从红花碱提取而得的六甲氧基二氢小檗碱（6-MS），是一种天然的苯并二氮杂菁生物碱。研究表明，6-MS具有触发癌细胞凋亡的能力。然而，关于其具体作用机制仍不清楚。本研究揭示了6-MS诱导肝细胞癌细胞（HCC）细胞毒性的潜在机制，并研究了6-MS是否增强了肿瘤坏死因子相关凋亡诱导配体（TRAIL）诱导的细胞凋亡。研究发现，6-MS抑制了HCC细胞的增殖，并引发了细胞周期阻滞、DNA损伤和凋亡。机制分析表明，6-MS促进了活性氧（ROS）产生、JNK活化，并抑制了EGFR/Akt信号通路。通过N-乙酰半胱氨酸（NAC）处理，可以逆转6-MS诱导的DNA损伤和凋亡。6-MS增强的PARP裂解可以通过JNK抑制剂SP600125预处理而取消。此外，6-MS通过上调细胞表面受体DR5的表达增强了TRAIL介导的HCC细胞凋亡。NAC预处理减弱了6-MS促进的DR5蛋白表达，并减轻了联合处理引起的细胞活力减少、caspase-8、caspase-9和PARP的裂解。总的来说，我们的研究结果表明，6-MS通过调节ROS生成、EGFR/Akt信号和JNK活化在HCC细胞中发挥细胞毒性作用。6-MS通过ROS生成上调DR5表达，增强了TRAIL诱导的细胞凋亡。6-MS与TRAIL的联合应用可能是一种有前景的策略，值得进一步研究。 © 2023年作者，独家许可给斯普林格科学+ 商业传媒有限公司，斯普林格自然部分。

6-methoxydihydrosanguinarine (6-MS), a natural benzophenanthridine alkaloid extracted from Macleaya cordata (Willd.) R. Br, has shown to trigger apoptotic cell death in cancer cells. However, the exact mechanisms involved have not yet been clarified. The current study reveals the underlying mechanisms of 6-MS-induced cytotoxicity in hepatocellular carcinoma (HCC) cells and investigates whether 6-MS sensitizes TNF-related apoptosis inducing ligand (TRAIL)-induced apoptosis. 6-MS was shown to suppress cell proliferation and trigger cell cycle arrest, DNA damage, and apoptosis in HCC cells. Mechanisms analysis indicated that 6-MS promoted reactive oxygen species (ROS) generation, JNK activation, and inhibits EGFR/Akt signaling pathway. DNA damage and apoptosis induced by 6-MS were reversed following N-acetyl-l-cysteine (NAC) treatment. The enhancement of PARP cleavage caused by 6-MS was abrogated by pretreatment with JNK inhibitor SP600125. Furthermore, 6-MS enhanced TRAIL-mediated HCC cells apoptosis by upregulating the cell surface receptor DR5 expression. Pretreatment with NAC attenuated 6-MS-upregulated DR5 protein expression and alleviated cotreatment-induced viability reduction, cleavage of caspase-8, caspase-9, and PARP. Overall, our results suggest that 6-MS exerts cytotoxicity by modulating ROS generation, EGFR/Akt signaling, and JNK activation in HCC cells. 6-MS potentiates TRAIL-induced apoptosis through upregulation of DR5 via ROS generation. The combination of 6-MS with TRAIL may be a promising strategy and warrants further investigation.© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.