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Sample records for lobuloalveolar mammary development

  1. Conditional knockout of fibronectin abrogates mouse mammary gland lobuloalveolar differentiation

    PubMed Central

    Liu, Keyi; Cheng, Le; Flesken-Nikitin, Andrea; Huang, Lynn; Nikitin, Alexander Y.; Pauli, Bendicht U.

    2010-01-01

    Fibronectin (Fn) plays an important part in the branching morphogenesis of salivary gland, lung, and kidney. Here, we examine the effect of the conditional knockout of Fn in the mammary epithelium [FnMEp−/−] on postnatal mammary gland development, using Cre-loxP mediated gene knockout technology. Our data show that Fn deletion causes a moderate retardation in outgrowth and branching of the ductal tree in 5-week old mice. These defects are partially compensated in virgin 16-week old mice. However, mammary glands consisting of Fn-deficient epithelial cells fail to undergo normal lobuloalveolar differentiation during pregnancy. The severity of lobuloalveolar impairment ranged from lobular hypoplasia to aplasia in some cases and was associated with the amount of Fn protein recovered from these glands. Decreased rates of mammary epithelial cell proliferation accounted for delayed ductal outgrowth in virgin and lack of alveologenesis in pregnant FnMEp−/− mice. Concomitant decreased expression of integrin β1 (Itgb1) and lack of autophosphorylation of focal adhesion kinase (Fak) suggest that this pathology might, at least in part, be mediated by disruption of the Fn/Itgb1/Fak signaling pathway. PMID:20624380

  2. Erbb4 Signaling in the Mammary Gland Is Required for Lobuloalveolar Development and Stat5 Activation during Lactation

    PubMed Central

    Jones, Frank E.; Welte, Thomas; Fu, Xin-Yuan; Stern, David F.

    1999-01-01

    Signaling by members of the epidermal growth factor receptor family plays an important role in breast development and breast cancer. Earlier work suggested that one of these receptors, ErbB4, is coupled to unique responses in this tissue. To determine the function of ErbB4 signaling in the normal mouse mammary gland, we inactivated ErbB4 signaling by expressing a COOH terminally deleted dominant-negative allele of ErbB4 (ErbB4ΔIC) as a transgene in the mammary gland. Despite the expression of ErbB4ΔIC from puberty through later stages of mammary development, an ErbB4ΔIC-specific phenotype was not observed until mid-lactation. At 12-d postpartum, lobuloalveoli expressing ErbB4ΔIC protein were condensed and lacked normal lumenal lactation products. In these lobuloalveoli, β-casein mRNA, detected by in situ hybridization, was normal. However, whey acidic protein mRNA was reduced, and α-lactalbumin mRNA was undetectable. Stat5 expression was detected by immunohistochemistry in ErbB4ΔIC-expressing tissue. However, Stat5 was not phosphorylated at Y694 and was, therefore, probably inactive. When expressed transiently in 293T cells, ErbB4 induced phosphorylation of Stat5. This phosphorylation required an intact Stat5 SH2 domain. In summary, our results demonstrate that ErbB4 signaling is necessary for mammary terminal differentiation and Stat5 activation at mid-lactation. PMID:10508857

  3. Cytokine signalling in mammary gland development.

    PubMed

    Watson, Christine J; Oliver, Carrie H; Khaled, Walid T

    2011-03-01

    Mammary gland development occurs in three distinct stages during the lifetime of the female mammal: in embryonic, pubertal and reproductive life. At each of these developmental stages, different signalling molecules induce changes in both the epithelium and the surrounding stroma. However, it is during pregnancy that the most dramatic changes occur, resulting in a massive increase in the number of epithelial cells and in their function. Pregnancy initiates the development of a new epithelial lineage, the alveolar cells, which form the milk-producing lobuloalveolar structures. These cells become redundant at the end of lactation and are removed in an exquisitely controlled process of tissue remodelling coupled with extensive cell death. All of these events require not only steroid hormones but also sequential signalling by cytokines. A recent surprising discovery was that the signalling pathways and cytokines that regulate lineage determination in T helper cells are also involved in mammary gland development during pregnancy.

  4. Expression of novel, putative stem cell markers in prepubertal and lactating mammary glands of bovine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mammary stem cells (MaSC) are essential for growth and maintenance of the mammary epithelium. Two main phases of mammary growth include ductal elongation prior to puberty and lobulo-alveolar growth and development during pregnancy. Some studies have utilized morphological characteristics and retenti...

  5. Induction of mammary gland development in estrogen receptor-alpha knockout mice.

    PubMed

    Bocchinfuso, W P; Lindzey, J K; Hewitt, S C; Clark, J A; Myers, P H; Cooper, R; Korach, K S

    2000-08-01

    Mammary glands from the estrogen receptor-a knockout (alphaERKO) mouse do not undergo ductal morphogenesis or alveolar development. Disrupted ERalpha signaling may result in reduced estrogen-responsive gene products in the mammary gland or reduced mammotropic hormones that contribute to the alphaERKO mammary phenotype. We report that circulating PRL is reduced in the female alphaERKO mouse. Implantation of an age-matched, heterozygous ERalpha pituitary isograft under the renal capsule of 25-day-old or 12-week-old alphaERKO mice increased circulating PRL and progesterone levels, and induced mammary gland development. Grafted alphaERKO mice also possessed hypertrophied corpora lutea demonstrating that PRL is luteotropic in the alphaERKO ovary. By contrast, ovariectomy at the time of pituitary grafting prevented mammary gland development in alphaERKO mice despite elevated PRL levels. Hormone replacement using pellet implants demonstrated that pharmacological doses of estradiol induced limited mammary ductal elongation, and estradiol in combination with progesterone stimulated lobuloalveolar development. PRL alone or in combination with progesterone or estradiol did not induce alphaERKO mammary growth. Estradiol and progesterone are required for the structural development of the alphaERKO mammary gland, and PRL contributes to this development by inducing ovarian progesterone levels. Therefore, the manifestation of the alphaERKO mammary phenotype appears due to the lack of direct estrogen action at the mammary gland and an indirect contributory role of estrogen signaling at the hypothalamic/pituitary axis.

  6. Mammary Gland Development

    PubMed Central

    Macias, Hector

    2012-01-01

    The mammary gland develops through several distinct stages. The first transpires in the embryo as the ectoderm forms a mammary line that resolves into placodes. Regulated by epithelial/mesenchymal interactions, the placodes descend into the underlying mesenchyme and produce the rudimentary ductal structure of the gland present at birth. Subsequent stages of development – pubertal growth, pregnancy, lactation and involution – occur postnatally under the regulation of hormones. Puberty initiates branching morphogenesis, which requires growth hormone and estrogen, as well as IGF1, to create a ductal tree that fills the fat pad. Upon pregnancy the combined actions of progesterone and prolactin generate alveoli, which secrete milk during lactation. Lack of demand for milk at weaning initiates the process of involution whereby the gland is remodeled back to its pre-pregnancy state. These processes require numerous signaling pathways that have distinct regulatory functions at different stages of gland development. Signaling pathways also regulate a specialized subpopulation of mammary stem cells that fuel the dramatic changes in the gland occurring with each pregnancy. Our knowledge of mammary gland development and mammary stem cell biology has significantly contributed to our understanding of breast cancer and has advanced the discovery of therapies to treat this disease. PMID:22844349

  7. Angiotensin II accelerates mammary gland development independently of high blood pressure in pregnancy-associated hypertensive mice.

    PubMed

    Murata, Kazuya; Baasanjav, Altansarnai; Kwon, Chulwon; Hashimoto, Misuzu; Ishida, Junji; Fukamizu, Akiyoshi

    2015-09-01

    Angiotensin II (AngII) is a vasopressor hormone that has critical roles in maintenance of normal blood pressure and pathogenesis of cardiovascular diseases. We previously generated pregnancy-associated hypertensive (PAH) mice by mating female human angiotensinogen transgenic mice with male human renin transgenic mice. PAH mice exhibit hypertension in late pregnancy by overproducing AngII. A recent study demonstrated that angiotensin II type I (AT1) receptor is expressed in mammary epithelial cells and its signaling is critical for mammary gland involution after weaning. However, the role of AngII-AT1 receptor signaling in the development of mammary gland during pregnancy remains unclear. In this study, to investigate the role of AngII-AT1 receptor signaling in mammary gland development during pregnancy, we analyzed the mammary gland of PAH mice. Histological and gene expression analyses revealed that lobuloalveolar development was accelerated with increased milk protein production and lipid accumulation in the mammary gland of PAH mice. Furthermore, AT1 receptor blocker treatment suppressed acceleration of mammary gland development in PAH mice, while the treatment of hydralazine, another antihypertensive drug, did not. These data suggest that AngII-AT1 receptor-induced signaling accelerates mammary gland development during pregnancy through hypertension-independent mechanism.

  8. Targeting expression of a transforming growth factor beta 1 transgene to the pregnant mammary gland inhibits alveolar development and lactation.

    PubMed Central

    Jhappan, C; Geiser, A G; Kordon, E C; Bagheri, D; Hennighausen, L; Roberts, A B; Smith, G H; Merlino, G

    1993-01-01

    Transforming growth factor-beta 1 (TGF-beta 1) possesses highly potent, diverse and often opposing cell-specific activities, and has been implicated in the regulation of a variety of physiologic and developmental processes. To determine the effects of in vivo overexpression of TGF-beta 1 on mammary gland function, transgenic mice were generated harboring a fusion gene consisting of the porcine TGF-beta 1 cDNA placed under the control of regulatory elements of the pregnancy-responsive mouse whey-acidic protein (WAP) gene. Females from two of four transgenic lines were unable to lactate due to inhibition of the formation of lobuloalveolar structures and suppression of production of endogenous milk protein. In contrast, ductal development of the mammary glands was not overtly impaired. There was a complete concordance in transgenic mice between manifestation of the lactation-deficient phenotype and expression of RNA from the WAP/TGF-beta 1 transgene, which was present at low levels in the virgin gland, but was greatly induced at mid-pregnancy. TGF-beta 1 was localized to numerous alveoli and to the periductal extracellular matrix in the mammary gland of transgenic females late in pregnancy by immunohistochemical analysis. Glands reconstituted from cultured transgenic mammary epithelial cells duplicated the inhibition of lobuloalveolar development observed in situ in the mammary glands of pregnant transgenic mice. Results from this transgenic model strongly support the hypothesis that TGF-beta 1 plays an important in vivo role in regulating the development and function of the mammary gland. Images PMID:8491177

  9. Mammary Gland Specific Knockdown of the Physiological Surge in Cx26 during Lactation Retains Normal Mammary Gland Development and Function

    PubMed Central

    Stewart, Michael K. G.; Plante, Isabelle; Bechberger, John F.; Naus, Christian C.; Laird, Dale W.

    2014-01-01

    Connexin26 (Cx26) is the major Cx protein expressed in the human mammary gland and is up-regulated during pregnancy while remaining elevated throughout lactation. It is currently unknown if patients with loss-of-function Cx26 mutations that result in hearing loss and skin diseases have a greater susceptibility to impaired breast development. To investigate if Cx26 plays a critical role in mammary gland development and differentiation, a novel Cx26 conditional knockout mouse model was generated by crossing Cx26fl/fl mice with mice expressing Cre under the β-Lactoglobulin promoter. Conditional knockdown of Cx26 from the mammary gland resulted in a dramatic reduction in detectable gap junction plaques confirmed by a significant ∼65-70% reduction in Cx26 mRNA and protein throughout parturition and lactation. Interestingly, this reduction was accompanied by a decrease in mammary gland Cx30 gap junction plaques at parturition, while no change was observed for Cx32 or Cx43. Whole mount, histological and immunofluorescent assessment of breast tissue revealed comparatively normal lobuloalveolar development following pregnancy in the conditionally knockdown mice compared to control mice. In addition, glands from genetically-modified mice were capable of producing milk proteins that were evident in the lumen of alveoli and ducts at similar levels as controls, suggesting normal gland function. Together, our results suggest that low levels of Cx26 expression throughout pregnancy and lactation, and not the physiological surge in Cx26, is sufficient for normal gland development and function. PMID:24988191

  10. Caveolin-1-deficient Mice Show Accelerated Mammary Gland Development During Pregnancy, Premature Lactation, and Hyperactivation of the Jak-2/STAT5a Signaling Cascade

    PubMed Central

    Park, David S.; Lee, Hyangkyu; Frank, Philippe G.; Razani, Babak; Nguyen, Andrew V.; Parlow, Albert F.; Russell, Robert G.; Hulit, James; Pestell, Richard G.; Lisanti, Michael P.

    2002-01-01

    It is well established that mammary gland development and lactation are tightly controlled by prolactin signaling. Binding of prolactin to its cognate receptor (Prl-R) leads to activation of the Jak-2 tyrosine kinase and the recruitment/tyrosine phosphorylation of STAT5a. However, the mechanisms for attenuating the Prl-R/Jak-2/STAT5a signaling cascade are just now being elucidated. Here, we present evidence that caveolin-1 functions as a novel suppressor of cytokine signaling in the mammary gland, akin to the SOCS family of proteins. Specifically, we show that caveolin-1 expression blocks prolactin-induced activation of a STAT5a-responsive luciferase reporter in mammary epithelial cells. Furthermore, caveolin-1 expression inhibited prolactin-induced STAT5a tyrosine phosphorylation and DNA binding activity, suggesting that caveolin-1 may negatively regulate the Jak-2 tyrosine kinase. Because the caveolin-scaffolding domain bears a striking resemblance to the SOCS pseudosubstrate domain, we examined whether Jak-2 associates with caveolin-1. In accordance with this homology, we demonstrate that Jak-2 cofractionates and coimmunoprecipitates with caveolin-1. We next tested the in vivo relevance of these findings using female Cav-1 (−/−) null mice. If caveolin-1 normally functions as a suppressor of cytokine signaling in the mammary gland, then Cav-1 null mice should show premature development of the lobuloalveolar compartment because of hyperactivation of the prolactin signaling cascade via disinhibition of Jak-2. In accordance with this prediction, Cav-1 null mice show accelerated development of the lobuloalveolar compartment, premature milk production, and hyperphosphorylation of STAT5a (pY694) at its Jak-2 phosphorylation site. In addition, the Ras-p42/44 MAPK cascade is hyper-activated. Because a similar premature lactation phenotype is observed in SOCS1 (−/−) null mice, we conclude that caveolin-1 is a novel suppressor of cytokine signaling. PMID:12388746

  11. Dietary genistein stimulates mammary development in gilts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The possible role of the phytoestrogen, genistein, on prepubertal development of mammary glands, hormonal status and bone resorption was investigated in gilts. Forty-five gilts were fed a control diet containing soya (CTLS, n = 15), a control diet without soya (CTL0, n = 15) or the CTLS diet supplem...

  12. Comparative aspects of mammary gland development and homeostasis.

    PubMed

    Capuco, Anthony V; Ellis, Steven E

    2013-01-01

    Mammary glands are crucial to the reproductive strategy of mammals, and the milk of domesticated ruminants serves as an important source of nutrients for the human population. The majority of mammary gland development occurs postnatally, and the mammary gland undergoes cyclical periods of growth, differentiation, lactation, and regression that are coordinated to provide nutrients for offspring or are driven by strategies to manage reproduction and milk production of domesticated species. Growth and maintenance of the mammary epithelium depends on the function of mammary stem cells and progenitor cells. In this review, we provide an overview of postnatal mammary gland development, cyclical phases of mammary gland regression (regression during lactation and between successive lactations), and mammary stem cells and progenitor cells. Where possible, these processes are related to animal production and compared across species, particularly bovine, porcine, murine, and human.

  13. Stromal Effects on Mammary Gland Development and Breast Cancer

    NASA Astrophysics Data System (ADS)

    Wiseman, Bryony S.; Werb, Zena

    2002-05-01

    Breast cancer manifests itself in the mammary epithelium, yet there is a growing recognition that mammary stromal cells also play an important role in tumorigenesis. During its developmental cycle, the mammary gland displays many of the properties associated with breast cancer, and many of the stromal factors necessary for mammary development also promote or protect against breast cancer. Here we review our present knowledge of the specific factors and cell types that contribute to epithelial-stromal crosstalk during mammary development. To find cures for diseases like breast cancer that rely on epithelial-stromal crosstalk, we must understand how these different cell types communicate with each other.

  14. Positional variations in mammary gland development and cancer.

    PubMed

    Veltmaat, Jacqueline M; Ramsdell, Ann F; Sterneck, Esta

    2013-06-01

    Most mammals develop their mammary glands in pairs of which the two counterparts are symmetrically displaced away from the ventral midline. Based on this symmetry and the same functional outcome as a milk-producing organ, the mammary glands are easily presumed to be mere copies of one another. Based on our analysis of published data with inclusion of new results related to mammary development and pathology in mice, we argue that this presumption is incorrect: Between and within pairs, mammary glands differ from one another, and tumor incidence and biology depend on the position along the anterior-posterior and the left-right axis as well. This insight has implications for experimental designs with mouse models and for data extrapolation between mammary glands within and between species. We suggest that improved documentation of location-specific mammary gland features will lead to more insights into the molecular mechanisms of mammary gland development and cancer biology in both mice and humans.

  15. Aryl hydrocarbon receptor (AhR) activation during pregnancy, and in adult nulliparous mice, delays the subsequent development of DMBA-induced mammary tumors

    PubMed Central

    Wang, Tao; Gavin, Heather M.; Arlt, Volker M.; Lawrence, B. Paige; Fenton, Suzanne E.; Medina, Daniel; Vorderstrasse, Beth A.

    2010-01-01

    TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin), the prototypic ligand for the aryl hydrocarbon receptor (AhR), promotes tumor formation in some model systems. However with regard to breast cancer, epidemiological and animal studies are inconclusive as to whether exposure increases tumor incidence or may instead be protective. We have previously reported that mice exposed to TCDD during pregnancy have impaired differentiation of mammary tissue, including decreased branching and poor development of lobuloalveolar structures. Because normal pregnancy-induced mammary differentiation may protect against subsequent neoplastic transformation, we hypothesized that TCDD-treated mice would be more susceptible to chemical carcinogenesis after parturition. To test this, mice were treated with TCDD or vehicle during pregnancy. Four weeks later, DMBA (7,12-dimethylbenz[a]anthracene) was administered to induce mammary tumor formation. Contrary to our hypothesis, TCDD-exposed parous mice showed a four-week delay in tumor formation relative to controls, and had a lower tumor incidence throughout the 27-week time course. The same results were obtained in nulliparous mice given TCDD and DMBA on the same schedule. We next addressed whether the delayed tumor incidence was a reflection of decreased tumor initiation, by testing the formation of DMBA-DNA adducts and preneoplastic lesions, induction of cytochrome P450s, and cell proliferation. None of these markers of tumor initiation differed between vehicle- and TCDD-treated animals. The expression of CXCL12 and CXCR4 was also measured to address their possible role in tumorigenesis. Taken together, our results suggest that AhR activation by TCDD slows the promotion of preneoplastic lesions to overt mammary tumors. PMID:20521247

  16. Mammary Development and Breast Cancer: A Wnt Perspective

    PubMed Central

    Yu, Qing Cissy; Verheyen, Esther M.; Zeng, Yi Arial

    2016-01-01

    The Wnt pathway has emerged as a key signaling cascade participating in mammary organogenesis and breast oncogenesis. In this review, we will summarize the current knowledge of how the pathway regulates stem cells and normal development of the mammary gland, and discuss how its various components contribute to breast carcinoma pathology. PMID:27420097

  17. Mammary Development and Breast Cancer: A Wnt Perspective.

    PubMed

    Yu, Qing Cissy; Verheyen, Esther M; Zeng, Yi Arial

    2016-01-01

    The Wnt pathway has emerged as a key signaling cascade participating in mammary organogenesis and breast oncogenesis. In this review, we will summarize the current knowledge of how the pathway regulates stem cells and normal development of the mammary gland, and discuss how its various components contribute to breast carcinoma pathology. PMID:27420097

  18. Pim-1 kinase expression during murine mammary development

    SciTech Connect

    Gapter, Leslie A.; Magnuson, Nancy S.; Ng, Ka-yun; Hosick, Howard L. . E-mail: hosick@wsu.edu

    2006-07-07

    Pim-1 kinase phosphorylates substrates whose activities are linked to proliferation, survival, differentiation, and apoptosis. Although pim-1 is induced by hormones and cytokines, the hormonal control and contribution of Pim-1 to mammary gland development have not been evaluated. We examined Pim-1 expression in mammary cell lines, investigated whether Pim-1 levels could be altered in breast epithelia by mammogenic hormones, and evaluated Pim-1 expression during mammary development. We found that Pim-1 was elevated in most mammary carcinoma cell lines and progesterone increased Pim-1 protein to some extent in non-tumorigenic mammary epithelia. Pim-1 expression in situ was consistent with the documented profile of progesterone activity in mouse mammary glands. Pim-1 nuclear localization correlated with cytoplasmic distribution for its substrate, p21{sup CIP/Waf1}, and we found that Pim-1 and p21 associate in vitro. Our results suggest that Pim-1 expression may be regulated by progesterone during mammary development and Pim-1 associates with p21 in mammary epithelial cells.

  19. The role of neutralizing antibodies for mouse mammary tumor virus transmission and mammary cancer development

    NASA Astrophysics Data System (ADS)

    Finke, Daniela; Luther, Sanjiv A.; Acha-Orbea, Hans

    2003-01-01

    Mouse mammary tumor virus (MMTV) infection establishes chronic germinal centers and a lifelong neutralizing Ab response. We show that removal of the draining lymph node after establishment of the germinal center reaction led to complete loss of neutralizing Abs despite comparable infection levels in peripheral lymphocytes. Importantly, in the absence of neutralization, only the exocrine organs mammary gland, salivary gland, pancreas, and skin showed strikingly increased infection, resulting in accelerated mammary tumor development. Induction of stronger neutralization did not influence chronic infection levels of peripheral lymphoid organs but strongly inhibited mammary gland infection and virus transmission to the next generation. Taken together, we provide evidence that a tight equilibrium in virus neutralization allows limited infection of exocrine organs and controls cancer development in susceptible mouse strains. These experiments show that a strong neutralizing Ab response induced after infection is not able to control lymphoid MMTV infection. Strong neutralization, however, is capable of blocking amplification of mammary gland infection, tumor development, and virus transmission to the next generation. The results also indicate a role of neutralization in natural resistance to MMTV infection.

  20. Postnatal and postpartal morphology of the mammary gland in nude mice.

    PubMed

    Militzer, K; Schwalenstöcker, H

    1996-08-01

    The object of this work was to compare the postnatal and postpartal morphology of the mammary gland of nu/nu with that of nu/(+)-mice. All studies were carried out on groups of female (athymic) nude mice with NMRI genetic background, their nu/(+)-siblings and dams. The various age groups (3, 21, 40, 55, 70 and 120 days) each consisted of 6 nu/nu- and 6 heterozygous nu/(+)-mice respectively. The morphological examination of the mammary gland tissue were made on histological sections and whole mounts. Body weights, total areas of the mammary glands and the number of the terminal end buds were compared. The mammary gland of the athymic nude mouse exhibited no essential morphological differences from the normal developing mammary gland of the hairy euthymic nu/(+)-animal. The area of the mammary gland increased with increasing body weight. Both collectives of mice differed only in their rate of mammary gland development. As a result, the terminal end buds appeared numerously as growth points of mammary gland in nu/(+)-animals as early as the 21st day of life. The athymic nude mice showed a maximum only on the 40th day of life and a lower degree of density and differentiation of specific mammary gland structures (lateral buds, lobulo-alveolar glandular endings) until the 70th day of life. The mammary gland of 120-day-old animals and dams of both animal groups reached the same state of maturity. Thus it is not the rate of development of the dam, but other, yet unidentified factors, which determine, if successful breeding of nude mice with homozygous parents is possible.

  1. Stem cells and the developing mammary gland.

    PubMed

    Makarem, Maisam; Spike, Benjamin T; Dravis, Christopher; Kannan, Nagarajan; Wahl, Geoffrey M; Eaves, Connie J

    2013-06-01

    The mammary gland undergoes dynamic changes throughout life. In the mouse, these begin with initial morphogenesis of the gland in the mid-gestation embryo followed by hormonally regulated changes during puberty and later in adulthood. The adult mammary gland contains a hierarchy of cell types with varying potentials for self-maintenance and differentiation. These include cells able to produce complete, functional mammary glands in vivo and that contain daughter cells with the same remarkable regenerative potential, as well as cells with more limited clonogenic activity in vitro. Here we review how applying in vitro and in vivo methods for quantifying these cells in adult mammary tissue to fetal mammary cells has enabled the first cells fulfilling the functional criteria of transplantable, isolated mammary stem cells to be identified a few days before birth. Thereafter, the number of these cells increases rapidly. Populations containing these fetal stem cells display growth and gene expression programs that differ from their adult counterparts but share signatures characteristic of certain types of breast cancer. Such observations reinforce growing evidence of important differences between tissue-specific fetal and adult cells with stem cell properties and emphasize the merits of investigating their molecular basis.

  2. Hippo pathway in mammary gland development and breast cancer.

    PubMed

    Shi, Peiguo; Feng, Jing; Chen, Ceshi

    2015-01-01

    Accumulated evidence suggests that the Hippo signaling pathway plays crucial roles in mammary gland development and breast cancer. Key components of the Hippo pathway regulate breast epithelial cell proliferation, migration, invasion, and stemness. Additionally, the Hippo pathway regulates breast tumor growth, metastasis, and drug resistance. It is expected that the Hippo pathway will provide novel therapeutic targets for breast cancer. This review will discuss and summarize the roles of several core components of the Hippo pathway in mammary gland development and breast cancer.

  3. The epigenetic landscape of mammary gland development and functional differentiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most of the development and functional differentiation in the mammary gland occur after birth. Epigenetics is defined as the stable alterations in gene expression potential that arise during development and proliferation. Epigenetic changes are mediated at the biochemical level by the chromatin conf...

  4. INDUCTION OF MAMMARY GLAND DEVELOPMENT IN ESTROGEN RECEPTOR-ALPHA KNOCKOUT MICE

    EPA Science Inventory

    Mammary glands from the estrogen receptor knockout ( ERKO) mouse do not undergo ductal morphogenesis or alveolar development. Disrupted Er signaling may result in reduced estrogen-responsive gene products in the mammary gland or reduced mammotropic hormones that contribute t...

  5. The role of activin in mammary gland development and oncogenesis.

    PubMed

    Dunphy, Karen A; Schneyer, Alan L; Hagen, Mary J; Jerry, D Joseph

    2011-06-01

    TGFβ contributes to mammary gland development and has paradoxical roles in breast cancer because it has both tumor suppressor and tumor promoter activity. Another member of the TGFβ superfamily, activin, also has roles in the developing mammary gland, but these functions, and the role of activin in breast cancer, are not well characterized. TGFβ and activin share the same intracellular signaling pathways, but divergence in their signaling pathways are suggested. The purpose of this review is to compare the spatial and temporal expression of TGFβ and activin during mammary gland development, with consideration given to their functions during each developmental period. We also review the contributions of TGFβ and activin to breast cancer resistance and susceptibility. Finally, we consider the systemic contributions of activin in regulating obesity and diabetes; and the impact this regulation has on breast cancer. Elevated levels of activin in serum during pregnancy and its influence on pregnancy associated breast cancer are also considered. We conclude that evidence demonstrates that activin has tumor suppressing potential, without definitive indication of tumor promoting activity in the mammary gland, making it a good target for development of therapeutics.

  6. MAMMARY GLAND DEVELOPMENT: EARLY LIFE EFFECTS FROM THE ENVIRONMENT

    EPA Science Inventory

    Mammary Gland Development: Early Life Effects from the Environment

    S.E. Fenton. Reproductive Toxicology Division, National Health and Environmental Effects Laboratory, ORD, U.S. EPA, Research Triangle Park, NC 27711.

    As signs of precocious puberty in girls reach ...

  7. FEEDING GENISTEIN TO PREPUBERTAL GILTS STIMULATES THEIR MAMMARY DEVELOPMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The possible role of dietary genistein on mammary development of prepubertal gilts was investigated. Forty-five gilts were fed one of three diets from 90 d of age until slaughter (day 183 ± 1). Diets were: without soya (CTL0, n=15); soya-based commercial (CTLS, n=15); and soya-based commercial with ...

  8. RUNX2 in mammary gland development and breast cancer.

    PubMed

    Ferrari, Nicola; McDonald, Laura; Morris, Joanna S; Cameron, Ewan R; Blyth, Karen

    2013-06-01

    Runx2 is best known as an essential factor in osteoblast differentiation and bone development but, like many other transcription factors involved in development, is known to operate over a much wider tissue range. Our understanding of these other aspects of Runx2 function is still at a relatively early stage and the importance of its role in cell fate decisions and lineage maintenance in non-osseous tissues is only beginning to emerge. One such tissue is the mammary gland, where Runx2 is known to be expressed and participate in the regulation of mammary specific genes. Furthermore, differential and temporal expression of this gene is observed during mammary epithelial differentiation in vivo, strongly indicative of an important functional role. Although the precise nature of that role remains elusive, preliminary evidence hints at possible involvement in the regulation of mammary stem and/or progenitor cells. As with many genes important in regulating cell fate, RUNX2 has also been linked to metastatic cancer where in some established breast cell lines, retention of expression is associated with a more invasive phenotype. More recently, expression analysis has been extended to primary breast cancers where high levels of RUNX2 align with a specific subtype of the disease. That RUNX2 expression correlates with the so called "Triple Negative" subtype is particularly interesting given the known cross talk between Runx2 and estrogen receptor signaling pathways. This review summaries our current understanding of Runx2 in mammary gland development and cancer, and postulates a role that may link both these processes.

  9. Amphiregulin: role in mammary gland development and breast cancer.

    PubMed

    McBryan, Jean; Howlin, Jillian; Napoletano, Silvia; Martin, Finian

    2008-06-01

    Extensive epithelial cell proliferation underlies the ductal morphogenesis of puberty that generates the mammary tree that will eventually fill the fat pad. This estrogen-dependent process is believed to be essentially dependent on locally produced growth factors that act in a paracrine fashion. EGF-like growth factor ligands, acting through EGF receptors are some of the principal promoters of pubertal ductal morphogenesis. Amphiregulin is the most abundant EGF-like growth factor in the pubertal mammary gland. Its gene is transcriptionally regulated by ERalpha, and recent evidence identifies it as a key mediator of the estrogen-driven epithelial cell proliferation of puberty: The pubertal deficiency in mammary gland ductal morphogenesis in ERalpha, amphiregulin, and EGFR knockout mice phenocopy each other. As a prognostic indicator in human breast cancer, amphiregulin indicates an outcome identical to that predicted by ERalpha presence. Despite this, a range of studies both on preneoplastic human breast tissue and on cell culture based models of breast cancer, suggest a possibly significant role for amphiregulin in driving human breast cancer progression. Here we summarise our current understanding of amphiregulin's contribution to mammary gland development and breast cancer progression.

  10. Mammary gland development: cell fate specification, stem cells and the microenvironment.

    PubMed

    Inman, Jamie L; Robertson, Claire; Mott, Joni D; Bissell, Mina J

    2015-03-15

    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 renewal. In this Review, we provide an overview of the different cell types that constitute the mammary gland, and discuss how these cell types arise and differentiate. As cellular differentiation cannot occur without proper signals, we also describe how the tissue microenvironment influences mammary gland development.

  11. Diet-induced obesity disrupts ductal development in the mammary glands of nonpregnant mice.

    PubMed

    Kamikawa, Akihiro; Ichii, Osamu; Yamaji, Daisuke; Imao, Takeshi; Suzuki, Chiharu; Okamatsu-Ogura, Yuko; Terao, Akira; Kon, Yasuhiro; Kimura, Kazuhiro

    2009-05-01

    Mammary glands develop postnatally in response to the hypothalamic-pituitary-gonadal axis. Obesity-induced changes in the local environment, however, retard mammary gland development during late pregnancy and lactation. To clarify the effects of obesity on fundamental duct development, we compared the mammary glands of nulliparous nonpregnant obese mice fed a high-fat diet with those of lean mice fed a normal diet. Obese mice had enlarged mammary glands, reflecting fat pad size, whereas the ducts in obese mice showed a less dense distribution with less frequent branching. Additionally, the ducts were surrounded by thick collagen layers, and were incompletely lined with myoepithelium. Because leptin receptors were localized in the epithelium region and leptin that was highly expressed in the obese glands suppressed mammary epithelial cell proliferation in vitro, the present results suggest that obesity disrupts mammary ductal development, possibly by remodeling the mammary microenvironment and promoting the expression of such paracrine factors as leptin.

  12. Primary Cilia Regulate Branching Morphogenesis During Mammary Gland Development

    PubMed Central

    McDermott, Kimberly M.; Liu, Bob Y.; Tlsty, Thea D.; Pazour, Gregory J.

    2010-01-01

    Summary During mammary gland development an epithelial bud undergoes branching morphogenesis to expand into a continuous tree-like network of branched ducts [1]. The process involves multiple cell types that are coordinated by hormones and growth factors coupled with signaling events including Wnt and Hedgehog [2-5]. Primary cilia play key roles in the development of many organs by coordinating extracellular signaling (Wnt, Hedgehog) with cellular physiology [6-8]. During mammary development, we find cilia on luminal epithelial, myoepithelial and stromal cells during early branching morphogenesis when epithelial ducts extend into the fat pad and undergo branching morphogenesis. When branching is complete, cilia disappear from luminal epithelial cells but remain on myoepithelial and stromal cells. Ciliary dysfunction caused by intraflagellar transport (IFT) defects results in branching defects. These include decreased ductal extension and decreased secondary and tertiary branching along with reduced lobular-alveolar development during pregnancy and lactation. We find increased canonical Wnt and decreased Hedgehog signaling in the mutant glands, which is consistent with the role of cilia in regulating these pathways [6-11]. In mammary gland and other organs, increased canonical Wnt [12-14] and decreased Hedgehog [15, 16] signaling decreases branching morphogenesis suggesting that Wnt and Hedgehog signaling connect ciliary dysfunction to branching defects. PMID:20381354

  13. Serotoninergic and Circadian Systems: Driving Mammary Gland Development and Function.

    PubMed

    Suárez-Trujillo, Aridany; Casey, Theresa M

    2016-01-01

    Since lactation is one of the most metabolically demanding states in adult female mammals, beautifully complex regulatory mechanisms are in place to time lactation to begin after birth and cease when the neonate is weaned. Lactation is regulated by numerous different homeorhetic factors, all of them tightly coordinated with the demands of milk production. Emerging evidence support that among these factors are the serotonergic and circadian clock systems. Here we review the serotoninergic and circadian clock systems and their roles in the regulation of mammary gland development and lactation physiology. We conclude by presenting our hypothesis that these two systems interact to accommodate the metabolic demands of lactation and thus adaptive changes in these systems occur to maintain mammary and systemic homeostasis through the reproductive cycles of female mammals. PMID:27471474

  14. Serotoninergic and Circadian Systems: Driving Mammary Gland Development and Function

    PubMed Central

    Suárez-Trujillo, Aridany; Casey, Theresa M.

    2016-01-01

    Since lactation is one of the most metabolically demanding states in adult female mammals, beautifully complex regulatory mechanisms are in place to time lactation to begin after birth and cease when the neonate is weaned. Lactation is regulated by numerous different homeorhetic factors, all of them tightly coordinated with the demands of milk production. Emerging evidence support that among these factors are the serotonergic and circadian clock systems. Here we review the serotoninergic and circadian clock systems and their roles in the regulation of mammary gland development and lactation physiology. We conclude by presenting our hypothesis that these two systems interact to accommodate the metabolic demands of lactation and thus adaptive changes in these systems occur to maintain mammary and systemic homeostasis through the reproductive cycles of female mammals. PMID:27471474

  15. Neuregulin 3 and erbb signalling networks in embryonic mammary gland development.

    PubMed

    Kogata, Naoko; Zvelebil, Marketa; Howard, Beatrice A

    2013-06-01

    We review the role of Neuregulin 3 (Nrg3) and Erbb receptor signalling in embryonic mammary gland development. Neuregulins are growth factors that bind and activate its cognate Erbb receptor tyrosine kinases, which form a signalling network with established roles in breast development and breast cancer. Studies have shown that Nrg3 expression profoundly impacts early stages of embryonic mammary development. Network analysis shows how Nrg/Erbb signals could integrate with other major regulators of embryonic mammary development to elicit the morphogenetic processes and cell fate decisions that occur as the mammary lineage is established.

  16. Integrin β4 regulation of PTHrP underlies its contribution to mammary gland development.

    PubMed

    Li, Jiarong; Sun, Huayan; Feltri, M Laura; Mercurio, Arthur M

    2015-11-15

    The integrin α6β4 (referred to as β4) is expressed in epithelial cells where it functions as a laminin receptor. Although in vitro studies have implicated β4 in the biology of mammary epithelial cells, its contribution to mammary gland development has not been settled. To address this problem, we generated and analyzed itgb4(flox/flox)MMTV-Cre(-) and itgb4(flox/flox)MMTV-Cre(+) mice. The salient features of embryonic mammary tissue from itgb4(flox/flox)MMTV-Cre(+) mice were significantly smaller mammary buds and increased apoptosis in the surrounding mesenchyme. Also, compared to control glands, the itgb4-deleted mammary buds lacked expression of the progenitor cell marker CK14 and they were unable to generate mammary glands upon transplantation into cleared fat pads of recipient mice. Analysis of mammary glands at puberty and during pregnancy revealed that itgb4-diminished mammary tissue was unable to elongate and undergo branching morphogenesis. Micro-dissection of epithelial cells in the mammary bud and of the surrounding mesenchyme revealed that loss of β4 resulted in a significant decrease in the expression of parathyroid hormone related protein (PTHrP) in epithelial cells and of target genes of the PTHrP receptor in mesenchymal cells. Given that the phenotype of the itgb4-deleted mammary tissue mimicked that of the PTHrP knockout, we hypothesized that β4 contributes to mammary gland development by sustaining PTHrP expression and enabling PTHrP signaling. Indeed, the inability of itgb4-deleted mammary buds to elongate was rescued by exogenous PTHrP. These data implicate a critical role for the β4 integrin in mammary gland development and provide a mechanism for this role.

  17. Non-coding RNAs in Mammary Gland Development and Disease.

    PubMed

    Sandhu, Gurveen K; Milevskiy, Michael J G; Wilson, Wesley; Shewan, Annette M; Brown, Melissa A

    2016-01-01

    Non-coding RNAs (ncRNAs) are untranslated RNA molecules that function to regulate the expression of numerous genes and associated biochemical pathways and cellular functions. NcRNAs include small interfering RNAs (siRNAs), microRNAs (miRNAs), PIWI-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs) and long non-coding RNAs (lncRNAs). They participate in the regulation of all developmental processes and are frequently aberrantly expressed or functionally defective in disease. This Chapter will focus on the role of ncRNAs, in particular miRNAs and lncRNAs, in mammary gland development and disease.

  18. Non-coding RNAs in Mammary Gland Development and Disease.

    PubMed

    Sandhu, Gurveen K; Milevskiy, Michael J G; Wilson, Wesley; Shewan, Annette M; Brown, Melissa A

    2016-01-01

    Non-coding RNAs (ncRNAs) are untranslated RNA molecules that function to regulate the expression of numerous genes and associated biochemical pathways and cellular functions. NcRNAs include small interfering RNAs (siRNAs), microRNAs (miRNAs), PIWI-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs) and long non-coding RNAs (lncRNAs). They participate in the regulation of all developmental processes and are frequently aberrantly expressed or functionally defective in disease. This Chapter will focus on the role of ncRNAs, in particular miRNAs and lncRNAs, in mammary gland development and disease. PMID:26659490

  19. β-casein gene expression by in vitro cultured bovine mammary epithelial cells derived from developing mammary glands.

    PubMed

    Monzani, P S; Bressan, F F; Mesquita, L G; Sangalli, J R; Meirelles, F V

    2011-04-12

    Epithelial cells from mammary gland tissue that are cultured in vitro are able to maintain specific functions of this gland, such as cellular differentiation and milk protein synthesis. These characteristics make these cells a useful model to study mammary gland physiology, development and differentiation; they can also be used for production of exogenous proteins of pharmaceutical interest. Bovine mammary epithelial cells were cultured in vitro after isolation from mammary gland tissue of animals at different stages of development. The cells were plated on Petri dishes and isolated from fibroblasts using saline/EDTA treatment, followed by trypsinization. Cells isolated on plastic were capable of differentiating into alveolus-like structures; however, only cells derived from non-pregnant and non-lactating animals expressed β-casein. Real-time qPCR and epifluorescence microscopy analyses revealed that alveolus-like structures were competent at expressing Emerald green fluorescent protein (EmGFP) driven by the β-casein promoter, independent of β-casein expression.

  20. The biology of zinc transport in mammary epithelial cells: implications for mammary gland development, lactation, and involution.

    PubMed

    McCormick, Nicholas H; Hennigar, Stephen R; Kiselyov, Kirill; Kelleher, Shannon L

    2014-03-01

    Zinc plays a critical role in a vast array of cellular functions including gene transcription, protein translation, cell proliferation, differentiation, bioenergetics, and programmed cell death. The mammary gland depends upon tight coordination of these processes during development and reproduction for optimal expansion, differentiation, and involution. For example, zinc is required for activation of matrix metalloproteinases, intracellular signaling cascades such as MAPK and PKC, and the activation of both mitochondrial-mediated apoptosis and lysosomal-mediated cell death. In addition to functional needs, during lactation the mammary gland must balance providing optimal zinc for cellular requirements with the need to secrete a substantial amount of zinc into milk to meet the requirements of the developing neonate. Finally, the mammary gland exhibits the most profound example of programmed cell death, which is driven by both apoptotic and lysosomal-mediated cell death. Two families of zinc-specific transporters regulate zinc delivery for these diverse functions. Members of the ZIP family of zinc transporters (ZIP1-14) import zinc into the cytoplasm from outside the cell or from subcellular organelles, while members of the ZnT family (ZnT1-10) export zinc from the cytoplasm. Recently, the ion channel transient receptor potential mucolipin 1 (TRPML1) has also been implicated in zinc transport. Herein, we review our current understanding of the molecular mechanisms through which mammary epithelial cells utilize zinc with a focus on the transport of zinc into discrete subcellular organelles for specific cellular functions during mammary gland development, lactation, and involution.

  1. ER and PR signaling nodes during mammary gland development

    PubMed Central

    2012-01-01

    The ovarian hormones estrogen and progesterone orchestrate postnatal mammary gland development and are implicated in breast cancer. Most of our understanding of the molecular mechanisms of estrogen receptor (ER) and progesterone receptor (PR) signaling stems from in vitro studies with hormone receptor-positive cell lines. They have shown that ER and PR regulate gene transcription either by binding to DNA response elements directly or via other transcription factors and recruiting co-regulators. In addition they cross-talk with other signaling pathways through nongenomic mechanisms. Mouse genetics combined with tissue recombination techniques have provided insights about the action of these two hormones in vivo. It has emerged that hormones act on a subset of mammary epithelial cells and relegate biological functions to paracrine factors. With regards to hormonal signaling in breast carcinomas, global gene expression analyses have led to the identification of gene expression signatures that are characteristic of ERα-positive tumors that have stipulated functional studies of hitherto poorly understood transcription factors. Here, we highlight what has been learned about ER and PR signaling nodes in these different systems and attempt to lay out in which way the insights may converge. PMID:22809143

  2. Interplay between progesterone and prolactin in mammary development and implications for breast cancer.

    PubMed

    Lee, Heather J; Ormandy, Christopher J

    2012-06-24

    Progesterone and prolactin remodel mammary morphology during pregnancy by acting on the mammary epithelial cell hierarchy. The roles of each hormone in mammary development have been well studied, but evidence of signalling cross-talk between progesterone and prolactin is still emerging. Factors such as receptor activator of NFkB ligand (RANKL) may integrate signals from both hormones to orchestrate their joint actions on the epithelial cell hierarchy. Common targets of progesterone and prolactin signalling are also likely to integrate their pro-proliferative actions in breast cancer. Therefore, a thorough understanding of the interplay between progesterone and prolactin in mammary development may reveal therapeutic targets for breast cancer. This review summarises our understanding of Pg and PRL action in mammary gland development before focusing on molecular mechanisms of signalling cross-talk and the implications for breast cancer.

  3. Mixtures of environmentally relevant endocrine disrupting chemicals affect mammary gland development in female and male rats.

    PubMed

    Mandrup, Karen Riiber; Johansson, Hanna Katarina Lilith; Boberg, Julie; Pedersen, Anne Stilling; Mortensen, Mette Sidsel; Jørgensen, Jennifer Solgaard; Vinggaard, Anne Marie; Hass, Ulla

    2015-07-01

    Estrogenic chemicals are able to alter mammary gland development in female rodents, but little is known on the effects of anti-androgens and mixtures of endocrine disrupting chemicals (EDCs) with dissimilar modes of action. Pregnant rat dams were exposed during gestation and lactation to mixtures of environmentally relevant EDCs with estrogenic, anti-androgenic or dissimilar modes of action (TotalMix) of 100-, 200- or 450-fold high end human intake estimates. Mammary glands of prepubertal and adult female and male offspring were examined. Oestrogens increased mammary outgrowth in prepubertal females and the mRNA level of matrix metalloproteinase-3, which may be a potential biomarker for increased outgrowth. Mixtures of EDCs gave rise to ductal hyperplasia in adult males. Adult female mammary glands of the TotalMix group showed morphological changes possibly reflecting increased prolactin levels. In conclusion both estrogenic and anti-androgenic chemicals given during foetal life and lactation affected mammary glands in the offspring.

  4. Impact of diethylhexyl phthalate on gene expression and development of mammary glands of pregnant mouse.

    PubMed

    Li, Lan; Liu, Jing-Cai; Zhao, Yong; Lai, Fang-Nong; Yang, Fan; Ge, Wei; Dou, Cheng-Li; Shen, Wei; Zhang, Xi-Feng; Chen, Hong

    2015-10-01

    The widely used diethylhexyl phthalate (DEHP) is a known endocrine disruptor that causes persistent alterations in the structure and function of female reproductive system, including ovaries, uterus and oviducts. To explore the molecular mechanism of the effect of DEHP on the development of mammary glands, we investigated the cell cycle, growth, proliferation and gene expression of mammary gland cells of pregnant mice exposed to DEHP. It was demonstrated, for the first time, that the mammary gland cells of pregnant mice treated with DEHP for 0.5-3.5 days post-coitum had increased proliferation, growth rate and number of cells in the G2/S phase. The expression of cell proliferation-related genes was significantly altered after short time and low-dose DEHP treatment of mammary gland cells in vivo and in vitro. These findings showed adverse effects of DEHP on mammary gland cells in pregnant mice. PMID:26170149

  5. Differential roles of ERα and ERβ in normal and neoplastic development in the mouse mammary gland.

    PubMed

    Mehta, Rajendra G; Hawthorne, Michael; Mehta, Rajeshwari R; Torres, Karen E O; Peng, Xinjian; McCormick, David L; Kopelovich, Levy

    2014-01-01

    The present experiments were performed to determine the roles of estrogen receptors α and β (ERα and ERβ) in normal and neoplastic development in the mouse mammary gland. In wild-type mice, in vivo administration of estradiol (E) + progesterone (P) stimulated mammary ductal growth and alveolar differentiation. Mammary glands from mice in which the ERβ gene has been deleted (βERKO mice) demonstrated normal ductal growth and differentiation in response to E + P. By contrast, mammary glands from mice in which the ERα gene has been deleted (αERKO mice) demonstrated only rudimentary ductal structures that did not differentiate in response to E + P. EGF demonstrates estrogen-like activity in the mammary glands of αERKO mice: treatment of αERKO mice with EGF + P (without E) supported normal mammary gland development, induced expression of progesterone receptor (PR), and increased levels of G-protein-coupled receptor (GPR30) protein. Mammary gland development in βERKO mice treated with EGF + P was comparable to that of wild-type mice receiving EGF + P; EGF had no statistically significant effects on the induction of PR or expression of GPR30 in mammary glands harvested from either wild-type mice or βERKO mice. In vitro exposure of mammary glands to 7,12-dimethylbenz[a]anthracene (DMBA) induced preneoplastic mammary alveolar lesions (MAL) in glands from wild-type mice and βERKO mice, but failed to induce MAL in mammary glands from αERKO mice. Microarray analysis of DMBA-treated mammary glands identified 28 functional pathways whose expression was significantly different in αERKO mice versus both βERKO and wild-type mice; key functions that were differentially expressed in αERKO mice included cell division, cell proliferation, and apoptosis. The data demonstrate distinct roles for ERα and ERβ in normal and neoplastic development in the mouse mammary gland, and suggest that EGF can mimic the ERα-mediated effects of E in this organ.

