Anti-tumor effects of Silybum marianum essential oil and 5-fluorouracil combination on Hepatocellular carcinoma cells (HepG2)

The present study evaluated the efficacy of combining 5-fluorouracil (5-FU) and Silybum marianum essential oils to suppress in vitro Hepatocellular carcinoma (HCC) growth by influencing the Wnt, NF-κB, angiogenesis, apoptosis and autophagy pathways. Silybum marianum essential oils were studied alone and in combination with 5-FU in the HepG2 cell-line. The expression of NF-κB and Wnt signaling pathway genes as well as angiogenesis-, apoptosis- and autophagy-associated genes and proteins were evaluated using Western blot and qRT-PCR techniques. Each treatment decreased the viability of HepG2 cells compared with the control group. Moreover, S. marianum essential oils from Khozestan or Isfahan (Sm-K and Sm-I) in combination with 5-FU reduced the migration and invasion of HepG2 cells. Angiogenesis-related proteins i.e. VEGF, COX-2, Bfgf and HIF-1α were significantly reduced. Apoptosis- and autophagy-related proteins i.e. caspase-8, Bax, Bcl-2, Beclin-1, LC3-I, and LC3-II were modulated by each treatment. Each treatment decreased total NF κB (p65) and phospho NF κB (p65) at protein levels. The expression levels of Wnt pathway-related genes were also decreased. Taken together, these findings revealed that S. marianum, either alone or in combination with 5-Fu, could exert anti-tumor effects via modulating autophagy, apoptosis, angiogenesis, NF κB and Wnt signaling pathways.