Lappaconitine Sulfate Inhibits Proliferation and Induces Apoptosis in Human Hepatocellular Carcinoma HepG2 Cells through the Reactive Oxygen Species-Dependent Mitochondrial Pathway.

Background: Hepatocellular carcinoma (HCC) is the third leading cause of tumor-related deaths in the word. Lappaconitine (LA), a diterpenoid alkaloid, exerts antitumor activities. However, the effects and mechanisms of LA sulfate (LS) on HCC remain unclear. This study evaluated the activities and explored the underlying mechanisms of LS in HCC cell line HepG2 cells.

Materials And Methods: The cell viability and proliferation were evaluated using the Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assay, respectively. The cell cycle distribution was detected by propidium iodide (PI) staining assay. The apoptosis was detected by Annexin -V-fluorescein isothiocyanate (FITC)/PI double staining assay. The cell cycle arrest and apoptosis-related proteins were estimated by western blot analysis. The mitochondrial membrane potential (MMP) was -determined through the 5, 5', 6, 6'-tetrachloro-1, 1', 3, 3'-tetraethylbenzimi-dazolyl carbocyanine iodide (JC-1) staining assay. The reactive oxygen species (ROS) was monitored by 20-70-dichlorofluorescein diacetate (DCFH-DA) staining assay. In vivo antitumor activities were investigated by HepG2 xenograft model.

Results: Our results showed that LS significantly -inhibited the viability and proliferation of HepG2 cells. LS triggered G0/G1 cell cycle arrest, apoptosis and caspase activation. Furthermore, LS induced MMP loss and ROS accumulation. Additionally, LS suppressed the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/glycogen synthase kinase 3β (GSK3β) signaling pathway. An in vivo assay showed that LS exhibited a pronounced antitumor effect in nude mice bearing HepG2 xenografts.

Conclusions: Our results demonstrated that LS is a promising therapeutic agent for HCC directed -toward the proliferation inhibition and the induction of apoptosis.