AUTHOR=Zhang Chao , Yang Hong-Ying , Gao Long , Bai Ming-Zhen , Fu Wen-Kang , Huang Chong-Fei , Mi Ning-Ning , Ma Hai-Dong , Lu Ya-Wen , Jiang Ning-Zu , Tian Liang , Cai Teng , Lin Yan-Yan , Zheng Xing-Xing , Gao Kun , Chen Jian-Jun , Meng Wen-Bo 

TITLE=Lanatoside C decelerates proliferation and induces apoptosis through inhibition of STAT3 and ROS-mediated mitochondrial membrane potential transformation in cholangiocarcinoma

JOURNAL=Frontiers in Pharmacology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2023.1098915

DOI=10.3389/fphar.2023.1098915

ISSN=1663-9812

ABSTRACT=The incidence of Cholangiocarcinoma(CCA) has increased worldwide in recent years. Given the poor efficacy of the current approach for CCA, new therapeutic agents are warranted to improve the prognosis of this patient population. In this study, we extracted five cardiac glycosides from natural plants: Lanatoside A (1), digoxin (2), Lanatoside C(3), gitoxin (4), and Lanatoside B (5). Drug experiments were performed to assess the effect of these five extracts on cholangiocarcinoma cells and select the drug with the best efficacy. Lanatoside C (Lan C) was selected as the most potent natural extract for subsequent experiments. We explored the potential mechanism underlying the anticancer activity of Lan C on cholangiocarcinoma cells by flow cytometry, western blot, immunofluorescence, bioinformatic analysis, network pharmacology and in vivo experiments. We observed that Lan C time-dependently inhibited the growth and induced apoptosis of HuCCT-1 and TFK-1 cholangiocarcinoma cells. Our data suggest that Lan C increased reactive oxygen species(ROS) content in cholangiocarcinoma cells, decreased the mitochondrial membrane potential(MMP) and resulted in apoptosis. Besides, Lan C downregulated the protein expression of STAT3, leading to decreased expression of Bcl-2 and Bcl-xl, increased expression of Bax, activation of caspase-3, and initiation of apoptosis. N-acetyl- l-cysteine (NAC) pretreatment reversed the effect of Lan C. In vivo, we found that Lan C inhibited the growth of cholangiocarcinoma xenografts without toxic effects on normal cells. Tumor immunohistochemistry showed that treating human cholangiocarcinoma transplantation tumor nude mice with Lan C resulted in decreased STAT3 expression and increased caspase-9 and caspase-3 expression in tumors, consistent with the results of in vitro experiments. In summary, Our results substantiates that cardiac glycosides have strong anti-CCA effects. The biological activity of Lan C provides a new anticancer candidate for the treatment of cholangiocarcinoma.