Delta-like homologue 1 (DLK1) is a transmembrane protein that belongs to the NOTCH non-canonical ligand family and plays an important role in the regulation of stem cell pools, tissue differentiation during development, cancer differentiation, and cancer stem-like cell (CSCs) maintenance.1, , , , , , , , , –11 It is coded by a maternally imprinted, paternally expressed gene localized on chromosome 14 in human and chromosome 12 in mouse.2,12, –14. This evidence concerns the gene DLK1 and cancer.