To further specify the role of HMGA1 on the proliferation of BC and exclude the influences of other cell types in matrigel or on ALI assays, we performed the HMGA1 siRNA transfection in the expanding BC, and assessed the expression of proliferation marker MKI67 by TaqMan and compared the cell number of control and HMGA1-silenced BC at the end of the BC culture. The gene discussed is HMGA1; the disease is breast cancer.