  6. Shh expression is required for embryonic hair follicle but not mammary gland development.

    PubMed

    Michno, Kinga; Boras-Granic, Kata; Mill, Pleasantine; Hui, C C; Hamel, Paul A

    2003-12-01

    The embryonic mammary gland and hair follicle are both derived from the ventral ectoderm, and their development depends on a number of common fundamental developmental pathways. While the Hedgehog (Hh) signaling pathway is required for hair follicle morphogenesis, the role of this pathway during embryonic mammary gland development remains undetermined. We demonstrate here that, unlike the hair follicle, both Shh and Ihh are expressed in the developing embryonic mouse mammary rudiment as early as E12.5. In Shh(-/-) embryos, hair follicle development becomes arrested at an early stage, while the mammary rudiment, which continues to express Ihh, develops in a manner indistinguishable from that of wild-type littermates. The five pairs of mammary buds in Shh(-/-) female embryos exhibit normal branching morphogenesis at E16.5, forming a rudimentary ductal structure identical to wild-type embryonic mammary glands. We further demonstrate that loss of Hh signaling causes altered cyclin D1 expression in the embryonic dermal mesenchyme. Specifically, cyclin D1 is expressed at E14.5 principally in the condensed mesenchymal cells of the presumptive hair follicles and in both mesenchymal and epithelial cells of the mammary rudiments in wild-type and Shh-deficient embryos. By E18.5, robust cyclin D1 expression is maintained in mammary rudiments of both wild-type and Shh-deficient embryos. In hair follicles of wild-type embryos by E18.5, cyclin D1 expression switches to follicular epithelial cells. In contrast, strong cyclin D1 expression is observed principally in the mesenchymal cells of arrested hair follicles in Shh(-/-) embryos at E18.5. These data reveal that, despite the common embryonic origin of hair follicles and mammary glands, distinct patterns of Hh-family expression occur in these two tissues. Furthermore, these data suggest that cyclin D1 expression in the embryonic hair follicle is mediated by both Hh-independent and Hh-dependent mechanisms.

  7. Effect of glycogen synthase kinase-3 inactivation on mouse mammary gland development and oncogenesis

    PubMed Central

    Dembowy, J; Adissu, H A; Liu, J C; Zacksenhaus, E; Woodgett, J R

    2015-01-01

    Many components of the Wnt/β-catenin signaling pathway have critical functions in mammary gland development and tumor formation, yet the contribution of glycogen synthase kinase-3 (GSK-3α and GSK-3β) to mammopoiesis and oncogenesis is unclear. Here, we report that WAP-Cre-mediated deletion of GSK-3 in the mammary epithelium results in activation of Wnt/β-catenin signaling and induces mammary intraepithelial neoplasia that progresses to squamous transdifferentiation and development of adenosquamous carcinomas at 6 months. To uncover possible β-catenin-independent activities of GSK-3, we generated mammary-specific knockouts of GSK-3 and β-catenin. Squamous transdifferentiation of the mammary epithelium was largely attenuated, however, mammary epithelial cells lost the ability to form mammospheres suggesting perturbation of stem cell properties unrelated to loss of β-catenin alone. At 10 months, adenocarcinomas that developed in glands lacking GSK-3 and β-catenin displayed elevated levels of γ-catenin/plakoglobin as well as activation of the Hedgehog and Notch pathways. Collectively, these results establish the two isoforms of GSK-3 as essential integrators of multiple developmental signals that act to maintain normal mammary gland function and suppress tumorigenesis. PMID:25195860

  8. [Progress on the miRNA related with mammary gland development and lactation].

    PubMed

    Jin, Xiao-Lu; Yang, Jian-Xiang; Li, Zhen; Liu, Hong-Yun; Liu, Jian-Xin

    2013-06-01

    MicroRNAs (miRNAs) are non-coding RNAs that play important roles in post transcriptional regulation. They are involved in the regulation of mammary gland development and lactation. In this paper, we summarized the expression pattern of miRNAs which varied with tissues and lactation stages, and the functions of several miRNAs are also briefly reviewed. The objective of this work is to give reference for further study on miRNAs in mammary gland, and to provide theoretical basis and ideas for the use of miRNAs in improving healthy development of mammary gland and regulating the efficiency of lactation and the quality of milk.

  9. IGF-IR Mediated Mammary Tumorigenesis Is Enhanced during Pubertal Development

    PubMed Central

    Campbell, Craig I.; Moorehead, Roger A.

    2014-01-01

    Although breast cancer typically develops in women over the age of 40, it remains unclear when breast cancer initiating events occur or whether the mammary gland is particularly susceptible to oncogenic transformation at a particular developmental stage. Using MTB-IGFIR transgenic mice that overexpress type I insulin-like growth factor receptor (IGF-IR) in a doxycycline-inducible manner, mammary tumorigenesis was initiated at different developmental stages. Tumor multiplicity was significantly increased while tumor latency was significantly decreased when the IGF-IR transgene was expressed during pubertal development compared to post-pubertal transgene expression. Moreover, metastatic spread of mammary tumors to the lungs was approximately twice as likely when IGF-IR was overexpressed in pubertal mice compared to post-pubertal mice. In addition, engraftment of pubertal MTB-IGFIR mammary tissue into cleared mammary fat pads of pubertal hosts produced tumors more frequently and faster than engraftment into adult hosts. These experiments show that the mammary microenvironment created during puberty renders mammary epithelial cells particularly susceptible to transformation. PMID:25259518

  10. ENVIRONMENTAL TOXICANTS AND DISRUPTED MAMMARY GLAND DEVELOPMENT: THE WINDOW OF SUSCEPTIBILITY

    EPA Science Inventory

    Environmental Toxicants and Altered Mammary Gland Development: The window of susceptibility. Suzanne E. Fenton, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711

    There are several enviro...

  11. ENVIRONMENTAL TOXICANTS AND ALTERED MAMMARY GLAND DEVELOPMENT: THE WINDOW OF SUSCEPTIBILITY

    EPA Science Inventory

    Environmental Toxicants and Altered Mammary Gland Development: The window of susceptibility. Suzanne E. Fenton, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711

    There are several environm...

  12. Loss of vitamin D receptor signaling from the mammary epithelium or adipose tissue alters pubertal glandular development.

    PubMed

    Johnson, Abby L; Zinser, Glendon M; Waltz, Susan E

    2014-10-15

    Vitamin D₃ receptor (VDR) signaling within the mammary gland regulates various postnatal stages of glandular development, including puberty, pregnancy, involution, and tumorigenesis. Previous studies have shown that vitamin D₃ treatment induces cell-autonomous growth inhibition and differentiation of mammary epithelial cells in culture. Furthermore, mammary adipose tissue serves as a depot for vitamin D₃ storage, and both epithelial cells and adipocytes are capable of bioactivating vitamin D₃. Despite the pervasiveness of VDR in mammary tissue, individual contributions of epithelial cells and adipocytes, as well as the VDR-regulated cross-talk between these two cell types during pubertal mammary development, have yet to be investigated. To assess the cell-type specific effect of VDR signaling during pubertal mammary development, novel mouse models with mammary epithelial- or adipocyte-specific loss of VDR were generated. Interestingly, loss of VDR in either cellular compartment accelerated ductal morphogenesis with increased epithelial cell proliferation and decreased apoptosis within terminal end buds. Conversely, VDR signaling specifically in the mammary epithelium modulated hormone-induced alveolar growth, as ablation of VDR in this cell type resulted in precocious alveolar development. In examining cellular cross-talk ex vivo, we show that ligand-dependent VDR signaling in adipocytes significantly inhibits mammary epithelial cell growth in part through the vitamin D₃-dependent production of the cytokine IL-6. Collectively, these studies delineate independent roles for vitamin D₃-dependent VDR signaling in mammary adipocytes and epithelial cells in controlling pubertal mammary gland development.

  13. Pleiotropic functions of fibroblast growth factor signaling in embryonic mammary gland development.

    PubMed

    Kim, Eun-Jung; Jung, Han-Sung; Lu, Pengfei

    2013-06-01

    The mammary gland is an ectodermal appendage and a defining feature of mammals. Consistent with it being a recent evolutionary novelty, many of the molecules essential for the ontogeny and morphogenesis of various vertebrate organs, including those in the fibroblast growth factor (FGF) signaling pathway, are co-opted for induction, maintenance and morphogenesis of the mammary glands. Understanding the mechanism whereby FGF signaling regulates the fundamental cell behavior during normal mammary gland develop may facilitate determination of the consequences of its deregulation during breast cancer progression.

  14. Expression of the whey acidic protein in transgenic pigs impairs mammary development.

    PubMed

    Shamay, A; Pursel, V G; Wilkinson, E; Wall, R J; Hennighausen, L

    1992-05-01

    The whey acidic protein has been found in milk of mice, rats, rabbits and camels, and its gene is expressed specifically in mammary tissue at late pregnancy and throughout lactation. A characteristic of whey acidic protein is the 'four-disulfide-core' signature which is also present in proteins involved in organ development. We have generated six lines of transgenic pigs which carry a mouse whey acidic protein transgene and express it at high levels in their mammary glands. Transgenic sows from three lines could not produce sufficient quantities of milk to support normal development of healthy offspring. This phenotype appears to be similar, if not identical, to the milchlos phenotype exhibited by mice expressing whey acidic protein transgenes. Mammary tissue from post-partum milchlos sows had an immature histological appearance, which was distinct from that observed during normal development or involution. Expression of the whey acidic protein transgene was found in mammary tissue from sexually immature pigs from milchlos lines, but not in sows from lines that appeared to lactate normally. We suggest that precocious synthesis of whey acidic protein impairs mammary development and function. Impaired mammary development due to inappropriate timing of whey acidic protein expression is consistent with the notion that proteins with the 'four-disulfide-core' signature participate in tissue formation. PMID:1284481

  15. Lifelong exposure to n-3 PUFA affects pubertal mammary gland development.

    PubMed

    Anderson, Breanne M; MacLennan, Mira B; Hillyer, Lyn M; Ma, David W L

    2014-06-01

    There is growing evidence that early developmental periods may importantly influence future breast cancer risk. Also, there is great interest in the role of dietary fat in breast cancer risk, but the role of dietary fat during pubertal mammary gland development remains poorly understood. This study investigated the effect of n-3 polyunsaturated fatty acids (PUFA) using complementary dietary and genetic approaches to examine the effect of lifelong exposure of n-3 PUFA or n-6 PUFA (control) on mammary gland development and fatty acid composition. n-3 PUFA from both diet and genetics were enriched in mammary glands as early as 3 weeks of age. Parameters related to mammary gland development, including number of terminal end buds (TEB), percent coverage of ductal tree, and infiltration of TEB, were influenced by n-3 PUFA at 3 and 4 weeks of age. Overall, findings suggest that n-3 PUFA incorporation into the mammary gland early in life plays a role in the morphological development of the mammary gland during puberty.

  16. Endocrine hormones and local signals during the development of the mouse mammary gland.

    PubMed

    Brisken, Cathrin; Ataca, Dalya

    2015-01-01

    Most of mammary gland development occurs postnatally under the control of female reproductive hormones, which in turn interact with other endocrine factors. While hormones impinge on many tissues and trigger very complex biological responses, tissue recombination experiments with hormone receptor-deficient mammary epithelia revealed eminent roles for estrogens, progesterone, and prolactin receptor (PrlR) signaling that are intrinsic to the mammary epithelium. A subset of the luminal mammary epithelial cells expresses the estrogen receptor α (ERα), the progesterone receptor (PR), and the PrlR and act as sensor cells. These cells convert the detected systemic signals into local signals that are developmental stage-dependent and may be direct, juxtacrine, or paracrine. This setup ensures that the original input is amplified and that the biological responses of multiple cell types can be coordinated. Some key mediators of hormone action have been identified such as Wnt, EGFR, IGFR, and RANK signaling. Multiple signaling pathways such as FGF, Hedgehog, and Notch signaling participate in driving different aspects of mammary gland development locally but how they link to the hormonal control remains to be elucidated. An increasing number of endocrine factors are appearing to have a role in mammary gland development, the adipose tissue is increasingly recognized to play a role in endocrine regulation, and a complex role of the immune system with multiple different cell types is being revealed. For further resources related to this article, please visit the WIREs website.

  17. Development and Characterization of a Novel Rat Model of Estrogen-Induced Mammary Cancer

    PubMed Central

    Dennison, Kirsten L.; Samanas, Nyssa Becker; Harenda, Quincy Eckert; Hickman, Maureen Peters; Seiler, Nicole L.; Ding, Lina; Shull, James D.

    2015-01-01

    The ACI rat model of 17β-estradiol (E2)-induced mammary cancer is highly relevant for use in establishing the endocrine, genetic and environmental bases of breast cancer etiology and identifying novel agents and strategies for preventing breast cancer. E2 treatment rapidly induces mammary cancer in female ACI rats and simultaneously induces pituitary lactotroph hyperplasia and adenoma. The pituitary tumors can result in undesired morbidity which compromises long term studies focused on mammary cancer etiology and prevention. We have defined the genetic bases of susceptibility to E2-induced mammary cancers and pituitary tumors and have utilized the knowledge gained in these studies to develop a novel inbred rat strain, designated ACWi, that retains the high degree of susceptibility to E2-induced mammary cancer exhibited by ACI rats but lacks the treatment related morbidity associated with pituitary lactotroph hyperplasia/adenoma. When treated with E2, female ACWi rats developed palpable mammary cancer at a median latency of 116 days, an incidence of 100% by 161 days and exhibited an average of 15.6 mammary tumors per rat following 196 days of treatment. These parameters did not differ from that observed for contemporaneously treated ACI rats. None of the E2 treated ACWi rats were euthanized prior to the intended experimental end point due to any treatment related morbidity other than mammary cancer burden, whereas 20% of contemporaneously treated ACI rats exhibited treatment related morbidity that necessitated premature euthanasia. The ACWi rat strain is well suited for use by those in the research community focusing on breast cancer etiology and prevention. PMID:25800038

  18. Growth and development of the mammary glands of livestock: a veritable barnyard of opportunities.

    PubMed

    Rowson, Ashley R; Daniels, Kristy M; Ellis, Steven E; Hovey, Russell C

    2012-07-01

    The mammary glands of all mammals are rich and diverse in their histomorphogenesis, developmental biology, genomics and metabolism. Domesticated livestock comprise a unique population for the analysis of mammary gland and lactation biology, where much of what has been learned about these topics originates from studies of these species. However, with the strong trend toward using rodents as flexible and attractive models for normal mammary biology and cancer, there is a growing void of new information related to biology of the mammary glands in these relevant and informative domestic livestock. In turn, this trend threatens to reduce opportunities to either capitalize on an abundance of pre-existing data or to apply this information to studies of lactation and cancer. Herein we review the unique and discerning features of mammary gland development in several domestic livestock species including cows, sheep and pigs and provide an overview of the factors regulating it. At the same time we discuss some of the key considerations for studying these species, their limitations, and the associated opportunities. From such an analysis it quickly becomes clear that much remains to be learned about the mammary glands of domestic livestock, particularly given their many similarities to the human breast, the unique biological mechanisms they employ, and the phenotypic variation they afford.

  19. Key signalling nodes in mammary gland development and cancer. Mitogen-activated protein kinase signalling in experimental models of breast cancer progression and in mammary gland development.

    PubMed

    Whyte, Jacqueline; Bergin, Orla; Bianchi, Alessandro; McNally, Sara; Martin, Finian

    2009-01-01

    Seven classes of mitogen-activated protein kinase (MAPK) intracellular signalling cascades exist, four of which are implicated in breast disease and function in mammary epithelial cells. These are the extracellular regulated kinase (ERK)1/2 pathway, the ERK5 pathway, the p38 pathway and the c-Jun N-terminal kinase (JNK) pathway. In some forms of human breast cancer and in many experimental models of breast cancer progression, signalling through the ERK1/2 pathway, in particular, has been implicated as being important. We review the influence of ERK1/2 activity on the organised three-dimensional association of mammary epithelial cells, and in models of breast cancer cell invasion. We assess the importance of epidermal growth factor receptor family signalling through ERK1/2 in models of breast cancer progression and the influence of ERK1/2 on its substrate, the oestrogen receptor, in this context. In parallel, we consider the importance of these MAPK-centred signalling cascades during the cycle of mammary gland development. Although less extensively studied, we highlight the instances of signalling through the p38, JNK and ERK5 pathways involved in breast cancer progression and mammary gland development.

  20. Loss of Panx1 Impairs Mammary Gland Development at Lactation: Implications for Breast Tumorigenesis

    PubMed Central

    Stewart, Michael K. G.; Plante, Isabelle; Penuela, Silvia; Laird, Dale W.

    2016-01-01

    Pannexin1 (Panx1) subunits oligomerize to form large-pore channels between the intracellular and extracellular milieu that have been shown to regulate proliferation, differentiation and cell death mechanisms. These key cellular responses are ultimately necessary for normal tissue development and function but the role of Panx1 in development, differentiation and function in many tissues remains unexplored, including that of the breast. Panx1 was identified to be expressed in the mammary gland through western blot and immunofluorescent analysis and is dynamically upregulated during pregnancy and lactation. In order to evaluate the role of Panx1 in the context of mammary gland development and function, Panx1-/- mice were evaluated in comparison to wild-type mice in the mammary glands of virgin, lactating and involuting mice. Our results revealed that Panx1 ablation did not affect virgin or involuting mammary glands following histological and whole mount analysis. Panx1 was necessary for timely alveolar development during early lactation based on a decreased number of alveolar lumen following histological analysis and reduced proliferation following Ki67 immunofluorescent labelling. Importantly, the loss of Panx1 in lactating mammary glands did not overtly affect epithelial or secretory differentiation of the mammary gland suggesting that Panx1 is not critical in normal mammary gland function. In addition, PANX1 mRNA expression was correlated with negative clinical outcomes in patients with breast cancer using in silico arrays. Together, our results suggest that Panx1 is necessary for timely alveolar development following the transition from pregnancy to lactation, which may have implications extending to patients with breast cancer. PMID:27099931

  1. Loss of Panx1 Impairs Mammary Gland Development at Lactation: Implications for Breast Tumorigenesis.

    PubMed

    Stewart, Michael K G; Plante, Isabelle; Penuela, Silvia; Laird, Dale W

    2016-01-01

    Pannexin1 (Panx1) subunits oligomerize to form large-pore channels between the intracellular and extracellular milieu that have been shown to regulate proliferation, differentiation and cell death mechanisms. These key cellular responses are ultimately necessary for normal tissue development and function but the role of Panx1 in development, differentiation and function in many tissues remains unexplored, including that of the breast. Panx1 was identified to be expressed in the mammary gland through western blot and immunofluorescent analysis and is dynamically upregulated during pregnancy and lactation. In order to evaluate the role of Panx1 in the context of mammary gland development and function, Panx1-/- mice were evaluated in comparison to wild-type mice in the mammary glands of virgin, lactating and involuting mice. Our results revealed that Panx1 ablation did not affect virgin or involuting mammary glands following histological and whole mount analysis. Panx1 was necessary for timely alveolar development during early lactation based on a decreased number of alveolar lumen following histological analysis and reduced proliferation following Ki67 immunofluorescent labelling. Importantly, the loss of Panx1 in lactating mammary glands did not overtly affect epithelial or secretory differentiation of the mammary gland suggesting that Panx1 is not critical in normal mammary gland function. In addition, PANX1 mRNA expression was correlated with negative clinical outcomes in patients with breast cancer using in silico arrays. Together, our results suggest that Panx1 is necessary for timely alveolar development following the transition from pregnancy to lactation, which may have implications extending to patients with breast cancer. PMID:27099931

  2. Low-dose effects of bisphenol A on mammary gland development in rats.

    PubMed

    Mandrup, K; Boberg, J; Isling, L K; Christiansen, S; Hass, U

    2016-07-01

    Bisphenol A (BPA) is widely used in food contact materials, toys, and other products. Several studies have indicated that effects observed at doses near human exposure levels may not be observed at higher doses. Many studies have shown effects on mammary glands at low doses of BPA, however, because of small number of animals or few doses investigated these data have not been used by EFSA as point of departure for the newly assessed tolerable daily intake (TDI). We performed a study with perinatal exposure to BPA (0, 0.025, 0.25, 5, and 50 mg/kg bw/day) in rats (n = 22 mated/group). One of the aims was to perform a study robust enough to contribute to the risk assessment of BPA and to elucidate possible biphasic dose-response relationships. We investigated mammary gland effects in the offspring at 22, 100, and 400 days of age. Male offspring showed increased mammary outgrowth on pup day (PD) 22 at 0.025 mg/kg BPA, indicating an increased mammary development at this low dose only. Increased prevalence of intraductal hyperplasia was observed in BPA females exposed to 0.25 mg/kg at PD 400, but not at PD 100, and not at higher or lower doses. The present findings support data from the published literature showing that perinatal exposure to BPA can induce increased mammary growth and proliferative lesions in rodents. Our results indicate that low-dose exposure to BPA can affect mammary gland development in male and female rats, although higher doses show a different pattern of effects. The observed intraductal hyperplasia in female rats could be associated with an increased risk for developing hyperplastic lesions, which are parallels to early signs of breast neoplasia in women. Collectively, current knowledge on effects of BPA on mammary gland at low doses indicates that highly exposed humans may not be sufficiently protected. PMID:27088260

  3. Low-dose effects of bisphenol A on mammary gland development in rats.

    PubMed

    Mandrup, K; Boberg, J; Isling, L K; Christiansen, S; Hass, U

    2016-07-01

    Bisphenol A (BPA) is widely used in food contact materials, toys, and other products. Several studies have indicated that effects observed at doses near human exposure levels may not be observed at higher doses. Many studies have shown effects on mammary glands at low doses of BPA, however, because of small number of animals or few doses investigated these data have not been used by EFSA as point of departure for the newly assessed tolerable daily intake (TDI). We performed a study with perinatal exposure to BPA (0, 0.025, 0.25, 5, and 50 mg/kg bw/day) in rats (n = 22 mated/group). One of the aims was to perform a study robust enough to contribute to the risk assessment of BPA and to elucidate possible biphasic dose-response relationships. We investigated mammary gland effects in the offspring at 22, 100, and 400 days of age. Male offspring showed increased mammary outgrowth on pup day (PD) 22 at 0.025 mg/kg BPA, indicating an increased mammary development at this low dose only. Increased prevalence of intraductal hyperplasia was observed in BPA females exposed to 0.25 mg/kg at PD 400, but not at PD 100, and not at higher or lower doses. The present findings support data from the published literature showing that perinatal exposure to BPA can induce increased mammary growth and proliferative lesions in rodents. Our results indicate that low-dose exposure to BPA can affect mammary gland development in male and female rats, although higher doses show a different pattern of effects. The observed intraductal hyperplasia in female rats could be associated with an increased risk for developing hyperplastic lesions, which are parallels to early signs of breast neoplasia in women. Collectively, current knowledge on effects of BPA on mammary gland at low doses indicates that highly exposed humans may not be sufficiently protected.

  4. Localization and quantitation of macrophages, mast cells, and eosinophils in the developing bovine mammary gland.

    PubMed

    Beaudry, K L; Parsons, C L M; Ellis, S E; Akers, R M

    2016-01-01

    Prepubertal mammary development involves elongation and branching of ducts and stromal tissue remodeling. This process is highly regulated and in mice is known to be affected by the presence of innate immune cells. Whether or not such immune cells are present or involved in bovine mammary development is unknown. For the first time, we determined the presence, location (relative to mammary ductal structures), and changes in numbers of eosinophils, mast cells, and macrophages in prepubertal bovine mammary tissue, and evaluated the effects of age, ovariectomy, and exogenous estrogen on numbers of each cell type. Chemical stains and immunofluorescence were used to identify the 3 cell types in formalin-fixed, paraffin-embedded mammary tissue from prepubertal female calves from 3 archived tissue sets. The ontogeny tissue set included samples of mammary tissue from female calves (n=4/wk) from birth to 6 wk of age. The ovary tissue set contained samples from ovary intact and ovariectomized heifers allowing us to investigate the influence of the ovaries on immune cells in the developing mammary gland in prepubertal heifers. Nineteen animals were intact or ovariectomized 30 d before sampling; they were 90, 120, or 150 d old at the time of sampling. A third tissue set, the estrogen set, allowed us to determine the effect of exogenous estrogen on innate immune cells in the gland. Eosinophils were identified via Luna staining, mast cells by May-Grunwald Giemsa staining, and macrophages with immunofluorescence. Key findings were that more eosinophils and mast cells were observed in near versus far stroma in the ontogeny and ovary tissue sets but not estrogen. More macrophages were observed in near versus far stroma in ontogeny animals. Eosinophils were more abundant in the younger animals, and fewer macrophages tended to be observed in ovariectomized heifers as compared with intact heifers and estrogen treatment resulted in a reduction in cell numbers. In summary, we show for

  5. CD151 represses mammary gland development by maintaining the niches of progenitor cells

    PubMed Central

    Yin, Yuanqin; Deng, Xinyu; Liu, Zeyi; Baldwin, Lauren A; Lefringhouse, Jason; Zhang, Jiayang; Hoff, John T; Erfani, Sonia F; Rucker, Edmund B; O'Connor, Kathleen; Liu, Chunming; Wu, Yadi; Zhou, Binhua P; Yang, Xiuwei H

    2014-01-01

    Tetraspanin CD151 interacts with laminin-binding integrins (i.e., α3β1, α6β1 and α6β4) and other cell surface molecules to control diverse cellular and physiological processes, ranging from cell adhesion, migration and survival to tissue architecture and homeostasis. Here, we report a novel role of CD151 in maintaining the branching morphogenesis and activity of progenitor cells during the pubertal development of mammary glands. In contrast to the disruption of laminin-binding integrins, CD151 removal in mice enhanced the tertiary branching in mammary glands by 2.4-fold and the number of terminal end buds (TEBs) by 30%, while having minimal influence on either primary or secondary ductal branching. Consistent with these morphological changes are the skewed distribution of basal/myoepithelial cells and a 3.2-fold increase in proliferating Ki67-positive cells. These novel observations suggest that CD151 impacts the branching morphogenesis of mammary glands by upregulating the activities of bipotent progenitor cells. Indeed, our subsequent analyses indicate that upon CD151 removal the proportion of CD24HiCD49fLow progenitor cells in the mammary gland increased by 34%, and their proliferating and differentiating activities were significantly upregulated. Importantly, fibronectin, a pro-branching extracellular matrix (ECM) protein deposited underlying mammary epithelial or progenitor cells, increased by >7.2-fold. Moreover, there was a concomitant increase in the expression and nuclear distribution of Slug, a transcription factor implicated in the maintenance of mammary progenitor cell activities. Taken together, our studies demonstrate that integrin-associated CD151 represses mammary branching morphogenesis by controlling progenitor cell activities, ECM integrity and transcription program. PMID:25486358

  6. Integrated extracellular matrix signaling in mammary gland development and breast cancer progression.

    PubMed

    Zhu, Jieqing; Xiong, Gaofeng; Trinkle, Christine; Xu, Ren

    2014-09-01

    Extracellular matrix (ECM), a major component of the cellular microenvironment, plays critical roles in normal tissue morphogenesis and disease progression. Binding of ECM to membrane receptor proteins, such as integrin, discoidin domain receptors, and dystroglycan, elicits biochemical and biomechanical signals that control cellular architecture and gene expression. These ECM signals cooperate with growth factors and hormones to regulate cell migration, differentiation, and transformation. ECM signaling is tightly regulated during normal mammary gland development. Deposition and alignment of fibrillar collagens direct migration and invasion of mammary epithelial cells during branching morphogenesis. Basement membrane proteins are required for polarized acinar morphogenesis and milk protein expression. Deregulation of ECM proteins in the long run is sufficient to promote breast cancer development and progression. Recent studies demonstrate that the integrated biophysical and biochemical signals from ECM and soluble factors are crucial for normal mammary gland development as well as breast cancer progression.

  7. Epigenetic Modifications Unlock the Milk Protein Gene Loci during Mouse Mammary Gland Development and Differentiation

    PubMed Central

    Rijnkels, Monique; Freeman-Zadrowski, Courtneay; Hernandez, Joseph; Potluri, Vani; Wang, Liguo; Li, Wei; Lemay, Danielle G.

    2013-01-01

    Background Unlike other tissues, development and differentiation of the mammary gland occur mostly after birth. The roles of systemic hormones and local growth factors important for this development and functional differentiation are well-studied. In other tissues, it has been shown that chromatin organization plays a key role in transcriptional regulation and underlies epigenetic regulation during development and differentiation. However, the role of chromatin organization in mammary gland development and differentiation is less well-defined. Here, we have studied the changes in chromatin organization at the milk protein gene loci (casein, whey acidic protein, and others) in the mouse mammary gland before and after functional differentiation. Methodology/Principal Findings Distal regulatory elements within the casein gene cluster and whey acidic protein gene region have an open chromatin organization after pubertal development, while proximal promoters only gain open-chromatin marks during pregnancy in conjunction with the major induction of their expression. In contrast, other milk protein genes, such as alpha-lactalbumin, already have an open chromatin organization in the mature virgin gland. Changes in chromatin organization in the casein gene cluster region that are present after puberty persisted after lactation has ceased, while the changes which occurred during pregnancy at the gene promoters were not maintained. In general, mammary gland expressed genes and their regulatory elements exhibit developmental stage- and tissue-specific chromatin organization. Conclusions/Significance A progressive gain of epigenetic marks indicative of open/active chromatin on genes marking functional differentiation accompanies the development of the mammary gland. These results support a model in which a chromatin organization is established during pubertal development that is then poised to respond to the systemic hormonal signals of pregnancy and lactation to achieve the

  8. Ectodysplasin/NF-κB signaling in embryonic mammary gland development.

    PubMed

    Lindfors, Päivi H; Voutilainen, Maria; Mikkola, Marja L

    2013-06-01

    The ectodysplasin (Eda) signaling pathway consists of a TNF-like ligand Eda, its receptor Edar, and an adaptor protein Edaradd and its activation leads to NF-κB mediated transcription. In humans, mutations in the EDA pathway genes cause hypohidrotic ectodermal dysplasia, a disorder characterized by defective formation of hair follicles, teeth, and several exocrine glands including the breast. Embryonic mammary gland development proceeds via placode, bud, bulb and sprout stages before the onset of branching morphogenesis. Studies on mouse models have linked Eda with two aspects of embryonic mammary gland morphogenesis: placode induction and ductal growth and branching. Here we summarize the current knowledge on the role of Eda/NF-κB in mammary gland development.

  9. Epigenetic modifications unlock the milk protein gene loci during mouse mammary gland development and differentiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unlike with other tissues, development and differentiation of the mammary gland occur mostly after birth. The roles of systemic hormones and local growth factors important for this development and functional differentiation are well-studied. In other tissues, it has been shown that chromatin organiz...

  10. Growth hormone and insulin-like growth factor-I in the transition from normal mammary development to preneoplastic mammary lesions.

    PubMed

    Kleinberg, David L; Wood, Teresa L; Furth, Priscilla A; Lee, Adrian V

    2009-02-01

    Adult female mammary development starts at puberty and is controlled by tightly regulated cross-talk between a group of hormones and growth factors. Although estrogen is the initial driving force and is joined by luteal phase progesterone, both of these hormones require GH-induced IGF-I in the mammary gland in order to act. The same group of hormones, when experimentally perturbed, can lead to development of hyperplastic lesions and increase the chances, or be precursors, of mammary carcinoma. For example, systemic administration of GH or IGF-I causes mammary hyperplasia, and overproduction of IGF-I in transgenic animals can cause the development of usual or atypical hyperplasias and sometimes carcinoma. Although studies have clearly demonstrated the transforming potential of both GH and IGF-I receptor in cell culture and in animals, debate remains as to whether their main role is actually instructive or permissive in progression to cancer in vivo. Genetic imprinting has been shown to occur in precursor lesions as early as atypical hyperplasia in women. Thus, the concept of progression from normal development to cancer through precursor lesions sensitive to hormones and growth factors discussed above is gaining support in humans as well as in animal models. Indeed, elevation of estrogen receptor, GH, IGF-I, and IGF-I receptor during progression suggests a role for these pathways in this process. New agents targeting the GH/IGF-I axis may provide a novel means to block formation and progression of precursor lesions to overt carcinoma. A novel somatostatin analog has recently been shown to prevent mammary development in rats via targeted IGF-I action inhibition at the mammary gland. Similarly, pegvisomant, a GH antagonist, and other IGF-I antagonists such as IGF binding proteins 1 and 5 also block mammary gland development. It is, therefore, possible that inhibition of IGF-I action, or perhaps GH, in the mammary gland may eventually play a role in breast cancer

  11. Hypoxia-inducible factor-1α induces ErbB4 signaling in the differentiating mammary gland.

    PubMed

    Paatero, Ilkka; Seagroves, Tiffany N; Vaparanta, Katri; Han, Wen; Jones, Frank E; Johnson, Randall S; Elenius, Klaus

    2014-08-01

    Conditional knock-out of Hif1a in the mouse mammary gland impairs lobuloalveolar differentiation during lactation. Here, we demonstrate that expression of ErbB4 was reduced in the lobulalveoli of mice with mammary gland-specific deletion of Hif1a. Erbb4 was not, however, a direct target gene for transcriptional regulation by HIF-1α in vitro. HIF-1α overexpression or HIF accumulating prolyl hydroxylase inhibitors reduced ErbB4 endocytosis, promoted transcriptional co-regulatory activity of ErbB4, and stimulated ErbB4-induced differentiation of mammary carcinoma cells. Consistently, RNA interference-mediated down-regulation of HIF-1α resulted in reduced ErbB4 protein amount and reduced mammary carcinoma cell differentiation. These findings indicate that HIF-1α is a physiologically relevant regulator of ErbB4 and that ErbB4 is involved in HIF-regulated differentiation of the mammary gland.

  12. Amino acids and mammary gland development: nutritional implications for milk production and neonatal growth.

    PubMed

    Rezaei, Reza; Wu, Zhenlong; Hou, Yongqing; Bazer, Fuller W; Wu, Guoyao

    2016-01-01

    Milk is synthesized by mammary epithelial cells of lactating mammals. The synthetic capacity of the mammary gland depends largely on the number and efficiency of functional mammary epithelial cells. Structural development of the mammary gland occurs during fetal growth, prepubertal and post-pubertal periods, pregnancy, and lactation under the control of various hormones (particularly estrogen, growth hormone, insulin-like growth factor-I, progesterone, placental lactogen, and prolactin) in a species- and stage-dependent manner. Milk is essential for the growth, development, and health of neonates. Amino acids (AA), present in both free and peptide-bound forms, are the most abundant organic nutrients in the milk of farm animals. Uptake of AA from the arterial blood of the lactating dam is the ultimate source of proteins (primarily β-casein and α-lactalbumin) and bioactive nitrogenous metabolites in milk. Results of recent studies indicate extensive catabolism of branched-chain AA (leucine, isoleucine and valine) and arginine to synthesize glutamate, glutamine, alanine, aspartate, asparagine, proline, and polyamines. The formation of polypeptides from AA is regulated not only by hormones (e.g., prolactin, insulin and glucocorticoids) and the rate of blood flow across the lactating mammary gland, but also by concentrations of AA, lipids, glucose, vitamins and minerals in the maternal plasma, as well as the activation of the mechanistic (mammalian) target rapamycin signaling by certain AA (e.g., arginine, branched-chain AA, and glutamine). Knowledge of AA utilization (including metabolism) by mammary epithelial cells will enhance our fundamental understanding of lactation biology and has important implications for improving the efficiency of livestock production worldwide. PMID:27042295

  13. MiR-21 is under control of STAT5 but is dispensable for mammary development and lactation.

    PubMed

    Feuermann, Yonatan; Kang, Keunsoo; Shamay, Avi; Robinson, Gertraud W; Hennighausen, Lothar

    2014-01-01

    Development of mammary alveolar epithelium during pregnancy is controlled by prolactin, through the transcription factors STAT5A/B that activate specific sets of target genes. Here we asked whether some of STAT5's functions are mediated by microRNAs. The miR-21 promoter sequence contains a bona-fide STAT5 binding site and miR-21 levels increased in HC11 mammary cells upon prolactin treatment. In vivo miR-21 was abundantly expressed in mammary epithelium at day 6 of pregnancy. Analysis of mice lacking miR-21 revealed that their mammary tissue developed normally during pregnancy and dams were able to nurse their pups. Our study demonstrated that although expression of miR-21 is under prolactin control through the transcription factors STAT5A/B its presence is dispensable for mammary development and lactation. PMID:24497923

  14. MiR-21 Is under Control of STAT5 but Is Dispensable for Mammary Development and Lactation

    PubMed Central

    Feuermann, Yonatan; Kang, Keunsoo; Shamay, Avi; Robinson, Gertraud W.; Hennighausen, Lothar

    2014-01-01

    Development of mammary alveolar epithelium during pregnancy is controlled by prolactin, through the transcription factors STAT5A/B that activate specific sets of target genes. Here we asked whether some of STAT5's functions are mediated by microRNAs. The miR-21 promoter sequence contains a bona-fide STAT5 binding site and miR-21 levels increased in HC11 mammary cells upon prolactin treatment. In vivo miR-21 was abundantly expressed in mammary epithelium at day 6 of pregnancy. Analysis of mice lacking miR-21 revealed that their mammary tissue developed normally during pregnancy and dams were able to nurse their pups. Our study demonstrated that although expression of miR-21 is under prolactin control through the transcription factors STAT5A/B its presence is dispensable for mammary development and lactation. PMID:24497923

  15. ADVERSE EFFECTS OF TCDD ON MAMMARY GLAND DEVELOPMENT IN LONG EVANS RATS: A TWO GENERATIONAL STUDY

    EPA Science Inventory

    Recent studies have demonstrated variable effects on mammary gland development in rat offspring exposed to TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin, 1 ug/kg, gavage) on day 15 of gestation. We have characterized these effects in Long Evans rats, in both one and two-generational...

  16. The ADAM17-amphiregulin-EGFR axis in mammary development and cancer.

    PubMed

    Sternlicht, Mark D; Sunnarborg, Susan W

    2008-06-01

    In order to fulfill its function of producing and delivering sufficient milk to newborn mammalian offspring, the mammary gland first has to form an extensive ductal network. As in all phases of mammary development, hormonal cues elicit local intra- and inter-cellular signaling cascades that regulate ductal growth and differentiation. Among other things, ductal development requires the epidermal growth factor receptor (EGFR), its ligand amphiregulin (AREG), and the transmembrane metalloproteinase ADAM17, which can cleave and release AREG from the cell surface so that it may interact with its receptor. Tissue recombination and transplantation studies demonstrate that EGFR phosphorylation and ductal development proceed only when ADAM17 and AREG are expressed on mammary epithelial cells and EGFR is present on stromal cells, and that local administration of soluble AREG can rescue the development of ADAM17-deficient transplants. Thus proper mammary morphogenesis requires the ADAM17-mediated release of AREG from ductal epithelial cells, the subsequent activation of EGFR on stromal cells, and EGFR-dependent stromal responses that in return elicit a new set of epithelial responses, all culminating in the formation of a fully functional ductal tree. This, however, raises new issues concerning what may act upstream, downstream or in parallel with the ADAM17-AREG-EGFR axis, how it may become hijacked or corrupted during the onset and evolution of cancer, and how such ill effects may be confronted.

  17. NONYLPHENOL AND ATRAZINE INDUCE INVERSE EFFECTS ON MAMMARY GLAND DEVELOPMENT IN FEMALE RATS EXPOSED IN UTERO

    EPA Science Inventory

    Nonylphenol and Atrazine Induce Inverse Effects on Mammary Gland Development in Female Rats Exposed In Utero.
    HJ Moon1, SY Han1, CC Davis2, and SE Fenton2
    1 Department of Toxicology, NITR, Korea FDA, 5Nokbun-Dong, Eunpyung-Gu, Seoul, Korea and 2 Reproductive Toxicology Divi...

  18. INFLUENCE OF ENDOCRINE DISRUPTING COMPOUNDS (EDCS) ON MAMMARY GLAND DEVELOPMENT AND TUMOR SUSCEPTIBILITY

    EPA Science Inventory

    Influence of Endocrine Disrupting Compounds (EDCs) on Mammary Gland Development and Tumor Susceptibility.

    Suzanne E. Fenton1, and Jennifer Rayner1,2

    1 Reproductive Toxicology Division, NHEERL/ORD, U.S. EPA, Research Triangle Park, NC, and 2 Department of Environmen...

  19. GESTATIONAL EXPOSURE TO NONYLPHENOL CAUSES PRECOCIOUS MAMMARY GLAND DEVELOPMENT IN FEMALE RAT OFFSPRING

    EPA Science Inventory

    This study examined whether or not exposure to 4-nonylphenol (NP) during late gestation affects reproductive and mammary development in the offspring of female rats. Time pregnant Long Evans rats were gavaged with NP (10 or 100 mg/kg), atrazine (ATR, 100 mg/kg), or corn oil on ge...

  20. Segregated responses of mammary gland development and vaginal opening to prepubertal genistein exposure in Bscl2(-/-) female mice with lipodystrophy.

    PubMed

    Li, Rong; El Zowalaty, Ahmed E; Chen, Weiqin; Dudley, Elizabeth A; Ye, Xiaoqin

    2015-07-01

    Berardinelli-Seip congenital lipodystrophy 2-deficient (Bscl2(-/-)) mice recapitulate human BSCL2 disease with lipodystrophy. Bscl2-encoded seipin is detected in adipocytes and epithelium of mammary gland. Postnatal mammary gland growth spurt and vaginal opening signify pubertal onset in female mice. Bscl2(-/-) females have longer and dilated mammary gland ducts at 5-week old and delayed vaginal opening. Prepubertal exposure to 500ppm genistein diet increases mammary gland area and accelerates vaginal opening in both control and Bscl2(-/-) females. However, genistein treatment increases ductal length in control but not Bscl2(-/-) females. Neither prepubertal genistein treatment nor Bscl2-deficiency affects phospho-estrogen receptor α or progesterone receptor expression patterns in 5-week old mammary gland. Interestingly, Bscl2-deficiency specifically reduces estrogen receptor β expression in mammary gland ductal epithelium. In summary, Bscl2(-/-) females have accelerated postnatal mammary ductal development but delayed vaginal opening; they display segregated responses in mammary gland development and vaginal opening to prepubertal genistein treatment.

  1. TFAP2C Governs the Luminal Epithelial Phenotype in Mammary Development and Carcinogenesis

    PubMed Central

    Cyr, Anthony R; Kulak, Mikhail V.; Park, Jung M.; Bogachek, Maria V.; Spanheimer, Philip M.; Woodfield, George W.; White-Baer, Lola S.; O’Malley, Yunxia Q.; Sugg, Sonia L.; Olivier, Alicia K.; Zhang, Weizhou; Domann, Frederick E.; Weigel, Ronald J.

    2014-01-01

    Molecular subtypes of breast cancer are characterized by distinct patterns of gene expression that are predictive of outcome and response to therapy. The luminal breast cancer subtypes are defined by the expression of ER-alpha (ERα)-associated genes, many of which are directly responsive to the Transcription Factor Activator Protein 2C (TFAP2C). TFAP2C participates in a gene regulatory network controlling cell growth and differentiation during ectodermal development and regulating ESR1/ERα and other luminal cell-associated genes in breast cancer. TFAP2C has been established as a prognostic factor in human breast cancer, however, its role in the establishment and maintenance of the luminal cell phenotype during carcinogenesis and mammary gland development have remained elusive. Herein, we demonstrate a critical role for TFAP2C in maintaining the luminal phenotype in human breast cancer and in influencing the luminal cell phenotype during normal mammary development. Knockdown of TFAP2C in luminal breast carcinoma cells induced EMT with morphological and phenotypic changes characterized by a loss of luminal-associated gene expression and a concomitant gain of basal-associated gene expression. Conditional knockout of the mouse homolog of TFAP2C, Tcfap2c, in mouse mammary epithelium driven by MMTV-Cre promoted aberrant growth of the mammary tree leading to a reduction in the CD24hi/CD49fmid luminal cell population and concomitant gain of the CD24mid/CD49fhi basal cell population at maturity. Our results establish TFAP2C as a key transcriptional regulator for maintaining the luminal phenotype in human breast carcinoma. Furthermore, Tcfap2c influences development of the luminal cell type during mammary development. The data suggest that TFAP2C plays an important role in regulated luminal specific genes and may be a viable therapeutic target in breast cancer. PMID:24469049

  2. Paternal selenium deficiency but not supplementation during preconception alters mammary gland development and 7,12-dimethylbenz[a]anthracene-induced mammary carcinogenesis in female rat offspring.

    PubMed

    Guido, Luiza N; Fontelles, Camile C; Rosim, Mariana P; Pires, Vanessa C; Cozzolino, Silvia M F; Castro, Inar A; Bolaños-Jiménez, Francisco; Barbisan, Luis F; Ong, Thomas P

    2016-10-15

    Breast cancer is a global public health problem and accumulating evidence indicates early-life exposures as relevant factors in the disease risk determination. Recent studies have shown that paternal nutrition can influence offspring health including breast cancer risk. Selenium is a micronutrient with essential role in central aspects of embryogenesis, male fertility and cancer and that has been extensively studied as a chemopreventive agent in several breast cancer experimental models. Thus, we designed an animal study to evaluate whether paternal selenium deficiency or supplementation during preconception could affect the female offspring mammary gland development and breast cancer susceptibility. Male Sprague-Dawley rats were fed AIN93-G diet containing 0.15 ppm (control diet), 0.05 ppm (deficient diet) or 1 ppm (supplemented diet) of selenium for 9 weeks and mated with control female rats. Mammary carcinogenesis was induced with 7,12-dimethylbenz[a]anthracene (DMBA) in their female offspring. Paternal selenium deficiency increased the number of terminal end buds, epithelial elongation and cell proliferation in the mammary gland of the female rat offspring and these effects were associated with higher susceptibility to DMBA-induced mammary tumors (increased incidence and higher grade tumors). On the other hand, paternal selenium supplementation did not influence any of these parameters. These results highlight the importance of father's nutrition including selenium status as a relevant factor affecting daughter's breast cancer risk and paternal preconception as a potential developmental stage to start disease preventive strategies. PMID:27270969

  3. Flor-Essence? Herbal Tonic Promotes Mammary Tumor Development in Sprague Dawley Rats

    SciTech Connect

    Bennett, L; Montgomery, J; Steinberg, S; Kulp, K

    2004-01-28

    Background: Women who are diagnosed with breast cancer often self-administer complementary and alternative medicines to augment their conventional treatments, improve health, or prevent recurrence. Flor-Essence{reg_sign} Tonic is a complex mixture of herbal extracts used by cancer patients because of anecdotal evidence that it can treat or prevent disease. Methods: Female Sprague Dawley rats were given water or exposed to 3% or 6% Flor-Essence{reg_sign} beginning at one day of age. Mammary tumors were induced with a single oral 40 mg/kg/bw dose of dimethylbenz(a)anthracene at 50 days of age and sacrificed at 23 weeks. Rats were maintained on AIN-76A diet. Results: Control rats had palpable mammary tumor incidence of 51.0% at 19 weeks of age compared to 65.0% and 59.4% for the 3% and 6% Flor-Essence{reg_sign} groups respectively. Overall, no significant difference in time until first palpable tumor was detected among any of the groups. At necropsy, mammary tumor incidence was 82.5% for controls compared to 90.0% and 97.3% for rats consuming 3% and 6% Flor-Essence{reg_sign}, respectively. Mean mammary tumor multiplicity ({+-}SES) for the controls was 2.8 ({+-} 0.5) and statistically different from the 3% or 6% Flor- Essence{reg_sign} groups with 5.2 ({+-} 0.7), and 4.8 ({+-} 0.6), respectively (p{<=}0.01). As expected, the majority of isolated tumors were diagnosed as adenocarcinomas. Conclusions: Flor-Essence{reg_sign} can promote mammary tumor development in the Sprague Dawley rat model. This observation is contrary to widely available anecdotal evidence as well as the desire of the consumer that this commercially available herbal tonic will suppress and/or inhibit tumor growth.

