TGFB1 and triple-negative breast carcinoma: To determine whether there was an association between TGFβ induction of cyclin D1 and TGFβ's pro-migratory effect, we measured the mRNA level of cyclin D1 in a panel of triple negative breast cancer cell lines which are either insensitive (SUM1315) or responsive (SUM149 and SUM159) to TGFβ-mediated cell migration and invasion [44].