Steroid Hormone Regulation of Vascular Endothelial Growth Factor (VEGF) Production: A Potential Step in Hormonal Carcinogenesis

The provision of a sufficient nutrient supply is a basic requirement for the growth, replication, and performance of differentiated function of all cells. In mammalian tissues the supply of nutrients is regulated largely by the vascular system, and some of the most dramatic changes in the mammalian vasculature occur in the female reproductive tract. These include both the growth of blood vessels such as that observed in the primate endometrium during the menstrual cycle, as well as changes in vascular permeability that regulate the transit of water, small molecules, and proteins from vessels to the intracellular space. In the physiological setting, these vascular effects are regulated largely by the cyclical secretion of ovarian steroid hormones, and these events can be mimicked experimentally by the administration of exogenous estrogens (E) and progestins. Understanding the underlying mechanisms by which steroid hormones regulate vascular events has received considerable attention, since these changes are likely essential for normal endometrial growth and successful implantation.