Harmine Hydrochloride Induces G2/M Cell Cycle Arrest and Apoptosis in SK-Hep1 Hepatocellular Carcinoma Cells by Regulating Mitogen-Activated Protein Kinases and the PI3K/AKT Pathway

Liver cancer is a globally common form of cancer. Thus, novel drugs derived from natural products are needed to reduce the side effects of chemotherapy. The present study aimed to analyze the anticancer properties and effects of harmine hydrochloride (HMH), a water-soluble metabolite of harmine that can be easily absorbed into tissues, in treating liver cancer cells. HMH dose-dependently inhibited cell growth, migration, invasion, and colony formation in SK-Hep1 cells. It also induced G2/M arrest by reducing the expression of p-cdc2, cyclin B1, and Rb (G2/M phase regulatory proteins) in a dose-dependent manner. HMH treatment reduced the expression of caspase-9, caspase-3, PARP, and Bcl-2 and increased the expression of Bax (a proapoptotic protein). Moreover, it increased the production of reactive oxygen species and decreased the intracellular uptake of rhodamine 123 due to mitochondrial dysfunction because of oxidative stress. HMH treatment also upregulated the phosphorylation of JNK, p38, and FOXO3a in SK-Hep1 cells and downregulated the PI3K/AKT signaling pathway. Our findings suggest that HMH may activate the compounds responsible for anticancer effects in hepatocellular carcinoma cells.