Expressão imuno-histoquímica das integrinas α2ß1, α3ß1, e α5ß1, em mucosa oral normal, hiperplasia fibroepitelial inflamatória oral e displasia epitelial oral

The objective of this study was perform by the streptoavidin-biotin technique an immunohistochemical analysis of α2β1, α3β1e α5β1 integrins in 11 normal oral mucosa (NOM), 16 oral inflammatory fibroepithelial hyperplasia (OIFH) and 25 oral epithelial dysplasia (OED) (16 mild, 2 moderates and 7 severe), to determine if exists qualitative alteration in the expression of these integrins and if this guard relation with the oral epithelial modifications. It was observed that for the α2β1 integrin the majority of the sample showed a predominantly intense labeling diffusely distributed in the intercellular contacts and the cytoplasm of cells of the basal and suprabasal layers, without difference of this profile between the different types of specimens, however with a trend to weak or loss of expression in 21.1% of the OEDs, being all the specimens that had not expressed this heterodimer, severe OEDs. For the α3β1 integrin the majority of the sample showed a weak or absent labeling in basal layer. The α5β1 integrin showed a predominant strong diffuse labeling in the intercellular contacts and cytoplasm in the suprabasal layer, with difference only in the labeling intensity between the types of specimens, inhabiting this difference in the OEDs, where 12 (48%) specimens had shown a weak labeling. It was concluded that the evaluated integrins can be involved in the cell-cell, cell-ECM interactions modulating the cellular differentiation and maintenance of the epithelial structural arrangement. The variable expression of the α5β1 integrin in the OEDs, could suggest, respectively, a role of this molecule in the cellular survival, with intention to perpetuate the modified phenotype in these lesions, or a suppressor role on the modified phenotype due to lack of interaction of this molecule with the fibronectina of the MEC

Expressão imuno-histoquímica do cd8, foxp3, Tgf β, tnf α e nf-кb em displasias epiteliais e Carcinomas epidermóides orais

The Oral Epithelial Dysplasia (OED) is the lesion that precedes or co-exists with the Oral Squamous Cell Carcinoma (OSCC), presenting molecular and/or histological similar alterations. The divergences about the malignization potential of OEDs and the role of inflammation in this process make hard the early diagnosis and evaluation of OSCCs aggressiveness. Thus, it became the goal of this study to evaluate the role of inflammation in oral carcinogenesis and tumoral aggressiveness. For this purpose a morphological study was performed in 20 OED cases and 40 OSCC cases to detect the malignization potential of OEDs and the histologic malignancy grading (HMG) of OSCCs, analyzing superficial masses for dismorphism evaluation and the invasive front for evaluation of tumoral growing; and immunohistochemical, using anti-CD8, anti-FOXP3, anti-TGFβ, anti-TNFα and anti-NF-кB antibodies, comparing their with the types lesion, histological degree and intensity of the inflammatory infiltrate. The results were statistically significant for the parameters: cell maturity (p=0,0001), masses presence (p=0,038) and dismorphism (p=0,037), when associated to HMG. To compare the expression of the markers with the types lesion, a significantly higher expression of CD8 (p=0,001) and NF-кB (p=0,002) in the OED, and also a smaller expression of the epithelial TGFβ in the severe OEDs (p=0,011), without significant expression between OSCC degrees. By relating the expression of the studied markers with the inflammatory infiltrate intensity, a positive relation was observed with: inflammatory TNFα(p=0,003), epithelial TNFα and NF-кB (p=0,051 and p=0,004), in OEDs; and with CD8 (p=0,021) and TNFα (p=0,015) in conjunctive OSCCs; and a negative relation with epithelial TNFα (p=0,034) in OSCCs. No significant relation was found between FOXP3 with any of the studied variables. These findings lead to the conclusion that, the study of the invasive front is as important as the study of superficial masses for the evaluation of tumoral aggressiveness; the intensity of the inflammatory infiltrate has no use as a parameter for prognostic evaluation of OSCC in routine exams, but, the molecular events detected in this study may be necessary to give basis for determining the malignant potential in OEDs and aggressiveness in OSCCs

