Zheng Fang, Wang Yeshu, Zhang Qunfang, Chen Qiuyuan, Liang Chun-Ling, Liu Huazhen, Qiu Feifei, Chen Yuchao, Huang Haiding, Lu Weihui, Dai Zhenhua
Section of Immunology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.
Joint Immunology Program, Guangdong Provincial Academy of Chinese Medical Sciences, Guangzhou, Guangdong, China.
Front Pharmacol. 2023 Apr 4;14:1145407. doi: 10.3389/fphar.2023.1145407. eCollection 2023.
Ferroptosis is a new form of regulated cell death characterized by the accumulation of iron-dependent lipid peroxides and membrane damages. Recent studies have identified an important role for cancer cell ferroptosis in antitumor therapy. On the other hand, polyphyllin I (PPI) has been reported to exert antitumor effects on some types of cancers. However, it remains unknown whether or not PPI regulates cancer cell ferroptosis. Two types of human gastric cancer cells (AGS and MKN-45) were used to establish tumor xenograft models in nude mice that were treated with polyphyllin I (PPI) to observe tumor growth, while cells also were cultured for studies. Ferroptosis, based on the intracellular ROS/lipid ROS production and accumulation of ferrous ions, was detected using a fluorescence microscope and flow cytometer, while the expression of NRF2/FTH1 was measured using Western blotting assays. Here we found that PPI inhibited the gastric cancer growth and while increasing the intracellular reactive oxygen species (ROS)/lipid peroxides and ferrous ions in the gastric cancer cells. PPI also decreased the levels of nuclear factor erythroid 2-related factor 2 (NRF2) and ferritin heavy chain 1 (FTH1) in gastric cancer cells . Moreover, liproxstain-1, an inhibitor of cell ferroptosis, mostly reversed the cell ferroptosis and tumor growth arrest induced by PPI. Finally, the effects of PPI on cancer cell ferroptosis were diminished by the overexpression of NRF2. For the first time, our results have demonstrated that PPI exerts its antitumor activity on the gastric cancer by, at least partially, inducing cancer cell ferroptosis regulating NRF2/FTH1 pathway. These findings may be implicated for clinical replacement therapy of the gastric cancer.
铁死亡是一种新的程序性细胞死亡形式,其特征是铁依赖性脂质过氧化物的积累和膜损伤。最近的研究已经确定癌细胞铁死亡在抗肿瘤治疗中具有重要作用。另一方面,据报道,重楼皂苷I(PPI)对某些类型的癌症具有抗肿瘤作用。然而,PPI是否调节癌细胞铁死亡仍不清楚。使用两种人类胃癌细胞(AGS和MKN-45)在裸鼠中建立肿瘤异种移植模型,用重楼皂苷I(PPI)处理以观察肿瘤生长,同时也对细胞进行培养研究。基于细胞内活性氧/脂质活性氧的产生和亚铁离子的积累,使用荧光显微镜和流式细胞仪检测铁死亡,同时使用蛋白质免疫印迹法测量NRF2/FTH1的表达。在这里,我们发现PPI抑制胃癌生长,同时增加胃癌细胞内的活性氧(ROS)/脂质过氧化物和亚铁离子。PPI还降低了胃癌细胞中核因子红细胞2相关因子2(NRF2)和铁蛋白重链1(FTH1)的水平。此外,细胞铁死亡抑制剂liproxstain-1大多逆转了PPI诱导的细胞铁死亡和肿瘤生长停滞。最后,NRF2的过表达减弱了PPI对癌细胞铁死亡的影响。我们的结果首次证明PPI至少部分地通过诱导癌细胞铁死亡和调节NRF2/FTH1途径对胃癌发挥其抗肿瘤活性。这些发现可能对胃癌的临床替代治疗有启示。