MicroRNA-330-5p negatively regulates ITGA5 expression in human colorectal cancer

Colorectal cancer (CRC), one of the most prevalent malignant cancers, has high rates pf incidence and is the fourth leading cause of cancer-related deaths for both men and women worldwide. MicroRNAs (miRNAs) play critical roles in the development of various types of cancers. miRNA-330-5p has been implicated in the progression of prostate, neuronal and pancreatic cancers by regulating proliferation, migration, invasion and epithelial-mesenchymal transition of cells. The purpose of the present study was to investigate the expression of miR-330-5p in CRC and identify its target gene(s) that may act in CRC tumorigenesis. We found that miR-330-5p expression was significantly lower in CRC tissues than that in adjacent non-tumorous tissues. Furthermore, we identified integrin alpha 5 (ITGA5) as a new target of miR-330-5p and found that it inhibits ITGA5 expression by directly binding to the 3' untranslated region of ITGA5 mRNA. These results suggest that downregulation of miR-330-5p expression may. affect CRC development via modulation of ITGA5 expression.