Análise de células t regulatórias foxp3+no líquen plano oral

T regulatory cells have the function of controlling immune responses and maintaining self-tolerance. The FoxP3 has been considered the most specific marker for Treg cells. The aiming of this paper was to evaluate the immunoexpression of FoxP3 in the inflammatory infiltrate from oral lichen planus (OLP) and to compare it with the infiltrate in fibrous inflammatory hyperplasia (FIH) and then, between reticular and erosive forms of OLP. The samples were composed by 32 cases of OLP (17 reticular and 15 erosive) beyond 10 cases of FIH that were submitted to immunohistochemistry staining for FoxP3. Localization of the staining was classified in underepithelial and intraepithelial and the amount of FoxP3+ cells was evaluated through cells counting in 10 consecutive fields, at 400x power magnification. The values were expressed in mean ± standart deviation, and submitted to statistical tests with 5% of significance level. It was observed a statistical significant difference in the amount of FoxP3+ Treg cells between the two combined forms of OLP (1,6 ± 2,2) and the FIH (0,5 ±0,4) (P<0,05). This maybe could be explained by immunological mechanism of OLP, which involves a permanent antigenic induction likely with consequent perpetuation of lesion, eliciting the proliferation and constant recruitment of Treg cells. Otherwise, FIH presents a different etiopathogenesis, in which there is also generation of a variable inflammatory infiltrate, however qualitatively distinct from that seen in OLP. The erosive form of OLP exhibited a greater number (1,7 ± 2,4) of FoxP3+ Treg cells than reticular form (1,5 ± 2,1). These alterations could have relation with the great disease activity verified in erosive OLP, or also, with abnormalities in the regulatory function of Treg cells that could cause the increase observed. Considering the capacity already well established in the literature, both about Treg cells in modulating immune responses, as in the oral mucosa in showing great potential for regeneration, it is suggested that the possibility of development and implantation of immunotherapeutic strategies that regulate the frequency and function of these cells, may help in future treatment of immune-mediated inflammatory diseases such as OLP

Análise comparativa da imunoexpressão das proteínas hmlh1 e hmsh2 em carcinomas epidermóides de lábio inferior e queilites actínicas com graus variados de displasia

Lip squamous cell carcinoma (SCC) may develop from a premalignant condition, actinic cheilitis (AC) in 95% of the cases. Both premalignant and neoplastic lip diseases are caused mainly by chronic exposure to the ultraviolet component of solar radiation, especially UVB. This exposure causes disruption of the cell cycle and damage to DNA repair systems, like mismatch repair, altering proteins repair as hMLH1 and hMSH2. This research aimed to investigate the immunohistochemical expression of hMLH1 and hMSH2 proteins in lower lip SCCs and ACs, providing additional information about carcinogenesis of the lower lip. The sample consisted 40 cases of ACs and 40 cases of lower lip SCCs. Histological sections of 3 μm were submitted to immunoperoxidase method, for immunohistochemical analysis of lesions were counted in 1000 cells (positive and negative), data were evaluated both in absolute numbers and percentage of immunostained cells, the latter by assigning scores. Associations of the variables and comparative analysis of biomarker expression were performed by Fisher s exact and Pearson s chi-square, "t" student, one-way ANOVA, Mann- Whitney e Kruskal-Wallis tests. The level of significance was 5%. It was found that, in lower lip SCC, the mean of the proteins was higher in female patients (hMLH1= 369,80 + 223,98; hMHS2 = 534,80 + 343,62), less than 50 years old (hMLH1 = 285,50 + 190,65; hMHS2 = 540,00 + 274,79) and classified as low-grade malignancy (hMLH1 = 264,59 + 179,21; hMHS2 = 519,32 + 302,58), in these data only to sex, for hMLH1 protein, was statistically significant (p=0.034). Comparing the different lesions, we observed that for both hMLH1 and hMSH2 protein, the average of positive epithelial cells decreased as the lesion was graded at later stages. The ACs classified without dysplasia or mild dysplasia had the highest average of immunostained cells (hMLH1 = 721.23 + 88.116; hMHS2 = 781.50 + 156.93). The ACs classified as moderate or severe dysplasia had intermediate values (hMLH1 = 532,86 + 197,72; hMHS2 = 611,14 + 172,48) and SSCs of the lower lip had the lowest averages (hMLH1 = 255,03 + 199,47; hMHS2 = 518,38 + 265,68). There was a statistically significant difference between groups (p<0.001). In conclusion, our data support the hypothesis that changes in immunoexpression of these proteins is related to the process of carcinogenesis of the lower lip

