Identification of potential serum markers for nasopharyngeal carcinoma from a xenografted mouse model using Cy-dye labeling combined with three-dimensional fractionation.
Nasopharyngeal carcinoma (NPC), one of the most common cancers in Southeast Asia, is commonly diagnosed late due to its deep location and vague symptoms. To identify biomarkers for improving NPC diagnosis, we established a proteomic platform for detecting aberrant serum proteins in nude mice bearing NPC xenografts. We first removed the three most abundant proteins from serum samples of tumor-bearing and control mice, and then labeled the samples with different fluorescent cyanine (Cy) dyes. The labeled serum proteins were then mixed equally and fractionated with ion-exchange chromatography followed by SDS-PAGE. Differentially expressed proteins were identified by in-gel tryptic digestion and MALDI-TOF MS. We identified peroxiredoxin 2 (Prx-II) and carbonic anhydrase 2 (CA-II) as being elevated in the xenograft mouse model compared to controls. Western blot analysis confirmed up-regulation of Prx-II and CA-II in plasma from five NPC patients, and ELISA showed that plasma Prx-II levels were significantly higher in NPC patients (n = 84) versus healthy controls (n = 90) (3.03 +/- 4.47 versus 1.90 +/- 2.74 microg/mL, p = 0.047). In conclusion, Cy dye labeling combined with three-dimensional fractionation is a feasible strategy for identifying differentially expressed serum proteins in an NPC xenograft model, and Prx-II may represent a potential NPC biomarker.
Wu
Chih-Ching
CC
Proteomics Core Laboratory, Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
Peng
Pei-Hua
PH
Chang
Ya-Ting
YT
Huang
Yu-Shan
YS
Chang
Kai-Ping
KP
Hao
Sheng-Po
SP
Tsang
Ngan-Ming
NM
Yeh
Chau-Ting
CT
Chang
Yu-Sun
YS
Yu
Jau-Song
JS
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D014408:Biomarkers, Tumor / Q000097:blood* / Q000302:isolation & purification; D002232:Carbocyanines; D024402:Carbonic Anhydrase II / Q000097:blood*; D002648:Child; D004195:Disease Models, Animal; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000097:blood* / Q000175:diagnosis; D009368:Neoplasm Transplantation; D054464:Peroxiredoxins / Q000097:blood*; D040901:Proteomics / Q000379:methods; D014183:Transplantation, Heterologous; D015854:Up-Regulation
D014408:Biomarkers, Tumor; D002232:Carbocyanines; D005456:Fluorescent Dyes; C089187:cyanine dye 3; C085321:cyanine dye 5; D054464:Peroxiredoxins; D024402:Carbonic Anhydrase II