title: Melanoma-associated antigens in esophageal adenocarcinoma: identification of novel MAGE-A10 splice variants.
abstract: OBJECTIVE
  The melanoma-associated antigens (MAGEs) are tumor-specific antigens recognized by cytotoxic T lymphocytes. In this study, expression of MAGE family A members was evaluated during the development of esophageal adenocarcinoma (EA) as potential targets for immunotherapy.
  
  
  METHODS
  MAGE-A mRNA expression was evaluated in 46 samples including Barrett's metaplasia (BM), dysplasia, and EA using oligonucleotide microarrays. Expression of MAGE-A proteins was confirmed by immunohistochemistry on tissue microarrays containing 59 EA, 11 dysplasia, and 9 BM samples and by Western blot. To further evaluate MAGE-A10 expression, reverse transcription-polymerase chain reaction (RT-PCR) products were sequenced, and protein expression was determined using a specific antibody.
  
  
  RESULTS
  Overexpression of MAGE-A1, MAGE-A2b, MAGE-A3, MAGE-A4, MAGE-A6, MAGE-A9, MAGE-A10, and MAGE-A12 was found in EAs relative to BM on oligonucleotide microarrays. MAGE-A3 overexpression was confirmed by real-time RT-PCR in 21.4% (6 of 28) of esophageal tumors. Immunohistochemistry on tissue microarray revealed MAGE-A proteins in 20.3% (12 of 59) of EAs and MAGE-A10 staining in 16.9% (10 of 59) of EAs. MAGE-A expression was confirmed by Western blot in several esophageal tumors and in two EA cell lines, Flo-1 and Seg-1, whereas Flo-1 also expressed MAGE-A10. Tumors produced from these cell lines in nude mice retained MAGE-A expression. Interestingly, RT-PCR in primary tumors expressing MAGE-A10 protein revealed additional PCR products that were identified as novel MAGE-A10 alternative splice variants using DNA sequencing.
  
  
  CONCLUSIONS
  This is the first report of these MAGE-A10 alternative splice sequences, and characterization of MAGE-A expression may provide potential targets for immunotherapy in patients with EA.
authors.affiliation: Department of Surgery, Section of General Thoracic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA.
authors.forename: Jules
authors.initials: J
authors.lastname: Lin
authors.forename: Lin
authors.initials: L
authors.lastname: Lin
authors.forename: Dafydd G
authors.initials: DG
authors.lastname: Thomas
authors.forename: Joel K
authors.initials: JK
authors.lastname: Greenson
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Giordano
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Robinson
authors.forename: Ruteja A
authors.initials: RA
authors.lastname: Barve
authors.forename: Frank A
authors.initials: FA
authors.lastname: Weishaar
authors.forename: Jeremy M G
authors.initials: JM
authors.lastname: Taylor
authors.forename: Mark B
authors.initials: MB
authors.lastname: Orringer
authors.forename: David G
authors.initials: DG
authors.lastname: Beer
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D017398:Alternative Splicing; D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics* / Q000378:metabolism; D001471:Barrett Esophagus / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014408:Biomarkers, Tumor / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D004938:Esophageal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D058950:Melanoma-Specific Antigens; D008679:Metaplasia / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; C119317:MAGE-A10 antigen; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins; D012333:RNA, Messenger