Sun Xinfeng, Zhong Xin, Ma Wenfeng, Feng Wenxing, Huang Qi, Ma Mengqing, Lv Minling, Hu Rui, Han Zhiyi, Li Jing, Zhou Xiaozhou
Department of Liver Disease, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, Guangdong 518033, P.R. China.
Department of Liver Disease, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, Guangdong 518033, P.R. China.
Exp Ther Med. 2022 May 20;24(1):456. doi: 10.3892/etm.2022.11383. eCollection 2022 Jul.
Liver cancer is a highly lethal malignancy. Despite considerable efforts made in recent years, the prognosis of patients with liver cancer remains poor. (known as Ezhu in Chinese) is widely prescribed in traditional Chinese medicine. Germacrone (GM) is a sesquiterpene constituent derived from the essential oil of Ezhu, and exerts anti-carcinogenic effects by inducing apoptosis in various cancer cells. The present study investigated the potential mechanism of GM in HepG2 cells. Cell Counting Kit-8, colony-formation and lactate dehydrogenase-release assays, as well as cell death assays using flow cytometry, were performed to evaluate HepG2 cell proliferation following GM treatment. HepG2 cells were transfected with caspase-3 small interfering RNA and then treated with GM. Caspase-3 expression levels were determined by reverse transcription-quantitative PCR and western blotting. The present study showed that GM inhibited the growth of HepG2 cells and induced the proteolytic cleavage of caspase 3, with concomitant cleavage of gasdermin E (GSDME), by markedly increasing the production of reactive oxygen species (ROS). This led to caspase 3-dependent cleavage of GSDME, thereby promoting pyroptosis in HepG2 cells. However, these changes were rescued by ROS scavengers, such as N-acetylcysteine. Furthermore, GM inhibited tumor growth by promoting the cleavage of caspase 3 and GSDME in HepG2 cell xenograft models. These results indicated that GM induced GSDME-dependent pyroptosis through caspase 3 activation, at least in part, by damaging the mitochondria and enhancing ROS production, thereby supporting the possible development of GM as a candidate for the prevention and treatment of liver cancer.
肝癌是一种高度致命的恶性肿瘤。尽管近年来付出了巨大努力，但肝癌患者的预后仍然很差。莪术（中文名为莪术）在传统中医中被广泛应用。吉马酮（GM）是从莪术精油中提取的一种倍半萜成分，通过诱导各种癌细胞凋亡发挥抗癌作用。本研究探讨了GM在肝癌细胞系HepG2中的潜在作用机制。采用细胞计数试剂盒-8、集落形成和乳酸脱氢酶释放试验，以及使用流式细胞术进行细胞死亡试验，以评估GM处理后HepG2细胞的增殖情况。将caspase-3小干扰RNA转染到HepG2细胞中，然后用GM处理。通过逆转录定量PCR和蛋白质印迹法测定caspase-3的表达水平。本研究表明，GM通过显著增加活性氧（ROS）的产生，抑制HepG2细胞的生长，并诱导caspase 3的蛋白水解切割，同时伴随gasdermin E（GSDME）的切割。这导致GSDME依赖于caspase 3的切割，从而促进HepG2细胞的焦亡。然而，这些变化可被ROS清除剂如N-乙酰半胱氨酸挽救。此外，在HepG2细胞异种移植模型中，GM通过促进caspase 3和GSDME的切割来抑制肿瘤生长。这些结果表明，GM至少部分通过损伤线粒体和增强ROS产生，激活caspase 3诱导GSDME依赖的焦亡，从而支持GM作为肝癌预防和治疗候选药物的潜在开发。
