Expression of SSX genes in human tumors

Int J Cancer. 1998 Jul 3;77(1):19-23. doi: 10.1002/(sici)1097-0215(19980703)77:1<19::aid-ijc4>;2-2.


The HOM-MEL-40 antigen which is encoded by the SSX-2 gene was originally detected as a tumor antigen recognized by autologous IgG antibodies in a melanoma patient. Expression analysis demonstrated that SSX-2 is a member of the recently described cancer/testis antigen (CTA) class as it is expressed in a variety of different human neoplasms, but not in normal tissues with the exception of testis and a weak expression in the thyroid. Further studies demonstrated that SSX-2 belongs to a gene family consisting of at least 5 homologous genes. We now report the analysis of the expression of all 5 SSX genes in 325 specimens of human neoplasms from various histological origins, using reverse transcription polymerase chain reaction (RT-PCR). SSX-1, -2, and -4 were found to be expressed in 8%, 15% and 15%, of the tumors, respectively, while the expression of the SSX-5 gene was rare (7/325), and SSX-3 expression was not detected. For defined tumor types, expression of at least one of the SSX family members was most frequently observed in head and neck cancer (75%), followed by ovarian cancer (50%), malignant melanoma (43%), lymphoma (36%), colorectal cancer (27%) and breast cancer (23%), while leukemias and the few cases of leiomyosarcomas, seminomas and thyroid cancers were found not to express any SSX gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Neoplasm / genetics*
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Neoplasm Proteins / genetics*
  • Neoplasms / genetics*
  • Polymerase Chain Reaction
  • Repressor Proteins / genetics*


  • Antigens, Neoplasm
  • Neoplasm Proteins
  • Repressor Proteins
  • synovial sarcoma X breakpoint proteins