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OBJECTIVES: DNA methylation is an important mechanism of gene control expression, and it has been poorly addressed in odontogenic tumours. On this basis, we aimed to assess the methylation pattern of 22 apoptosis-related genes in solid ameloblastomas. MATERIALS AND METHODS: Ameloblastoma fresh samples (n = 10) and dental follicles (n = 8) were included in the study. The percentage fraction of methylated and unmethylated DNA promoter of 22 apoptosis-related genes was determined using enzymatic restriction digestion and quantitative real-time PCR (qPCR) array. The relative expressions of the genes that showed the most discrepant methylation profile between tumours and controls were analysed by reverse-transcription quantitative PCR (RT-qPCR). RESULTS: Lower methylation percentages of TNFRSF25 (47.2%) and BCL2L11 (33.2%) were observed in ameloblastomas compared with dental follicles (79.3% and 59.5%, respectively). The RT-qPCR analysis showed increased expression of BCL2L11 in ameloblastomas compared with dental follicles, in agreement with the methylation analysis results, while there was no difference between the expression levels of TNFRSF25 between both groups. CONCLUSIONS: On the basis of our results, the transcription of the apoptosis-related gene BCL2L11 is possibly regulated by promoter DNA methylation in ameloblastoma. The biological significance of this finding in ameloblastoma pathobiology remains to be clarified.
Assuntos
Ameloblastoma/genética , Proteína 11 Semelhante a Bcl-2/genética , Metilação de DNA , Expressão Gênica , Neoplasias Maxilomandibulares/genética , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Adulto , Apoptose/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Adulto JovemRESUMO
Odontogenic tumors occur within the jaw bones and may be derived from odontogenic epithelium or ectomesenchyme or contain active components of both tissue types. We investigated the gene expression profile of enamel matrix proteins (EMPs), genes related to osteogenesis, and the mineralization process in odontogenic tumor cell populations focusing on an ameloblastoma (AB-1), a keratocystic odontogenic tumor (KCOT-1), and a calcifying epithelial odontogenic tumor (CEOT-1). All cell populations were shown to be epithelial in origin by CK14 expression. All tested EMPs were expressed by all odontogenic tumor cell types, with higher transcript levels seen in the AB-1 population especially for AMEL, AMBN, and ODAM. CEOT-1 cell populations showed a greater content of ALP-positive cells as well as higher ALP mRNA levels. Using qRT-PCR, we found a higher expression of 8 genes in the CEOT-1 compared to the AB-1 and KCOT-1. In this study we demonstrated the establishment of AB-1, KCOT-1 and CEOT-1 cell populations. The unique gene expression profiles of AB-1, KCOT-1, and CEOT-1 cells and their interactions with the surrounding microenvironment may support their unique tumor development, progression, and survival.
Assuntos
Esmalte Dentário/metabolismo , Esmalte Dentário/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Tumores Odontogênicos/genética , Osteogênese/genética , Linhagem Celular Tumoral , Proliferação de Células , Forma Celular , Proteínas do Esmalte Dentário/genética , Proteínas do Esmalte Dentário/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Tumores Odontogênicos/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
OBJECTIVE: WWOX gene is altered in a variety of neoplasms. Wwox is pro-apoptotic through interaction with p73 and may be involved in chromosomal stability by interaction with p73 and p53. The aims of this study were to characterize WWOX transcription, methylation status and immunoexpression in salivary neoplasms and to determine whether these were associated with p73, p53, cell proliferation and DNA ploidy. MATERIALS AND METHODS: Seven malignant and 21 benign fresh salivary neoplasms were included. WWOX expression was determined by RT-PCR and sequencing of transcripts, quantitative PCR and immunohistochemistry. Methylation-specific PCR was used to assess the methylation of its first exon. For p73, ΔNp73, p53 and ki67 immunohistochemistry and ploidy analysis, 29 malignant samples from archives were included. RESULTS: No consistent pattern of WWOX exon 1 methylation was found, but aberrant and novel transcripts were observed in 17/28 neoplasms; 55% of tumours showed reduced WWOX RNA. WWOX RNA levels were associated with p53 immunopositivity. Immunohistochemical Wwox expression did not correlate with methylation status, p53 or p73 expression or proliferation. p73, proliferation and DNA ploidy were associated with malignant phenotype. CONCLUSION: Aberrant WWOX transcription and decreased expression are frequent in salivary neoplasms and WWOX transcription is associated with p53 staining.