  4. Alteration of mammary gland development and gene expression by in utero exposure to arsenic

    PubMed Central

    Parodi, Daniela A.; Greenfield, Morgan; Evans, Claire; Chichura, Anna; Alpaugh, Alexandra; Williams, James; Martin, Mary Beth

    2015-01-01

    Early life exposure to estrogens and estrogen like contaminants in the environment are thought to contribute to the early onset of puberty and consequently increase the risk of developing breast cancer in the exposed female. The results of this study show that in utero exposure to the metalloestrogen arsenite altered mammary gland development prior to its effect on puberty onset. In the prepubertal gland, in utero exposure resulted in an increase in the number of mammosphere-forming cells and an increase in branching, epithelial cells, and density. In the postpubertal gland, in utero exposure resulted in the overexpression of estrogen receptor-alpha (ERα) that was due to the increased and altered response of the ERα transcripts derived from exons O and OT to estradiol. These results suggest that, in addition to advancing puberty onset, in utero exposure to arsenite alters the pre- and postpubertal development of the mammary gland and possibly, the risk of developing breast cancer. PMID:25543096

  5. Modulation of Mammary Gland Development and Milk Production by Growth Hormone Expression in GH Transgenic Goats.

    PubMed

    Bao, Zekun; Lin, Jian; Ye, Lulu; Zhang, Qiang; Chen, Jianquan; Yang, Qian; Yu, Qinghua

    2016-01-01

    Mammary gland development during puberty and reconstruction during pregnancy and lactation is under the control of circulating endocrine hormones, such as growth hormone, which are released from the pituitary. In this study, we explored the influence of overexpression of growth hormone in the mammary gland on breast development and milk production in goats. Using transcriptome sequencing, we found that the number of highly expressed genes was greater in GH transgenic goats than non-transgenic goats. Furthermore, KEGG pathway analysis showed that the majority of the genes belonged to the MAPK signaling pathway and the ECM-receptor interaction pathway. The expression of genes related to breast development was further confirmed using qRT-PCR. Interestingly, both milk production and milk quality were increased. The results of these experiments imply that overexpression of growth hormone in the breast may stimulate breast development and enhances milk production by modulating alveolar cell proliferation or branching through the MAPK signaling pathway. PMID:27445863

  6. Modulation of Mammary Gland Development and Milk Production by Growth Hormone Expression in GH Transgenic Goats

    PubMed Central

    Bao, Zekun; Lin, Jian; Ye, Lulu; Zhang, Qiang; Chen, Jianquan; Yang, Qian; Yu, Qinghua

    2016-01-01

    Mammary gland development during puberty and reconstruction during pregnancy and lactation is under the control of circulating endocrine hormones, such as growth hormone, which are released from the pituitary. In this study, we explored the influence of overexpression of growth hormone in the mammary gland on breast development and milk production in goats. Using transcriptome sequencing, we found that the number of highly expressed genes was greater in GH transgenic goats than non-transgenic goats. Furthermore, KEGG pathway analysis showed that the majority of the genes belonged to the MAPK signaling pathway and the ECM-receptor interaction pathway. The expression of genes related to breast development was further confirmed using qRT-PCR. Interestingly, both milk production and milk quality were increased. The results of these experiments imply that overexpression of growth hormone in the breast may stimulate breast development and enhances milk production by modulating alveolar cell proliferation or branching through the MAPK signaling pathway. PMID:27445863

  7. Modulation of Mammary Gland Development and Milk Production by Growth Hormone Expression in GH Transgenic Goats.

    PubMed

    Bao, Zekun; Lin, Jian; Ye, Lulu; Zhang, Qiang; Chen, Jianquan; Yang, Qian; Yu, Qinghua

    2016-01-01

    Mammary gland development during puberty and reconstruction during pregnancy and lactation is under the control of circulating endocrine hormones, such as growth hormone, which are released from the pituitary. In this study, we explored the influence of overexpression of growth hormone in the mammary gland on breast development and milk production in goats. Using transcriptome sequencing, we found that the number of highly expressed genes was greater in GH transgenic goats than non-transgenic goats. Furthermore, KEGG pathway analysis showed that the majority of the genes belonged to the MAPK signaling pathway and the ECM-receptor interaction pathway. The expression of genes related to breast development was further confirmed using qRT-PCR. Interestingly, both milk production and milk quality were increased. The results of these experiments imply that overexpression of growth hormone in the breast may stimulate breast development and enhances milk production by modulating alveolar cell proliferation or branching through the MAPK signaling pathway.

  8. Effects of body weight and nutrition on histological mammary development in Holstein heifers.

    PubMed

    Daniels, K M; McGilliard, M L; Meyer, M J; Van Amburgh, M E; Capuco, A V; Akers, R M

    2009-02-01

    Our objective was to determine the effects of rate of gain and body weight (BW) on development of the mammary parenchyma. Mammary tissue samples were collected from heifers (n = 72) reared on 1 of 2 dietary treatments (restricted, 650 g/d of daily gain; or elevated, 950 g/d of daily gain) and slaughtered at 100, 150, 200, 250, 300, or 350 kg of BW. Mammary samples were excised, preserved, prepared for histology, and stained with hematoxylin and eosin. Digital images of tissue sections were captured for analysis. Tissue areas occupied by the interlobular and intralobular stroma, epithelium, and lumen were measured (mum(2)). The numbers of epithelial and luminal structures per image were tabulated to measure the complexity of ductal development. Mean percentages of mammary parenchyma occupied by the interlobular stroma, epithelium, lumen, and intralobular stroma were 29, 20, 7, and 43%, respectively. Percentage of area occupied by the intralobular stroma was affected by BW and was lower for 100-kg heifers compared with heifers 200 kg and heavier (33 +/- 4 vs. 46 +/- 4), but the percentage of area occupied by other tissue elements did not differ by BW or treatment, nor was there an interaction. However, the numbers of both epithelial (8.3 +/- 4 vs. 47 +/- 4) and luminal-containing (6 +/- 4 vs. 38 +/- 4) structures per image increased markedly between 100 and 350 kg of BW, irrespective of diet. For heifers slaughtered between 100 and 350 kg of BW, alterations in the rate of gain between 650 and 950 g/d, accomplished by feeding varying amounts of the same diet, had no significant effect on tissue characteristics or the pattern of mammary parenchymal development. These data emphasize the importance of BW and age in determining developmental characteristics of the heifer mammary parenchyma and suggest that the rate of gain per se has a minimal impact on histological development, and thus do not support the hypothesis that rate of gain has a direct negative impact on

  9. Mammary Gland Growth Factors: Roles in Normal Development and in Cancer

    PubMed Central

    Hynes, Nancy E.; Watson, Christine J.

    2010-01-01

    Normal development of the mammary gland proceeds via interactions between the epithelium and the mesenchyme that start during embryogenesis and continue during pubertal outgrowth and differentiation. The function of specific peptide growth factors that bind members of the receptor tyrosine kinase family and the cytokine receptor family are required at each stage. In many cases the peptides are produced in one compartment and act on receptors in the other compartment. One of the striking differences between normal development and cancer is the loss of this cross-talk. Mammary tumor cells often produce a peptide and express the receptor on the same cell leading to autocrine activation of signaling pathways, a mechanism that is characteristic for cancer cells. We will discuss different peptides in the context of normal development and cancer in this review. PMID:20554705

  10. Promoting effects of Chinese pangolin and wild pink medicines on the mammary gland development in immature mice.

    PubMed

    Bayin, Jiragara; Matsumoto, Mitsuharu; Islam, Mohammad Saiful; Yabuki, Akira; Kanouchi, Hiroaki; Oka, Tatsuzo; Nishinakagawa, Hayao

    2009-10-01

    The effects of the mixture of crude aqueous extracts from Chinese pangolin and wild pink (C+P), traditional Chinese medicine, on the proliferation and differentiation of mammary gland epithelium in intact and ovariectomized immature mice were investigated by light and electron microscopy and BrdU immunohistochemistry. Although there were no significant differences in mammary gland fat pad and parenchyma areas between the intact experimental groups, the numbers of duct branchings and buds were significantly larger in the C+W treated mice than in the control mice. The ratio of BrdU immunopositive cells to total epithelial cells was higher in C+W treated intact mice. Ultrastructurally, epithelial cells of the mammary buds and ducts possessed an oval and lucent nucleus, and ribosomes increased in number or developed to a greater degree in C+W treated intact mice than in the control mice. Conversely, there were no significant differences in any measurements of mammary gland between the experimental groups of ovariectomized mice. BrdU immunoreactive cells were never seen and the ultrastructure of mammary epihelial cells indicated the inactive cell phase in both ovariectomied mice. In comparison between the intact and overiectomized mice, the mammary fat pad area was larger in the ovariectomized mice than in the intact mice, although another four measurements were larger in the intact groups. These observations suggest that administration with C+W could promote the development of mammary glands via ovary in immature mice. PMID:19887738

  11. Promoting effects of Chinese pangolin and wild pink medicines on the mammary gland development in immature mice.

    PubMed

    Bayin, Jiragara; Matsumoto, Mitsuharu; Islam, Mohammad Saiful; Yabuki, Akira; Kanouchi, Hiroaki; Oka, Tatsuzo; Nishinakagawa, Hayao

    2009-10-01

    The effects of the mixture of crude aqueous extracts from Chinese pangolin and wild pink (C+P), traditional Chinese medicine, on the proliferation and differentiation of mammary gland epithelium in intact and ovariectomized immature mice were investigated by light and electron microscopy and BrdU immunohistochemistry. Although there were no significant differences in mammary gland fat pad and parenchyma areas between the intact experimental groups, the numbers of duct branchings and buds were significantly larger in the C+W treated mice than in the control mice. The ratio of BrdU immunopositive cells to total epithelial cells was higher in C+W treated intact mice. Ultrastructurally, epithelial cells of the mammary buds and ducts possessed an oval and lucent nucleus, and ribosomes increased in number or developed to a greater degree in C+W treated intact mice than in the control mice. Conversely, there were no significant differences in any measurements of mammary gland between the experimental groups of ovariectomized mice. BrdU immunoreactive cells were never seen and the ultrastructure of mammary epihelial cells indicated the inactive cell phase in both ovariectomied mice. In comparison between the intact and overiectomized mice, the mammary fat pad area was larger in the ovariectomized mice than in the intact mice, although another four measurements were larger in the intact groups. These observations suggest that administration with C+W could promote the development of mammary glands via ovary in immature mice.

  12. Effects of Perfluorooctanoic Acid on Mouse Mammary Gland Development and Differentiation Resulting from Cross-Foster and Restricted Gestational Exposures

    EPA Science Inventory

    The adverse consequences of developmental exposures to perfluorooctanoic acid (PFOA) have been established, and include impaired development of the offspring mammary gland (MG). However, the relationship between the timing or route of exposure, and the phenotypic consequences in ...

  13. Models of breast morphogenesis based on localization of stem cells in the developing mammary lobule.

    PubMed

    Honeth, Gabriella; Schiavinotto, Tommaso; Vaggi, Federico; Marlow, Rebecca; Kanno, Tokuwa; Shinomiya, Ireneusz; Lombardi, Sara; Buchupalli, Bharath; Graham, Rosalind; Gazinska, Patrycja; Ramalingam, Vernie; Burchell, Joy; Purushotham, Anand D; Pinder, Sarah E; Csikasz-Nagy, Attila; Dontu, Gabriela

    2015-04-14

    Characterization of normal breast stem cells is important for understanding their role in breast development and in breast cancer. However, the identity of these cells is a subject of controversy and their localization in the breast epithelium is not known. In this study, we utilized a novel approach to analyze the morphogenesis of mammary lobules, by combining one-dimensional theoretical models and computer-generated 3D fractals. Comparing predictions of these models with immunohistochemical analysis of tissue sections for candidate stem cell markers, we defined distinct areas where stem cells reside in the mammary lobule. An increased representation of stem cells was found in smaller, less developed lobules compared to larger, more mature lobules, with marked differences in the gland of nulliparous versus parous women and that of BRCA1/2 mutation carriers versus non-carriers.

  14. Models of breast morphogenesis based on localization of stem cells in the developing mammary lobule.

    PubMed

    Honeth, Gabriella; Schiavinotto, Tommaso; Vaggi, Federico; Marlow, Rebecca; Kanno, Tokuwa; Shinomiya, Ireneusz; Lombardi, Sara; Buchupalli, Bharath; Graham, Rosalind; Gazinska, Patrycja; Ramalingam, Vernie; Burchell, Joy; Purushotham, Anand D; Pinder, Sarah E; Csikasz-Nagy, Attila; Dontu, Gabriela

    2015-04-14

    Characterization of normal breast stem cells is important for understanding their role in breast development and in breast cancer. However, the identity of these cells is a subject of controversy and their localization in the breast epithelium is not known. In this study, we utilized a novel approach to analyze the morphogenesis of mammary lobules, by combining one-dimensional theoretical models and computer-generated 3D fractals. Comparing predictions of these models with immunohistochemical analysis of tissue sections for candidate stem cell markers, we defined distinct areas where stem cells reside in the mammary lobule. An increased representation of stem cells was found in smaller, less developed lobules compared to larger, more mature lobules, with marked differences in the gland of nulliparous versus parous women and that of BRCA1/2 mutation carriers versus non-carriers. PMID:25818813

  15. Perinatal Environmental Exposures Affect Mammary Development, Function, and Cancer Risk in Adulthood*

    PubMed Central

    Fenton, Suzanne E.; Reed, Casey; Newbold, Retha R.

    2012-01-01

    Puberty is an important transition that enables reproduction of mammalian species. Precocious puberty, specifically early thelarche (the appearance of breast “buds”), in girls of multiple ethnic backgrounds is a major health problem in the United States and other countries. The cause for a continued decrease in the age of breast development in girls is unknown, but environmental factors likely play a major role. Laboratory and epidemiological studies have identified several individual environmental factors that affect breast development, but further progress is needed. Current research needs include increased attention to and recording of prenatal and neonatal environmental exposures, testing of marketed chemicals for effects on the mammary gland, and understanding of the mammary gland–specific mechanisms that are altered by chemicals. Such research is required to halt the increasing trend toward puberty at earlier ages. PMID:22017681

  16. Prenatal Bisphenol A exposure delays the development of the male rat mammary gland.

    PubMed

    Kass, Laura; Durando, Milena; Altamirano, Gabriela A; Manfroni-Ghibaudo, Gisela E; Luque, Enrique H; Muñoz-de-Toro, Mónica

    2015-07-01

    Our aims were to evaluate whether exposure to Bisphenol A (BPA) modifies the development of the male rat mammary gland (MG) and to evaluate whether this modification is gender specific. From gestational day 9, pregnant rats were exposed either subcutaneously to 0, 25 or 250μg BPA/kgbw/day until parturition or orally to 0 and 64μg BPA/kgbw/day until weaning. MG development was analyzed on postnatal days (PND) 5, 15 and 30. On PND30, steroid hormone receptor expression and mammary growth were also evaluated. On PND30, the exposure to 64BPA and 250BPA induced a delay in male MG development, evidenced by reduced ductal growth, decreased number of terminal structures and lower expression of androgen receptor (AR). In contrast, female mammary ductal growth was altered only by 250BPA. Regardless of the administration route and length of the exposure period, BPA induced a delay in MG development and modified AR expression in prepubertal male rats.

  17. Humanization of the mouse mammary gland.

    PubMed

    Wronski, A; Arendt, L M; Kuperwasser, Charlotte

    2015-01-01

    Although mouse models have provided invaluable information on the mechanisms of mammary gland development, anatomical and developmental differences between human and mice limit full understanding of this fundamental process. Humanization of the mouse mammary gland by injecting immortalized human breast stromal cells into the cleared murine mammary fat pad enables the growth and development of human mammary epithelial cells or tissue. This facilitates the characterization of human mammary gland development or tumorigenesis by utilizing the mouse mammary fat pad. Here we describe the process of isolating human mammary stromal and epithelial cells as well as their introduction into the mammary fat pads of immunocompromised mice.

  18. A hybrid agent-based model of the developing mammary terminal end bud.

    PubMed

    Butner, Joseph D; Chuang, Yao-Li; Simbawa, Eman; Al-Fhaid, A S; Mahmoud, S R; Cristini, Vittorio; Wang, Zhihui

    2016-10-21

    Mammary gland ductal elongation is spearheaded by terminal end buds (TEBs), where populations of highly proliferative cells are maintained throughout post-pubertal organogenesis in virgin mice until the mammary fat pad is filled by a mature ductal tree. We have developed a hybrid multiscale agent-based model to study how cellular differentiation pathways, cellular proliferation capacity, and endocrine and paracrine signaling play a role during development of the mammary gland. A simplified cellular phenotypic hierarchy that includes stem, progenitor, and fully differentiated cells within the TEB was implemented. Model analysis finds that mammary gland development was highly sensitive to proliferation events within the TEB, with progenitors likely undergoing 2-3 proliferation cycles before transitioning to a non-proliferative phenotype, and this result is in agreement with our previous experimental work. Endocrine and paracrine signaling were found to provide reliable ductal elongation rate regulation, while variations in the probability a new daughter cell will be of a proliferative phenotype were seen to have minimal effects on ductal elongation rates. Moreover, the distribution of cellular phenotypes within the TEB was highly heterogeneous, demonstrating significant allowable plasticity in possible phenotypic distributions while maintaining biologically relevant growth behavior. Finally, simulation results indicate ductal elongation rates due to cellular proliferation within the TEB may have a greater sensitivity to upstream endocrine signaling than endothelial to stromal paracrine signaling within the TEB. This model provides a useful tool to gain quantitative insights into cellular population dynamics and the effects of endocrine and paracrine signaling within the pubertal terminal end bud.

  19. Abnormal Mammary Development in 129:STAT1-Null Mice is Stroma-Dependent.

    PubMed

    Chen, Jane Q; Mori, Hidetoshi; Cardiff, Robert D; Trott, Josephine F; Hovey, Russell C; Hubbard, Neil E; Engelberg, Jesse A; Tepper, Clifford G; Willis, Brandon J; Khan, Imran H; Ravindran, Resmi K; Chan, Szeman R; Schreiber, Robert D; Borowsky, Alexander D

    2015-01-01

    Female 129:Stat1-null mice (129S6/SvEvTac-Stat1(tm1Rds) homozygous) uniquely develop estrogen-receptor (ER)-positive mammary tumors. Herein we report that the mammary glands (MG) of these mice have altered growth and development with abnormal terminal end buds alongside defective branching morphogenesis and ductal elongation. We also find that the 129:Stat1-null mammary fat pad (MFP) fails to sustain the growth of 129S6/SvEv wild-type and Stat1-null epithelium. These abnormalities are partially reversed by elevated serum progesterone and prolactin whereas transplantation of wild-type bone marrow into 129:Stat1-null mice does not reverse the MG developmental defects. Medium conditioned by 129:Stat1-null epithelium-cleared MFP does not stimulate epithelial proliferation, whereas it is stimulated by medium conditioned by epithelium-cleared MFP from either wild-type or 129:Stat1-null females having elevated progesterone and prolactin. Microarrays and multiplexed cytokine assays reveal that the MG of 129:Stat1-null mice has lower levels of growth factors that have been implicated in normal MG growth and development. Transplanted 129:Stat1-null tumors and their isolated cells also grow slower in 129:Stat1-null MG compared to wild-type recipient MG. These studies demonstrate that growth of normal and neoplastic 129:Stat1-null epithelium is dependent on the hormonal milieu and on factors from the mammary stroma such as cytokines. While the individual or combined effects of these factors remains to be resolved, our data supports the role of STAT1 in maintaining a tumor-suppressive MG microenvironment.

  20. A hybrid agent-based model of the developing mammary terminal end bud.

    PubMed

    Butner, Joseph D; Chuang, Yao-Li; Simbawa, Eman; Al-Fhaid, A S; Mahmoud, S R; Cristini, Vittorio; Wang, Zhihui

    2016-10-21

    Mammary gland ductal elongation is spearheaded by terminal end buds (TEBs), where populations of highly proliferative cells are maintained throughout post-pubertal organogenesis in virgin mice until the mammary fat pad is filled by a mature ductal tree. We have developed a hybrid multiscale agent-based model to study how cellular differentiation pathways, cellular proliferation capacity, and endocrine and paracrine signaling play a role during development of the mammary gland. A simplified cellular phenotypic hierarchy that includes stem, progenitor, and fully differentiated cells within the TEB was implemented. Model analysis finds that mammary gland development was highly sensitive to proliferation events within the TEB, with progenitors likely undergoing 2-3 proliferation cycles before transitioning to a non-proliferative phenotype, and this result is in agreement with our previous experimental work. Endocrine and paracrine signaling were found to provide reliable ductal elongation rate regulation, while variations in the probability a new daughter cell will be of a proliferative phenotype were seen to have minimal effects on ductal elongation rates. Moreover, the distribution of cellular phenotypes within the TEB was highly heterogeneous, demonstrating significant allowable plasticity in possible phenotypic distributions while maintaining biologically relevant growth behavior. Finally, simulation results indicate ductal elongation rates due to cellular proliferation within the TEB may have a greater sensitivity to upstream endocrine signaling than endothelial to stromal paracrine signaling within the TEB. This model provides a useful tool to gain quantitative insights into cellular population dynamics and the effects of endocrine and paracrine signaling within the pubertal terminal end bud. PMID:27475843

  1. Stem and progenitor cell division kinetics during postnatal mouse mammary gland development.

    PubMed

    Giraddi, Rajshekhar R; Shehata, Mona; Gallardo, Mercedes; Blasco, Maria A; Simons, Benjamin D; Stingl, John

    2015-01-01

    The cycling properties of mammary stem and progenitor cells is not well understood. To determine the division properties of these cells, we administered synthetic nucleosides for varying periods of time to mice at different stages of postnatal development and monitored the rate of uptake of these nucleosides in the different mammary cell compartments. Here we show that most cell division in the adult virgin gland is restricted to the oestrogen receptor-expressing luminal cell lineage. Our data also demonstrate that the oestrogen receptor-expressing, milk and basal cell subpopulations have telomere lengths and cell division kinetics that are not compatible with these cells being hierarchically organized; instead, our data indicate that in the adult homeostatic gland, each cell type is largely maintained by its own restricted progenitors. We also observe that transplantable stem cells are largely quiescent during oestrus, but are cycling during dioestrus when progesterone levels are high.

  2. The T-box transcription factors TBX2 and TBX3 in mammary gland development and breast cancer.

    PubMed

    Douglas, Nataki C; Papaioannou, Virginia E

    2013-06-01

    TBX2 and TBX3, closely related members of the T-box family of transcription factor genes, are expressed in mammary tissue in both humans and mice. Ulnar mammary syndrome (UMS), an autosomal dominant disorder caused by mutations in TBX3, underscores the importance of TBX3 in human breast development, while abnormal mammary gland development in Tbx2 or Tbx3 mutant mice provides models for experimental investigation. In addition to their roles in mammary development, aberrant expression of TBX2 and TBX3 is associated with breast cancer. TBX2 is preferentially amplified in BRCA1/2-associated breast cancers and TBX3 overexpression has been associated with advanced stage disease and estrogen-receptor-positive breast tumors. The regulation of Tbx2 and Tbx3 and the downstream targets of these genes in development and disease are not as yet fully elucidated. However, it is clear that the two genes play unique, context-dependent roles both in mammary gland development and in mammary tumorigenesis.

  3. Stromal regulation of embryonic and postnatal mammary epithelial development and differentiation.

    PubMed

    Howard, Beatrice A; Lu, Pengfei

    2014-01-01

    The stroma, which is composed of supporting cells and connective tissue, comprises a large component of the local microenvironment of many epithelial cell types, and influences several fundamental aspects of cell behaviour through both tissue interactions and niche regulation. The significance of the stroma in development and disease has been increasingly recognised. Whereas normal stroma is essential for various developmental processes during vertebrate organogenesis, it can be deregulated and become abnormal, which in turn can initiate or promote a disease process, including cancer. The mouse mammary gland has emerged in recent years as an excellent model system for understanding stromal function in both developmental and cancer biology. Here, we take a systematic approach and focus on the dynamic interactions that the stroma engages with the epithelium during mammary specification, cell differentiation, and branching morphogenesis of both the embryonic and postnatal development of the mammary gland. Similar stromal-epithelial interactions underlie the aetiology of breast cancer, making targeting the cancer stroma an increasingly important and promising therapeutic strategy to pursue for breast cancer treatment.

  4. ErbB/EGF signaling and EMT in mammary development and breast cancer.

    PubMed

    Hardy, Katharine M; Booth, Brian W; Hendrix, Mary J C; Salomon, David S; Strizzi, Luigi

    2010-06-01

    Activation of the ErbB family of receptor tyrosine kinases via cognate Epidermal Growth Factor (EGF)-like peptide ligands constitutes a major group of related signaling pathways that control proliferation, survival, angiogenesis and metastasis of breast cancer. In this respect, clinical trials with various ErbB receptor blocking antibodies and specific tyrosine kinase inhibitors have proven to be partially efficacious in the treatment of this heterogeneous disease. Induction of an embryonic program of epithelial-to-mesenchymal transition (EMT) in breast cancer, whereupon epithelial tumor cells convert to a more mesenchymal-like phenotype, facilitates the migration, intravasation, and extravasation of tumor cells during metastasis. Breast cancers which exhibit properties of EMT are highly aggressive and resistant to therapy. Activation of ErbB signaling can regulate EMT-associated invasion and migration in normal and malignant mammary epithelial cells, as well as modulating discrete stages of mammary gland development. The purpose of this review is to summarize current information regarding the role of ErbB signaling in aspects of EMT that influence epithelial cell plasticity during mammary gland development and tumorigenesis. How this information may contribute to the improvement of therapeutic approaches in breast cancer will also be addressed.

  5. Runx2 is a novel regulator of mammary epithelial cell fate in development and breast cancer

    PubMed Central

    Best, Sarah; Ledger, Anita; Mooney, Anne-Marie; Ferguson, Alison; Shore, Paul; Swarbrick, Alexander; Ormandy, Christopher J; Simpson, Peter T; Carroll, Jason S; Visvader, Jane; Naylor, Matthew J

    2014-01-01

    Regulators of differentiated cell fate can offer targets for managing cancer development and progression. Here we identify Runx2 as a new regulator of epithelial cell fate in mammary gland development and breast cancer. Runx2 is expressed in the epithelium of pregnant mice in a strict temporally and hormonally-regulated manner. During pregnancy, Runx2 genetic deletion impaired alveolar differentiation in a manner that disrupted alveolar progenitor cell populations. Conversely, exogenous transgenic expression of Runx2 in mammary epithelial cells blocked milk production, suggesting that the decrease in endogenous Runx2 observed late in pregnancy is necessary for full differentiation. In addition, overexpression of Runx2 drove EMT-like changes in normal mammary epithelial cells, while Runx2 deletion in basal breast cancer cells inhibited cellular phenotypes associated with tumorigenesis. Notably, loss of Runx2 expression increased tumor latency and enhanced overall survival in a mouse model of breast cancer, with Runx2-deficient tumors exhibiting reduced cell proliferation. Together, our results establish a novel function for Runx2 in breast cancer that may offer a novel generalized route for therapeutic interventions. PMID:25056120

  6. Cytokine networks that mediate epithelial cell-macrophage crosstalk in the mammary gland: implications for development and cancer.

    PubMed

    Sun, Xuan; Ingman, Wendy V

    2014-07-01

    Dynamic interactions between the hormone responsive mammary gland epithelium and surrounding stromal macrophage populations are critical for normal development and function of the mammary gland. Macrophages are versatile cells capable of diverse roles in mammary gland development and maintenance of homeostasis, and their function is highly dependent on signals within the local cytokine microenvironment. The mammary epithelium secretes a number of cytokines, including colony stimulating factor 1 (CSF1), transforming growth factor beta 1 (TGFB1), and chemokine ligand 2 (CCL2) that affect the abundance, phenotype and function of macrophages. However, aberrations in these interactions have been found to increase the risk of tumour formation, and utilisation of stromal macrophage support by tumours can increase the invasive and metastatic potential of the cancer. Studies utilising genetically modified mouse models have shed light on the significance of epithelial cell-macrophage crosstalk, and the cytokines that mediate this communication, in mammary gland development and tumourigenesis. This article reviews the current status of our understanding of the roles of epithelial cell-derived cytokines in mammary gland development and cancer, with a focus on the crosstalk between epithelial cells and the local macrophage population.

  7. Cripto-1 ablation disrupts alveolar development in the mouse mammary gland through a progesterone receptor-mediated pathway.

    PubMed

    Klauzinska, Malgorzata; McCurdy, David; Rangel, Maria Cristina; Vaidyanath, Arun; Castro, Nadia P; Shen, Michael M; Gonzales, Monica; Bertolette, Daniel; Bianco, Caterina; Callahan, Robert; Salomon, David S; Raafat, Ahmed

    2015-11-01

    Cripto-1, a member of the epidermal growth factor-Cripto-1/FRL-1/Cryptic family, is critical for early embryonic development. Together with its ligand Nodal, Cripto-1 has been found to be associated with the undifferentiated status of mouse and human embryonic stem cells. Several studies have clearly shown that Cripto-1 is involved in regulating branching morphogenesis and epithelial-mesenchymal transition of the mammary gland both in vitro and in vivo and together with the cofactor GRP78 is critical for the maintenance of mammary stem cells ex vivo. Our previous studies showed that mammary-specific overexpression of human Cripto-1 exhibited dramatic morphological alterations in nulliparous mice mammary glands. The present study shows a novel mechanism for Cripto-1 regulation of mammary gland development through direct effects on progesterone receptor expression and pathways regulated by progesterone in the mammary gland. We demonstrate a strict temporal regulation of mouse Cripto-1 (mCripto-1) expression that occurs during mammary gland development and a stage-specific function of mCripto-1 signaling during mammary gland development. Our data suggest that Cripto-1, like the progesterone receptor, is not required for the initial ductal growth but is essential for subsequent side branching and alveologenesis during the initial stages of pregnancy. Dissection of the mechanism by which this occurs indicates that mCripto-1 activates receptor activator NF-κB/receptor activator NF-κB ligand, and NF-κB signaling pathways.

  8. Detection of Expressional Changes Induced by Intrauterine Growth Restriction in the Developing Rat Mammary Gland via Exploratory Pathways Analysis

    PubMed Central

    Beinder, Lea; Faehrmann, Nina; Wachtveitl, Rainer; Winterfeld, Ilona; Hartner, Andrea; Menendez-Castro, Carlos; Rauh, Manfred; Ruebner, Matthias; Huebner, Hanna; Noegel, Stephanie C.; Doerr, Helmuth G.; Rascher, Wolfgang; Fahlbusch, Fabian B.

    2014-01-01

    Background Intrauterine growth restriction (IUGR) is thought to lead to fetal programming that in turn contributes to developmental changes of many organs postnatally. There is evidence that IUGR is a risk factor for the development of metabolic and cardiovascular disease later in life. A higher incidence of breast cancer was also observed after IUGR. This could be due to changes in mammary gland developmental pathways. We sought to characterise IUGR-induced alterations of the complex pathways of mammary development at the level of the transcriptome in a rat model of IUGR, using pathways analysis bioinformatics. Methodology/Principal Findings We analysed the mammary glands of Wistar rats with IUGR induced by maternal low protein (LP) diet at the beginning (d21) and the end (d28) of pubertal ductal morphogenesis. Mammary glands of the LP group were smaller in size at d28, however did not show morphologic changes. We identified multiple differentially expressed genes in the mammary gland using Agilent SurePrint arrays at d21 and d28. In silico analysis was carried out using Ingenuity Pathways Analysis. In mammary gland tissue of LP rats at d21 of life a prominent upregulation of WT1 and CDKN1A (p21) expression was observed. Differentially regulated genes were associated with the extracellular regulated kinase (ERK)-1/-2 pathway. Western Blot analysis showed reduced levels of phosphorylated ERK-1/-2 in the mammary glands of the LP group at d21. To identify possible changes in circulating steroid levels, serum LC-Tandem mass-spectrometry was performed. LP rats showed higher serum progesterone levels and an increased corticosterone/dehydrocorticosterone-ratio at d28. Conclusions/Significance Our data obtained from gene array analysis support the hypothesis that IUGR influences pubertal development of the rat mammary gland. We identified prominent differential regulation of genes and pathways for factors regulating cell cycle and growth. Moreover, we detected new

  9. Modulation of mammary gland development in prepubertal male rats exposed to genistein and methoxychlor.

    PubMed

    You, Li; Sar, Madhabananda; Bartolucci, Erika J; McIntyre, Barry S; Sriperumbudur, Rajagopal

    2002-04-01

    The estrogenic isoflavone genistein is a common dietary component that has been shown to affect reproductive development in experimental animals at high doses. The objective of the present study was to examine interactions of genistein and the hormonally active pesticide methoxychlor on mammary gland development in juvenile rats. Timed-pregnant Sprague-Dawley rats were fed a soy- and alfalfa-free diet containing different combinations of genistein (300 and 800 ppm) and methoxychlor (800 ppm). Rats were fed these diets starting on gestation day (GD)1 and continuing through pregnancy and lactation until postnatal day (PND) 22, when the pups were killed. Inguinal mammary glands from both female and male pups were processed as whole-mount preparations for morphometric analysis. The total glandular area and the numbers of branch points, lateral buds, and terminal end buds in the male rats were found to be significantly greater in the groups exposed to methoxychlor than those exposed to genistein only. These effects were not observed in the female rats. In the male rats, methoxychlor had the most prominent effect on elongating the glandular ducts, while genistein enhanced the ductile branching. The 2 compounds in combination promoted the development of alveolar-lobular structure, an effect not observed with either compound alone. Immunostaining for proliferating cell nuclear antigen revealed a high percentage of immunopositive cells in the mammary epithelia of the males exposed to methoxychlor and genistein (800 ppm) compared to the controls. While no significant changes in serum levels of mammotrophic hormones were detected, increased immunostaining for insulin-like growth factor-1 receptor, estrogen receptor alpha, and progesterone receptor in the genistein + methoxychlor group suggested that local factors involved in regulating mammary growth may have played a role in propagating the endocrine effects of these two compounds. These results indicated that the mammary

  10. Overexpression of miR-30b in the Developing Mouse Mammary Gland Causes a Lactation Defect and Delays Involution

    PubMed Central

    Laubier, Johann; Passet, Bruno; Vilotte, Marthe; Castille, Johan; Laloë, Denis; Polyte, Jacqueline; Bouet, Stéphan; Jaffrézic, Florence; Cribiu, Edmond-Paul; Vilotte, Jean-Luc; Le Provost, Fabienne

    2012-01-01

    Background MicroRNA (miRNA) are negative regulators of gene expression, capable of exerting pronounced influences upon the translation and stability of mRNA. They are potential regulators of normal mammary gland development and of the maintenance of mammary epithelial progenitor cells. This study was undertaken to determine the role of miR-30b on the establishment of a functional mouse mammary gland. miR-30b is a member of the miR-30 family, composed of 6 miRNA that are highly conserved in vertebrates. It has been suggested to play a role in the differentiation of several cell types. Methodology/Principal Findings The expression of miR-30b was found to be regulated during mammary gland development. Transgenic mice overexpressing miR-30b in mammary epithelial cells were used to investigate its role. During lactation, mammary histological analysis of the transgenic mice showed a reduction in the size of alveolar lumen, a defect of the lipid droplets and a growth defect of pups fed by transgenic females. Moreover some mammary epithelial differentiated structures persisted during involution, suggesting a delay in the process. The genes whose expression was affected by the overexpression of miR-30b were characterized by microarray analysis. Conclusion/Significance Our data suggests that miR-30b is important for the biology of the mammary gland and demonstrates that the deregulation of only one miRNA could affect lactation and involution. PMID:23029204

  11. The dynamics of murine mammary stem/progenitor cells

    PubMed Central

    DONG, Qiaoxiang; SUN, Lu-Zhe

    2014-01-01

    The stem/progenitor cells in the murine mammary gland are a highly dynamic population of cells that are responsible for ductal elongation in puberty, homeostasis maintenance in adult, and lobulo-alveolar genesis during pregnancy. In recent years understanding the epithelial cell hierarchy within the mammary gland is becoming particularly important as these different stem/progenitor cells were perceived to be the cells of origin for various subtypes of breast cancer. Although significant advances have been made in enrichment and isolation of stem/progenitor cells by combinations of antibodies against cell surface proteins together with flow cytometry, and in identification of stem/progenitor cells with multi-lineage differentiation and self-renewal using mammary fat pad reconstitution assay and in vivo genetic labeling technique, a clear understanding of how these different stem/progenitors are orchestrated in the mammary gland is still lacking. Here we discuss the different in vivo and in vitro methods currently available for stem/progenitor identification, their associated caveats, and a possible new hierarchy model to reconcile various putative stem/progenitor cell populations identified by different research groups. PMID:25580105

  12. A Novel Nectin-mediated Cell Adhesion Apparatus That Is Implicated in Prolactin Receptor Signaling for Mammary Gland Development.

    PubMed

    Kitayama, Midori; Mizutani, Kiyohito; Maruoka, Masahiro; Mandai, Kenji; Sakakibara, Shotaro; Ueda, Yuki; Komori, Takahide; Shimono, Yohei; Takai, Yoshimi

    2016-03-11

    Mammary gland development is induced by the actions of various hormones to form a structure consisting of collecting ducts and milk-secreting alveoli, which comprise two types of epithelial cells known as luminal and basal cells. These cells adhere to each other by cell adhesion apparatuses whose roles in hormone-dependent mammary gland development remain largely unknown. Here we identified a novel cell adhesion apparatus at the boundary between the luminal and basal cells in addition to desmosomes. This apparatus was formed by the trans-interaction between the cell adhesion molecules nectin-4 and nectin-1, which were expressed in the luminal and basal cells, respectively. Nectin-4 of this apparatus further cis-interacted with the prolactin receptor in the luminal cells to enhance the prolactin-induced prolactin receptor signaling for alveolar development with lactogenic differentiation. Thus, a novel nectin-mediated cell adhesion apparatus regulates the prolactin receptor signaling for mammary gland development. PMID:26757815

  13. A Novel Nectin-mediated Cell Adhesion Apparatus That Is Implicated in Prolactin Receptor Signaling for Mammary Gland Development.

    PubMed

    Kitayama, Midori; Mizutani, Kiyohito; Maruoka, Masahiro; Mandai, Kenji; Sakakibara, Shotaro; Ueda, Yuki; Komori, Takahide; Shimono, Yohei; Takai, Yoshimi

    2016-03-11

    Mammary gland development is induced by the actions of various hormones to form a structure consisting of collecting ducts and milk-secreting alveoli, which comprise two types of epithelial cells known as luminal and basal cells. These cells adhere to each other by cell adhesion apparatuses whose roles in hormone-dependent mammary gland development remain largely unknown. Here we identified a novel cell adhesion apparatus at the boundary between the luminal and basal cells in addition to desmosomes. This apparatus was formed by the trans-interaction between the cell adhesion molecules nectin-4 and nectin-1, which were expressed in the luminal and basal cells, respectively. Nectin-4 of this apparatus further cis-interacted with the prolactin receptor in the luminal cells to enhance the prolactin-induced prolactin receptor signaling for alveolar development with lactogenic differentiation. Thus, a novel nectin-mediated cell adhesion apparatus regulates the prolactin receptor signaling for mammary gland development.

  14. The consequence of level of nutrition on heifer ovarian and mammary development.

    PubMed

    Freetly, H C; Vonnahme, K A; McNeel, A K; Camacho, L E; Amundson, O L; Forbes, E D; Lents, C A; Cushman, R A

    2014-12-01

    Replacing cows in the herd is second only to nutrition as the single greatest input cost in cow/calf beef production. The increased availability of cereal grains for feeding livestock has allowed replacement heifers to enter the production system at younger ages. Many heifer development programs feed to ensure heifers reach puberty before the time that they are mated to calve at 2 yr of age. Nutrition level during development has been associated with altered milk production and stayability. We hypothesized that heifers exposed to a lower nutrition level during the peripubertal period would have less methylation of the DNA in the mammary gland and ovarian cortex. We also hypothesized that the ovarian reserve would decrease in heifers fed for rapid growth compared to heifers fed for slow growth during puberty. At 257±1 d of age, heifers in the Stair-Step treatment (n=6) received 157 kcal ME/BW kg0.75 for 84 d and heifers in the Conventional treatment (n=6) were offered 228 kcal ME/BW kg0.75. At d 84, heifers were fed for an additional 83 d. Stair-Step heifers were offered 277 kcal ME/BW kg0.75, and heifers on the Conventional treatment received 228 kcal ME/BW kg0.75. Mammary weights (P=0.43), capillary area density (P=0.74), and capillary surface density (P=0.18) did not differ between treatments and neither did alveolar number (P=0.55) and alveolar density (P=0.49). Reproductive tract weights (P=0.69) and ovarian weight (P=0.68) and ovarian size (P>0.75) did not differ between treatments. In histological sections, Stair-Step heifers had more primordial follicles than Conventional heifers (P=0.02), but primary (P=0.59) and secondary (P=0.15) follicles did not differ. Global methylation of parenchymal tissue (P=0.82), mammary fat pad (P=0.45), and ovarian cortex (P=0.14) did not differ between treatments. Anterior pituitary weight did not differ between treatments (P=0.16). Our hypothesis that modifying peripubertal nutrition modifies global methylation of the

  15. The transcriptional repressor Blimp1 is expressed in rare luminal progenitors and is essential for mammary gland development.

    PubMed

    Ahmed, Mohammed I; Elias, Salah; Mould, Arne W; Bikoff, Elizabeth K; Robertson, Elizabeth J

    2016-05-15

    Mammary gland morphogenesis depends on a tight balance between cell proliferation, differentiation and apoptosis, to create a defined functional hierarchy within the epithelia. The limited availability of stem cell/progenitor markers has made it challenging to decipher lineage relationships. Here, we identify a rare subset of luminal progenitors that express the zinc finger transcriptional repressor Blimp1, and demonstrate that this subset of highly clonogenic luminal progenitors is required for mammary gland development. Conditional inactivation experiments using K14-Cre and WAPi-Cre deleter strains revealed essential functions at multiple developmental stages. Thus, Blimp1 regulates proliferation, apoptosis and alveolar cell maturation during puberty and pregnancy. Loss of Blimp1 disrupts epithelial architecture and lumen formation both in vivo and in three-dimensional (3D) primary cell cultures. Collectively, these results demonstrate that Blimp1 is required to maintain a highly proliferative luminal subset necessary for mammary gland development and homeostasis.

  16. Influence of chronic prolactin suppression during puberty on the development of dimethylbenz(a)anthracene-induced mammary tumors (41163). [Rats

    SciTech Connect

    Cohen, L.A.

    1981-06-01

    In order to assess the effect of early prolactin suppression on the subsequent development of dimethylbenz(a)anthracene (DMBA)-induced mammary cancers, the dopamine agonist, CB-154, was chronically administered to female Sprague-Dawley rats from Day 35 to Day 50 of age. DMBA was then administered and tumor development assessed over a 25-week period. It was found that animals treated with CB-154 exhibited decreased tumor incidence, a longer latent period, and fewer tumors/animal, when compared to vehicle controls. These results are consistent with the hypothesis that the sensitivity of the mammary gland to polycyclic aromatic hydrocarbon (PAH) carcinogenesis is determined by the level of differentiation of the gland at the time of carcinogen administration. Accordingly, perturbations in prolactin secretion patterns, early in life, may accelerate or retard the differentiation of the mammary gland thereby rendering it less susceptible to the carcinogenic effects of PAH.

  17. The transcriptional repressor Blimp1 is expressed in rare luminal progenitors and is essential for mammary gland development

    PubMed Central

    Ahmed, Mohammed I.; Mould, Arne W.; Bikoff, Elizabeth K.

    2016-01-01

    ABSTRACT Mammary gland morphogenesis depends on a tight balance between cell proliferation, differentiation and apoptosis, to create a defined functional hierarchy within the epithelia. The limited availability of stem cell/progenitor markers has made it challenging to decipher lineage relationships. Here, we identify a rare subset of luminal progenitors that express the zinc finger transcriptional repressor Blimp1, and demonstrate that this subset of highly clonogenic luminal progenitors is required for mammary gland development. Conditional inactivation experiments using K14-Cre and WAPi-Cre deleter strains revealed essential functions at multiple developmental stages. Thus, Blimp1 regulates proliferation, apoptosis and alveolar cell maturation during puberty and pregnancy. Loss of Blimp1 disrupts epithelial architecture and lumen formation both in vivo and in three-dimensional (3D) primary cell cultures. Collectively, these results demonstrate that Blimp1 is required to maintain a highly proliferative luminal subset necessary for mammary gland development and homeostasis. PMID:27190036

  18. Development and validation of a dedicated microarray for the evaluation of bovine mammary gland health status and milk quality.

    PubMed

    Broccolo, Francesco; Maran, Valentina; Oggioni, Massimo; Matteoli, Barbara; Greppi, Gianfranco; Ceccherini-Nelli, Luca; Fusetti, Lisa

    2013-07-01

    The purpose of this study was the output and set up of the milk array, a dedicated array designed to investigate the expression levels of many genes involved in cow mammary gland inflammation and milk production regulation. First, a new targeted genes panel was selected. Successively, the microarray reliability was examined by yellow and dye swap experiments using the normal and mastitic mammary gland samples from the same cow. The sensitivity and reliability were evaluated using different amounts of the same mastitic mammary gland RNA: a good linear regression (R (2) = 0.758) was obtained also using only 3 μg of RNA. We used both reverse transcriptase RT-qPCR and the microarray to analyze 100 bovine genes (96 known to be involved in inflammation and milk production regulation and four housekeeping genes) in pooled total RNA isolated from tissue samples. All genes were detectable by RT-qPCR and microarray: a good mean correlation coefficient over all samples of 0.885 showed that both methods were similarly well suited to analyze gene expression in these samples. This report describes the development of small DNA microarray of fully defined genes suitable for analysis of expression of many genes involved in cow mammary gland inflammation and milk production regulation; this platform will prove useful as diagnostic tool prototype to perform a more in-depth analysis of the milk quality and mammary glands health status. PMID:23224854

  19. Evaluating chemical effects on mammary gland development: A critical need in disease prevention.

    PubMed

    Osborne, Gwendolyn; Rudel, Ruthann; Schwarzman, Megan

    2015-07-01

    Although understanding the environmental factors that contribute to breast cancer could improve disease prevention, standard chemical testing protocols do not adequately evaluate chemicals' effects on breast development. Evidence suggests: (1) mammary gland (MG) development is a complex process that extends from gestation through fetal and neonatal growth, puberty, and pregnancy; (2) altered MG development can increase the risk of breast cancer and other adverse outcomes; and (3) chemical exposures during susceptible windows of development may alter the MG in ways that increase risk for later disease. Together, these highlight the need to better understand the complex relationship between exposure to endocrine disrupting compounds (EDCs) and the alterations in MG morphology and gene expression that ultimately increase disease risk. Changing guideline toxicity testing studies to incorporate perinatal exposures and MG whole mounts would generate critical knowledge about the effects of EDCs on the MG and could ultimately inform disease prevention.

  20. Feeding a higher plane of nutrition and providing exogenous estrogen increases mammary gland development in Holstein heifer calves.

    PubMed

    Geiger, A J; Parsons, C L M; Akers, R M

    2016-09-01

    Feeding heifers a higher plane of nutrition postweaning but before puberty can negatively affect mammary gland development and future milk yield. However, enhanced nutrition preweaning may promote development and future production. Our objectives were to determine the effects of enhanced feeding preweaning and exogenous estrogen immediately postweaning on mammary gland development and the composition of the mammary parenchyma (PAR) and mammary fat pad (MFP). Thirty-six Holstein heifer calves (<1 wk old) were reared on 1 of 2 dietary treatments for 8 wk: (1) a restricted milk replacer fed at 0.45 kg/d (R; 20% crude protein, 20% fat), or (2) an enhanced milk replacer fed at 1.13 kg/d (EH; 28% crude protein, 25% fat). Upon weaning, calves from each diet (n=6) were given either a placebo or estrogen implant for 2 wk, creating 4 treatments: R, R + estrogen (R-E2), EH, and EH + estrogen (EH-E2). Calves were housed individually with ad libitum access to water. Starter feeding began at wk 5 and was balanced between treatments. Udders were evaluated by palpation and physical measurements weekly. Subsets of calves were killed at weaning (n=6 per diet) and at the conclusion of the trial (n=6 per treatment). Udders were removed, dissected, and weighed. At wk 8, EH calves had longer front and rear teats. Providing estrogen to EH calves increased the length of rear teats during wk 9 and 10. Enhanced-fed calves had 5.2-fold more trimmed mammary gland mass than R calves. Providing estrogen to EH calves further increased mammary gland weight. Masses of PAR and MFP were markedly greater for EH calves than for R calves (e.g., 7.3-fold greater PAR tissue). Estrogen increased the mass of both PAR and MFP in EH calves. Feeding a higher plane of nutrition increased total protein, DNA, and fat in the MFP and total protein and DNA in the PAR. Dual-energy x-ray absorptiometry estimates of mammary fat mass were highly correlated with biochemical analyses of fat content. From histological

  1. Feeding a higher plane of nutrition and providing exogenous estrogen increases mammary gland development in Holstein heifer calves.

