Effects of diphyllin as a novel V-ATPase inhibitor on TE-1 and ECA-109 cells.

Diphyllin is a natural component of traditional Chinese medicine, which effectively inhibits V-ATPase activity and affects the progression of cancer. However, few studies have been conducted on esophageal cancer, and the mechanisms remain to be elucidated. The present study revealedthat diphyllin inhibited proliferation and induced S arrest in esophageal cancer cell lines TE-1 and ECA-109. Further experiments revealed that diphyllin inhibited V-ATPase activity and decreased the mRNA expression of mammalian target of rapamycin complex 1 (mTORC1), hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF). The present study also revealed that diphyllin inhibited proliferation and reduced the formation of new blood vessels. Diphyllin inhibited blood metastasis by regulating the mTORC1/HIF-1α-/VEGF pathway, therefore it could be considered as a new V-ATPase inhibitor to treat esophageal cancer.