miR-155参与缺氧诱导的乳腺癌化疗耐药

MiR-155 Participates in the Breast Cancer Chemoresistance Induced by Hypoxia

[目的]探讨miR-155在缺氧诱导的乳腺癌化疗耐药中的作用。[方法]以0、50、100、150、200μmol/L不同浓度CoCl_2处理4T1细胞,建立缺氧模型。实时定量PCR检测缺氧条件下miR-155的表达与耐药基因BCRP的表达。通过慢病毒载体转染使miR-155过表达,通过caspase3/9分光光度法探讨miR-155在缺氧环境下乳腺癌化疗耐药中的作用。[结果]随缺氧程度的增加,miR-155及BCRP基因表达增加,过表达miR-155可抑制阿霉素诱导的4T1细胞的凋亡。[结论]随着乳腺癌缺氧程度加重,miR-155表达逐渐增加,miR-155表达与乳腺癌化疗耐药相关。

：[Purpose] To investigate the effect of miR-155 on the drug resistance of breast cancer. [Methods] 4T1 cells were treated by 0,50,100,150,200μmol/L CoCl2. Real time quantitative PCR was conducted to detect the expression of miR-155 and BCRP,a drug resistance gene,under hypoxic condition. To further explore the role of miR-155 in chemoresistance,a lentiviral vector carrying miR-155 precursor was transfected into 4T1 cells. Then the caspase 3/9 activity was conducted by spectrophotometric method. [Results] With the increase of hypoxia,the expression of miR-155 and BCRP gene increased. Over expression of miR-155 repress apoptosis induced by doxorubicin.[Conclusion] With the increasing of hypoxia,the expression of miR-155 increases. MiR-155 expression is associated with chemotherapy resistance in breast cancer.