With respect to DCLK1 surface expression, many cancer cell lines express low levels of extra cellular isoforms 2 and 4 (e.g., BxPC3 and MIA PaCa-2 pancreatic cancer cell lines); however, in this report, we describe three cancer cell lines that express greater than 9 percent DCLK1 cell surface expression at baseline: HT29, HCT116, and LoVo cells. Here, DCLK1 is linked to cancer.