CELLULAR PHENOTYPES OF GLIOBLASTOMA AND PROGNOSIS OF TUMOR OUTCOME

Abstract

In solid malignant tumors, as well as in hematological tumors, cancer stem cells (CSCs), quiescent, pluripotent, self-renewing neoplastic, also known as tumor initiating cells, have been identified. CSC tumors are resistant not only to chemotherapy, but also to radiation therapy, as well as they play their role in the occurrence of relapses after surgical treatment, An unfavorable prognosis due to an aggressive course and complications after treatment of the most common primary brain tumor - glioblastoma multiforme (GBM), is also associated with CSC. One of the mechanisms that affect the physiological regeneration of tissues, but do not work under conditions of malignancy, is the environment and composition of the cellular tumor ensemble, represented by the phenotypes of cellular and adaptive immunity. Using immunohistochemical phenotyping methods, the authors identified immunocytes/phagocytes and established the features of their localization in the malignant tissue and at the border around the tumor. It was concluded that due to apoptosis around the tumor, intercellular signaling and migration of immunocytes/phagocytes to the focus of the tumor process are disrupted. The primary tumor process is not associated with damage to the tissue cambium genome, but with the migration of immature stem cells of the hematogenous pool, capable of proliferating and partially entering into incomplete differentiation under conditions of hypoxia and the absence of blood vessels. At the second stage, connective tissue is formed, which grows into vessels, the wall of which is represented by immature endothelium, with impaired transport function. According to the authors, metastasis of cancer cells does not occur by hematogenous and lymphogenous pathways, but is associated with the development of additional foci of hematopoiesis as a result of the adaptation of the human body to the loss of stem and semi-stem cells, precursors for normal regeneration of the nervous tissue.