Characterization in vitro of luminal and myoepithelial cells isolated from the human mammary gland by cell sorting

The myoepithelial cell compartment of the murine postnatal mammary gland is generated from basal cap cells in the terminal end bud and maintained by self-renewal. Transdifferentiation to the luminal lineage does not normally occur but can be induced by DNA damage, luminal cell death or transplantation into a recipient mammary fat pad. Myoepithelial cells cultivated in vitro can also transdifferentiate towards the luminal lineage. Little is known about the molecular mechanisms and gene regulatory networks underlying this plasticity. Using a transgenic mouse (Tg11.5kb-GFP) that marks cap cells with GFP, we discovered that mature myoepithelial cells placed in culture begin to express GFP within ~24 hrs and later express the Keratin 8 (K8) luminal marker. Cell tracking showed that most K8+ cells arose from GFP+ cells, suggesting that myoepithelial cells de-differentiate towards a progenitor state before changing lineage. Differential gene expression analysis, comparing pure GFP+ cap cells with mature myoepithelial cells, identified multiple transcription factors that iRegulon predicted might regulate the myoepithelial to cap cell transition. Knockout of one of these genes, Regulatory Factor 3 (Rfx3), significantly reduced the population of GFP+ cells and increased differentiation to the K8+ luminal lineage. Rfx3 knockout also reduced mammosphere growth and mammary gland regeneration efficiency in a transplantation assay, but had no effect on proliferation in vitro. Together, these data support a key role for Rfx3 in the stabilization of the mammary basal cell lineages.

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An in vitro long-term culture model for normal human mammary gland: expression and regulation of steroid receptors

Cell and Tissue Research ◽

10.1007/s00441-002-0683-z ◽

2003 ◽

Vol 311 (2) ◽

pp. 217-226 ◽

Cited By ~ 17

Author(s):

Ya-Hua Zhuang ◽

Rauni Saaristo ◽

Timo Ylikomi

Keyword(s):

Mammary Gland ◽

Steroid Receptors ◽

Long Term Culture ◽

Human Mammary Gland ◽

Culture Model ◽

Normal Human ◽

Mammary Gland Expression

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Effect of prolactin on maintenance of prelactating human mammary gland in vitro

In Vitro ◽

10.1007/bf02806027 ◽

1976 ◽

Vol 12 (6) ◽

pp. 467-471 ◽

Cited By ~ 5

Author(s):

B. A. Flaxman ◽

J. Dyckman ◽

A. Feldman

Keyword(s):

Mammary Gland ◽

Human Mammary Gland

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Comparative toxicity assessment of nano- and bulk-phase titanium dioxide particles on the human mammary gland in vitro

Human & Experimental Toxicology ◽

10.1177/0960327120927448 ◽

2020 ◽

Vol 39 (11) ◽

pp. 1475-1486

Author(s):

S Kumar ◽

A Hussain ◽

B Bhushan ◽

G Kaul

Keyword(s):

Titanium Dioxide ◽

Mammary Gland ◽

Epithelial Cells ◽

Mammary Epithelial Cells ◽

Morphological Changes ◽

Reactive Oxygen Species Generation ◽

Mammary Epithelial ◽

Bulk Phase ◽

Human Mammary Gland

There is a major concern that exposure to titanium dioxide (TiO2) nanoparticles (NPs) can have degrading effects on human health as well as mammary gland because of the increased use in numerous sorts of nanotech-based health care and food merchandise. Also, there is a scarcity in NP toxicity studies on the mammary gland; therefore, the aim of the present study was to compare toxicity caused by nano- and bulk-phase TiO2 particles on the human mammary gland in vitro. In comparison to bulk-TiO2 particles, nano-TiO2 cause a significant ( p < 0.05) reduction in viability and increased reactive oxygen species generation in the human mammary epithelial cells after a dose- (1, 2, 5, 10, 20, 50, and 100 µg/mL) and time (6, 12, 24, and 48 h)-dependent exposure. Further, an increase in genotoxicity in the mammary epithelial cells was observed as percent tail DNA and comet area was increased significantly ( p < 0.05) at 12 h of exposure (10 and 100 µg/mL) with nano-TiO2. The scanning electron microscopic examination showed that a 50 µg/mL dose of both nano-TiO2 and bulk-TiO2 particles cause morphological changes and retarded growth pattern of mammary epithelial cells at 12 h. Moreover, a significant ( p < 0.05) increase in apoptosis at 10 µg/mL and necrosis at 50 µg/mL concentrations of nano-TiO2 in comparison to bulk-TiO2 was observed in mammary epithelial cells. Finally, we can conclude that the toxicity caused by nano-TiO2 particles on the human mammary gland cells was comparatively higher than the bulk-TiO2 particles.

