Department of Respiratory and Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, China.
Thorac Cancer. 2021 Apr;12(8):1219-1230. doi: 10.1111/1759-7714.13904. Epub 2021 Mar 3.
Emerging studies showed curcumin can inhibit glioblastoma and breast cancer cells via regulating ferroptosis. However, the role of ferroptosis in the inhibitory effect of curcumin on non-small-cell lung cancer (NSCLC) remains unclear.
Cell counting kit-8 (CCK-8) assay was used to measure the viability of A549 and H1299 cells under different conditions. Cell proliferation was examined by Ki67 immunofluorescence. The morphological changes of cells and tumor tissues were observed by optical microscope and hematoxylin and eosin (H&E) staining. Intracellular reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and iron contents were determined by corresponding assay kit. The related protein expression levels were detected by western blot and immunohistochemistry. Transmission electron microscope was used to observe ultrastructure changes of A549 and H1299 cells.
Curcumin inhibited tumor growth and cell proliferation, but promoted cell death. Characteristic changes of ferroptosis were observed in curcumin group, including iron overload, GSH depletion and lipid peroxidation. Meanwhile, the protein level of ACSL4 was higher and the levels of SLC7A11 and GPX4 were lower in curcumin group than that in control group. Incubation of ferroptosis inhibitors ferrostatin-1 (Fer-1) or knockdown of iron-responsive element-binding protein 2 (IREB2) notably weakened curcumin-induced anti-tumor effect and ferroptosis in A549 and H1299 cells. Further investigation suggested that curcumin induced mitochondrial membrane rupture and mitochondrial cristae decrease, increased autolysosome, increased the level of Beclin1 and LC3, and decreased the level of P62. Curcumin-induced autophagy and subsequent ferroptosis were both alleviated with autophagy inhibitor chloroquine (CQ) or siBeclin1.
Curcumin induced ferroptosis via activating autophagy in NSCLC, which enhanced the therapeutic effect of NSCLC.
新的研究表明姜黄素可以通过调节铁死亡来抑制神经胶质瘤和乳腺癌细胞。然而，铁死亡在姜黄素抑制非小细胞肺癌（NSCLC）中的作用尚不清楚。
用细胞计数试剂盒-8（CCK-8）检测不同条件下 A549 和 H1299 细胞的活力。用 Ki67 免疫荧光法检测细胞增殖。用光学显微镜和苏木精和伊红（H&E）染色观察细胞和肿瘤组织的形态变化。用相应的试剂盒测定细胞内活性氧（ROS）、丙二醛（MDA）、超氧化物歧化酶（SOD）、谷胱甘肽（GSH）和铁含量。用 Western blot 和免疫组化检测相关蛋白表达水平。用透射电子显微镜观察 A549 和 H1299 细胞的超微结构变化。
姜黄素抑制肿瘤生长和细胞增殖，但促进细胞死亡。在姜黄素组观察到特征性的铁死亡变化，包括铁过载、GSH 耗竭和脂质过氧化。同时，姜黄素组 ACSL4 蛋白水平较高，SLC7A11 和 GPX4 水平较低。铁死亡抑制剂 ferrostatin-1（Fer-1）孵育或铁反应元件结合蛋白 2（IREB2）敲低显著减弱了 A549 和 H1299 细胞中姜黄素诱导的抗肿瘤作用和铁死亡。进一步研究表明，姜黄素诱导线粒体膜破裂和线粒体嵴减少，增加自噬体，增加 Beclin1 和 LC3 水平，降低 P62 水平。姜黄素诱导的自噬和随后的铁死亡都被自噬抑制剂氯喹（CQ）或 siBeclin1 减轻。
姜黄素通过激活非小细胞肺癌中的自噬来诱导铁死亡，从而增强非小细胞肺癌的治疗效果。
