[A tumor stem cell-specific marker identified by lineage tracing in the intestine].

Tumor therapies targeting tumor stem cells(TSCs) have been limited. One of the reasons is that TSC markers are often shared by normal stem cells (NSCs), and therapies targeting those marker-positive cells may cause severe injury to normal tissues. To solve the problem, we focused on doublecortin -like kinase 1 (Dclk1). In the normal intestines of Dclk1(creERT2/+); Rosa26(LacZ/+) mice, LacZ-labeled epithelial cells were scattered along villi after tamoxifen injection. In contrast, in Dclk1(creERT2/+); Rosa26(LacZ/+); Apc(Min/+) mice, intestinal tumors were occupied by LacZ-labeled tumor cells, and selective ablation of Dclk1-positive cells using iDTR system resulted in regression of intestinal tumors without apparent damage to the normal intestines. Thus, Dclk1 appeared to be a marker that discriminates TSCs from NSCs in the intestine.