Cancer testis antigen OY-TES-1 expression and serum immunogenicity in colorectal cancer: its relationship to clinicopathological parameters

• Published in: International journal of clinical and experimental pathology Vol. 6; no. 12; pp. 2835 - 2845
• Main Authors: Luo, Bin, Yun, Xiang, Fan, Rong, Lin, Yong-Da, He, Shu-Jia, Zhang, Qing-Mei, Mo, Fa-Rong, Chen, Fang, Xiao, Shao-Wen, Xie, Xiao-Xun
• Format: Journal Article
• Language: English
• Published: United States e-Century Publishing Corporation 01.01.2013
• Subjects: Adenoma - blood; Adenoma - genetics; Adenoma - immunology; Adenoma - pathology; Adult; Aged; Aged, 80 and over; Autoantibodies - blood; Biomarkers, Tumor - analysis; Biomarkers, Tumor - genetics; Biomarkers, Tumor - immunology; Carrier Proteins - analysis; Carrier Proteins - genetics; Carrier Proteins - immunology; Case-Control Studies; Colorectal Neoplasms - blood; Colorectal Neoplasms - genetics; Colorectal Neoplasms - immunology; Colorectal Neoplasms - pathology; Female; Humans; Immunity, Humoral; Immunohistochemistry; Male; Middle Aged; Neoplasm Grading; Neoplasm Invasiveness; Neoplasm Staging; Original; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - analysis; OY-TES-1; Cancer testis antigen; colorectal cancer
• ISSN: 1936-2625; 1936-2625

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.