Fig. 7
From: Oncogene activated human breast luminal progenitors contribute basally located myoepithelial cells
PIK3CAH1047R-iHBECCD117 bipotent progenitors express luminal- and myoepithelial lineage programs. A Micrographs of luminal progenitor cells cultured in 3D in Matrigel™/collagen matrix with fibroblasts. Phase contrast micrograph (left) shows acinus-like spheres with a central lumen and at a size of approximately 50 µm after two weeks of culture. A representative multicolor imaging (right) of cryostat sections of 3D gels stained for K19 (red) and K14 (green). Note the correctly polarized position of luminal and myoepithelial-like cells. Nuclei are stained blue with DAPI. Scale bar = 50 µm. B Multicolor imaging of cryostat sections of PIK3CAH1047R-iHBECCD117 transplanted to NOG mice together with fibroblasts and a Matrigel™/collagen matrix. Polarity and lumen formation are highlighted by staining of the K19+ luminal cells (red, left column) against basal keratin K14 and apical MUC 1 (green, left column). Myoepithelial differentiation is highlighted by staining for aSMA and p63 (red, right column) against K14 (green, right column). Nuclei are stained with DAPI (blue). n = 12 injections. Scale bar = 20 µm