Relación histopatológica de la displasia epitelial con la oncoproteína p53 en la leucoplasia bucal / Histopathological relation of epithelial dysplasia to p53 oncoprotein in oral leukoplakia

La leucoplasia bucal es una lesión precancerosa bien conocida debido a su asociación con la presencia de displasia epitelial y su tendencia a la transformación maligna. Con el fin de eliminar la subjetividad en la determinación de los grados de la displasia epitelial se han utilizado marcadores biológicos, entre ellos, el AcM anti p53. Por ello se propuso evaluar la expresión del AcM anti p53 en los diferentes grados de displasia epitelial en la leucoplasia bucal. Se emplearon las biopsias de 46 pacientes con diagnóstico de leucoplasia bucal, procedentes del Departamento de Patología Bucal de la Facultad de Estomatología de La Habana. Las muestras fueron procesadas por la técnica de inclusión en parafina y coloreadas con la técnica inmunohistoquímica del complejo avidina-biotina-peroxidasa para el AcM p53. Se estudió la correlación entre el patrón de inmunoensayo para p53 y el grado de displasia epitelial. Se evidenció que existe una asociación significativa entre la inmunocoloración de las células basales y suprabasales del epitelio con la oncoproteína p53, en los distintos grados de severidad de la displasia epitelial, lo que pudiera estar relacionado con el incremento progresivo de atipia celular observada. Se concluyó que en las muestras estudiadas existió una relación coincidente del aumento del grado de severidad de la displasia epitelial, con el marcaje de la oncoproteína p53. Estas evidencias sugirieron que el análisis inmunohistoquímico de p53 en conjunto con los parámetros histológicos, principalmente relacionados con el grado de severidad de la displasia epitelial, pudiera ser utilizado para lograr un diagnóstico más certero y contribuir a la prevención del cáncer bucal(AU)

The oral leukoplasia is a well known precancerous injury due to its association with the presence of epithelial dysplasia and its trend to malignant transformation. To eliminate the subjectivity in the determination of the epithelial dysplasia degrees, biological markers have been used among them the AcM.antip53 Thus, authors assessed the expression of AcM antip53 in the different degrees of epithelial dysplasia in the oral leukoplasia. Biopsies from 46 patients diagnosed with oral leukoplasia were used from the Oral Pathology Department of the Stomatology Faculty of La Habana. Samples were processed by the paraffin-inclusion technique and stained with immunohistochemical technique of the avidin-biotin-peroxidase complex for the AcM p53. The correlation between the immunoassay pattern for p53 and the degree of epithelial dysplasia was studied. It was demonstrated that there is a significant association between the immunostain of basal and supra-basal cells of epithelium with the p53 oncoprotein in the different degrees of severity of the epithelial dysplasia, which could be related to the progressive increase of the observed cellular atypia. We concluded that in the study samples there was a coincident relation of the increase in the degree of severity of the epithelial dysplasia, with the marking of the p53 oncoprotein. These evidences suggested that the immunohistochemical analysis of p53 overall with the histological parameters mainly those related to the degree of severity of the epithelial dysplasia could be used to made a more accurate diagnosis and to contribute to prevention of oral cancer(AU)

Iodine staining and P53 oncoprotein for the diagnosis of early esophageal cancer and precancerous lesion / 中华消化内镜杂志

Objective To explore the feasibility of Lugol's iodine staining in association with P53 oncoprotein test to detect early esophageal cancer and precancerous lesions through endoscopy. Methods Lugol's iodine was sprayed on esophageal mucosa under endoscopy in 78 patients with suspected early malignancy. Severe dysplasia which taken from unstained position by iodine were prepared immunohistochemically for P53 oncoprotein study. Then endoscopic mucosal resection (EMR) was performed to these severe dysplasia with P53 oncoprotein－ positive mucosa. Results There were 31 unstained areas (25 patients) including squamous cell carcinomas (n=3) and severe dysplasias (n=16). Expression of P53 was found in 7 severe dysplasia (43.8％ ),and 1 carcinoma in situ was found by EMR. Conclusion This modified method seemed feasible not only to detect early esophageal cancer,but also to resect severe dysplasia mucosa selectively by EMR.

Polymerase Chain Reaction Analysis of Human Papillomavirus in Esophageal Squamous Cell Carcinoma with its Correlation to p53 mutation

HPV infection has been implicated strongly in the pathogenesis of human squamous cell carcinoma(SCC). We analysed a series of 28 surgically removed, invasive squamous cell carcinoma of the esophagus by polymerase chain reaction to detect HPV DNA using consensus primers and 8 type-specific primers of HPV (6, 11, 16, 18, 31, 33, 35, 51). HPV 6, 31, 35 or 51 DNA were detected in 20 out of 28 cases (71.4%) of the esophageal SCCs. HPV 51 was the most frequently detected type, occuring in 13 out of 28 cases (46.4%). p53 immunohistochemical staining was also performed to demonstrate any relationship to HPV DNA positivity. It showed positivity in 16 out of 28(57.1%) esophageal SCCs, and HPV DNA and p53 positivity were concurrently detected in 11 out of 28 cases of SCCs. There was no significant inverse relation between HPV DNA positivity and p53 expression(p>0.05). Our results supported HPV involvement in esophageal squamous cell carcinoma, and suggested there may be another pathway not related to the p53-binding pathway in the carcinogenesis of esophageal SCCs by HPV.