In breast cancer, SMAD7 expression is decreased by the overexpression of SET domain divergent histone lysine methyltransferase 1 (SETDB1), while knockdown of SETDB1 upregulates SMAD7 expression, thereby inhibiting breast cancer metastasis, suggesting that increased SMAD7 expression improves patient survival [121]. The gene discussed is SMAD7; the disease is breast cancer.