It has been found that miR‐21 may promote CRC cell proliferation and invasion by down‐regulating PTEN protein expression.15, 17 Here, our results confirmed that miR‐21 significantly reduced PTEN levels in SW620 and LoVo cells by directly targeting its 3′UTR using luciferase reporter and Western blotting assays (Figure S1A,B). Here, PTEN is linked to colorectal carcinoma.