title: Three aromatic amino acids in gastric juice as potential biomarkers for gastric malignancies.
abstract: For screening early-stage gastric malignancies, the existing serum biomarkers have limited sensitivity and specificity. Gastric juice biomarkers are scarce and require further investigation. We divided this study on searching potential biomarkers into four parts: (1) detection of differential fluorescence spectrum and peaks in the gastric juice from patients using fluorescence spectroscopy and HPLC, (2) identification and validation of differential peaks using LC/MS and NMR, (3) quantification of potential biomarkers, and (4) establishment of diagnostic detection. The fluorescence intensity (FI), tyrosine, phenylalanine, tryptophan and total protein content were significantly higher in the gastric juice of patients with gastric malignancies (all P<0.01). With all P<0.001, the areas under the receiver operating characteristic curves of the biomarkers were tyrosine, 0.838; phenylalanine, 0.856; and tryptophan, 0.816. At a specificity of 79.4%, the sensitivity for gastric malignancy detection with phenylalanine was 87.9% only. Aromatic amino acids in gastric juices could be used as potential diagnostic biomarkers to screen gastric malignancies. It is a less-invasive and economical method compared to gastric biopsy.
authors.affiliation: Department of Gastroenterology, Peking University Third Hospital, Haidian District, Beijing, China. dengkai11111@163.com
authors.forename: Kai
authors.initials: K
authors.lastname: Deng
authors.forename: Sanren
authors.initials: S
authors.lastname: Lin
authors.forename: Liya
authors.initials: L
authors.lastname: Zhou
authors.forename: Qiuming
authors.initials: Q
authors.lastname: Geng
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.forename: Renhua
authors.initials: R
authors.lastname: Na
mesh_terms: D024322:Amino Acids, Aromatic / Q000032:analysis*; D014408:Biomarkers, Tumor / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005750:Gastric Juice / Q000737:chemistry*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D010649:Phenylalanine / Q000032:analysis; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013274:Stomach Neoplasms / Q000175:diagnosis*; D014364:Tryptophan / Q000032:analysis; D014443:Tyrosine / Q000032:analysis
chemical_list: D024322:Amino Acids, Aromatic; D014408:Biomarkers, Tumor; D014443:Tyrosine; D010649:Phenylalanine; D014364:Tryptophan