Table 2.
Tumor-initiating capacity of mammosphere-forming cells
| Cell type | Tumor incidence | % Tumor incidence | Lung mets |
|---|---|---|---|
| 410.4 MS-1, 10 cells | 1/8 | 12.5 | 7 |
| 410.4 Bulk, 10 cells | 0/8 | 0 | 0 |
| 410.4 MS-1, 50 cells | 3/8 | 37.5 | 0.3 |
| 410.4 Bulk, 50 cells | 1/8 | 12.5 | 0 |
| 410.4 MS-1, 100 cells | 5/8 | 62.5 | 17 |
| 410.4 Bulk, 100 cells | 2/8 | 25 | 0.5 |
| 410.4 MS-1, 500 cells | 7/8 | 87.5 | 3.9 |
| 410.4 Bulk, 500 cells | 5/9 | 55.6 | 3.6 |
| 410.4 Bulk, 5 × 105 | 5/5 | 100 | 28.2 |
MS-1 are mammosphere-derived cells or bulk cells growing under attached culture conditions and injected at the indicated cell doses into the mammary fat pad of syngeneic Balb/cByJ female mice. Tumors palpated twice weekly and degree of metastatic disease determined at necropsy when tumors measured 18 mm in average diameter