Children and adolescents assisted in a referral oral medicine diagnostic service: 20 years of experience in Brazil.

BACKGROUND: Several lesions can affect the oral and maxillofacial region, with trends influenced by lifestyle and age. AIM: To investigate the occurrence of oral and maxillofacial lesions in paediatric patients assisted in an oral medicine diagnostic service in Brazil over 20 years. DESIGN: A retrospective cross-sectional study was performed in an oral medicine diagnostic service (1999-2019). Data included sex, age, anatomic site, and diagnosis from clinical records of children (0-9 years) and adolescents (10-19 years). Lesions were diagnosed through clinical examination. Biopsy and histopathologic examination were performed when necessary. RESULTS: Among 10 530 records, 702 (6.67%) were from patients aged 0-19 years diagnosed with oral or maxillofacial lesions. A high frequency of females was observed (58.1%). Reactive/inflammatory lesions were the most common group of lesions (45.2%), followed by abnormalities of teeth/developmental defects (17.8%) and pulpal and periapical diseases (8.5%). Mucocele/ranula was the most common lesion in children (29.3%) and adolescents (25.3%). Lips were the most affected anatomic sites. CONCLUSION: Most lesions were benign, and mucocele/ranula was the most frequent. Our results did not differ from those of histopathological-based studies, but they provided information on the occurrence of oral and maxillofacial lesions to dentists and paediatricians.

Immunohistochemical expression of beta-catenin, BMP4 and TGF-beta in odontomas.

Changes in the expression of nuclear ß-catenin are responsible for tumorigenesis. Beta-catenin acts synergistically with the TGF-ß/BMPs pathway. This interaction leads to greater dentin deposition and may explain the differences between distinct tooth morphologies and hamartomas. The aim of this study was to investigate the role of ß-catenin, BMP4 and TGF-ß in the development of odontomas. This cross-sectional, retrospective, immunohistochemical study evaluated 30 compound odontomas, 30 complex odontomas and 17 tooth germs. The results showed that BMP4 and TGF-ß were more immunoexpressed in the ectomesenchyme of complex odontomas (median = 33.7, p < 0.001; median = 76.4, p = 0.002, respectively). Higher immunoexpression of BMP4 and TGF-ß was also observed in the epithelium of tooth germs (median = 2.0, p < 0.001; median = 120.3, p < 0.001, respectively). TGF-ß and BMP4 showed a positive and significant correlation (p < 0.001). Both TGF-ß and BMP4 were positively correlated with nuclear ß-catenin in ectomesenchyme (p = 0.047 and p = 0.023, respectively). Developing teeth exhibited higher concentrations of the proteins studied in odontogenic epithelium, especially during the bud and cap stages. Higher immunoexpression in odontomas occurred mainly in the ectomesenchyme. We therefore suggest that changes in the ectomesenchyme can lead to the development of odontomas.

The Anticancer Potential of Kaempferol: A Systematic Review Based on In Vitro Studies.

Given the heterogeneity of different malignant processes, planning cancer treatment is challenging. According to recent studies, natural products are likely to be effective in cancer prevention and treatment. Among bioactive flavonoids found in fruits and vegetables, kaempferol (KMP) is known for its anti-inflammatory, antioxidant, and anticancer properties. This systematic review aims to highlight the potential therapeutic effects of KMP on different types of solid malignant tumors. This review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Searches were performed in EMBASE, Medline/PubMed, Cochrane Collaboration Library, Science Direct, Scopus, and Google Scholar. After the application of study criteria, 64 studies were included. In vitro experiments demonstrated that KMP exerts antitumor effects by controlling tumor cell cycle progression, proliferation, apoptosis, migration, and invasion, as well as by inhibiting angiogenesis. KMP was also able to inhibit important markers that regulate epithelial-mesenchymal transition and enhanced the sensitivity of cancer cells to traditional drugs used in chemotherapy, including cisplatin and 5-fluorouracil. This flavonoid is a promising therapeutic compound and its combination with current anticancer agents, including targeted drugs, may potentially produce more effective and predictable results.

Immunoexpression of HSP27 does not seem to influence the prognosis of oral tongue squamous cell carcinoma.

