L1CAM and neoplasm: The use of various specific surface markers or molecular mediators such as prominin-1 (CD133), cluster of differentiation 90 (CD90), cell surface glycoprotein CD44 (CD44), L1 cell adhesion molecule (L1CAM), and glycerol-3-phosphate dehydrogenase 1 (GPD1) is a common approach to identify GSCs and define lineage-specific subpopulations within the tumor [16] and also offers new directions for the development of modern therapies.