Enhanced interferon signaling pathway in oral cancer revealed by quantitative proteome analysis of microdissected specimens using 16O/18O labeling and integrated two-dimensional LC-ESI-MALDI tandem MS.
Oral squamous cell carcinoma (OSCC) remains one of the most common cancers worldwide, and the mortality rate of this disease has increased in recent years. No molecular markers are available to assist with the early detection and therapeutic evaluation of OSCC; thus, identification of differentially expressed proteins may assist with the detection of potential disease markers and shed light on the molecular mechanisms of OSCC pathogenesis. We performed a multidimensional (16)O/(18)O proteomics analysis using an integrated ESI-ion trap and MALDI-TOF/TOF MS system and a computational data analysis pipeline to identify proteins that are differentially expressed in microdissected OSCC tumor cells relative to adjacent non-tumor epithelia. We identified 1233 unique proteins in microdissected oral squamous epithelia obtained from three pairs of OSCC specimens with a false discovery rate of <3%. Among these, 977 proteins were quantified between tumor and non-tumor cells. Our data revealed 80 dysregulated proteins (53 up-regulated and 27 down-regulated) when a 2.5-fold change was used as the threshold. Immunohistochemical staining and Western blot analyses were performed to confirm the overexpression of 12 up-regulated proteins in OSCC tissues. When the biological roles of 80 differentially expressed proteins were assessed via MetaCore analysis, the interferon (IFN) signaling pathway emerged as one of the most significantly altered pathways in OSCC. As many as 20% (10 of 53) of the up-regulated proteins belonged to the IFN-stimulated gene (ISG) family, including ubiquitin cross-reactive protein (UCRP)/ISG15. Using head-and-neck cancer tissue microarrays, we determined that UCRP is overexpressed in the majority of cheek and tongue cancers and in several cases of larynx cancer. In addition, we found that IFN-beta stimulates UCRP expression in oral cancer cells and enhances their motility in vitro. Our findings shed new light on OSCC pathogenesis and provide a basis for the future development of novel biomarkers.
Chi
Lang-Ming
LM
Molecular Medicine Research Center, College of Medicine, Chang Gung University, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan.
Lee
Chien-Wei
CW
Chang
Kai-Ping
KP
Hao
Sheng-Po
SP
Lee
Hang-Mao
HM
Liang
Ying
Y
Hsueh
Chuen
C
Yu
Chia-Jung
CJ
Lee
I-Neng
IN
Chang
Yin-Ju
YJ
Lee
Shih-Ying
SY
Yeh
Yuan-Ming
YM
Chang
Yu-Sun
YS
Chien
Kun-Yi
KY
Yu
Jau-Song
JS
D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002853:Chromatography, Liquid / Q000379:methods; D030562:Databases, Protein; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007372:Interferons / Q000378:metabolism*; D008297:Male; D042282:Microdissection; D008969:Molecular Sequence Data; D009062:Mouth Neoplasms / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D010103:Oxygen Isotopes / Q000378:metabolism*; D020543:Proteome / Q000032:analysis*; D015398:Signal Transduction / Q000502:physiology*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods; D046888:Tissue Array Analysis
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D010103:Oxygen Isotopes; D020543:Proteome; D007372:Interferons