Table 4. Effect of metformin given from various age on spontaneous tumor development in female SHR mice.
| Parameters | Control-3 | MF-3 | Control-9 | MF-9 | Control-15 | MF-15 |
|---|---|---|---|---|---|---|
| Effective number of micea | 103 | 48 | 97 | 45 | 69 | 33 |
| Age of the death of the 1st TBM | 246 | 300 | 291 | 363 | 458 | 482 |
| Number of TBMb (%) | 57 (55.3%) | 26 (54.2%) | 54 (55.7%) | 30 (66.7%) | 40 (58.0%) | 17 (51.5%) |
| Total number of tumors | 60 | 26 | 57 | 31 | 43 | 18 |
| Number of tumors per TBM | 1.05 | 1.00 | 1.06 | 1.03 | 1.08 | 1.06 |
| Number of malignant TBM (%) | 54 (49.5%) | 26 (54.2%) | 51 (52.6%) | 27 (60.0%) | 37 (53.6%) | 16 (48.5%) |
| Mean life span of TBM, days | 547 ± 22.2 | 590 ± 31.3 (+7.9%) | 562 ± 21.5 | 603 ± 24.4 (+7.3%) | 631 ± 18.9 | 665 ± 34.1 (+5.4%) |
| Localization and type of tumors | ||||||
| Mammary adenocarcinoma | 42 (40.8%) | 23 (47.9%) | 40 (41.2%) | 20 (44.4%) | 27 (39.1%) | 12 (36.4%) |
| Leukemia/lymphoma | 7 (6.8%) | 2 (4.2%) | 6 (6.2%) | 3 (6.7%) | 6 (8.7%) | 3 (9.1%) |
| Ovary: hemangioma granulesa-cell tumor adenocarcinoma |
1 1 1 |
- - 1 |
1 1 1 |
- - 2 |
1 1 1 |
- - - |
| Liver: holangiocarcinoma | 2 | - | 2 | - | 2 | - |
| Lung: adenoma adenocarcinoma |
1 3 |
- - |
1 3 |
2 2 |
1 3 |
1 - |
| Skin: paplilloma fibrosarcoma |
1 - |
- - |
1 - |
1 - |
1 - |
- 1 |
| Soft tissues: sarcoma | - | - | - | - | - | 1 |
| Utery: hemangioma | - | - | - | 1 | - | - |
| Spleen: hemangioma | 1 | - | 1 | - | 1 | - |
a, number of mice surviving the first tumor bearing animal death.
b, TBM, tumor-bearing mice.