Análise da resposta th17 em líquen plano oral

Th17 cells have been strongly associated with the pathogenesis of several autoimmune and inflammatory diseases. IL-17 and IL-23 are important cytokines associated with this lineage. The aim of this study was to analyze, through immunohistochemical methods, the immunoexpression of IL-17 and IL-23 in the inflammatory infiltrate of oral lichen planus (OLP) lesion compared to that of inflammatory fibrous hyperplasia (IFH) and between clinical forms reticular and erosive of OLP. The sample included 41 cases of OLP, of which 23 were reticular and 18 erosive and 10 cases of IFH. The results were subjected to nonparametric statistical tests with a 5% significance level. In OLP lesions histomorphological analysis, the most common findings were: hyperparakeratinization, specimens with atrophic epithelium in erosive clinical form (p = 0.011), epithelial projections in most of reticular type of lesions, in addition Civatte bodies were identified in most samples of both clinical forms. For immunohistochemistry analysis, five fields with strong immunoreactivity for IL-17 and IL-23 were photomicrographed at 400x magnification, images were transferred to a computer where with ImageJ software®, lymphocytes that exhibited cytoplasmic immunostaining for these cytokines were counted. A mean was established after for each case. There was no statistically significant difference in the number of imunopositive lymphocytes for IL-17 and IL-23 among the group of OLP and IFH group, however a larger amount of lymphocytes imunopositive for IL-17 was found in the LPO group (p = 0.079) and significantly higher amounts of those lymphocytes were found in the erosive OLP when compared to the group of reticular OLP and IFH (p = 0.019). Furthermore, a marker epithelial immunopositivity for IL-17 was observed in OLP group. Although the results of this study do not permit the forceful assertion about the participation of Th17 lineage in OLP lesions, the findings of immunopositive lymphocytes counting for IL-17 and IL-23, which are potent proinflammatory cytokines, together with the the marked epithelial immunopositivity found for IL-17 in this study, suggest a possible role of this lineage in the pathogenesis of this disorder

Expressão Imuno-histoquímica da triptase em mastócitos nos Fibromas de Células Gigantes e Hiperplasias Fibrosas de Mucosa Oral

The giant cell fibroma is a benign neoplasm characterized by the presence of mono, bi or multinucleate cells, which can have a connection to the presence of mast cells. This research aims to analyze, descriptively and comparatively, the immunohystochemistry expression of the tryptase in mast cells of the giant cell f ibroma, f ibrous hyperplasia and samples of the normal oral mucosa. Thirty cases of giant cell fibroma, ten cases of fibrous hyperplasia and ten cases of normal oral mucosa were selected for the analysis of the immunohistochemistry expression, determination of the number of present mast cells, as well as their location and shape. It could be stated that there was a statistically signif icant difference (p<0,001) in relation to the quantity of mast cells among other samples analyzed where the giant cell f ibroma presented lesser quantity of mast cell and the hyperplasia showed higher concentration of this cellular type. Although the oral mucosa has presented a higher quantity of mast cells when compared to the giant cells fibroma, these were found in usual locations in the connective tissue in normal tissues. There could be noticed a statistically significant difference in relation to the number of non-granulated mast cells (p<0,001). On the areas of fibrosis, we could observe a statistically signif icant difference (p<0,006) among the samples. In relation to the present mast cells in perivascular location, no statistically signif icant difference was found. On the morphological analysis there was a predominance of oval mast cells. It was concluded that despite of the fact there was a lesser quantity of mast cells present in cases of giant cell f ibroma, they appeared to have a stronger relation to the present giant fibroblasts in this lesions, around 59,62%, being also evidenced a strong relation between these cells and the fibrosis areas in both cases of giant cell f ibroma and f ibrous hyperplasias and samples of normal oral mucosa, used as control group in our study, confirming, this way, the role of the mast cells as fibrinogenous inductor

Expressão Imuno-histoquímica das proteínas GLUT-1 e HIF-1α em lesões vasculares de mucosa oral

