Glucose and glutamine metabolism in oral squamous cell carcinoma: insight from a quantitative metabolomic approach.

OBJECTIVE: To characterize the metabolic system of oral squamous cell carcinoma (OSCC) by metabolome analysis. STUDY DESIGN: The metabolome profiles, including the Embden-Meyerhof-Parnas pathway (EMPP), the pentose phosphate pathway, the tricarboxylic acid cycle (TCAC), and amino acids, were obtained from OSCC and its surrounding normal tissues (32 patients) using capillary electrophoresis and a time-of-flight mass spectrometer. RESULTS: Enhancement of glucose consumption and lactate production (Warburg effect) was observed in OSCC tissues. The decrease of glucose along with the decrease of the downstream intermediates in the EMPP suggests that incorporated glucose is mainly consumed for biosynthesis. Glutamine consumption with the increase of the intermediates in the last half of the TCAC suggests the involvement of glutaminolysis, in which glutamine is converted to lactate via the last half of the TCAC. CONCLUSIONS: It is suggested that OSCC tissues show the Warburg effect, which stems from the combined enhancement of glucose consumption and glutaminolysis.