11 resultados para COX-2 expression
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Actinic cheilitis (AC) is a potentially malignant disorder which affects the lip vermilion and results from chronic exposure to sunlight. Currently, it is not possible to predict which cases of AC may progress to squamous cell carcinoma, and therefore, some biomolecular markers have been researched. Cyclooxygenase 2 (COX-2) is an enzyme associated with inflammatory response which is overexpressed in oral cancer; however, little is known about the role of this protein in actinic cheilitis. About the treatment of this lesion, currently available therapeutic modalities to AC may cause cytotoxic effects and deleterious results to patients. Therefore, the aim of this study was to evaluate the immunoexpression of COX-2 in AC of different risks of malignant transformation and analyse, through clinical follow-up, the efficacy of diclofenac sodium 3% gel in the treatment of this condition. Epithelial immunoexpression of COX-2 was analysed semi-quantitatively in 90 cases of AC classified as low risk (n = 55) and high risk (n = 35) of malignant transformation, in which the scores were assigned: (0) 0 to 5% of positive cells - Negative; (1) 6 to 30% of positive cells - Low expression; (2) 31 to 100% of positive cells - High expression. The chi-square test of Pearson was conducted to verify possible associations between immunoexpression of COX-2 and histologic grade of actinic cheilitis. The weighted kappa coefficient denoted a good interobserver agreement (0.677). Nineteen patients diagnosed with AC were instructed to perform topical application of the gel three times a day for a period of 90 days. In each biweekly visit, a follow-up record was accomplished through digital photographs and after treatment was completed, two researchers analysed all the images to assess clinical aspects of the lip. Furthermore, tolerability to the drug and patient satisfaction after treatment were evaluated. COX-2 was overexpressed in 74.4% of AC cases. Both low and high-risk groups revealed predominance of score 3, followed by scores 2 and 1. There was no significant association (p = 0.315) between COX-2 expression and histological grading. Among the total number of participants of this clinical study, ten showed total remission of all clinical features of the lesion and three had partial improvement of these characteristics. One participant presented worsening of the clinical condition. In five cases, the treatment was discontinued due to development of mild adverse effects at the site of gel application. Regarding analysis of satisfaction and tolerability to the drug, most patients were fully satisfied with the therapy (n = 11) and reported that the drug was not irritating to the lips (n = 9). Our study demonstrates that high expression of COX-2 is common in AC; however, this protein was not associated with malignant transformation risk of the analysed cases. Topical application of diclofenac sodium 3% gel provided a convenient and well tolerated approach in most cases, and may be a promising alternative for the treatment of actinic cheilitis.
Resumo:
The aim of this study was determine whether an association exists in the gum tissue between the expression of markers of tissue hypoxia (HIF-1α and GLUT-1) with a marker of inflammatory activity (COX-2) and a marker of collagen degradation (EMMPRIN). Was performed immunohistochemistry with antibodies specific for these markers on 60 samples of gingival tissue divided into two groups: gums (n = 26) and gingivitis (n = 34) and expression was analyzed in the epithelial tissue and connective tissue . The reactivity epithelial for COX-2 was observed in only two cases as the HIF-1α, GLUT-1 and EMMPRIN was strongly expressed in the epithelial basal layer and the immunostaining was gradually decreased as the cells away from this layer, and negative in the region suprabasal in most specimens. In connective tissue, and HIF-1α EMMPRIN were strongly positive for most cases analyzed as GLUT-1 was negative in most cases. Immunostaining for COX-2 showed an association with gingival inflammatory infiltrate. The expression of EMMPRIN, HIF-1α and GLUT-1 in normal gums confirms the physiological role of these markers, however there was no association with tissue inflammation. Given the findings we can conclude that the inflammatory changes installed in frames of chronic gingivitis may not be sufficient to activate the factors of hypoxia to levels that can be quantified by immunohistochemical analysis, in addition, the findings are not conclusive in relationship to involvement of EMMPRIN in the secretion of MMPs to degrade collagen in the frames of gingivitis. We suggest the use of technical analysis and quantification of RNA of EMMPRIN and MMPs in order to determine whether collagen degradation observed in gingivitis suffers or not, significant influence of EMMPRIN for secretion and activation of MMPs