    PubMed

    Geiger, A J; Parsons, C L M; Akers, R M

    2016-09-01

    Feeding heifers a higher plane of nutrition postweaning but before puberty can negatively affect mammary gland development and future milk yield. However, enhanced nutrition preweaning may promote development and future production. Our objectives were to determine the effects of enhanced feeding preweaning and exogenous estrogen immediately postweaning on mammary gland development and the composition of the mammary parenchyma (PAR) and mammary fat pad (MFP). Thirty-six Holstein heifer calves (<1 wk old) were reared on 1 of 2 dietary treatments for 8 wk: (1) a restricted milk replacer fed at 0.45 kg/d (R; 20% crude protein, 20% fat), or (2) an enhanced milk replacer fed at 1.13 kg/d (EH; 28% crude protein, 25% fat). Upon weaning, calves from each diet (n=6) were given either a placebo or estrogen implant for 2 wk, creating 4 treatments: R, R + estrogen (R-E2), EH, and EH + estrogen (EH-E2). Calves were housed individually with ad libitum access to water. Starter feeding began at wk 5 and was balanced between treatments. Udders were evaluated by palpation and physical measurements weekly. Subsets of calves were killed at weaning (n=6 per diet) and at the conclusion of the trial (n=6 per treatment). Udders were removed, dissected, and weighed. At wk 8, EH calves had longer front and rear teats. Providing estrogen to EH calves increased the length of rear teats during wk 9 and 10. Enhanced-fed calves had 5.2-fold more trimmed mammary gland mass than R calves. Providing estrogen to EH calves further increased mammary gland weight. Masses of PAR and MFP were markedly greater for EH calves than for R calves (e.g., 7.3-fold greater PAR tissue). Estrogen increased the mass of both PAR and MFP in EH calves. Feeding a higher plane of nutrition increased total protein, DNA, and fat in the MFP and total protein and DNA in the PAR. Dual-energy x-ray absorptiometry estimates of mammary fat mass were highly correlated with biochemical analyses of fat content. From histological

  2. Expression of Autoactivated Stromelysin-1 in Mammary Glands of Transgenic Mice Leads to a Reactive Stroma During Early Development

    SciTech Connect

    Thomasset, N.; Lochter, A.; Sympson, C.J.; Lund, L.R.; Williams, D.R.; Behrendtsen, O.; Werb, Z.; Bissell, M.J.

    1998-04-24

    Extracellular matrix and extracellular matrix-degrading matrix metalloproteinases play a key role in interactions between the epithelium and the mesenchyme during mammary gland development and disease. In patients with breast cancer, the mammary mesenchyme undergoes a stromal reaction, the etiology of which is unknown. We previously showed that targeting of an autoactivating mutant of the matrix metalloproteinase stromelysin-1 to mammary epithelia of transgenic mice resulted in reduced mammary function during pregnancy and development of preneoplastic and neoplastic lesions. Here we examine the cascade of alterations before breast tumor formation in the mammary gland stroma once the expression of the stromelysin-1 transgene commences. Beginning in postpubertal virgin animals, low levels of transgene expression in mammary epithelia led to increased expression of endogenous stromelysin-1 in stromal fibroblasts and up-regulation of other matrix metalloproteinases, without basement membrane disruption. These changes were accompanied by the progressive development of a compensatory reactive stroma, characterized by increased collagen content and vascularization in glands from virgin mice. This remodeling of the gland affected epithelial-mesenchymal communication as indicated by inappropriate expression of tenascin-C starting by day 6 of pregnancy. This, together with increased transgene expression, led to basement membrane disruption starting by day 15 of pregnancy. We propose that the highly reactive stroma provides a prelude to breast epithelial tumors observed in these animals. Epithelial development depends on an exquisite series of inductive and instructive interactions between the differentiating epithelium and the mesenchymal (stromal) compartment. The epithelium, which consists of luminal and myoepithelial cells, is separated from the stroma by a basement membrane (BM), which plays a central role in mammary gland homeostasis and gene expression. In vivo, stromal

  3. From milk to malignancy: the role of mammary stem cells in development, pregnancy and breast cancer

    PubMed Central

    Tiede, Benjamin; Kang, Yibin

    2011-01-01

    Adult stem cells of the mammary gland (MaSCs) are a highly dynamic population of cells that are responsible for the generation of the gland during puberty and its expansion during pregnancy. In recent years significant advances have been made in understanding how these cells are regulated during these developmentally important processes both in humans and in mice. Understanding how MaSCs are regulated is becoming a particularly important area of research, given that they may be particularly susceptible targets for transformation in breast cancer. Here, we summarize the identification of MaSCs, how they are regulated and the evidence for their serving as the origins of breast cancer. In particular, we focus on how changes in MaSC populations may explain both the increased risk of developing aggressive ER/PR(−) breast cancer shortly after pregnancy and the long-term decreased risk of developing ER/PR(+) tumors. PMID:21243011

  4. Tamoxifen impairs prepubertal mammary development and alters expression of estrogen receptor α (ESR1) and progesterone receptors (PGR).

    PubMed

    Tucker, H L M; Parsons, C L M; Ellis, S; Rhoads, M L; Akers, R M

    2016-01-01

    Research has shown that prepubertal heifers experience allometric mammary growth that is influenced by the ovaries. Our purpose was to determine the role of estrogen in prepubertal mammary gland development. Sixteen Holstein calves were randomly assigned to 1 of 2 treatment groups: tamoxifen-injected (TAM) or control (CON). Calves were administered the antiestrogen tamoxifen (0.3 mg kg(1) d(1)) or placebo from 28 to 120 d of age. At 120 d, calves were euthanized and udders removed. Weight and DNA content of trimmed parenchymal tissue were halved (P ≤ 0.0001) in TAM compared with CON calves. Parenchymal samples from 3 zones of the left rear mammary gland (lower, middle, and outer regions) were processed for immunohistochemical staining for estrogen receptor α (ESR1) and progesterone receptor (PGR), Ki67-positive cells, and 5-bromo-2'-deoxyuridine label retaining cells (LRCs). Overall, neither the percentage nor location within the epithelial tissue layer of either ESR1- or PGR-positive cells was impacted by TAM treatment. However, image analysis indicated a 6.2-fold lower (P = 0.0001) level of ESR1 protein expression in TAM calves. Similarly, messenger RNA expression of ESR1 was also reduced (P = 0.0001) in TAM heifers. In contrast, expression of PGR protein was greater by 43% (P = 0.03) in TAM calves, but messenger RNA expression did not differ between treatments. Overall, TAM calves had a higher (P ≤ 0.03) percentage and density (cells per tissue area) of Ki67-positive cells. Irrespective of treatment, there were also more Ki67-labeled cells in the outer zones of the mammary gland (P ≤ 0.001). We were able to effectively use multispectral imaging to identify positive cells and quantify the expression of ESR1 and PGR protein. We also identified and counted the proportion of label retaining cells (LCR) (putative epithelial stem cells). We noted an overall 2.9-fold greater number of LRCs in TAM heifers and more LRCs in the outer sampling zones. This suggests

  5. Mammary gland development and response to prenatal atrazine exposure in the Sprague Dawley and Long-Evans rats.

    EPA Science Inventory

    Mammary gland (MG) tumor development in Sprague Dawley (SD) rats is increased by longterm dietary exposure to the chlorotriazine herbicide atrazine (ATR). ATR is proposed to cause these changes in the adult SD rat by altering hormonally-regulated estrous cyclicity. In Long-Evans...

  6. EXPOSURE PARAMETERS FOR DELAYED PUBERTY AND MAMMARY GLAND DEVELOPMENT IN LONG-EVANS RATS EXPOSED IN UTERO TO ATRAZINE

    EPA Science Inventory

    Exposure Parameters For Delayed Puberty And Mammary Gland Development In Long-Evans Rats Exposed In Utero To Atrazine

    Jennifer L. Rayner1 and Suzanne E. Fenton2

    1 UNC-Chapel Hill, DESE, Chapel Hill, NC, and 2 RTD, USEPA, NHEERL/ORD, RTP,NC

    Prenatal exposure ...

  7. HORMONAL CONTROL OF OVARIAN FUNCTION FOLLOWING CHLOROTRIAZINE EXPOSURE: EFFECT ON REPRODUCTIVE FUNCTION AND MAMMARY GLAND TUMOR DEVELOPMENT

    EPA Science Inventory

    Hormonal Control of Ovarian Function Following Chlorotriazine Exposure: Effect on Reproductive Function and Mammary Gland Tumor Development.

    Ralph L. Cooper, Susan C. Laws, Michael G. Narotsky, Jerome M. Goldman, and Tammy E. Stoker

    Abstract
    The studies review...

  8. A functional connection between pRB and transforming growth factor beta in growth inhibition and mammary gland development.

    PubMed

    Francis, Sarah M; Bergsied, Jacqueline; Isaac, Christian E; Coschi, Courtney H; Martens, Alison L; Hojilla, Carlo V; Chakrabarti, Subrata; Dimattia, Gabriel E; Khoka, Rama; Wang, Jean Y J; Dick, Frederick A

    2009-08-01

    Transforming growth factor beta (TGF-beta) is a crucial mediator of breast development, and loss of TGF-beta-induced growth arrest is a hallmark of breast cancer. TGF-beta has been shown to inhibit cyclin-dependent kinase (CDK) activity, which leads to the accumulation of hypophosphorylated pRB. However, unlike other components of TGF-beta cytostatic signaling, pRB is thought to be dispensable for mammary development. Using gene-targeted mice carrying subtle missense changes in pRB (Rb1(DeltaL) and Rb1(NF)), we have discovered that pRB plays a critical role in mammary gland development. In particular, Rb1 mutant female mice have hyperplastic mammary epithelium and defects in nursing due to insensitivity to TGF-beta growth inhibition. In contrast with previous studies that highlighted the inhibition of cyclin/CDK activity by TGF-beta signaling, our experiments revealed that active transcriptional repression of E2F target genes by pRB downstream of CDKs is also a key component of TGF-beta cytostatic signaling. Taken together, our work demonstrates a unique functional connection between pRB and TGF-beta in growth control and mammary gland development.

  9. EXPOSURE PARAMETERS NECESSARY FOR DELAYED PUBERTY AND MAMMARY GLAND DEVELOPMENT IN LONG-EVANS RATS EXPOSED IN UTERO TO ATRAZINE

    EPA Science Inventory

    Exposure Parameters Necessary For Delayed Puberty And Mammary Gland Development In Long-Evans Rats Exposed In Utero To Atrazine

    Jennifer L. Rayner1, 2, Carmen Wood2, and Suzanne E. Fenton2

    1 Department of Environmental Sciences and Engineering, School of Public Heal...

  10. In-silico QTL mapping of postpubertal mammary ductal development in the mouse uncovers potential human breast cancer risk loci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic background plays a dominant role in mammary gland development and breast cancer (BrCa). Despite this, the role of genetics is only partially understood. This study used strain-dependent variation in an inbred mouse mapping panel, to identify quantitative trait loci (QTL) underlying structura...

  11. Three dimensional multiphoton imaging of fresh and whole mount developing mouse mammary glands

    PubMed Central

    2013-01-01

    using the META detector for spectral emission scanning. Backward scattered or reflected SHG (SHG-B) was detected using a conventional confocal detector with maximum aperture and forward scattered or transmitted SHG (SHG-F) detected using a non-descanned detector. Results We show here that the developing mammary gland is encased in a thin but dense layer of collagen fibers. Sparse collagen layers are also interspersed between stromal layers of fat cells surrounding TEBs. At the margins, TEBs approach the outer collagen layer but do not penetrate it. Abnormal mammary glands from an HAI-1 transgenic FVB mouse model were found to contain TEBs with abnormal pockets of cells forming extra lumens and zones of continuous lateral bud formation interspersed with sparse collagen fibers. Parameters influencing live imaging and imaging of fixed unstained and Carmine Alum stained whole mounts were evaluated. Artifacts induced by light scattering of GFP and Carmine Alum signals from epithelial cells were identified in live tissue as primarily due to fat cells and in whole mount tissue as due to dense Carmine Alum staining of epithelium. Carmine Alum autofluorescence was detected at excitation wavelengths from 750 to 950 nm with a peak of emission at 623 nm (~602-656 nm). Images of Carmine Alum fluorescence differed dramatically at emission wavelengths of 565–615 nm versus 650–710 nm. In the latter, a mostly epithelial (nuclear) visualization of Carmine Alum predominates. Autofluorescence with a peak emission of 495 nm was derived from the fixed and processed tissue itself as it was present in the unstained whole mount. Contribution of autofluorescence to the image decreases with increasing laser excitation wavelengths. SHG-B versus SHG-F signals revealed collagen fibers and could be found within single fibers, or in different fibers within the same layer. These differences presumably reflected different states of collagen fiber maturation. Loss of SHG signals from layer to

  12. Elf5 inhibits the epithelial-mesenchymal transition in mammary gland development and breast cancer metastasis by transcriptionally repressing Snail2.

    PubMed

    Chakrabarti, Rumela; Hwang, Julie; Andres Blanco, Mario; Wei, Yong; Lukačišin, Martin; Romano, Rose-Anne; Smalley, Kirsten; Liu, Song; Yang, Qifeng; Ibrahim, Toni; Mercatali, Laura; Amadori, Dino; Haffty, Bruce G; Sinha, Satrajit; Kang, Yibin

    2012-11-01

    The epithelial-mesenchymal transition (EMT) is a complex process that occurs during organogenesis and in cancer metastasis. Despite recent progress, the molecular pathways connecting the physiological and pathological functions of EMT need to be better defined. Here we show that the transcription factor Elf5, a key regulator of mammary gland alveologenesis, controls EMT in both mammary gland development and metastasis. We uncovered this role for Elf5 through analyses of Elf5 conditional knockout animals, various in vitro and in vivo models of EMT and metastasis, an MMTV-neu transgenic model of mammary tumour progression and clinical breast cancer samples. Furthermore, we demonstrate that Elf5 suppresses EMT by directly repressing the transcription of Snail2, a master regulator of mammary stem cells and a known inducer of EMT. These findings establish Elf5 not only as a key cell lineage regulator during normal mammary gland development, but also as a suppressor of EMT and metastasis in breast cancer.

  13. GANP protein encoded on human chromosome 21/mouse chromosome 10 is associated with resistance to mammary tumor development.

    PubMed

    Kuwahara, Kazuhiko; Yamamoto-Ibusuki, Mutsuko; Zhang, Zhenhuan; Phimsen, Suchada; Gondo, Naomi; Yamashita, Hiroko; Takeo, Toru; Nakagata, Naomi; Yamashita, Daisuke; Fukushima, Yoshimi; Yamamoto, Yutaka; Iwata, Hiroji; Saya, Hideyuki; Kondo, Eisaku; Matsuo, Keitaro; Takeya, Motohiro; Iwase, Hirotaka; Sakaguchi, Nobuo

    2016-04-01

    Human chromosome 21 is known to be associated with the high risk of hematological malignancy but with resistance to breast cancer in the study of Down syndrome. In human cancers, we previously observed the significant alterations of the protein expression encoded by the ganp/MCM3AP gene on human chromosome 21q22.3. Here, we investigated GANP protein alterations in human breast cancer samples (416 cases) at various stages by immunohistochemical analysis. This cohort study clearly showed that expression of GANP is significantly decreased in human breast cancer cases with poor prognosis as an independent risk factor (relapse-free survival, hazard ratio = 2.37, 95% confidence interval, 1.27-4.42, P = 0.007 [univariate analysis]; hazard ratio = 2.70, 95% confidence interval, 1.42-5.13, P = 0.002 [multivariate analysis]). To investigate whether the altered GANP expression is associated with mammary tumorigenesis, we created mutant mice that were conditionally deficient in the ganp/MCM3AP gene using wap-cre recombinase transgenic mice. Mammary gland tumors occurred at a very high incidence in female mammary gland-specific GANP-deficient mice after severe impairment of mammary gland development during pregnancy. Moreover, tumor development also occurred in female post parous GANP-heterodeficient mice. GANP has a significant role in the suppression of DNA damage caused by estrogen in human breast cancer cell lines. These results indicated that the GANP protein is associated with breast cancer resistance. PMID:26749495

  14. Mammary gland development of dairy heifers fed diets containing increasing levels of metabolisable protein: metabolisable energy.

    PubMed

    Albino, Ronan L; Marcondes, Marcos I; Akers, Robert M; Detmann, Edenio; Carvalho, Bruno C; Silva, Tadeu E

    2015-02-01

    This study was conducted to evaluate the development of the mammary gland in Holstein heifers subjected to different dietary metabolisable protein (MP): metabolisable energy (ME) ratios. Twenty-five Holstein heifers (initial body weight (BW) 213±13·5 kg and initial average age 7·8±0·5 months) were divided into five treatments. The treatments were designed to provide MP:ME ratios equal to 33, 38, 43, 48, and 53 g of MP per Mcal of ME. All diets were formulated to have the same energy content (2·6 Mcal ME/kg dry matter). Actual MP:ME ratios were 36·2, 40·2, 46·2, 47·1, and 50·8 g MP/Mcal ME. The experiment was conducted in a randomised block design, while considering initial BW as a blocking factor to evaluate pre- and post-pubertal periods. Block effect was not observed for all variables evaluated; hence it was considered that the diets had the same influence both on pre- and post-pubertal phases. Dry matter and nutrient intake did not change between treatments, excepting protein intake and digestibility. Serum concentrations of insulin-like growth factor 1 increased linearly across treatments. Changes in the pixel brightness of mammary gland ultrasound images, which are associated with lipid content, were significantly influenced by MP:ME ratios in the diet of heifers that were subjected to accelerated growth rates. It is not recommended to use diets of less than 38 g MP/Mcal ME in diets to heifers allowed to gain more than 1 kg/d. PMID:25592631

  15. Flor-Essence® herbal tonic does not inhibit estrogen receptor negative mammary tumor development in a transgenic mouse model

    PubMed Central

    Bennett, L. Michelle; Montgomery, Jennifer L.; Collins, N. Keith; Steinberg, Seth M.; Kulp, Kristen S.

    2012-01-01

    Women who are diagnosed with breast cancer often self-administer complementary and alternative medicines to augment their conventional treatments, improve health, or prevent recurrence. Flor-Essence® herbal tonic is a complex mixture of eight herbal extracts used by cancer patients because of anecdotal evidence that it can treat or prevent disease. In this study four experimental groups of female MMTV-Neu mice were left untreated or treated with 3% Flor-Essence® in utero, from birth until 5 weeks of age, or throughout their lifetime. Palpable mammary tumor incidence and body weight was determined weekly for each group. The mice were sacrificed at 28 weeks of age and mammary tumors were enumerated to determine average tumor incidence and multiplicity for each group. Female mice exposed to Flor-Essence® herbal tonic in utero weighed significantly more than the control group (p < 0.001). The average tumor incidence and tumor multiplicity in the experimental mice treated with Flor-Essence® herbal tonic did not differ from the control animals. Flor-Essence® does not inhibit mammary tumor incidence or mammary tumor multiplicity in MMTV-Neu transgenic mice. Flor-Essence® exposure in utero causes increased body weight in experimental animals. This conclusion challenges widely available anecdotal information as well as the hopes of the consumer that this product will inhibit or suppress tumor development. Lay Abstract Flor-Essence® herbal tonic is a complex mixture of eight herbal extracts often used by women with breast cancer in hopes that it will help cure disease or prevent recurrence. There is currently very little scientific data to support or refute its self-administration. We tested whether Flor-Essence® would influence tumor development in the mammary glands of a mouse model of Her2/neu breast cancer. The tonic was given at different life stages to determine if timing of the exposure influenced the response to treatment. This report shows that Flor

  16. Perfluorooctanoic acid effects on ovaries mediate its inhibition of peripubertal mammary gland development in Balb/c and C57Bl/6 mice

    EPA Science Inventory

    Exposure to perfluorooctanoic acid (PFOA), a synthetic perfluorinated compound and an agonist of peroxisomes proliferator-activated receptor α (PPARα), causes stunted mouse mammary gland development in various developmental stages. However, the underlying mechanisms remain poorly...

  17. PTEN and p53 cross-regulation induced by soy isoflavone genistein promotes mammary epithelial cell cycle arrest and lobuloalveolar differentiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tumor suppressors PTEN and p53 are closely related to the pathogenesis of breast cancer, yet pathway-specific mechanisms underlying their participation in mediating the protective actions of dietary bioactive components on breast cancer risk are poorly understood. We recently showed that dietary...

  18. Effects of the plant extract silymarin on prolactin concentrations, mammary gland development, and oxidative stress in gestating gilts.

    PubMed

    Farmer, C; Lapointe, J; Palin, M-F

    2014-07-01

    The impacts of supplementing the diet of gestating gilts twice daily with 4 g of the plant extract silymarin on circulating hormonal concentrations, oxidative status, mammary development, and mammary gene expression at the end of gestation were determined. Gilts were fed conventional diets during gestation and on d 90 they were assigned as controls (CTL; n = 16) or treated (TRT; n = 17) animals. Treatment consisted of providing 4 g of silymarin twice daily until d 110, at which time all gilts were slaughtered to collect mammary tissue for compositional analyses and measures of gene expression and oxidative status, and liver and corpora lutea for measures of oxidative stress variables. Blood samples for hormonal assays and evaluation of oxidative stress biomarkers were obtained on d 89, 94, and 109 of gestation. Silymarin increased (P = 0.05) circulating concentrations of prolactin over all samples in the repeated in time analysis. In separate analyses for each sampling time, prolactin concentrations in TRT gilts tended (P < 0.10) to be greater than in CTL gilts on d 94 of gestation. Repeated in time analysis also revealed that silymarin reduced (P ≤ 0.05) plasmatic accumulation of biomarkers of oxidative damage to protein (protein carbonyls) between d 89 and 109. There was no effect (P > 0.10) of treatment on progesterone, estradiol, leptin, or 8-hydroxy-2'-deoxyguanosine concentrations. Percent fat in mammary parenchyma was greater (P ≤ 0.05), percent protein was lesser (P ≤ 0.05), and concentrations of both RNA (P ≤ 0.01) and DNA (P < 0.05) were lesser in TRT than CTL gilts. Mammary parenchyma from TRT gilts had lower (P ≤ 0.05) mRNA abundance for STAT5A and leptin and tended to have lower (P ≤ 0.10) abundance for STAT5B than CTL gilts. Silymarin reduced (P ≤ 0.001) protein carbonyls concentrations in liver of TRT gilts. No effect of treatment was observed on antioxidant gene expression and enzymatic activities in liver samples while total

  19. Pre-irradiation of mouse mammary gland stimulates cancer cell migration and development of lung metastases

    PubMed Central

    Bouchard, G; Bouvette, G; Therriault, H; Bujold, R; Saucier, C; Paquette, B

    2013-01-01

    Background: In most patients with breast cancer, radiotherapy induces inflammation that is characterised by an increase of promigratory factors in healthy tissues surrounding the tumour. However, their role in the emergence of the migration phenotype and formation of metastases is still unclear. Methods: A single mammary gland of BALB/c mice was irradiated with four doses of 6 Gy given at a 24-h interval. After the last session of irradiation, treated and control mammary glands were either collected for quantification of promigratory and proinflammatory factors or were implanted with fluorescent ubiquitination-based cell cycle indicator (FUCCI)-expressing mouse mammary cancer D2A1 cells. The migration of cancer cells in the mammary glands was monitored by optical imaging. On day 21, mammary tumours and lungs were collected for histology analyses and the quantification of metastases. Results: Pre-irradiation of the mammary gland increased by 1.8-fold the migration of cancer cells, by 2-fold the quantity of circulating cancer cells and by 2.4-fold the number of lung metastases. These adverse effects were associated with the induction of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2). Conclusion: The emergence of the metastasis phenotype is believed to be associated with the accumulation of mutations in cancer cells. Our results suggest an alternative mechanism based on promigratory factors from irradiated mammary glands. In clinic, the efficiency of radiotherapy could be improved by anti-inflammatory agents that would prevent the stimulation of cancer cell migration induced by radiation. PMID:24002607

  20. Genetic suppression reveals DNA repair-independent antagonism between BRCA1 and COBRA1 in mammary gland development.

    PubMed

    Nair, Sreejith J; Zhang, Xiaowen; Chiang, Huai-Chin; Jahid, Md Jamiul; Wang, Yao; Garza, Paula; April, Craig; Salathia, Neeraj; Banerjee, Tapahsama; Alenazi, Fahad S; Ruan, Jianhua; Fan, Jian-Bing; Parvin, Jeffrey D; Jin, Victor X; Hu, Yanfen; Li, Rong

    2016-01-01

    The breast cancer susceptibility gene BRCA1 is well known for its function in double-strand break (DSB) DNA repair. While BRCA1 is also implicated in transcriptional regulation, the physiological significance remains unclear. COBRA1 (also known as NELF-B) is a BRCA1-binding protein that regulates RNA polymerase II (RNAPII) pausing and transcription elongation. Here we interrogate functional interaction between BRCA1 and COBRA1 during mouse mammary gland development. Tissue-specific deletion of Cobra1 reduces mammary epithelial compartments and blocks ductal morphogenesis, alveologenesis and lactogenesis, demonstrating a pivotal role of COBRA1 in adult tissue development. Remarkably, these developmental deficiencies due to Cobra1 knockout are largely rescued by additional loss of full-length Brca1. Furthermore, Brca1/Cobra1 double knockout restores developmental transcription at puberty, alters luminal epithelial homoeostasis, yet remains deficient in homologous recombination-based DSB repair. Thus our genetic suppression analysis uncovers a previously unappreciated, DNA repair-independent function of BRCA1 in antagonizing COBRA1-dependent transcription programme during mammary gland development. PMID:26941120

  1. ERBB3/HER3 and ERBB2/HER2 duet in mammary development and breast cancer.

    PubMed

    Stern, David F

    2008-06-01

    ERBB3/HER3 is one of the four members of the epidermal growth factor receptor (ERBB) family. It is activated by binding to ligands Neuregulin-1 and Neuregulin-2. Since ERBB3 lacks intrinsic kinase activity, signal transduction occurs through formation of heterodimers with EGFR, ERBB2, and ERBB4. ERBB3 is a signaling specialist since it has six binding sites for the p85 SH2 adapter subunit of phosphoinositide 3' kinases. These lipid kinases coordinate regulation of metabolism, cell size, proliferation, survival, and angiogenesis. Not surprisingly, ERBB3 signaling has been linked to cancer etiology and progression. In breast cancer, the partnership of ERBB2 and ERBB3 may be crucial for the aggressive properties of cancers with ERBB2 amplification, and may contribute to pre-existing and acquired resistance to therapy. This partnership creates opportunities for improving efficacy of ERBB-targeted pharmaceuticals, by interfering with coupling of ERBB2 to ERBB3 through dimerization inhibitors, and by use of therapeutic compounds that target AKT-dependent pathways activated through ERBB3. Additional therapeutic opportunities may be identified through better understanding of how ERBBs are regulated and deployed in normal mammary gland processes. Work using mouse models has identified the main processes regulated by each of the four ERBBs, which has practical implications in understanding breast cancer etiology, and eventual development of better prognostic, predictive, and therapeutic tools.

  2. Identification of reliable reference genes for qRT-PCR studies of the developing mouse mammary gland

    PubMed Central

    van de Moosdijk, Anoeska Agatha Alida; van Amerongen, Renée

    2016-01-01

    Cell growth and differentiation are often driven by subtle changes in gene expression. Many challenges still exist in detecting these changes, particularly in the context of a complex, developing tissue. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) allows relatively high-throughput evaluation of multiple genes and developmental time points. Proper quantification of gene expression levels by qRT-PCR requires normalization to one or more reference genes. Traditionally, these genes have been selected based on their presumed “housekeeping” function, with the implicit assumption that they are stably expressed over the entire experimental set. However, this is rarely tested empirically. Here we describe the identification of novel reference genes for the mouse mammary gland based on their stable expression in published microarray datasets. We compared eight novel candidate reference genes (Arpc3, Clock, Ctbp1, Phf7, Prdx1, Sugp2, Taf11 and Usp7) to eight traditional ones (18S, Actb, Gapdh, Hmbs, Hprt, Rpl13a, Sdha and Tbp) and analysed all genes for stable expression in the mouse mammary gland from pre-puberty to adulthood using four different algorithms (GeNorm, DeltaCt, BestKeeper and NormFinder). Prdx1, Phf7 and Ctbp1 were validated as novel and reliable, tissue-specific reference genes that outperform traditional reference genes in qRT-PCR studies of postnatal mammary gland development. PMID:27752147

  3. Altered mammary gland development in male rats exposed to genistein and methoxychlor.

    PubMed

    Wang, Xiao-Juan; Bartolucci-Page, Erika; Fenton, Suzanne E; You, Li

    2006-05-01

    Genistein (GE) is a prevalent phytoestrogen whose presence in human and animal foods may affect biological actions of synthetic endocrine active compounds. We have previously reported that in utero and lactational exposure to high doses of GE or the endocrine active pesticide methoxychlor (MXC) caused mammary epithelial proliferation in 21-day-old male rats. Combined exposure to GE and MXC resulted in significant feminization of the male mammary glands. The goals of the current study were to evaluate mammary responses to GE and MXC at the adult stage and investigate relevant mechanisms. Following in utero, lactational exposure (through maternal diet), and direct dietary exposure, the inguinal mammary gland of male rats (90 days of age) was found to exhibit significant morphological alterations in the groups treated with GE and/or MXC compared to the control. GE exposure (at 300 and 800 ppm concentrations) caused lobular enlargement and epithelial proliferation, whereas MXC exposure (800 ppm) led to ductal elongation and lobular enlargement. Combining the two treatments caused prominent proliferation of both ducts and alveoli; secretory material was seen in readily recognizable alveolar lumens, which are absent in untreated male mammary. We also surveyed gene expression in the mammary tissue using a cDNA microarray and evaluated relevant protein factors. The results indicated that the treatment effects are likely due to interactions between steroid hormone receptor-mediated signals and growth factor-driven cellular pathways. The distinctive responses associated with the GE+MXC combination were likely linked to enhanced actions of insulin-like growth factor 1 and related downstream pathways.

  4. Development of a RNA extraction method from milk for gene expression study in the mammary gland of sheep.

    PubMed

    Mura, Maria Consuelo; Daga, Cinzia; Bodano, Sara; Paludo, Marta; Luridiana, Sebastiano; Pazzola, Michele; Dettori, Maria Luisa; Vacca, Giuseppe Massimo; Carcangiu, Vincenzo

    2013-03-01

    The aim of the study was to develop a reliable method for the RNA extraction from milk of Sarda sheep breed and to highlight if the extracted RNA can be used for expression study on mammary genes involved in milk fat synthesis using RT-qPCR. The main result is that a sample of 150 ml of milk provides an optimal amount of RNA (73.5 μg/ml). The highest RNA concentration has been found in the samples analysed within 4 h after collection. The RNA extracted was positively correlated to the number of somatic cells (P < 0.001). The efficiency of the extraction method was confirmed by the results obtained from qPCR which showed a Ct value, for SREBPF1 gene of 26.8 ± 0.15. This research demonstrated that the high-quality of the RNA obtained is suited to use for studies of mammary genes expression in sheep, avoiding any damage caused by mammary gland biopsy.

  5. Diet-induced obesity and mammary tumor development in MMTV-neu female mice.

    PubMed

    Cleary, Margot P; Grande, Joseph P; Juneja, Subhash C; Maihle, Nita J

    2004-01-01

    Obesity is a risk factor for postmenopausal breast cancer and is associated with shortened latency and/or increased mammary tumor (MT) incidence in animals. Elevated body weight is usually associated with hormone-responsive tumors. In agreement with these data we previously showed that latency of hormone-responsive MTs in MMTV-TGF-alpha mice with diet-induced obesity was significantly shortened. Here, we used the same protocol to determine the impact of diet-induced obesity on estrogen receptor-negative MT development in MMTV-neu (strain 202) mice. Mice were fed a low-fat diet (n=20) or a high-fat diet (n=54) from 10 wk of age. Body weight at 19 wk of age was used to assign high-fat mice to obesity-prone, overweight, and obesity-resistant groups. Mice were euthanized due to MT size or at 85 wk of age. Final body weights of obesity-prone mice were heaviest, and those of obesity-resistant and low-fat groups were similar. Fat pad weights were heaviest in obesity-prone mice followed by overweight and obesity-resistant groups, and lightest in low-fat mice. Serum IGF-I levels were similar for low-fat and high-fat mice, whereas leptin was higher in high-fat mice (P <0.0001). MT latency, incidence, metastasis, and burden were similar for all groups. These findings support that obesity is not a risk factor for development of estrogen-negative breast cancer.

  6. Dietary soy effects on mammary gland development during the pubertal transition in nonhuman primates

    PubMed Central

    Dewi, Fitriya N.; Wood, Charles E.; Lees, Cynthia J.; Willson, Cynthia J.; Register, Thomas C.; Tooze, Janet A.; Franke, Adrian A.; Cline, J. Mark

    2013-01-01

    While epidemiologic studies suggest that soy intake early in life may reduce breast cancer risk, there are also concerns that exposure to soy isoflavones during childhood may alter pubertal development and hormonal profiles. Here, we assessed the effect of a high-soy diet on pubertal breast development, sex hormones, and growth in a nonhuman primate model. Pubertal female cynomolgus monkeys were randomized to receive a diet modeled on a typical North American diet with one of two protein sources for ~4.5 years: i) casein/lactalbumin (CL, n=12, as control) or ii) soy protein isolate with a human equivalent dose of 120 mg/day isoflavones (SOY, n=17), which is comparable to approximately four servings of soy foods. Pubertal exposure to the SOY diet did not alter onset of menarche, indicators of growth and pubertal progression, or circulating estradiol and progesterone concentrations. Greater endometrial area was seen in the SOY group on the first of 4 postmenarchal ultrasound measurements (P<0.05). There was a subtle effect of diet on breast differentiation whereby the SOY group showed higher numbers of differentiated large-sized lobular units and a lower proportion with immature ducts following menarche (P<0.05). Numbers of small lobules and terminal end buds and mammary epithelial cell proliferation did not differ by diet. Expression of progesterone receptor was lower in immature lobules of soy-fed animals (P<0.05). Our findings suggest that consumption of soy starting before menarche may result in modest effects consistent with a more differentiated breast phenotype in adulthood. PMID:23771522

  7. In-Silico Genomic Approaches To Understanding Lactation, Mammary Development, And Breast Cancer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lactation-related traits are influenced by genetics. From a quantitative standpoint, these traits have been well studied in dairy species, but there has also been work on the genetics of lactation in humans and mice. In addition, there is evidence to support the notion that other mammary gland trait...

  8. A Compendium of the Mouse Mammary Tumor Biologist: From the Initial Observations in the House Mouse to the Development of Genetically Engineered Mice

    PubMed Central

    Cardiff, Robert D.; Kenney, Nicholas

    2011-01-01

    For over a century, mouse mammary tumor biology and the associated mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration in 1984. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skill sets to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this compendium is to extend an “olive branch” while simultaneously deepen the knowledge of the novice mouse mammary tumor biologist as they journey into a field rich in pathology and genetics spanning several centuries. PMID:20961975

  9. A compendium of the mouse mammary tumor biologist: from the initial observations in the house mouse to the development of genetically engineered mice.

    PubMed

    Cardiff, Robert D; Kenney, Nicholas

    2011-06-01

    For over a century, mouse mammary tumor biology and the associated mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration in 1984. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skill sets to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this compendium is to extend an "olive branch" while simultaneously deepen the knowledge of the novice mouse mammary tumor biologist as they journey into a field rich in pathology and genetics spanning several centuries. PMID:20961975

  10. A compendium of the mouse mammary tumor biologist: from the initial observations in the house mouse to the development of genetically engineered mice.

    PubMed

    Cardiff, Robert D; Kenney, Nicholas

    2011-06-01

    For over a century, mouse mammary tumor biology and the associated mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration in 1984. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skill sets to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this compendium is to extend an "olive branch" while simultaneously deepen the knowledge of the novice mouse mammary tumor biologist as they journey into a field rich in pathology and genetics spanning several centuries.

  11. Ductal barriers in mammary epithelium

    PubMed Central

    Owens, Mark B; Hill, Arnold DK; Hopkins, Ann M

    2013-01-01

    Tissue barriers play an integral role in the biology and pathobiology of mammary ductal epithelium. In normal breast physiology, tight and adherens junctions undergo dynamic changes in permeability in response to hormonal and other stimuli, while several of their proteins are directly involved in mammary tumorigenesis. This review describes first the structure of mammary ductal epithelial barriers and their role in normal mammary development, examining the cyclical changes in response to puberty, pregnancy, lactation and involution. It then examines the role of adherens and tight junctions and the participation of their constituent proteins in mammary tumorigenic functions such as migration, invasion and metastasis. Finally, it discusses the potential of these adhesion proteins as both prognostic biomarkers and potential therapeutic targets in breast cancer. PMID:24665412

  12. Differences in the Rate of in Situ Mammary Gland Development and Other Developmental Endpoints in Three Strains of Female Rat Commonly Used in Mammary Carcinogenesis Studies: Implications for Timing of Carcinogen Exposure.

    PubMed

    Stanko, Jason P; Kissling, Grace E; Chappell, Vesna A; Fenton, Suzanne E

    2016-10-01

    The potential of chemicals to alter susceptibility to mammary tumor formation is often assessed using a carcinogen-induced study design in various rat strains. The rate of mammary gland (MG) development must be considered so that the timing of carcinogen administration is impactful. In this study, in situ MG development was assessed in females of the Harlan Sprague-Dawley (Hsd:SD), Charles River Sprague-Dawley (Crl:SD), and Charles River Long-Evans (Crl:LE) rat strains at postnatal days 25, 33, and 45. Development was evaluated by physical assessment of growth parameters, developmental scoring, and quantitative morphometric analysis. Although body weight (BW) was consistently lower and day of vaginal opening (VO) occurred latest in female Hsd:SD rats, they exhibited accelerated pre- and peripubertal MG development compared to other strains. Glands of Crl:SD and Crl:LE rats exhibited significantly more terminal end buds (TEBs) and TEB/mm than Hsd:SD rats around the time of VO. These data suggest a considerable difference in the rate of MG development across commonly used strains, which is independent of BW and timing of VO. In mammary tumor induction studies employing these strains, administration of the carcinogen should be timed appropriately, based on strain, to specifically target the peak of TEB occurrence. PMID:27613105

  13. Genetic variants in mammary development, prolactin signalling and involution pathways explain considerable variation in bovine milk production and milk composition

    PubMed Central

    2014-01-01

    Background The maintenance of lactation in mammals is the result of a balance between competing signals from mammary development, prolactin signalling and involution pathways. Dairy cattle are an interesting case study to investigate the effect of polymorphisms that affect the function of genes in these pathways. In dairy cattle, lactation yields and milk composition (for example protein percentage and fat percentage) are routinely recorded, and these vary greatly between individuals. In this study, we test 8058 single nucleotide polymorphisms in or close to genes in these pathways for association with milk production traits and determine the proportion of variance explained by each pathway, using data on 16 812 dairy cattle, including Holstein-Friesian and Jersey bulls and cows. Results Single nucleotide polymorphisms close to genes in the mammary development, prolactin signalling and involution pathways were significantly associated with milk production traits. The involution pathway explained the largest proportion of genetic variation for production traits. The mammary development pathway also explained additional genetic variation for milk volume, fat percentage and protein percentage. Conclusions Genetic variants in the involution pathway explained considerably more genetic variation in milk production traits than expected by chance. Many of the associations for single nucleotide polymorphisms in genes in this pathway have not been detected in conventional genome-wide association studies. The pathway approach used here allowed us to identify some novel candidates for further studies that will be aimed at refining the location of associated genomic regions and identifying polymorphisms contributing to variation in lactation volume and milk composition. PMID:24779965

  14. Histone Demethylase Jumonji AT-rich Interactive Domain 1B (JARID1B) Controls Mammary Gland Development by Regulating Key Developmental and Lineage Specification Genes*

    PubMed Central

    Zou, Mike Ran; Cao, Jian; Liu, Zongzhi; Huh, Sung Jin; Polyak, Kornelia; Yan, Qin

    2014-01-01

    The JmjC domain-containing H3K4 histone demethylase jumonji AT-rich interactive domain 1B (JARID1B) (also known as KDM5B and PLU1) is overexpressed in breast cancer and is a potential target for breast cancer treatment. To investigate the in vivo function of JARID1B, we developed Jarid1b−/− mice and characterized their phenotypes in detail. Unlike previously reported Jarid1b−/− strains, the majority of these Jarid1b−/− mice were viable beyond embryonic and neonatal stages. This allowed us to further examine phenotypes associated with the loss of JARID1B in pubertal development and pregnancy. These Jarid1b−/− mice exhibited decreased body weight, premature mortality, decreased female fertility, and delayed mammary gland development. Related to these phenotypes, JARID1B loss decreased serum estrogen level and reduced mammary epithelial cell proliferation in early puberty. In mammary epithelial cells, JARID1B loss diminished the expression of key regulators for mammary morphogenesis and luminal lineage specification, including FOXA1 and estrogen receptor α. Mechanistically, JARID1B was required for GATA3 recruitment to the Foxa1 promoter to activate Foxa1 expression. These results indicate that JARID1B positively regulates mammary ductal development through both extrinsic and cell-autonomous mechanisms. PMID:24802759

  15. Over-expression of an endogenous milk protein gene in transgenic mice is associated with impaired mammary alveolar development and a milchlos phenotype.

    PubMed

    Burdon, T; Wall, R J; Shamay, A; Smith, G H; Hennighausen, L

    1991-12-01

    The whey acidic protein (WAP) gene is expressed in mammary epithelial cells at late pregnancy and throughout lactation. We have generated transgenic mice in which a mouse WAP transgene is expressed precociously in pregnancy. From 13 founder mice bearing WAP transgenes, two female founders and the daughters from a male founder failed to lactate and nurture their offspring. We named this phenotype milchlos. Mammary tissue from postpartum milchlos mice was underdeveloped, contained too few alveoli and resembled the glands of non-transgenic mid-pregnant mice. The hypothesis that alveolar development in milchlos mice was functionally arrested in a prelactational state is consistent with low levels of alpha-lactalbumin mRNA, and an unidentified keratin RNA in mammary tissue from postpartum mice. Defects in alveolar function in milchlos mice were detected at mid-pregnancy; in non-transgenic mice, WAP was secreted into the alveolar lumen but remained preferentially in the cytoplasm of the alveolar epithelial cells in the milchlos mice. Since deregulated WAP expression resulted in impaired mammary development, it is possible that WAP plays a regulatory role in the terminal differentiation and development of mammary alveolar cells. PMID:1782141

  16. Design and development of a dedicated mammary and axillary region positron emission tomography system

    NASA Astrophysics Data System (ADS)

    Doshi, Niraj Kumar

    Breast cancer is the second leading cause of cancer death in women. Currently, mammography and physical breast examination, both non-invasive techniques, provide the two most effective methods available for screening potential breast cancer patients. During the management of patients, however, several invasive techniques such as axillary lymph node dissection, core biopsies and lumpectomies, are utilized to determine the stage or malignancy of the disease with significant cost and morbidity associated with them. Positron Emission Tomography (PET), using [F-18] fluorodeoxyglucose (FDG) tracer is a sensitive and non-invasive imaging modality that may be a cost-effective alternative to certain invasive procedures. In this project we have developed a low cost, high performance, dedicated PET camera (maxPET) for mammary and axillary region imaging. The system consists of two 15x15 cm2 planar scintillation detector arrays composed of modular detectors operating in coincidence. The modular detectors are comprised of a 9x9 array of 3x3x20 mm3 lutetiurn oxyorthosilicate (LSO) detector elements, read out by a 5x5 array of position- sensitive photomultiplier tubes. The average measured intrinsic spatial resolution of a detector module is 2.26 mm with a sensitivity of up to 40% for a central point source. The measured coincidence timing resolution for two modules is 2.4 ns. The average energy resolution measured across the entire two detector plates is 21.6%. The coincidence timing resolution for the entire system is 8.1 ns. A line bar phantom was imaged and images were reconstructed using the focal plane tomography algorithm. A 4 mm projection image resolution was measured based on profiles taken through the line bar phantom images. The goal of the maxPET system will be to aid in breast cancer patient management by assisting in imaging women with dense, fibro-glandular breasts, detecting axillary lymph node metastases without surgery, monitoring chemotherapy effectiveness and

  17. Improved development of somatic cell cloned bovine embryos by a mammary gland epithelia cells in vitro model

    PubMed Central

    Ma, Li-bing; He, Xiao-ning; Si, Wan-tong; Zheng, Yue-Mao

    2016-01-01

    Previous studies have established a bovine mammary gland epithelia cells in vitro model by the adenovirus-mediated telomerase (hTERT-bMGEs). The present study was conducted to confirm whether hTERT-bMGEs were effective target cells to improve the efficiency of transgenic expression and somatic cell nuclear transfer (SCNT). To accomplish this, a mammary-specific vector encoding human lysozyme and green fluorescent protein was used to verify the transgenic efficiency of hTERT-bMGEs, and untreated bovine mammary gland epithelial cells (bMGEs) were used as a control group. The results showed that the hTERT-bMGEs group had much higher transgenic efficiency and protein expression than the bMGEs group. Furthermore, the nontransgenic and transgenic hTERT-bMGEs were used as donor cells to evaluate the efficiency of SCNT. There were no significant differences in rates of cleavage or blastocysts or hatched blastocysts of cloned embryos from nontransgenic hTERT-bMGEs at passage 18 and 28 groups (82.8% vs. 81.9%, 28.6% vs. 24.8%, 58.6% vs. 55.3%, respectively) and the transgenic group (80.8%, 26.5% and 53.4%); however, they were significantly higher than the bMGEs group (71.2%, 12.8% and 14.8%), (p < 0.05). We confirmed that hTERT-bMGEs could serve as effective target cells for improving development of somatic cell cloned cattle embryos. PMID:26243608

  18. Improved development of somatic cell cloned bovine embryos by a mammary gland epithelia cells in vitro model.

    PubMed

    He, Xiao-Ying; Ma, Li-Bing; He, Xiao-Ning; Si, Wan-Tong; Zheng, Yue-Mao

    2016-06-30

    Previous studies have established a bovine mammary gland epithelia cells in vitro model by the adenovirus-mediated telomerase (hTERT-bMGEs). The present study was conducted to confirm whether hTERT-bMGEs were effective target cells to improve the efficiency of transgenic expression and somatic cell nuclear transfer (SCNT). To accomplish this, a mammary-specific vector encoding human lysozyme and green fluorescent protein was used to verify the transgenic efficiency of hTERT-bMGEs, and untreated bovine mammary gland epithelial cells (bMGEs) were used as a control group. The results showed that the hTERT-bMGEs group had much higher transgenic efficiency and protein expression than the bMGEs group. Furthermore, the nontransgenic and transgenic hTERT-bMGEs were used as donor cells to evaluate the efficiency of SCNT. There were no significant differences in rates of cleavage or blastocysts or hatched blastocysts of cloned embryos from nontransgenic hTERT-bMGEs at passage 18 and 28 groups (82.8% vs. 81.9%, 28.6% vs. 24.8%, 58.6% vs. 55.3%, respectively) and the transgenic group (80.8%, 26.5% and 53.4%); however, they were significantly higher than the bMGEs group (71.2%, 12.8% and 14.8%), (p < 0.05). We confirmed that hTERT-bMGEs could serve as effective target cells for improving development of somatic cell cloned cattle embryos. PMID:26243608

  19. Improved development of somatic cell cloned bovine embryos by a mammary gland epithelia cells in vitro model.

    PubMed

    He, Xiao-Ying; Ma, Li-Bing; He, Xiao-Ning; Si, Wan-Tong; Zheng, Yue-Mao

    2016-06-30

    Previous studies have established a bovine mammary gland epithelia cells in vitro model by the adenovirus-mediated telomerase (hTERT-bMGEs). The present study was conducted to confirm whether hTERT-bMGEs were effective target cells to improve the efficiency of transgenic expression and somatic cell nuclear transfer (SCNT). To accomplish this, a mammary-specific vector encoding human lysozyme and green fluorescent protein was used to verify the transgenic efficiency of hTERT-bMGEs, and untreated bovine mammary gland epithelial cells (bMGEs) were used as a control group. The results showed that the hTERT-bMGEs group had much higher transgenic efficiency and protein expression than the bMGEs group. Furthermore, the nontransgenic and transgenic hTERT-bMGEs were used as donor cells to evaluate the efficiency of SCNT. There were no significant differences in rates of cleavage or blastocysts or hatched blastocysts of cloned embryos from nontransgenic hTERT-bMGEs at passage 18 and 28 groups (82.8% vs. 81.9%, 28.6% vs. 24.8%, 58.6% vs. 55.3%, respectively) and the transgenic group (80.8%, 26.5% and 53.4%); however, they were significantly higher than the bMGEs group (71.2%, 12.8% and 14.8%), (p < 0.05). We confirmed that hTERT-bMGEs could serve as effective target cells for improving development of somatic cell cloned cattle embryos.

