OCT4-transduced breast cells (OTBCs) generate primary tumors and experimental metastases upon injection in immunodeficient mice. (a) Representative image of a prototype subcutaneous primary tumor generated by OTBCs86-L1-DsRed cells. Control mice were injected with the parental p86 line. Animals were injected with 1 × 106 cells; for simplicity, only one animal is shown. The OTBCs86-L1-DsRed was engineered with a lentiviral vector expressing the DsRed gene, which facilitated tumor measurement by fluorescence imaging (IVIS-kinetic; Xenogen). Shown is a representative paraffin-embedded tumor section stained with (b) OCT4 (40×), (c) hematoxylin and eosin (H&E) (40×), (d) H&E magnification from (c), (e) vimentin (VIM) (20×), (f) pan-keratin (AE1/AE3, 20×), (g) keratin 19 (20×), and (h) keratin 8/18 (20×). (i) Representative image of spontaneous metastatic lesions. Immunodeficient mice were injected in the left ventricle of the heart with OTBCs86-L1-DsRed cells, and imaging was performed at day 90 after injection. Shown is a representative paraffin-embedded tumor section stained with (j) OCT4 (40×), (k) H&E (40×), (l) H&E magnification from (k), and (m) VIM (40×). Immunofluorescence detection of (n) DsRed-labeled OTBCs (10×), (o) OCT4 (20×), and (p) merged image of DsRed and OCT4 (10×). The square on the left corner shows a detail of DsRed-positive tumor cells expressing OCT4.
Beltran et al. Breast Cancer Research 2011 13:R94 doi:10.1186/bcr3019