title: Plasma free amino acid profiling of esophageal cancer using high-performance liquid chromatography spectroscopy.
abstract: OBJECTIVE
  To perform plasma free amino acid (PFAA) profiling of esophageal squamous cell carcinoma (ESCC) patients at different pathological stages and healthy subjects.
  
  
  METHODS
  Plasma samples from ESCC patients (n = 51) and healthy control adults (n = 60) were analyzed by high-performance liquid chromatography (HPLC). The ESCC patients included moderate/poorly-differentiation (n = 24), lymph node metastasis (n = 17) and clinical stage > Ib2 (n = 36). Partial least squares discriminant analysis was performed to demonstrate that the PFAA metabolic patterns enabled discrimination between ESCC patients and controls, and the Student t test was applied to assess significant differences in PFAA concentrations between the two groups.
  
  
  RESULTS
  There were significant differences in the PFAA profiles between controls and ESCC patients. Compared with healthy controls, the levels of Asp, Glu, Gly, His, Thr, Tau, Ala, Met, Ile, Leu, and Phe were decreased in ESCC patients, but Cys was increased. There exists a strong correlation between PFAA profiles and clinicopathological characteristics in ESCC patients. The levels of many PFAAs (i.e., Glu, Asp, Ser, Gly, Tau, Ala, Tyr, Val, Ile, and Leu) were related to pathological grading, lymph node metastasis, and ESCC clinical stage. Very good discrimination between ESCC patients and control subjects was achieved by multivariate modeling of plasma profiles.
  
  
  CONCLUSIONS
  HPLC-based plasma profiling analysis was shown to be an effective approach to differentiate between ESCC patients and controls. PFAA profiles may have potential value for screening or diagnosing ESCC.
authors.affiliation: Hong Ma, Hai-Ping Zhang, Ilyar Sheyhidin, Department of Thoracic Surgery, The First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uyghur Autonomous Region, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.affiliation: Hong Ma, Hai-Ping Zhang, Ilyar Sheyhidin, Department of Thoracic Surgery, The First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uyghur Autonomous Region, China.
authors.forename: Ayshamgul
authors.initials: A
authors.lastname: Hasim
authors.affiliation: Hong Ma, Hai-Ping Zhang, Ilyar Sheyhidin, Department of Thoracic Surgery, The First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uyghur Autonomous Region, China.
authors.forename: Batur
authors.initials: B
authors.lastname: Mamtimin
authors.affiliation: Hong Ma, Hai-Ping Zhang, Ilyar Sheyhidin, Department of Thoracic Surgery, The First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uyghur Autonomous Region, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Kong
authors.affiliation: Hong Ma, Hai-Ping Zhang, Ilyar Sheyhidin, Department of Thoracic Surgery, The First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uyghur Autonomous Region, China.
authors.forename: Hai-Ping
authors.initials: HP
authors.lastname: Zhang
authors.affiliation: Hong Ma, Hai-Ping Zhang, Ilyar Sheyhidin, Department of Thoracic Surgery, The First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uyghur Autonomous Region, China.
authors.forename: Ilyar
authors.initials: I
authors.lastname: Sheyhidin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000473:pathology; D016022:Case-Control Studies; D002454:Cell Differentiation; D002851:Chromatography, High Pressure Liquid; D004938:Esophageal Neoplasms / Q000097:blood* / Q000473:pathology; D000077277:Esophageal Squamous Cell Carcinoma; D005260:Female; D006801:Humans; D016018:Least-Squares Analysis; D008207:Lymphatic Metastasis; D008297:Male; D055432:Metabolomics / Q000379:methods*; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000596:Amino Acids; D014408:Biomarkers, Tumor
keywords: Amino acids; Esophageal squamous cell cancer; High-performance liquid chromatography; Metabolomics; Plasma