  20. Effect of conjoint administration of tamoxifen and high-dose radiation on the development of mammary carcinoma

    SciTech Connect

    Kantorowitz, D.A. ); Thompson, H.J. ); Furmanski, P. )

    1993-04-30

    Tamoxifen is currently advocated for post-menopausal breast cancer patients receiving definitive irradiation after limited surgery. The purpose of this study was to assess in an experimental model for breast cancer whether the efficacy of irradiation is altered by conjoint administration of tamoxifen. To this end, rats with small tumors induced by 1-methyl-1-nitrosourea (MNU) were treated with tamoxifen, radiation, or a combination of the two modalities. Female Sprague Dawley rats were injected i.p. with 50 mg MNU/kg body weight at 50 days of age. At 64 days post carcinogen, the majority of the rats had at least one palpable mammary tumor. At that time radiation with or without tamoxifen treatment was initiated and given 5 days per week for 5 weeks. Radiation dose was 4500 cGy delivered as 25, 180 cGy fractions. Tamoxifen, 500 mg/kg body weight, was administered subcutaneously each day during the irradiation interval. The study was terminated 28 weeks after carcinogen treatment. High dose radiation alone induced a reduction in the size of existing tumors, but resulted in a significant increase in the number of tumors that were detected. Treatment with tamoxifen alone also caused a reduction in tumor volume, but had no effect on final incidence or number of mammary tumors. Combined modality treatment resulted in a significant reduction in the volume of existing tumors and suppressed the enhanced occurrence of additional tumors observed when only radiation alone was administered. The findings of this study indicate that in the context of fractionated, high dose radiation treatment of established mammary cancers, tamoxifen may reduce the likelihood of subsequent tumor development and by so doing prove a helpful simultaneous conjoint adjuvant treatment to post-operative irradiation. 35 refs., 1 fig., 2 tabs.

  1. Immunobiology of the mammary gland.

    PubMed

    Sordillo, L M; Shafer-Weaver, K; DeRosa, D

    1997-08-01

    The mammary gland is a complex organ that provides neonatal offspring with milk for nourishment and disease resistance. Specific and innate immune factors associated with mammary gland tissues and secretion also play a vital role in protecting the gland from infectious disease. Through genetic selection and technological advances in milk removal, the bovine mammary gland yields for more milk than is needed to nourish the newborn calf. This excess is the basis of the dairy industry. Factors associated with the intense management of dairy cattle can profoundly affect mammary gland immunity and the ability of the host to resist mastitis. Technological advances in immunology have led to the availability of new research tools that can facilitate the study of mammary gland immunity and disease pathogenesis. In recent years, considerable research effort has focused on enhancing the natural defense mechanisms of the mammary gland during periods of heightened susceptibility to disease. This paper provides a comprehensive overview of mammary gland immunity with special emphasis on the bovine system. The underlying mechanisms of disease susceptibility and development of potential immunoregulatory strategies to control mastitis are discussed.

  2. Dose-rate effects of mammary tumor development in female Sprague-Dawley rats exposed to X and gamma radiation

    SciTech Connect

    Johnson, J.R.; Gragtmans, N.J.; Myers, D.K.; Jones, A.R.

    1989-06-01

    Mammary tumour development was followed in two experiments involving a total of 2229 female Sprague-Dawley rats exposed to various doses of X or gamma rays at different dose rates. The data for another 462 rats exposed to tritiated water in one of these experiments were also analyzed. The incidence of adenocarcinomas and fibroadenomas at a given time after exposure increased linearly in proportion to total radiation dose for most groups. However, no significant increase in adenocarcinomas was observed with chronic gamma exposures up to 1.1 Gy, and the increase in fibroadenomas observed with chronic gamma exposures at a dose rate of 0.0076 Gy h-1 up to an accumulated dose of 3.3 Gy was small compared to that observed after acute exposures. The incidence of all mammary tumors increased almost linearly with the log of dose rate in the range 0.0076 to 26.3 Gy h-1 for 3 Gy total dose of gamma rays. The effects of X rays appeared to be less influenced by dose rate than were the effects of gamma rays.

  3. Development of new therapy for canine mammary cancer with recombinant measles virus

    PubMed Central

    Shoji, Koichiro; Yoneda, Misako; Fujiyuki, Tomoko; Amagai, Yosuke; Tanaka, Akane; Matsuda, Akira; Ogihara, Kikumi; Naya, Yuko; Ikeda, Fusako; Matsuda, Hiroshi; Sato, Hiroki; Kai, Chieko

    2016-01-01

    Oncolytic virotherapy is a promising treatment strategy for cancer. We previously generated a recombinant measles virus (rMV-SLAMblind) that selectively uses a poliovirus receptor-related 4 (PVRL4/Nectin4) receptor, but not signaling lymphocyte activation molecule (SLAM). We demonstrated that the virus exerts therapeutic effects against human breast cancer cells. Here, we examined the applicability of rMV-SLAMblind to treating canine mammary cancers (CMCs). We found that the susceptibilities of host cells to rMV-SLAMblind were dependent on canine Nectin-4 expression. Nectin-4 was detected in four of nine CMC cell lines. The rMV-SLAMblind efficiently infected those four Nectin-4-positive cell lines and was cytotoxic for three of them (CF33, CHMm, and CTBm). In vivo experiment showed that the administration of rMV-SLAMblind greatly suppressed the progression of tumors in mice xenografted with a CMC cell line (CF33). Immunohistochemistry revealed that canine Nectin-4 was expressed in 45% of canine mammary tumors, and the tumor cells derived from one clinical specimen were efficiently infected with rMV-SLAMblind. These results suggest that rMV-SLAMblind infects CMC cells and displays antitumor activity in vitro, in xenografts, and ex vivo. Therefore, oncolytic virotherapy with rMV-SLAMblind can be a novel method for treating CMCs. PMID:27119113

  4. Loss of EZH2 results in precocious mammary gland development and activation of STAT5-dependent genes

    PubMed Central

    Yoo, Kyung Hyun; Oh, Sumin; Kang, Keunsoo; Hensel, Tim; Robinson, Gertraud W.; Hennighausen, Lothar

    2015-01-01

    Establishment and differentiation of mammary alveoli during pregnancy are controlled by prolactin through the transcription factors STAT5A and STAT5B (STAT5), which also regulate temporal activation of mammary signature genes. This study addressed the question whether the methyltransferase and transcriptional co-activator EZH2 controls the differentiation clock of mammary epithelium. Ablation of Ezh2 from mammary stem cells resulted in precocious differentiation of alveolar epithelium during pregnancy and the activation of mammary-specific STAT5 target genes. This coincided with enhanced occupancy of these loci by STAT5, EZH1 and RNA Pol II. Limited activation of differentiation-specific genes was observed in mammary epithelium lacking both EZH2 and STAT5, suggesting a modulating but not mandatory role for STAT5. Loss of EZH2 did not result in overt changes in genome-wide and gene-specific H3K27me3 profiles, suggesting compensation through enhanced EZH1 recruitment. Differentiated mammary epithelia did not form in the combined absence of EZH1 and EZH2. Transplantation experiments failed to demonstrate a role for EZH2 in the activity of mammary stem and progenitor cells. In summary, while EZH1 and EZH2 serve redundant functions in the establishment of H3K27me3 marks and the formation of mammary alveoli, the presence of EZH2 is required to control progressive differentiation of milk secreting epithelium during pregnancy. PMID:26250110

  5. Sustained trophism of the mammary gland is sufficient to accelerate and synchronize development of ErbB2/Neu-induced tumors

    PubMed Central

    Landis, MD; Seachrist, DD; Abdul-Karim, FW; Keri, RA

    2006-01-01

    Epidemiological studies indicate that parity enhances HER2/ErbB2/Neu-induced breast tumorigenesis. Furthermore, recent studies using multiparous, ErbB2/Neu-overexpressing mouse mammary tumor virus (MMTV-Neu) mice have shown that parity induces a population of cells that are targeted for ErbB2/Neu-induced transformation. Although parity accelerates mammary tumorigenesis, the pattern of tumor development in multiparous MMTV-Neu mice remains stochastic, suggesting that additional events are required for ErbB2/Neu to cause mammary tumors. Whether such events are genetic in nature or reflective of the dynamic hormonal control of the gland that occurs with pregnancy remains unclear. We postulated that young age at pregnancy initiation or chronic trophic maintenance of mammary epithelial cells might provide a cellular environment that significantly increases susceptibility to ErbB2/Neu-induced tumorigenesis. MMTV-Neu mice that were maintained pregnant or lactating beginning at 3 weeks of age demonstrated accelerated tumorigenesis, but this process was still stochastic, indicating that early pregnancy does not provide the requisite events of tumorigenesis. However, bitransgenic mice that were generated by breeding MMTV-Neu mice with a luteinizing hormone-overexpressing mouse model of ovarian hyperstimulation developed multifocal mammary tumors in an accelerated, synchronous manner compared to virgin MMTV-Neu animals. This synchrony of tumor development in the bitransgenic mice suggests that trophic maintenance of the mammary gland provides the additional events required for tumor formation and maintains the population of cells that are targeted by ErbB2/Neu for transformation. Both the synchrony of tumor appearance and the ability to characterize a window of commitment by ovariectomy/palpation studies permitted microarray analysis to evaluate changes in gene expression over a defined timeline that spans the progression from normal to preneoplastic mammary tissue. These

  6. Application of Sholl Analysis to Quantify Changes in Growth and Development in Rat Mammary Gland Whole Mounts

    PubMed Central

    Stanko, Jason P.; Easterling, Michael R.; Fenton, Suzanne E.

    2014-01-01

    Studies that utilize the rodent mammary gland (MG) as an endpoint for assessing the developmental toxicity of chemical exposures typically employ either basic dimensional measurements or developmental scoring of morphological characteristics as a means to quantify MG development. There are numerous means by which to report these developmental changes, leading to inconsistent translation across laboratories. The Sholl analysis is a method historically used for quantifying neuronal dendritic patterns. The present study describes the use of the Sholl analysis to quantify MG branching characteristics. Using this method, we were able to detect significant differences in branching density in MG of peripubertal female Sprague Dawley rats that had been exposed to vehicle or a potent estrogen. These data suggest the Sholl analysis can be an effective tool for quantitatively measuring an important characteristic of MG development and for examining associations between MG growth and density and adverse effects in the breast. PMID:25463529

  7. Connexins, E-cadherin, Claudin-7 and β-catenin transiently form junctional nexuses during the post-natal mammary gland development.

    PubMed

    Dianati, Elham; Poiraud, Jérémy; Weber-Ouellette, Anne; Plante, Isabelle

    2016-08-01

    Gap junctions are intercellular channels made of connexins (Cxs) that allow direct communication between adjacent cells. Modulation of Cxs has been associated with abnormal development and function of the mammary gland and breast cancer. However, the mechanisms underlying their expression during normal mammary gland are not yet known. Cxs interact with components of tight and adherens junctions. Thus, we hypothesized that the expression levels of Cxs vary during mammary gland development and are regulated through stage-dependent interactions with members of the tight and adherens junctions. Our specific objectives were to: 1) determine the expression of Cxs and tight and adherens junction proteins throughout development and 2) characterize Cxs interactions with components of tight and adherens junctions. Murine mammary glands were sampled at various developmental stages (pre-pubescent to post-weaning). RT-qPCR and western-blot analyses demonstrated differential expression patterns for all gap (Cx43, Cx32, Cx26, Cx30), tight (Claudin-1, -3, -4, -7) and adherens (β-catenin, E- and P-cadherins) junctions throughout development. Interestingly, co-immunoprecipitation demonstrated interactions between these different types of junctions. Cx30 interacted with Cx26 just at the late pregnancy stage. While Cx43 showed a persistent interaction with β-catenin from virginity to post-weaning, its interactions with E-cadherin and Claudin-7 were transient. Cx32 interacted with Cx26, E-cadherin and β-catenin during lactation. Immunofluorescence results confirmed the existence of a junctional nexus that remodeled during mammary gland development. Together, our results confirm that the expression levels of Cxs vary concomitantly and that Cxs form junctional nexuses with tight and adherens junctions, suggesting the existence of common regulatory pathways.

  8. Vitamin D and the mammary gland: a review on its role in normal development and breast cancer.

    PubMed

    Lopes, Nair; Paredes, Joana; Costa, José Luis; Ylstra, Bauke; Schmitt, Fernando

    2012-05-31

    Breast cancer is a heterogeneous disease associated with diverse biological behaviours and clinical outcome. Although some molecular subgroups of breast cancer have a targeted therapy, the most aggressive tumours still lack a molecular target. Despite vitamin D being classically associated with the physiological role of calcium regulation and phosphate transport in bone metabolism, several studies have demonstrated a wide range of functions for this hormone, which are particularly important in the field of cancer. The mechanisms underlying the protective actions of vitamin D in cancer development are only sparsely understood, but evidence shows that vitamin D participates in cell growth regulation, apoptosis and cell differentiation. In addition, it has been implicated in the suppression of cancer cell invasion, angiogenesis and metastasis. Most of vitamin D biological actions are mediated by the vitamin D receptor and the synthesis and catabolism of this hormone are regulated by the enzymes CYP27B1 and CYP24A1. In the present review we highlight research data concerning the function of this hormone in the mammary gland, with a special focus on breast carcinogenesis. Hence, and although the available data are controversial, we consider not only updated information on the epidemiology of vitamin D in breast cancer and its potential value as a therapeutic agent or prophylactic (with an emphasis on molecular mechanisms and effectors of vitamin D action), but include data on its role in other stages of breast cancer progression as well. Accordingly, we review data on the influence of vitamin D in the development of normal breast and the expression of vitamin D-related proteins (VDR, CYP27B1 and CYP24A21) in benign mammary lesions and ductal carcinomas in situ.

  9. Modulation of mammary gland development in pre-pubertal mice as affected by soya and milk protein supplements.

    PubMed

    Alston-Mills, Brenda; Lepri, J J; Martin, C A

    2011-08-01

    The objective of the present study was to determine the effects of soya and whey milk protein, α-lactalbumin (α-LA), on mammary gland morphology and the structural support of the gland, in pre-pubertal mice after 7 d of treatment. In Expt 1, weaned (day 21) CD1 mice were given one of the four treatments, three included dietary supplements: (1) control diet, casein, (2) soya, (3) α-LA and (4) subcutaneous injection of 2·5 μg oestradiol benzoate in 20 μl maize oil and fed the control diet. All diets were isoenergetic with equal protein concentrations. All groups that were not treated with oestradiol received the vehicle. Whole-mount analyses were performed to determine longitudinal ductal growth and terminal end bud development. DNA was extracted from the gland and assessed by spectrophotometry (260/280 nm). Tissue extracts for extracellular matrix (ECM) proteins, matrix metalloproteinase-2 (MMP(2)), tissue inhibitor of MMP(2) (TIMP(2)), and serum oestradiol and mammary tissue epidermal growth factors (EGF) were measured by immunoassays. Expt 2 utilised the Her2/neu transgenic strain, with the same protocols. Statistical significance was determined by one-way ANOVA. From Expt 1 and 2, soya and α-LA significantly increased ductal elongation when compared with the oestrogen and control groups. These results were corroborated by data on total DNA and the ratio of MMP(2):TIMP(2). The ratio of MMP(2):TIMP(2) was affected by α-LA. Serum oestradiol was decreased only in the oestradiol-treated groups in both experiments. Soya is known to be oestrogenic and can act on epithelia directly. The mechanism by which α-LA affects glandular development is by modulating the ECM or by promoting the synthesis/activity of EGF.

  10. The use of alternative polyadenylation sites renders integrin β1 (Itgb1) mRNA isoforms with differential stability during mammary gland development.

    PubMed

    Naipauer, Julian; Gattelli, Albana; Degese, Maria Sol; Slomiansky, Victoria; Wertheimer, Eva; LaMarre, Jonathan; Castilla, Lucio; Abba, Martin; Kordon, Edith C; Coso, Omar A

    2013-09-01

    Integrins are heterodimeric cell-surface adhesion receptors that play a critical role in tissue development. Characterization of the full-length mRNA encoding the β1 subunit (Itgb1) revealed an alternative functional cleavage and polyadenylation site that yields a new Itgb1 mRNA isoform 578 bp shorter than that previously reported. Using a variety of experimental and bioinformatic approaches, we found that the two Itgb1 isoforms are expressed at different levels in a variety of mouse tissues, including the mammary gland, where they are differentially regulated at successive developmental stages. The longer mRNA species is prevelant during lactation, whereas the shorter is induced after weaning. In 3D cultures, where expression of integrin β1 protein is required for normal formation of acini, experimental blockade of the longer isoform induced enhanced expression of the shorter species which allowed normal morphological mammary differentiation. The short isoform lacks AU-rich motifs and miRNA target sequences that are potentially implicated in the regulation of mRNA stability and translation efficiency. We further determined that the AU-binding protein HuR appears to selectively stabilize the longer isoform in the mammary gland. In summary, the results of the present study identify a new regulatory instance involved in the fine-tuning of Itgb1 expression during mammary gland development and function.

  11. Differentiation dynamics of mammary epithelial stem cells from Korean holstein dairy cattle under ECM-free conditions.

    PubMed

    Sharma, Neelesh; Kim, Jeong Hyun; Sodhi, Simrinder Singh; Luong, Do Huynh; Kim, Sung-Woo; Oh, Sung Jong; Jeong, Dong Kee

    2015-01-01

    The "stem cells" are commonly defined as "cells capable of self-renewal through replication and differentiating into specific lineages". The mammary gland contains functional stem/progenitor cells. The current study was planned with the objectives to study the differentiation dynamics of Korean Holstein mammary epithelial stem cells (KHMESCs) under the optimum culture conditions. Lineage negative KHMESCs isolated from mammary tissue of lactating cows have shown the typical differentiation dynamics with formation of lobulo-alveolar structures in in vitro culture. This suggests the existence of bipotential mammary epithelial stem cells in the mammary gland. The strong mRNA expression of pluripotency factors indicates stemness, whereas expression of milk protein genes and epithelial cell-specific gene indicate their differentiation capabilities. Further, immunostaining results have shown the differentiation capabilities of KHMESCs into both luminal and basal lineages under the extracellular matrix (ECM, matrigel) free environment. However, under matrigel, the differentiation process was comparatively higher than without matrigel. Immunostaining results also suggested that differentiated cells could secrete milk proteins such as β-casein. To our knowledge, these data represent the first report on the differentiation dynamics and establishment of mammary epithelial stem cells from Korean Holstein with typical stemness properties. It was observed that isolated KHMESCs had normal morphology, growth pattern, differentiation ability, cytogenetic and secretory activity even without ECM. Therefore, it is concluded that established KHMESCs could be used for further studies on Korean Holstein dairy cows related to lactation studies, as non-GMO animal bioreactors and stem cell-based management of bovine mastitis including post-mastitis damage.

  12. A new role of SNAI2 in postlactational involution of the mammary gland links it to luminal breast cancer development

    DOE PAGES

    Castillo-Lluva, Sonia; Hontecillas-Prieto, Lourdes; Blanco-Gómez, Adrian; del Mar Sáez-Freire, María; García-Cenador, Begona; García-Criado, Javier; Pérez-Andrés, Martín; Orfao, Alberto; Cañamero, Marta; Mao, Jian-Hua; et al

    2015-06-22

    Breast cancer is a major cause of mortality in women. The transcription factor SNAI2 has been implicated in the pathogenesis of several types of cancer, including breast cancer of basal origin. Here we show that SNAI2 is also important in the development of breast cancer of luminal origin in MMTV-ErbB2 mice. SNAI2 deficiency leads to longer latency and fewer luminal tumors, both of these being characteristics of pretumoral origin. These effects were associated with reduced proliferation and a decreased ability to generate mammospheres in normal mammary glands. However, the capacity to metastasize was not modified. Under conditions of increased ERBB2more » oncogenic activity after pregnancy plus SNAI2 deficiency, both pretumoral defects-latency and tumor load-were compensated. However, the incidence of lung metastases was dramatically reduced. Furthermore, SNAI2 was required for proper postlactational involution of the breast. At 3 days post lactational involution, the mammary glands of Snai2-deficient mice exhibited lower levels of pSTAT3 and higher levels of pAKT1, resulting in decreased apoptosis. Abundant noninvoluted ducts were still present at 30 days post lactation, with a greater number of residual ERBB2+ cells. These results suggest that this defect in involution leads to an increase in the number of susceptible target cells for transformation, to the recovery of the capacity to generate mammospheres and to an increase in the number of tumors. In conclusion, our work demonstrates the participation of SNAI2 in the pathogenesis of luminal breast cancer, and reveals an unexpected connection between the processes of postlactational involution and breast tumorigenesis in Snai2-null mutant mice.« less

  13. A new role of SNAI2 in postlactational involution of the mammary gland links it to luminal breast cancer development

    SciTech Connect

    Castillo-Lluva, Sonia; Hontecillas-Prieto, Lourdes; Blanco-Gómez, Adrian; del Mar Sáez-Freire, María; García-Cenador, Begona; García-Criado, Javier; Pérez-Andrés, Martín; Orfao, Alberto; Cañamero, Marta; Mao, Jian-Hua; Gridley, Thomas; Castellanos-Martín, Andres; Pérez-Losada, Jesus

    2015-06-22

    Breast cancer is a major cause of mortality in women. The transcription factor SNAI2 has been implicated in the pathogenesis of several types of cancer, including breast cancer of basal origin. Here we show that SNAI2 is also important in the development of breast cancer of luminal origin in MMTV-ErbB2 mice. SNAI2 deficiency leads to longer latency and fewer luminal tumors, both of these being characteristics of pretumoral origin. These effects were associated with reduced proliferation and a decreased ability to generate mammospheres in normal mammary glands. However, the capacity to metastasize was not modified. Under conditions of increased ERBB2 oncogenic activity after pregnancy plus SNAI2 deficiency, both pretumoral defects-latency and tumor load-were compensated. However, the incidence of lung metastases was dramatically reduced. Furthermore, SNAI2 was required for proper postlactational involution of the breast. At 3 days post lactational involution, the mammary glands of Snai2-deficient mice exhibited lower levels of pSTAT3 and higher levels of pAKT1, resulting in decreased apoptosis. Abundant noninvoluted ducts were still present at 30 days post lactation, with a greater number of residual ERBB2+ cells. These results suggest that this defect in involution leads to an increase in the number of susceptible target cells for transformation, to the recovery of the capacity to generate mammospheres and to an increase in the number of tumors. In conclusion, our work demonstrates the participation of SNAI2 in the pathogenesis of luminal breast cancer, and reveals an unexpected connection between the processes of postlactational involution and breast tumorigenesis in Snai2-null mutant mice.

  14. Evo-devo of the mammary gland.

    PubMed

    Oftedal, Olav T; Dhouailly, Danielle

    2013-06-01

    We propose a new scenario for mammary evolution based on comparative review of early mammary development among mammals. Mammary development proceeds through homologous phases across taxa, but evolutionary modifications in early development produce different final morphologies. In monotremes, the mammary placode spreads out to form a plate-like mammary bulb from which more than 100 primary sprouts descend into mesenchyme. At their distal ends, secondary sprouts develop, including pilosebaceous anlagen, resulting in a mature structure in which mammary lobules and sebaceous glands empty into the infundibula of hair follicles; these structural triads (mammolobular-pilo-sebaceous units or MPSUs) represent an ancestral condition. In marsupials a flask-like mammary bulb elongates as a sprout, but then hollows out; its secondary sprouts include hair and sebaceous anlagen (MPSUs), but the hairs are shed during nipple formation. In some eutherians (cat, horse, human) MPSUs form at the distal ends of primary sprouts; pilosebaceous components either regress or develop into mature structures. We propose that a preexisting structural triad (the apocrine-pilo-sebaceous unit) was incorporated into the evolving mammary structure, and coupled to additional developmental processes that form the mammary line, placode, bulb and primary sprout. In this scenario only mammary ductal trees and secretory tissue derive from ancestral apocrine-like glands. The mammary gland appears to have coopted signaling pathways and genes for secretory products from even earlier integumentary structures, such as odontode (tooth-like) or odontode-derived structures. We speculate that modifications in signal use (such as PTHrP and BMP4) may contribute to taxonomic differences in MPSU development. PMID:23681303

  15. WFDC2 is differentially expressed in the mammary gland of the tammar wallaby and provides immune protection to the mammary gland and the developing pouch young.

    PubMed

    Watt, Ashalyn P; Sharp, Julie A; Lefevre, Christophe; Nicholas, Kevin R

    2012-03-01

    WAP four disulfide core domain 2 (WFDC2) is a four disulfide core (4-DSC) protein secreted in the milk of the tammar wallaby. It is comprised of two 4-DSC domains assigned domain III at the NH2-terminal end and domain II at the COOH-terminal end. The WFDC2 gene was expressed only during pregnancy, early lactation, towards the end of lactation and involution. The WFDC2 protein showed antibacterial activity against Staphylococcus aureus, Salmonella enterica and Pseudomonas aeruginosa and this activity resided with domain II. There was no antibacterial activity detected against Enterococcus faecalis. The observed expression pattern of tammar WFDC2 and its antibacterial activity suggests a role to either reduce mastitis in the mammary gland caused by S. aureus or to protect the gut of the young at a time when it is not immune-competent. The latter effect could be achieved without disturbing the balance of commensal gut flora such as E. faecalis. PMID:22024352

  16. Mammary hypertrophy in an ovariohysterectomized cat.

    PubMed

    Pukay, B P; Stevenson, D A

    1983-05-01

    A four year old ovariohysterectomized domestic short-haired cat under treatment for behavioral urine spraying and idiopathic alopecia developed mammary gland hypertrophy following treatment with megestrol acetate. Withdrawal of the progestin and treatment with androgen failed to cause regression of the hypertrophy. The affected mammary gland was surgically excised and recovery was uneventful.

  17. ‘The charmingest place’: non-coding RNA, lineage tracing, tumor heterogeneity, metastasis and metabolism - new methods in mammary gland development and cancer: the fifth ENBDC Workshop

    PubMed Central

    2013-01-01

    The European Network for Breast Development and Cancer (ENBDC) Workshop on ‘Methods in Mammary Gland Development and Cancer’ has grown into the essential, international technical discussion forum for scientists with interests in the normal and neoplastic breast. The fifth ENBDC meeting was held in Weggis, Switzerland in April, 2013, and focussed on emerging, state-of-the-art techniques for the study of non-coding RNA, lineage tracing, tumor heterogeneity, metastasis and metabolism. PMID:24103450

  18. Does cancer start in the womb? altered mammary gland development and predisposition to breast cancer due to in utero exposure to endocrine disruptors.

    PubMed

    Soto, Ana M; Brisken, Cathrin; Schaeberle, Cheryl; Sonnenschein, Carlos

    2013-06-01

    We are now witnessing a resurgence of theories of development and carcinogenesis in which the environment is again being accepted as a major player in phenotype determination. Perturbations in the fetal environment predispose an individual to disease that only becomes apparent in adulthood. For example, gestational exposure to diethylstilbestrol resulted in clear cell carcinoma of the vagina and breast cancer. In this review the effects of the endocrine disruptor bisphenol-A (BPA) on mammary development and tumorigenesis in rodents is used as a paradigmatic example of how altered prenatal mammary development may lead to breast cancer in humans who are also widely exposed to it through plastic goods, food and drink packaging, and thermal paper receipts. Changes in the stroma and its extracellular matrix led to altered ductal morphogenesis. Additionally, gestational and lactational exposure to BPA increased the sensitivity of rats and mice to mammotropic hormones during puberty and beyond, thus suggesting a plausible explanation for the increased incidence of breast cancer.

  19. The Mammary Glands of Macaques

    PubMed Central

    Cline, J. Mark; Wood, Charles E.

    2009-01-01

    This review describes the normal biology and physiology of the mammary gland in macaques, including the typical histologic appearance across the life span (development, reproductive maturity, lactation, and senescence). The molecular events regulating breast morphogenesis are described, as well as systemic and local hormonal regulators of mammary gland proliferation, differentiation, and function. Similarities and differences to the human breast are described. Regulatory events are illuminated by discussion of genetically modified mouse models. Tissue response markers, including immunohistochemical markers of proliferation and other hormonally induced changes and studies to date, regarding the effects of exogenous hormones, are briefly summarized. In general, estrogens stimulate progesterone receptor expression and proliferation in the mammary gland, and combinations of estrogens and progestogens cause greater proliferation than estrogens alone. Evaluation of novel chemical agents in macaques requires careful evaluation of age and hormonal context to avoid the confounding effects of mammary gland development, past reproductive history, and other influences on mammary gland morphology. The expression of proliferation markers and progesterone receptors may be used as biomarkers to measure chemically induced hormonal effects. PMID:21475638

  20. A prognosis classifier for breast cancer based on conserved gene regulation between mammary gland development and tumorigenesis: a multiscale statistical model.

    PubMed

    Tian, Yingpu; Chen, Baozhen; Guan, Pengfei; Kang, Yujia; Lu, Zhongxian

    2013-01-01

    Identification of novel cancer genes for molecular therapy and diagnosis is a current focus of breast cancer research. Although a few small gene sets were identified as prognosis classifiers, more powerful models are still needed for the definition of effective gene sets for the diagnosis and treatment guidance in breast cancer. In the present study, we have developed a novel statistical approach for systematic analysis of intrinsic correlations of gene expression between development and tumorigenesis in mammary gland. Based on this analysis, we constructed a predictive model for prognosis in breast cancer that may be useful for therapy decisions. We first defined developmentally associated genes from a mouse mammary gland epithelial gene expression database. Then, we found that the cancer modulated genes were enriched in this developmentally associated genes list. Furthermore, the developmentally associated genes had a specific expression profile, which associated with the molecular characteristics and histological grade of the tumor. These result suggested that the processes of mammary gland development and tumorigenesis share gene regulatory mechanisms. Then, the list of regulatory genes both on the developmental and tumorigenesis process was defined an 835-member prognosis classifier, which showed an exciting ability to predict clinical outcome of three groups of breast cancer patients (the predictive accuracy 64∼72%) with a robust prognosis prediction (hazard ratio 3.3∼3.8, higher than that of other clinical risk factors (around 2.0-2.8)). In conclusion, our results identified the conserved molecular mechanisms between mammary gland development and neoplasia, and provided a unique potential model for mining unknown cancer genes and predicting the clinical status of breast tumors. These findings also suggested that developmental roles of genes may be important criteria for selecting genes for prognosis prediction in breast cancer. PMID:23565194

  1. A prognosis classifier for breast cancer based on conserved gene regulation between mammary gland development and tumorigenesis: a multiscale statistical model.

    PubMed

    Tian, Yingpu; Chen, Baozhen; Guan, Pengfei; Kang, Yujia; Lu, Zhongxian

    2013-01-01

    Identification of novel cancer genes for molecular therapy and diagnosis is a current focus of breast cancer research. Although a few small gene sets were identified as prognosis classifiers, more powerful models are still needed for the definition of effective gene sets for the diagnosis and treatment guidance in breast cancer. In the present study, we have developed a novel statistical approach for systematic analysis of intrinsic correlations of gene expression between development and tumorigenesis in mammary gland. Based on this analysis, we constructed a predictive model for prognosis in breast cancer that may be useful for therapy decisions. We first defined developmentally associated genes from a mouse mammary gland epithelial gene expression database. Then, we found that the cancer modulated genes were enriched in this developmentally associated genes list. Furthermore, the developmentally associated genes had a specific expression profile, which associated with the molecular characteristics and histological grade of the tumor. These result suggested that the processes of mammary gland development and tumorigenesis share gene regulatory mechanisms. Then, the list of regulatory genes both on the developmental and tumorigenesis process was defined an 835-member prognosis classifier, which showed an exciting ability to predict clinical outcome of three groups of breast cancer patients (the predictive accuracy 64∼72%) with a robust prognosis prediction (hazard ratio 3.3∼3.8, higher than that of other clinical risk factors (around 2.0-2.8)). In conclusion, our results identified the conserved molecular mechanisms between mammary gland development and neoplasia, and provided a unique potential model for mining unknown cancer genes and predicting the clinical status of breast tumors. These findings also suggested that developmental roles of genes may be important criteria for selecting genes for prognosis prediction in breast cancer.

  2. Apigenin prevents development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats

    PubMed Central

    Mafuvadze, Benford; Benakanakere, Indira; Lopez, Franklin; Besch-Williford, Cynthia; Ellersieck, Mark R.; Hyder, Salman M.

    2011-01-01

    The use of progestins as a component of hormone replacement therapy has been linked to an increase in breast cancer risk in postmenopausal women. We have previously shown that medroxyprogesterone acetate (MPA), a commonly administered synthetic progestin, increases production of the potent angiogenic factor vascular endothelial growth factor (VEGF) by tumor cells, leading to the development of new blood vessels and tumor growth. We sought to identify nontoxic chemicals that would inhibit progestin-induced tumorigenesis. We used a recently developed progestin-dependent mammary cancer model in which tumors are induced in Sprague-Dawley rats by 7,12-dimethylbenz(a)anthracene (DMBA) treatment. The flavonoid apigenin, which we previously found to inhibit progestin-dependent VEGF synthesis in human breast cancer cells in vitro, significantly delayed the development of, and decreased the incidence and multiplicity of, MPA-accelerated DMBA-induced mammary tumors in this animal model. Whereas apigenin decreased the occurrence of such tumors, it did not block MPA-induced intraductal and lobular epithelial cell hyperplasia in the mammary tissue. Apigenin blocked MPA-dependent increases in VEGF, and suppressed VEGF receptor-2 (VEGFR-2) but not VEGFR-1 in regions of hyperplasia. No differences were observed in estrogen or progesterone receptor levels, or the number of estrogen receptor-positive cells, within the mammary gland of MPA-treated animals administered apigenin, MPA-treated animals, and placebo treated animals. However, the number of progesterone receptor-positive cells was reduced in animals treated with MPA or MPA and apigenin compared with those treated with placebo. These findings suggest that apigenin has important chemopreventive properties for those breast cancers that develop in response to progestins. PMID:21505181

  3. Pleiotrophin (PTN) expression and function and in the mouse mammary gland and mammary epithelial cells.

    PubMed

    Rosenfield, Sonia M; Bowden, Emma T; Cohen-Missner, Shani; Gibby, Krissa A; Ory, Virginie; Henke, Ralf T; Riegel, Anna T; Wellstein, Anton

    2012-01-01

    Expression of the heparin-binding growth factor, pleiotrophin (PTN) in the mammary gland has been reported but its function during mammary gland development is not known. We examined the expression of PTN and its receptor ALK (Anaplastic Lymphoma Kinase) at various stages of mouse mammary gland development and found that their expression in epithelial cells is regulated in parallel during pregnancy. A 30-fold downregulation of PTN mRNA expression was observed during mid-pregnancy when the mammary gland undergoes lobular-alveolar differentiation. After weaning of pups, PTN expression was restored although baseline expression of PTN was reduced significantly in mammary glands of mice that had undergone multiple pregnancies. We found PTN expressed in epithelial cells of the mammary gland and thus used a monoclonal anti-PTN blocking antibody to elucidate its function in cultured mammary epithelial cells (MECs) as well as during gland development. Real-time impedance monitoring of MECs growth, migration and invasion during anti-PTN blocking antibody treatment showed that MECs motility and invasion but not proliferation depend on the activity of endogenous PTN. Increased number of mammospheres with laminin deposition after anti-PTN blocking antibody treatment of MECs in 3D culture and expression of progenitor markers suggest that the endogenously expressed PTN inhibits the expansion and differentiation of epithelial progenitor cells by disrupting cell-matrix adhesion. In vivo, PTN activity was found to inhibit ductal outgrowth and branching via the inhibition of phospho ERK1/2 signaling in the mammary epithelial cells. We conclude that PTN delays the maturation of the mammary gland by maintaining mammary epithelial cells in a progenitor phenotype and by inhibiting their differentiation during mammary gland development.

  4. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review.

    PubMed

    Lohakare, J D; Südekum, K-H; Pattanaik, A K

    2012-09-01

    This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only reduces the age of sexual maturity but also lowers the time period of attaining the age of first calving. However, high energy diets may cause undesirable fat deposition thereby affecting future milk yield potential. Discrepancies exist whether overfed or overweight heifers at puberty can influence the mammary development and future milk yield potential and performance. The data on post-pubertal nutritional management suggested that body weight at calving and post-pubertal growth rate is important in first lactation milk yield. There is a continuous research need for strategic feeding that accelerates growth of dairy heifers without reduction in subsequent production. Nutritional management from birth, across puberty and during pregnancy is critical for mammary growth and for producing a successful cow. This review will mostly highlight studies carried out on dairy breeds and possible available opportunities to manipulate nutritional status from birth until age at first calving.

  5. Effects of selenium and low levels of lead on mammary tumor development and growth in MMTV-infected female mice.

    PubMed

    Schrauzer, G N

    2008-12-01

    Selenium (Se) has been demonstrated in previous studies to inhibit mammary tumorigenesis in C3H mice infected with the murine mammary tumorvirus, MMTV. The antitumorigenic effects of Se in this animal model of breast cancer were subsequently shown to be counteracted by Se-antagonistic elements. Lead (Pb), for example, was found to abolish the anticarcinogenic effects of Se at 5 ppm in the drinking water. The present study was undertaken to explore the effects of Pb at just 0.5 ppm in the water, i.e., at a level comparable to the concentrations of Pb that have been measured in the tap water of older homes in some communities. Groups of 30 female virgin C3H/St mice infected with MMTV maintained on Torula yeast-based diets containing either 0.15 or 0.65 ppm of yeast-based organic Se and received either deionized water or water containing 0.5 ppm Pb as the acetate over their entire postweaning lifespan. In the control group on deionized water and the 0.15 ppm Se feed, the tumor incidence was 78.6%, which is normal for this strain. Increasing the Se content of the feed to 0.65 ppm lowered the tumor incidence to 30%, demonstrating the antitumorigenic effect of Se. In the experimental groups, the Pb-exposed mice on the 0.15 ppm Se feed developed signs of chronic Pb toxicity as evidenced by diminished weight gain that persisted up to the age of 10 months, during which period the animals remained tumor-free. Thereafter, weight gains ensued to near the values of the controls, and the tumors began to develop in rapid succession until the final tumor incidence of 73.7% was reached. In the group of mice on the 0.65 ppm Se feed, the toxic effects of Pb were diminished, as evidenced by the normal weight gains during the first 10 months but with concomitant physiological inactivation of Se, causing 82.6% of the mice to develop tumors, with the first tumor to appear at the age of 5 months, 7 months earlier than in the Pb-unexposed controls. In addition, tumor growth rates in this

  6. Estimation of mammary gland composition using CdTe series detector developed for photon-counting mammography

    NASA Astrophysics Data System (ADS)

    Ihori, Akiko; Okamoto, Chizuru; Yamakawa, Tsutomu; Yamamoto, Shuichiro; Okada, Masahiro; Nakajima, Ai; Kato, Misa; Kodera, Yoshie

    2016-03-01

    Energy resolved photon-counting mammography is a new technology, which counts the number of photons that passes through an object, and presents it as a pixel value in an image of the object. Silicon semiconductor detectors are currently used in commercial mammography. However, the disadvantage of silicon is the low absorption efficiency for high X-ray energies. A cadmium telluride (CdTe) series detector has a high absorption efficiency over a wide energy range. In this study, we proposed a method to estimate the composition of the mammary gland using a CdTe series detector as a photon-counting detector. The fact that the detection rate of breast cancer in mammography is affected by mammary gland composition is now widely accepted. Assessment of composition of the mammary gland has important implications. An important advantage of our proposed technique is its ability to discriminate photons using three energy bins. We designed the CdTe series detector system using the MATLAB simulation software. The phantom contains nine regions with the ratio of glandular tissue and adipose varying in increments of 10%. The attenuation coefficient for each bin's energy was calculated from the number of input and output photons possessed by each. The evaluation results obtained by plotting the attenuation coefficient μ in a three-dimensional (3D) scatter plot show that the plots had a regular composition order congruent with that of the mammary gland. Consequently, we believe that our proposed method can be used to estimate the composition of the mammary gland.

  7. YB-1 transforms human mammary epithelial cells through chromatin remodeling leading to the development of basal-like breast cancer

    PubMed Central

    Davies, Alastair H.; Reipas, Kristen M.; Pambid, Mary Rose; Berns, Rachel; Stratford, Anna L.; Fotovati, Abbas; Firmino, Natalie; Astanehe, Arezoo; Hu, Kaiji; Maxwell, Christopher; Mills, Gordon B.; Dunn, Sandra E.

    2015-01-01

    There is growing evidence that cancer-initiation could result from epigenetic changes. Y-box binding protein-1 (YB-1) is a transcription/translation factor that promotes the formation of tumors in transgenic mice; however, the underlying molecular events are not understood. To explore this in a human model system, YB-1 was expressed in mammary epithelial cells under the control of a tetracycline-inducible promoter. The induction of YB-1 promoted phenotypes associated with malignancy in three-dimensional breast acini cultures. This was attributed to YB-1 enhancing the expression and activity of the histone acetyltransferase p300 leading to chromatin remodeling. Specifically, this relaxation of chromatin allowed YB-1 to bind to the BMI1 promoter. The induction of BMI1 engaged the Polycomb complex resulting in histone H2A ubiquitylation and repression of the CDKN2A locus. These events manifested functionally as enhanced self-renewal capacity that occurred in a BMI1-dependent manner. Conversely, p300 inhibition with anacardic acid prevented YB-1 from binding to the BMI1 promoter and thereby subverted self-renewal. Despite these early changes, full malignant transformation was not achieved until RSK2 became overexpressed concomitant with elevated hTERT activity. The YB-1/RSK2/hTERT expressing cells formed tumors in mice that were molecularly subtyped as basal-like breast cancer. We conclude that YB-1 cooperates with p300 to allow BMI1 to over-ride p16INK4a-mediated cell cycle arrest enabling self-renewal and the development of aggressive breast tumors. PMID:24648416

  8. Mouse mammary tumor biology: a short history.

    PubMed

    Cardiff, Robert D; Kenney, Nicholas

    2007-01-01

    For over a century, mouse mammary tumor biology and the associated Mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology, and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration, in 1984, that the mouse mammary gland could be molecularly targeted and used to test the oncogenicity of candidate human genes. Now, very few scientists can avoid using a mouse model to test the biology of their favorite gene. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skills to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this short history of mouse mammary tumor biology is to provide a historical perspective for the benefit of the newcomers. If Einstein was correct in that "we stand on the shoulders of giants," the neophytes should meet their giants.

  9. Mammary gland: From embryogenesis to adult life.

    PubMed

    Musumeci, Giuseppe; Castrogiovanni, Paola; Szychlinska, Marta Anna; Aiello, Flavia Concetta; Vecchio, Giada Maria; Salvatorelli, Lucia; Magro, Gaetano; Imbesi, Rosa

    2015-01-01

    The aim of this review is to focus on the molecular factors that ensure the optimal development and maintenance of the mammary gland thanks to their integration and coordination. The development of the mammary gland is supported, not only by endocrine signals, but also by regulatory molecules, which are able to integrate signals from the surrounding microenvironment. A major role is certainly played by homeotic genes, but their incorrect expression during the spatiotemporal regulation of proliferative, functional and differentiation cycles of the mammary gland, may result in the onset of neoplastic processes. Attention is directed also to the endocrine aspects and sexual dimorphism of mammary gland development, as well as the role played by ovarian steroids and their receptors in adult life.

  10. The consequence of level of nutrition on heifer ovarian and mammary development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Replacing cows in the herd is second only to nutrition as the single greatest input cost in cow/calf beef production. The increased availability of cereal grains for feeding livestock has allowed replacement heifers to enter the production system at younger ages. Many heifer development programs fe...

  11. The mammary cellular hierarchy and breast cancer.

    PubMed

    Oakes, Samantha R; Gallego-Ortega, David; Ormandy, Christopher J

    2014-11-01

    Advances in the study of hematopoietic cell maturation have paved the way to a deeper understanding the stem and progenitor cellular hierarchy in the mammary gland. The mammary epithelium, unlike the hematopoietic cellular hierarchy, sits in a complex niche where communication between epithelial cells and signals from the systemic hormonal milieu, as well as from extra-cellular matrix, influence cell fate decisions and contribute to tissue homeostasis. We review the discovery, definition and regulation of the mammary cellular hierarchy and we describe the development of the concepts that have guided our investigations. We outline recent advances in in vivo lineage tracing that is now challenging many of our assumptions regarding the behavior of mammary stem cells, and we show how understanding these cellular lineages has altered our view of breast cancer.

  12. Two distinct phases of apoptosis in mammary gland involution: proteinase-independent and -dependent pathways

    SciTech Connect

    Lund, Leif R; Romer, John; Thomasset, Nicole; Solberg, Helene; Pyke, Charles; Bissell, Mina J; Dano, Keld; Werb, Zena

    1996-01-01

    Postlactational involution of the mammary gland is characterized by two distinct physiological events: apoptosis of the secretory, epithelial cells undergoing programmed cell death, and proteolytic degradation of the mammary gland basement membrane. We examined the spatial and temporal patterns of apoptotic cells in relation to those of proteinases during involution of the BALB/c mouse mammary gland. Apoptosis was almost absent during lactation but became evident at day 2 of involution, when {beta}-casein gene expression was still high. Apoptotic cells were then seen at least up to day 8 of involution, when {beta}-casein gene expression was being extinguished. Expression of sulfated glycoprotein-2 (SGP-2), interleukin-1{beta} converting enzyme (ICE) and tissue inhibitor of metalloproteinases-1 was upregulated at day 2, when apoptotic cells were seen initially. Expression of the matrix metalloproteinases gelatinase A and stromelysin-1 and the serine proteinase urokinase-type plasminogen activator, which was low during lactation, was strongly upregulated in parallel starting at day 4 after weaning, coinciding with start of the collapse of the lobulo-alveolar structures and the intensive tissue remodeling in involution. The major sites of mRNA synthesis for these proteinases were fibroblast-like cells in the periductal stroma and stromal cells surrounding the collapsed alveoli, suggesting that the degradative phase of involution is due to a specialized mesenchymal-epithelial interaction. To elucidate the functional role of these proteinases during involution, at the onset of weaning we treated mice systemically with the glucocorticoid hydrocortisone, which is known to inhibit mammary gland involution. Although the initial wave of apoptotic cells appeared in the lumina of the gland, the dramatic regression and tissue remodeling usually evident by day 5 was substantially inhibited by systemic treatment with hydrocortisone. mRNA and protein for gelatinase A, stromelysin

  13. Abnormal peripubertal development of the rat mammary gland following exposure in utero and during lactation to a mixture of genistein and the food contaminant vinclozolin.

    PubMed

    El Sheikh Saad, H; Meduri, G; Phrakonkham, P; Bergès, R; Vacher, S; Djallali, M; Auger, J; Canivenc-Lavier, M C; Perrot-Applanat, M

    2011-07-01

    The impact of early exposure to endocrine disruptor mixtures on mammary gland development is poorly known. Here, we identify the effects of a conception to weaning exposure of rats to the phytoestrogen genistein (G) and/or the antiandrogen vinclozolin (V) at 1mg/kg-d, alone or in association. Using several approaches, we found that G- and GV-exposed rats displayed significantly greater epithelial branching and proliferation, wider terminal end buds than controls at PND35, as well as ductal hyperplasia and periductal fibrosis. Focal branching defects were present in V-exposed rats. An increased ER and AR expression was observed in G- and GV- as compared to V-exposed rats at PND35. Surprisingly, a significant number of GV- and to a lesser extent, V-exposed animals displayed abnormal hyperplasic alveolar structures at PND50. Thus, gestational and lactational exposure to low doses of genistein plus vinclozolin may seriously affect peripubertal development of the rat mammary gland.

