Timosaponin AIII (TAIII), an active component with anti-tumor activity from Anemarrhena asphodeloides Bunge, can induce both autophagy and apoptosis of cancer cells. The present study aimed to reveal the promoting or inhibiting role of TAIII-induced autophagy on TAIII-induced apoptosis, to determine the respective upstream signaling pathways for TAIII-induced autophagy and apoptosis; and to observe the therapeutic potential of TAIII in human non-small cell lung cancer . WST-1 assay was used to determine the effect of TAIII on cell growth and proliferation. Apoptosis was detected by DAPI staining and flow cytometry. Autophagy was verified by immunofluorescence and transmission electron microscopy. Western blot was used to determine the levels of protein expression. Furthermore, the anti-tumor activity of TAIII was observed in nude mice. TAIII at high concentrations from 10 μM to 30 μM induced both autophagy and apoptosis in human non-small cell lung cancer cells in a time- and concentration-dependent manner. TAIII at low concentration (1 μM) only induced autophagy. The AMP-activated protein kinase (AMPK) signaling pathway was identified to be responsible for TAIII-induced autophagy both at high or low concentrations. The MAPK/Erk1/2 signaling pathway was identified to be responsible for TAIII-induced apoptosis at the high concentration (20 μM). TAIII-induced autophagy protected cancer cells from apoptosis, and combination of TAIII and autophagy inhibitor showed higher anti-cancer activity.

中文翻译：

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抑制自噬增强知莫皂苷AIII诱导的肺癌细胞凋亡及体内外抗肿瘤作用

Timosaponin AIII (TAIII) 是知母中具有抗肿瘤活性的活性成分，可诱导癌细胞自噬和凋亡。本研究旨在揭示TAIII诱导的自噬对TAIII诱导的细胞凋亡的促进或抑制作用，明确TAIII诱导的自噬和细胞凋亡各自的上游信号通路；并观察TAIII对人非小细胞肺癌的治疗潜力。 WST-1测定用于确定TAIII对细胞生长和增殖的影响。通过DAPI染色和流式细胞术检测细胞凋亡。通过免疫荧光和透射电子显微镜验证自噬。蛋白质印迹用于测定蛋白质表达水平。此外，在裸鼠中观察到TAIII的抗肿瘤活性。 10 μM 至 30 μM 高浓度的 TAIII 以时间和浓度依赖性方式诱导人非小细胞肺癌细胞自噬和凋亡。低浓度（1 μM）的TAIII仅诱导自噬。 AMP 激活蛋白激酶 (AMPK) 信号通路被确定负责高浓度或低浓度 TAIII 诱导的自噬。 MAPK/Erk1/2 信号通路被确定与高浓度 (20 μM) TAIII 诱导的细胞凋亡有关。 TAIII诱导的自噬保护癌细胞免于凋亡，TAIII与自噬抑制剂的组合显示出更高的抗癌活性。