PT  - JOURNAL ARTICLE
AU  - Lawson, J S
AU  - Tran, D D
AU  - Carpenter, E
AU  - Ford, C E
AU  - Rawlinson, W D
AU  - Whitaker, N J
AU  - Delprado, W
TI  - Presence of mouse mammary tumour-like virus gene sequences may be associated with morphology of specific human breast cancer
AID  - 10.1136/jcp.2005.035907
DP  - 2006 Dec 01
TA  - Journal of Clinical Pathology
PG  - 1287--1292
VI  - 59
IP  - 12
4099  - http://jcp.bmj.com/content/59/12/1287.short
4100  - http://jcp.bmj.com/content/59/12/1287.full
SO  - J Clin Pathol2006 Dec 01; 59
AB  - Background: Mouse mammary tumour virus (MMTV) has a proven role in breast carcinogenesis in wild mice and genetically susceptible in-bred mice. MMTV-like env gene sequences, which indicate the presence of a replication-competent MMTV-like virus, have been identified in some human breast cancers, but rarely in normal breast tissues. However, no evidence for a causal role of an MMTV-like virus in human breast cancer has emerged, although there are precedents for associations between specific histological characteristics of human cancers and the presence of oncogenic viruses. Aim: To investigate the possibility of an association between breast cancer and MMTV-like viruses. Methods: Histological characteristics of invasive ductal human breast cancer specimens were compared with archival MMTV-associated mammary tumours from C3H experimental mice. The presence of MMTV-like env DNA sequences in the human breast cancer specimens was determined by polymerase chain reaction and confirmed by Southern hybridisation. Results: MMTV-like env gene sequences were identified in 22 of 59 (37.3%) human breast cancer specimens. Seventeen of 43 (39.5%) invasive ductal carcinoma breast cancer specimens and 4 of 16 (25%) ductal carcinoma in situ specimens had some histological characteristics, which were similar to MMTV-associated mouse mammary tumours. However, these similarities were not associated with the presence or absence of MMTV-like gene sequences in the human breast tumour specimens. A significant (p = 0.05) correlation was found between the grade of the human breast cancer and similarity to the mouse mammary tumours. The lower the grade, the greater the similarity. Conclusion: Some human breast cancer specimens, in which MMTV-like env DNA sequences have been identified, were shown to have histological characteristics (morphology) similar to MMTV-associated mouse mammary tumours. These observations are compatible with, but not conclusive of, an association between the presence of MMTV-like env DNA sequences and some human breast cancers.