Luo Chonglin, Xiao Xueyuan, Liu Danhui, Chen Shaosong, Li Mingying, Xu Anjian, Liu Jifu, Gao Shugeng, Wu Shanshan, He Dacheng
Key laboratory of Cell Proliferation and Regulation of Ministry of Education, Beijing Normal University, China.
Clin Cancer Res. 2007 Feb 15;13(4):1288-97. doi: 10.1158/1078-0432.CCR-06-1742.
Cancer-testis (CT) antigens are often expressed in a proportion of tumors of various types. Their restricted normal tissue expression and immunogenicity make them potential targets for immunotherapy. CABYR is a calcium-binding tyrosine phosphorylation-regulated fibrous sheath protein initially reported to be testis specific and subsequently shown to be present in brain tumors. This study was to determine whether CABYR is a novel CT antigen in lung cancer.
mRNA expression of CABYR-a/b (combination of CABYR-a and CABYR-b) and CABYR-c was examined in 36 lung cancer specimens, 14 cancer cell lines, and 1 normal cell line by conventional and real-time reverse transcription-PCR. Protein expression of CABYR was analyzed in 50 lung cancer tissues by immunohistochemistry. Antibodies specific to CABYR were analyzed in sera from 174 lung cancer patients and 60 healthy donors by ELISA and Western blot.
mRNA expression of CABYR-a/b and CABYR-c was observed, respectively, in 13 and 15 of 36 lung cancer tissues as well as in 3 and 5 of 14 cancer cell lines, whereas neither of them was observed in adjacent noncancerous tissues or the normal cell line. Protein expression of CABYR-a/b and CABYR-c was observed, respectively, in 20 and 19 of 50 lung cancer tissues. IgG antibodies specific to CABYR-a/b and CABYR-c were detected, respectively, in 11% and 9% of sera from lung cancer patients but not from the 60 healthy donors.
CABYR is a novel CT antigen in lung cancer and may be a promising target for immunotherapy for lung cancer patients.
癌-睾丸（CT）抗原常在多种类型肿瘤的一定比例中表达。其在正常组织中的限制性表达和免疫原性使其成为免疫治疗的潜在靶点。CABYR是一种钙结合酪氨酸磷酸化调节的纤维鞘蛋白，最初报道为睾丸特异性，随后发现其存在于脑肿瘤中。本研究旨在确定CABYR是否为肺癌中的一种新型CT抗原。
通过常规和实时逆转录PCR检测36例肺癌标本、14种癌细胞系和1种正常细胞系中CABYR-a/b（CABYR-a和CABYR-b的组合）和CABYR-c的mRNA表达。采用免疫组织化学分析50例肺癌组织中CABYR的蛋白表达。通过ELISA和蛋白质印迹法分析174例肺癌患者和60例健康供者血清中针对CABYR的特异性抗体。
在36例肺癌组织中的13例以及14种癌细胞系中的3例中分别观察到CABYR-a/b的mRNA表达，在36例肺癌组织中的15例以及14种癌细胞系中的5例中分别观察到CABYR-c的mRNA表达，而在相邻的非癌组织或正常细胞系中均未观察到。在50例肺癌组织中的20例和19例中分别观察到CABYR-a/b和CABYR-c蛋白表达。在11%的肺癌患者血清中检测到针对CABYR-a/b的IgG抗体，在9%的肺癌患者血清中检测到针对CABYR-c的IgG抗体，而在60例健康供者血清中均未检测到。
CABYR是肺癌中的一种新型CT抗原，可能是肺癌患者免疫治疗的一个有前景的靶点。
