Few markers are available to identify the three types of mammary epithelial cells--ductal, alveolar, and myoepithelial--especially in pathological conditions and in cell cultures. We have used antisera to human keratins in immunofluorescence to facilitate the identification of the three mouse mammary epithelial cell types. In frozen tissue sections and primary cell cultures, a rabbit antikerati...

Parotid and submandibular glands in human fetuses at 16, 18 and 24 weeks of gestation were studied by electron microscopy. The salivary glands of the 16 week fetus were composed of primary ducts and terminal buds. The primary duct was double layered and consisted of inner glycogen-rich ductal cells and outer myoepithelial precursor cells. The terminal bud was a cell cluster which consisted of g...

Breast cancer is a genetically and clinically heterogeneous disease, and the contributions of different target cells and different oncogenic mutations to this heterogeneity are not well understood. Here we report that mammary tumors induced by components of the Wnt signaling pathway contain heterogeneous cell types and express early developmental markers, in contrast to tumors induced by other ...

There is increasing evidence that breast and other cancers originate from and are maintained by a small fraction of stem/progenitor cells with self-renewal properties. Recent molecular profiling has identified six major subtypes of breast cancer: basal-like, ErbB2-overexpressing, normal breast epithelial-like, luminal A and B, and claudin-low subtypes. To help understand the relationship among ...

We describe a preclinical model that investigates progression of early-stage ductal carcinoma in situ (DCIS) and report that compromised myoepithelial cell differentiation occurs before transition to invasive disease. Human breast cancer MCF10DCIS.com cells were delivered into the mouse mammary teat by intraductal injection in the absence of surgical manipulations and accompanying wound-healing...

BACKGROUND: Malignant myoepitheliomas of the breast are extremely rare. There has been a limited number of published reports of myoepithelial carcinomas originating from the breast. CASE REPORT: We describe a malignant myoepithelioma of the breast in a 56-year-old woman. Histological examination showed polygonal epithelioid cells and spindle cells with moderate to marked nuclear atypia. Immuno...

The mammary gland is a renewing tissue in which morphogenetic processes and differentiation occur cyclically during the menstrual cycle, pregnancy and lactation. These events have been shown to be dependent upon epithelial-mesenchymal interactions. Studies of the effects of individual factors, their cellular source and their target cell populations in the different developmental stages of the m...

Benign and malignant neoplasm of myoepithelial cells comprise a rare but well-characterized group of tumors in the salivary glands, breasts, and soft tissues. Histopathologically, myoepitheliomas show solid, reticular, trabecular architecture and myxoid or hyaline stroma, and are composed of round/epithelioid or spindle cells. The tumor cells of myoepitheliomas possess the capacity for epitheli...

Women older than 50 years account for 75% of new breast cancer diagnoses, and the majority of these tumors are of a luminal subtype. Although age-associated changes, including endocrine profiles and alterations within the breast microenvironment, increase cancer risk, an understanding of the cellular and molecular mechanisms that underlies these observations is lacking. In this study, we genera...