title: Cancer testis antigen OY-TES-1 expression and serum immunogenicity in colorectal cancer: its relationship to clinicopathological parameters.
abstract: Cancer testis (CT) antigens are attractive targets for cancer immunotherapy because their expression is restricted in normal germ line tissues but frequently detected in variety of tumors. OY-TES-1 is identified as a member of CT antigens. Current knowledge about OY-TES-1 expression in colorectal cancer (CRC) is solely based on mRNA analysis. None of previous researches has studied OY-TES-1 at protein level. In this study, OY-TES-1 polyclonal antibody was generated. The expression of OY-TES-1 mRNA and protein was detected by RT-PCR and immunohistochemistry in 60 CRC and paired adjacent non-tumor tissues, 24 colorectal adenoma and 3 normal colon tissues, respectively. Sera from 73 CRC patients were also tested for OY-TES-1 antibody by ELISA. Our results showed that the frequency of OY-TES-1 mRNA expression was statistically higher in CRC (73.3%, 44/60) than that in adjacent non-tumor tissue (55.0%, 33/60) and colorectal adenoma (45.8%, 11/24). For the first time, OY-TES-1 protein expression was found in (43.3%, 26/60) of CRC tissues, but absent in any of adjacent non-tumor and colorectal adenoma tissues. No OY-TES-1 expression was found in normal colon by either RT-PCR or immunohistochemistry. Furthermore, OY-TES-1 protein expression was correlated with tumor invasion stage (P=0.004) and histological grade (P=0.040). Anti-OY-TES-1 antibody was detected in (9.6%, 7/73) of CRC patients' sera but not in 76 healthy donors. This finding demonstrates that OY-TES-1 is frequently expressed in CRC and is able to induce humoral immune response spontaneously in CRC patients, suggesting that it might be a promising immunotherapy target for CRC.
authors.affiliation: Department of Histology & Embryology, School of Pre-clinical Medicine, First Affiliated Hospital, Guangxi Medical University Nanning 530021, Guangxi Zhuang Autonomous Region, China ; Central Laboratory of Pre-clinical Medicine, First Affiliated Hospital, Guangxi Medical University Nanning 530021, Guangxi Zhuang Autonomous Region, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Luo
authors.forename: Xiang
authors.initials: X
authors.lastname: Yun
authors.forename: Rong
authors.initials: R
authors.lastname: Fan
authors.forename: Yong-Da
authors.initials: YD
authors.lastname: Lin
authors.forename: Shu-Jia
authors.initials: SJ
authors.lastname: He
authors.forename: Qing-Mei
authors.initials: QM
authors.lastname: Zhang
authors.forename: Fa-Rong
authors.initials: FR
authors.lastname: Mo
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.forename: Shao-Wen
authors.initials: SW
authors.lastname: Xiao
authors.forename: Xiao-Xun
authors.initials: XX
authors.lastname: Xie
mesh_terms: D000236:Adenoma / Q000097:blood / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000097:blood / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D005260:Female; D006801:Humans; D056724:Immunity, Humoral; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: C485651:ACRBP protein, human; D001323:Autoantibodies; D014408:Biomarkers, Tumor; D002352:Carrier Proteins; D012333:RNA, Messenger
keywords: Cancer testis antigen; OY-TES-1; colorectal cancer