In Silico Analysis of Genes Associated with the Pathogenesis of Odontogenic Keratocyst.

Odontogenic keratocyst (OK) is a benign intraosseous cystic lesion characterized by a parakeratinized stratified squamous epithelial lining with palisade basal cells. It represents 10-12% of odontogenic cysts. The changes in its classification as a tumor or cyst have increased interest in its pathogenesis. OBJECTIVE: Identify key genes in the pathogenesis of sporadic OK through in silico analysis. MATERIALS AND METHODS: The GSE38494 technical sheet on OK was analyzed using GEOR2. Their functional and canonical signaling pathways were enriched in the NIH-DAVID bioinformatic platform. The protein-protein interaction network was constructed by STRING and analyzed with Cytoscape-MCODE software v 3.8.2 (score > 4). Post-enrichment analysis was performed by Cytoscape-ClueGO. RESULTS: A total of 768 differentially expressed genes (DEG) with a fold change (FC) greater than 2 and 469 DEG with an FC less than 2 were identified. In the post-enrichment analysis of upregulated genes, significance was observed in criteria related to the organization of the extracellular matrix, collagen fibers, and endodermal differentiation, while the downregulated genes were related to defensive response mechanisms against viruses and interferon-gamma activation. CONCLUSIONS: Our in silico analysis showed a significant relationship with mechanisms of extracellular matrix organization, interferon-gamma activation, and response to viral infections, which must be validated through molecular assays.

LRP5, SLC6A3, and SOX10 Expression in Conventional Ameloblastoma.

Cell proliferation and invasion are characteristic of many tumors, including ameloblastoma, and are important features to target in possible future therapeutic applications. OBJECTIVE: The objective of this study was the identification of key genes and inhibitory drugs related to the cell proliferation and invasion of ameloblastoma using bioinformatic analysis. METHODS: The H10KA_07_38 gene profile database was analyzed by Rstudio and ShinyGO Gene Ontology enrichment. String, Cytoscape-MCODE, and Kaplan-Meier plots were generated, which were subsequently validated by RT-qPCR relative expression and immunoexpression analyses. To propose specific inhibitory drugs, a bioinformatic search using Drug Gene Budger and DrugBank was performed. RESULTS: A total of 204 significantly upregulated genes were identified. Gene ontology enrichment analysis identified four pathways related to cell proliferation and cell invasion. A total of 37 genes were involved in these pathways, and 11 genes showed an MCODE score of ≥0.4; however, only SLC6A3, SOX10, and LRP5 were negatively associated with overall survival (HR = 1.49 (p = 0.0072), HR = 1.55 (p = 0.0018), and HR = 1.38 (p = 0.025), respectively). The RT-qPCR results confirmed the significant differences in expression, with overexpression of >2 for SLC6A3 and SOX10. The immunoexpression analysis indicated positive LRP5 and SLC6A3 expression. The inhibitory drugs bioinformatically obtained for the above three genes were parthenolide and vorinostat. CONCLUSIONS: We identify LRP5, SLC6A3, and SOX10 as potentially important genes related to cell proliferation and invasion in the pathogenesis of ameloblastomas, along with both parthenolide and vorinostat as inhibitory drugs that could be further investigated for the development of novel therapeutic approaches against ameloblastoma.

Análisis inmunohistoquímico de MMP-1, MMP-2 y MMP-9 en ameloblastoma convencional / Immunohistochemical analysis of MMP-1, MMP-2, MMP-9 in conventional ameloblastoma

