Influence of 6-shogaol potentiated on 5-fluorouracil treatment of liver cancer by promoting apoptosis and cell cycle arrest by regulating AKT/mTOR/MRP1 signalling

Currently, chemoresistance seriously attenuates the curative outcome of liver cancer. The purpose of our work was to investigate the influence of 6-shogaol on the inhibition of 5-fluorouracil (5-FU) in liver cancer. The cell viability of cancer cells was determined by MTT assay. Liver cancer cell apoptosis and the cell cycle were examined utilizing flow cytometry. Moreover, qRT–PCR and western blotting was used to analyse the mRNA and protein expression levels, respectively. Immunohistochemistry assays were used to examine multidrug resistance protein 1 (MRP1) expression in tumour tissues. In liver cancer cells, we found that 6-shogaol-5-FU combination treatment inhibited cell viability, facilitated G0/G1 cell cycle arrest, and accelerated apoptosis compared with 6-shogaol or 5-FU treatment alone. In cancer cells cotreated with 6-shogaol and 5-FU, AKT/mTOR pathway- and cell cycle-related protein expression levels were inhibited, and MRP1 expression was downregulated. AKT activation or MRP1 increase reversed the influence of combination treatment on liver cancer cell viability, apoptosis and cell cycle arrest. The inhibition of AKT activation to the anticancer effect of 6-shogaol-5-FU could be reversed by MRP1 silencing. Moreover, our results showed that 6-shogaol-5-FU combination treatment notably inhibited tumour growth in vivo. In summary, our data demonstrated that 6-shogaol contributed to the curative outcome of 5-FU in liver cancer by inhibiting the AKT/mTOR/MRP1 signalling pathway.