Resumo:
Squamous cell carcinoma is the most common malignant neoplasm in the oral cavity, accounting for more than 90% of all malignancies in this location. Cyclooxygenases (COX s) are key enzymes on arachidonic acid metabolism and prostaglandin synthesis, being expressed basically in two forms: the constitutive (COX-1) and the inducible (COX-2). Increased levels on the expression of COX-2 have been implicated in the pathogenesis tumor progression of various forms of human cancer, including oral squamous cell carcinoma, some of what suggesting a possible interaction between COX-2 and the protein expressed by the tumor suppressor gene p53, mutated in more than 50% of all human cancers. The mean of the present research consisted in analyze the correlation between the expression of COX-2 and p53, at the protein level, as well as evaluate the difference on the expression of these two proteins with the histological grading of malignancy. 34 cases of oral squamous cell carcinoma were selected and graded according to the histological grading system proposed by Bryne (1998) and the labeling indexes (LI s) for COX-2 and p53 evaluated using immunohistochemistry method. The results revealed that COX-2 was expressed in increased levels in most of the specimens, although there was no statistic significant correlation between LI s from COX-2 and p53 (p>0.05), and there were no statistical differences on the expression of these proteins between tumors of high and low grade of malignancy (p>0.05). Interestingly, the expression of COX-2 and p53 was detected in fragments of dysplastic oral epithelium adjacent to tumor areas, on basal and suprabasal layers. The absence of statistical correlation between the expression of COX-2 and p53 proteins do not rule ot the existence of a relation between them, were it may reflect the diversity of regulatory pathways between both, different direct and indirect inhibitory effects of COX-2 over p53, as well as the wide range of activation macheenisms for COX-2 and mutational status of the p53 gene Another conclusion point that the increased expression of COX-2 observed in oral squamous cell carcinomas suggest a role for this protein in the processes of pathogenesis and tumoral evolution of this malignant neoplasm
Resumo:
Ameloblastoma and adenomatoid odontogenic tumor are odontogenic tumors arising from the odontogenic epithelium with distinct clinical behavior. In attempt to comprehend the interaction between the odontogenic tumor cells and the extracellular matrix, the present work evaluated and compared the immunohistochemical expression of the matrix metalloproteinases-1 (MMP-1), -2 (MMP-2) and -9 (MMP-9) in 20 cases of ameloblastoma and 10 adenomatoid odontogenic tumor. MMP-1 exhibited exuberant expression in the parenchyma and in the stroma of both studied tumors, while the MMP-2 showed varied expression with about of 80% and 60% of the neoplastic cells exhibiting positivity in the ameloblastoma and adenomatoid odontogenic tumor, respectively. With relation to the MMP-2 expression by the mesenchymal cells, it was observed that 65% of the ameloblastoma and 80% of the adenomatoid odontogenic tumor were positive. The immunoreactivity of MMP-9 was detected in all studied cases, although its expression had occurred predominantely in less than 50% of the parenchyma cells of the ameloblastoma, while in about of 60% of the adenomatoid odontogenic tumor more than 50% of cells were positive. The mesenchymal cells were positive to MMP-9 in 65% of the ameloblastoma and in 80% of the adenomatoid odontogenic tumor, respectively. Statistically significant difference was observed to the MMP-1 expression with relation to MMP-2 and MMP-9 in the ameloblastoma (p < 0.001). It was not possible to perform statistical analysis to the cases of adenomatoid odontogenic tumor, however there was a tendency toward a differential expression of the MMP-1 with relation to other studied MMPs. These results suggest that MMP-1, - 2 and -9 are implicated in the growth and progression of both tumors analyzed as well as the more pronounced participation of the stroma in the ameloblastoma could together to be related to the higher clinical aggressiveness
Resumo:
