Abstract:Objective:To investigate metabolic changes of amino acid and lipids in tissues and plasma of gastric cancer(GC),and to reveal the metabolic link between tissues and plasma of gastric cancer. Methods:The levels of amino acid and lipids were measured in 20 chronic superficial gastritis (CSG) tissue samples,17 GC tissue samples,15 CSG plasma samples,15 GC plasma samples and 15 postoperative GC plasma samples by means of gas chromatography-time of flight mass spectrometry (GC/TOFMS)-based technique,and t-test was employed to analyze data. Results:The levels of amino acids in GC tissue were generally elevated or equal to CSG tissue,especially cysteine(P = 0.007),and 2-aminoadipic acid (P = 0.045)and glutamine(P = 0.047),and the levels of amino acid in GC plasma were generally lower than that in CSG plasma,especially cysteine(P = 0.029),serine(P = 0.013)and glycine(P = 0.043). Compared to CSG tissue,the levels of 3-hydroxybutyric acid (P = 0.003),hexadecenoic acid(P = 0.030) and heptanoic acid(P = 0.047) were up-regulated,while cholesterol (P = 0.003)was down-regulated in GC tissue. The levels of amino acid and lipids metabolites in postoperative GC plasma were restored towards CSG plasma. Conclusion:The study demonstrates that the abnormal metabolism of amino acid and lipids in GC tissue affects the metabolism of amino acid and lipids in plasma,and suggestes GC/TOF-based techniques is a suitable tool for gastric cancer metabolism investigations.