In consequence, in the absence of doxycycline, A673 Ewing sarcoma cells produce high levels of EWSR1::FLI1 (EWSR1::FLI1high), while in the presence of doxycycline, low levels of EWSR1::FLI1 (EWSR1::FLI1low) are achieved. The gene discussed is EWSR1; the disease is Ewing sarcoma.