ABSTRACT
El tejido epitelial gastrointestinal normal presenta estructuras glicoesfingolipídicas que son propias de los antígenos ABH, las cuales confieren propiedades biológicas esenciales, dirigen el recambio y el tráfico transcelular y tienen gran importancia para la interacción entre células durante el desarrollo, crecimiento y diferenciación. Está descripto que la glicosilación aberrante es un atributo común del crecimiento neoplásico y uno de los principales determinantes del fenómeno relacionado con el cáncer, como es el crecimiento invasivo de la metástasis. El objetivo de este trabajo fue estudiar la expresión de los antígenos ABH en células epiteliales de neoplasias gastrointestinales. Se trabajó con catorce muestras de tumores gastrointestinales en tacos de parafina aplicando la técnica SRCA (Specific Red Cell Adherence). Se demostró que en 13 de las 14 muestras hubo pérdida total o parcial, o cambio de la expresión antigénica
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Gastrointestinal Neoplasms/diagnosis , Immunohistochemistry/methods , Isoantigens , Biomarkers, Tumor/isolation & purification , Colonic Neoplasms/diagnosis , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/immunology , Glucosyltransferases , Neoplasm Invasiveness/immunology , Genetic Markers/immunology , Biomarkers, Tumor , ABO Blood-Group System/immunology , Stomach Neoplasms/diagnosis , Stomach Neoplasms/immunology , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/immunologyABSTRACT
Gastric cancer and tumor growth regulation. Study of cell proliferation markers and protein complex p53/p21WAF1/CIP1/mdm-2. Background: p53/p21WAF1/CIP1 and mdm-2 proteins play an important role in cell cycle regulation. The study of the pathogenesis of gastric cancer is important to understand how these tumors progress during their natural history. Aim: To study the relationship between the immunohistochemical expression of p53/p21WAF1/CIP1 and mdm-2 and cell proliferation in gastric cancer. Material and methods: Fifty one gastrectomy specimens with gastric cancer were studied using immunohistochemistry for p53/p21WAF1/CIP1 and mdm-2. Cell proliferation was determined by immunolabelling with PCNA and Ki67 antigens. Mitosis figures were counted in 10 high power microscopic fields. Results: Patients from whom gastric cancer specimens were obtained had a mean age of 59.3 years. Ki67 and mitosis counting showed the highest correlation index with proliferation indexes studied. No correlation was found between the expression of protein complex p53/p21WAF1/CIP1 and mdm-2 and morphological characteristics of gastric tumors. Mdm-2 protein overexpression was the only marker that showed an independent correlation with cell proliferation. Moreover, mdm-2 positive tumors showed the highest proliferation indexes when p53 was not immunohistochemically over-expressed, as determined by PCNA labelling index. Conclusions: In gastric cancer, a direct correlation between mdm-2 overexpression and cell proliferation was observed. Moreover, the fact that mdm-2 positive tumors showed the highest cell proliferation when p53 was not overexpressed, entitles us to hypothesize that mdm-2 overexpression could play a major role in gastric carcinogenesis