  14. Identification of Putative Ortholog Gene Blocks Involved in Gestant and Lactating Mammary Gland Development: A Rodent Cross-Species Microarray Transcriptomics Approach

    PubMed Central

    Rodríguez-Cruz, Maricela; Coral-Vázquez, Ramón M.; Hernández-Stengele, Gabriel; Sánchez, Raúl; Salazar, Emmanuel; Sanchez-Muñoz, Fausto; Encarnación-Guevara, Sergio; Ramírez-Salcedo, Jorge

    2013-01-01

    The mammary gland (MG) undergoes functional and metabolic changes during the transition from pregnancy to lactation, possibly by regulation of conserved genes. The objective was to elucidate orthologous genes, chromosome clusters and putative conserved transcriptional modules during MG development. We analyzed expression of 22,000 transcripts using murine microarrays and RNA samples of MG from virgin, pregnant, and lactating rats by cross-species hybridization. We identified 521 transcripts differentially expressed; upregulated in early (78%) and midpregnancy (89%) and early lactation (64%), but downregulated in mid-lactation (61%). Putative orthologous genes were identified. We mapped the altered genes to orthologous chromosomal locations in human and mouse. Eighteen sets of conserved genes associated with key cellular functions were revealed and conserved transcription factor binding site search entailed possible coregulation among all eight block sets of genes. This study demonstrates that the use of heterologous array hybridization for screening of orthologous gene expression from rat revealed sets of conserved genes arranged in chromosomal order implicated in signaling pathways and functional ontology. Results demonstrate the utilization power of comparative genomics and prove the feasibility of using rodent microarrays to identification of putative coexpressed orthologous genes involved in the control of human mammary gland development. PMID:24288657

  15. PTEN Loss in E-Cadherin-Deficient Mouse Mammary Epithelial Cells Rescues Apoptosis and Results in Development of Classical Invasive Lobular Carcinoma.

    PubMed

    Boelens, Mirjam C; Nethe, Micha; Klarenbeek, Sjoerd; de Ruiter, Julian R; Schut, Eva; Bonzanni, Nicola; Zeeman, Amber L; Wientjens, Ellen; van der Burg, Eline; Wessels, Lodewyk; van Amerongen, Renée; Jonkers, Jos

    2016-08-23

    Invasive lobular carcinoma (ILC) is an aggressive breast cancer subtype with poor response to chemotherapy. Besides loss of E-cadherin, a hallmark of ILC, genetic inactivation of PTEN is frequently observed in patients. Through concomitant Cre-mediated inactivation of E-cadherin and PTEN in mammary epithelium, we generated a mouse model of classical ILC (CLC), the main histological ILC subtype. While loss of E-cadherin induced cell dissemination and apoptosis, additional PTEN inactivation promoted cell survival and rapid formation of invasive mammary tumors that recapitulate the histological and molecular features, estrogen receptor (ER) status, growth kinetics, metastatic behavior, and tumor microenvironment of human CLC. Combined inactivation of E-cadherin and PTEN is sufficient to cause CLC development. These CLCs showed significant tumor regression upon BEZ235-mediated inhibition of PI3K signaling. In summary, this mouse model provides important insights into CLC development and suggests inhibition of phosphatidylinositol 3-kinase (PI3K) signaling as a potential therapeutic strategy for targeting CLC. PMID:27524621

  16. The Cleared Mammary Fat Pad Transplantation Assay for Mammary Epithelial Organogenesis.

    PubMed

    Lawson, Devon A; Werb, Zena; Zong, Yang; Goldstein, Andrew S

    2015-12-01

    Cleared mammary fat pad (MFP) transplantation has been a standard technique for studies of mammary development and cancer for several decades. The mammary gland is comprised of several fundamental components: The epithelial compartment contains basal/myoepithelial cells and luminal cells, and the stromal compartment (called the MFP) contains adipocytes, smooth muscle cells, fibroblasts, and immune cells. In 3- to 4-wk-old female mice, the mammary epithelium is concentrated very close to the nipple and has not yet grown beyond the mammary lymph node to penetrate the bulk of the MFP. This developmental feature provides an anatomical fixed point, and enables one to cut away the portion of the MFP from the nipple to the lymph node, leaving behind the majority of the MFP free of epithelium. The "cleared" MFP can serve as a supportive native microenvironment fully sufficient for the organogenesis of injected donor epithelium. Normal mammary epithelial donor cells will produce histologically and functionally normal mammary ductal epithelium several weeks posttransplant, with the exception that the ducts will not be connected to the nipple. The assay described here provides a powerful platform for assessing the developmental and tumorigenic potential of engineered cells of interest. PMID:26631119

  17. The Cleared Mammary Fat Pad Transplantation Assay for Mammary Epithelial Organogenesis.

    PubMed

    Lawson, Devon A; Werb, Zena; Zong, Yang; Goldstein, Andrew S

    2015-12-02

    Cleared mammary fat pad (MFP) transplantation has been a standard technique for studies of mammary development and cancer for several decades. The mammary gland is comprised of several fundamental components: The epithelial compartment contains basal/myoepithelial cells and luminal cells, and the stromal compartment (called the MFP) contains adipocytes, smooth muscle cells, fibroblasts, and immune cells. In 3- to 4-wk-old female mice, the mammary epithelium is concentrated very close to the nipple and has not yet grown beyond the mammary lymph node to penetrate the bulk of the MFP. This developmental feature provides an anatomical fixed point, and enables one to cut away the portion of the MFP from the nipple to the lymph node, leaving behind the majority of the MFP free of epithelium. The "cleared" MFP can serve as a supportive native microenvironment fully sufficient for the organogenesis of injected donor epithelium. Normal mammary epithelial donor cells will produce histologically and functionally normal mammary ductal epithelium several weeks posttransplant, with the exception that the ducts will not be connected to the nipple. The assay described here provides a powerful platform for assessing the developmental and tumorigenic potential of engineered cells of interest.

  18. Epigenetic regulation of LSD1 during mammary carcinogenesis

    PubMed Central

    Wu, Yadi; Zhou, Binhua P

    2014-01-01

    Inheritable epigenetic regulation is integral to the dynamic control of gene expression under different stimuli for cellular homeostasis and disease progression. Histone methylation is a common and important type of chromatin modification. LSD1, the first known histone lysine-specific demethylase, operates as a key component of several corepressor complexes during development and in disease states. In this review, we focus on the regulation of LSD1 in mammary carcinogenesis. LSD1 plays a role in promoting mammary tumor metastasis and proliferation and in maintaining mammary cancer stem cells. Therefore, LSD1 represents a viable therapeutic target for effective treatment of mammary carcinogenesis. PMID:27308339

  19. Comparison of the transcriptpmes of long-tern label retaining-cells and C cells microdissected from mammary epithelium: an initial study to character potential stem/progenitor cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mammary stem cells (MaSC) account for the cell lineage of mammary epithelia and provide for mammary growth, development and tissue homeostasis. The presence of MaSC was clearly demonstrated by the generation of an entire mammary gland from a single cell implanted into epithelium-ablated mammary fat...

  20. ROLES OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF-A) IN MEDIATION OF DIOXIN (TCDD)-INDUCED DELAYS IN DEVELOPMENT OF THE MOUSE MAMMARY GLAND

    EPA Science Inventory

    Roles of Epidermal Growth Factor (EGF) and Transforming Growth Factor-alpha (TGF-a) in Mediation of Dioxin (TCDD)-Induced Delays in Development of the Mouse Mammary Gland.
    Suzanne E. Fenton, Barbara Abbott, Lamont Bryant, and Angela Buckalew. U.S. EPA, NHEERL, Reproductive Tox...

  1. Stem cells in normal mammary gland and breast cancer.

    PubMed

    Luo, Jie; Yin, Xin; Ma, Tao; Lu, Jun

    2010-04-01

    The mammary gland is a structurally dynamic organ that undergoes dramatic alterations with age, menstrual cycle, and reproductive status. Mammary gland stem cells, the minor cell population within the mature organ, are thought to have multiple functions in regulating mammary gland development, tissue maintenance, major growth, and structural remodeling. In addition, accumulative evidence suggests that breast cancers are initiated and maintained by a subpopulation of tumor cells with stem cell features (called cancer stem cells). A variety of methods have been developed to identify and characterize mammary stem cells, and several signal transduction pathways have been identified to be essential for the self-renewal and differentiation of mammary gland stem cells. Understanding the origin of breast cancer stem cells, their relationship to breast cancer development, and the differences between normal and cancer stem cells may lead to novel approaches to breast cancer diagnosis, prevention, and treatment.

  2. Molecular evolution of a novel marsupial S100 protein (S100A19) which is expressed at specific stages of mammary gland and gut development.

    PubMed

    Kwek, Joly H L; Wynne, Alicia; Lefèvre, Christophe; Familari, Mary; Nicholas, Kevin R; Sharp, Julie A

    2013-10-01

    a role in gut development, which differs between metatherians and eutherians, and/or include a potential antibacterial role in order to establish the correct flora and protect against spiral bacteria in the immature forestomach. In the mammary gland it may protect the tissue from infection at times of vulnerability during the lactation cycle.

  3. Genistein-mediated inhibition of mammary stromal adipocyte differentiation limits expansion of mammary stem/progenitor cells by paracrine signaling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mammary adiposity may contribute to breast cancer development and progression by releasing cytokines and other inflammatory mediators that promote mammary epithelial proliferation. We evaluated the effects of soy isoflavone genistein (GEN) on the adipogenic differentiation of a SV40-immortalized mou...

  4. Roles of Fas and Fas ligand during mammary gland remodeling

    PubMed Central

    Song, Joon; Sapi, Eva; Brown, Wendi; Nilsen, Jon; Tartaro, Karrie; Kacinski, Barry M.; Craft, Joseph; Naftolin, Frederick; Mor, Gil

    2000-01-01

    Mammary involution is associated with degeneration of the alveolar structure and programmed cell death of mammary epithelial cells. In this study, we evaluated the expression of Fas and Fas ligand (FasL) in the mammary gland tissue and their possible role in the induction of apoptosis of mammary cells. FasL-positive cells were observed in normal mammary epithelium from pregnant and lactating mice, but not in nonpregnant/virgin mouse mammary tissue. Fas expression was observed in epithelial and stromal cells in nonpregnant mice but was absent during pregnancy. At day 1 after weaning, high levels of both Fas and FasL proteins and caspase 3 were observed and coincided with the appearance of apoptotic cells in ducts and glands. During the same period, no apoptotic cells were found in the Fas-deficient (MRL/lpr) and FasL-deficient (C3H/gld) mice. Increase in Fas and FasL protein was demonstrated in human (MCF10A) and mouse (HC-11) mammary epithelial cells after incubation in hormone-deprived media, before apoptosis was detected. These results suggest that the Fas-FasL interaction plays an important role in the normal remodeling of mammary tissue. Furthermore, this autocrine induction of apoptosis may prevent accumulation of cells with mutations and subsequent neoplastic development. Failure of the Fas/FasL signal could contribute to tumor development. PMID:11086022

  5. An autoregulatory enhancer controls mammary-specific STAT5 functions

    PubMed Central

    Metser, Gil; Shin, Ha Youn; Wang, Chaochen; Yoo, Kyung Hyun; Oh, Sumin; Villarino, Alejandro V.; O'Shea, John J.; Kang, Keunsoo; Hennighausen, Lothar

    2016-01-01

    Signal Transducers and Activators of Transcription (STATs) are principal transcription factors downstream of cytokine receptors. Although STAT5A is expressed in most tissues it remains to be understood why its premier, non-redundant functions are restricted to prolactin-induced mammary gland development and function. We report that the ubiquitously expressed Stat5a/b locus is subject to additional lineage-specific transcriptional control in mammary epithelium. Genome-wide surveys of epigenetic status and transcription factor occupancy uncovered a putative mammary-specific enhancer within the intergenic sequences separating the two Stat5 genes. This region exhibited several hallmarks of genomic enhancers, including DNaseI hypersensitivity, H3K27 acetylation and binding by GR, NFIB, ELF5 and MED1. Mammary-specific STAT5 binding was obtained at two canonical STAT5 binding motifs. CRISPR/Cas9-mediated genome editing was used to delete these sites in mice and determine their biological function. Mutant animals exhibited an 80% reduction of Stat5 levels in mammary epithelium and a concomitant reduction of STAT5-dependent gene expression. Transcriptome analysis identified a class of mammary-restricted genes that was particularly dependent on high STAT5 levels as a result of the intergenic enhancer. Taken together, the mammary-specific enhancer enables a positive feedback circuit that contributes to the remarkable abundance of STAT5 and, in turn, to the efficacy of STAT5-dependent mammary physiology. PMID:26446995

  6. An autoregulatory enhancer controls mammary-specific STAT5 functions.

    PubMed

    Metser, Gil; Shin, Ha Youn; Wang, Chaochen; Yoo, Kyung Hyun; Oh, Sumin; Villarino, Alejandro V; O'Shea, John J; Kang, Keunsoo; Hennighausen, Lothar

    2016-02-18

    Signal Transducers and Activators of Transcription (STATs) are principal transcription factors downstream of cytokine receptors. Although STAT5A is expressed in most tissues it remains to be understood why its premier, non-redundant functions are restricted to prolactin-induced mammary gland development and function. We report that the ubiquitously expressed Stat5a/b locus is subject to additional lineage-specific transcriptional control in mammary epithelium. Genome-wide surveys of epigenetic status and transcription factor occupancy uncovered a putative mammary-specific enhancer within the intergenic sequences separating the two Stat5 genes. This region exhibited several hallmarks of genomic enhancers, including DNaseI hypersensitivity, H3K27 acetylation and binding by GR, NFIB, ELF5 and MED1. Mammary-specific STAT5 binding was obtained at two canonical STAT5 binding motifs. CRISPR/Cas9-mediated genome editing was used to delete these sites in mice and determine their biological function. Mutant animals exhibited an 80% reduction of Stat5 levels in mammary epithelium and a concomitant reduction of STAT5-dependent gene expression. Transcriptome analysis identified a class of mammary-restricted genes that was particularly dependent on high STAT5 levels as a result of the intergenic enhancer. Taken together, the mammary-specific enhancer enables a positive feedback circuit that contributes to the remarkable abundance of STAT5 and, in turn, to the efficacy of STAT5-dependent mammary physiology.

  7. P-cadherin expression in feline mammary tissues.

    PubMed

    Figueira, Ana Catarina; Teodósio, Ana Sofia; Carvalheira, Júlio; Lacerda, Manuela; de Matos, Augusto; Gärtner, Fátima

    2012-01-01

    The search for molecular markers in the feline mammary gland, namely, the adhesion molecules belonging to the cadherin family, is useful in the understanding of the development of mammary carcinomas in felines and humans. To study P-cadherin expression in the feline mammary gland, 61 samples of normal (n = 4), hyperplastic (n = 12), and neoplastic (n = 45) feline mammary tissues were examined. In both normal and hyperplastic mammary tissues as well as in benign tumours, P-cadherin immunolabelling was restricted to myoepithelial cells. In malignant tumours, however, there was an aberrant epithelial P-cadherin immunoexpression in 64.1% (n = 25) of cases, with a membranous and/or cytoplasmic pattern of distribution. A statistically significant relationship was seen between epithelial P-cadherin expression and malignant mammary lesions (P = 0.0001). In malignant mammary tumours, there was likewise a statistically significant relationship between aberrant P-cadherin immunoexpression and histological grade (P = 0.0132). Aberrant epithelial P-cadherin expression seems to be related to malignancy in the feline mammary gland. To confirm the results of this investigation, further studies with larger samples and follow-up studies are warranted.

  8. Of Microenvironments and Mammary Stem Cells

    SciTech Connect

    LaBarge, Mark A; Petersen, Ole W; Bissell, Mina J

    2007-06-01

    In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion and directs their critical functions. Thus guided, stem cells are able to maintain tissue homeostasis throughout the ebb and flow of metabolic and physical demands encountered over a lifetime. Indeed, a pool of stem cells maintains mammary gland structure throughout development, and responds to the physiological demands associated with pregnancy. This review discusses how stem cells were identified in both human and mouse mammary glands; each requiring different techniques that were determined by differing biological needs and ethical constraints. These studies together create a robust portrait of mammary gland biology and identify the location of the stem cell niche, elucidate a developmental hierarchy, and suggest how the niche might be manipulated for therapeutic benefit.

  9. Fibronectin Expression Modulates Mammary Epithelial Cell Proliferation during Acinar Differentiation

    PubMed Central

    Williams, Courtney M.; Engler, Adam J.; Slone, R. Daniel; Galante, Leontine L.; Schwarzbauer, Jean E.

    2009-01-01

    The mammary gland consists of a polarized epithelium surrounded by a basement membrane matrix that forms a series of branching ducts ending in hollow, sphere-like acini. Essential roles for the epithelial basement membrane during acinar differentiation, in particular laminin and its integrin receptors, have been identified using mammary epithelial cells cultured on a reconstituted basement membrane. Contributions from fibronectin, which is abundant in the mammary gland during development and tumorigenesis, have not been fully examined. Here, we show that fibronectin expression by mammary epithelial cells is dynamically regulated during the morphogenic process. Experiments with synthetic polyacrylamide gel substrates implicate both specific extracellular matrix components, including fibronectin itself, and matrix rigidity in this regulation. Alterations in fibronectin levels perturbed acinar organization. During acinar development, increased fibronectin levels resulted in overproliferation of mammary epithelial cells and increased acinar size. Addition of fibronectin to differentiated acini stimulated proliferation and reversed growth arrest of mammary epithelial cells negatively affecting maintenance of proper acinar morphology. These results show that expression of fibronectin creates a permissive environment for cell growth that antagonizes the differentiation signals from the basement membrane. These effects suggest a link between fibronectin expression and epithelial cell growth during development and oncogenesis in the mammary gland. PMID:18451144

  10. STAT signaling in mammary gland differentiation, cell survival and tumorigenesis.

    PubMed

    Haricharan, S; Li, Y

    2014-01-25

    The mammary gland is a unique organ that undergoes extensive and profound changes during puberty, menstruation, pregnancy, lactation and involution. The changes that take place during puberty involve large-scale proliferation and invasion of the fat-pad. During pregnancy and lactation, the mammary cells are exposed to signaling pathways that inhibit apoptosis, induce proliferation and invoke terminal differentiation. Finally, during involution the mammary gland is exposed to milk stasis, programmed cell death and stromal reorganization to clear the differentiated milk-producing cells. Not surprisingly, the signaling pathways responsible for bringing about these changes in breast cells are often subverted during the process of tumorigenesis. The STAT family of proteins is involved in every stage of mammary gland development, and is also frequently implicated in breast tumorigenesis. While the roles of STAT3 and STAT5 during mammary gland development and tumorigenesis are well studied, others members, e.g. STAT1 and STAT6, have only recently been observed to play a role in mammary gland biology. Continued investigation into the STAT protein network in the mammary gland will likely yield new biomarkers and risk factors for breast cancer, and may also lead to novel prophylactic or therapeutic strategies against breast cancer.

  11. Developmental biology: cell fate in the mammary gland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most breast cancers have their origin in the luminal epithelial cells of the mammary gland. Defining how a master regulator controls the development of this cell lineage could provide important hints about why this should be. ...

  12. The mammary gland and its origin during synapsid evolution.

    PubMed

    Oftedal, Olav T

    2002-07-01

    Lactation appears to be an ancient reproductive trait that predates the origin of mammals. The synapsid branch of the amniote tree that separated from other taxa in the Pennsylvanian (>310 million years ago) evolved a glandular rather than scaled integument. Repeated radiations of synapsids produced a gradual accrual of mammalian features. The mammary gland apparently derives from an ancestral apocrine-like gland that was associated with hair follicles. This association is retained by monotreme mammary glands and is evident as vestigial mammary hair during early ontogenetic development of marsupials. The dense cluster of mammo-pilo-sebaceous units that open onto a nipple-less mammary patch in monotremes may reflect a structure that evolved to provide moisture and other constituents to permeable eggs. Mammary patch secretions were coopted to provide nutrients to hatchlings, but some constituents including lactose may have been secreted by ancestral apocrine-like glands in early synapsids. Advanced Triassic therapsids, such as cynodonts, almost certainly secreted complex, nutrient-rich milk, allowing a progressive decline in egg size and an increasingly altricial state of the young at hatching. This is indicated by the very small body size, presence of epipubic bones, and limited tooth replacement in advanced cynodonts and early mammaliaforms. Nipples that arose from the mammary patch rendered mammary hairs obsolete, while placental structures have allowed lactation to be truncated in living eutherians. PMID:12751889

  13. Inhibitory effects of a polypeptide thymic factor on the development of 7,12-dimethylbenz(a)anthragene-induced mammary adenocarcinoma in female rats

    SciTech Connect

    Anisimov, V.N.; Danetskaya, E.V.; Morozov, V.G.; Khavinson, V.Kh.

    1980-01-01

    It has come to be recognized that tumor growth is accompanied by inhibition of cellular immunity and the function of the T lymphocytes. Restitution of T lymphocyte function by means of several pharmacologic agents such as levamisole, phenformin, or epithalamin (an epiphyseal factor) has, in a number of cases, been accompanied by growth inhibition of both spontaneous and induced tumors. In addition, the importance of the thymus in the regulation of T lymphocytes and in antitumor immunity has been recognized. Several indicators point to the fact that the thymus contains physiologically active substances which stimulate T cell-dependent immunity and prevent the occurrence of neoplasms. These considerations have led to attempts at isolation of active thymic factors and studies on their effects on the appearance and growth of tumors. Previously, a thymic factor - thymarin - had been isolated which imparted immunocompetence to the T lymphocytes. This factor differs from other thymic preparations, including thymosine, in terms of a number of physicochemical characteristics and is a polypeptide with a molecular weight of 5000. This study is concerned with its effects on tumor development - mammary gland adenocarcinoma induced in animals with a chemical carcinogen.

  14. Sequencing the transcriptome of milk production: milk trumps mammary tissue

    PubMed Central

    2013-01-01

    Background Studies of normal human mammary gland development and function have mostly relied on cell culture, limited surgical specimens, and rodent models. Although RNA extracted from human milk has been used to assay the mammary transcriptome non-invasively, this assay has not been adequately validated in primates. Thus, the objectives of the current study were to assess the suitability of lactating rhesus macaques as a model for lactating humans and to determine whether RNA extracted from milk fractions is representative of RNA extracted from mammary tissue for the purpose of studying the transcriptome of milk-producing cells. Results We confirmed that macaque milk contains cytoplasmic crescents and that ample high-quality RNA can be obtained for sequencing. Using RNA sequencing, RNA extracted from macaque milk fat and milk cell fractions more accurately represented RNA from mammary epithelial cells (cells that produce milk) than did RNA from whole mammary tissue. Mammary epithelium-specific transcripts were more abundant in macaque milk fat, whereas adipose or stroma-specific transcripts were more abundant in mammary tissue. Functional analyses confirmed the validity of milk as a source of RNA from milk-producing mammary epithelial cells. Conclusions RNA extracted from the milk fat during lactation accurately portrayed the RNA profile of milk-producing mammary epithelial cells in a non-human primate. However, this sample type clearly requires protocols that minimize RNA degradation. Overall, we validated the use of RNA extracted from human and macaque milk and provided evidence to support the use of lactating macaques as a model for human lactation. PMID:24330573

  15. Ectodysplasin/NF-κB Promotes Mammary Cell Fate via Wnt/β-catenin Pathway

    PubMed Central

    Voutilainen, Maria; Lönnblad, Darielle; Shirokova, Vera; Elo, Teresa; Rysti, Elisa; Schmidt-Ullrich, Ruth; Schneider, Pascal; Mikkola, Marja L.

    2015-01-01

    Mammary gland development commences during embryogenesis with the establishment of a species typical number of mammary primordia on each flank of the embryo. It is thought that mammary cell fate can only be induced along the mammary line, a narrow region of the ventro-lateral skin running from the axilla to the groin. Ectodysplasin (Eda) is a tumor necrosis factor family ligand that regulates morphogenesis of several ectodermal appendages. We have previously shown that transgenic overexpression of Eda (K14-Eda mice) induces formation of supernumerary mammary placodes along the mammary line. Here, we investigate in more detail the role of Eda and its downstream mediator transcription factor NF-κB in mammary cell fate specification. We report that K14-Eda mice harbor accessory mammary glands also in the neck region indicating wider epidermal cell plasticity that previously appreciated. We show that even though NF-κB is not required for formation of endogenous mammary placodes, it is indispensable for the ability of Eda to induce supernumerary placodes. A genome-wide profiling of Eda-induced genes in mammary buds identified several Wnt pathway components as potential transcriptional targets of Eda. Using an ex vivo culture system, we show that suppression of canonical Wnt signalling leads to a dose-dependent inhibition of supernumerary placodes in K14-Eda tissue explants. PMID:26581094

  16. Ectodysplasin/NF-κB Promotes Mammary Cell Fate via Wnt/β-catenin Pathway.

    PubMed

    Voutilainen, Maria; Lindfors, Päivi H; Trela, Ewelina; Lönnblad, Darielle; Shirokova, Vera; Elo, Teresa; Rysti, Elisa; Schmidt-Ullrich, Ruth; Schneider, Pascal; Mikkola, Marja L

    2015-11-01

    Mammary gland development commences during embryogenesis with the establishment of a species typical number of mammary primordia on each flank of the embryo. It is thought that mammary cell fate can only be induced along the mammary line, a narrow region of the ventro-lateral skin running from the axilla to the groin. Ectodysplasin (Eda) is a tumor necrosis factor family ligand that regulates morphogenesis of several ectodermal appendages. We have previously shown that transgenic overexpression of Eda (K14-Eda mice) induces formation of supernumerary mammary placodes along the mammary line. Here, we investigate in more detail the role of Eda and its downstream mediator transcription factor NF-κB in mammary cell fate specification. We report that K14-Eda mice harbor accessory mammary glands also in the neck region indicating wider epidermal cell plasticity that previously appreciated. We show that even though NF-κB is not required for formation of endogenous mammary placodes, it is indispensable for the ability of Eda to induce supernumerary placodes. A genome-wide profiling of Eda-induced genes in mammary buds identified several Wnt pathway components as potential transcriptional targets of Eda. Using an ex vivo culture system, we show that suppression of canonical Wnt signalling leads to a dose-dependent inhibition of supernumerary placodes in K14-Eda tissue explants. PMID:26581094

  17. Ectodysplasin/NF-κB Promotes Mammary Cell Fate via Wnt/β-catenin Pathway.

    PubMed

    Voutilainen, Maria; Lindfors, Päivi H; Trela, Ewelina; Lönnblad, Darielle; Shirokova, Vera; Elo, Teresa; Rysti, Elisa; Schmidt-Ullrich, Ruth; Schneider, Pascal; Mikkola, Marja L

    2015-11-01

    Mammary gland development commences during embryogenesis with the establishment of a species typical number of mammary primordia on each flank of the embryo. It is thought that mammary cell fate can only be induced along the mammary line, a narrow region of the ventro-lateral skin running from the axilla to the groin. Ectodysplasin (Eda) is a tumor necrosis factor family ligand that regulates morphogenesis of several ectodermal appendages. We have previously shown that transgenic overexpression of Eda (K14-Eda mice) induces formation of supernumerary mammary placodes along the mammary line. Here, we investigate in more detail the role of Eda and its downstream mediator transcription factor NF-κB in mammary cell fate specification. We report that K14-Eda mice harbor accessory mammary glands also in the neck region indicating wider epidermal cell plasticity that previously appreciated. We show that even though NF-κB is not required for formation of endogenous mammary placodes, it is indispensable for the ability of Eda to induce supernumerary placodes. A genome-wide profiling of Eda-induced genes in mammary buds identified several Wnt pathway components as potential transcriptional targets of Eda. Using an ex vivo culture system, we show that suppression of canonical Wnt signalling leads to a dose-dependent inhibition of supernumerary placodes in K14-Eda tissue explants.

  18. ApcMin, A Mutation in the Murine Apc Gene, Predisposes to Mammary Carcinomas and Focal Alveolar Hyperplasias

    NASA Astrophysics Data System (ADS)

    Moser, Amy Rapaich; Mattes, Ellen M.; Dove, William F.; Lindstrom, Mary J.; Haag, Jill D.; Gould, Michael N.

    1993-10-01

    ApcMin (Min, multiple intestinal neoplasia) is a point mutation in the murine homolog of the APC gene. Min/+ mice develop multiple intestinal adenomas, as do humans carrying germ-line mutations in APC. Female mice carrying Min are also prone to develop mammary tumors. Min/+ mammary glands are more sensitive to chemical carcinogenesis than are +/+ mammary glands. Transplantation of mammary cells from Min/+ or +/+ donors into +/+ hosts demonstrates that the propensity to develop mammary tumors is intrinsic to the Min/+ mammary cells. Long-term grafts of Min/+ mammary glands also gave rise to focal alveolar hyperplasias, indicating that the presence of the Min mutation also has a role in the development of these lesions.

  19. The Ca2+/H+ antiporter TMEM165 expression, localization in the developing, lactating and involuting mammary gland parallels the secretory pathway Ca2+ATPase (SPCA1)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plasma membrane Ca2+-ATPase 2 (PMCA2) knockout mice showed that ~ 60 % of calcium in milk is transported across the mammary cells apical membrane by PMCA2. The remaining milk calcium is thought to arrive via the secretory pathway through the actions of secretory pathway Ca2+-ATPase’s 1 and/or 2 (SP...

  20. Technical note: Isolation and characterization of porcine mammary epithelial cells.

    PubMed

    Dahanayaka, S; Rezaei, R; Porter, W W; Johnson, G A; Burghardt, R C; Bazer, F W; Hou, Y Q; Wu, Z L; Wu, G

    2015-11-01

    Within the mammary gland, functional synthesis of milk is performed by its epithelial (alveolar) cells. The availability of a stable mammary epithelial cell line is essential for biochemical studies to elucidate cellular and molecular mechanisms responsible for nutritional regulation of lactation. Therefore, porcine mammary epithelial cells (PMEC) were isolated from mammary glands of a 9-mo-old nonpregnant and nonlactating gilt and cultured to establish a nonimmortalized cell line. These cells were characterized by expression of cytokeratin-18 (an intermediate filament specific for epithelial cells), β-casein (a specific marker for mammary epithelial cells), and α-lactalbumin. In culture, the PMEC doubled in number every 24 h and maintained a cobblestone morphology, typical for cultured epithelial cells, for at least 15 passages. Addition of 0.2 to 2 μg/mL prolactin to culture medium for 3 d induced the production of β-casein and α-lactalbumin by PMEC in a dose-dependent manner. Thus, we have successfully developed a useful PMEC line for future studies of cellular and molecular regulation of milk synthesis by mammary epithelial cells of the sow. PMID:26641038

  1. Neuropilin-2 promotes branching morphogenesis in the mouse mammary gland.

    PubMed

    Goel, Hira Lal; Bae, Donggoo; Pursell, Bryan; Gouvin, Lindsey M; Lu, Shaolei; Mercurio, Arthur M

    2011-07-01

    Although the neuropilins were characterized as semaphorin receptors that regulate axon guidance, they also function as vascular endothelial growth factor (VEGF) receptors and contribute to the development of other tissues. Here, we assessed the role of NRP2 in mouse mammary gland development based on our observation that NRP2 is expressed preferentially in the terminal end buds of developing glands. A floxed NRP2 mouse was bred with an MMTV-Cre strain to generate a mammary gland-specific knockout of NRP2. MMTV-Cre;NRP2(loxP/loxP) mice exhibited significant defects in branching morphogenesis and ductal outgrowth compared with either littermate MMTV-Cre;NRP2(+/loxP) or MMTV-Cre mice. Mechanistic insight into this morphological defect was obtained from a mouse mammary cell line in which we observed that VEGF(165), an NRP2 ligand, induces branching morphogenesis in 3D cultures and that branching is dependent upon NRP2 as shown using shRNAs and a function-blocking antibody. Epithelial cells in the mouse mammary gland express VEGF, supporting the hypothesis that this NRP2 ligand contributes to mammary gland morphogenesis. Importantly, we demonstrate that VEGF and NRP2 activate focal adhesion kinase (FAK) and promote FAK-dependent branching morphogenesis in vitro. The significance of this mechanism is substantiated by our finding that FAK activation is diminished significantly in developing MMTV-Cre;NRP2(loxP/loxP) mammary glands compared with control glands. Together, our data reveal a VEGF/NRP2/FAK signaling axis that is important for branching morphogenesis and mammary gland development. In a broader context, our data support an emerging hypothesis that directional outgrowth and branching morphogenesis in a variety of tissues are influenced by signals that were identified initially for their role in axon guidance.

  2. Vitamin D(3) receptor ablation alters mammary gland morphogenesis.

    PubMed

    Zinser, Glendon; Packman, Kathryn; Welsh, JoEllen

    2002-07-01

    Postnatal mammary gland morphogenesis is achieved through coordination of signaling networks in both the epithelial and stromal cells of the developing gland. While the major proliferative hormones driving pubertal mammary gland development are estrogen and progesterone, studies in transgenic and knockout mice have successfully identified other steroid and peptide hormones that impact on mammary gland development. The vitamin D(3) receptor (VDR), whose ligand 1,25-dihydroxyvitamin D(3) is the biologically active form of vitamin D(3), has been implicated in control of differentiation, cell cycle and apoptosis of mammary cells in culture, but little is known about the physiological relevance of the vitamin D(3) endocrine system in the developing gland. In these studies, we report the expression of the VDR in epithelial cells of the terminal end bud and subtending ducts, in stromal cells and in a subset of lymphocytes within the lymph node. In the terminal end bud, a distinct gradient of VDR expression is observed, with weak VDR staining in proliferative populations and strong VDR staining in differentiated populations. The role of the VDR in ductal morphogenesis was examined in Vdr knockout mice fed high dietary Ca(2+) which normalizes fertility, serum estrogen and neonatal growth. Our results indicate that mammary glands from virgin Vdr knockout mice are heavier and exhibit enhanced growth, as evidenced by higher numbers of terminal end buds, greater ductal outgrowth and enhanced secondary branch points, compared with glands from age- and weight-matched wild-type mice. In addition, glands from Vdr knockout mice exhibit enhanced growth in response to exogenous estrogen and progesterone, both in vivo and in organ culture, compared with glands from wild-type mice. Our data provide the first in vivo evidence that 1,25-dihydroxyvitamin D(3) and the VDR impact on ductal elongation and branching morphogenesis during pubertal development of the mammary gland. Collectively

  3. Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

    PubMed Central

    Tilli, Maddalena T; Parrish, Angela R; Cotarla, Ion; Jones, Laundette P; Johnson, Michael D; Furth, Priscilla A

    2008-01-01

    Background Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. Methods We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. Results In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. Conclusion In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary. PMID:18215290

  4. ΔNp63 promotes stem cell activity in mammary gland development and basal-like breast cancer by enhancing Fzd7 expression and Wnt signalling.

    PubMed

    Chakrabarti, Rumela; Wei, Yong; Hwang, Julie; Hang, Xiang; Andres Blanco, Mario; Choudhury, Abrar; Tiede, Benjamin; Romano, Rose-Anne; DeCoste, Christina; Mercatali, Laura; Ibrahim, Toni; Amadori, Dino; Kannan, Nagarajan; Eaves, Connie J; Sinha, Satrajit; Kang, Yibin

    2014-10-01

    Emerging evidence suggests that cancer is populated and maintained by tumour-initiating cells (TICs) with stem-like properties similar to those of adult tissue stem cells. Despite recent advances, the molecular regulatory mechanisms that may be shared between normal and malignant stem cells remain poorly understood. Here we show that the ΔNp63 isoform of the Trp63 transcription factor promotes normal mammary stem cell (MaSC) activity by increasing the expression of the Wnt receptor Fzd7, thereby enhancing Wnt signalling. Importantly, Fzd7-dependent enhancement of Wnt signalling by ΔNp63 also governs tumour-initiating activity of the basal subtype of breast cancer. These findings establish ΔNp63 as a key regulator of stem cells in both normal and malignant mammary tissues and provide direct evidence that breast cancer TICs and normal MaSCs share common regulatory mechanisms.

  5. Genes affected by mouse mammary tumor virus (MMTV) proviral insertions in mouse mammary tumors are deregulated or mutated in primary human mammary tumors

    PubMed Central

    Callahan, Robert; Mudunuri, Uma; Bargo, Sharon; Raafat, Ahmed; McCurdy, David; Boulanger, Corinne; Lowther, William; Stephens, Robert; Luke, Brian T.; Stewart, Claudia; Wu, Xiaolin; Munroe, David; Smith, Gilbert H.

    2012-01-01

    The accumulation of mutations is a contributing factor in the initiation of premalignant mammary lesions and their progression to malignancy and metastasis. We have used a mouse model in which the carcinogen is the mouse mammary tumor virus (MMTV) which induces clonal premalignant mammary lesions and malignant mammary tumors by insertional mutagenesis. Identification of the genes and signaling pathways affected in MMTV-induced mouse mammary lesions provides a rationale for determining whether genetic alteration of the human orthologues of these genes/pathways may contribute to human breast carcinogenesis. A high-throughput platform for inverse PCR to identify MMTV-host junction fragments and their nucleotide sequences in a large panel of MMTV-induced lesions was developed. Validation of the genes affected by MMTV-insertion was carried out by microarray analysis. Common integration site (CIS) means that the gene was altered by an MMTV proviral insertion in at least two independent lesions arising in different hosts. Three of the new genes identified as CIS for MMTV were assayed for their capability to confer on HC11 mouse mammary epithelial cells the ability for invasion, anchorage independent growth and tumor development in nude mice. Analysis of MMTV induced mammary premalignant hyperplastic outgrowth (HOG) lines and mammary tumors led to the identification of CIS restricted to 35 loci. Within these loci members of the Wnt, Fgf and Rspo gene families plus two linked genes (Npm3 and Ddn) were frequently activated in tumors induced by MMTV. A second group of 15 CIS occur at a low frequency (2-5 observations) in mammary HOGs or tumors. In this latter group the expression of either Phf19 or Sdc2 was shown to increase HC11 cells invasion capability. Foxl1 expression conferred on HC11 cells the capability for anchorage-independent colony formation in soft agar and tumor development in nude mice. The published transcriptome and nucleotide sequence analysis of gene

  6. Unexpected severe consequences of Pikfyve deletion by aP2- or Aq-promoter-driven Cre expression for glucose homeostasis and mammary gland development.

    PubMed

    Ikonomov, Ognian C; Sbrissa, Diego; Delvecchio, Khortnal; Rillema, James A; Shisheva, Assia

    2016-06-01

    Systemic deficiency of PIKfyve, the evolutionarily conserved phosphoinositide kinase synthesizing cellular PtdIns5P and PtdIns(3,5)P2 and implicated in insulin signaling, causes early embryonic death in mice. In contrast, mice with muscle-specific Pikfyve disruption have normal lifespan but exhibit early-age whole-body glucose intolerance and muscle insulin resistance, thus establishing the key role of muscle PIKfyve in glucose homeostasis. Fat and muscle tissues control postprandial glucose clearance through different mechanisms, raising questions as to whether adipose Pikfyve disruption will also trigger whole-body metabolic abnormalities, and if so, what the mechanism might be. To clarify these issues, here we have characterized two new mouse models with adipose tissue disruption of Pikfyve through Cre recombinase expression driven by adipose-specific aP2- or adiponectin (Aq) promoters. Whereas both mouse lines were ostensibly normal until adulthood, their glucose homeostasis and systemic insulin sensitivity were severely dysregulated. These abnormalities stemmed in part from accelerated fat-cell lipolysis and elevated serum FFA Intriguingly, aP2-Cre-PIKfyve(fl/fl) but not Aq-Cre-PIKfyve(fl/fl) females had severely impaired pregnancy-induced mammary gland differentiation and lactogenesis, consistent with aP2-Cre-mediated Pikfyve excision in nonadipogenic tissues underlying this defect. Intriguingly, whereas mammary glands from postpartum control and Aq-Cre-PIKfyve(fl/fl) mice or ex vivo mammary gland explants showed profound upregulation of PIKfyve protein levels subsequent to prolactin receptor activation, such increases were not apparent in aP2-Cre-PIKfyve(fl/fl) females. Collectively, our data identify for the first time that adipose tissue Pikfyve plays a key role in the mechanisms regulating glucose homeostasis and that the PIKfyve pathway is critical in mammary epithelial differentiation during pregnancy and lactogenesis downstream of prolactin receptor

  7. Mammary Analogue Secretory Carcinoma.

    PubMed

    Stevens, Todd M; Parekh, Vishwas

    2016-09-01

    Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor that shares the same histologic appearance and ETV6 gene (12p13) rearrangement as secretory carcinoma of the breast. Prior to its recognition, MASC cases were commonly labeled acinic cell carcinoma and adenocarcinoma, not otherwise specified. Despite distinctive histologic features, MASC may be difficult to distinguish from other salivary gland tumors, in particular zymogen-poor acinic cell carcinoma and low-grade salivary duct carcinoma. Although characteristic morphologic and immunohistochemical features form the basis of a diagnosis of MASC, the presence of an ETV6-NTRK3 gene fusion is confirmatory. Given its recent recognition the true prognostic import of MASC is not yet clearly defined. PMID:27575269

  8. Growth hormone mRNA in mammary gland tumors of dogs and cats.

    PubMed Central

    Mol, J A; van Garderen, E; Selman, P J; Wolfswinkel, J; Rijinberk, A; Rutteman, G R

    1995-01-01

    We have shown recently that in the dog progestin administration results in mammary production of immunoreactive growth hormone (GH). At present we demonstrate the expression of the gene encoding GH in the mammary gland of dogs and cats using reverse-transcriptase PCR. GH mRNA was found in the great majority of normal mammary tissues as well as benign and malignant mammary tumors of the dog and was associated with the presence of immunoreactive GH in cryostat sections. The mammary PCR product proved to be identical to that of the pituitary. The highest expression levels were found after prolonged treatment with progestins. In carcinomas GH mRNA was also found in progesterone receptor-negative tissue samples, indicating that after malignant transformation GH gene expression may become progestin independent. GH mRNA was also present in mammary tissues of cats with progestin-induced fibroadenomatous changes. It is concluded that GH gene expression occurs in normal, hyperplastic, and neoplastic mammary tissue of the dog. The expression in normal tissue is stimulated by progestins and might mediate the progestin-stimulated development of canine mammary tumors. The demonstration of progestin-stimulated GH expression in mammary tissue of cats indicates that the phenomenon is more generalized among mammals. Images PMID:7738169

  9. Optimization and characterization of an in vitro bovine mammary cell culture system to study regulation of milk protein synthesis and mammary differentiation

    SciTech Connect

    Talhouk, R.S.

    1988-01-01

    A long term bovine mammary cell culture system that maintains normal mammary cell function was established and optimized to study milk protein synthesis and secretion and mammary differentiation. This culture system used bovine mammary acini isolated from developing or lactating mammary gland by enzymatic dissociation, and cryopreserved until thawed and plated for growth in vitro for these studies. Cells in M199 with lactogenic hormones {plus minus} fetal calf serum (FCS) were cultured on plastic, 100ul and 500ul type I collagen, and Matrigel, or embedded within type I collagen. Cell morphology, cell number, and total TCA-precipitable {sup 35}S-labelled proteins were monitored. Milk protein ({alpha}{sub s,1}-casein, lactoferrin (LF), {alpha}-lactalbumin, and {beta}-lactoglobulin) secretion and intracellular levels were determined by an ELISA assay.

  10. Hormonal regulation of the immune microenvironment in the mammary gland.

    PubMed

    Need, Eleanor F; Atashgaran, Vahid; Ingman, Wendy V; Dasari, Pallave

    2014-07-01

    It is well established that the development and homeostasis of the mammary gland are highly dependent upon the actions of ovarian hormones progesterone and estrogen, as well as the availability of prolactin for the pregnant and lactating gland. More recently it has become apparent that immune system cells and cytokines play essential roles in both mammary gland development as well as breast cancer. Here, we review hormonal effects on mammary gland biology during puberty, menstrual cycling, pregnancy, lactation and involution, and dissect how hormonal control of the immune system may contribute to mammary development at each stage via cytokine secretion and recruitment of macrophages, eosinophils, mast cells and lymphocytes. Collectively, these alterations may create an immunotolerant or inflammatory immune environment at specific developmental stages or phases of the menstrual cycle. Of particular interest for further research is investigation of the combinatorial actions of progesterone and estrogen during the luteal phase of the menstrual cycle and key developmental points where the immune system may play an active role both in mammary development as well as in the creation of an immunotolerant environment, thereby affecting breast cancer risk.

  11. Presence of hyperplastic pectoral mammary glands in a white-footed mouse (Peromyscus leucopus) from a Superfund Site in Oklahoma, USA.

    PubMed

    Hays, Kimberly A; Breshears, Melanie A

    2011-01-01

    Laboratory experiments have documented the effects of hormones and endocrine-disrupting compounds on mammary development in mammals. However, few observations of mammary hyperplasia have been presented for wild rodents. We describe hyperplastic mammary glands in a wild-caught white-footed mouse (Peromyscus leucopus) from an area contaminated with heavy metals. PMID:21270018

  12. Presence of hyperplastic pectoral mammary glands in a white-footed mouse (Peromyscus leucopus) from a Superfund Site in Oklahoma, USA.

    PubMed

    Hays, Kimberly A; Breshears, Melanie A

    2011-01-01

    Laboratory experiments have documented the effects of hormones and endocrine-disrupting compounds on mammary development in mammals. However, few observations of mammary hyperplasia have been presented for wild rodents. We describe hyperplastic mammary glands in a wild-caught white-footed mouse (Peromyscus leucopus) from an area contaminated with heavy metals.

  13. Insulin receptors in the mammary gland

    SciTech Connect

    Smith, D.H.

    1986-01-01

    Insulin binding studies were conducted using mammary membrane preparations to further the authors understanding of insulin's role in regulating mammary metabolism, particularly ruminant mammary metabolism. Specific objectives were to: (1) characterize insulin binding to bovine mammary microsomes and determine if the specificity and kinetics of binding indicate the presence of insulin receptors in bovine mammary gland; (2) examine and compare insulin binding by liver and mammary microsomes of the pig and dairy cow; (3) examine insulin binding to bovine milk fat globule membranes (MFGM) and evaluate this model's usefulness in assessing insulin receptor regulation in the mammary gland of the cow; (4) examine the effect of dietary fat in insulin binding by rat mammary and liver microsomes. The specificity and kinetics of /sup 125/I-insulin binding of bovine mammary microsomes indicated the presence of insulin receptors in bovine mammary gland. Bovine liver and mammary microsomes specifically bound less /sup 125/I-insulin than did the corresponding porcine microsomes, and mammary microsomes, regardless of species, specifically bound less /sup 125/I-insulin than did liver microsomes. These differences in binding suggest differences in insulin responsiveness between pigs and cattle, as well as between the liver and mammary glands.

  14. Repression of mammary adipogenesis by genistein limits mammosphere formation of human MCF-7 cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mammary adipose tissue may contribute to breast cancer development and progression by altering neighboring epithelial cell behavior and phenotype through paracrine signaling. Dietary exposure to soy foods is associated with lower mammary tumor risk and reduced body weight and adiposity in humans and...

  15. Symposium: Role of the extracellular matrix in mammary development. Regulation of milk protein and basement membrane gene expression: The influence of the extracellular matrix

    SciTech Connect

    Aggeler, J.; Park, C.S.; Bissell, M.J.

    1988-10-01

    Synthesis and secretion of milk proteins ({alpha}-casein, {beta}-casein, {gamma}-casein, and transferrin) by cultured primary mouse mammary epithelial cells is modulated by the extracellular matrix. In cells grown on released or floating type I collagen gels, mRNA for {beta}-casein and transferrin is increased as much as 30-fold over cells grown on plastic. Induction of {beta}-casein expression depends strongly on the presence of lactogenic hormones, especially prolactin, in the culture. When cells are plated onto partially purified reconstituted basement membrane, dramatic changes in morphology and milk protein gene expression are observed. Cells cultured on the matrix for 6 to 8 d in the presence of prolactin, insulin, and hydrocortisone form hollow spheres and duct-like structures that are completely surrounded by matrix. The cells lining these spheres appear actively secretory and are oriented with their apices facing the lumen. Hybridization experiments indicate that mRNA for {beta}-casein can be increased as much as 70-fold in these cultures. Because > 90% of the cultured cells synthesize immunoreactive {beta}-casein, as compared with only 40% of cells in the late pregnant gland, the matrix appears to be able to induce protein expression in previously silent cells. Synthesis of laminin and assembly of a mammary-specific basal lamina by cells cultured on different extracellular matrices also appears to depend on the presence of lactogenic hormones. These studies provide support for the concept of dynamic reciprocity in which complex interactions between extracellular matrix and the cellular cytoskeleton contribute to the induction and maintenance of tissue-specific gene expression in the mammary gland.

  16. Insights into the role of connexins in mammary gland morphogenesis and function.

    PubMed

    Stewart, Michael K G; Simek, Jamie; Laird, Dale W

    2015-06-01

    Gap junctions formed of connexin subunits link adjacent cells by direct intercellular communication that is essential for normal tissue homeostasis in the mammary gland. The mammary gland undergoes immense remodeling and requires exquisite regulation to control the proliferative, differentiating, and cell death mechanisms regulating gland development and function. The generation of novel genetically modified mice with reduced or ablated connexin function within the mammary gland has advanced our understanding of the role of gap junctions during the complex and dynamic process of mammary gland development. These studies have revealed an important stage-specific role for Cx26 (GJA1) and Cx43 (GJB2), while Cx30 (GJB6) and Cx32 (Gjb1) can be eliminated without compromising the gland. Yet, there remain gaps in our understanding of the role of mammary gland gap junctions.

