However, we observed an enhanced growth phenotype in ER+ MCF7 cells, supporting the notion that TGFβ mediates tumor-suppressive phenotypes in more differentiated breast cancer cells and pro-tumorigenic effects in less differentiated cell types (Figure 2—figure supplement 1F; Tian et al., 2003; Massagué, 2008). The gene discussed is TGFB1; the disease is neoplasm.