Bone morphogenetic proteins (BMPs) are cytokines involved in proliferation and angiogenesis of many kind of human cancer. The present study analyzed the immunohistochemical expression of BMP-2, BMPR-II, BMPR-IA and endoglin (CD105) and their relationship with the biological behavior and local angiogenesis in tongue oral squamous cells carcinoma (SCC). The sample consisted of 25 cases of tongue SCC without metastasis, 25 tongue SCC with metastasis and 25 cases of Inflamatory Fibrous Hyperplasia (IFH).The histological grade of malignancy proposed by Bryne (1998), adapted by Miranda (2002) was used to classify all tongue SCC cases. Score 0 was attributed to absent-weak immunoexpression and score 1 for strong immunostaning and pattern of distribution was focal or diffuse. Microvessel counts (MVC) was established for CD105. Most of the patients with tongue SCC was male. The principal age in tongue SCC without metastasis was over 65 years and in tongue SCC with metastasis was between 45-65 years. There were predominance of stage II in TNM and in the specimens with high-grade, independent of studied group. For BMP-2, 56% of tongue SCC without metastasis and 72% tongue SCC with metastasis exhibited score 1 while the IFH showed secore 0 in 72% of the cases, with statistical association (p=0,007). Considering the BMPR-II, 52% of tongue SCC without metastasis exhibited score 0; 56% tongue SCC with metastasis and 60% IFH showed score 1. The majority cases of BMPR-IA demonstrated score 1 and 100% of CD105 exhibited strong immunoexpression in tongue SCC. Regarding the pattern distribution, it was noted a tendency to diffuse pattern for the proteins in all groups. The means of MVC were similar in tongue SCC without metastasis (32,91) and in tongue SCC with metastasis (32,05), however existed statistical difference with IFH (p<0,001). There was statistical association of BMP-2 expression with BMPR-II (p=0,008), BMPR-IA (p=0,006) and CD105 (p=0,046). An association between TNM and BMP-2 immunoexpression and their receptors was not detected, nevertheless this association was found with MVC (p=0,047) whose averages were higher for the stages II (35,97) e IV (35,69). No association between histological grading and these proteins was observed. This study suggests that the superexpression of BMP-2 signaling pathways acts on cell proliferation in tongue SCC and can be implicated with more invasive potential. Additionaly, the CD105 is a potent biological marker of neovascularization in this neoplasm and their association with BMP-2 and BMPR-IA receptor, showed that this type of cancer in BMP-2 is presented as pro-angiogenic in the metastatic process
Resumo:
Periodontal diseases, highly prevalent disease in worldwide population, manifest primarily in two distinct entities: plaque-induced gingivitis and periodontitis. Periodontitis is a chronic inflammatory disease characterized of different levels of collagen, cementum, and alveolar bone destruction. Recent experimental studies demonstrated anti-inflammatory and antirreabsortive effect of antihypertensive agents of the angiotensin II receptor blockers class on periodontal disease. The aim of this study was to evaluate the effects of azilsartan (AZT), a potent inhibitor of the angiotensin II receptor which has minimal adverse effects on bone loss, inflammation, and the expression of matrix metallo proteinases (MMPs), receptor activator of nuclear factor kB ligand (RANKL), receptor activator of nuclear factor kB (RANK), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2), and cathepsin K in periodontal tissue in a rat model of ligature-induced periodontitis. Male Wistar albino rats were randomly divided into 5 groups of 20 rats each: (1) nonligated, water; (2) ligated, water; (3) ligated, 1 mg/kg AZT; (4) ligated, 5 mg/kg AZT; and (5) ligated, 10 mg/kg AZT. All groups were treated with water or AZT for 10 days. Periodontal tissues were analyzed by morphometric exam, histopathology and immunohistochemical detection of MMP-2, MMP-9, COX-2, RANKL, RANK, OPG, and cathepsin K. Levels of IL-1b, IL-10, TNF-a, myeloperoxidase (MPO), and glutathione (GSH) were determined by ELISA. Treatment with 5 mg/kg AZT resulted in reduced MPO (p˂0.05) and IL-1b (p˂0.05) levels and increased in Il-10 levels (p˂0.05). It was observed a reduced expression of MMP-2, MMP-9, COX-2, RANK, RANKL, cathepsin K, and a increased expression of OPG in the animals subjected to experimental periodontitis and threated with AZT (5 mg/kg). Conclusions: These findings suggest an anti-inflammatory and anti-reabsortive effects of AZT on ligature-induced periodontitis in rats.
