To investigate whether MMP13 expression is necessary for the induction of tumors by ETV4 in vivo, MMT-ETV4 + shCtrl and MMT-ETV4 + shMMP13 cells were injected into the inguinal flanks of immunocompromised mice, and tumor growth was evaluated every 3–4 days (Fig. 6). The gene discussed is MMP13; the disease is neoplasm.