低氧环境下肺腺癌A549细胞自噬及miR-155表达变化的研究

目的观察低氧环境下培养人肺腺癌A549细胞自噬及miR-155表达的变化,为探讨miR-155与自噬关系的研究奠定基础。方法分别在常氧（20%O2/5%CO2/75%N2）（常氧组）及低氧（1%O2/5%CO2/94%N2）（低氧组）环境下培养A549细胞,采用电镜检测自噬体变化,Western blot检测自噬标记蛋白LC3蛋白表达,分析LC3Ⅱ/LC3Ⅰ比值变化,Real-Time PCR检测miR-155表达变化。结果与常氧组相比,低氧组LC3Ⅱ/LC3Ⅰ增加（0.46±0.03）倍;低氧组miR-155表达上调,于24、48 h分别增加（1.45±0.23）倍及（2.10±0.32）倍。结论在低氧环境中,A549细胞中miR-155表达上调,保护性自噬增加。

A549 Cell Autophagy and Change in miR-155 Expression under Hypoxic Condition

Objective To investigate the autophagy in human lung adenocarcinoma A549 cells and the change in miR-155 expression under hypoxic condition, and to lay the foundation for the study of the relationship between miR-155 and cell autophagy. Methods A549 cells were cultured under normoxic（20% 02,5% C02 and 75% NE）or hypoxie conditions（1% 02,5% C02 and 94%N2）. Changes in autophagosomes were observed under electron microscopy. The expression of LC3 was examined by Western blot and LC3 Ⅱ/LC3 I ratio was measured. The expression of miR-155 was detected by Real- Time PCR. Results Compared with normoxic condition,LC3 Ⅱ/LC3 I ratio increased by （0.46±0.03） times,and miR-155 expression incre-ased by（1.45±0.23）and（2.10±0.32）times at 24 and 48 hours, respectively. Conclusion Hypoxia ind-uees protective autophagy and up-regulation of miR-155 expression in A549 cells.