Disease relevance of SSX4

• Recently, however, it was found that these two genes, as well as the highly homologous SSX4 and SSX5 genes, are aberrantly expressed in different types of cancers, including melanomas [1].
• This was also observed in a synovial sarcoma tumor expressing SYT/SSX4 [2].
• We found relatively high SSX4 mRNA expression in endometrial cancer (24%), ovarian cancer (13%), and cervical cancer (20%) [3].
• SSX-4 was the only CT gene expressed in oligodendrogliomas (2 of 5 cases), and it was also expressed in oligoastrocytomas (3 of 4 cases) and astrocytomas (10 of 37 cases) [4].
• Among 46 primary lung cancers, high expression rates were found for MAGE-3 (41%, 19/46), and SSX-4 (35%, 16/46) [5].

High impact information on SSX4

• Re: A novel fusion gene, SYT-SSX4, in synovial sarcoma [6].
• A novel fusion gene, SYT-SSX4, in synovial sarcoma [7].
• In the present study, we developed a monoclonal antibody found to recognize SSX2, SSX3, and SSX4 proteins expressed in formaldehyde-fixed and paraffin-embedded tissues [1].
• Upon in vitro stimulation of PBMC from four melanoma patients bearing Ag-expressing tumors with a pool of long peptides spanning the protein sequence, we detected and isolated SSX-4-specific CD4+ T cells recognizing several distinct antigenic sequences, mostly restricted by frequently expressed HLA class II alleles [8].
• CD4+ T cell responses to SSX-4 in melanoma patients [8].

Biological context of SSX4

• Genomic cloning of a prototype SSX gene (SSX2) showed that its coding region is encoded by 6 exons, and the shortened form of SSX4 cDNA represents an alternatively spliced product lacking the 5th exon [9].
• Stable transfection of an SYT/SSX4 expression vector into human and murine cell lines correlated with a down-regulation of SYT transcripts [2].
• The evidence of humoral immunity to SSX-2 and SSX-4, and SSX-4-specific CD4(+) T cells among circulating lymphocytes in patients with antigen expressing EOC suggest that these antigens are attractive targets for specific immunotherapy in EOC [10].

Anatomical context of SSX4

• In this study, we have analyzed CD4+ T cell responses directed against the Ag encoded by SSX-4 [8].
• All normal tissues (n=6), with the exception of testis, normal bone marrow (BM, n=12) and normal peripheral blood (PBL, n=10) were negative for SSX-2 and SSX-4 expression [11].

Regulatory relationships of SSX4

• Seventy-two percent (13/18) of stage 4 NB expressed SSX-2 and 67% (12/18) expressed SSX-4 [11].

Other interactions of SSX4

• SSX-1 was the most frequently expressed family member, followed by SSX-4, -2 and -5 [12].

Analytical, diagnostic and therapeutic context of SSX4

• Antibodies to SSX-2 and SSX-4 were detectable by ELISA and RAYS in two patients [10].
• In this study, sixty-seven neuroblastomas (NB) (12 stage 1, 13 stage 2, 12 stage 3, 12 stage 4S and 13 stage 4) were examined by RT-PCR and a sensitive chemiluminescent detection method for SSX-2 and SSX-4 expression [11].

References