New methods of early detection and risk assessment have been studied aiming to predict the prognosis of patients and directing a specialized treatment of the oral tongue squamous cell carcinoma (OTSCC). In this context, several molecular biomarkers have been investigated for this purpose, and, among them, the heat shock protein 27 (HSP27) can be named. The study aimed to analyze whether heat shock protein 27 (HSP27) exerts any influence on OTSCC, correlating its immunoexpression with clinicopathological parameters, and patient survival. The sample comprised 55 OTSCC cases and 20 normal oral mucosa specimens. The malignancy grading systems proposed by the WHO in 2005, Brandwein-Gensler et al., and Almangush et al. were applied in a histomorphological study. HSP27 expressions were evaluated through the Immunoreactivity Score System (IRS). Significant values were considered at p <0.05 for all statistical tests. Higher IRS results were observed for normal oral mucosa specimens when compared to OTSCC cases (p <0.001). No significant associations between HSP27 immunostaining, the analyzed clinicopathological parameters and patient survival were observed. The results of the present study indicate lower HSP27 expression in OTSCC cases compared to normal oral mucosa specimens. Thus, HSP27 expression does not seem to influence patient prognosis.

Immunoexpression of HSP27 does not seem to influence the prognosis of oral tongue squamous cell carcinoma

Abstract New methods of early detection and risk assessment have been studied aiming to predict the prognosis of patients and directing a specialized treatment of the oral tongue squamous cell carcinoma (OTSCC). In this context, several molecular biomarkers have been investigated for this purpose, and, among them, the heat shock protein 27 (HSP27) can be named. The study aimed to analyze whether heat shock protein 27 (HSP27) exerts any influence on OTSCC, correlating its immunoexpression with clinicopathological parameters, and patient survival. The sample comprised 55 OTSCC cases and 20 normal oral mucosa specimens. The malignancy grading systems proposed by the WHO in 2005, Brandwein-Gensler et al., and Almangush et al. were applied in a histomorphological study. HSP27 expressions were evaluated through the Immunoreactivity Score System (IRS). Significant values were considered at p <0.05 for all statistical tests. Higher IRS results were observed for normal oral mucosa specimens when compared to OTSCC cases (p <0.001). No significant associations between HSP27 immunostaining, the analyzed clinicopathological parameters and patient survival were observed. The results of the present study indicate lower HSP27 expression in OTSCC cases compared to normal oral mucosa specimens. Thus, HSP27 expression does not seem to influence patient prognosis.

Resumo Novos métodos de detecção precoce e avaliação de risco estão sendo estudados com o intuito de predizer o prognóstico dos pacientes e direcionar um tratamento diferenciado. Neste contexto, vários biomarcadores moleculares têm sido investigados com esta finalidade, dentre eles a heat shock protein 27 (HSP27). Esta pesquisa objetivou analisar se a HSP27 exerce alguma influência nos carcinomas de células escamosas de língua oral (CCELO), correlacionando a sua imunoexpressão com parâmetros clinicopatológicos e com a sobrevida dos pacientes. A amostra foi constituída por 55 casos de CCELO e 20 espécimes de mucosa oral normal. Os sistemas de gradação de malignidade propostos pela OMS em 2005, Brandwein-Gensler et al. e Almangush et al. foram aplicados em um estudo histomorfológico. A expressão da HSP27 foi avaliada através do Sistema de Escore de Imunorreatividade (IRS). Para todos os testes estatísticos foram considerados valores significativos com p<0,05. Foi observado um maior IRS para a mucosa oral normal quando comparado aos casos de CCELO (p<0,001). Não foram encontradas associações significativas entre a imunomarcação da HSP27 com os parâmetros clinicopatológicos analisados e com a sobrevida dos pacientes. Os resultados do presente estudo indicam uma menor expressão da HSP27 nos casos de CCELO quando comparados aos espécimes de mucosa oral normal. Assim, a expressão da HSP27 parece não influenciar o prognóstico dos pacientes.

EGFR, VEGF, and angiogenesis promote the development of lipoma in the oral cavity.

This study aimed to detect, quantify and compare the immunohistochemical expression of EGFR and VEGF and microvessel count (MVC) in oral lipomas, and to correlate the findings with clinical and morphological characteristics of the cases studied. The sample consisted of 54 oral lipomas (33 classic and 21 non-classic) and 23 normal adipose tissue specimens. Cytoplasmic and/or nuclear immunohistochemical staining of EGFR and VEGF was analyzed. The angiogenic index was determined by MVC. Cells were counted using the Image J® software. The Statistical Package for the Social Sciences was used for data analysis, adopting a level of significance of 5% for all statistical tests. A statistically significant difference in EGFR immunoexpression (p=0.047), especially, between classic lipomas and normal adipose tissue. There was a significant difference in MVC between non-classic lipomas and normal adipose tissue (p=0.022). In non-classic lipomas, only VEGF immunoexpression showed a significant moderate positive correlation (r=0.607, p=0.01) with MVC. In classic lipomas, the number of EGFR-immunostained adipocytes was directly proportional to the number of VEGF-positive cells, demonstrating a significant moderate positive correlation (r=0.566, p=0.005). The results suggest that EGFR, VEGF, and angiogenesis participate in the development of oral lipomas but are not primarily involved in the growth of these tumors.

