ABSTRACT
<p><b>OBJECTIVE</b>To investigate the regulatory effect of miR-29b on gastric cells' resistance to cisplatin.</p><p><b>METHODS</b>The expression of miR-29b in gastric cancer cell line treated with cisplatin concentration gradient was detected using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blotting. CCK8 was used to measure the cell viability after cisplatin treatment in condition of miR-29b knock-down and overexpression.</p><p><b>RESULTS</b>The expression of miR-29b was significantly upregualted by cisplatin treatment,while its target gene AKT2 was downregulated. The up-regulation of miR-29b enhanced the sensitivity of gastric cancer cells to cisplatin,while the knock-down of miR-29b enhanced the cisplatin resistance. Rescue experiments demonstrated that the miR-29b might regulate cisplatin resistance of gastric cancer cell by targeting PI3K/Akt pathway. The expressions of the other two members of miR-29 family, miR-29a/c, were promoted by cisplatin treatment,but they had no significant effect on gastric cancer cell's resistance to cisplatin.</p><p><b>CONCLUSION</b>miR-29b can enhance the sensitivity of S gastric cancer cell by directly targeting PI3K/Akt pathway.</p>