title: Characterization of a cancer/testis (CT) antigen gene family capable of eliciting humoral response in cancer patients.
abstract: Cancer/testis (CT) antigens are immunogenic proteins expressed in normal gametogenic tissues and in different types of tumors. CT antigens are promising candidates for cancer immunotherapy, and the identification of novel CT antigens is a prerequisite for the development of cancer vaccines. We have identified a CT antigen, named CTSP-1, with partial similarity to the breast differentiation antigen NY-BR-1. CTSP-1 presents several splicing and polyadenylation variants and has a very restricted expression pattern among normal tissues. CTSP-1 is exclusively expressed in normal testis and is aberrantly expressed in 47.6% (10 of 21) of tumor cell lines and in 44.4% (75 of 169) of tumors from different histological types. The highest percentages of positive expression were observed in melanomas (59.0%) followed by prostate (58.0%) and lung (57.0%) tumors. CTSP-1 is part of a highly conserved gene family, and members of this family also have a restricted expression pattern and similar protein structure. Antibodies against members of this gene family were detected in 10% (14 of 141) of plasma samples from patients with a wide spectrum of tumors. The highest percentages of antibody response were observed in patients with prostate (20.8%), thyroid (20.0%), and breast (16.6%) tumors. Because of its very restricted expression pattern in normal tissues and immunogenicity in different types of tumors, CTSP-1 should be considered a promising candidate for cancer immunotherapy.
authors.affiliation: Ludwig Institute for Cancer Research, SP 01509-010, São Paulo, Brazil.
authors.forename: Raphael B
authors.initials: RB
authors.lastname: Parmigiani
authors.forename: Fabiana
authors.initials: F
authors.lastname: Bettoni
authors.forename: Maria D
authors.initials: MD
authors.lastname: Vibranovski
authors.forename: Marilene H
authors.initials: MH
authors.lastname: Lopes
authors.forename: Waleska K
authors.initials: WK
authors.lastname: Martins
authors.forename: Isabela W
authors.initials: IW
authors.lastname: Cunha
authors.forename: Fernando A
authors.initials: FA
authors.lastname: Soares
authors.forename: Andrew J G
authors.initials: AJ
authors.lastname: Simpson
authors.forename: Sandro J
authors.initials: SJ
authors.lastname: de Souza
authors.forename: Anamaria A
authors.initials: AA
authors.lastname: Camargo
mesh_terms: D017398:Alternative Splicing / Q000235:genetics; D000818:Animals; D000951:Antigens, Neoplasm / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D014644:Genetic Variation / Q000235:genetics; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D009687:Nuclear Proteins / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D026723:Polyadenylation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; C473315:CAGE1 protein, human; D009687:Nuclear Proteins; D012333:RNA, Messenger