Correlation between the immunohistochemical expressions of MMP-1, MMP-7 and VEGF and prognostic factors in colorectal adenocarcinoma

Abstract

Purpose: To analyze the expression of metalloproteinase-1, metalloproteinase-7 and vascular endothelial growth factor (VEGF) in colorectal adenocarcinoma, and to correlate these with the clinical-pathological prognostic factors. Methods: Tumor tissue from 82 patients was fixed in formalin and embedded in paraffin blocks. These samples were analyzed by means of the streptavidin-biotin immunohistochemical method, using the tissue microarray technique. Marker positivity was evaluated using categorical scores that determined cutoff percentages of stained tumor cells. Protein tissue expression was correlated with the variables of degree of cell differentiation, staging, disease-free interval, recurrence, survival and specific mortality. The Fisher exact and Kaplan-Meier tests were used to assess associations between the markers and the study variables. The log-rank and Wilcoxon tests were used to assess the significance of differences between curves of disease-free interval and survival. Results: All tumors were positive for metalloproteinase-1; 50 (61%) were positive and 32 (39%) were negative for metalloproteinase-7; and 60 (74.1%) were positive and 21 (25.9%) were negative for VEGF. Correlation of marker expression, both in groups and individually, did not show statistical significance in relation to the degree of cell differentiation, staging, disease-free interval, survival or specific mortality. Recurrence showed a statistically significant correlation with positive expression of the three markers, when analyzed as a group (p = 0.038). Conclusion: The associated expression of metalloproteinase-1, metalloproteinase-7 and VEGF in colorectal adenocarcinoma is related to the incidence of disease recurrence.