Angiogenesis in the Uterus: Potential Regulation and Relation to Tumor Angiogenesis

Abstract

Except under certain pathological conditions such as wound healing and solid tumor growth, angiogenesis is a relatively rare event in the adult. One exception, however, is the angiogenesis that occurs during the cyclical changes in the female reproductive tract. Many factors, chemical as well as mechanical, have been shown to be capable of promoting or inhibiting angiogenesis in vivo and in vitro. However, despite intense research efforts, the mechanisms involved in the regulation of angiogenesis in vivo are not fully understood. In this article we briefly review the basic steps involved in angiogenesis and present examples of factors and conditions that may serve as potential regulators of angiogenesis in the nonpregnant uterus. Finally, we discuss some of the architectural, anatomical, and physiological differences between the microcirculatory beds established during normal, self-limited vessel growth and that associated with the uncontrolled, pathological vascular growth that accompanies tumor growth and metastasis.

Angiogenic factors in relation to embryo implantation

“…These two physiologically coordinated processes are needed for embryo implantation and growth and different from those occurring in tumors. 68 These results support the fact that angiogenesis is an important element for normal implantation and indicates the importance of the vasculature in early stages of pregnancy.…”

“…67,68 Among all pregnancy related disorder, the implantation failure considers to be important due to loss of endometrial receptivity resulted from poor or abnormal angiogenesis. Development of the blood vessels in the endometrium through a regulated angiogenesis in the endometrium is an essential requirement for fetal implantation.…”

Light Optical Study of Human Breast Cancer Tissue Embedded in Epoxy Rezins

“…13 A useful method of angiogenesis estimation in human tumors is the microvessels counting method in the primary tumor using specific markers of endothelial cells such as VIII-factor, CD31, CD34, as well as the standard immunoperoxidase technique of vessels staining. 16,21,22 The studies on antibodies to CD31 factor was proved to be more sensitive method as the available panendothetial markers. This method recognizes more microvessels as other endothelial markers.…”

“…3,10 In spite the fact that capillary net around the tumor formed by normal endothelial cells, it is quite different from capillaries which have normal morphology, density and penetration. 21 The dense capillary net provides enough oxygen and necessary nutrients to developing tumor cells, as well as moves out the products of cells metabolism. The presence of capillary net leads to easier dissemination of metastatic tumor cells.…”

Keratin 17 identified by proteomic analysis may be involved in tumor angiogenesis

“…The induction of tumor angiogenesis is mediated by the release of angiogenic factors (24). Among these factors, bFGF is a wide-spectrum angiogenic factor shown to induce migration of endothelial cells both in vivo and in vitro (5).…”