Gene expression profile of Dclk1⁺ cells in intestinal tumors

Accumulating evidence has shown the existence of tumor stem cells with therapeutic potential. Previously, we reported that doublecortin like kinase 1 (Dclk1) marks tumor stem cells but not normal stem cells in the intestine of Apc^Min/+ mice, and that Dclk1- and Lgr5-double positive tumor cells are the tumor stem cells of intestinal tumors.

To investigate molecules highly expressed in the Dclk1⁺ normal intestinal and Dclk1⁺ tumor cells in Apc^Min/+ mice.

We used microarray analyses to examine the gene expression profile of Dclk1⁺ cells in both mouse normal intestinal epithelium and Apc^Min/+ mouse intestinal tumors. We also performed immunofluorescence analyses.

Genes related to microtubules and the actin cytoskeleton (e.g., Rac2), and members of the Src family kinases (i.e., Hck, Lyn, Csk, and Ptpn6) were highly expressed in both Dclk1⁺ normal intestinal and Dclk1⁺ tumor cells. Phosphorylated Hck and phosphorylated Lyn were expressed in Lgr5⁺ cells in the intestinal tumors of Lgr5^{EGFP-IRES-CreERT2/+}; Apc^Min/+ mice.

We revealed factors that are highly expressed in Dclk1⁺ intestinal tumor cells, which may help to develop cancer stem cell-targeted therapy in future.