SNAIL1 is involved in the control of the epithelial-mesenchymal transition in oral tongue squamous cell carcinoma.

OBJECTIVE: The aim of the present study was to investigate the role of SNAIL1, E-cadherin, and N-cadherin immunoexpression in oral tongue carcinogenesis. In addition, we evaluated in vitro the impact of silencing of the nuclear transcription factor SNAIL1 on the viability, apoptosis, proliferation, migration, and invasion of SCC-9 and HSC-3 cells. STUDY DESIGN: Immunohistochemical analysis of SNAIL1, E-cadherin, and N-cadherin was carried out in 47 samples representing oral epithelial dysplasia (OED) and 41 oral tongue squamous cell carcinoma (OTSCC). The suppression of SNAIL1 expression was performed using shRNA-expression vectors in HSC-3 and SCC-9 cells to investigate in vitro the impact of SNAIL1 on proliferation, apoptosis, viability, migration, and invasion of SCC-9 and HSC-3 cells. RESULTS: Significant differences were observed in the expression of SNAIL1, E-cadherin, and N-Cadherin between OTSCC and OED. A low membrane expression of E-cadherin was strongly associated with poor overall survival in patients with OTSCC (P < .05), but the association did not withstand the Cox multivariate survival analysis. SNAIL1 silencing played a key role in the suppression of epithelial-mesenchymal transition and inhibited migration and invasion of HSC-3 cells (P < .0001, P < .01, respectively). In SCC-9 cells, SNAIL1 silencing promoted a significant reduction in the proliferation (P < .0001) and invasion (P < .0001). CONCLUSIONS: The epithelial-mesenchymal transition is present in different stages of oral tongue carcinogenesis, and SNAIL1 plays a key role in this process, although the underlying mechanisms still need to be elucidated. Thus, SNAIL1 might be a promising therapeutic target in OTSCC.

EGFR, VEGF, and angiogenesis promote the development of lipoma in the oral cavity

Abstract This study aimed to detect, quantify and compare the immunohistochemical expression of EGFR and VEGF and microvessel count (MVC) in oral lipomas, and to correlate the findings with clinical and morphological characteristics of the cases studied. The sample consisted of 54 oral lipomas (33 classic and 21 non-classic) and 23 normal adipose tissue specimens. Cytoplasmic and/or nuclear immunohistochemical staining of EGFR and VEGF was analyzed. The angiogenic index was determined by MVC. Cells were counted using the Image J® software. The Statistical Package for the Social Sciences was used for data analysis, adopting a level of significance of 5% for all statistical tests. A statistically significant difference in EGFR immunoexpression (p=0.047), especially, between classic lipomas and normal adipose tissue. There was a significant difference in MVC between non-classic lipomas and normal adipose tissue (p=0.022). In non-classic lipomas, only VEGF immunoexpression showed a significant moderate positive correlation (r=0.607, p=0.01) with MVC. In classic lipomas, the number of EGFR-immunostained adipocytes was directly proportional to the number of VEGF-positive cells, demonstrating a significant moderate positive correlation (r=0.566, p=0.005). The results suggest that EGFR, VEGF, and angiogenesis participate in the development of oral lipomas but are not primarily involved in the growth of these tumors.

