山木瓜来源化合物Griffipavixanthone调节自噬和钙离子抑制肿瘤细胞生长

Griffipavixanthone Inhibits the Growth of HeLa Cells via Suppressing Autophagy Flux and Calcium Level

目的:本文主要探索藤黄属植物山木瓜中提取的天然小分子化合物Griffipavixanthone对肿瘤自噬的影响和作用机制。方法:以宫颈癌He La细胞株为体外研究模型,通过共聚焦显微术,流式细胞术和蛋白免疫印迹法检测Griffipavixanthone对自噬和钙离子信号通路的影响;同时使用裸鼠荷瘤模型,探索Griffipavixanthone体内的抗肿瘤作用。结果:Griffipavixanthone浓度和时间依赖增加细胞内GFP-LC3点状结构,诱导LC3 I至LC3 II的转变,增加SQSTM1蛋白含量;同时,Griffipavixanthone显著抑制He La细胞生长,并且在营养缺乏情况下,可以加速细胞死亡;此外,Griffipavixanthone可以下调细胞内钙离子的浓度;最后体内实验表明Griffipavixanthone具有一定的抗肿瘤效果。结论:体内体外的研究结果表明Griffipavixanthone具有抗肿瘤作用,其作用机制可能和Griffipavixanthone抑制自噬通量和钙离子内流相关。

This study aimed at exploring the effects of Griffipavixanthone, a natural small molecule extracted from Garcinia esculenta, on the autophagy and the mechanism behind it. Cervical cancer He La cells were selected as the model in vitro. Confocal microscopy, flow cytometry and immunoblotting were performed to know the impacts of Griffipavixanthone on signaling pathway over autophagy flux and calcium level; while nude mouse model was established to explore its anti-cancer action in vivo. It was found that Griffipavixanthone significantly induced GFP-LC3 puncta formation and the accumulation of LC3-II/LC3-I, and increased the protein expression of SQSTM1 in He La cells in a time and concentration dependent manner. MTT assay results showed that Griffipavixanthone inhibited the growth of He La cells in a dosage dependent manner, and eliminated the tolerance of tumor cells to nutrient starvation, which fastened the death of cells. Griffipavixanthone also down-regulated the concentration of calcium in the cytoplasm.Furthermore, the in vivo study indicated that intratumoral injection of Griffipavixanthone presented the anti-cancer effect to a certain extent. In conclusion, it was suggested that Griffipavixanthone inhibit autophagy with the potential to be developed into a clinical anti-cancer agent. Griffipavixanthone sensitized He La cells to nutrient stress-induced cell death through inhibiting the autophagy flux and the level of calcium in the cytoplasm.