Cyclin E activates Cdk2, controls centrosome duplication, and regulates histone gene transcription. Cyclin E is deregulated in cancer and appears as low-molecular-weight (LMW) isoforms that correlate strongly with decreased survival in breast cancer patients. Transgenic mice overexpressing LMW-cyclin E have increased incidence of mammary tumors and distant metastasis when compared with mice tha...

Accurate phosphorylation of tyrosine residues in proteins plays a central role in regulation of cellular function. Although connections between aberrant tyrosine kinase activity and malignancy are well-established, significantly less is known about the roles of protein tyrosine phosphatases (PTPases) in tumorigenesis. We have previously shown that the transmembranal form of PTPase Epsilon (PTPe...

Dose-response relationships for the induction of mammary tumors by a single i.v. injection of N-methyl-N-nitrosourea (MNU) were studied. At 50 days of age, groups of 20 virgin female Sprague-Dawley rats received single doses of 50, 45, 40, 35, 30, 25, 20, 15, or 10 mg MNU per kg body weight; a group of 10 control rats received 0.85% NaCl solution only. Animals were observed for the appearance o...

Epidemiological studies enable us to analyze disease behavior, define risk factors and establish fundamental prognostic criteria, with the purpose of studying different types of diseases. The aim of this study was to determine the epidemiological characteristics of canine mammary tumors diagnosed during the period 2002-2012. The study was based on a retrospective study consisting of 1,917 biops...

C3H and C3H backcross mice were given repeated injections of preparations from strain-specific or strain-related mammary tumors of recent spontaneous origin together with Freund's adjuvant. The effect of the course of injections on spontaneous mammary tumor development was studied. Pre t rea tment with mammary tumor tissue did not lead to a significant reduction in spontaneous mammary tumor inc...

The neu (c-erbB-2, Her-2) protooncogene is amplified and overexpressed in 20-30% of human breast cancers. Although transgenic mouse models have illustrated the role of Neu in the induction of mammary tumors, Neu expression in these models is driven by a strong viral promoter of questionable relevance to the human disease. To ascertain whether expression of activated Neu under the control of the...

Background Mammary gland neoplasms are the most prevalent tumors in dogs, and their treatment is still challenging. A crucial problem in the handling of this type of neoplasm is to obtain primary mammary epithelial cell cultures from the original tumors. The aim of this study was to determine the best conditions to culture primary mammary epithelial cells from several histological types of cani...

Saturable, high-affinity binding sites for 3,5,3'-triiodo-L-thyronine (T3) were identified in isolated nuclei and solubilized chromatin extracts of mammary glands, spontaneous mammary tumors, and liver from C3H/HeN mice. Receptor concentration in whole mammary gland nuclei (254 fmol/mg DNA) was only about one-half that of mouse liver nuclei (536 fmol/mg DNA), but in molecular weight (55,000) an...

Untreated LAF1 mice used in the present series (which are generally considered to be free of the mammary tumor agent) did not develop mammary adenocarcinomas spontaneously. Treatment with methylcholanthrene also failed to produce mammary tumors in this strain in the absence of hormonal stimulation of the mammary tissue (though it did produce leukemia and squamous carcinomas). Continuous stimula...