Experimental models of pancreatic tumor stem cells
Pancreatic CSCs are characterized according to specific features. These include (I) self-renewal potential (by symmetric and asymmetric cell division), (II) differentiation potential for conversion into various types of cells of the tumor, (III) the ability of serial passaging in immunodeficient mice with subsequent recapitulation of the original tumor, (IV) the expression of specific surface markers (CD24, CD44, c-Met, EpCAM/ESA, CD133, CXCR4), which allow an assured identification and purification of CSCs. Additionally there is an increased activity of the CSC marker enzyme aldehyde dehydrogenase isoform 1 (ALDH1), as well as a pronounced resistance to the induction of programmed cell death, along with enhanced signaling signaling by the master NF-kB transcription factor, which activates signaling pathways of epithelial-mesenchymal transduction with increased cell motility and migration potential of tumor cells. Using these markers, we have characterized cells of pancreatic cancer and use these primary and established cells now as models for therapeutic studies in the petri dish or in in vivo tumor xenografts.