microRNA干扰抑制MTDH的表达对乳腺癌细胞MDA-MB-231增殖和侵袭能力的影响

目的 探讨microRNA干扰技术沉默异黏蛋白（MTDH，metadherin蛋白）基因表达及对人乳腺癌细胞MDA-MB-231细胞增殖、转移、侵袭能力的影响。方法 将人工合成的针对MTDH基因的miRNA片段瞬时转染人乳腺癌细胞MDA-MB-231，通过Western blot法、RT-PCR法检测MTDH蛋白表达和MTDHmRNA；应用MTT检测法、划痕实验、Transwell实验检测抑制MTDH基因后对乳腺癌细胞增殖、转移、侵袭能力的影响。结果 MTDHmiRNA能有效抑制MTDH蛋白和MTDHmRNA表达，最佳抑制率分别为79.41%、80.56%（P<0.05）；经miRNA干扰的细胞，生长速度明显受到抑制（P<0.05），侵袭迁移能力显著下降（P<0.05）。结论 MTDH miRNA瞬时转染人乳腺癌MDA-MB-231细胞可明显抑制癌细胞中MTDH表达，沉默MTDH基因表达后可明显抑制人乳腺癌MDA-MB-231细胞生长增殖、侵袭迁移能力。

Influence on Proliferation and Invasion of Human Breast Carcinoma Cell Line MDA-MB-231 by Using MicroRNA Interference Technique to Suppress MTDH Expression

Objective To investigate the effects of RNA interference technique silencing MTDH on proliferation, metastasis and invasion of human breast cancer cell MDA-MB-231. Methods The MTDH miRNA was transfected into Human breast cancer cell MDA-MB-231 by means of lipofectamine 2000. The silencing efficiency of MTDH was examined by RT-PCR and western blot. The influence of MDA-MB-231 cell proliferation, metastasis and invasion ability from inhibition MTDH gene was conducted by using MTT assay, scratch experiments, and Transwell assay. Results MTDH miRNA effectively inhibited MTDH mRNA and protein levels. The best inhibition rate were 79.41% and 80.56% (P<0.05).With miRNA interferring cells,the ability of cells proliferation was decreased (P<0.05),and cells invasive and metastasis were depressed (P<0.05). Conclusion MTDH expression is obviously suppressed after transfected by MTDH miRNA in MDA-MB-231 cells. The inhibition of MTDH expression from microRNA leads to significant suppression of proliferation, invasion and metastasis of breast cancer cell MDA-MB-231.