Studies of cellular interactions are critical to the understanding of tumorigenesis. Although many studies have demonstrated a monoclonal composition of advanced neoplasms in humans and mice, the clonal composition of smaller, antecedent lesions has been studied less thoroughly. To examine the clonal development of breast cancer, we generated chimeric mammary glands using mouse mammary epitheli...

The expression of a transgene coding for a chimeric molecule, containing the cytoplasmic and transmembrane domains of the beta1-integrin chain and the extracellular domain of the T-cell differentiation antigen CD4, was targeted to the mouse mammary gland by the mouse mammary tumor virus (MMTV) promoter. The chimera does not interact with the extracellular ligands; however, its expression in cul...

The developmental and hormonal regulation of UDP-GlcNA:dolichol phosphate N-acetylglucosamine-1-phosphate transferase (GPT), the enzyme which initiates the biosynthesis of asparagine-linked glycoproteins, was investigated in mouse mammary glands. An anti-peptide antibody raised against the carboxyl-terminal 11 amino acids of mouse GPT, immunoadsorbed GPT activity and recognized a protein of exp...

MicroRNAs (miRNAs) are a class of small non-coding, endogenous regulatory RNAs that function by controlling gene expression at the post-transcriptional level. Using small RNA sequencing and qRT-PCR techniques, we found that the expression of miR-152 was significantly increased during lactation in the mammary glands of dairy cows producing high quality milk compared with that in cows producing l...

1. Insulin is one of the hormones that are essential for successful tissue culture of explants of the mammary glands of pregnant mice. We report here effects of insulin on RNA and protein formation by mammary tissue from pregnant mice and rats incubated in tissue-culture medium 199. 2. The incorporation of [(14)C]adenine over 3hr. into the RNA of explants of the mammary glands of pregnant mice ...

The long terminal repeat (LTR) of mouse mammary tumor virus (MMTV) is known to contain a number of transcriptional regulatory elements, including glucocorticoid response elements. In this study, we showed that a mammary gland/salivary gland enhancer found in the LTR of this virus directs expression of a heterologous promoter to both virgin and lactating mammary glands in transgenic mice. Using ...

Anogenital mammary-like glands may give rise to various pathologic lesions identical to those known in mammary pathology. Tumor occurring in the anogenital region is extremely rare. The histogenetic origin of this tumor is controversial as it is being debated whether such lesions evolve from ectopic breast tissue and most recently, anogenital mammary-like gland. We report a 28-year-old girl who...

The fully differentiated cells of the rat mammary parenchyma, the ductal epithelial, alveolar, and myoepithelial cells, are distinguished by their ultrastructure and by their accumulation of immunocytochemically detectable marker proteins. The different cell types probably develop from primative ductal structures called terminal end buds, which are present in the developing rat mammary glands, ...

An experiment was conducted to study whether piglet growth rate is related to mammary gland size. It involved three primiparous sows and four multiparous sows that were fed ad libitum during the lactation period. The piglets received no creep feed. The weight and teat order of the piglets were recorded. The sows were slaughtered after approximately 4 weeks of lactation (25–28 days). The amounts...

Fermented papaya extracts (FPEs) are obtained by fermentation of papaya by Aspergillus oryzae and yeasts. In this study, we investigated the protective effects of FPEs on mammary gland hyperplasia induced by estrogen and progestogen. Rats were randomly divided into 6 groups, including a control group, an FPE-alone group, a model group, and three FPE treatment groups (each receiving 30, 15, or 5...