Hyperplastic and neoplastic changes in the mammary glands of feral mice free of endogenous mouse mammary tumor virus provirus
Faulkin, L.J.; Mitchell, D.J.; Young, L.J.; Morris, D.W.; Malone, R.W.; Cardiff, R.D.; Gardner, M.B.
Journal of the National Cancer Institute 73(4): 971-982
1984
ISSN/ISBN: 0027-8874 PMID: 6090752 Document Number: 230851
Laboratory colonies of feral mice (Mus musculus domesticus) have been established with specific mouse mammary tumor virus (MuMTV) genotype, including colonies lacking any proviral DNA (ev-) or carrying only a single copy of MuMTV DNA (ev+). No evidence of a decline in reproductive capacity has been observed in the first 8 generations. Both the ev- and ev+ mice showed normal mammary gland development and the development of hyperplastic lesions in the older females. The mice were very resistant to spontaneous or chemically induced mammary tumors. However, the occurrence of 1 mammary tumor in an ev- mouse indicates that mammary neoplasias can occur in the absence of MuMTV DNA. The few tumors that do occur in the ev- mice provide a unique opportunity to study the neoplastic process in the absence of proviral DNA.