Tenuigenin inhibits the cell growth and proliferation by regulating the cell cycle and central carbon metabolism in cancer pathway in hepatocellular carcinoma

Tenuigenin (TEN) is a natural extract from Polygala tenuifolia root, that has been reported to show the effects of anti-insomnia, anti- amnesia, neuroprotective, and anti-inflammatory effects. This study aimed to investigate the anti-hepatocellular carcinoma (HCC) effects of TEN and explore the underlying molecular mechanisms. Hep3B and HCCLM3 cells were selected to evaluate the anti-tumor effects of TEN in vitro. RNA-sequence (RNA-seq) was used to identify possible molecular targets and pathways. LC-MS was used to evaluate the effect of TEN treatment on the primary metabolites of HCCLM3 cells. Tumor xenograft was performed in nude mice to examine the anti-tumor properties of TEN in vivo. The results showed that TEN significantly inhibited the tumorigenicity of HCC cells, including inhibiting the proliferation and migration and also induce apoptosis of cells in vitro. RNA-seq result showed that 2325 genes are upregulated and 3725 genes are downregulated in TEN group compared with control group, which were highly enriched in cell cycle pathway. In addition, metabolomics analysis revealed that TEN interfered with the central carbon metabolism in cancer metabolism pathway of HCC cells by significantly inhibiting the synthesis of s-malate, succinate, D-(-)-salicin metabolites. Furthermore, subcutaneous tumor formation experiments revealed that TEN significantly suppressed the tumor growth. Immunohistochemical analysis further revealed that treatment of TEN significantly decreased the expression of the proliferation marker Ki67. In conclusion, our findings indicated that TEN could inhibit cell proliferation and by regulating central carbon metabolism in cancer pathway, and has the potential to be a candidate anti-cancer drug for the treatment of HCC.