Revista de Odontologia da UNESP
Revista de Odontologia da UNESP
Original Article

Imunoexpressão da proteína hMSH2 em leucoplasia bucal

Imunodetection of protein hMSH2 in the oral leukoplakia

Pontes, F.S.C.; Pontes, H.A.R.; Aguiar, M.C.F.; Silveira Jr., J.B.; Silva, T.S.P.; Mesquita, R.A.

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A leucoplasia é a principal alteração potencialmente maligna da boca. Embora o fumo, intensificado pelo consumo de álcool, seja o agente etiológico mais importante para a leucoplasia bucal, estudos complementares são importantes para o entendimento da patogenia da transformação maligna dessa alteração. Realizou-se este estudo com o objetivo de analisar a imunoexpressão da proteína de reparo do DNA hMSH2 em amostras de leucoplasia bucal com aspectos morfo-citológicos de hiperceratose e atipia epitelial (discreta, moderada e acentuada), assim como no epitélio de mucosa bucal normal. Os resultados não mostraram diferenças estatisticamente significantes quando as imunomarcações das graduações histológicas das leucoplasias bucais foram avaliadas entre si, assim como não houve diferenças estatisticamente significantes com a mucosa bucal normal. Esses resultados avaliados em conjunto sugerem que a proteína hMSH2 não está relacionada aos variados graus de atipia epitelial encontrados na histopatologia da leucoplasia bucal, sugerindo que a proteína hMSH2 não participa do processo de transformação maligna da leucoplasia bucal para carcinoma epidermóide. Porém, mais estudos são necessários para confirmar esses resultados.


Carcinogênese, imuno-histoquímica, leucoplasia bucal, hMSH2


The oral leukoplakia is the main oral precancerous lesion. Even though the fume, potentiated by alcohol drinks, is the most important etiologic agent of both oral leukoplakia and squamous cells carcinoma, other complementary studies are necessary for the pathogenesis understanding of the malignant transformation of this lesion. Therefore, the purpose of this study was to describe and to analyze the repair protein of DNA hMSH2 protein immunoexpression in oral leukoplakia samples with different degrees of epithelial dysplasia (mild, moderated and severe), as well as in normal oral mucosa epithelium. The results did not show significant statistic differences when the oral leukoplakia with different degrees of epithelial dysplasia were compared with each other, neither there was a statistical significant difference among the oral leukoplakia samples and the normal oral mucosa. These results suggest that the hMSH2 protein does not partake on oral leukoplakia development into oral squamous cells carcinoma.


Carcinogenesis, immunohistochemical, oral leucoplakia


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