A metabolic investigation of anticancer effect of G. glabra root extract on nasopharyngeal carcinoma cell line, C666-1.

Although a majority of nasopharyngeal carcinoma (NPC) are undifferentiated and strongly radiosensitive, many NPC patients still have troubles in recurrence. Traditional Chinese medicine (TCM) is considered as potential therapeutic drugs in NPC. However, the effect of Glycyrrhiza glabra on NPC is limited. The present study shows the decreased proliferation and high apoptosis in G. glabra root extract-treated C666-1 cells, indicating the anti-cancerous function of G. glabra in NPC. Then GC/MS-based metabolomics is employed to characterize variation of metabolomes in response to G. glabra root extract treatment. Metabolic category elaborates the higher percentage of down-regulated amino acids and lipids after G. glabra treatment. Moreover, ICA and pathway enrichment analysis further observe that glycine, serine and threonine metabolism, fatty acid biosynthesis, alanine, aspartate and glutamate metabolism, and cysteine and methionine metabolism are four important amino acid and lipid metabolisms that likely contribute to the anti-cancer effect of G. glabra in NPC. These pathways point out the seven metabolite biomarkers, glutathione, glutamine, L-alanine, glycine, L-serine, tetradecanoic acid and stearic acid. Taken together, these findings provide potential clues that anti-cancer mechanisms of G. glabra root extract are linked to the metabolic strategies and emphasize the significance of metabolic strategies against NPC.