  17. [Progress of Japan Mammary Cancer Society and future perspectives].

    PubMed

    Kuno, K

    1985-05-01

    One of the important past achievements of the Japan Mammary Cancer Society was the establishment of the general rule for clinical and pathological record of mammary cancer. The past two decades have seen major changes in our understanding of the biology of the breast cancer as well as in diagnosis and management. The prediction of the future is extremely difficult. However, there is a future need to develop tests of tumor and host potential for spread. A future goal of chemotherapy selectivity would be to develop ways of testing for drug selection.

  18. Isolation of Endoplasmic Reticulum Fractions from Mammary Epithelial Tissue.

    PubMed

    Chanat, Eric; Le Parc, Annabelle; Lahouassa, Hichem; Badaoui, Bouabid

    2016-06-01

    In the mammary glands of lactating animals, the mammary epithelial cells that surround the lumen of the acini produce and secrete copious amounts of milk. Functional differentiation of these mammary epithelial cells depends on the development of high-efficiency secretory pathways, notably for protein and lipid secretion. Protein secretion is a fundamental process common to all animal cells that involves a subset of cellular organelles, including the endoplasmic reticulum and the Golgi apparatus. In contrast, en masse secretion of triglycerides and cholesterol esters in the form of milk fat globules is a unique feature of the mammary epithelial cell. Cytoplasmic lipid droplets, the intracellular precursors of milk fat globules, originate from the endoplasmic reticulum, as do most milk-specific proteins. This organelle is therefore pivotal in the biogenesis of milk components. Fractionation of the cell into its subcellular parts is an approach that has proven very powerful for understanding organelle function and for studying the specific role of an organelle in a given cell activity. Here we describe a method for the purification of both smooth and rough microsomes, the membrane-bound endoplasmic reticulum fragments that form from endoplasmic reticulum domains when cells are broken up, from mammary gland tissue at lactation.

  19. Int-6, a highly conserved, widely expressed gene, is mutated by mouse mammary tumor virus in mammary preneoplasia.

    PubMed Central

    Marchetti, A; Buttitta, F; Miyazaki, S; Gallahan, D; Smith, G H; Callahan, R

    1995-01-01

    With a unique mouse mammary tumor model system in which mouse mammary tumor virus (MMTV) insertional mutations can be detected during progression from preneoplasia to frank malignancy, including metastasis, we have discovered a new common integration site (designated Int-6) for MMTV in mouse mammary tumors. MMTV was integrated into Int-6 in a mammary hyperplastic outgrowth line, its tumors and metastases, and two independent mammary tumors arising in unrelated mice. The Int-6 gene is ubiquitously expressed as a 1.4-kb RNA species in adult tissues and is detected beginning at day 8 of embryonic development. The nucleotide sequence of Int-6 is unrelated to any of the known genes in the GenBank database. MMTV integrates within introns of the gene in the opposite transcriptional orientation. In each tumor tested, this results in the expression of a truncated Int-6/long terminal repeat (LTR) chimeric RNA species which is terminated at a cryptic termination signal in the MMTV LTR. Since the nonrearranged Int-6 alleles in these tumors contain no mutations, we favor the conclusion that truncation of the Int-6 gene product either biologically activates its function or represents a dominant-negative mutation. PMID:7853537

  20. Idiopathic internal mammary artery aneurysm

    PubMed Central

    Heyn, Jens; Zimmermann, Hanna; Klose, Alexander; Luchting, Benjamin; Hinske, Christian; Sadeghi-Azandaryani, Mojtaba

    2014-01-01

    Aneurysms of the internal mammary artery are extremely rare, and their presentation and treatment are variable. Since these aneurysms often tend to rupture and cause haemothorax and life-threatening conditions, the knowledge of secure treatment options is indispensable. We here report the case of an idiopathic internal mammary aneurysm in a 46-year-old man. Open surgical resection of the aneurysm was performed in this case without any complications. The postoperative course was uneventful and the patient was in a good physical condition without any vascular or neurological abnormalities during follow-up. PMID:25452261

  1. Sox10 Regulates Stem/Progenitor and Mesenchymal Cell States in Mammary Epithelial Cells.

    PubMed

    Dravis, Christopher; Spike, Benjamin T; Harrell, J Chuck; Johns, Claire; Trejo, Christy L; Southard-Smith, E Michelle; Perou, Charles M; Wahl, Geoffrey M

    2015-09-29

    To discover mechanisms that mediate plasticity in mammary cells, we characterized signaling networks that are present in the mammary stem cells responsible for fetal and adult mammary development. These analyses identified a signaling axis between FGF signaling and the transcription factor Sox10. Here, we show that Sox10 is specifically expressed in mammary cells exhibiting the highest levels of stem/progenitor activity. This includes fetal and adult mammary cells in vivo and mammary organoids in vitro. Sox10 is functionally relevant, as its deletion reduces stem/progenitor competence whereas its overexpression increases stem/progenitor activity. Intriguingly, we also show that Sox10 overexpression causes mammary cells to undergo a mesenchymal transition. Consistent with these findings, Sox10 is preferentially expressed in stem- and mesenchymal-like breast cancers. These results demonstrate a signaling mechanism through which stem and mesenchymal states are acquired in mammary cells and suggest therapeutic avenues in breast cancers for which targeted therapies are currently unavailable. PMID:26365194

  2. Activation of Mammalian target of rapamycin in canine mammary carcinomas: an immunohistochemical study.

    PubMed

    Delgado, L; Gärtner, F; Dias Pereira, P

    2015-01-01

    Mammalian target of rapamycin (mTOR) is a serine-threonine kinase involved in cell growth, proliferation and survival. Activation of mTOR has been reported in various tumour types, including human breast cancer; however, the expression of mTOR in canine mammary tumours has not been examined. In the present study, expression of the activated form of mTOR (phospho-mTOR [p-mTOR]) was examined immunohistochemically in five normal canine mammary glands, 45 canine mammary carcinomas and their corresponding metastatic lesions (n = 15). Phospho-mTOR was not expressed in normal canine mammary tissue, but cytoplasmic labelling was observed in 78% of canine mammary carcinomas. Two carcinomas had both cytoplasmic and nuclear labelling. No significant relationship was found between p-mTOR cytoplasmic expression and histological type or grading of carcinomas, degree of tubular formation, anisokaryosis, mitotic activity or lymph node metastasis. In all except one case, the expression pattern of p-mTOR in lymph node metastases was similar or decreased when compared with the primary lesion. The findings suggest that p-mTOR is involved in mammary carcinogenesis in dogs. However, p-mTOR cytoplasmic expression does not appear to be a prognostic indicator in canine mammary carcinomas, which may be related to its subcellular location in the neoplastic cells. Canine mammary tumours may provide a model for the development of innovative medical strategies involving mTOR inhibitors in human breast cancer. PMID:25670666

  3. Site-specific inductive and inhibitory activities of MMP-2 and MMP-3 orchestrate mammary gland branching morphogenesis

    PubMed Central

    Wiseman, Bryony S.; Sternlicht, Mark D.; Lund, Leif R.; Alexander, Caroline M.; Mott, Joni; Bissell, Mina J.; Soloway, Paul; Itohara, Shigeyoshi; Werb, Zena

    2003-01-01

    During puberty, mouse mammary epithelial ducts invade the stromal mammary fat pad in a wave of branching morphogenesis to form a complex ductal tree. Using pharmacologic and genetic approaches, we find that mammary gland branching morphogenesis requires transient matrix metalloproteinase (MMP) activity for invasion and branch point selection. MMP-2, but not MMP-9, facilitates terminal end bud invasion by inhibiting epithelial cell apoptosis at the start of puberty. Unexpectedly, MMP-2 also represses precocious lateral branching during mid-puberty. In contrast, MMP-3 induces secondary and tertiary lateral branching of ducts during mid-puberty and early pregnancy. Nevertheless, the mammary gland is able to develop lactational competence in MMP mutant mice. Thus, specific MMPs refine the mammary branching pattern by distinct mechanisms during mammary gland branching morphogenesis. PMID:12975354

  4. Phenotypic and Molecular Alterations in the Mammary Tissue of R-Spondin1 Knock-Out Mice during Pregnancy

    PubMed Central

    Chadi, Sead; Polyte, Jacqueline; Lefevre, Lucas; Castille, Johan; Ehanno, Aude; Laubier, Johann; Jaffrézic, Florence; Le Provost, Fabienne

    2016-01-01

    R-spondin1 (Rspo1) is a member of a secreted protein family which has pleiotropic functions in development and stem cell growth. Rspo1 knock-out mice are sex-reversed, but some remain sub-fertile, so they fail to nurse their pups. A lack of Rspo1 expression in the mammary gland results in an absence of duct side-branching development and defective alveolar formation. The aim of this study was to characterize the phenotypic and molecular alterations of mammary gland due to Rspo1 knock-out. Using the transcriptional profiling of mammary tissues, we identified misregulated genes in the mammary gland of Rspo1 knock-out mice during pregnancy. A stronger expression of mesenchymal markers was observed, without modifications to the structure of mammary epithelial tissue. Mammary epithelial cell immunohistochemical analysis revealed a persistence of virgin markers, which signify a delay in cell differentiation. Moreover, serial transplantation experiments showed that Rspo1 is associated with a regenerative potential of mammary epithelial cell control. Our finding also highlights the negatively regulated expression of Rspo1’s partners, Lgr4 and RNF43, in the mammary gland during pregnancy. Moreover, we offer evidence that Tgf-β signalling is modified in the absence of Rspo1. Taken together, our results show an abrupt halt or delay to mammary development during pregnancy due to the loss of a further differentiated function. PMID:27611670

  5. Phenotypic and Molecular Alterations in the Mammary Tissue of R-Spondin1 Knock-Out Mice during Pregnancy.

    PubMed

    Chadi, Sead; Polyte, Jacqueline; Lefevre, Lucas; Castille, Johan; Ehanno, Aude; Laubier, Johann; Jaffrézic, Florence; Le Provost, Fabienne

    2016-01-01

    R-spondin1 (Rspo1) is a member of a secreted protein family which has pleiotropic functions in development and stem cell growth. Rspo1 knock-out mice are sex-reversed, but some remain sub-fertile, so they fail to nurse their pups. A lack of Rspo1 expression in the mammary gland results in an absence of duct side-branching development and defective alveolar formation. The aim of this study was to characterize the phenotypic and molecular alterations of mammary gland due to Rspo1 knock-out. Using the transcriptional profiling of mammary tissues, we identified misregulated genes in the mammary gland of Rspo1 knock-out mice during pregnancy. A stronger expression of mesenchymal markers was observed, without modifications to the structure of mammary epithelial tissue. Mammary epithelial cell immunohistochemical analysis revealed a persistence of virgin markers, which signify a delay in cell differentiation. Moreover, serial transplantation experiments showed that Rspo1 is associated with a regenerative potential of mammary epithelial cell control. Our finding also highlights the negatively regulated expression of Rspo1's partners, Lgr4 and RNF43, in the mammary gland during pregnancy. Moreover, we offer evidence that Tgf-β signalling is modified in the absence of Rspo1. Taken together, our results show an abrupt halt or delay to mammary development during pregnancy due to the loss of a further differentiated function.

  6. Phenotypic and Molecular Alterations in the Mammary Tissue of R-Spondin1 Knock-Out Mice during Pregnancy.

    PubMed

    Chadi, Sead; Polyte, Jacqueline; Lefevre, Lucas; Castille, Johan; Ehanno, Aude; Laubier, Johann; Jaffrézic, Florence; Le Provost, Fabienne

    2016-01-01

    R-spondin1 (Rspo1) is a member of a secreted protein family which has pleiotropic functions in development and stem cell growth. Rspo1 knock-out mice are sex-reversed, but some remain sub-fertile, so they fail to nurse their pups. A lack of Rspo1 expression in the mammary gland results in an absence of duct side-branching development and defective alveolar formation. The aim of this study was to characterize the phenotypic and molecular alterations of mammary gland due to Rspo1 knock-out. Using the transcriptional profiling of mammary tissues, we identified misregulated genes in the mammary gland of Rspo1 knock-out mice during pregnancy. A stronger expression of mesenchymal markers was observed, without modifications to the structure of mammary epithelial tissue. Mammary epithelial cell immunohistochemical analysis revealed a persistence of virgin markers, which signify a delay in cell differentiation. Moreover, serial transplantation experiments showed that Rspo1 is associated with a regenerative potential of mammary epithelial cell control. Our finding also highlights the negatively regulated expression of Rspo1's partners, Lgr4 and RNF43, in the mammary gland during pregnancy. Moreover, we offer evidence that Tgf-β signalling is modified in the absence of Rspo1. Taken together, our results show an abrupt halt or delay to mammary development during pregnancy due to the loss of a further differentiated function. PMID:27611670

  7. Embryonic mammary signature subsets are activated in Brca1-/- and basal-like breast cancers

    PubMed Central

    2013-01-01

    Introduction Cancer is often suggested to result from development gone awry. Links between normal embryonic development and cancer biology have been postulated, but no defined genetic basis has been established. We recently published the first transcriptomic analysis of embryonic mammary cell populations. Embryonic mammary epithelial cells are an immature progenitor cell population, lacking differentiation markers, which is reflected in their very distinct genetic profiles when compared with those of their postnatal descendents. Methods We defined an embryonic mammary epithelial signature that incorporates the most highly expressed genes from embryonic mammary epithelium when compared with the postnatal mammary epithelial cells. We looked for activation of the embryonic mammary epithelial signature in mouse mammary tumors that formed in mice in which Brca1 had been conditionally deleted from the mammary epithelium and in human breast cancers to determine whether any genetic links exist between embryonic mammary cells and breast cancers. Results Small subsets of the embryonic mammary epithelial signature were consistently activated in mouse Brca1-/- tumors and human basal-like breast cancers, which encoded predominantly transcriptional regulators, cell-cycle, and actin cytoskeleton components. Other embryonic gene subsets were found activated in non-basal-like tumor subtypes and repressed in basal-like tumors, including regulators of neuronal differentiation, transcription, and cell biosynthesis. Several embryonic genes showed significant upregulation in estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and/or grade 3 breast cancers. Among them, the transcription factor, SOX11, a progenitor cell and lineage regulator of nonmammary cell types, is found highly expressed in some Brca1-/- mammary tumors. By using RNA interference to silence SOX11 expression in breast cancer cells, we found evidence that SOX11 regulates breast cancer cell

  8. Gene expression pattern in canine mammary osteosarcoma.

    PubMed

    Pawłowski, K M; Majewska, A; Szyszko, K; Dolka, I; Motyl, T; Król, M

    2011-01-01

    Canine mammary sarcomas are usually very aggressive and easily metastasize. Unfortunately the biology of this type of tumor is not well known because they are a very rare type of tumors. The aim of this study was to find differences in gene expression patterns in canine mammary osteosarcomas (malignant) versus osteomas (benign) using DNA microarrays. Our microarray experiment showed that 11 genes were up-regulated in osteosarcoma in comparison to osteoma whereas 36 genes were down-regulated. Among the up-regulated genes were: PDK1, EXT1, and EIF4H which are involved in AKT/PI3K and GLI/Hedgehog pathways. These genes play an important role in cell biology (cancer cell proliferation) and may be essential in osteosarcoma formation and development. Analyzing the down-regulated genes, the most interesting seemed to be HSPB8 and SEPP1. HSPB8 is a small heat shock protein that plays an important role in cell cycle regulation, apoptosis, and breast carcinogenesis. Also SEPP1 may play a role in carcinogenesis, as its down-regulation may induce oxidative stress possibly resulting in carcinogenesis. The preliminary results of the present study indicate that the up-regulation of three genes EXT1, EIF4H, and PDK1 may play an essential role in osteosarcoma formation, development and proliferation. In our opinion the cross-talk between GLI/Hedgehog and PI3K/AKT pathways may be a key factor to increase tumor proliferation and malignancy. PMID:21528706

  9. Progesterone facilitates chromosome instability (aneuploidy) in p53 null normal mammary epithelial cells

    NASA Technical Reports Server (NTRS)

    Goepfert, T. M.; McCarthy, M.; Kittrell, F. S.; Stephens, C.; Ullrich, R. L.; Brinkley, B. R.; Medina, D.

    2000-01-01

    Mammary epithelial cells from p53 null mice have been shown recently to exhibit an increased risk for tumor development. Hormonal stimulation markedly increased tumor development in p53 null mammary cells. Here we demonstrate that mammary tumors arising in p53 null mammary cells are highly aneuploid, with greater than 70% of the tumor cells containing altered chromosome number and a mean chromosome number of 56. Normal mammary cells of p53 null genotype and aged less than 14 wk do not exhibit aneuploidy in primary cell culture. Significantly, the hormone progesterone, but not estrogen, increases the incidence of aneuploidy in morphologically normal p53 null mammary epithelial cells. Such cells exhibited 40% aneuploidy and a mean chromosome number of 54. The increase in aneuploidy measured in p53 null tumor cells or hormonally stimulated normal p53 null cells was not accompanied by centrosome amplification. These results suggest that normal levels of progesterone can facilitate chromosomal instability in the absence of the tumor suppressor gene, p53. The results support the emerging hypothesis based both on human epidemiological and animal model studies that progesterone markedly enhances mammary tumorigenesis.

  10. Surface scanning: an application to mammary surgery

    NASA Astrophysics Data System (ADS)

    Rigotti, Camilla; Ferrigno, Giancarlo; Aliverti, Andrea; Pedotti, Antonio

    1998-04-01

    The possibility of mathematically describing the body surface represents a useful tool for several medical sectors, such as prosthetics or plastic surgery, and could improve diagnosis and objective evaluation of deformities and the follow-up of progressive diseases. The approach presented is based on the acquisition of a surface scanned by a laser beam. The 3D coordinates of the spot generated on the surface by the laser beam are computed by an automatic image analyzer. Using at least two different views of the subject, the 3D coordinates are obtained by stereophotogrammetry. A software package for graphic representation and extraction of linear superficial and volumetric features from the acquired surface has been developed and some preliminary results with mammary reconstruction are presented. A good mammary reconstruction after mastectomy must achieve two results. First, the reconstruction should follow the patients' wishes and second, the reconstructed breast should be as similar as possible to the contralateral one. To achieve these goals, a knowledge of breast volume, area, and shape features are essential for the surgeon. In such a context, this system could be a valuable tool in improving breast reconstructive surgery.

  11. CELL CONTACTS IN THE MOUSE MAMMARY GLAND

    PubMed Central

    Pitelka, Dorothy R.; Hamamoto, Susan T.; Duafala, Joan G.; Nemanic, Michael K.

    1973-01-01

    The nature and distribution of cell contacts have been examined in thin sections and freeze-fracture replicas of mammary gland samples from female C3H/Crgl mice at stages from birth through pregnancy, lactation, and postweaning involution. Epithelial cells of major mammary ducts at all stages examined are linked at their luminal borders by junctional complexes consisting of tight junctions, variable intermediate junctions, occasional small gap junctions, and one or more series of desmosomes. Scattered desmosomes and gap junctions link ductal epithelial and myoepithelial cells in all combinations; hemidesmosomes attach myoepithelial cells to the basal lamina. Freeze-fracture replicas confirm the erratic distribution of gap junctions and reveal a loose, irregular network of ridges comprising the continuous tight-junctional belts. Alveoli develop early in gestation and initially resemble ducts. Later, as alveoli and small ducts become actively secretory, they lose all desmosomes and most intermediate junctions, whereas tight and gap junctions persist, The tight-junctional network becomes compact and orderly, its undulating ridges oriented predominantly parallel to the luminal surface. It is suggested that these changes in junctional morphology, occurring in secretory cells around parturition, may be related to the greatly enhanced rate of movement of milk precursors and products through the lactating epithelium, or to the profound and recurrent changes in shape of secretory cells that occur in relation to myoepithelial cell contraction, or to both. PMID:4569313

  12. Three-Dimensional Cultures of Mouse Mammary Epithelial Cells

    PubMed Central

    Mroue, Rana; Bissell, Mina J.

    2013-01-01

    The mammary gland is an ideal “model organism” for studying tissue specificity and gene expression in mammals: it is one of the few organs that develop after birth and it undergoes multiple cycles of growth, differentiation and regression during the animal’s lifetime in preparation for the important function of lactation. The basic “functional differentiation” unit in the gland is the mammary acinus made up of a layer of polarized epithelial cells specialized for milk production surrounded by myoepithelial contractile cells, and the two-layered structure is surrounded by basement membrane. Much knowledge about the regulation of mammary gland development has been acquired from studying the physiology of the gland and of lactation in rodents. Culture studies, however, were hampered by the inability to maintain functional differentiation on conventional tissue culture plastic. We now know that the microenvironment, including the extracellular matrix and tissue architecture, plays a crucial role in directing functional differentiation of organs. Thus, in order for culture systems to be effective experimental models, they need to recapitulate the basic unit of differentiated function in the tissue or organ and to maintain its three-dimensional (3D) structure. Mouse mammary culture models evolved from basic monolayers of cells to an array of complex 3D systems that observe the importance of the microenvironment in dictating proper tissue function and structure. In this chapter, we focus on how 3D mouse mammary epithelial cultures have enabled investigators to gain a better understanding of the organization, development and function of the acinus, and to identify key molecular, structural, and mechanical cues important for maintaining mammary function and architecture. The accompanying chapter of Vidi et al. describes 3D models developed for human cells. Here, we describe how mouse primary epithelial cells and cell lines—essentially those we use in our

  13. Scintillation Studies of the Mouse Mammary Tumor Virus with ^125I

    NASA Astrophysics Data System (ADS)

    Yazdi, Amir; Blue, Eric; Bradley, Eric; Majewski, Stan; Mohammed, Shira; Qian, Jianguo; Saha, Margaret; Schworer, Stephen; Sutton, Jonathan; Weisenberger, Andrew; Welsh, Robert

    2007-10-01

    We have applied the techniques of scintillation imaging to studies of the mouse mammary tumor virus (MMTV). In these studies, Sodium Iodide Symporter (NIS) transfers the radioactive ^125I to the mammary glands of lactating mice and in particular to those mammaries with visible tumors. These studies have principally been carried out using pixellated scintillators coupled to position sensitive photomultiplier tubes (PSPMTs). More recently, we have initiated such studies with a monolithic slab of LaBr3 scintillator coupled to an array of PSPMTs. Several techniques of mapping and measuring the development of such tumors have been employed. These will be discussed in detail and preliminary results will be reported.

  14. Mammary candidosis in lactating women.

    PubMed

    Heinig, M J; Francis, J; Pappagianis, D

    1999-12-01

    Though perceived to be a growing problem by lactation professionals, fungal infection of the breast (mammary candidosis) is largely unstudied. Candida albicans, a commensal organism encountered frequently in the vagina and gastrointestinal tract of humans, has been reported to be responsible for both superficial (cutaneous) and localized (ductal) infection of the mammary gland in lactating women, though the latter association is not universally accepted. Severe pain is considered to be characteristic of yeast infection of the breast and may be a cause of premature weaning among lactating mothers. Given that pain is often the complaint that prompts mothers to consult lactation professionals, it is important that healthcare providers working with lactating women be knowledgeable about this disease. In this article, current research regarding yeast infection of the breast is summarized, including morphology and pathology, diagnosis, risk factors, and common treatment options.

  15. Aquaporin water channels in the mammary gland: from physiology to pathophysiology and neoplasia.

    PubMed

    Mobasheri, Ali; Barrett-Jolley, Richard

    2014-03-01

    Aquaporins are membrane proteins that play fundamental roles in water and small solute transport across epithelial and endothelial barriers. Recent studies suggest that several aquaporin proteins are present in the mammary gland. Immunohistochemical techniques have confirmed the presence of aquaporin 1 (AQP1) and AQP3 water channels in rat, mouse, bovine and human mammary glands. Studies suggest that in addition to AQP1 and AQP3 AQP4, AQP5 and AQP7 proteins are expressed in different locations in the mammary gland. Aquaporins play key roles in tumor biology and are involved in cell growth, migration and formation of ascites via increased water permeability of micro-vessels. Emerging evidence suggests that expression of these proteins is altered in mammary tumors and in breast cancer cell lines although it is not yet clear whether this is a cause or a consequence of neoplastic development. This review analyzes the expression and potential functional roles of aquaporin water channels in the mammary gland. The physiological mechanisms involved in the transport of water and small solutes across mammary endothelial and epithelial barriers are discussed in the context of milk production and lactation. This paper also reviews papers from the recent cancer literature that implicate aquaporins in mammary neoplasia.

  16. Microcalcifications in breast cancer: novel insights into the molecular mechanism and functional consequence of mammary mineralisation

    PubMed Central

    Cox, R F; Hernandez-Santana, A; Ramdass, S; McMahon, G; Harmey, J H; Morgan, M P

    2012-01-01

    Background: Mammographic microcalcifications represent one of the most reliable features of nonpalpable breast cancer yet remain largely unexplored and poorly understood. Methods: We report a novel model to investigate the in vitro mineralisation potential of a panel of mammary cell lines. Primary mammary tumours were produced by implanting tumourigenic cells into the mammary fat pads of female BALB/c mice. Results: Hydroxyapatite (HA) was deposited only by the tumourigenic cell lines, indicating mineralisation potential may be associated with cell phenotype in this in vitro model. We propose a mechanism for mammary mineralisation, which suggests that the balance between enhancers and inhibitors of physiological mineralisation are disrupted. Inhibition of alkaline phosphatase and phosphate transport prevented mineralisation, demonstrating that mineralisation is an active cell-mediated process. Hydroxyapatite was found to enhance in vitro tumour cell migration, while calcium oxalate had no effect, highlighting potential consequences of calcium deposition. In addition, HA was also deposited in primary mammary tumours produced by implanting the tumourigenic cells into the mammary fat pads of female BALB/c mice. Conclusion: This work indicates that formation of mammary HA is a cell-specific regulated process, which creates an osteomimetic niche potentially enhancing breast tumour progression. Our findings point to the cells mineralisation potential and the microenvironment regulating it, as a significant feature of breast tumour development. PMID:22233923

  17. Putting the brakes on mammary tumorigenesis: Loss of STAT1 predisposes to intraepithelial neoplasias

    PubMed Central

    Schneckenleithner, Christine; Bago-Horvath, Zsuzsanna; Dolznig, Helmut; Neugebauer, Nina; Kollmann, Karoline; Kolbe, Thomas; Decker, Thomas; Kerjaschki, Dontscho; Wagner, Kay-Uwe; Müller, Mathias; Stoiber, Dagmar; Sexl, Veronika

    2011-01-01

    Multiparous Stat1−/− mice spontaneously develop mammary tumors with increased incidence: at an average age of 12 months, 55% of the animals suffer from mammary cancer, although the histopathology is heterogeneous. We consistently observed mosaic expression or down-regulation of STAT1 protein in wild-type mammary cancer evolving in the control group. Transplantation experiments show that tumorigenesis in Stat1−/− mice is partially influenced by impaired CTL mediated tumor surveillance. Additionally, STAT1 exerts an intrinsic tumor suppressing role by controlling and blocking proliferation of the mammary epithelium. Loss of STAT1 in epithelial cells enhances cell growth in both transformed and primary cells. The increased proliferative capacity leads to the loss of structured acini formation in 3D-cultures. Analogous effects were observed when Irf1−/− epithelial cells were used. Accordingly, the rate of mammary intraepithelial neoplasias (MINs) is increased in Stat1−/− animals: MINs represent the first step towards mammary tumors. The experiments characterize STAT1/IRF1 as a key growth inhibitory and tumor suppressive signaling pathway that prevents mammary cancer formation by maintaining growth control. Furthermore, they define the loss of STAT1 as a predisposing event via enhanced MIN formation. PMID:22185785

  18. From genes to milk: genomic organization and epigenetic regulation of the mammary transcriptome.

    PubMed

    Lemay, Danielle G; Pollard, Katherine S; Martin, William F; Freeman Zadrowski, Courtneay; Hernandez, Joseph; Korf, Ian; German, J Bruce; Rijnkels, Monique

    2013-01-01

    Even in genomes lacking operons, a gene's position in the genome influences its potential for expression. The mechanisms by which adjacent genes are co-expressed are still not completely understood. Using lactation and the mammary gland as a model system, we explore the hypothesis that chromatin state contributes to the co-regulation of gene neighborhoods. The mammary gland represents a unique evolutionary model, due to its recent appearance, in the context of vertebrate genomes. An understanding of how the mammary gland is regulated to produce milk is also of biomedical and agricultural importance for human lactation and dairying. Here, we integrate epigenomic and transcriptomic data to develop a comprehensive regulatory model. Neighborhoods of mammary-expressed genes were determined using expression data derived from pregnant and lactating mice and a neighborhood scoring tool, G-NEST. Regions of open and closed chromatin were identified by ChIP-Seq of histone modifications H3K36me3, H3K4me2, and H3K27me3 in the mouse mammary gland and liver tissue during lactation. We found that neighborhoods of genes in regions of uniquely active chromatin in the lactating mammary gland, compared with liver tissue, were extremely rare. Rather, genes in most neighborhoods were suppressed during lactation as reflected in their expression levels and their location in regions of silenced chromatin. Chromatin silencing was largely shared between the liver and mammary gland during lactation, and what distinguished the mammary gland was mainly a small tissue-specific repertoire of isolated, expressed genes. These findings suggest that an advantage of the neighborhood organization is in the collective repression of groups of genes via a shared mechanism of chromatin repression. Genes essential to the mammary gland's uniqueness are isolated from neighbors, and likely have less tolerance for variation in expression, properties they share with genes responsible for an organism's survival.

  19. The type 7 serotonin receptor, 5-HT 7 , is essential in the mammary gland for regulation of mammary epithelial structure and function.

    PubMed

    Pai, Vaibhav P; Hernandez, Laura L; Stull, Malinda A; Horseman, Nelson D

    2015-01-01

    Autocrine-paracrine activity of serotonin (5-hydroxytryptamine, 5-HT) is a crucial homeostatic parameter in mammary gland development during lactation and involution. Published studies suggested that the 5-HT7 receptor type was important for mediating several effects of 5-HT in the mammary epithelium. Here, using 5-HT7 receptor-null (HT7KO) mice we attempt to understand the role of this receptor in mediating 5-HT actions within the mammary gland. We demonstrate for the first time that HT7KO dams are inefficient at sustaining their pups. Histologically, the HT7KO mammary epithelium shows a significant deviation from the normal secretory epithelium in morphological architecture, reduced secretory vesicles, and numerous multinucleated epithelial cells with atypically displaced nuclei, during lactation. Mammary epithelial cells in HT7KO dams also display an inability to transition from lactation to involution as normally seen by transition from a columnar to a squamous cell configuration, along with alveolar cell apoptosis and cell shedding. Our results show that 5-HT7 is required for multiple actions of 5-HT in the mammary glands including core functions that contribute to changes in cell shape and cell turnover, as well as specialized secretory functions. Understanding these actions may provide new interventions to improve lactation performance and treat diseases such as mastitis and breast cancer.

  20. The Type 7 Serotonin Receptor, 5-HT7, Is Essential in the Mammary Gland for Regulation of Mammary Epithelial Structure and Function

    PubMed Central

    Pai, Vaibhav P.; Hernandez, Laura L.; Stull, Malinda A.; Horseman, Nelson D.

    2015-01-01

    Autocrine-paracrine activity of serotonin (5-hydroxytryptamine, 5-HT) is a crucial homeostatic parameter in mammary gland development during lactation and involution. Published studies suggested that the 5-HT7 receptor type was important for mediating several effects of 5-HT in the mammary epithelium. Here, using 5-HT7 receptor-null (HT7KO) mice we attempt to understand the role of this receptor in mediating 5-HT actions within the mammary gland. We demonstrate for the first time that HT7KO dams are inefficient at sustaining their pups. Histologically, the HT7KO mammary epithelium shows a significant deviation from the normal secretory epithelium in morphological architecture, reduced secretory vesicles, and numerous multinucleated epithelial cells with atypically displaced nuclei, during lactation. Mammary epithelial cells in HT7KO dams also display an inability to transition from lactation to involution as normally seen by transition from a columnar to a squamous cell configuration, along with alveolar cell apoptosis and cell shedding. Our results show that 5-HT7 is required for multiple actions of 5-HT in the mammary glands including core functions that contribute to changes in cell shape and cell turnover, as well as specialized secretory functions. Understanding these actions may provide new interventions to improve lactation performance and treat diseases such as mastitis and breast cancer. PMID:25664318

  1. Phyllodes tumor of the breast: role of Axl and ST6GalNAcII in the development of mammary phyllodes tumors.

    PubMed

    Ren, Dongliang; Li, Yanyan; Gong, Yanxin; Xu, Jingchao; Miao, Xiaolong; Li, Xiangnan; Liu, Chen; Jia, Li; Zhao, Yongfu

    2014-10-01

    Phyllodes tumor exhibits an aggressive growth. The expression of many biological markers has been explored to discriminate between different grades of phyllodes tumor and to predict their behavior. The purpose of this study was to evaluate the implications of Axl and ST6GalNAcII in phyllodes tumors. Real-time PCR, Western blot, and immunohistochemical were used to analyze differential expression of ST6GalNAcII and Axl in phyllodes tumor (PT) cell lines and tissue specimens. RNAi assay, ECM invasion assay, and tumorigenicity assay were used to analyze the altered expression of ST6GalNAcII gene effects on the expression of Axl and invasive ability of phyllodes tumor cells in vitro and in vivo. Compared to benign tumors, borderline and malignant ones showed a remarkable increase in mRNA levels of Axl and ST6GalNAcII gene, and it was higher in malignant tumor cells than in borderline tumor cells. When ST6GalNAcII was silenced, compared to the control, the expression level of Axl was significantly reduced in malignant tumor cell transfectants and knockdown of ST6GalNAcII gene significantly inhibited invasive activity in malignant tumor cells. The high expression of ST6GalNAcII and Axl was significantly correlated with tumor grade and distance metastasis by immunohistochemical analysis. Axl and ST6GalNAcII expression increases with increasing tumor grade in mammary phyllodes tumors. ST6GalNAc II might be participated in the glycosylation of Axl, and this Axl glycosylation may mediate the tumorigenicity, invasion, and distant metastasis of PT cells.

  2. Estrogens in the wrong place at the wrong time: fetal BPA exposure and mammary cancer

    PubMed Central

    Paulose, Tessie; Speroni, Lucia; Sonnenschein, Carlos; Soto, Ana M

    2014-01-01

    Iatrogenic gestational exposure to diethylstilbestrol (DES) induced alterations of the genital tract and predisposed individuals to develop clear cell carcinoma of the vagina as well as breast cancer later in life. Gestational exposure of rodents to a related compound, the xenoestrogen bisphenol-A (BPA) increases the propensity to develop mammary cancer during adulthood, long after cessation of exposure. Exposure to BPA during gestation induces morphological alterations in both the stroma and the epithelium of the fetal mammary gland at 18 days of age. We postulate that the primary target of BPA is the fetal stroma, the only mammary tissue expressing estrogen receptors during fetal life. BPA would then alter the reciprocal stroma-epithelial interactions that mediate mammogenesis. In addition to this direct effect on the mammary gland, BPA is postulated to affect the hypothalamus and thus in turn affect the regulation of mammotropic hormones at puberty and beyond. PMID:25277313

  3. Consequences of epithelial or stromal TGFβ1 depletion in the mammary gland.

    PubMed

    Nguyen, David H; Martinez-Ruiz, Haydeliz; Barcellos-Hoff, Mary Helen

    2011-06-01

    Transforming growth factor β1 (TGFβ) affects stroma and epithelial composition and interactions that mediate mammary development and determine the course of cancer. The reduction of TGFβ in Tgfβ1 heterozygote mice, which are healthy and long-lived, provides an important model to dissect the contribution of TGFβ in mammary gland biology and cancer. We used both intact mice and mammary chimeras in conjunction with Tgfβ1 genetic depletion and TGFβ neutralizing antibodies to evaluate how stromal or epithelial TGFβ depletion affect mammary development and response to physiological stimuli. Our studies of radiation carcinogenesis have revealed new aspects of TGFβ biology and suggest that the paradoxical TGFβ switch from tumor suppressor to tumor promoter can be resolved by assessing distinct stromal versus epithelial actions.

  4. Estrogens in the wrong place at the wrong time: Fetal BPA exposure and mammary cancer.

    PubMed

    Paulose, Tessie; Speroni, Lucia; Sonnenschein, Carlos; Soto, Ana M

    2015-07-01

    Iatrogenic gestational exposure to diethylstilbestrol (DES) induced alterations of the genital tract and predisposed individuals to develop clear cell carcinoma of the vagina as well as breast cancer later in life. Gestational exposure of rodents to a related compound, the xenoestrogen bisphenol-A (BPA) increases the propensity to develop mammary cancer during adulthood, long after cessation of exposure. Exposure to BPA during gestation induces morphological alterations in both the stroma and the epithelium of the fetal mammary gland at 18 days of age. We postulate that the primary target of BPA is the fetal stroma, the only mammary tissue expressing estrogen receptors during fetal life. BPA would then alter the reciprocal stroma-epithelial interactions that mediate mammogenesis. In addition to this direct effect on the mammary gland, BPA is postulated to affect the hypothalamus and thus in turn affect the regulation of mammotropic hormones at puberty and beyond.

  5. Diagnostic utility of MYC amplification and anti-MYC immunohistochemistry in atypical vascular lesions, primary or radiation-induced mammary angiosarcomas, and primary angiosarcomas of other sites.

    PubMed

    Ginter, Paula S; Mosquera, Juan Miguel; MacDonald, Theresa Y; D'Alfonso, Timothy M; Rubin, Mark A; Shin, Sandra J

    2014-04-01

    Breast cancer patients who receive radiation therapy or develop chronic lymphedema following axillary dissection can develop secondary mammary angiosarcomas (ASs) and, additionally, atypical vascular lesions (AVLs) in the former group. Recently, MYC amplification by fluorescence in situ hybridization (FISH) has been identified in secondary mammary AS but not in AVL and most primary mammary AS as well as AS of other sites. We studied MYC amplification and MYC protein expression in 7 radiation-induced AVLs, 9 secondary mammary ASs, 17 primary mammary ASs, and 20 primary ASs of other sites by FISH analysis and immunohistochemistry. All 9 secondary mammary ASs showed gene amplification and protein expression, whereas neither was found in any of 7 AVLs. No MYC amplification or protein expression was identified in any of the 17 primary mammary ASs. Among primary ASs of other sites, 1 cardiac AS and 1 skin AS showed gene amplification and protein expression. The remaining 18 did not show amplification (90%), but some demonstrated protein expression (39%). We conclude that MYC amplification by FISH is present in secondary mammary AS but not in AVL. We also found MYC amplification in 1 primary skin AS and 1 primary cardiac AS. There was 100% concordance between MYC amplification and protein expression in all AVL, primary mammary AS, and secondary mammary AS, whereas only 65% concordance was found in AS of other sites. MYC protein expression in AS can be helpful in certain diagnostic scenarios in the breast but not in other sites.

  6. Chemoprevention of Radiation Induced Rat Mammary Neoplasms

    NASA Technical Reports Server (NTRS)

    Huso, David L.

    1999-01-01

    Radiations encountered in space include protons and heavy ions such as iron as well as their secondaries. The relative biological effect (RBE) of these ions is not known, particularly at the doses and dose-rates expected for planetary missions. Neutrons, are not particularly relevant to space travel, but have been found experimentally to have an increase in their RBE with decreasing dose. If a similar trend of increasing RBE with decreasing dose is present for heavy ions and protons during irradiation in space, the small doses received during space travel could potentially have substantial carcinogenic risk. Clearly more investigation of the effects of heavy ions and protons is needed before accurate risk assessment for prolonged travel in space can be done. One means to mitigate the increased risk of cancer due to radiation exposure in space is by developing effective countermeasures that can reduce the incidence of tumor development. Tamoxifen has recently been shown to be an effective chemopreventive agent in both animal models and humans for the prevention of mammary tumors. Tamoxifen is a unique drug, with a highly specific mechanism of action affecting a specific radiation-sensitive population of epithelial cells in the mammary gland. In human studies, the annual incidence of a primary tumor in the contralateral breast of women with previous breast cancer is about 8 per 1000, making them an exceedingly high-risk group for the development of breast cancer. In this high risk group, treated with tamoxifen, daily, for 2 years, the incidence of a new primary tumor in the contralateral breast was approximately one third of that noted in the non-tamoxifen treatment group. Tamoxifen antagonizes the action of estrogen by competing for the nuclear receptor complex thereby altering the association of the receptor complex and nuclear binding sites. Its effects in reducing the development of breast cancer could be accomplished by controlling clinically undetectable

  7. In situ force mapping of mammary gland transformation

    PubMed Central

    Lopez, Jose I.; Kang, Inkyung; You, Weon-Kyoo; McDonald, Donald M.; Weaver, Valerie M.

    2013-01-01

    Tumor progression is characterized by an incremental stiffening of the tissue. The importance of tissue rigidity to cancer is appreciated, yet the contribution of specific tissue elements to tumor stiffening and their physiological significance remains unclear. We performed high-resolution atomic force microscopy indentation in live and snap-frozen fluorescently labeled mammary tissues to explore the origin of the tissue stiffening associated with mammary tumor development in PyMT mice. The tumor epithelium, the tumor-associated vasculature and the extracellular matrix all contributed to mammary gland stiffening as it transitioned from normal to invasive carcinoma. Consistent with the concept that extracellular matrix stiffness modifies cell tension, we found that isolated transformed mammary epithelial cells were intrinsically stiffer than their normal counterparts but that the malignant epithelium in situ was far stiffer than isolated breast tumor cells. Moreover, using an in situ vitrification approach, we determined that the extracellular matrix adjacent to the epithelium progressively stiffened as tissue evolved from normal through benign to an invasive state. Importantly, we also noted that there was significant mechanical heterogeneity within the transformed tissue both in the epithelium and the tumor-associated neovasculature. The vascular bed within the tumor core was substantially stiffer than the large patent vessels at the invasive front that are surrounded by the stiffest extracellular matrix. These findings clarify the contribution of individual mammary gland tissue elements to the altered biomechanical landscape of cancerous tissues and emphasize the importance of studying cancer cell evolution under conditions that preserve native interactions. PMID:21842067

  8. Mammary gland tumor formation in transgenic mice overexpressing stromelysin-1

    SciTech Connect

    Sympson, Carolyn J; Bissell, Mina J; Werb, Zena

    1995-06-01

    An intact basement membrane (BM) is essential for the proper function, differentiation and morphology of many epithelial cells. The disruption or loss of this BM occurs during normal development as well as in the disease state. To examine the importance of BM during mammary gland development in vivo, we generated transgenic mice that inappropriately express autoactivating isoforms of the matrix metalloproteinase stromelysin-1. The mammary glands from these mice are both functionally and morphologically altered throughout development. We have now documented a dramatic incidence of breast tumors in several independent lines of these mice. These data suggest that overexpression of stromelysin-1 and disruption of the BM may be a key step in the multi-step process of breast cancer.

  9. Short communication: Expression of T-box 2 and 3 in the bovine mammary gland.

    PubMed

    Hoffman, M L; McFadden, K K; Hoagland, T A; Kazmer, G W; Govoni, K E

    2014-07-01

    To increase our understanding of the mechanisms by which growth hormone (GH) and insulin-like growth factor (IGF)-I influence bovine mammary gland development, the potential roles of T-box2 (TBX2) and T-box3 (TBX3) were investigated. Although no information regarding expression of either transcription factor in the bovine mammary gland exists, it is known that TBX3 and its closely related family member, TBX2, are required for mammary gland development in humans and mice. Additionally, TBX3 mutations in humans and mice lead to ulnar mammary syndrome. Evidence is present in bone that TBX3 is required for proliferation and its expression is regulated by GH, an important regulator of mammary gland development and milk production. We hypothesized that TBX2 and TBX3 are expressed in the bovine mammary gland and that GH, IGF-I, or both increase TBX2 and TBX3 expression in bovine mammary epithelial cells (MEC). Bovine mammary gland tissue, MAC-T cells, primary MEC, and fibroblasts were obtained and TBX2 and TBX3 expression was determined by real-time reverse transcription PCR. In addition, TBX2 and TBX3 expression was examined in cells treated with 100 or 500 ng/mL of GH or 100 or 200 ng/mL of IGF-I for 24 or 48 h. Both TBX2 and TBX3 were expressed in bovine mammary tissue. Surprisingly, expression of TBX2 was only detected in mammary fibroblast cells, whereas TBX3 was expressed in all 3 cell types. Growth hormone did not alter TBX3 expression in MAC-T cells or MEC. However, IGF-I increased TBX3 expression in MAC-T, but not in primary MEC. We did not observe a change in TBX2 or TBX3 expression in fibroblasts treated with GH and IGF. Therefore, we concluded that (1) TBX2 and TBX3 are expressed in bovine mammary gland, (2) their expression is cell-type specific, and (3) IGF-I stimulates TBX3 expression in MAC-T cells. PMID:24767885

  10. 9 CFR 310.17 - Inspection of mammary glands.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Inspection of mammary glands. 310.17... INSPECTION AND CERTIFICATION POST-MORTEM INSPECTION § 310.17 Inspection of mammary glands. (a) Lactating mammary glands and diseased mammary glands of cattle, sheep, swine, and goats shall be removed...

  11. The interplay of matrix metalloproteinases, morphogens and growth factors is necessary for branching of mammary epithelial cells

    SciTech Connect

    Simian, M.; Harail, Y.; Navre, M.; Werb, Z.; Lochter, A.; Bissell, M.J.

    2002-03-06

    The mammary gland develops its adult form by a process referred to as branching morphogenesis. Many factors have been reported to affect this process. We have used cultured primary mammary epithelial organoids and mammary epithelial cell lines in three-dimensional collagen gels to elucidate which growth factors, matrix metalloproteinases (MMPs) and mammary morphogens interact in branching morphogenesis. Branching stimulated by stromal fibroblasts, epidermal growth factor, fibroblast growth factor 7, fibroblast growth factor 2 and hepatocyte growth factor was strongly reduced by inhibitors of MMPs, indicating the requirement of MMPs for three-dimensional growth involved in morphogenesis. Recombinant stromelysin 1/MMP-3 alone was sufficient to drive branching in the absence of growth factors in the organoids. Plasmin also stimulated branching; however, plasmin-dependent branching was abolished by both inhibitors of plasmin and MMPs, suggesting that plasmin activates MMPs. To differentiate between signals for proliferation and morphogenesis, we used a cloned mammary epithelial cell line that lacks epimorphin, an essential mammary morphogen. Both epimorphin and MMPs were required for morphogenesis, but neither was required for epithelial cell proliferation. These results provide direct evidence for a critical role of MMPs in branching in mammary epithelium and suggest that, in addition to epimorphin, MMP activity is a minimum requirement for branching morphogenesis in the mammary gland.

  12. Metabotropic glutamate receptor 1 disrupts mammary acinar architecture and initiates malignant transformation of mammary epithelial cells.