Resumo:
Intestinal Mucositis is inflammation and/or ulceration of mucosa of the gastrointestinal tract caused by anticancer therapies. Histologically, villous atrophy, damage to enterocytes and infiltration of inflammatory cells. Methotrexate (MTX) is a compound that depletes dihydrofolate pools and is widely used in the treatment of leukemia and other malignancies. The aim of this study was to evaluate the effect of Olmesartan (OLM), an angiotensin II receptor antagonist, on an Intestinal Mucositis Model (IMM) induced by MTX in Wistar rats. IMM was induced via intraperitoneal (i.p.) administration of MTX (7 mg/kg) for three consecutive days. The animals were pretreated with oral OLM at 0.5, 1 or 5 mg/kg or with vehicle 30 min prior to exposure to MTX, for three days. Small intestinal (duodenum, jejunum and ileum) homogenates were assayed for levels of the IL-1β, IL-10 and TNF-α cytokines, malondialdehyde and myeloperoxidase activity. Additionally, immunohistochemical analyses of MMP-2, MMP-9, COX-2, RANK/RANKL and SOCS-1 and confocal microscopy analysis of SOCS-1 expression were performed. Treatment with MTX+OLM (5 mg/kg) resulted in a reduction of mucosal inflammatory infiltration, ulcerations, vasodilatation and hemorrhagic areas (p<0.05) as well as reduced concentrations of MPO (p<0.001) and the pro-inflammatory cytokines IL-1β and TNF-α (p<0.01), and increase antiinflammatory cytosine IL-10 (p,0.05). Additionally, the combined treatment reduced expression of MMP-2, MMP-9, COX-2, RANK and RANKL (p<0.05) and increased cytoplasmic expression of SOCS-1 (p<0.05). Our findings confirm the involvement of OLM in reducing the inflammatory response through increased immunosuppressive signaling in an IMM. We also suggest that the beneficial effect of Olmesartan treatment is specifically exerted during the damage through blocking inflammatory cytosines.
Resumo:
GURGEL, Bruno Cesar de vasconcelos.Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos. 2003.97f. Dissertaçao (Mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba. Piracicaba, 2003. Disponivel em:
Resumo:
A periodontite é uma doença crônica inflamatória mediada por marcadores inflamatórios, tais como as citocinas: IL-1β, IL-10 e TNF-α, que provoca a destruição dos tecidos gengivais e osso alveolar, causando perda de inserção dentária e posterior perda dental. A perda óssea é causada pela ativação de prostaglandinas oriundas do ácido araquidônico, através da ação da enzima ciclooxigenase 2 (COX-2), promovendo a liberação de enzimas proteolíticas, as metaloproteinases de matriz, principalmente a MMP-2 e MMP-9, que promovem reabsorção óssea. Além disso, ocorre o desequilíbrio entre a ação de RANKL e OPG, havendo uma maior ativação de RANKL, e por consequência a maior ativação de osteoclastos e maior reabsorção óssea. Mediadores inflamatórios e espécies reativas de oxigênio (ROS) produzidos localmente possuem potencial para disseminar na corrente sanguínea e iniciar ou exacerbar doenças sistêmicas como as cardiovasculares. O tratamento atual da doença consiste em terapêutica local, mas a necessidade de estudos sobre fármacos de atuação sistêmica culminou nesta pesquisa, que realizou a avaliação dos fármacos: atorvastatin, carvedilol, olmesartan e telmisartan, quanto a sua ação anti-inflamatória sobre a doença periodontal induzida por ligadura em ratos Wistar. Os animais foram divididos em 5 grupos, para cada fármaco, separadamente: (NL) grupo não ligado, (L) grupo ligado sem tratamento, (1mg/Kg) grupo ligado que recebeu dose de 1mg/Kg de fármaco, (5 ou 6 mg/Kg) grupo ligado que recebeu dose de 5 ou 6 mg/Kg de fármaco, (10 mg/Kg) grupo ligado que recebeu dose de 10mg/Kg de fármaco. Foram realizadas avaliações: histopatológica, perda óssea alveolar, imuno-histoquímica (para COX-2, MMP-2, MMP-9, RANK-L, RANK e OPG), e ELISA (para mieloperoxidase, glutationa, malonaldeído e as citocinas: IL-1β, IL-10 e TNF-α). Os grupos tratados com olmesartana a 6 mg/Kg, e atorvastatin, carvedilol e telmisartan a 10mg/Kg, mostraram diminuição da perda óssea, redução de: MPO, MDA, IL-1β, TNF-α, MMP-2, MMP-9, COX-2, RANKL/RANK, e aumento na expressão da OPG e da IL-10.
