Syndecan-1 (CD138) and Ki-67 expression in odontogenic cystic lesions

ABSTRACT

The aim of this study was to assess the immunohistochemical expression of syndecan-1 (CD138) and Ki-67 in radicular cysts (RC), dentigerous cysts (DC) and keratocystic odontogenic tumors (KOT). Thirty-five RC, 22 DC and 17 KOT were used in the study and immunohistochemical reactions using anti-syndecan-1 and anti-Ki-67 antibodies were performed by the streptavidin-biotin-peroxidase method. Fisher's exact test and Spearman's correlation coefficient were used for statistical analysis of data. Among the studied lesions, no differences in the syndecan-1 expression were observed, but the suprabasal expression of Ki-67 was significantly higher in KOT (p<0.0001), when compared with RC and DC. In RC, there was positive correlation between the expression (p=0.02) and intensity (p=0.0001) of syndecan-1 and between the intensity of syndecan-1 and Ki-67 expression (p=0.01). In the KOT, Ki-67 expression in the suprabasal layer correlated positively with the expression (p=0.01) and intensity (p=0.01) of syndecan-1. The expression of syndecan-1 does not seem to be a determinant factor of the distinct histopathological features and biological behavior of the studied lesions. Nevertheless, positive correlation between syndecan-1 and a cell proliferation marker was observed in RC and KOT.

RESUMO

O objetivo deste estudo foi avaliar a expressão imunoistoquímica de syndecan-1 (CD138) e Ki-67 em cistos radiculares (CR), cistos dentígeros (CD) e tumores odontogênicos queratocísticos (TOQ). Trinta e cinco CR, 22 CD e 17 TOQ foram utilizados no estudo e as reações imunoistoquímicas usando os anticorpos anti-syndecan-1 e anti-Ki-67 foram realizadas pelo método estreptavidina-biotina-peroxidase. Para análise estatística, o teste exato de Fisher e o coeficiente de correlação de Spearman foram utilizados. Entre as lesões estudadas, não foram observadas diferenças na expressão de syndecan-1, mas a expressão suprabasal de Ki-67 foi significativamente maior nos TOQ (p<0,0001), quando comparado aos CR e CD. No CR, havia correlação positiva entre a expressão (p=0,02) e intensidade (p=0,0001) de syndecan-1 e entre a intensidade de syndecan-1 e expressão de Ki-67 (p=0,01). No TOQ, a expressão de Ki-67 na camada suprabasal correlacionou positivamente com a expressão (p=0,01) e intensidade de expressão (p=0,01) de syndecan-1. A expressão de syndecan-1 não parece ser um fator determinante das características histopatológicas distintas e do comportamento biológico das lesões estudadas. Entretanto, correlação positiva entre syndecan-1 e um marcador de proliferação celular foi evidenciado em CR e TOQ.