RESUMO
The aim of the study was to characterize the molecular relationship between ameloblastoma and keratocystic odontogenic tumor (KCOT) by means of a genome-wide expression analysis. Total RNA from 27 fresh tumor samples of 15 solid/multicystic intraosseous ameloblastomas and 12 sporadic KCOTs was hybridized on Affymetrix whole genome arrays. Hierarchical clustering separated ameloblastomas and KCOTs into 2 distinct groups. The gene set enrichment analysis based on 303 dental genes showed a similar separation of ameloblastomas and KCOTs. Early dental epithelial markers PITX2, MSX2, DLX2, RUNX1, and ISL1 were differentially overexpressed in ameloblastoma, indicating its dental identity. Also, PTHLH, a hormone involved in tooth eruption and invasive growth, was one of the most differentially upregulated genes in ameloblastoma. The most differentially overexpressed genes in KCOT were squamous epithelial differentiation markers SPRR1A, KRTDAP, and KRT4, as well as DSG1, a component of desmosomal cell-cell junctions. Additonally, the epithelial stem cell marker SOX2 was significantly upregulated in KCOT when compared with ameloblastoma. Taken together, the gene expression profile of ameloblastoma reflects differentiation from dental lamina toward the cap/bell stage of tooth development, as indicated by dental epithelium-specific transcription factors. In contrast, gene expression of KCOT indicates differentiation toward keratinocytes.
Assuntos
Ameloblastoma/genética , Tumores Odontogênicos/genética , Germe de Dente/química , Fatores de Transcrição/genética , Diferenciação Celular/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Proteínas Ricas em Prolina do Estrato Córneo/genética , Desmogleína 1/genética , Epitélio/química , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Humanos , Queratina-4/genética , Queratinócitos/fisiologia , Proteínas com Homeodomínio LIM/genética , Família Multigênica/genética , Proteína Relacionada ao Hormônio Paratireóideo/genética , Fatores de Transcrição SOXB1/genética , Proteína Homeobox PITX2RESUMO
INTRODUCTION: Ameloblastomas and keratocysts are the most frequent epithelial odontogenic tumors of the jaws. They have a high recurrence rate. This retrospective study reviews the features of ameloblastomas operated on in our unit from 1994 to 2007. PATIENTS AND METHODS: The studied parameters were sex, ethnic origin, age at diagnosis, clinical signs, radiographic presentation, site distribution, histological type, treatment, and follow-up records. RESULTS: One hundred and sixteen patients were included (with 239 surgical samples). The mean age was 36 years, with a majority of Europeans, 60% of multilocular radiolucent lesions with root resorption, mandibular location (93%). Twenty-one percent of the patients presented with an impacted tooth, the third molar in 79% of cases. Fifty percent of the lesions were from 5 to 13cm in length, 10% longer than 13cm. The most common histological type was follicular ameloblastoma. Patients were treated by enucleation in 82% of cases and radical mandibular resection with reconstruction in 11% of cases. The follow-up was documented for 96% of the patients with a 44% recurrence rate. Seventy-four percent of patients with a double recurrence presented with a "follicular" ameloblastoma. DISCUSSION: We prefer a well-performed enucleation which preserves surrounding bone. The high rate of follicular type recurrence should more systematically lead to a combined treatment: periostectomy and tooth extraction. Our data was compared with previously published large series.
Assuntos
Ameloblastoma/cirurgia , Neoplasias Maxilomandibulares/cirurgia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Ameloblastoma/diagnóstico , Ameloblastoma/epidemiologia , Ameloblastoma/etnologia , Criança , Feminino , Seguimentos , Humanos , Neoplasias Maxilomandibulares/diagnóstico , Neoplasias Maxilomandibulares/epidemiologia , Neoplasias Maxilomandibulares/etnologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Estudos Retrospectivos , Fatores de Tempo , Adulto JovemRESUMO
This study describes polymorphism in Theileria annulata, an intracellular protozoan parasite of bovine leucocytes and red blood cells. Fifty-three different stocks of T. annulata, isolated from 17 sites (districts) in Tunisia, have been characterized by anti-parasite monoclonal antibody (MAb) reactivity, glucose phosphate isomerase (GPI) isoenzyme electrophoresis, and Southern blotting with two genomic DNA probes. These appears to be considerable diversity amongst T. annulata stocks from Tunisia, no two isolates being identical, even those from animals on the same farm. Two distinct antigenic populations were detected by MAb 7E7. They were defined by negative and positive cells in the indirect fluorescent antibody test. The percentage of positive cells in different isolates ranged between 0 and 100%. The population variation seen by GPI analysis and DNA probes was greater; 7 different GPI phenotypes were identified amongst the stocks studied, while DNA probes T. annulata Tunis (TaT) 17 and 21 detected up to 5 different variants. The majority of isolates were shown to contain more than one parasite population, the number of variants per isolate ranging from 1 to 4. No correlation between particular parasite phenotypes or genotypes and their geographical site of isolation was observed. Selection of parasite populations in vivo and in vitro is also discussed.