MiR‑224 promotes colorectal cancer cells proliferation via downregulation of P21WAF1/CIP1.

MicroRNAs (miRNAs) are between 19 and 25 mer non‑coding RNAs involved in cancer cell proliferation, apoptosis, stress responses and maintenance of stem cell potency. In the present study, miR‑224 was observed to be upregulated in colorectal cancer (CRC) tissue. Overexpression of miR‑224 facilitated proliferation of the CRC cell lines, HCT‑116 and SW‑480. Bioinformatics analysis revealed a putative miR‑224 binding site in the 3'‑untranslated region of CDKI1A (P21WAF1/CIP1). Western blot analysis and the luciferase reporter assay proved that miR‑224 represses P21WAF1/CIP1 expression and promotes cell cycle G1/S transition. These results suggest that the downregulation of miR‑224 in CRC is a novel potential therapeutic strategy.