bigelovin and Liver-Neoplasms

Bigelovin (BigV), as traditional Chinese medicine, has been shown to inhibit the malignant progression of hepatocellular carcinoma (HCC). This study aimed to investigate whether BigV affects the development of HCC by targeting the MAPT and Fas/FasL pathway. Human HCC cell lines HepG2 and SMMC-7721 were used for this study. Cells were treated with BigV, sh-MAPT, and MAPT. The viability, migration, and apoptosis of HCC cells were detected by CCK-8, Transwell, and flow cytometry assays, respectively. Immunofluorescence and immunoprecipitation were used to verify the relationship between MAPT and Fas. Subcutaneous xenograft tumor and tail vein-injected lung metastases mouse models were constructed for histological observation. Hematoxylin-eosin staining was used to assess lung metastases in HCC. Western blotting was used to measure the expression of migration, apoptosis, and epithelial-mesenchymal transition (EMT) marker proteins, as well as Fas/FasL pathway-related proteins. BigV treatment inhibited the proliferation, migration, and EMT of HCC cells, whereas enhanced cell apoptosis. Moreover, BigV downregulated MAPT expression. The negative effects of sh-MAPT on HCC cell proliferation, migration, and EMT were enhanced by BigV treatment. Conversely, BigV addition attenuated the positive effects of MAPT overexpression on the malignant progression of HCC. In vivo experiments showed that BigV and/or sh-MAPT reduced tumor growth and lung metastasis while promoting tumor cell apoptosis. Furthermore, MAPT could act with Fas and inhibit its expression. sh-MAPT upregulated the expression of Fas/FasL pathway-associated proteins, which were enhanced by BigV administration. BigV suppressed the malignant progression of HCC via activating the MAPT-mediated Fas/FasL pathway.

Topics: Animals; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Movement; Cell Proliferation; Epithelial-Mesenchymal Transition; Gene Expression Regulation, Neoplastic; Humans; Liver Neoplasms; Lung Neoplasms; Mice

Bigelovin (BigV) is a sesquiterpene lactone, isolated from Inula helianthus aquatica, which has been reported to induce apoptosis and show anti-inflammatory and anti-angiogenic activities. Nevertheless, the effects of BigV on liver cancer and the underlying mechanisms have not been investigated. In the study, we found that BigV exhibited potential anti-tumor activities against human liver cancer in vitro and in vivo. BigV reduced the cell proliferation and colony formation. BigV induced apoptosis through improving the cleavage of Caspase-3 and poly (ADP-ribose) polymerase 1 (PARP-1). The process was along with the activation of autophagy, as proved by the enhanced accumulation of autophagosomes, the microtubule-associated light chain 3B-II (LC3B-II) and Beclin-1, and p62 decrease. Further, the autophagy blockage markedly sensitized BigV-induced cell death, indicating the cytoprotective function of autophagy in liver cancer cell lines. In addition, BigV treatment inactivated the pathway of protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K). Of note, BigV-induced cell death was abolished by over-expressing the phosphorylation of mTOR. Intriguingly, the induction of apoptosis and autophagy were eliminated by the pretreatment of reactive oxygen species (ROS) scavenger N-acetyl-l-cysteine (NAC), suggesting that ROS played an important role in the regulation of BigV-induced cell death. Finally, in vivo studies demonstrated that BigV significantly suppressed the growth of HepG2 cancer xenograft tumors through the activation of apoptosis and autophagy in a dose-dependent manner with low systemic toxicity. In conclusion, the results revealed that BigV had significant antitumor effects against human liver cancer and it may potentially be used as a novel antitumor agent for the prevention of liver cancer.

Topics: Animals; Apoptosis; Autophagosomes; Autophagy; Cell Line, Tumor; Cell Proliferation; Humans; Lactones; Liver Neoplasms; Male; Mice, Inbred BALB C; Mice, Nude; Reactive Oxygen Species; Sesquiterpenes; Signal Transduction; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays