Histological grading is a good parameter to stratify tumors according to their biological aggressiveness. The Elston and Ellis grading method in humans, invasive ductal breast carcinomas and other invasive tumors are routinely used. The aims of this study were classification of mammary gland tumors and also application of a human grading method in canine mammary carcinoma. The samples included ...

The development of the mammary gland is unique: the final stages of development occur postnatally at puberty under the influence of hormonal cues. Furthermore, during the life of the female, the mammary gland can undergo many rounds of expansion and proliferation. The mammary gland thus provides an excellent model for studying the ‘stem/progenitor’ cells that allow this repeated expansion and r...

Human endogenous retroviruses (HERVs) account for up to 9% of the human genome and include more than 800 elements related to betaretroviruses. While mouse mammary tumor virus (MMTV) is the accepted etiological agent of mammary tumors in mice, the role of retroviral elements in human breast cancer remains elusive. Here, we performed a comprehensive microarray-based analysis of overall retroviral...

immunize rabbits. The rabbit antiserum was absorbed with normal mouse tissues and tested by gel immunodiffusion with a 2nd group of tumors. The latter were pooled to form 3 distinct groups—strong, weak, and negative reactors. The 3 tumor pools were then used to immunize 3 additional groups of rabbits. The rabbit antisera harvested from the secondary groups were absorbed with spleen homogenate...

Apoptosis is a critical process in normal mammary gland development and the rapid clearance of apoptotic cells prevents tissue injury associated with the release of intracellular antigens from dying cells. Milk fat globule-EGF-factor 8 (Mfge8) is a milk glycoprotein that is abundantly expressed in the mammary gland epithelium and has been shown to facilitate the clearance of apoptotic lymphocyt...

The heterocyclic amines (HCAs) found in cooked meat are procarcinogens that are metabolically activated by N-hydroxylation followed by O-acetylation by the N-acetyltransferases NAT1 and NAT2. Despite the importance of metabolic activation in HCA carcinogenicity and the finding that several HCAs are rodent mammary gland carcinogens, nothing was known about O-acetylation activity in the human mam...

Protein Tyrosine kinase 6 (PTK6/BRK) is overexpressed in the majority of human breast tumors and breast tumor cell lines. It is also expressed in normal epithelial linings of the gastrointestinal tract, skin, and prostate. To date, expression of PTK6 has not been extensively examined in the normal human mammary gland. We detected PTK6 mRNA and protein expression in the immortalized normal MCF-1...

Since the development of strains of mice with variations in the incidence of spontaneous mammary tumors, attempts have been made to demonstrate anatomic or physiologic differences between them that might be etiologically related to tumor formation. We have searched for such a variation in the urinary excretion rates of the so-called sex hormones because of the many observations linking these ag...

increasingly recognized. Breast cancer risk increases with the number of menstrual cycles a women experiences [1] and proliferation occurs in the breast epithelium during the luteal phase, when serum progesterone levels are high [2]. Moreover, postmenopausal women on hormone replacement therapy have increased breast cancer risk when taking combined estrogens and progestins but not with estrogen...

Expression of the mouse mammary tumor virus (MMTV) neu/erbB2 transgene in mice induces mammary tumors. To examine the effect of removing estrogen receptor alpha (ERalpha) signaling on the ability of an MMTV-neu/erbB2 transgene to induce mammary tumors, the neu transgene was expressed in the ERalpha knockout (alphaERKO) mouse, which lacks functional ERalpha. MMTV-neu females that lacked ERalpha ...