Dihydroergotamine mesylate enhances the anti-tumor effect of sorafenib in liver cancer cells

Liver cancer is the most common and frequentlyoccurring cancer. In addition to radiotherapy, chemotherapy and surgery are recommended as part of liver cancer treatment. The efficacy of sorafenib and sorafenib-based combination treatment against tumors has been verified. Although, clinical trials have revealed that some individuals are not sensitive to sorafenib therapy, and current therapeutic approaches are ineffective. Consequently, it is urgent to explore effective drug combinations and innovative techniques for increasing the effectiveness of sorafenib in the curing of liver tumor. Herein, we show that dihydroergotamine mesylate (DHE), an anti-migraine agent, could effectively suppress liver cancer cells proliferation by inhibiting STAT3 activation. However, DHE can enhance the protein stability of Mcl-1 by activating ERK, making DHE less effective in apoptosis induction. Specifically, DHE enhances the effects of sorafenib on liver cancer cells, such as decreased viability and increased apoptosis. Furthermore, the mixture of sorafenib and DHE could enhance DHE-triggered STAT3 suppression and inhibit DHE-mediated ERK-Mcl-1 pathway activation. In vivo, the combination of sorafenib with DHE produced a substantial synergy in suppressing tumour growth and causing apoptosis, ERK inhibition and Mcl-1 degradation. These findings suggest that DHE can effectively inhibit cell proliferation and enhance sorafenib anti-cancer activity in liver cancer cells. The current study provides some new insights that DHE asa novel anti-liver cancer therapeutic agent has been shown to improve treatment outcomes of sorafenib, which might be helpful in order to advance sorafenib in liver cancer therapeutics.