Comparative immunohistochemical study of proliferation and apoptosis in colorectal adenocarcinoma

Abstract

Colorectal cancer is the actual problem in the global health care system, which is associated with high rates of morbidity and mortality. Aim. To compare the expression levels of immunohistochemical markers of proliferation and apoptosis in the colorectal tumor cells and the colorectal tumor-associated stroma; to study the correlations between the proliferation levels, apoptosis levels and clinicopathological parameters of colorectal adenocarcinoma. Materials and methods. The surgical material of 30 patients with distal colon adenocarcinoma (I-IV clinical stages) was analyzed using pathohistological and immunohistochemical methods. Results. It was established that colorectal tumor cells are characterized by the medium proliferation level, the medium p53 expression level and the low apoptosis level, just as colorectal tumor-associated stroma is characterized by the low proliferation, p53 expression and apoptosis levels. The direct strong correlations between the proliferation and apoptosis levels in the tumor cells, and also between the proliferation and apoptosis levels in the tumor-associated stroma were revealed. The direct medium correlations between the p53 expression levels in the tumor cells and the tumor-associated stroma, between the p53 expression level in the tumor cells and the Ki-67 expression level in the tumor-associated stroma, and also between the p53 expression level in the tumor cells and the degree of histological differentiation of the tumor were revealed. Moreover, the reverse strong correlations between the Ki-67 expression levels and the caspase-3 expression levels in the tumor cells and the tumor-associated stroma were revealed. Conclusions. These data indicate the tight association between proliferative and apoptosis processes in the colorectal tumor cells and the colorectal tumor-associated stroma. The interconnections between the p53 accumulation in the tumor cells and the colorectal tumor-associated stroma, the p53 accumulation in the tumor cells and the increase of proliferative activity of the colorectal tumor-associated stroma, and also between the p53 accumulation in the tumor cells and the degree of histological differentiation of the tumor were established. Furthermore, it was revealed that increase of proliferative activity of colorectal adenocarcinoma is associated with decrease apoptotic activity of the tumor.