title: Expression of cancer-testis antigens (MAGE-A1, MAGE-A3/6, MAGE-A4, MAGE-C1 and NY-ESO-1) in primary human uveal and conjunctival melanoma.
abstract: OBJECTIVE
  Metastatic disease in ocular melanoma remains untreatable, is associated with late detection and is resistant to conventional systemic therapies. Many tumours including cutaneous melanoma express specific cancer-testis (CT) antigens and vaccines targeting these antigens can induce T-cell-mediated and humoural immune responses. The authors examined primary uveal and conjunctival melanomas for expression of CT antigens to assess their potential as targets for ocular melanoma immunotherapy.
  
  
  METHODS
  Paraffin-embedded uveal (n=32) and conjunctival (n=15) melanomas were assessed by immunohistochemistry for melanocyte differentiation antigens (gp100, Melan-A/MART-1 and tyrosinase), and CT antigens (MAGE-A1, MAGE-A3/6, MAGE-A4, MAGE-C1 and NY-ESO-1).
  
  
  RESULTS
  Melanoma differentiation antigens, gp100, Melan-A/MART1 and tyrosinase, were expressed in >75% of tumour cells in all uveal and conjunctival melanomas tested. Expression of all five CT antigens tested was low in uveal melanomas, and when present, stained <25% of the tumour cells. MAGE-A1, MAGE-A4 and NY-ESO-1 were expressed in <10% of tumour cells in conjunctival melanomas, while MAGE-C1 and MAGE-A3/6 were expressed in ∼20% and ∼35% of tumour cells in this malignancy, respectively, with variable expression levels.
  
  
  CONCLUSIONS
  Uveal and conjunctival melanomas consistently expressed high levels of the differentiation antigens (gp100, Melan-A/MART1 and tyrosinase). However, compared with other tumours, including cutaneous melanoma, only low levels of CT antigens were found in ocular melanomas. These observations suggest that immunotherapy directly targeting the CT antigens studied may not be effective for ocular melanoma.
authors.affiliation: School of Optometry & Vision Science, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: J A
authors.initials: JA
authors.lastname: Errington
authors.forename: R M
authors.initials: RM
authors.lastname: Conway
authors.forename: N
authors.initials: N
authors.lastname: Walsh-Conway
authors.forename: J
authors.initials: J
authors.lastname: Browning
authors.forename: C
authors.initials: C
authors.lastname: Freyer
authors.forename: J
authors.initials: J
authors.lastname: Cebon
authors.forename: M C
authors.initials: MC
authors.lastname: Madigan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000943:Antigens, Differentiation / Q000378:metabolism; D000951:Antigens, Neoplasm / Q000378:metabolism*; D003230:Conjunctival Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008545:Melanoma / Q000378:metabolism* / Q000473:pathology; D058950:Melanoma-Specific Antigens / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D014604:Uveal Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D000943:Antigens, Differentiation; D000951:Antigens, Neoplasm; C104948:CTAG1B protein, human; C072011:MAGEA1 protein, human; C072013:MAGEA3 protein, human; C095204:MAGEA4 protein, human; C095203:MAGEA6 protein, human; C110905:MAGEC1 protein, human; D058950:Melanoma-Specific Antigens; D008565:Membrane Proteins; D009363:Neoplasm Proteins