Later on, many studies based on several xenograft models identified other markers for pancreatic cancer stem cells such as CD133, c-Met, ALDH1 (aldehyde dehydrogenease-1), Lgr5 (leucine-rich repeat-containing G-protein coupled receptor 5), and DclK1 (doublecortin-like kinase 1) (Figure 1) [17, 47–54], although further studies will be necessary to better define the cell surface markers of PCSCs. This evidence concerns the gene DCLK1 and familial pancreatic carcinoma.