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Ultrastructure of myoepithelial cells in human mammary gland tumors

Cancer ◽

10.1002/1097-0142(196806)21:6<1137::aid-cncr2820210615>3.0.co;2-u ◽

1968 ◽

Vol 21 (6) ◽

pp. 1137-1149 ◽

Cited By ~ 71

Author(s):

Tariq M. Murad ◽

Emmerich Von Haam

Keyword(s):

Mammary Gland ◽

Myoepithelial Cells ◽

Mammary Gland Tumors ◽

Human Mammary Gland

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Immunocytochemical identification of proliferating cell types in mouse mammary gland.

Journal of Histochemistry & Cytochemistry ◽

10.1177/38.11.2212615 ◽

1990 ◽

Vol 38 (11) ◽

pp. 1541-1547 ◽

Cited By ~ 25

Author(s):

A Sapino ◽

L Macrì ◽

P Gugliotta ◽

G Bussolati

Keyword(s):

Cell Proliferation ◽

Mammary Gland ◽

Smooth Muscle Actin ◽

Cell Types ◽

Myoepithelial Cells ◽

Mouse Mammary Gland ◽

Staining Procedure ◽

Secretory Cells ◽

Alpha Smooth Muscle Actin

To study cell proliferation in different cell types and segments of the mammary gland, we devised a dual staining procedure, combining nuclear labeling by 5-bromo-2'-deoxy-uridine (BrdU) uptake (revealed by a dark-brown precipitate) and an alternative (red or blue) cytoplasmic labeling by antibodies specific for the differentiation proteins of epithelial, myoepithelial, and secretory cell types. The following markers, revealed by APAAP or beta-galactosidase procedure, were selected: alpha-smooth muscle actin for the myoepithelial cells, keratin (detected by AE1 monoclonal) for the luminal epithelial cells, alpha-lactalbumin and beta-casein for the secretory cells. To follow the full process of organogenesis, the study was conducted in mouse mammary glands from virgin, primed, and lactating animals and from glands cultured in vitro under specific hormone stimulation. Cell proliferation was localized mainly in focal areas (end buds), and mostly corresponded to "null" undifferentiated cells. Estrogen and progestin stimulation induced a relative increase of proliferating differentiated cells of either epithelial or myoepithelial type, localized in ducts and alveolar structures. Prolactin stimulation induced proliferation in secretory cells.

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Luminal MCF-12A and myoepithelial-like Hs 578Bst cells form bilayered acini similar to human breast

10.1101/248765 ◽

2018 ◽

Author(s):

Anne Weber-Ouellette ◽

Mélanie Busby ◽

Isabelle Plante

Keyword(s):

Cell Lines ◽

Smooth Muscle Actin ◽

Three Dimensional ◽

Myoepithelial Cells ◽

Normal Breast ◽

Breast Development ◽

Basal Cells ◽

Culture Model ◽

Luminal And Myoepithelial Cells

2.3.1AbstractThe mammary gland is a complex organ, structured in a ramified epithelium supported by the stroma. The epithelium’s functional unit is the bilayered acinus, made of a layer of luminal cells surrounded by a layer of basal cells mainly composed of myoepithelial cells. The aim of this study was to develop a reproducible and manipulable three-dimensional co-culture model of the bilayered acinus in vitro to study the interactions between the two layers. Two different combinations of cell lines were co-cultured in Matrigel: SCp2 and SCg6 mice cells, or MCF-12A and Hs 578Bst human cell lines. Cell ratios and Matrigel concentration were optimized. The resulting acini were analysed by confocal microscopy using epithelial (E-cadherin) and myoepithelial (α-smooth muscle actin) markers. SCp2 and SCg6 cells formed distinct three-dimensional structures, whereas MCF-12A and Hs 578Bst cells formed some bilayered acini. This in vitro bilayered acini model will allow us to understand the role of interactions between luminal and myoepithelial cells in the normal breast development.

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