The correct histological diagnosis of vascular lesions in the oral mucosa is critical, especially in defining the treatment and prognosis, as some vascular lesions show spontaneous involution and others do not show such behavior. This study analyzed the expression immunohistochemistry of human glucose transporter protein (GLUT-1), in oral benign vascular tumors and to reclassify such lesions according to with his immunoexpression. In addition, we evaluated the immunohistochemical expression of hypoxia-inducible factor 1 alpha (HIF-1α), the main transcription factor involved in cellular adaptation to hypoxia. We analyzed 60 cases of benign oral vascular tumors: 30 cases with histological diagnosis of HEM and 30 cases of oral pyogenic granuloma (PG). The results of this research showed that of the 30 lesions initially classified as HEM, only 7 showed immuno-positivity for GLUT-1, remaining with the initial diagnosis. The remaining 23 were reclassified as vascular malformation (VM) (13 cases) and PG (10 cases). All cases in the sample with an initial diagnosis of PG were negative for GLUT-1, demonstrating the accuracy of histological diagnosis of these lesions. Concerning to the immunoexpression of HIF-1α, the Mann-Whitney test revealed a statistically significant difference between the cases of GP and MV (p = 0.002), where the median of GP (m=78) was higher than the MV (m=53). Based on these results, this study showed that a histological diagnosis alone is not always sufficient for the correct diagnosis of oral HEM and that HIF-1α participates in the pathogenesis of vascular lesions

Expressão imuno-histoquímica de IL-17, TGF-β1 e FOXP3 em ganulomas periapicais, cistos radiculares e cistos radiculares residuais

Periapical lesions are chronic inflammatory conditions of periradicular tissues considered direct consequences of infectious diseases resulting from pulp necrosis and subsequent progression to periapical region. The participation of the immune response and bone resorption in the formation of these lesions has been investigated, so that different cell types and cytokines have been identified as contributors to this process. In this perspective, this study aimed to evaluate the immunohistochemical expression of IL-17, TGF-β1 and FoxP3 in periapical granulomas (PGs), radicular cysts (RCs) and residual radicular cysts (RRCs), seeking a better understanding of the etiopathogenesis these periapicopatias. To this end, we selected 20 cases of GPs, 20 CRs and 10 RRCs to undergo morphological analysis and immunohistochemistry for biomarkers above, the latter being performed quantitatively using scores and average percentages of immunostaining for the analysis of IL-17 and TGF- β1, while for the FoxP3 were counted only the positive lymphocytes. The results showed statistically significant differences between TGF-β1 and FoxP3 imunoexpressions, in relation to the periapical lesions studied (p = 0.002, p <0.001, respectively) but not between IL-17 and these (p = 0.355). Furthermore, the analysis of lymphocytes FoxP3-positive revealed significant statistical differences in that refers to the intensity of inflammatory infiltrate (p = 0.003) and also regarding thickness of the epithelial lining (p = 0.009). Finally, it was observed in the case of PGs, strong positive correlation between the amount of FoxP3- positive lymphocytes and the immunohistochemical expression of TGF-β1 (r = 0.755, p<0.001), as well as moderate positive correlation between IL-17 and TGF-β1 imunoexpressions (r = 0.503, p = 0.024). Thus, we can conclude that interactions between Th17 and Treg cells seem to be established at the site of injury, suggesting the involvement of both pro-inflammatory and immunoregulatory cytokines in the pathogenesis of periapical lesions

Valor prognóstico de células TCD8+ E natural killer em carcinoma epidermóide oral e orofaringeano tratado com radioterapia e quimioterapia

The most common malignant neoplasm of the oral cavity and oropharynx are squamous cell carcinoma. Injuries to the same stage and subjected to the same treatment protocol have sometimes different evolutionary courses. The scope of this study was to investigate, through a retrospective cohort, associations between the number of CD8 + T cells and natural killer, identified immunohistochemically in the inflammatory infiltrate in a series of cases of oral squamous cell carcinoma and orofaringeano, and the level of tumor response to radiotherapy and chemotherapy, overall survival and relapse-free survival of patients. We identified 54 patients with unresectable disease were treated exclusively with radiotherapy and chemotherapy. The median follow-up was 22 months. The sample was characterized by the predominance of male subjects, median age 60 years, all were smokers. The most frequent site was the tongue and 81.5% were in stage IV. Patients with disease in the oral cavity had a worse response to treatment (p = 0.006), worse relapse-free survival (p = 0.007), worse overall survival (p = 0.007). The advanced T stage was shown a negative prognostic factor (p= 0.006) for the clinical treatment response made. Immunohistochemistry was performed to select CD8 + cells (anti-CD8) and NK cells (anti-CD57). Lymphocytes positive and negative markings were counted using the program ImageJ ®. Two groups were created for each marking evaluated: Group I patients with more than 50% cells positive, Group II: less than 50% of labeled cells. For CD8 + cells detected in 38 (70.3%) of Group I were CD8 + and 16 (29.7%) Group II CD8 +. For NK cells, 26 (48.15%) Group I NK and 28 (51.85%) Group II NK. Regarding the clinical response to treatment, we observed that 39% of patients achieved a complete response and 25.9% remained without recurrence at the end of follow-up. These results were better in Group I CD8 + (p = 0.2). Identified that 72.2% of patients progressed to death, this finding had no association with the immunohistochemical data. There was no statistically significant differences between the number of CD8 + and NK cells and the ability of tumor response to radiotherapy and chemotherapy, or with overall survival and relapse-free survival of patients. However, especially in relation to a learned response, we found that this group of patients with advanced disease have a low count of CD8 + T cells active. Believing in the role that the immune response plays in the local fight against neoplastic cells, however, our results do not support the use of quantitative analysis of CD8 + T cells and NK cells as a prognostic factors for oral squamous cell carcinoma and oropharynx

