Identification of tumor antigens in human lung squamous carcinoma by serological proteome analysis.
Autoantibodies against tumor antigens are promising means for cancer diagnosis and prognosis. In this study, we applied a proteomic approach to identify proteins that commonly elicit humoral response in lung squamous carcinoma (LSC). Sera from 20 newly diagnosed patients with LSC and 20 matched healthy individuals were analyzed for antibody-based reactivity against LSC proteins separated by two-dimensional electrophoresis. Autoantibodies against triosephosphate isomerase (Tim) and superoxide dismutase [Mn] (MnSOD) were detected in sera from over 20% patients with LSC but none from the normal controls. Furthermore, the occurrence of autoantibodies against Tim and MnSOD was evaluated by ELISA in an additional 40 LSC patients, 30 other types of cancer (OTC) patients, and 50 noncancer controls (NC). Results showed that frequency of autoantibody against Tim (27.5%) in LSC patients was significantly higher than that in OTC patients (6.7%, p = 0.027) and in NC (6%, p = 0.005). Likewise, frequency of autoantibody against MnSOD in LSC (20%) patients was significantly higher than that in NC (4%, p = 0.016), however, there was no significant difference when comparing to that in OTC patients (6.7%, p = 0.115). We also observed significantly increased expression and secretion of Tim and MnSOD in LSC, which possibly account for their autoantibody development. Our results indicate that autoantibody and antigen of Tim and MnSOD may be useful for screening and diagnosis of the lung squamous carcinoma.
Yang
Fang
F
Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, #87 Xiangya Road, Changsha 410078, Hunan, China.
Xiao
Zhi-qiang
ZQ
Zhang
Xiu-zhi
XZ
Li
Cui
C
Zhang
Peng-fei
PF
Li
Mao-yu
MY
Chen
Ying
Y
Zhu
Ge-qin
GQ
Sun
Yi
Y
Liu
Ying-fu
YF
Chen
Zhu-Chu
ZC
D000595:Amino Acid Sequence; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000097:blood / Q000737:chemistry / Q000302:isolation & purification; D001323:Autoantibodies / Q000097:blood; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000737:chemistry* / Q000201:enzymology; D015180:Electrophoresis, Gel, Two-Dimensional; D004797:Enzyme-Linked Immunosorbent Assay; D004798:Enzymes / Q000097:blood / Q000737:chemistry / Q000302:isolation & purification; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood / Q000737:chemistry* / Q000201:enzymology; D008969:Molecular Sequence Data; D040901:Proteomics / Q000379:methods*; D012016:Reference Values
D000951:Antigens, Neoplasm; D001323:Autoantibodies; D004798:Enzymes