title: Expression of the sperm fibrous sheath protein CABYR in human cancers and identification of α-enolase as an interacting partner of CABYR-a.
abstract: Calcium-binding tyrosine phosphorylation regulated protein (CABYR), a family of isoforms resulting from alternative splicing, has been identified as a cancer/testis antigen (CT88) in lung cancer and hypothesized to be a promising target for immunotherapy. Here, we report the expression of CABYR in various cancer tissues/cell lines. Expression profiles of individual isoforms were different among cancers. Furthermore, protein and mRNA levels did not correlate for individual isoforms. While CABYR-c/d were the most abundant splicing variants, CABYR-a was the predominant protein isoform. Finally, CABYR-a, but not CABYR-c, was found to interact with α-enolase in vivo. Collectively, the data indicate that CABYR is a CT antigen widely expressed in diverse cancer cells. However, individual protein isoforms may be differentially regulated by post-transcriptional and post-translational mechanisms and may have a unique role in carcinogenesis. The protein expression pattern of various CABYR isoforms is important with regard to the consideration of using CABYR as a target antigen for the development of vaccines for cancer therapy.
authors.affiliation: Institute of Molecular Βiology, National Chung Hsing University, Taichung 402, Taiwan, ROC.
authors.forename: Yen-Tzu
authors.initials: YT
authors.lastname: Tseng
authors.forename: Jiun-Yi
authors.initials: JY
authors.lastname: Hsia
authors.forename: Chun-Yu
authors.initials: CY
authors.lastname: Chen
authors.forename: Nien-Tsung
authors.initials: NT
authors.lastname: Lin
authors.forename: Pele Choi-Sing
authors.initials: PC
authors.lastname: Chong
authors.forename: Chiou-Ying
authors.initials: CY
authors.lastname: Yang
mesh_terms: D017398:Alternative Splicing; D015139:Blotting, Southern; D015153:Blotting, Western; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004938:Esophageal Neoplasms / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D047468:Immunoprecipitation; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism*; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010751:Phosphopyruvate Hydratase / Q000235:genetics / Q000378:metabolism*; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
chemical_list: C448922:CABYR protein, human; D002135:Calcium-Binding Proteins; D010750:Phosphoproteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D010751:Phosphopyruvate Hydratase