To the best of our knowledge, this is the first review to systematically assess the in vitro and in vivo findings of DCLK1 studies with a focus on isoform-specific functions as well as prognostic values of each isoform, including DCLK1-S and DCLK1-L, among colorectal cancer patients, which makes the findings more robust. Here, DCLK1 is linked to colorectal cancer.