miR‑218 promotes apoptosis of SW1417 human colon cancer cells by targeting c‑FLIP

: MicroRNAs (miRNAs) are suggested to act as either tumor oncogenes or tumor suppressors in different types of cancer. miRNA‑218 (miR‑218) is a type of short, non-coding RNA which is involved in gastric cancer development. In the present study, we evaluated the functions of miR‑218 in SW1417 human colon cancer cells and its potential mechanisms. Following overexpression of miR‑218 in human colon cancer cells, cell viability was determined by CKK‑8 assay, cell apoptosis was observed using a TUNEL Kit, the expression of caspase‑8, and its inhibitor cellular Fas‑associated death domain‑like interleukin‑1β‑converting enzyme inhibitory protein (c‑FLIP) was assessed by RT‑PCR, western blot analysis and immunohistochemistry. The results indicated that miR‑218 and caspase‑8 expression was decreased while c‑FLIP expression was elevated in human colon cancer tissues. In cultured SW1417 human colon cancer cells, miR‑218 overexpression potently inhibited cell viability and promoted cell apoptosis. Furthermore, downregulation of c‑FLIP expression and upregulation of caspase‑8 expression were detected in miR‑218‑stimulated SW1417 cells. In addition, following the knockdown of c‑FLIP using c‑FLIP siRNA, the apoptotic effects of miR‑218 on SW1417 cells were significantly reduced. Collectively, the present study demonstrated that miR‑218 induced the apoptosis of SW1417 cells by targeting c‑FLIP. Therefore, miR‑218 may represent a potential therapeutic method for screening and treating colon cancer.