Monoclonal antibodies have been generated against disrupted mammary tumor viruses isolated from Mus musculus, Mus cervicolor, and Mus cookii. Monoclonal antibodies directed against the M.W. 36,000 external glycoproteins of these viruses demonstrate the presence of multiple epitopes, i.e., distinct antigenic determinants, within these glycoproteins. These epitopes represent type, group, and inte...

Multiple attempts to infect cell lines derived from normal mouse embryos or from normal mouse mammary glands with inocula currently used for experimental transmission of mammary tumor virus have resulted in the abundant produc tion of type C virus particles. Skimmed infectious milk, acellular mammary tumor extracts, and what appeared to be pure mammary tumor virus virions (B particles), which a...

Multiple attempts to infect cell lines derived from normal mouse embryos or from normal mouse mammary glands with inocula currently used for experimental transmission of mammary tumor virus have resulted in the abundant produc tion of type C virus particles. Skimmed infectious milk, acellular mammary tumor extracts, and what appeared to be pure mammary tumor virus virions (B particles), which a...

The expression of tumor-associated antigens on the DBA/2 lymphoma L1210 and three L1210 sublines, each resistant to a different antileukemic agent [guanazole, methylglyoxal-bis(guanylhydrazone), and 4,4-diacetyldiphenylurea-bis(guanylhydrazone)] was investigated by the use of monoclonal hybridoma antibodies. Hybridomas were produced by the fusion of spleen cells from DBA/2 mice immunized with i...

Although the amplified in breast cancer 1 (AIB1) coactivator is amplified and overexpressed in breast cancers, its role in mammary carcinogenesis remains unknown. We demonstrate that during mammary development and tumorigenesis, the elevation of AIB1 level and its nuclear localization correlate with normal and transformed mammary epithelial proliferation, whereas its lower expression and cytopl...

Folic acid supplementation may prevent the development of cancer in normal tissues but may promote the progression of established (pre)neoplastic lesions. However, whether or not folic acid supplementation can promote the progression of established (pre)neoplastic mammary lesions is unknown. This is a critically important issue because breast cancer patients and survivors in North America are l...

stinging nettle (urtica dioica l.,) is a medicinal herb commonly used by humans. the role of reactive oxygen metabolites on cancer etiology is known. there are some studies about the antioxidant effects of urtica dioica (ud) on therapy of some cancer types. this study aimed to investigate the effects of ud on antioxidant enzyme activities and mammary gland cancer induced by in rats-n-methyl-n-n...

Exogenous and dietary estrogens have been associated with modification of breast cancer risk. Mammary cancer model systems can be used to explore interactions between specific transgenes, and hormonal and dietary factors. Transgenic mice bearing the rat wild-type erbB-2 gene were used to study the effects of short-term hormonal exposure [17beta-estradiol (E2) or tamoxifen] or a soy meal diet on...

Insertional mutation of the Int3 gene, a member of the Notch gene family, is frequently associated with primary mouse mammary tumors induced by the mouse mammary tumor virus (MMTV). A major consequence of these mutations is the production of a shortened 2.4-kb tumor specific Int3 RNA transcript that encodes the entire intracellular domain of the Int3 protein. Previous studies have demonstrated ...