Cancer Angiogenesis and Opportunity of Influence on Tumor by Changing Vascularization

Abstract

Based on the study of recent scientific literature devoted to neovascularization and angiogenesis in malignant neoplasms, it was concluded that there are many publications on each of the problems of tumor angiogenesis and vascularization. The formation of blood vessels in a tumor and certain aspects of the prognostic value of the severity of vascularization in almost all forms of cancer are considered. Special attention is paid to the peculiarities of angiogenesis in tumors of the female reproductive system. A large number of vessels in the tumor often indicates a poor prognosis. The influence of various factors on the initiation of angiogenesis and the process itself, as well as the possibility of suppressing such signals to slow down the formation of blood vessels and thus the development of the tumor are widely studied. The results of pharmacological suppression of tumor vessel formation demonstrate a good clinical outcome but one accompanied by a large number of severe adverse side effects. Such a significant amount of studies on each of the problems of tumor vascularization indicates the increasing importance of this area of oncology. At the same time, only a very small number of works are devoted to the study of the differences in angiogenesis and number of vessels between different parts of the tumor, as well as between the primary tumor node and its metastases. The refinement of the results is still to be done. It was noted that the expression of proangiogenic factors in metastases is usually higher than in the source of metastasis, and the expression in lymphogenous metastases is higher than in hematogenous ones.

Keywords: angiogenesis; cancer; tumor; vascularization; vasculogenesis; vessels.

Figure 1

Human axillary LN. Immunohistochemical reaction with CD34 antibodies stained with diamidobenzidine and hematoxylin: (a) control LN, few CD34+ vessels in the superficial part of the cortex and paracortex, waste areas of the cortical substance free from CD34+ structures; (b) control LN, due to the postmortem changes, the medullary cords and sinuses lost well-defined structure, cell composition rare, single CD34+ vessels located at the edge of cords and sinuses, no CD34+ structures observed in the huge areas of the medullary substance; (c) LN at BC stage IIIa, small CD34+ vessels infiltrate practically the total cortical substance, walls of these vessels consist of one cell layer. (d) LN at BC stage IIIa, small CD34+ vessels infiltrate practically the total medullar substance of parenchyma [8,9].

Figure 2

Schematic of the tumor angiogenesis.