Identification of novel nasopharyngeal carcinoma biomarkers by laser capture microdissection and proteomic analysis.
OBJECTIVE
To identify novel nasopharyngeal carcinoma (NPC) biomarkers by laser capture microdissection and a proteomic approach.


METHODS
Proteins from pooled microdissected NPC and normal nasopharyngeal epithelial tissues (NNET) were separated by two-dimensional gel electrophoresis, and differential proteins were identified by mass spectrometry. Expression of three differential proteins (stathmin, 14-3-3sigma, and annexin I) in the above two tissues as well as four NPC cell lines was determined by Western blotting. Immunohistochemistry was also done to detect the expression of three differential proteins in 98 cases of primary NPC, 30 cases of NNET, and 20 cases of cervical lymph node metastases, and the correlation of their expression levels with clinicopathologic features and clinical outcomes were evaluated.


RESULTS
Thirty-six differential proteins between the NPC and NNET were identified. The expression levels of stathmin, 14-3-3sigma, and annexin I in the two types of tissues were confirmed and related to differentiation degree and/or metastatic potential of the NPC cell lines. Significant stathmin up-regulation and down-regulation of 14-3-3sigma and annexin I were observed in NPC versus NNET, and significant down-regulation of 14-3-3sigma and annexin I was also observed in lymph node metastasis versus primary NPC. In addition, stathmin up-regulation and down-regulation of 14-3-3sigma and annexin I were significantly correlated with poor histologic differentiation, advanced clinical stage, and recurrence, whereas down-regulation of 14-3-3sigma and annexin I was also significantly correlated with lymph node and distant metastasis. Furthermore, survival curves showed that patients with stathmin up-regulation and down-regulation of 14-3-3sigma and annexin I had a poor prognosis. Multivariate analysis revealed that the expression status of stathmin, 14-3-3sigma, and annexin I was an independent prognostic indicator.


CONCLUSIONS
The data suggest that stathmin, 14-3-3sigma, and annexin I are potential biomarkers for the differentiation and prognosis of NPC, and their dysregulation might play an important role in the pathogenesis of NPC.
Cheng
Ai-Lan
AL
Key Laboratory of Cancer Proteomics of Chinese Ministry of Health and Medical Research Center, Xiangya Hospital, Xiangya School of Medicine, Central South University, Changsha, Hunan Province, China.
Huang
Wei-Guo
WG
Chen
Zhu-Chu
ZC
Peng
Fang
F
Zhang
Peng-Fei
PF
Li
Mao-Yu
MY
Li
Feng
F
Li
Jian-Ling
JL
Li
Cui
C
Yi
Hong
H
Yi
Bin
B
Xiao
Zhi-Qiang
ZQ
D048948:14-3-3 Proteins / Q000378:metabolism; D017305:Annexin A1 / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D045744:Cell Line, Tumor; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism* / Q000401:mortality; D040901:Proteomics / Q000379:methods*; D050777:Stathmin / Q000378:metabolism
D048948:14-3-3 Proteins; D017305:Annexin A1; D014408:Biomarkers, Tumor; C493995:STMN1 protein, human; D050777:Stathmin; C482984:YWHAH protein, human