MYF5 and neoplasm: Similarly, the use of ABT-263, a BH3-peptidomimetic inhibitor of BCL2, BCL-XL, and BCLW, despite a limited activity in vitro as a single agent against mouse SyS cells, was able to hamper synovial sarcomagenesis in vivo in the SyS mouse model Myf5–Cre/hSS2, significantly reducing tumor number and dimensions [42].