ADAM17 and synovial sarcoma: Because ADAM17 has been extensively implicated in metastasis [18, 26–33] and its mutations detected in our multiple metastatic SS samples in different patients, but not in primary SS (Table 1), we decided to choose ADAM17-P729H and ADAM17-K805T in our first attempt to reveal the potential impacts of the mutations identified solely in metastatic SS.