Introducción: las metaloproteinasas son enzimas que participan en la remodelación tisular y su función se relaciona con procesos fisiológicos y patológicos, como la invasión y la metástasis. El ameloblastoma convencional (AMC) es una neoplasia epitelial benigna odontogénica intraósea caracterizada por una progresión lenta y localmente invasiva, cuyo crecimiento se ha vinculado con el recambio ósea y la remodelación de la matriz extracelular. El objetivo del presente trabajo fue determinar la presencia inmunohistoquímica de MMP-1, MMP-2 y MMP-9 en el AMC. Material y métodos: se realizó un estudio piloto observacional analítico utilizando cinco muestras de AMC. Los especímenes fueron recolectados aleatoriamente del archivo del Departamento de Patología Oral y Maxilofacial, de la Escuela Nacional de Estudios Superiores (ENES) Unidad León, UNAM. Como grupo control se emplearon dos especímenes de folículo dental, obtenido de pacientes con indicación de su extracción por motivos ortodóncicos. Se realizó la técnica de inmunohistoquímica por peroxidasa, recolectando el nivel y proporción de inmunoexpresión de manera semicuantitativa. Resultados: cuatro pacientes fueron de género masculino y uno femenino, la edad promedio fue de 40.6 ± 14.9 años. Todas las muestras fueron obtenidas de la región mandibular posterior. Se observaron dos especímenes con patrón folicular y tres con plexiforme. Las MMP-2 y MMP-9 se detectaron sólo en uno de los cinco especímenes y únicamente en el parénquima de la lesión, con una proporción de 100%. Conclusión: según nuestro análisis inmunohistoquímico, las MMP-2 y MMP-9 son las metaloproteinasas que presentaron expresión positiva dentro de la patogénesis del AMC comparado a la MMP-1; no obstante, es necesario realizar este tipo de estudios en una población mayor (AU)

Introduction: metalloproteinases are enzymes involved in tissue remodeling and their function is related to physiological and pathological processes, such as invasion and metastasis. These enzymes are capable of degrading components of the extracellular matrix, which may promote tumor progression. Conventional ameloblastoma (CA) is described as a benign intraosseous epithelial odontogenic neoplasm characterized by a slow and locally invasive progression, whose growth has been linked to bone turnover and extracellular matrix remodeling. The aim of the present work was to determine the immunohistochemical presence of MMP-1, MMP-2 and MMP-9 in CA. Material and methods: an analytical observational pilot study was performed using 5 CA, randomly collected from the archive of the Department of Oral and Maxillofacial Pathology, Escuela Nacional de Estudios Superiores (ENES) Unidad León, UNAM. The control group used were two dental follicle samples, obtained from patients with extraction indication for orthodontic treatment. The peroxidase immunohistochemistry assay was performed, collecting semiquantitatively level and proportion of immunoexpression. Results: four patients were male and one female, the average age was 40.6 ± 14.9 years. All specimens were obtained from the posterior mandibular region. Two specimens were observed with follicular pattern and three with plexiform pattern. MMP-2 and MMP-9 were detected only in one of the five specimens, with presence in the parenchyma of the lesion, with a proportion of 100% of the cell analyzed. Conclusion: according to our immunohistochemical analysis, MMP-2 and MMP-9 are the metalloproteinases that presented positive expression within the pathogenesis of CA compared to MMP-1; however, it is necessary to perform this type of studies in a larger population (AU)

Conventional Ameloblastoma. A Case Report with Microarray and Bioinformatic Analysis.

Ameloblastoma is a rare benign epithelial odontogenic neoplasm, but with great clinical implications, as despite its benignity and slow growth, most cases are locally aggressive with a significant recurrence rate. Histological, cellular, or molecular analyses of its pathogenesis have confirmed the complexity of this neoplasm. We present the case of a 20-year-old patient with a suggestive clinical and radiographic diagnosis of ameloblastoma. An incisional biopsy was obtained confirming the diagnosis of conventional ameloblastoma. Left hemimandibulectomy and plate reconstruction were performed. Histopathological analysis of the surgical specimen confirmed the conventional ameloblastoma with a plexiform pattern and significant areas of cystic degeneration and amyloid-like-like deposits. Additionally, a microarray was carried out with bioinformatic analysis for the enrichment, protein interaction, and determination of eight hub genes (CRP, BCHE, APP, AKT1, AGT, ACTC1, ADAM10, and APOA2) related to their pathogenesis.

Bioinformatic Analysis for Mucoepidermoid and Adenoid Cystic Carcinoma of Therapeutic Targets.