Resumo Lipomas são as neoplasias mesenquimais benignas mais comuns, no entanto sua etiopatogenia ainda permanece desconhecida. Dessa forma, essa pesquisa teve como objetivo detectar, quantificar e comparar a expressão imunoistoquímica do EGFR, VEGF e contagem microvascular (MVC) dos lipomas orais, relacionando-os com as características clínicas e morfológicas dos casos estudados. A amostra foi composta por 54 lipomas orais (33 clássicos e 21 não clássicos) e 23 casos de tecido adiposo normal. A análise da expressão imunoistoquímica de EGFR e VEGF foi fundamentada na marcação citoplasmática e/ou nuclear. O índice angiogênico foi avaliado por meio da MVC. A contagem de células foi realizada utilizando software IMAGE J®. Os dados obtidos foram analisados no software Statistical Package for Social Science. O nível se significância de 5% foi adotado para os testes estatístico. A análise da imunoexpressão das proteínas revelou para o EGFR diferença estatisticamente significativa (p=0,041) entre o lipoma clássico e o tecido adiposo normal. Houve diferença significativa na MVC entre lipomas não clássicos e tecido adiposo normal (p=0,022). Nos lipomas não clássicos, apenas a imunoexpressão de VEGF apresentou correlação do tipo moderada, positiva e significativa (r=0,607; p=0,010) em relação a MVC. Ademais, nos lipomas clássicos foi percebido que os adipócitos imunomarcados para EGFR estiveram diretamente proporcionais a imunoexpressão de VEGF, apresentando correlação do tipo moderada, positiva e estatisticamente significativa (r=0,566; p = 0,005). Com base nos resultados, pode-se sugerir que o EGFR, VEGFR e MCV participam do desenvolvimento nos lipomas orais, contudo, não estão primariamente envolvidos no crescimento tumoral dessas neoplasias.

A 14-year retrospective study focusing on clinical and morphological features of oral cavity lipomas: A review of main topics.

BACKGROUND: Lipomas are benign soft tissue neoplasms frequently found in the human body. Head and neck lipomas are relatively uncommon, accounting for 1 to 4% of benign lesions at this location. This 14-year retrospective study analyzed the clinical-pathological features of cases of oral cavity lipomas and their histopathological variants seen at a single oral pathology referral center. MATERIAL AND METHODS: Data on age, sex, anatomical location, clinical diagnosis, and histological subtypes were collected from all cases microscopically diagnosed as lipoma. Three previously trained oral pathologists re-evaluated hematoxylin/eosin-stained slides of all selected cases. RESULTS: Among 7,861 oral and maxillofacial lesions diagnosed at the service, 95 (1.2%) were lipomas or their histopathological variants. There was a predominance of female patients (n = 65; 68%); the mean age at diagnosis was 58.8 years (±13.56). We found the following histological subtypes: conventional lipoma, fibrolipoma, spindle cell lipoma, sialolipoma, osteolipoma, chondrolipoma, and intramuscular lipoma. The buccal mucosa was the most affected site. Conventional lipoma and fibrolipoma were the most commonly diagnosed histological variants. Although most lipomas are asymptomatic, large lipomas can occur, reaching a diameter of 4 cm. CONCLUSION: The present study reinforces the importance of careful clinical and histopathological examination in order to obtain an accurate diagnosis and to ensure appropriate treatment.

Differential protein expression of osteoclastogenic factors in odontogenic cysts and tumors.

The osteolytic activity of odontogenic cysts and tumors is directly associated with their growth and aggressiveness. The influence of proteins expressed by epithelial and mesenchymal cells on this biological event differs between indolent cystic lesions, aggressive cystic lesions, and odontogenic tumors. The objective of this study was to compare the immunohistochemical expression of factors that stimulate (receptor activator of nuclear factor kappa-Β ligand - RANKL, cathepsin K - CatK and matrix metallopeptidase 8 - MMP-8) and inhibit (osteoprotegerin - OPG) osteoclastogenesis between dentigerous cyst (DC), glandular odontogenic cyst (GOC), odontogenic keratocyst (OKC), and ameloblastoma (AB). Paraffin-embedded sections of nine DCs, nine GOCs, 20 OKCs, 21 ABs, and four dental follicles (DFs) were subjected to immunohistochemistry. Immunoreactivity was analyzed semiquantitatively and quantitatively in epithelium and connective tissue, respectively. The proteins were immunoexpressed in epithelial and mesenchymal cells of all lesions studied. The expression of RANKL and CatK was higher in OKC, AB, and GOC (p<0.005). Higher expression of OPG was found in DF and DC compared to the other markers (p<0.005). MMP-8 expression was high in GOC and OKC. This study demonstrated the differential expression of factors that inhibit and stimulate bone resorption during the development of DC, GOC, OKC, and AB. Higher expression of RANKL and CatK was observed in more aggressive lesions. OPG appears to be one of the molecules responsible for the slower growth of DC.

Biological marker for the establishment of periodontal disease: cross-sectional study in the gingival tissue.