Papilomavírus humano (HPV) e células de Langerhans em carcinoma epidermóide oral

The Human Papillomavirus (HPV) has been strongly implicated on development of some cases of oral squamous cell carcinoma (OSCC). However, the immunological system somehow reacts against the presence of this virus. Among the cells involved on such mechanism of defense detaches the Langerhans cells (LC), which are responsible for processing and presenting antigens. The purpose of this study was to evaluate the immunohistochemical reactivity for Langerhans cells between HPV positive and HPV negative OSCC, as well as, the relation of the immunoreactivity for this cells and the histological grading of malignancy proposed by Bryne (1998) and modified by Miranda (2002). Additionally, HPV infection was evaluated in relation to sex, age, lesion localization and histological grading of malignancy. In the total, 27 cases of OSSC were evaluated, 09 of them HPV positive and 18 HPV negative. Anti S-100 antibody was utilized for the immunohistochemical labelling, followed by the counting of LCs in 5 highpower fields (400x). No statistically significant difference was verified between the variables sex, age, lesion localization, histological grading of malignancy and HPV presence in OSSC. There was neither association between the immunohistochemical labeling for LCs (S-100+) and HPV infection nor correlation between the quantity of LCs labeled and the histological grading of malignancy of OSSC. The results suggest that despite the absence of statistically significant difference, the presence of HPV in such cases of OSCC can alter the immunological system, particularly the Langerhans cells

Avaliação imuno-histoquímica da BMP-2, BMP-4 e seus receptores (BMPRIA e BMPRII) em ameloblastomas e tumor odontogênico adenomatóide

BMPs are components superfamily ligands transformation growth fator-β (TGF-β) secreted into the extracellular environment, with mechanisms of intercellular communication through specific ligands and receptors in various target cells, being recognized for its influence in osteogenic induction, also play an important role in tissue homeostasis, cell proliferation, differentiation control , in addition to being present in the development of various malignancies. The aim of this study was to compare the immunohistochemical expression of BMP-2, BMP-4 and its receptors BMPRIA and BMPRII in cases of ameloblastoma and adenomatoid odontogenic tumor. The sample consisted of 20 cases of solid ameloblastoma (SA), 10 cases of ameloblastoma unicystic (UA) and 16 cases of adenomatoid odontogenic tumor (AOT). The expression of BMPs and their receptors was evaluated in the parenchyma and stroma of lesions, establishing the percentage of immunopositive cells (0 - negative; 1-1 % to 10 % of cells positive; 2 - 11% to 25% of positive cells; 3 - 26% to 50% of cells positive; 4 - 51% to 75 % of positive cells; 5 - more than 75% positive cells). Analysis of the expression of BMP-2 revealed no statistically significant differences in parenchymal (p = 0.925) and stromal component (p = 0.345) between the groups, as well as BMP-4 (p = 0.873 / p = 0.131). In the epithelial component, SA and AOT had a higher frequency of score 5. In turn, all cases of UA were classified as score 5. The analysis of the stromal component showed no statistically significant difference between groups with respect to median scores BMPRIA positivity (p = 0.768) and BMPRII (p = 0.779). In the epithelial component of SA and UA, no statistically significant correlations between imunoexpression proteins analyzed were observed. In turn, the group of AOT, statistically significant positive correlations between the scores of expression of all studied proteins were found. In the stromal component, statistically significant positive correlations were found only in the SA group in BMP -4 and BMPRII (r = 0.476; p = .034), in the UA in BMP-4 and BMPRIA (r = 0.709; p = 0.022). The results of this study suggest that the BMPs and their receptors are involved in the development process odontogenic tumors. BMP-4, in turn, besides being present in odontogenic tumors have the capacity to form mineralized material.

