miR-205 suppresses cell migration, invasion and EMT of colon cancer by targeting mouse double minute 4

Colon cancer is one of the most frequent malignant tumors, and microRNA (miR)-205 is involved in the tumor progression. The present study aimed to explore the effects of miR-205 on human colon cancer and its targeting mechanism. The levels of miR-205 and mouse double minute 4 (MDM4) were determined via reverse transcription-quantitative (RT-q)PCR and western blot analysis. A luciferase activity assay was performed to analyze the association between miR-205 and MDM4. Cell viability, migration and invasion were determined via Cell Counting Kit-8, wound healing and Transwell assays, respectively. The levels of epithelial-mesenchymal transition (EMT)-associated factors were determined by RT-qPCR and western blot analysis. It was identified that MDM4 was overexpressed in colon cancer tissues and cells, and that there was a negative correlation between miR-205 and MDM4 expression in colon cancer. Similarly, miR-205 inhibited MDM4 expression by binding to its 3′untranslated region. in addition, miR-205 directly targeted MDM4, accompanied by suppressed proliferation, migration and invasion of HCT116 cells. EMT processes were suppressed in miR-205-overexpressed cells; upregulation of E-cadherin, and downregulation of N-cadherin, vimentin, matrix metalloproteinase (MMP)2 and MMP9 were observed. Collectively, miR-205 conspicuously depressed the viability, migration, invasion and EMT process of human colon cancer cells via targeting MDM4. miR-205 could be potentially used in the treatment of human colon cancer.