Salivary gland neoplasms are a heterogeneous neoplasm group, including mucoepidermoid carcinoma (MECa), adenoid cystic carcinoma (AdCC), and many others. OBJECTIVE: We aimed to identify new critical genes of MECa and AdCC using bioinformatics analysis. METHODS: Gene expression profile of GSE153283 was analyzed by the GEO2R online tool to use the DAVID software for their subsequent enrichment. Protein-protein interactions (PPI) were visualized using String. Cytoscape with MCODE plugin followed by Kaplan-Meier online for overall survival analysis were performed. RESULTS: 97 upregulated genes were identified for MECa and 86 for AdCC. PPI analysis revealed 22 genes for MECa and 63 for AdCC that were validated by Kaplan-Meier that showed FN1 and SPP1 for MECa, and EGF and ERBB2 for AdCC as more significant candidate genes for each neoplasm. CONCLUSION: With bioinformatics methods, we identify upregulated genes in MECa and AdCC. The resulting candidate genes as possible therapeutic targets were FN1, SPP1, EGF, and ERBB2, and all those genes had been tested as a target in other neoplasm kinds but not salivary gland neoplasm. The bioinformatic evidence is a solid strategy to select them for more extensive research with clinical impact.

Microarray and bioinformatic analysis of conventional ameloblastoma: an observational analysis

Abstract Ameloblastoma is a highly aggressive odontogenic tumor, and its pathogenesis is associated with many participating genes. Objective We aimed to identify and validate new critical genes of conventional ameloblastoma using microarray and bioinformatics analysis. Methodology Gene expression microarray and bioinformatic analysis were performed using CHIP H10KA and DAVID software for enrichment. Protein-protein interactions (PPI) were visualized using STRING-Cytoscape with MCODE plugin, followed by Kaplan-Meier and GEPIA analyses that were used for the candidate's postulation. RT-qPCR and IHC assays were performed to validate the bioinformatic approach. Results 376 upregulated genes were identified. PPI analysis revealed 14 genes that were validated by Kaplan-Meier and GEPIA resulting in PDGFA and IL2RA as candidate genes. The RT-qPCR analysis confirmed their intense expression. Immunohistochemistry analysis showed that PDGFA expression is parenchyma located. Conclusion With bioinformatics methods, we can identify upregulated genes in conventional ameloblastoma, and with RT-qPCR and immunoexpression analysis validate that PDGFA could be a more specific and localized therapeutic target.

Inmunoexpresión de p53 y su relación con el grado de severidad en displasia epitelial oral / Immunoexpression of p53 and its relationship with the degree of severity in oral epithelial dysplasia

Introducción: La displasia epitelial oral (DEO) es la presencia de alteraciones celulares y tisulares, lo que puede significar una etapa anterior al desarrollo del cáncer. Múltiples marcadores han sido considerados para estimar su potencial neoplásico y evolución a carcinoma, incluyendo a la molécula p53, se considera como participe de diversos fenómenos de la homeostasis celular. Objetivo: Determinar la relación entre la inmunoexpresión de p53 DO-7 y PAb 240 con el grado de severidad de la displasia epitelial oral. Material y métodos: Se analizaron nueve muestras de DEO (tres para cada grado de severidad). La inmunoexpresión de p53 tipo silvestre (DO-7) y forma mutada (PAb 240), fue determinada a través de ensayo de inmunohistoquímica por peroxidasa. Se obtuvieron la media y desviación estándar y se realizó la prueba χ2 (p < 0.05). Resultados: La edad media fue de 65.7 ± 11.4 años, la zona anatómica con mayor presencia de DEO es el borde lateral de la lengua. Ocho de nueve muestras fueron positivas para DO-7 y solo dos para PAb 240. Conclusiones: Nuestros resultados indican que, aunque la expresión de p53 DO-7 podría estar relacionada parcialmente con la patogénesis de la displasia epitelial, no todas las displasias presentaron la forma mutada de p53 (PAb 240). Lo cual coincide con el comportamiento biológico incierto de las displasias al poder permanecer sin cambios, involucionar o transformarse