Resumo:
Except the non-melanoma skin tumors, colorectal cancer is the second most common in the Southeastern Region of Brazil, the third most common in the Southern and Central Regions. It is also the forth most common in the Northern Region and it is the fifth one in the Northeastern. To assess pathological and clinical variables of colorectal Cancer is crucial to know the possible conclusions for the survival of patients and point out the characteristics in the progress of tumor, such as the profile of tumor invasion and its angiogenesis. This work focuses on analyzing clinically and pathologically some settings in colorectal cancer patients (CRC) in the city of Natal and its countryside through those variables as parameters of prognosis and determine the level of protein expression, for instance: E-cadherin (E-cad), beta- -catenin (β-cat), galectin-3 (gal-3), matrix metalloproteinases (MMP) 2 and 9 and vascular-endothelial growth factor alpha (α VEGF) in the tumor tissues. A retrospective study was done in colorectal cancer cases in the regions of Rio Grande do Norte state from 1995 to 2005, specifically in Natal city/RN/Brazil. The pathological and clinical variables, such as: age, gender, ethnicity, lifestyle, family history, the location of the primary tumor, level of differentiation, TDM staging, modified Dukes’, treatment and survival were analyzed. The pathological and clinical data were collected from medical records through a specific form and were filed on Excel. A total of 534 patients were selected from the Pathology Department file in this institution, however, 176 patients were excluded. 358 patients were included for Epidemiological analysis and its clinical and pathological correlations were selected. 180 patients were also selected for histological and immunohistochemical studies. The tumor progression of these selected proteins mentioned before were analyzed. The Paraffin blocks of these samples were treated by Microarray Tissue technique and its blades subjected to immunohistochemistry to test the intensity of these proteins in tumor tissues. The results of this analysis were correlated with clinicopathologic variables of patients. Statistical analysis using the chi-frame Pearson test and analysis of midlife by Kaplan-Meier curve was also utilized. P values < 0.05 were considered statistically significant. The average age of our sample was 58.8 years and 51.7 % were female. Alcohol consumption has increased by 1.71 time the risk of death by CCR (p = 0.034) and tobacco consumption increased 2.7 times the chance of developing tumors of high TNM stage (p = 0.001). Cancer patients had a family history of 3,833 times the chance of developing the CCR (p = 0.002). The expression of MMP-2 showed a significant association with tumors of high TNM stage (p <0.046) and mortality (p = 0.041). The α VEGF expression had statistically significant correlation with high TNM stage (p <0.009), degree of cell indifferentiation (p <0.025) and mortality (p <0.035). Expressions of E-cadherin and beta-catetina demonstrated tumor linked to high TNM stage (p = 0.0001) and Dukes› modified (p = 0.05), lesions in the rectum (p = 0.03 and p = 0.007, respectively), smoking (p = 0.05) and indifferentiation (p = 0.001). The expression of Gal-3 showed statistical significance with high TNM stage of patients (p = 0.01), smokers (p = 0.01), alcohol drinking (p = 0.03), indifferentiation (p = 0.0001) and mortality (p = 0.0001). Based on the results, therefore, we could realize that lifestyle and family history had correlation in the CCR prognosis, as well as MMP-2 expression, MMP-9, VEGF alpha, E-cadherin, Beta-catenin and Galectin-3 were important prognostic markers in tumor progression in colorectal cancer.
Resumo:
GURGEL, Bruno Cesar de vasconcelos.Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos. 2003.97f. Dissertaçao (Mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba. Piracicaba, 2003. Disponivel em: