HDAC9 and synovial sarcoma: To determine if the combination ofHsp90 inhibitors and HDAC inhibitors are able to synergize on synovial sarcoma,an in vitro MTT cellproliferation assay was performed on the synovial sarcoma cell lines SYO-1 andFuji using the Hsp90 inhibitor 17-AAG and the HDAC inhibitor MS-275.