Mir-4746 inhibits the proliferation of colorectal cancer cells in vitro and in vivo by targeting CCND1

Colorectal cancer (CRC) is a commonly seen malignant tumor manifesting itself in the digestive tract, but it remains unclear what is the molecular mechanism behind its occurrence and development, which can have a significant impact on the clinical diagnosis and treatment of CRC. According to some studies, microRNA (miRNA) plays an essential role in the occurrence and development of cancer. In spite of this, there are still many miRNAs that play an important role in the progression of CRC but have yet to be reported. In our research, it was found out that the expression of mir-4746 is significantly down-regulated in CRC tissues and cells, and that its expression level is closely associated with the tumor size and prognosis of clinical patients. As revealed by function and mechanism experiments, targeting CCND1 mRNA 3'-UTR, mir-4746 can promote the degradation of CCND1 mRNA, thus reducing the protein level of CCND1, leading to cell G0-G1 phase arrest, and ultimately inhibiting the proliferation of CRC cells. For the first time, our study reported the biological functions of mir-4746 and its preliminary mechanism of action, in addition to demonstrating that mir-4746 can be applied as both a potential prognostic marker and the therapeutic target for CRC.