BACKGROUND: The present study investigated the expression of COX-2, EMMPRIN, HIF-1α, and GLUT-1 in the gingival tissue to verify if there is a correlation between the immunoexpression of these proteins and the changes caused by the inflamed infiltrate present in the gingival tissues. MATERIAL AND METHODS: A morphological analysis of epithelial changes (hyperplasia, exocytosis, spongiosis, and hydropic degeneration) was performed, as well as a semiquantitative analysis of the immunoexpression of COX-2, EMMPRIN, HIF-1α, and GLUT-1 in the epithelium and connective tissue of 60 specimens of gingival tissue. RESULTS: Epithelial immunoexpression to COX-2 was observed in three cases, while EMMPRIN, HIF-1α, and GLUT-1 were strongly expressed in the basal layer of the epithelium and gradually decreased until the upper layers. In the connective tissue, COX-2 immunoexpression showed a statistically significant association (p < 0.001) with the gingival inflammatory infiltrate. In connective tissue, EMMPRIN and HIF-1α exhibited intense immunopositivity, while GLUT-1 was negative in most cases. CONCLUSION: COX-2 expression may constitute a biological marker of gingival tissues since its epithelial immunoexpression may indicate a greater propensity for the establishment of periodontal disease.

Immunohistochemical analysis of SHH, SMO and GLI-1 proteins in epithelial odontogenic lesions.

The present study analyzed the expression of proteins involved in the sonic hedgehog signaling pathway (SHH, SMO, and GLI-1) in benign epithelial odontogenic lesions (odontogenic keratocyst - OKC, ameloblastoma - AB, and adenomatoid odontogenic tumor - AOT) in order to identify the role of these proteins in the pathogenesis of these lesions. The sample consisted of 20 OKCs, 20 ABs, and 10 AOTs. The Kruskal-Wallis, Mann-Whitney U, and Spearman's (r) tests were used for statistical analysis, with the level of significance set at 5% (p < 0.05). The membrane/cytoplasmic expression of SHH was significantly higher in AB compared to AOT (p = 0.022) and OKC (p = 0.02). No differences were found in the membrane/cytoplasmic expression of SMO between the lesions studied. Regarding GLI-1, significant differences were observed at the nuclear level for AB and OKC compared to AOT (p < 0.0001). In addition, significant positive correlations were found between cytoplasmic and nuclear GLI-1 in AB (r = 0.482; p = 0.031) and OKC (r = 0.865; p < 0.0001), and between membrane/cytoplasmic SMO and cytoplasmic GLI-1 in AOT (r = 0.667; p = 0.035) and OKC (r = 0.535; p = 0.015). The results of this study confirm the participation of the sonic hedgehog signaling pathway in the pathogenesis of the lesions studied. Overexpression of SHH in ABs and nuclear expression of GLI-1 in ABs and OKCs indicate that these proteins contribute to the more aggressive behavior of these two lesions when compared to AOT.

Immunohistochemical analysis of SHH, SMO and GLI-1 proteins in epithelial odontogenic lesions

Abstract The present study analyzed the expression of proteins involved in the sonic hedgehog signaling pathway (SHH, SMO, and GLI-1) in benign epithelial odontogenic lesions (odontogenic keratocyst - OKC, ameloblastoma - AB, and adenomatoid odontogenic tumor - AOT) in order to identify the role of these proteins in the pathogenesis of these lesions. The sample consisted of 20 OKCs, 20 ABs, and 10 AOTs. The Kruskal-Wallis, Mann-Whitney U, and Spearman's (r) tests were used for statistical analysis, with the level of significance set at 5% (p < 0.05). The membrane/cytoplasmic expression of SHH was significantly higher in AB compared to AOT (p = 0.022) and OKC (p = 0.02). No differences were found in the membrane/cytoplasmic expression of SMO between the lesions studied. Regarding GLI-1, significant differences were observed at the nuclear level for AB and OKC compared to AOT (p < 0.0001). In addition, significant positive correlations were found between cytoplasmic and nuclear GLI-1 in AB (r = 0.482; p = 0.031) and OKC (r = 0.865; p < 0.0001), and between membrane/cytoplasmic SMO and cytoplasmic GLI-1 in AOT (r = 0.667; p = 0.035) and OKC (r = 0.535; p = 0.015). The results of this study confirm the participation of the sonic hedgehog signaling pathway in the pathogenesis of the lesions studied. Overexpression of SHH in ABs and nuclear expression of GLI-1 in ABs and OKCs indicate that these proteins contribute to the more aggressive behavior of these two lesions when compared to AOT.

