TGFB1 and breast carcinoma: Similarly, 1 mg/Kg SB431542 was determined as the suboptimal dose to be used here considering previous reports.43,44 To quantify the TGF-β signaling activity in breast cancer cells in vivo, MDA231 and MDA.Gluc cells were implanted in NOD-SCID mice (Fig. 8a, b).