DLL4 and breast cancer: In the next work of the same research group [179], FKBPL-derived peptides (AD-01, preclinical peptide/ALM201, clinical peptide) were successfully used to reduce the numbers of CSCs and suppress the metastatic ability in MCF-7 and MDA-MB-231 breast cancer lines; the achieved effects were accompanied by significant impairment of cancer cell migration/invasion and downregulation of DLL4 and Notch4.