title: The spermatogonial stem cell niche in testicular germ cell tumors.
abstract: Spermatogonial stem cells (SSCs) are pluripotent elements found in the adult seminiferous epithelium between Sertoli cells and a basal lamina which covers the multilayered external wall of peritubular myoid cells. The microenvironment of this pluripotent stem cell niche creates the complex and dynamic system that is necessary for the initiation of spermatogenesis, but this system also contains factors which can potentially collaborate in the progression of testicular germ cell tumors (TGCTs). In this review, we summarize our current knowledge about some important structural and molecular features related to the SSC niche, including growth factors, adhesion molecules, extracellular matrix, mechanical stress and vascularization. We discuss their possible collaborative effects on the generation and progression of TGCTs, which are a type of cancer representing the most frequent neoplasia among young men and whose incidence has grown very quickly during the past decades in North America and Europe. In this regard, a better understanding of the pluripotent stem cell niche where these malignancies arise will provide further insights into the origin of TGCTs and the mechanisms underlying their growth and invasion of adjacent and distant tissues.
authors.affiliation: Laboratory of Stem Cells, Development and Cancer, Department of Cell Biology and Histology, University of the Basque Country, Vizcaya, Spain.
authors.forename: Unai
authors.initials: U
authors.lastname: Silván
authors.forename: Alejandro
authors.initials: A
authors.lastname: Díez-Torre
authors.forename: Pablo
authors.initials: P
authors.lastname: Moreno
authors.forename: Jon
authors.initials: J
authors.lastname: Arluzea
authors.forename: Ricardo
authors.initials: R
authors.lastname: Andrade
authors.forename: Margarita
authors.initials: M
authors.lastname: Silió
authors.forename: Juan
authors.initials: J
authors.lastname: Aréchaga
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D005854:Germ Cells / Q000166:cytology* / Q000502:physiology; D006801:Humans; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000473:pathology*; D013091:Spermatogenesis / Q000502:physiology*; D055153:Stem Cell Niche / Q000502:physiology*; D013736:Testicular Neoplasms / Q000473:pathology*