PI3K/Akt/mTOR-mediated bidirectional regulation of ampelopsin from Nekemias megalophylla modulates autophagy and apoptosis in cervical cancer

Nekemias megalophylla is a popular folk tea consumed by people in the Western Hubei (China) of which ampelopsin (AMP) is the main active ingredient. In this study, we investigated the effect of AMP on cervical cancer and explored its mechanism of action, focusing on apoptosis and autophagy. Firstly, we verified that AMP strongly inhibited the growth of C-33A cells and observed apoptosis and autophagy phenomenon in vivo, and found that AMP induces C-33A cell apoptosis via death receptor or mitochondrial pathways. The results also indicated that AMP-induced autophagy occurs via the PI3K/Akt/mTOR pathway. Secondly, when autophagy was inhibited, the AMP-induced apoptosis of C-33A cells was strengthened, when apoptosis was inhibited, the AMP-induced autophagy of C-33A cells was strengthened. PI3K/Akt/mTOR pathway activation enhances AMP-induced apoptosis in C-33A cells, while its inhibition strengthens AMP-induced autophagy. Finally, we confirmed that AMP inhibited cell growth and induced apoptosis and autophagy of C-33A cells in an in vivo nude mouse model of C-33A tumor xenografts. These results elucidate that AMP bidirectionally regulates apoptosis and autophagy in human cervical cancer C-33A cells by mediating the PI3K/Akt/mTOR pathway.