MicroRNA-383 suppresses cell proliferation and invasion in colorectal cancer by directly targeting paired box 6.

Colorectal cancer (CRC) is the third-most prevalent cancer and the fourth‑most common cause of cancer-associated fatality worldwide. The expression and biological roles of microRNAs (miRNAs/miRs) in tumourigenesis, and their regulatory function in a number of biological processes correlated with cancer have been investigated. miR‑383 has been reported to be deregulated in several human cancer types. However, the involvement and effects of miR‑383 on CRC progression and its underlying mechanism remain unknown. Therefore, the present study aimed to examine miR‑383 expression, investigate the biological functions of miR‑383 and identify its mechanism of action in CRC cells. In the present study, miR‑383 was significantly downregulated in CRC tissues and cell lines. Low miR‑383 expression was negatively associated with tumour size, lymph node metastasis and TNM stage. Function experiments demonstrated that miR‑383 upregulation inhibited the proliferation and invasion of CRC cells. Paired box 6 (PAX6) was confirmed as a direct target of miR‑383. PAX6 was upregulated in CRC tissues and was negatively correlated with miR‑383 expression. Induced PAX6 overexpression effectively rescued the tumour‑suppressing roles of miR‑383 on CRC cell proliferation and invasion. These findings suggested that miR‑383 may act as a tumour suppressor in CRC by directly targeting PAX6 and may serve as a promising therapeutic target for CRC treatment.