羟基喜树碱对人肺癌A549 细胞自噬的影响

Effect of hydroxycamptothecin on autophagy of A549 lung cancer cells

摘要:

目的 探究羟基喜树碱（HCPT）对人肺癌A549 细胞自噬的作用。方法 体外进行肺癌A549细胞的培养，分别使用50、200 和400μmol 的HCPT 处理，利用MTT 法检测HCPT 对细胞存活率的影响；共聚焦显微镜成像技术观察HCPT 对细胞自噬活性的影响；Western blot 检测HCPT 对自噬相关蛋白LC3、p-mTOR 表达的影响。结果 HCPT 抑制A549 细胞的活性；HCPT 处理24 h 后细胞质和细胞核周围Cyto-ID 绿色荧光强度增强；与对照组比较，HCPT 治疗各组LC3II/I 值升高，p-mTOR 表达减少；且加入自噬抑制剂6- 氨基-3- 甲基嘌呤（3-MA）处理后的各组与相对应的HCPT 治疗各组比较，A549 细胞的增殖抑制增强。结论 HCPT 能抑制A549 细胞增殖并诱导其发生自噬；HCPT 发挥抑制A549 细胞增殖作用可能与自噬密切相关；抑制细胞自噬可能会增强HCPT 的抗A549 细胞增殖能力。

Abstract:

Objective To investigate whether autophagy is involved in the anticancer mechanisms of hydroxycamptothecin (HCPT) in human lung cancer A549 cells in vitro. Methods Human non-small cell lung cancer cell line A549 was cultured. In our study, cell viability was assessed by MTT assay, Cyto-ID staining was used for autophagy detection which was observed by laser scanning confocal microscope (LSCM), the expression of LC3II/I and p-mTOR were measured by Western blot. Results HCPT (50, 200 and 400 μmol) suppressed the viability of A549 cells in a concentration-dependent manner. Moreover, HCPT increased autophagy level in the A549 cells. The autophagy inhibitor 3-MA caused a statistically significant increase in growth inhibition of the HCPTtreated A549 cells. Conclusions HCPT induces autophagy in lung cancer A549 cells in vitro. HCPT (50, 200 and400 μmol) suppresses the viability of A549 cells in a concentration-dependent manner and its induction of cell autophagy is related to the dosage. Autophagy inhibition combined with HCPT may be a better way for the treatment of lung cancer.