Introduction: Oral epithelial dysplasia (OED) is the presence of cellular and tissue alterations, which may mean a stage prior to the development of cancer. Multiple markers have been considered to estimate its pathogenic potential and evolution to neoplasms, including the p53 molecule, considered as participating in various phenomena of cellular homeostasis. Objective: To determine the relationship between the immunoexpression of p53 DO-7 and PAb 240 with the degree of severity of oral epithelial dysplasia. Material and methods: Nine OED samples were analyzed (three for each degree of severity). The immunoexpression of wild-type p53 (DO-7) and mutated form (PAb 240) was determined through a peroxidase immunohistochemical assay. The mean and standard deviation were obtained, and χ2 test (p < 0.05) were performed. Results: The mean age was 65.7 ± 11.4 years, with a greater presence of OED in the anatomical area of the lateral side of the tongue. Eight out of nine samples were positive for DO-7 and only two for PAb 240. Conclusions: Our results indicate that, although the expression of p53 DO-7 could be partially related to the pathogenesis of epithelial dysplasia, not all dysplasias presented the mutated form of p53 (PAb 240), which coincides that not all dysplasias have a potential for malignant transformation and that could be related to other oncogenic mechanisms (AU)

Epstein-Barr virus-positive ulcer in the oral cavity.

Epstein-Barr virus-positive ulcer (EBV + U) is a recently reported B cell lymphoproliferative disorder in the oral cavity, oropharynx, gastrointestinal tract and skin, principally in immunosuppressed patients. A 53-year-old female patient with rheumatoid arthritis treated with methotrexate, presenting ulcers of unknown duration on the dorsum and the lateral left border of the tongue. Excisional biopsy, histopathological analysis and histochemical stains for syphilis (Warthin-Starry), mycotic diseases (Grocott silver methenamine), tuberculosis (Ziehl-Neelsen), immunohistochemistry tests for herpesvirus type 8 (CMV), EBV (LMP-1) and DNA extraction for polymerase chain reaction (PCR) assay to CMV, EBV and herpes simplex virus-1 were performed. Posterior to PCR assay, the final diagnosis was EBV + U in the oral cavity. Acyclovir® was prescribed, showing clinical improvement. A case of EBV + U with clinical characteristics similar to other lesions or conditions has been reported. Special assays are necessary for an accurate diagnosis and treatment.

Análisis de microdensidad vascular y factores de crecimiento en carcinoma oral de células escamosas / Analysis of vascular microdensity and growth factors in oral squamous cell carcinoma

Introducción: El carcinoma oral de células escamosas (COCE) es una neoplasia epitelial maligna que se presenta frecuentemente entre la quinta y sexta década de la vida. Su compleja patogénesis incluye el proceso de angiogénesis y la regulación del microambiente tumoral como mecanismos de progresión tumoral. Objetivo: Determinar la relación entre las variables clínicas e histológicas del COCE con la inmunoexpresión de VEGF, FGF-1, FGFR-1, TGFB-1, TGFBR-II y CD105. Material y métodos: Nueve casos de COCE; tres bien (BD), tres moderado (MD) y tres pobremente diferenciados (PD) obtenidos del Departamento de Patología y Medicina Bucal, División de Estudios de Postgrado e Investigación. Se aplicó la técnica de inmunohistoquímica por peroxidasa para identificar la expresión de VEGF, FGF-1, FGFR- 1, TGFB-1, TGFBR-II y CD105. El análisis de inmunoexpresión se realizó con el programa ImageJ. Se aplicó la prueba de Kruskal-Wallis y correlación de Spearman (p < 0.05). Resultados: La inmunoexpresión de VEGF fue mayor en los COCE PD, FGFR-1 fue positivo en los BD, mientras que FGF, TGFB-1 y TGFBR-II fueron negativos. El análisis de microdensidad vascular (MVD) indicó mayor número de vasos CD105 positivos en los carcinomas BD, seguidos de los PD y MD. Conclusión: Considerando los resultados obtenidos podemos concluir que la angiogénesis es un fenómeno constante independiente del grado de diferenciación que durante el proceso de transformación de una neoplasia requerirá la formación de vasos sanguíneos y que este proceso puede ser modulado por factores de crecimiento tales como los analizados en este trabajo (AU)

