones Precancerosas/genética , Biomarcadores de Tumor/análisis , Proteínas de Ciclo Celular/análisis , Quimioprevención , Aberraciones Cromosómicas , Análisis Citogenético , Epitelio/patología , Humanos , Antígeno Ki-67/análisis , Pérdida de Heterocigocidad , Repeticiones de Microsatélite , Técnicas de Diagnóstico Molecular , Reacción en Cadena de la Polimerasa Multiplex , Mutación , Pronóstico , Proteínas Supresoras de Tumor/genética
19.
Food Chem ; 132(1): 277-88, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26434291

RESUMEN

The effects of fermentation time and drying temperature on the profile of volatile compounds were evaluated after 2, 4, 6, and 8 fermentation days followed by drying at 60, 70 and 80°C. These treatments were compared with dry cocoa controls produced in a Samoa drier and by a sun-drying process. A total of 58 volatile compounds were identified by SPME-HS/GC-MS and classified as: esters (20), alcohols (12), acids (11), aldehydes and ketones (8), pyrazines (4) and other compounds (3). Six days of fermentation were enough to produce volatile compounds with flavour notes desirable in cocoa beans, as well as to avoid the production of compounds with off-flavour notes. Drying at 70 and 80°C after six fermentation days presented a volatile profile similar to the one obtained by sun drying. However, drying at 70°C represents a lower cost. Given the above results, in the present study the optimal conditions for fermentation and drying of cocoa beans were 6days of fermentation, followed by drying at 70°C.


Asunto(s)
Cacao/química , Fermentación/fisiología , Compuestos Orgánicos Volátiles/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Temperatura
20.
J Oral Pathol Med ; 40(9): 721-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21521368

RESUMEN

BACKGROUND: Sjögren's syndrome (SS) occurs associated with parotid neoplasm, non-Hodgkin's B-cell lymphoma, which could impair the condition or be life-threatening for patients. The aim of this work was to analyze cell proliferation and apoptosis modifications in acinar, ductal and inflammatory infiltrate in salivary glands (SG) in patients with Sjögren Syndrome, keratoconjunctivitis, or stomatitis sicca or in healthy subjects, to establish parameters that indicate the likelihood of malignancy of the disease in populations at risk. METHODS: A study was performed with n = 58 histological samples of lower lip SG from patients diagnosed with SS, keratoconjunctivitis, or stomatitis sicca (SICCA) and from healthy subjects (C). Ki67 and caspase-3 immunolabeling were performed. RESULTS: The most important result was significant differences between the three study groups in Ki67 and caspase-3 markers (P < 0.0001) in infiltrated lymphocytes. CONCLUSION: The results of this work are indicative of a high degree of proliferation (85%) in infiltrated lymphocytes (IL) associated with SS which, according the literature, could be considered a risk. Furthermore, the markers used in this work are widely known and represent a lower cost than others and can be used to determine risk groups within the population of SS patients, enabling their follow-up.


Asunto(s)
Apoptosis/fisiología , Glándulas Salivales/patología , Síndrome de Sjögren/patología , Caspasa 3/análisis , Proliferación Celular , Transformación Celular Neoplásica/patología , Humanos , Queratoconjuntivitis/patología , Antígeno Ki-67/análisis , Labio/patología , Linfocitos/patología , Factores de Riesgo , Conductos Salivales/patología , Glándulas Salivales Menores/patología , Sialadenitis/patología , Xerostomía/patología
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