Resumo O presente estudo analisou a expressão de proteínas envolvidas na via de sinalização Sonic Hedgehog (SHH, SMO e GLI-1) em lesões benignas do epitélio odontogênico de comportamento biológico distintos, tais como ceratocistos odontogênicos (CO), ameloblastomas (AMB) e tumores odontogênicos adenomatoides (TOA), com o intuito de identificar o papel destas proteínas na patogênese destas lesões. A amostra foi constituída de 20 CO, 20 AMB e 10 TOA, analisada pela técnica da imuno-histoquímica de forma semiquantitativa por compartimento celular, onde foi feita uma análise da membrana e citoplasma das células nas proteínas SHH e SMO, enquanto que para a proteína GLI-1, foi feita uma análise nuclear e/ou citoplasmática. Para análise estatística, foram utilizados os testes de Kruskal-Wallis (KW), Mann-Whitney (U) e Spearman (r), com o nível de significância estabelecido em 5% (p < 0,05). Ao analisar a proteína SHH, observou-se que o AMB demonstrou expressão membranar/citoplasmática significativamente maior em comparação ao TOA (p = 0,022) e CO (p = 0,020). Com relação à análise membranar/citoplasmática da SMO, não foram identificadas diferenças entre as lesões estudadas. Para a proteína GLI-1, foram constatadas diferenças estatisticamente significativas, em nível nuclear, para o AMB e CO em comparação ao TOA (p< 0,0001). Além disso, foram observadas correlações positivas com significância estatística entre GLI-1 citoplasmático e GLI-1 nuclear para o AMB (r = 0,482; p = 0,031) e CO (r = 0,865; p< 0,0001), e entre o SMO membranar/citoplasmático e o GLI-1 citoplasmático para o TOA (r = 0,667; p = 0,035) e o CO (r = 0,535; p = 0,015). Os resultados deste estudo confirmam a participação da via de sinalização Sonic Hedgehog na patogênese das lesões estudadas e, a superexpressão de SHH em AMBs e GLI-1 nuclear em AMBs e COs, indica que estas proteínas contribuem com o comportamento biológico mais agressivo destas duas lesões quando comparado ao TOA.

DNA damage through oxidative stress is an important event in oral leukoplakia.

OBJECTIVE: To evaluate the oxidative DNA damage, through 8-hydroxy-2'-deoxyguanosine (8-OHdG), and its repair by base excision repair pathway [Redox factor-1 (Ref-1); X-ray Repair Cross Complementing-1 (XRCC-1)] in different epithelial dysplasia degrees in oral leukoplakia. DESIGN: Forty-four cases of oral leukoplakia and 10 normal oral mucosa were quantified for 8-OHdG, Ref-1, and XRCC-1 through immunohistochemistry. RESULTS: Cytoplasmic 8-OHdG and nuclear XRCC-1 were significantly associated with multiple synchronous lesions (p = 0.048; p = 0.034, respectively). Nuclear Ref-1 was significantly associated with oral leukoplakia on the tongue (p = 0.027). A significantly gradual cytoplasmic 8-OHdG expression increase was observed between normal oral mucosa and epithelial dysplasia (p < 0.05). Nuclear Ref-1 expression was significantly lower (p < 0.01) in non-dysplasia/mild dysplasia, while its cytoplasmic expression was significantly higher in non-dysplasia/mild dysplasia compared to moderate/severe dysplasia and normal oral mucosa (p = 0.03; p < 0.0001, respectively). A significantly higher cytoplasmic XRCC-1 expression was observed in non-dysplasia/mild and moderate/severe dysplasia compared to normal oral mucosa (p < 0.0001; p < 0.0001, respectively). All epithelial dysplasia degrees showed a correlation between nuclear and cytoplasmic expression of these proteins (p < 0.05). CONCLUSIONS: 8-OHdG formation may not play a role in the development of multiple synchronous oral leukoplakias. However, it is related to the severity of the epithelial dysplasia. The subcellular level of Ref-1 implies different roles according to the degree of epithelial dysplasia. Cytoplasmic XRCC-1 expression indicates a possible failure of the DNA repair mechanism and occurs in early morphological stages of epithelial dysplasia.