Introduction: Oral squamous cell carcinoma (OSCC) is a malignant epithelial neoplasm that frequently occurs between the fifth and sixth decade of life. Its complex pathogenesis includes the angiogenesis process and the regulation of the tumor microenvironment as mechanisms of tumor progression. Objective: To determine the relationship between the clinical and histological variables of OSCC with the immunoexpression of VEGF, FGF-1, FGFR-1, TGFB- 1, TGFBR-II and CD105. Material and methods: Nine cases of OSCC; three well (WD), three moderate (MD) and three poorly differentiated (PD) obtained from the Oral Medicine and Pathology Department, Division of Graduate Studies and Research. The peroxidase immunohistochemistry technique was performed to identify the expression of VEGF, FGF-1, FGFR-1, TGFB-1, TGFBR-II and CD105. The immunoexpression analysis was performed with the ImageJ software. The Kruskal-Wallis and Spearman correlation test were performed (p < 0.05). Results: VEGF immunoexpression was higher in PD OSCC, while FGFR-1 was predominantly positive in WD; FGF, TGFB-1 and TGFBR-II were negative. Vascular microdensity analysis (MVD) indicated a greater number of CD105 positive vessels in WD carcinomas, followed by PD and MD. Conclusion: Considering the results obtained, we can conclude that angiogenesis is a constant phenomenon independent of the degree of differentiation; that during the transformation process of a neoplasm it will require the formation of blood vessels and that this process can be modulated by growth factors such as those analyzed in this work (AU)

Evaluación de la citotoxicidad de Biodentine, IRM y MTA en cultivos de fibroblastos del ligamento periodontal humano / An evaluation of the cytotoxicity of Biodentine, IRM and MTA in cultures of human periodontal ligament fibroblasts

Introducción: Los materiales para la obturación retrógrada son diversos. Actualmente, IRM y MTA son las alternativas clínicas más utilizadas, no obstante, es relativamente reciente la introducción de materiales a base de silicatos tricálcicos tal como Biodentine. Objetivo: Determinar la citotoxicidad de fibroblastos del ligamento periodontal humano expuestos a medios de cultivo condicionados con Biodentine, IRM y MTA. Material y métodos: 1 × 103 fibroblastos del ligamento periodontal humano fueron expuestos a medios DMEM/F12 condicionados con MTA, IRM y Biodentine en tres protocolos diferentes. Se realizó un ensayo de MTT para determinar la viabilidad celular a las cero, 24, 48, 72 horas, siete y 14 días. Se realizó una prueba ANOVA (p < 0.05). Resultados: En los tres protocolos con los diferentes medios de cultivo condicionados, la viabilidad de las células fue predominantemente proliferativa; sin embargo, las células expuestas a Biodentine mostraron una tendencia mayor que la MTA o la IRM. Conclusión: Las células expuestas a la Biodentine mostraron un comportamiento proliferativo a los 14 días de análisis. Se debe realizar más investigación a nivel in vivo y clínico para obtener más información sobre la conducta de estos materiales empleados para la obturación retrógrada (AU)

Introduction: The materials for retrograde filling are diverse. Currently, IRM and MTA are the most commonly used clinical alternatives, however, the introduction of materials based on tricalcium silicates such as Biodentine is relatively recent. Objective: To determine the cytotoxicity of human periodontal ligament fibroblasts exposed to culture media conditioned with Biodentine, IRM and MTA. Material and methods: 1 × 103 fibroblasts of the human periodontal ligament were exposed to DMEM/F12 media conditioned with MTA, IRM and Biodentine in 3 different protocols. An MTT assay was performed to determine cell viability at 0, 24, 48, 72 hours, seven and 14 days. An ANOVA test was performed (p < 0.05). Results: In the three protocols with the different conditioned culture media, the viability of the cells was predominantly proliferative, however, the cells exposed to Biodentine showed a higher tendency than the MTA or the IRM. Conclusion: The cells exposed to the Biodentine showed a proliferative behavior at 14 days of analysis. More research should be done at in vivo and clinical level to obtain more information about the behavior of these materials used for retrograde filling (AU)

Immunohistochemical patterns in different stromal variants of pleomorphic adenomas: literature review.

