MicroRNA-30a-5p suppresses tumor cell proliferation of human renal cancer via the MTDH/PTEN/AKT pathway

The present study aimed to explore the effects of microRNA (miRNA)-30a-5p on tumor proliferation and to seek a potential therapeutic target for the treatment of human renal cancer. The results demonstrated that the expression levels of miRNA-30a-5p were reduced in tumor samples from patients with renal cancer compared with in normal tissue samples. Overall survival and disease-free survival were increased in patients with renal cancer and high miRNA-30a-5p expression compared with in those with low miRNA-30a-5p. Furthermore, overexpression of miRNA-30a-5p suppressed cell proliferation, induced apoptosis, and promoted caspase-3/9 activities and B-cell lymphoma 2-associated X protein (Bax) protein expression in Caki-2 cells. In addition, the results confirmed that overexpression of miRNA-30a-5p inhibited metadherin (MTDH), upregulated phosphatase and tensin homolog (PTEN) and suppressed phosphorylated (p)-protein kinase B (AKT) protein expression levels in Caki-2 cells. Furthermore, transfection with small interfering RNA-MTDH, increased the effects of miRNA-30a-5p on the inhibition of cell proliferation, and promotion of apoptosis, caspase-3/9 activities and Bax protein expression levels in Caki-2 cells. Knockdown of MTDH expression also upregulated PTEN and suppressed p-AKT protein expression in Caki-2 cells. In conclusion, the present study is the first, to the best of our knowledge, to provide evidence suggesting that miRNA-30a-5p suppresses tumor human renal cancer cell proliferation via the MTDH/PTEN/AKT pathway.