The over expression of SSX genes (−1, −2, −2B and −3) documented in C2 is another illustrative case, especially considering that the sample pool did not include synovial sarcoma samples (even though the over expression of SSX genes may also be found in other STS histotypes, with a significant fraction of these STSs co-over expressing more than one SSX family member [44,45,46]). This evidence concerns the gene SSX2B and synovial sarcoma.