Pleomorphic adenoma is the most frequent type of benign salivary neoplasm located in the mouth and is characterized by its significant histopathological diversity. The histogenesis of the pleomorphic adenoma is uncertain; so far several studies suggest that myoepithelial cells are responsible for the variable histomorphology of this type of neoplasm. At times, stroma is the predominant element. The purpose of the present review is to analyze the results reported in the scientific literature concerning immunomarkers expressed in the different stromal elements of pleomorphic adenoma.

Prevalence trends of oral squamous cell carcinoma. Mexico City’s General Hospital experience

Objective: Recent reports suggest an increase in oral squamous cell carcinoma (OSCC) frequency. To improve programs in public health, it is necessary to understand the epidemiological conditions. The aim of this study was to analyze the trend in gender, age, anatomic zone and OSCC stage from Mexico City’s General Hospital patients from 1990 to 2008.Study design: A retrospective review of all OSCC cases diagnosed by the Pathology Department of the Mexico City General Hospital was performed. Demographic data, in addition to anatomic zone and histological degree of differentiation were obtained. Central tendency, dispersion and prevalence rate per 100,000 individuals were determined. Results: A total of 531 patients were diagnosed with OSCC; 58.4% were men, giving a male: female ratio of 1.4:1, and the mean age was 62.5 ± 14.9 years. The predominant anatomic zone was the tongue (44.7%), followed by the lips (21.2%) and gums (20.5%). The most frequent histological degree was moderately differentiated in 325 cases (61.2%). The rates of OSCC prevalence showed similar (..) (AU)

erbB expression changes in ethanol and 7, 12- dimethylbenz (a) anthracene-induced oral carcinogenesis

Objetive: The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster’s buccal pouch chemical carcinogenesis model. Study design: Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experimental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumors per cheek, volume, histological condition, erbB expression were determined and results were analyzed by the Mann–Whitney U and Dunn’s test. Results: Control groups and those exposed to alcohol (A, B and C respectively) only presented clinical and histological normal mucosa; while those exposed to DMBA or DMBA plus alcohol (D and E groups) developed dysplasia and invasive carcinomas. erbB2, erbB3, and erbB4 increased their expression in alcohol-exposed mucosa, dysplasia, and invasive carcinomas. We observed a similar expression level for erbB2 in dysplasia and carcinomas; while, erbB3 and erbB4 were similar only in carcinomas. Conclusion: The DMBA and alcohol can be considered as carcinogen and promoter for oral carcinogenesis. TheerbB expression is different according to their histological condition, suggesting differential participation of theerbB family in oral carcinogenesis induced by alcohol and DMBA (AU)

Prevalence trends of oral squamous cell carcinoma. Mexico City's General Hospital experience.

OBJECTIVE: Recent reports suggest an increase in oral squamous cell carcinoma (OSCC) frequency. To improve programs in public health, it is necessary to understand the epidemiological conditions. The aim of this study was to analyze the trend in gender, age, anatomic zone and OSCC stage from Mexico City's General Hospital patients from 1990 to 2008. STUDY DESIGN: A retrospective review of all OSCC cases diagnosed by the Pathology Department of the Mexico City General Hospital was performed. Demographic data, in addition to anatomic zone and histological degree of differentiation were obtained. Central tendency, dispersion and prevalence rate per 100,000 individuals were determined. RESULTS: A total of 531 patients were diagnosed with OSCC; 58.4% were men, giving a male:female ratio of 1.4:1, and the mean age was 62.5 ± 14.9 years. The predominant anatomic zone was the tongue (44.7%), followed by the lips (21.2%) and gums (20.5%). The most frequent histological degree was moderately differentiated in 325 cases (61.2%). The rates of OSCC prevalence showed similar patterns in terms across time. A significant correlation (P = 0.007) between anatomic zone and age was observed. CONCLUSION: According to our results, the prevalence of OSCC does not show important variations; however, a relationship between age and anatomic zone was observed. These data could be used as parameters for the diagnosis of OSCC as well as for the development and dissemination of preventive programs for the early detection of oral cancer.

erbB expression changes in ethanol and 7,12- dimethylbenz (a)anthracene-induced oral carcinogenesis.

