Abstract: Endometriosis is a complex disease with a multifactorial pathogenesis, which is crucially dependent on the neovascularization. The present review highlights the fact that the neovascularization of endometriotic lesions is not only driven by angiogenesis, but also involves de novo formation of microvessels from circulating endothelial progenitor cells (EPC). This process, termed vasculogenesis, is a characteristic of various pathogenic conditions, such as tumour growth and atherosclerosis, and typically comprises the activation, mobilization and recruitment of bone marrow-derived EPC to the sites of tissue hypoxia. Recent studies indicate that part of the microvascular endothelium of ectopic endometrial tissue originates from EPC, and controlled by the stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor type 4 (CXCR4) axis. Accordingly, blockade of EPC recruitment effectively inhibits the formation of microvascular networks in developing endometriotic lesions, indicating that vasculogenesis represents an integral part of the pathogenesis of endometriosis. The involvement of vasculogenesis in endometriosis may offer the exciting opportunity for the future establishment of novel diagnostic and therapeutic strategies for this frequent gynecological disease.

Key words: Endometriosis, Stem cells, Neovascularization, pathologic