DLL4 and pancreatic neoplasm: In pancreatic cancer cells, DAPT-induced Notch downregulation led to a reduction in the number of CD133+, the inhibition of cell proliferation, and abrogation of the DLL4/Notch-induced chemo-resistance [138], and also resulted in apoptosis, the inhibition of EMT, and the suppression of tumorigenesis by eliminating pancreatic cancer-initiating cells (CD44+/EpCAM+), both in vitro and vivo [139].