ABSTRACT
ABSTRACT BACKGROUND: There are cases of colorectal tumors that, although small, show more aggressive evolution than large tumors. This motivated us to study whether there are any proteins capable of alerting about these changes. The aim here was to correlate the immunoexpression of the TS, p53, COX2, EGFR, MSH6 and MLH1 biomarkers in tumors in patients with colorectal adenocarcinoma, with the degree of cell differentiation, tumor staging and clinical-pathological prognostic factors. DESIGN AND SETTING: Retrospective observational study at a public tertiary-level hospital. METHODS: We analyzed tissue-microarray paraffin blocks of tumor tissues that had been resected from 107 patients. We used Fisher's exact test to study associations between tumor differentiation/staging and the immunoexpression of biomarkers. We also used Kaplan-Meier estimation, the log-rank test and the adjusted Cox regression model to investigate the patients' overall survival (in months) according to biomarkers and disease-free interval. RESULTS: The degree of tumor differentiation and tumor staging were not associated with the biomarkers, except in cases of patients in stages III or IV, in which there was a correlation with MLH1 expression (P=0.021). Patient survival and disease-free interval were not associated with the biomarkers. CONCLUSION: There were no associations between the degree of tumor differentiation, staging, length of survival or disease-free interval and the immunoexpression of the TS, p53, COX2, EGFR or MSH6 tumor markers. In advanced cases of colorectal adenocarcinoma (stages III and IV), there was a higher percentage of MLH1-negative results.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Adenocarcinoma/pathology , Biomarkers, Tumor/analysis , Reference Values , Thymidylate Synthase/analysis , Immunohistochemistry , Adenocarcinoma/mortality , Proportional Hazards Models , Retrospective Studies , Longitudinal Studies , Tumor Suppressor Protein p53/analysis , Tissue Array Analysis , DNA-Binding Proteins/analysis , Cyclooxygenase 2/analysis , Kaplan-Meier Estimate , ErbB Receptors/analysis , MutL Protein Homolog 1/analysis , Neoplasm StagingABSTRACT
Abstract: Background: The studies found in the literature associate the immunoexpression of hMLH1 and hMSH2 proteins with histologic aspects, but do not correlate it with clinical and epidemiological data. Objective: To evaluate the immunoexpression of hMLH1 and hMSH2 in actinic cheilitis, correlating it with clinical characteristics. Methods: We analyzed 40 cases. Histological and immunohistochemical analyses were performed. The following clinical variables were evaluated: gender, age range, ethnicity, clinical aspect and occupational sunlight exposure. Statistical evaluation included the Student t-test, while the significance level was set at 5%. Results: Greater immunoexpression of hMLH1 and hMSH2 was observed in females, individuals aged over 40, and mixed-race/black patients. Furthermore, the immunoexpression of these proteins was greater in actinic cheilitis with a white-colored appearance and in patients without occupational sunlight exposure. No statistical differences were observed for the variables studied. Conclusion: This study uncovered variations of hMLH1 and hMSH2 protein expression upon evaluation of clinical aspects in actinic cheilitis.