Imunoexpressão do EGFR e da podoplanina em cistos radiculares e dentígeros

The radicular cysts (RCs) and dentigerous (DCs), despite having different etiologies, form a pathological cavity lined by epithelium, which grows due to the buildup of fluid inside, as the surrounding bone is reabsorbed and the epithelium will being induced to proliferate. The epithelial proliferation, which has been identified as one of the key processes in the growth of odontogenic cystic lesions, is influenced by growth factors such as EGFR (epidermal growth receptor factor) and podoplanin (PDPN), many of which may have its production stimulated mainly during inflammatory processes. The objective of this research was to evaluate and compare the immunohistochemical expression of EGFR and PDPN in 30 cases of RCs and 30 cases of DCs, semiquantitatively, in light microscopy, associating it with the degree of inflammation, cellular localization of immunostaining and with the immunostained epithelial layers. Data were statistically analyzed by Chi-square test and Fisher exact test, considering a significance level of 5 %. The results showed high immunoreactivity of both proteins in the lesions studied, only statistically significant difference was observed in immunostaining of PDPN (p=0.033), which proved higher in RCs. The other analyzed parameters showed no relevant significant differences. We conclude that, as EGFR and PDPN showed high immunoreactivity in cystic lesions analyzed, these proteins participate the pathogenesis of these lesions through the epithelial stimulation process, despite having different etiologies. Furthermore, it can infer that the higher immunostaining of PDNP in RCs that DCs showed no distinction indicator between the two lesions, regarding their etiologies, once this protein also showed a considerable expression in DCs, independent of the intensity of the inflammatory infiltrate

Avaliação da angiogênese em lesões de líquen plano oral e pênfigo vulgar

Oral lichen planus and pemphigus vulgaris are chronic diseases mucous membrane immune of unknown aetiology that can be observed affecting to the oral mucous. A relevant as regards neoplasies the role angiogenesis in the inflammatory chronic disease pathogenesis as it provides a substancial interest can be considered as being an activity diseases marker; besides being through specialised research of this angiogenic process to improve of understanding pathogenic mechanism. This research proposes to assess angiogenic active through of antibody immunohistochemistry expression antiCD34 antibody in 26 OLP of reticular cases, 14 OLP erosives cases, 18 of PV cases and 15 specimens of normal oral mucosa. The result was submitted non-parametric tests of 5% significance level. It is not statistically significant correlacion was seen regarding between average vessels. However, only be effectively observed the median of OLP cases was larger than pemphigus vulgaris in fact proved average larger than oral normal mucosa (p=0,280). Regarding the microvascular count of CD34 concerning clinic form oral lichen planus (reticular and erosion) increased emphasis is more cross-border average for the form erosion clinic. Despite of the statistic tests could not be more effective (p=0,720). Even though, the results of the research is not sufficient to enable to consider of angiogenic process in the pathogenesis and lesions progression of oral lichen planus and pemphigus vulgaris, we suggest this process is present in both forms lesion, however, more studies must be made in the near future in order to prepare a well-founded proposal

Expressão imuno-histoquimica da cicloxigenase-2 e p53 em cancinoma epidermóide oral

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

Dupla marcação p53/AgNOR em carcinoma epidermóide oral

The utilization of the immunohistochemical/histochemical double staining technique comes permitting the analysis of two molecular parameters at the same time in an even tissue. Starting from this, the objective of this study was to investigate the existence of differences between the number of NORS/NUCLEUS between p53 positive and p53 negative cells, as well as the existence of correlation between the medium of the NORs of the p53 positive and negative cells and the histological scores of maligninancy in 16 cases of oral squamous cell carcinoma. It was first classified in agreement with the histological grade system of maligninancy proposed by Bryne (1998) and the double staining technique immunohistochemistry/histochemistry was utilized for the achievement to quantify of the NORs in p53 positive and negative cells. It had not significant differences between the medium number of NORs of the p53 positive cells and of the p53 negative cells, and they were not correlated with the histological scores of malignancy. We conclude that the related phenotype to the p53 immunohistochemical expression did not influence the average of NORS/NUCLEUS and this medium, in both positive and negative cells, is not correlated with the degree of histological aggressivity of the oral squamous cell carcinoma