We found that the SYT-SSX fusion protein produces a dominant-negative function for SYT, which is a transcriptional coactivator.     ///    The SYT-SSX fusion protein down-regulates the cell proliferation regulator COM1 in t(x;18) synovial sarcoma.     ///    "Although SYT-SSX fusion proteins appear to trigger synovial sarcoma development, little is known about the downstream targets of SYT-SSX. "    ///    The SYT-SSX fusion protein down-regulates the cell proliferation regulator COM1 in t(x;18) synovial sarcoma.. 