| First Author | Sayama K | Year | 1994 |
| Journal | Lab Anim | Volume | 28 |
| Issue | 1 | Pages | 44-9 |
| PubMed ID | 8158968 | Mgi Jnum | J:16782 |
| Mgi Id | MGI:64843 | Doi | 10.1258/002367794781065889 |
| Citation | Sayama K, et al. (1994) Pregnancy dependence of mammary tumours in DDD mice congenic for Mtv-2, DDD/1-Mtv-2/Mtv-2. Lab Anim 28(1):44-9 |
| abstractText | Mammary tumours developed in 110 (95.7%) of 115 DDD/1-Mtv-2/Mtv-2 (DDD/1-Mtv-2) and 24 (47.1%) of 51 DDD/1fDDD/1-Mtv-2 (DDD/1fMtv-2) force-bred female mice during a one-year period. The mean tumour age +/- SE was 220 +/- 7 and 269 +/- 7 days, respectively. These tumours were examined for responsiveness to pregnancies by comparing their growth after transplantation between virgin and breeding recipients. Of 73 tumours from DDD/1-Mtv-2 mice, 9 (12%) were completely pregnancy-dependent (CPD), 3 (4%) pregnancy-dependent (PD), 9 (12%) pregnancy-responsive (PR), and 52 (71%) pregnancy-independent (PI), and of 25 tumours from DDD/1fMtv-2 mice, one (4%) was CPD, one (4%) PR, and 23 (92%) PI. Although most tumours were heterogeneous in morphology and there was no clear relation between morphology and PD properties, most CPD tumours were type P and considered to be connected with mammary plaques. When 9 CPD tumours from DDD/1-Mtv-2 mice were serially transplanted in breeders, 6, 2 and one progressed to lose pregnancy dependence within 3, 8 and 18 generations, respectively. DDD/1-Mtv-2 mice will provide a model for studies on progression of mammary tumours from hormone-dependent to autonomous states. |