Differential protein expression of osteoclastogenic factors in odontogenic cysts and tumors

Abstract: The osteolytic activity of odontogenic cysts and tumors is directly associated with their growth and aggressiveness. The influence of proteins expressed by epithelial and mesenchymal cells on this biological event differs between indolent cystic lesions, aggressive cystic lesions, and odontogenic tumors. The objective of this study was to compare the immunohistochemical expression of factors that stimulate (receptor activator of nuclear factor kappa-Β ligand - RANKL, cathepsin K - CatK and matrix metallopeptidase 8 - MMP-8) and inhibit (osteoprotegerin - OPG) osteoclastogenesis between dentigerous cyst (DC), glandular odontogenic cyst (GOC), odontogenic keratocyst (OKC), and ameloblastoma (AB). Paraffin-embedded sections of nine DCs, nine GOCs, 20 OKCs, 21 ABs, and four dental follicles (DFs) were subjected to immunohistochemistry. Immunoreactivity was analyzed semiquantitatively and quantitatively in epithelium and connective tissue, respectively. The proteins were immunoexpressed in epithelial and mesenchymal cells of all lesions studied. The expression of RANKL and CatK was higher in OKC, AB, and GOC (p<0.005). Higher expression of OPG was found in DF and DC compared to the other markers (p<0.005). MMP-8 expression was high in GOC and OKC. This study demonstrated the differential expression of factors that inhibit and stimulate bone resorption during the development of DC, GOC, OKC, and AB. Higher expression of RANKL and CatK was observed in more aggressive lesions. OPG appears to be one of the molecules responsible for the slower growth of DC.

Involvement of tryptase-positive mast cells and angiogenesis in the growth of inflammatory odontogenic cysts.

Inflammatory periapical lesions are characterized by infiltration of different immune cell types, the functions of which depend on an effective vascular network. This study aimed to evaluate the mast cells density (MCD) in inflamatory odontogenic cysts capsules concerning microvascular density (MVD), microvascular area (MVA), and microvascular perimeter (MVP), and correlate such findings with the type of lesion, intensity of the inflammatory infiltrate, and thickness of the epithelial lining. Twenty inflamatory dentigerous cysts (IDCs), twenty radicular cysts (RCs), and twenty residual radicular cysts (RRCs) were submitted to immunohistochemical analysis using anti-tryptase and anti-CD34 antibodies. RCs exhibited the highest MCD, MVD, MVA, and MVP indexes (p = < 0.001, p = 0.008, p = 0.003 and p = < 0.001, respectively), and lesions with inflammatory infiltrate grade III showed the highest MVD (p = 0.044). Considering epithelial thickness, a higher MVP index was identified in lesions with hyperplastic epithelium (p = 0.018). In IDCs, RCs, and RRCs, a strong positive correlation was observed between MVA and MVP (r = 0.950 and p = < 0.001; r = 0.914 and p = < 0.001; r = 0.713 and p = < 0.001, respectively). In IDCs, a moderate correlation was observed between MCD and both MVA and MVP (r = 0.660 and p = 0.002; r = 0.634 and p = 0.003, respectively). These results suggest that tryptase-positive mast cells might play an important role in the angiogenic activity of IDCs, while RCs had the highest indexes. Our findings also confirmed that the intensity of the inflammatory infiltrate and epithelial thickness influence angiogenesis.

Identification of elastofibroma and elastofibroma-like lesions in cases diagnosed as oral fibromas.

We investigated elastofibromas (EF) and elastofibroma-like structures (EFL) in 95 cases that had been diagnosed as oral fibromas (OF). Histological sections were stained with Verhoeff-Van Gieson, Congo red and hematoxylin and eosin to enable possible reclassification to EF or EFL, or to retain the diagnosis of OF. To do this, we identified amyloid and used histopathological descriptions and epidemiological clinical profiles. We found 56 EF and 21 EFL cases, while 18 diagnoses of OF were retained. We observed a predilection for EF in females. Also, the most common site for OF was the cheek mucosa. We also found a longer time course for lesion development for OF compared to the other lesions. We found a relation between elastic fibers and amyloid material in EF. We also observed perivascular fibrotic lesions (PVFL) in EF. Most cases of EF exhibited more elastic fibers, thicker fibers, stronger relation with amyloid material deposition, rare evidence of PVFL and a longer time course for development compared to the other lesions. We suggest that EFL may give rise to oral EF.

DNA base excision repair and nucleotide excision repair proteins in malignant salivary gland tumors.

