MicroRNA-124 and microRNA-378 inhibit the proliferation and invasion of colorectal cancer by upregulating KiSS1

BACKGROUND: The KiSS1 gene is considered a tumor suppressor in various cancers. MicroRNAs are involved in many important life processes, and their regulation of gene expression may be as important as that of transcription factors. Here, we explore the roles of miR-124-3p and miR-378-3p in colorectal cancer and their relationships with the KiSS1 gene. METHODS: The effects of miR-124-3p and miR-378-3p on KiSS1 protein expression were observed by transfecting colorectal cancer cells (SW-480) with miR-124-3p and miR-378-3p mimics and inhibitors. Moreover, cell proliferation, migration and invasion were evaluated by ethynyl-20-deoxyuridine and Transwell experiments. RESULTS: The KiSS1 mRNA and protein expression levels were significantly increased in mimic-transfected cells compared with those in untransfected cells, and the proliferation, migration and invasion abilities of the former were decreased; in addition, opposing results were obtained in the inhibitor and mimic groups. CONCLUSIONS: In conclusion, our studies indicate that miR-124-3p and miR-378-3p upregulate the expression of KiSS1 and are associated with colorectal cancer metastasis and progression. miR-124-3p, miR-378-3p and KiSS1 may play important roles in colorectal cancer.