Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry serum protein profiling to identify nasopharyngeal carcinoma.
BACKGROUND
Diagnosis of nasopharyngeal carcinoma (NPC) at an early disease stage is important for successful treatment and improving the outcome of patients. The use of serum protein profiles and a classification tree algorithm were explored to distinguish NPC from noncancer.


METHODS
Serum samples were applied to metal affinity protein chips to generate mass spectra by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Protein peak identification and clustering were performed using the Biomarker Wizard software. Proteomic spectra of serum samples from 50 NPC patients and 54 noncancer controls were used as a training set and a classification tree with 6 distinct protein masses was generated by using Biomarker Pattern software. The validity of the classification tree was then challenged with a blind test set including another 20 NPC patients and 25 noncancer controls.


RESULTS
The software identified an average of 93 mass peaks/spectrum and 6 of the identified peaks were used to construct the classification tree. The classification tree correctly determined 83% (123 of 149) of the test samples with 83% (58 of 70) of the NPC samples and 82% (65 of 79) of the noncancer samples. In a combination of the serum protein profiles with Epstein-Barr (EBV) nuclear antigen 1 (EBNA1 IgA) test, the diagnostic sensitivity and specificity were increased to 99% and 96%, respectively.


CONCLUSIONS
The results suggest that SELDI-TOF-MS serum protein profiles could discriminate NPC from noncancer. The combination of serum protein profiles with an EBV antibody serology test could further improve the accuracy of NPC screening.
Ho
David Wing Yuen
DW
Department of Surgery, University of Hong Kong, Pokfulam, Hong Kong, China.
Yang
Zhen Fan
ZF
Wong
Birgitta Yee-Hang
BY
Kwong
Dora Lai-Wan
DL
Sham
Jonathan Shun-Tong
JS
Wei
William Ignace
WI
Yuen
Anthony Po Wing
AP
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015415:Biomarkers / Q000097:blood*; D003663:Decision Trees; D005260:Female; D006801:Humans; D008297:Male; D046208:Microchip Analytical Procedures; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000097:blood / Q000145:classification* / Q000175:diagnosis*; D009363:Neoplasm Proteins / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013499:Surface Properties
D015415:Biomarkers; D009363:Neoplasm Proteins