OBJECTIVE: [corrected] The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster's buccal pouch chemical carcinogenesis model. STUDY DESIGN: Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experimental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumors per cheek, volume, histological condition, erbB expression were determined and results were analyzed by the Mann-Whitney U and Dunn's test. RESULTS: Control groups and those exposed to alcohol (A, B and C respectively) only presented clinical and histological normal mucosa; while those exposed to DMBA or DMBA plus alcohol (D and E groups) developed dysplasia and invasive carcinomas. erbB2, erbB3, and erbB4 increased their expression in alcohol-exposed mucosa, dysplasia, and invasive carcinomas. We observed a similar expression level for erbB2 in dysplasia and carcinomas; while, erbB3 and erbB4 were similar only in carcinomas. CONCLUSION: The DMBA and alcohol can be considered as carcinogen and promoter for oral carcinogenesis. The erbB expression is different according to their histological condition, suggesting differential participation of the erbB family in oral carcinogenesis induced by alcohol and DMBA.

Fluoride consumption and its impact on oral health.

OBJECTIVE: The purpose of this study was to evaluate caries and dental fluorosis among Mexican preschoolers and school-aged children in a non-endemic zone for fluorosis and to measure its biological indicators. METHODS: DMFT, DMFS, dmft, dmfs, and CDI indexes were applied. Fluoride urinary excretion and fluoride concentrations in home water, table salt, bottled water, bottled drinks, and toothpaste were determined. RESULTS: Schoolchildren presented fluorosis (CDI = 0.96) and dental caries (DMFT = 2.64 and DMFS = 3.97). Preschoolers presented dmft = 4.85 and dmfs = 8.80. DMFT and DMFS were lower in children with mild to moderate dental fluorosis (DF). Variable fluoride concentrations were found in the analyzed products (home water = 0.18-0.44 ppm F, table salt = 0-485 ppm F, bottled water = 0.18-0.47 ppm F, juices = 0.08-1.42 ppm F, nectars = 0.07-1.30 ppm F, bottled drinks = 0.10-1.70 ppm F, toothpaste = 0-2,053 ppm F). Mean daily fluoride excretion was 422 ± 176 µg/24 h for schoolchildren and 367 ± 150 µg/24 h for preschoolers. CONCLUSIONS: Data from our study show that, despite values of excretion within an optimal fluoride intake range, the prevalence of caries was significant in both groups, and 60% of the 11- to 12-year-old children presented with dental fluorosis. In addition, variable fluoride concentrations in products frequently consumed by children were found.

Fluoride content in table salt distributed in Mexico City, Mexico.

OBJECTIVE: The aim of this study was to analyze table salt available in Mexico City's market to identify the fluoride concentrations and to compare these with the Mexican regulations. METHODS: We analyzed 44 different brands of table salt. All samples were purchased at random in different stores, supermarkets, and groceries from Mexico City's metropolitan area and analyzed in triplicate in three different laboratories (nine determinations per sample) with an Orion 720 A potentiometer and an Orion 9609 BN ion-specific electrode. RESULTS: Fluoride concentration in the samples varied from 0 ppm to 485 ppm. It was found that fluoride concentration varied widely among the analyzed brands. Also, we found that fluoride concentration in 92 percent of the analyzed samples did not match with that printed on the label. Only 6.8 percent of the analyzed samples contained fluoride concentrations that meet Mexican and WHO regulations. CONCLUSIONS: The broad variation in the analyzed samples suggests that Mexican Public Health authorities must implement more stringent regulation guidelines and procedures for controlling the distribution of salt and its fluoride concentration for human consumption.