Assuntos
Apoptose/genética , Proteínas de Ligação a DNA/genética , DNA/genética , Proteínas Nucleares/genética , Oxirredutases/genética , Ploidias , Neoplasias das Glândulas Salivares/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Idoso , Aneuploidia , Proliferação de Células , Metilação de DNA/genética , Diploide , Éxons/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica/genética , Proteína Tumoral p73 , Oxidorredutase com Domínios WW , Adulto JovemRESUMO
In the present study we characterized titanium (Ti) surfaces submitted to different treatments and evaluated the response of osteoblasts derived from human alveolar bone to these surfaces. Five different surfaces were evaluated: ground (G), ground and chemical etched (G1-HF for 60 s), sand blasted (SB-Al(2)O(3) particles 65 mum), sand blasted and chemical etched (SLA1-HF for 60 s and SLA2-HF for 13 s). Surface morphology was evaluated under SEM and roughness parameters by contact scanning instrument. The presence of Al(2)O(3) was detected by EDS and the amount calculated by digital analyses. Osteoblasts were cultured on these surfaces and it was evaluated: cell adhesion, proliferation, and viability, alkaline phosphatase activity, total protein content, and matrix mineralization formation. Physical and chemical treatments produced very different surface morphologies. Al(2)O(3) residues were detected on SB and SLA2 surfaces. Only matrix mineralization formation was affected by different surface treatments, being increased on rough surface (SLA1) and reduced on surface with high amount of Al(2)O(3) residues (SB). On the basis of these findings, it is possible to conclude that high concentration of residual Al(2)O(3) negatively interfere with the process of matrix mineralization formation in contact with Ti implant surfaces.
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Óxido de Alumínio/química , Matriz Extracelular/metabolismo , Osteoblastos/metabolismo , Titânio/química , Fosfatase Alcalina/metabolismo , Adesão Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/metabolismo , Humanos , Microscopia Eletrônica de Varredura , Osteoblastos/fisiologia , Osteogênese , Propriedades de SuperfícieRESUMO
BACKGROUND: Recurrent aphthous stomatitis (RAS) is characterized by recurrent episodes of oral ulceration in an otherwise healthy individual. Some reports in the literature indicate that RAS may have immunological, psychological, genetic and microbiological bases. The purpose of the present study was to investigate the possible association between interleukin-1beta (IL-1beta) +3954 (C/T) genetic polymorphism and RAS in a sample of Brazilian patients. SUBJECTS AND METHODS: Sixty-two consecutive subjects affected by minor and major forms of RAS and 62 healthy volunteers were genotyped at IL-1beta (+3954). The chi-squared test was used for statistical analysis. RESULTS: A significant increase in the high production of IL-1beta genotype CT was observed in the group with RAS (P = 0.01). After stratifying RAS patients according to the mean number of lesions per episode, a significant difference was only observed between patients with >or=3 lesions in each episode and control. CONCLUSION: There is an increased frequency of polymorphism associated with high IL-1beta production in RAS patients.
Assuntos
Interleucina-1beta/genética , Estomatite Aftosa/genética , Adolescente , Adulto , Idoso , Brasil , Estudos de Casos e Controles , Criança , Citosina , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , TiminaRESUMO
Titanium samples of different roughness R(a) and morphology were prepared using a combination of mechanical (grinding with a SiC paper or blasting with aluminum oxide particles with 65 or 250 microm) and chemical (attack with a sulphuric acid based solution or a hydrofluoric acid based solution) treatments. The biological performance of the prepared surfaces was evaluated using human bone marrow osteoblastic cell cultures. Mechanically treated samples presented different R(a) values and surface morphology. The hydrofluoric acid solution was more effective than the sulphuric acid solution in smoothing titanium surface and also in eliminating aluminum contamination resulting from the blasting process. Bone marrow cells seeded on the different titanium samples showed a similar pattern of behavior during cell attachment and spreading. Cells proliferated very well on all the titanium surfaces and cell growth was observed during approximately two to three weeks. The samples treated with the hydrofluoric acid solution presented higher alkaline phosphatase activity. Only the blasted samples treated with the acid solutions allowed seeded bone marrow cells to form a mineralized extracellular matrix. The best biological performance was found in the blasted samples treated with the hydrofluoric acid solution, which could be related to the characteristic microtopography of these samples that presented a homogeneous and smooth roughness.
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No presente trabalho os autores analisam todos os casos de derrame pleural nao tuberculoso (47 casos) submetidos a tratamento clinico-cirurgico, em criancas admitidas na AMIP (Assistencia Medica Infantil da Paraiba) no ano de 1979. Os aspectos clinicos, os meios diagnosticos, a etiologia, bem como o tratamento instituido, suas complicacoes e o indice de mortalidade sao apresentados e discutidos