OBJECTIVE: To analyze the immunohistochemical expression of the base excision repair (BER) proteins apurinic/apyrimidinic endonuclease 1 (APE1) and X-ray repair cross-complementing protein 1 (XRCC1) and nucleotide excision repair (NER) protein xeroderma pigmentosum group F (XPF) in malignant salivary gland tumors (MSGTs). DESIGN: Sixty-two cases of MSGTs were selected, including 14 acinic cell carcinomas (AcCC), 15 polymorphous adenocarcinomas (PAC), 16 adenoid cystic carcinomas (ACC), and 17 mucoepidermoid carcinomas (MEC). The specimens were submitted to quantitative immunohistochemical analysis. RESULTS: All MSGTs exhibited nuclear or nucleo-cytoplasmic immunostaining of APE1, XRCC1 and XPF, with a high percentage of positive cells (median = 78.31, 70.48 and 75.46, respectively). XRCC1 expression was higher in PAC compared to MEC (p = 0.032). Nuclear APE1 immunostaining was significantly higher than nucleo-cytoplasmic expression in the selected MSGTs (p < 0.0001). APE1 expression was significantly associated with T1-T2 tumors in ACC (p = 0.006). Increased expression of XPF was associated with age older than 60 years in MEC (p = 0.015) and with ACC involving the minor salivary gland (p = 0.012), while a lower expression was found in AcCC and ACC patients treated by surgery combined with adjuvant therapy (p = 0.036 and p = 0.020, respectively). Low expression of XRCC1 in the nucleus (p = 0.028) and concomitant expression of this protein in the nucleus/cytoplasm were associated with a lower overall 5-year survival rate (p = 0.017). CONCLUSIONS: This study showed that BER and NER proteins evaluated are highly expressed in the MSGTs studied, indicating mechanisms of genotoxic control in these tumors. In addition, the dysregulation of XRCC1 expression was a prognostic predictor in MSGTs analyzed.

Involvement of tryptase-positive mast cells and angiogenesis in the growth of inflammatory odontogenic cysts

Abstract: Inflammatory periapical lesions are characterized by infiltration of different immune cell types, the functions of which depend on an effective vascular network. This study aimed to evaluate the mast cells density (MCD) in inflamatory odontogenic cysts capsules concerning microvascular density (MVD), microvascular area (MVA), and microvascular perimeter (MVP), and correlate such findings with the type of lesion, intensity of the inflammatory infiltrate, and thickness of the epithelial lining. Twenty inflamatory dentigerous cysts (IDCs), twenty radicular cysts (RCs), and twenty residual radicular cysts (RRCs) were submitted to immunohistochemical analysis using anti-tryptase and anti-CD34 antibodies. RCs exhibited the highest MCD, MVD, MVA, and MVP indexes (p = < 0.001, p = 0.008, p = 0.003 and p = < 0.001, respectively), and lesions with inflammatory infiltrate grade III showed the highest MVD (p = 0.044). Considering epithelial thickness, a higher MVP index was identified in lesions with hyperplastic epithelium (p = 0.018). In IDCs, RCs, and RRCs, a strong positive correlation was observed between MVA and MVP (r = 0.950 and p = < 0.001; r = 0.914 and p = < 0.001; r = 0.713 and p = < 0.001, respectively). In IDCs, a moderate correlation was observed between MCD and both MVA and MVP (r = 0.660 and p = 0.002; r = 0.634 and p = 0.003, respectively). These results suggest that tryptase-positive mast cells might play an important role in the angiogenic activity of IDCs, while RCs had the highest indexes. Our findings also confirmed that the intensity of the inflammatory infiltrate and epithelial thickness influence angiogenesis.

Polymorphisms of matrix metalloproteinase-7 and -9 are associated with oral tongue squamous cell carcinoma

Abstract Matrix degradation is an important event in the progression, invasion and metastasis of malignant head and neck lesions. Imbalances, mutations and polymorphisms of MMPs and their inhibitors are observed in several cancer subtypes. The aim of this study was to evaluate the association of the MMP-7 gene promoter (181 A/G) and MMP-9 (-1562 C/T) polymorphisms in oral tongue squamous cell carcinoma (OTSCC). MMP-7 (rs11568818) and MMP-9 (rs3918242) single-nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 71 cases of OTSCC. Normal tissue specimens were obtained from 60 healthy volunteers to serve as the control. The MMP-7 G allele and MMP-9 T allele were more frequent in the OTSCC group than the control group, but only when these two SNPs were taken together was a significant association found with the nodal metastasis of OTSCC (p < 0.001). Based on our results, SNPs in the promoter region of MMP-7 and MMP-9 appear to be associated with greater risk of developing OTSCC, and with a higher propensity to form metastatic tumors. In this respect, molecular studies investigating polymorphisms may be useful in predicting tumor behavior.