Proliferative activity of cancer stem cells in the prognosis of hematogenous metastasis of colon adenocarcinoma

Abstract

The search for prognostic markers to determine the risk of dissemination and metastasis of colon adenocarcinoma is one of the most difficult and actual problems of modern oncomorphology.The aim of this work was to determine the possibility of using indicators of the proliferative activity of cancer stem cells in the prediction of hematogenous metastasis of colon adenocarcinoma. In this work the surgical material from 32 radically operated patients of different ages suffering from a localized colon adenocarcinoma was explored, and relapse-free survival was assessed. A comparative analysis of various components of the tumor differon, including proliferating stem cells and their relationship with the formation of relapse was carried out.An index of stem cell proliferation was proposed to assess the influence of stem cell activity on the biological behavior of tumor. The best rates of relapse-free survival were found in the group of patients with low value of the index of stem cell proliferation compared with patients which index took on high values, which is more typical for elderly and old patients. With a similar comparison of other indicators of tumor differon, including the percentage of ALDH1 and Ki-67-positive cells, as well as cells with the ALDH1+Ki-67+immenophenotype relative to the total tumor differon, no significant relationship with relapse-free survival was found. These results may indicate a high role of ALDH1+ cell proliferation in tumor dissemination, especially in elderly and senile patients, and a lesser influence of both the proliferative activity of Ki-67 and the general population of stem cells on the formation of distant metastases.