RESUMO
Gastrointestinal stromal tumor is the most common clinically significant mesenchymal neoplasm of the gastrointestinal tract. The expression of the intermediate filament cytokeratin in gastrointestinal stromal tumor is not frequently reported in the literature. The aim of this study was to investigate the immunohistochemical expression of several types of cytokeratin in a large number of cases (n=687), including a pan-cytokeratin marker (AE1/AE3 cocktail antibodies), high-molecular weight cytokeratins (34ßE12 antibody), and individual cytokeratins 8 (35ßH11 and CAM5.2 antibodies), 7, 14, and 20. Ki-67 antigen was used for the determination of cell proliferation index, and the correlation between Ki-67 and cytokeratin expression was evaluated. Cytokeratin expression was also correlated with several clinicopathologic parameters. The expression of pan-cytokeratin was observed in 24 (3.5%) cases, with variable intensity. Only 1 of 687 (0.1%) cases showed cytokeratin 14 expression. All 687 cases revealed no expression of high-molecular weight cytokeratins, cytokeratins 7, 8, and 20. No significant statistical association was found between AE1/AE3 immunoreactivity and several clinicopathologic parameters, including sex, tumor location and size, cell morphology, mitotic count, risk of aggressive behavior, and Ki-67 antigen cell proliferation index. However, statistical correlation between AE1/AE3 immunoreactivity and a higher age at diagnosis was detected. These results show that cytokeratin expression is not frequent in gastrointestinal stromal tumor, but caution is necessary to avoid erroneous diagnoses.
Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias Gastrointestinais , Regulação Neoplásica da Expressão Gênica , Queratina-14/biossíntese , Queratina-20/biossíntese , Queratina-7/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antineoplásicos/química , Proliferação de Células , Feminino , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/patologia , Humanos , Imuno-Histoquímica/métodos , Imuno-Histoquímica/normas , Antígeno Ki-67/biossíntese , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
BACKGROUND: Physiological root resorption differentiates primary from permanent teeth. The understanding of what protects and regulates root resorption might help to develop therapies to its control. AIM: To verify the presence and distribution of ECRM and the expression of CK14, OPG, TRAP and COX-2 in the periodontal ligament (PDL) of human primary and permanent teeth. Design. Eight primary teeth undergoing physiological or pathological root resorption and 4 permanent teeth were immunohistochemically processed for CK14, TRAP, COX-2 and OPG expression. RESULTS: PDL from primary and permanent teeth showed similar morphological features; however, fewer ECRM clusters and higher immunoreactivity to CK14 were found in primary PDL. In permanent teeth, ECRM were distributed along the entire PDL tissue. Howship's lacunae were found only in primary teeth, associated with the presence of TRAP-positive cells and increase in COX-2 expression. OPG expression in primary PDL was detected in nonresorptive cervical areas and in lacunae showing reparative tissue. It was observed higher expression of OPG in all permanent teeth when compared to primary specimens. CONCLUSIONS: It may be concluded that PDL from primary teeth shows less ECRM clusters and lower expression of OPG. These features may be associated with lower protection against root resorption in primary teeth.