POU5F1 and breast cancer: Notably, we also observed that co-cultures with BC cells significantly reduced mRNA levels of multipotency markers OCT4 (about 30% reduction upon co-culture with MCF7), SOX2 (about 80% reduction upon co-culture with both MCF7 and MDA-MB231) and NANOG (about 80% reduction upon co-culture with MDA-MB231) in MAT-MSCs (Figure 3a; adjp < 0.05).