Fig. 4

Metastatic profiles of tumors generated from enriched mammary epithelial cell populations. a Representative bright-field (left panel) and fluorescent (right panel) images of the same lung. Arrowheads indicate metastases (scale bar = 1 mm). b Representative image of hematoxylin and eosin staining of a metastatic lung section. Arrows indicate metastases (scale bar = 1 mm). c Percentage of mice with lung metastases per tumor group. Luminal CD133+ cell tumors were less metastatic than the other tumor groups (two proportion z test; n = number of mice). d Number of metastatic lung foci per tumor group. Luminal CD133+ cell tumors generated fewer metastatic foci than the other tumor groups (Mann–Whitney U test; median values shown). e Quantification of metastasis area per unique metastatic site in serial lung sections. No difference in size of tumor metastasis was detected between the tumor groups (n = number of mice). f Normalized number of circulating tumor cells in mice with luminal CD133+ tumors compared with all other tumor groups. ZsGreen signaling in whole blood isolated from tumor bearing mice was analyzed by fluorescence-activated cell sorting and normalized to no-tumor control signal. Luminal CD133+ tumor-bearing mice had fewer circulating tumor cells. Mice with non-metastatic tumors are represented by green, and those with metastatic tumors are represented by black (unpaired t test; mean values shown; n = number of mice). g Quantification of the number of lung tumor foci per tail vein injection of metastatic luminal CD133+ tumor cells (tumor 1), non-metastatic luminal CD133+ tumor cells (tumor 2), or metastatic luminal CD133− tumor cells (tumors 3 and 4) (unpaired t test; mean values shown; n = number of mice). Data shown in (a)–(e) represent spontaneous metastasis occurring from primary tumors, and data shown in (f) are from non-spontaneous tail vein injection assays. *p < 0.05, **p < 0.01, ***p < 0.0005, ****p < 0.0001