    PubMed

    Teh, Jessica L F; Shah, Raj; La Cava, Stephanie; Dolfi, Sonia C; Mehta, Madhura S; Kongara, Sameera; Price, Sandy; Ganesan, Shridar; Reuhl, Kenneth R; Hirshfield, Kim M; Karantza, Vassiliki; Chen, Suzie

    2015-05-01

    Metabotropic glutamate receptor 1 (mGluR1/Grm1) is a member of the G-protein-coupled receptor superfamily, which was once thought to only participate in synaptic transmission and neuronal excitability, but has more recently been implicated in non-neuronal tissue functions. We previously described the oncogenic properties of Grm1 in cultured melanocytes in vitro and in spontaneous melanoma development with 100 % penetrance in vivo. Aberrant mGluR1 expression was detected in 60-80 % of human melanoma cell lines and biopsy samples. As most human cancers are of epithelial origin, we utilized immortalized mouse mammary epithelial cells (iMMECs) as a model system to study the transformative properties of Grm1. We introduced Grm1 into iMMECs and isolated several stable mGluR1-expressing clones. Phenotypic alterations in mammary acinar architecture were assessed using three-dimensional morphogenesis assays. We found that mGluR1-expressing iMMECs exhibited delayed lumen formation in association with decreased central acinar cell death, disrupted cell polarity, and a dramatic increase in the activation of the mitogen-activated protein kinase pathway. Orthotopic implantation of mGluR1-expressing iMMEC clones into mammary fat pads of immunodeficient nude mice resulted in mammary tumor formation in vivo. Persistent mGluR1 expression was required for the maintenance of the tumorigenic phenotypes in vitro and in vivo, as demonstrated by an inducible Grm1-silencing RNA system. Furthermore, mGluR1 was found be expressed in human breast cancer cell lines and breast tumor biopsies. Elevated levels of extracellular glutamate were observed in mGluR1-expressing breast cancer cell lines and concurrent treatment of MCF7 xenografts with glutamate release inhibitor, riluzole, and an AKT inhibitor led to suppression of tumor progression. Our results are likely relevant to human breast cancer, highlighting a putative role of mGluR1 in the pathophysiology of breast cancer and the potential

  13. Characterization of microRNA profile in mammary tissue of dairy and beef breed heifers.

    PubMed

    Wicik, Z; Gajewska, M; Majewska, A; Walkiewicz, D; Osińska, E; Motyl, T

    2016-02-01

    MicroRNAs (miRNAs) are small non-coding RNAs that participate in the regulation of gene expression. Their role during mammary gland development is still largely unknown. In this study, we performed a microarray analysis to identify miRNAs associated with high mammogenic potential of the bovine mammary gland. We identified 54 significantly differentially expressed miRNAs between the mammary tissue of dairy (Holstein-Friesian, HF) and beef (Limousin, LM) postpubertal heifers. Fifty-two miRNAs had higher expression in the mammary tissue of LM heifers. The expression of the top candidate miRNAs (bta-miR-10b, bta-miR-29b, bta-miR-101, bta-miR-375, bta-miR-2285t, bta-miR-146b, bta-let7b, bta-miR-107, bta-miR-1434-3p) identified in the microarray experiment was additionally evaluated by qPCR. Enrichment analyses for targeted genes revealed that the major differences between miRNA expression in the mammary gland of HF versus LM were associated with the regulation of signalling pathways that are crucial for mammary gland development, such as TGF-beta, insulin, WNT and inflammatory pathways. Moreover, a number of genes potentially targeted by significantly differentially expressed miRNAs were associated with the activity of mammary stem cells. These data indicate that the high developmental potential of the mammary gland in dairy cattle, leading to high milk productivity, depends also on a specific miRNA expression pattern. PMID:26060050

  14. Protein tyrosine kinase 6 promotes ERBB2-induced mammary gland tumorigenesis in the mouse.

    PubMed

    Peng, M; Ball-Kell, S M; Tyner, A L

    2015-01-01

    Protein tyrosine kinase 6 (PTK6) expression, activation, and amplification of the PTK6 gene have been reported in ERBB2/HER2-positive mammary gland cancers. To explore contributions of PTK6 to mammary gland tumorigenesis promoted by activated ERBB2, we crossed Ptk6-/- mice with the mouse mammary tumor virus-ERBB2 transgenic mouse line expressing activated ERBB2 and characterized tumor development and progression. ERBB2-induced tumorigenesis was significantly delayed and diminished in mice lacking PTK6. PTK6 expression was induced in the mammary glands of ERBB2 transgenic mice before tumor development and correlated with activation of signal transducer and activator of transcription 3 (STAT3) and increased proliferation. Disruption of PTK6 impaired STAT3 activation and proliferation. Phosphorylation of the PTK6 substrates focal adhesion kinase (FAK) and breast cancer anti-estrogen resistance 1 (BCAR1; p130CAS) was decreased in Ptk6-/- mammary gland tumors. Reduced numbers of metastases were detected in the lungs of Ptk6-/- mice expressing activated ERBB2, compared with wild-type ERBB2 transgenic mice. PTK6 activation was detected at the edges of ERBB2-positive tumors. These data support roles for PTK6 in both ERBB2-induced mammary gland tumor initiation and metastasis, and identify STAT3, FAK, and BCAR1 as physiologically relevant PTK6 substrates in breast cancer. Including PTK6 inhibitors as part of a treatment regimen could have distinct benefits in ERBB2/HER2-positive breast cancers.

  15. Radiogenic neoplasia in thyroid and mammary clonogens

    SciTech Connect

    Clifton, K.H.

    1991-05-31

    We have developed rat thyroid and mammary clonogen transplantation systems for the study of radiogenic cancer induction at the target cell level in vivo. The epithelial cell populations of both glands contain small subpopulations of cells which are capable of giving rise to monoclonal glandular structures when transplanted and stimulated with appropriate hormones. During the end of the last grant year and the first half of the current grant year, we have completed analyses and summarized for publication: investigations on the relationship between grafted thyroid cell number and the rapidity and degree of reestablishment of the thyroid-hypothalamicpituitary axis in thyroidectomized rats maintained on a normal diet or an iodine deficient diet; studies of the persistence of, and the differentiation potential and functional characteristics of, the TSH- (thyrotropin-) responsive sub-population of clonogens during goitrogenesis, the plateau-phase of goiter growth, and goiter involution; studies of changes in the size of the clonogen sub-population during goitrogenesis, goiter involution and the response to goitrogen rechallenge; and the results of the large carcinogenesis experiment on the nature of the grafted thyroid cell number-dependent suppression of promotion/progression to neoplasia in grafts of radiation-initiated thyroid cells. We are testing new techniques for the culture, cytofluorescent analysis and characterization mammary epithelial cells and of clonogens in a parallel project, and plan to apply similar technology to the thyroid epithelial cells and clonogen population. Data from these studies will be used in the design of future carcinogenesis experiments on neoplastic initiation by high and low LET radiations and on cells interactions during the neoplastic process.

  16. Mammary and extramammary Paget's disease.

    PubMed

    Lopes Filho, Lauro Lourival; Lopes, Ione Maria Ribeiro Soares; Lopes, Lauro Rodolpho Soares; Enokihara, Milvia M S S; Michalany, Alexandre Osores; Matsunaga, Nobuo

    2015-01-01

    Paget's disease, described by Sir James Paget in 1874, is classified as mammary and extramammary. The mammary type is rare and often associated with intraductal cancer (93-100% of cases). It is more prevalent in postmenopausal women and it appears as an eczematoid, erythematous, moist or crusted lesion, with or without fine scaling, infiltration and inversion of the nipple. It must be distinguished from erosive adenomatosis of the nipple, cutaneous extension of breast carcinoma, psoriasis, atopic dermatitis, contact dermatitis, chronic eczema, lactiferous ducts ectasia, Bowen's disease, basal cell carcinoma, melanoma and intraductal papilloma. Diagnosis is histological and prognosis and treatment depend on the type of underlying breast cancer. Extramammary Paget's disease is considered an adenocarcinoma originating from the skin or skin appendages in areas with apocrine glands. The primary location is the vulvar area, followed by the perianal region, scrotum, penis and axillae. It starts as an erythematous plaque of indolent growth, with well-defined edges, fine scaling, excoriations, exulcerations and lichenification. In most cases it is not associated with cancer, although there are publications linking it to tumors of the vulva, vagina, cervix and corpus uteri, bladder, ovary, gallbladder, liver, breast, colon and rectum. Differential diagnoses are candidiasis, psoriasis and chronic lichen simplex. Histopathology confirms the diagnosis. Before treatment begins, associated malignancies should be investigated. Surgical excision and micrographic surgery are the best treatment options, although recurrences are frequent. PMID:25830993

  17. Chronic social isolation is associated with metabolic gene expression changes specific to mammary adipose tissue.

    PubMed

    Volden, Paul A; Wonder, Erin L; Skor, Maxwell N; Carmean, Christopher M; Patel, Feenalie N; Ye, Honggang; Kocherginsky, Masha; McClintock, Martha K; Brady, Matthew J; Conzen, Suzanne D

    2013-07-01

    Chronic social isolation is linked to increased mammary tumor growth in rodent models of breast cancer. In the C3(1)/SV40 T-antigen FVB/N (TAg) mouse model of "triple-negative" breast cancer, the heightened stress response elicited by social isolation has been associated with increased expression of metabolic genes in the mammary gland before invasive tumors develop (i.e., during the in situ carcinoma stage). To further understand the mechanisms underlying how accelerated mammary tumor growth is associated with social isolation, we separated the mammary gland adipose tissue from adjacent ductal epithelial cells and analyzed individual cell types for changes in metabolic gene expression. Specifically, increased expression of the key metabolic genes Acaca, Hk2, and Acly was found in the adipocyte, rather than the epithelial fraction. Surprisingly, metabolic gene expression was not significantly increased in visceral adipose depots of socially isolated female mice. As expected, increased metabolic gene expression in the mammary adipocytes of socially isolated mice coincided with increased glucose metabolism, lipid synthesis, and leptin secretion from this adipose depot. Furthermore, application of media that had been cultured with isolated mouse mammary adipose tissue (conditioned media) resulted in increased proliferation of mammary cancer cells relative to group-housed-conditioned media. These results suggest that exposure to a chronic stressor (social isolation) results in specific metabolic reprogramming in mammary gland adipocytes that in turn contributes to increased proliferation of adjacent preinvasive malignant epithelial cells. Metabolites and/or tumor growth-promoting proteins secreted from adipose tissue could identify biomarkers and/or targets for preventive intervention in breast cancer.

  18. Protein tyrosine kinase 6 regulates mammary gland tumorigenesis in mouse models

    PubMed Central

    Peng, M; Ball-Kell, S M; Franks, R R; Xie, H; Tyner, A L

    2013-01-01

    Protein tyrosine kinase 6 (PTK6, also called BRK) is an intracellular tyrosine kinase expressed in the majority of human breast tumors and breast cancer cell lines, but its expression has not been reported in normal mammary gland. To study functions of PTK6 in vivo, we generated and characterized several transgenic mouse lines with expression of human PTK6 under control of the mouse mammary tumor virus (MMTV) long terminal repeat. Ectopic active PTK6 was detected in luminal epithelial cells of mature transgenic mammary glands. Lines expressing the MMTV-PTK6 transgene exhibited more than a two-fold increase in mammary gland tumor formation compared with nontransgenic control animals. PTK6 activates signal transducer and activator of transcription 3 (STAT3), and active STAT3 was detected in PTK6-positive mammary gland epithelial cells. Endogenous mouse PTK6 was not detected in the normal mouse mammary gland, but it was induced in mouse mammary gland tumors of different origin, including spontaneous tumors that developed in control mice, and tumors that formed in PTK6, H-Ras, ERBB2 and PyMT transgenic models. MMTV-PTK6 and MMTV-ERBB2 transgenic mice were crossed to explore crosstalk between PTK6 and ERBB2 signaling in vivo. We found no significant increase in tumor incidence, size or metastasis in ERBB2/PTK6 double transgenic mice. Although we detected increased proliferation in ERBB2/PTK6 double transgenic tumors, an increase in apoptosis was also observed. MMTV-PTK6 clearly promotes mammary gland tumorigenesis in vivo, but its impact may be underrepresented in our transgenic models because of induction of endogenous PTK6 expression. PMID:24323291

  19. Progesterone receptors in normal mammary gland: receptor modulations in relation to differentiation

    PubMed Central

    1980-01-01

    The biological basis for the observed modulation in cytoplasmic progesterone receptors (PgR) of normal mammary gland occurring during mammary development was investigated. Specifically, the relative roles of hormones vs. differentiation on (a) the decrease in PgR concentration during pregnancy and lactation and (b) the loss of mammary responsiveness to estrogen during lactation were examined. PgR were measured using the synthetic progestin, R5020, as the ligand. The hormones estrogen and progesterone were tested in vivo for their effect of PgR concentration. Mammary gland differentiation was assessed morphologically and by measuring enzymatically active alpha- lactalbumin. These studies show that there is a stepwise decrease in PgR that occurs in two stages. The first decrease is completed by day 12 of pregnancy and the second decrease occurs only after parturition. There appears to be a hormonal basis for the first decrease and it appears to be caused by the negative effect of progesterone on estrogen- mediated increase in PgR. In direct contrast, the absence of PgR during lactation and the mammary tissue insensitivity to estrogenic stimulation of PgR were not related to the hormonal milieu of lactation but were directly related to the secretory state of the mammary gland and lactation per se. PMID:7410476

  20. Form and function: how estrogen and progesterone regulate the mammary epithelial hierarchy.

    PubMed

    Arendt, Lisa M; Kuperwasser, Charlotte

    2015-06-01

    The mammary gland undergoes dramatic post-natal growth beginning at puberty, followed by full development occurring during pregnancy and lactation. Following lactation, the alveoli undergo apoptosis, and the mammary gland reverses back to resemble the nonparous gland. This process of growth and regression occurs for multiple pregnancies, suggesting the presence of a hierarchy of stem and progenitor cells that are able to regenerate specialized populations of mammary epithelial cells. Expansion of epithelial cell populations in the mammary gland is regulated by ovarian steroids, in particular estrogen acting through its receptor estrogen receptor alpha (ERα) and progesterone signaling through progesterone receptor (PR). A diverse number of stem and progenitor cells have been identified based on expression of cell surface markers and functional assays. Here we review the current understanding of how estrogen and progesterone act together and separately to regulate stem and progenitor cells within the human and mouse mammary tissues. Better understanding of the hierarchal organization of epithelial cell populations in the mammary gland and how the hormonal milieu affects its regulation may provide important insights into the origins of different subtypes of breast cancer.

  1. /sup 20/neon ion- and x-ray-induced mammary carcinogenesis in female rats

    SciTech Connect

    Shellabarger, C.J.; Baum, J.W.; Holtzman, S.; Stone, J.P.

    1983-01-01

    One of the proposed uses of heavy ion irradiation is to image lesions of the human female breast. The rat model system was chosen to assess the carcinogenic potential of heavy ion irradiation in the belief that data obtained from rat studies would have a qualitatively predictive value for the human female. Accordingly, female rats were exposed to /sup 20/Ne ions at the BEVALAC and studied for the development of mammary neoplasia for 312 +- 2 days at Brookhaven along with rats exposed concurrently to x-irradiation or to no irradiation. As the dose of either type of radiation was increased the percent of rats with mammary adenocarcinomas, and the percent of rats with mammary fibroadenomas, tended to increase. At a prevalence of 20%, the RBE for /sup 20/Neon ions for mammary adenocarcinomas was estimated to be larger than 5 and for mammary fibroadenomas the RBE was estimated to be less than 2. No conclusion was reached concerning whether or not the RBE might vary with dose. We suggest that /sup 20/Ne ions do have a carcinogenic potential for rat mammary tissue and that this carcinogenic potential is likely to be greater than for x-irradiation. (DT)

  2. Biological and genetic properties of the p53 null preneoplastic mammary epithelium

    NASA Technical Reports Server (NTRS)

    Medina, Daniel; Kittrell, Frances S.; Shepard, Anne; Stephens, L. Clifton; Jiang, Cheng; Lu, Junxuan; Allred, D. Craig; McCarthy, Maureen; Ullrich, Robert L.

    2002-01-01

    The absence of the tumor suppressor gene p53 confers an increased tumorigenic risk for mammary epithelial cells. In this report, we describe the biological and genetic properties of the p53 null preneoplastic mouse mammary epithelium in a p53 wild-type environment. Mammary epithelium from p53 null mice was transplanted serially into the cleared mammary fat pads of p53 wild-type BALB/c female to develop stable outgrowth lines. The outgrowth lines were transplanted for 10 generations. The outgrowths were ductal in morphology and progressed through ductal hyperplasia and ductal carcinoma in situ before invasive cancer. The preneoplastic outgrowth lines were immortal and exhibited activated telomerase activity. They are estrogen and progesterone receptor-positive, and aneuploid, and had various levels of tumorigenic potential. The biological and genetic properties of these lines are distinct from those found in most hyperplastic alveolar outgrowth lines, the form of mammary preneoplasia occurring in most traditional models of murine mammary tumorigenesis. These results indicate that the preneoplastic cell populations found in this genetically engineered model are similar in biological properties to a subset of precurser lesions found in human breast cancer and provide a unique model to identify secondary events critical for tumorigenicity and invasiveness.

  3. Hedgehog signaling in the normal and neoplastic mammary gland.

    PubMed

    Visbal, Adriana P; Lewis, Michael T

    2010-09-01

    The hedgehog signal transduction network is a critical regulator of metazoan development. Inappropriate activation of this network is implicated in several different cancers, including breast. Genetic evidence in mice as well as molecular biological studies in human cells clearly indicate that activated signaling can lead to mammary hyperplasia and, in some cases, tumor formation. However, the exact role(s) activated hedgehog signaling plays in the development or progression of breast cancer also remain unclear. In this review, we have discussed recent data regarding the mechanism(s) by which the hedgehog network may signal in the mammary gland, as well as the data implicating activated signaling as a contributing factor to breast cancer development. Finally, we provide a brief update on the available hedgehog signaling inhibitors with respect to ongoing clinical trials, some of which will include locally advanced or metastatic breast cancers. Given the growing intensity with which the hedgehog signaling network is being studied in the normal and neoplastic mammary gland, a more complete understanding of this network should allow more effective targeting of its activities in breast cancer treatment or prevention.

  4. Significance of rat mammary tumors for human risk assessment.

    PubMed

    Russo, Jose

    2015-02-01

    We have previously indicated that the ideal animal tumor model should mimic the human disease. This means that the investigator should be able to ascertain the influence of host factors on the initiation of tumorigenesis, mimic the susceptibility of tumor response based on age and reproductive history, and determine the response of the tumors induced to chemotherapy. The utilization of experimental models of mammary carcinogenesis in risk assessment requires that the influence of ovarian, pituitary, and placental hormones, among others, as well as overall reproductive events are taken into consideration, since they are important modifiers of the susceptibility of the organ to neoplastic development. Several species, such as rodents, dogs, cats, and monkeys, have been evaluated for these purposes; however, none of them fulfills all the criteria specified previously. Rodents, however, are the most widely used models; therefore, this work will concentrate on discussing the rat rodent model of mammary carcinogenesis. PMID:25714400

  5. Gordon Research Conference on Mammary Gland Biology

    SciTech Connect

    Not Available

    1989-01-01

    The 1989 conference was the tenth in the series of biennial Gordon Research Conferences on Mammary Gland Biology. Traditionally this conference brings together scientists from diverse backgrounds and experience but with a common interest in the biology of the mammary gland. Investigators from agricultural and medical schools, biochemists, cell and molecular biologists, endocrinologists, immunologists, and representatives from the emerging biotechnology industries met to discuss current concepts and results on the function and regulation of the normal and neoplastic mammary gland in a variety of species. Of the participants, approximately three-fourths were engaged in studying the normal mammary gland function, whereas the other quarter were engaged in studying the neoplastic gland. The interactions between scientists, clinicians, veterinarians examining both normal and neoplastic cell function serves to foster the multi-disciplinary goals of the conference and has stimulated many cooperative projects among participants in previous years.

  6. Genetic component in rat mammary carcinogenesis

    SciTech Connect

    Vogel, H.J. Jr.; Turner, J.E.

    1982-02-01

    Five genetically defined strains of female rats were exposed to whole-body radiation with a single dose of 50 rad of fission neutrons. After 1 year 56% of the Long-Evans and Sprague-Dawely strains showed at least one mammary tumor; 25-29% of the Buffalo and Fischer-344 strains and only 5% of the Wistar-Lewis strain and palpable mammary tumors. Only one tumor was found among 73 unirradiated controls during the 1-year observation period. Approximately two-thirds of 50 mammary analyzed pathologically were adenofibromas and fibroadenomas; one-third were adenocarcinomas. The Kaplan-Meier method of life table analysis was used to deal with the problem of intercurrent mortality. A genetic factor seems evident in rat mammary tumorigenesis following exposure to fission neutrons.

  7. Mammary Gland Evaluation in Juvenile Toxicity Studies: Temporal Developmental Patterns in the Male and Female Harlan Sprague-Dawley Rat.

    PubMed

    Filgo, Adam J; Foley, Julie F; Puvanesarajah, Samantha; Borde, Aditi R; Midkiff, Bentley R; Reed, Casey E; Chappell, Vesna A; Alexander, Lydia B; Borde, Pretish R; Troester, Melissa A; Bouknight, Schantel A Hayes; Fenton, Suzanne E

    2016-10-01

    There are currently no reports describing mammary gland development in the Harlan Sprague-Dawley (HSD) rat, the current strain of choice for National Toxicology Program (NTP) testing. Our goals were to empower the NTP, contract labs, and other researchers in understanding and interpreting chemical effects in this rat strain. To delineate similarities/differences between the female and male mammary gland, data were compiled starting on embryonic day 15.5 through postnatal day 70. Mammary gland whole mounts, histology sections, and immunohistochemically stained tissues for estrogen, progesterone, and androgen receptors were evaluated in both sexes; qualitative and quantitative differences are highlighted using a comprehensive visual timeline. Research on endocrine disrupting chemicals in animal models has highlighted chemically induced mammary gland anomalies that may potentially impact human health. In order to investigate these effects within the HSD strain, 2,3,7,8-tetrachlorodibenzo-p-dioxin, diethylstilbestrol, or vehicle control was gavage dosed on gestation day 15 and 18 to demonstrate delayed, accelerated, and control mammary gland growth in offspring, respectively. We provide illustrations of normal and chemically altered mammary gland development in HSD male and female rats to help inform researchers unfamiliar with the tissue and may facilitate enhanced evaluation of both male and female mammary glands in juvenile toxicity studies. PMID:27613106

  8. Mammary Gland Evaluation in Juvenile Toxicity Studies: Temporal Developmental Patterns in the Male and Female Harlan Sprague-Dawley Rat.

    PubMed

    Filgo, Adam J; Foley, Julie F; Puvanesarajah, Samantha; Borde, Aditi R; Midkiff, Bentley R; Reed, Casey E; Chappell, Vesna A; Alexander, Lydia B; Borde, Pretish R; Troester, Melissa A; Bouknight, Schantel A Hayes; Fenton, Suzanne E

    2016-10-01

    There are currently no reports describing mammary gland development in the Harlan Sprague-Dawley (HSD) rat, the current strain of choice for National Toxicology Program (NTP) testing. Our goals were to empower the NTP, contract labs, and other researchers in understanding and interpreting chemical effects in this rat strain. To delineate similarities/differences between the female and male mammary gland, data were compiled starting on embryonic day 15.5 through postnatal day 70. Mammary gland whole mounts, histology sections, and immunohistochemically stained tissues for estrogen, progesterone, and androgen receptors were evaluated in both sexes; qualitative and quantitative differences are highlighted using a comprehensive visual timeline. Research on endocrine disrupting chemicals in animal models has highlighted chemically induced mammary gland anomalies that may potentially impact human health. In order to investigate these effects within the HSD strain, 2,3,7,8-tetrachlorodibenzo-p-dioxin, diethylstilbestrol, or vehicle control was gavage dosed on gestation day 15 and 18 to demonstrate delayed, accelerated, and control mammary gland growth in offspring, respectively. We provide illustrations of normal and chemically altered mammary gland development in HSD male and female rats to help inform researchers unfamiliar with the tissue and may facilitate enhanced evaluation of both male and female mammary glands in juvenile toxicity studies.

  9. Mammary Adipose Tissue-Derived Lysophospholipids Promote Estrogen Receptor-Negative Mammary Epithelial Cell Proliferation.

    PubMed

    Volden, Paul A; Skor, Maxwell N; Johnson, Marianna B; Singh, Puneet; Patel, Feenalie N; McClintock, Martha K; Brady, Matthew J; Conzen, Suzanne D

    2016-05-01

    Lysophosphatidic acid (LPA), acting in an autocrine or paracrine fashion through G protein-coupled receptors, has been implicated in many physiologic and pathologic processes, including cancer. LPA is converted from lysophosphatidylcholine (LPC) by the secreted phospholipase autotaxin (ATX). Although various cell types can produce ATX, adipocyte-derived ATX is believed to be the major source of circulating ATX and also to be the major regulator of plasma LPA levels. In addition to ATX, adipocytes secrete numerous other factors (adipokines); although several adipokines have been implicated in breast cancer biology, the contribution of mammary adipose tissue-derived LPC/ATX/LPA (LPA axis) signaling to breast cancer is poorly understood. Using murine mammary fat-conditioned medium, we investigated the contribution of LPA signaling to mammary epithelial cancer cell biology and identified LPA signaling as a significant contributor to the oncogenic effects of the mammary adipose tissue secretome. To interrogate the role of mammary fat in the LPA axis during breast cancer progression, we exposed mammary adipose tissue to secreted factors from estrogen receptor-negative mammary epithelial cell lines and monitored changes in the mammary fat pad LPA axis. Our data indicate that bidirectional interactions between mammary cancer cells and mammary adipocytes alter the local LPA axis and increase ATX expression in the mammary fat pad during breast cancer progression. Thus, the LPC/ATX/LPA axis may be a useful target for prevention in patients at risk of ER-negative breast cancer. Cancer Prev Res; 9(5); 367-78. ©2016 AACR. PMID:26862086

  10. Hoxc8 initiates an ectopic mammary program by regulating Fgf10 and Tbx3 expression and Wnt/β-catenin signaling

    PubMed Central

    Carroll, Lara S.; Capecchi, Mario R.

    2015-01-01

    The role of Hox genes in the formation of cutaneous accessory organs such as hair follicles and mammary glands has proved elusive, a likely consequence of overlapping function and expression among various homeobox factors. Lineage and immunohistochemical analysis of Hoxc8 in mice revealed that this midthoracic Hox gene has transient but strong regional expression in ventrolateral surface ectoderm at E10.5, much earlier than previously reported. Targeted mice were generated to conditionally misexpress Hoxc8 from the Rosa locus using select Cre drivers, which significantly expanded the domain of thoracic identity in mutant embryos. Accompanying this expansion was the induction of paired zones of ectopic mammary development in the cervical region, which generated between three and five pairs of mammary placodes anterior to the first wild-type mammary rudiment. These rudiments expressed the mammary placode markers Wnt10b and Tbx3 and were labeled by antibodies to the mammary mesenchyme markers ERα and androgen receptor. Somitic Fgf10 expression, which is required for normal mammary line formation, was upregulated in mutant cervical somites, and conditional ablation of ectodermal Tbx3 expression eliminated all normally positioned and ectopic mammary placodes. We present evidence that Hoxc8 participates in regulating the initiation stages of mammary placode morphogenesis, and suggest that this and other Hox genes are likely to have important roles during regional specification and initiation of these and other cutaneous accessory organs. PMID:26459221

  11. Hoxc8 initiates an ectopic mammary program by regulating Fgf10 and Tbx3 expression and Wnt/β-catenin signaling.

    PubMed

    Carroll, Lara S; Capecchi, Mario R

    2015-12-01

    The role of Hox genes in the formation of cutaneous accessory organs such as hair follicles and mammary glands has proved elusive, a likely consequence of overlapping function and expression among various homeobox factors. Lineage and immunohistochemical analysis of Hoxc8 in mice revealed that this midthoracic Hox gene has transient but strong regional expression in ventrolateral surface ectoderm at E10.5, much earlier than previously reported. Targeted mice were generated to conditionally misexpress Hoxc8 from the Rosa locus using select Cre drivers, which significantly expanded the domain of thoracic identity in mutant embryos. Accompanying this expansion was the induction of paired zones of ectopic mammary development in the cervical region, which generated between three and five pairs of mammary placodes anterior to the first wild-type mammary rudiment. These rudiments expressed the mammary placode markers Wnt10b and Tbx3 and were labeled by antibodies to the mammary mesenchyme markers ERα and androgen receptor. Somitic Fgf10 expression, which is required for normal mammary line formation, was upregulated in mutant cervical somites, and conditional ablation of ectodermal Tbx3 expression eliminated all normally positioned and ectopic mammary placodes. We present evidence that Hoxc8 participates in regulating the initiation stages of mammary placode morphogenesis, and suggest that this and other Hox genes are likely to have important roles during regional specification and initiation of these and other cutaneous accessory organs.

  12. In vitro infectivity assay for mouse mammary tumor virus.

    PubMed

    Vacquier, J P; Cardiff, R D

    1979-08-01

    Studies of mouse mammary tumor virus (MMTV) have been impeded by the lack of an in vitro infectivity assay. We have developed a rapid, quantitative in vitro assay for MMTV infectivity based on the detection of positively staining foci by immunoperoxidase. This assay and a 50% end-point titration of MMTV infectivity gave identical virus titers. Infection of a rat hepatoma cell line, a feline kidney cell line, and a normal murine mammary gland cell line by virus from the mouse mammary tumor GR3A cell line was linear with respect to virus concentration. The infectious titers obtained in both homologous and heterologous cell lines were not significantly different, demonstrating a lack of host range specificity. Virus infectivity was inactivated by heating at 55 degrees C and by ultraviolet irradiation. Rabbit anti-MMTV serum neutralized the infectivity with a 50% neutralization end point of 1:5000. Applications of this assay to the study of the immunological, biological, and biochemical characteristics of MMTV are discussed.

  13. The effects of spaceflight on mammary metabolism in pregnant rats

    NASA Technical Reports Server (NTRS)

    Plaut, K.; Maple, R.; Vyas, C.; Munaim, S.; Darling, A.; Casey, T.; Alberts, J. R.

    1999-01-01

    The effects of spaceflight on mammary metabolism of 10 pregnant rats was measured on Day 20 of pregnancy and after parturition. Rats were flown on the space shuttle from Day 11 through Day 20 of pregnancy. After their return to earth, glucose oxidation to carbon dioxide increased 43% (P < 0.05), and incorporation into fatty acids increased 300% (P < 0.005) compared to controls. It is unclear whether the enhanced glucose use is due to spaceflight or a response to landing. Casein mRNA and gross histology were not altered at Day 20 of pregnancy. Six rats gave birth (on Day 22 to 23 of pregnancy) and mammary metabolic activity was measured immediately postpartum. The earlier effects of spaceflight were no longer apparent. There was also no difference in expression of beta-casein mRNA. It is clear from these studies that spaceflight does not impair the normal development of the mammary gland, its ability to use glucose, nor the ability to express mRNA for a major milk protein.

  14. Mammary gland involution is associated with rapid down regulation of major mammary Ca**2+-ATPases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sixty percent of calcium in milk is transported across the mammary cells apical membrane by the plasma membrane Ca**2+-ATPase 2 (PMCA2). The effect of abrupt cessation of milk production on the Ca**2+-ATPases and mammary calcium transport is unknown. We found that 24 hours after stopping milk prod...

  15. Morphological and histological characteristics of mammary dysplasias occurring in cell dissociation-derived murine mammary outgrowths

    SciTech Connect

    Ethier, S.P.; Adams, L.M.; Ullrich, R.L.

    1984-10-01

    The morphological and histological characteristics of ductal dysplasias that were observed in mammary outgrowths derived from monodispersed mammary cells of carcinogen-treated mice are described. Mammary outgrowths were derived by injecting either 10(4) or 10(5) enzymatically dissociated mammary cells, obtained from control or carcinogen-treated BALB/c mice, into gland-free mammary fat pads of syngeneic hosts. The mammary dysplasias observed varied considerably in morphological and histological characteristics. The majority of the lesions were ductal in origin and were associated with epithelial hyperplasia which ranged from mild hyperplasia, in which only a few extra layers of epithelium were present, to severe hyperplasia, in which the ducts and end buds were occluded and distended with epithelial cells. In addition, papillary and lobular lesions were observed which were also associated with varying degrees of hyperplasia. The range of mammary dysplasias observed in these outgrowths closely resembles that of lesions associated with the pathogenesis of mammary carcinoma in mice, rats, and humans.

  16. Mammary Fat Can Adjust Prolactin Effect on Mammary Epithelial Cells via Leptin and Estrogen.

    PubMed

    Feuermann, Yonatan; Mabjeesh, Sameer J; Shamay, Avi

    2009-01-01

    Leptin, like estrogen, is one of the endo/paracrine factors, which are synthesized in and secreted from mature adipocytes. The roles of the mammary fat pad and mammary adipocytes in the initiation of lactation are not clear. In this study, we showed that combination of prolactin, leptin and estrogen elevated the expression of the milk protein beta-lactoglobulin. We also showed that after prolactin stimulate the secretion of leptin from the mammary fat, leptin upregulated the expression of estrogen receptor alpha in the mammary epithelial cells. Also, prolactin affected aromatase mRNA expression in the bovine mammary fat and we demonstrated that leptin and prolactin can affect cholesterol secretion from explants in culture to the medium. Therefore, we suggest that prolactin initiates estrogen expression (as represented by aromatase mRNA) in the mammary fat pad, whereas leptin stimulates estrogen receptor alpha expression in the mammary epithelial cells. We hypothesize that leptin and estrogen, secreted from the mammary fat regulate lactation after stimulation of prolactin. PMID:20049155

  17. Dysfunctional telomeres promote genomic instability and metastasis in the absence of telomerase activity in oncogene induced mammary cancer.

    PubMed

    Bojovic, Bojana; Crowe, David L

    2013-02-01

    Telomerase is a ribonucleoprotein that maintains the ends of chromosomes (telomeres). In normal cells lacking telomerase activity, telomeres shorten with each cell division because of the inability to completely synthesize the lagging strand. Critically shortened telomeres elicit DNA damage responses and limit cellular division and lifespan, providing an important tumor suppressor function. Most human cancer cells express telomerase which contributes significantly to the tumor phenotype. In human breast cancer, telomerase expression is predictive of clinical outcomes such as lymph node metastasis and survival. In mouse models of mammary cancer, telomerase expression is also upregulated. Telomerase overexpression resulted in spontaneous mammary tumor development in aged female mice. Increased mammary cancer also was observed when telomerase deficient mice were crossed with p53 null mutant animals. However, the effects of telomerase and telomere length on oncogene driven mammary cancer have not been completely characterized. To address these issues we characterized neu proto-oncogene driven mammary tumor formation in G1 Terc-/- (telomerase deficient with long telomeres), G3 Terc-/- (telomerase deficient with short telomeres), and Terc+/+ mice. Telomerase deficiency reduced the number of mammary tumors and increased tumor latency regardless of telomere length. Decreased tumor formation correlated with increased apoptosis in Terc deficient tumors. Short telomeres dramatically increased lung metastasis which correlated with increased genomic instability, and specific alterations in DNA copy number and gene expression. We concluded that short telomeres promote metastasis in the absence of telomerase activity in neu oncogene driven mammary tumors.

  18. The mammary stem cell hierarchy: a looking glass into heterogeneous breast cancer landscapes.

    PubMed

    Sreekumar, Amulya; Roarty, Kevin; Rosen, Jeffrey M

    2015-12-01

    The mammary gland is a dynamic organ that undergoes extensive morphogenesis during the different stages of embryonic development, puberty, estrus, pregnancy, lactation and involution. Systemic and local cues underlie this constant tissue remodeling and act by eliciting an intricate pattern of responses in the mammary epithelial and stromal cells. Decades of studies utilizing methods such as transplantation and lineage-tracing have identified a complex hierarchy of mammary stem cells, progenitors and differentiated epithelial cells that fuel mammary epithelial development. Importantly, these studies have extended our understanding of the molecular crosstalk between cell types and the signaling pathways maintaining normal homeostasis that often are deregulated during tumorigenesis. While several questions remain, this research has many implications for breast cancer. Fundamental among these are the identification of the cells of origin for the multiple subtypes of breast cancer and the understanding of tumor heterogeneity. A deeper understanding of these critical questions will unveil novel breast cancer drug targets and treatment paradigms. In this review, we provide a current overview of normal mammary development and tumorigenesis from a stem cell perspective.

  19. Sasa health exerts a protective effect on Her2/NeuN mammary tumorigenesis.

    PubMed

    Ren, Mingqiang; Reilly, R Todd; Sacchi, Nicoletta

    2004-01-01

    Bamboo grass leaves of different Sasa species have been widely used in food and medicine in Eastern Asia for hundreds of years. Of special interest are Kumazasa (Sasa senanensis rehder) leaves used to prepare an alkaline extract known as Sasa Health. This extract was reported to inhibit both the development and growth of mammary tumors in a mammary tumor strain of virgin SHN mice (1). We found that Sasa Health exerts a significant protective effect on spontaneous mammary tumorigenesis in another mouse model of human breast cancer, the transgenic FVB-Her2/NeuN mouse model. Two cohorts of Her2/NeuN female mice of different age (eleven-week-old and twenty-four-week-old) chronically treated with Sasa Health in drinking water showed both a delay in the development of tumors and reduced tumor multiplicity. Sasa Health also induced inhibition of mammary duct branching and side bud development in association with reduced angiogenesis. Altogether these findings indicate that Sasa Health contains phytochemicals that can effectively retard spontaneous mammary tumorigenesis.

  20. Involvement of Connective Tissue Growth Factor (CTGF) in Insulin-like Growth Factor-I (IGF1) Stimulation of Proliferation of a Bovine Mammary Epithelial Cell Line

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insulin-like growth factor I (IGF1) plays an important role in mammary gland development and lactation in part by stimulating proliferation of the milk-producing epithelial cells. In this study, we used the bovine mammary epithelial cell line MAC-T cells as a model to understand the mechanism by whi...

  1. Prevalence of Glomerulopathies in Canine Mammary Carcinoma

    PubMed Central

    2016-01-01

    The incidence and prevalence of paraneoplastic glomerulopathy, especially associated with carcinoma, are a matter of debate and the causal link between cancer and glomerular diseases remains unclear. The aim of this study was to evaluate renal biopsies of selected bitches with spontaneous mammary gland carcinoma. We hypothesized that dogs with mammary carcinomas would show histologic evidence of glomerular pathology. A prospective study was performed in dogs with naturally occurring mammary carcinoma that were undergoing tumor resection and ovariohysterectomy. We evaluated renal biopsies of 32 bitches with spontaneous mammary gland carcinoma and 11 control dogs without mammary gland neoplasia. Samples were obtained from the left kidney and the biopsy material was divided for light microscopy (LM), immunofluorescence (IF) and transmission electron microscopy (TEM). Light microscopy abnormalities were identified in 78.1% of dogs with mammary carcinoma (n = 25) and in none of the dogs in the control group. Focal glomerular mesangial matrix expansion was the most common alteration (n = 15, 60.0%), but mesangial cell proliferation (n = 9, 36.0%) and focal segmental glomerulosclerosis (n = 9, 36.0%), synechiae (n = 7, 28.0%), and globally sclerotic glomeruli (n = 6, 24.0%) were also frequent in dogs with malignancy. Immunofluorescence microscopy revealed strong IgM staining was demonstrated in 64.3% (n = 18) of carcinoma dogs. Transmission electron microscopy from dogs with carcinoma revealed slight changes, the most frequent of which was faint sub-endothelial and mesangial deposits of electron-dense material (78%). Mesangial cell interpositioning and segmental effacement of podocyte foot processes were identified in some specimens (45%). Changes in the glomerulus and proteinuria are common in dogs with naturally occurring mammary carcinoma and this condition appears to provide an excellent large animal model for cancer-associated glomerulopathy in humans. PMID:27764139

  2. The normal and malignant mammary gland: a fresh look with ER beta onboard.

    PubMed

    Warner, M; Saji, S; Gustafsson, J A

    2000-07-01

    Estrogens are important for the development and function of the normal mammary gland as well as for development of mammary cancer. The frontline therapy for treatment of estrogen receptor (ER alpha) positive breast cancer is antiestrogens. A second estrogen receptor (ER beta) is also expressed in the breast but it has not been measured because it is not detected by the immunoassays used to detect ER alpha. In many cell systems ER beta has actions which are opposite to those of ER alpha and this finding has raised questions about the role of ER beta in the development and treatment of breast cancer.

  3. 9 CFR 310.17 - Inspection of mammary glands.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... mammary glands and diseased mammary glands of cattle, sheep, swine, and goats shall be removed without..., swine, and goats shall not be saved for edible purposes. (d) The udders from cows officially...

  4. ADAM17 in tumor associated leukocytes regulates inflammatory mediators and promotes mammary tumor formation

    PubMed Central

    Chuntova, Pavlina; Brady, Nicholas J.; Witschen, Patrice M.; Kemp, Sarah E.; Nelson, Andrew C.; Walcheck, Bruce; Schwertfeger, Kathryn L.

    2016-01-01

    The presence of inflammatory cells within the tumor microenvironment has been tightly linked to mammary tumor formation and progression. Specifically, interactions between tumor cells and infiltrating macrophages can contribute to the generation of a pro-tumorigenic microenvironment. Understanding the complex mechanisms that drive tumor cell-macrophage cross-talk will ultimately lead to the development of approaches to prevent or treat early stage breast cancers. As described here, we demonstrate that the cell surface protease a disintegrin and metalloproteinase 17 (ADAM17) is expressed by macrophages in mammary tumors and contributes to regulating the expression of pro-inflammatory mediators, including inflammatory cytokines and the inflammatory mediator cyclooxygenase-2 (Cox-2). Furthermore, we demonstrate that ADAM17 is expressed on leukocytes, including macrophages, within polyoma middle T (PyMT)-derived mammary tumors. Genetic deletion of ADAM17 in leukocytes resulted in decreased onset of mammary tumor growth, which was associated with reduced expression of the Cox-2 within the tumor. These findings demonstrate that ADAM17 regulates key inflammatory mediators in macrophages and that leukocyte-specific ADAM17 is an important promoter of mammary tumor initiation. Understanding the mechanisms associated with early stage tumorigenesis has implications for the development of preventive and/or treatment strategies for early stage breast cancers.

  5. Model of mouse mammary gland hyperproliferation and hyperplasia induced by a western-style diet.

    PubMed

    Xue, L; Newmark, H; Yang, K; Lipkin, M

    1996-01-01

    Mammary glands of female C57BL/6J mice were analyzed after they were fed a Western-style diet or control AIN-76A diet. The Western-style diet contained several risk factors found in human diets in geographic regions having increased risk for breast cancer: high fat and phosphate and low calcium and vitamin D. After they were fed these diets for 8, 14, and 20 weeks, mice were sacrificed, and mammary glands were removed for morphometric and radioautographic measurements. Although after the animals were fed the Western-style diet for 8 weeks the number of terminal ducts per mouse mammary gland (NTDMG) was similar in the Western-style and control diet groups, after they were fed the Western-style diet for 14 weeks (p < 0.05) and 20 weeks (p < 0.01) the NTDMG significantly increased compared with the control group. Moreover, there was a significant increase (p < 0.01) in the tritiated thymidine labeling index of mammary terminal ductal epithelial cells after 14 and 20 weeks of Western-style diet administration. Thus the Western-style diet induced increased epithelial cell proliferation and increased NTDMG in female mice when fed during young adult growth and development. The findings raise the possibility that the ingestion of a diet with Western-style fat and phosphate content and with low calcium and vitamin D may induce similar changes during the early development of the human mammary gland.

  6. Quantification of mammary organoid toxicant response and mammary tissue motility using OCT fluctuation spectroscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Yu, Xiao; Blackmon, Richard L.; Carabas-Hernendez, Patricia; Fuller, Ashley; Troester, Melissa A.; Oldenburg, Amy L.

    2016-03-01

    Mammary epithelial cell (MEC) organoids in 3D culture recapitulate features of breast ducts in vivo. OCT has the ability to monitor the evolution of MEC organoids non-invasively and longitudinally. The anti-cancer drug Doxorubicin (Dox) is able to inhibit proliferation of cancer cells and has been widely used for chemotherapy of breast cancers; while environmental toxins implicated in breast cancer such as estrogen regulates mammary tumor growth and stimulates the proliferation and metastatic potential of breast cancers. Here we propose a quantitative method for measuring motility of breast cells in 3D cultures based upon OCT speckle fluctuation spectroscopy. The metrics of the inverse power-law exponent (α) and fractional modulation amplitude (M) were extracted from speckle fluctuation spectra. These were used to quantify the responses of MEC organoids to Dox, and estrogen. We investigated MEC organoids comprised of two different MEC lines: MCF10DCIS.com exposed to Dox, and MCF7 exposed to estrogen. We found an increase (p<0.001) in α of MEC along time (t=0, 1 hour, 24 hours, 48 hours and 6 days) at each dose of Dox (0, 1 μM and 10 μM), indicating lower fluctuation intensity at higher frequencies. We also observed a decrease (p<0.001) in M for increasing time. However, both α and M of MCF7 treated with estrogen (0, 1 nM and 10 nM) exhibited the opposite trend along time. This novel technology provides rapid and non-invasive measurements of the effects of toxicants on MEC motility for understanding breast cancer development and assessing anti-cancer drugs.

  7. FAMILIAL MAMMARY TUMORS IN THE RABBIT

    PubMed Central

    Greene, Harry S. N.

    1940-01-01

    A series of experiments is described in which fragments derived from two mammary tumors of distinct types were transferred at different developmental stages to the anterior chamber of the eye of normal rabbits. It was found that the ability to survive and to grow progressively after transplantation was not immediately related to anaplastic cellular changes. On the other hand, there existed a definite correlation between the success of transplantation and the morphological relationship of tumor cells and the normal cells of the host. Transplantation to normal animals could not be effected during stages of local tissue invasion but was successfully performed as soon as the tumor cells manifested the ability to invade foreign tissues or to metastasize in the spontaneous host. It was concluded, therefore, that neither anaplasia nor local tissue invasion represented autonomy but, rather, stages in its development and that the final attainment of this condition was only evidenced by metastasis or by invasion in foreign tissues. The tumors were successfully transplanted to normal animals during this series of experiments and have been carried by serial transfer to the present time. The most outstanding feature in the transplantation of the papillary type tumor was the marked difference in susceptibility exhibited by the two sexes. The acinar type tumor was distinguished by high transplantability, an extremely rapid growth rate and early regression. PMID:19870965

  8. Prolactin affects leptin action in the bovine mammary gland via the mammary fat pad.

    PubMed

    Feuermann, Y; Mabjeesh, S J; Niv-Spector, L; Levin, D; Shamay, A

    2006-11-01

    One of the roles of the endocrine system is to synchronize mammary function. Hormones, such as estrogen, progesterone, and prolactin act directly on the mammary gland. Metabolic hormones, such as GH, glucocorticoids, insulin, and leptin are responsible for coordinating the body's response to metabolic homeostasis. Leptin has been shown to be an important factor in regulating the metabolic adaptation of nutrient partitioning during the energy-consuming processes of lactation. In the present study, we show that leptin is secreted from the mammary fat, and is regulated by prolactin. The expression of alpha-casein in a co-culture of epithelial cells and fat explants was enhanced by prolactin compared with that in epithelial cells cultured alone. Leptin antagonist abolished the effect of leptin on alpha-casein expression in mammary gland explants when exogenous leptin was not present in the medium. This finding supports our hypothesis that the antagonist abolishes the action of endogenous leptin secreted by the mammary adipocytes. These results lead us to the hypothesis that prolactin and leptin act in the bovine mammary gland, via mammary fat pad/adipocytes. PMID:17088410

  9. MicroRNA-206 is differentially expressed in Brca1-deficient mice and regulates epithelial and stromal cell compartments of the mouse mammary gland

    PubMed Central

    Wronski, A; Sandhu, G K; Milevskiy, M J G; Brewster, B L; Bridge, J A; Shewan, A M; Edwards, S L; French, J D; Brown, M A

    2016-01-01

    Depletion of Brca1 leads to defects in mouse mammary gland development and mammary tumors in humans and mice. To explore the role of microRNAs (miRNAs) in this process, we examined the mammary glands of MMTV-Cre Brca1Co/Co mice for differential miRNA expression using a candidate approach. Several miRNAs were differentially expressed in mammary tissue at day 1 of lactation and in mammary epithelial cell lines in which Brca1 messenger RNA (mRNA) levels have been reduced. Functional studies revealed that several of these miRNAs regulate mammary epithelial cell function in vitro, including miR-206. Creation and analysis of MMTV-miR-206 transgenic mice showed no effect on lactational mammary development and no tumors, but indicates a role in mammary tissue remodeling in mature mice, potentially involving Igf-1 and Sfrp1. These results indicate the potential of miRNAs to mediate the consequences of Brca1 loss and suggest a novel function for miR-206. PMID:27043663

  10. Fetal alcohol exposure and mammary tumorigenesis in offspring: role of the estrogen and insulin-like growth factor systems.

    PubMed

    Cohick, Wendie S; Crismale-Gann, Catina; Stires, Hillary; Katz, Tiffany A

    2015-01-01

    Fetal alcohol spectrum disorders affect a significant number of live births each year, indicating that alcohol consumption during pregnancy is an important public health issue. Environmental exposures and lifestyle choices during pregnancy may affect the offspring's risk of disease in adulthood, leading to the idea that a woman's risk of breast cancer may be pre-programmed prior to birth. Exposure of pregnant rats to alcohol increases tumorigenesis in the adult offspring in response to mammary carcinogens. The estrogen and insulin-like growth factor (IGF-I) axes occupy central roles in normal mammary gland development and breast cancer. 17-β estradiol (E2) and IGF-I synergize to regulate formation of terminal end buds and ductal elongation during pubertal development. The intracellular signaling pathways mediated by the estrogen and IGF-I receptors cross-talk at multiple levels through both genomic and non-genomic mechanisms. Several components of the E2 and IGF-I systems are altered in early development in rat offspring exposed to alcohol in utero, therefore, these changes may play a role in the enhanced susceptibility to mammary carcinogens observed in adulthood. Alcohol exposure in utero induces a number of epigenetic alterations in non-mammary tissues in the offspring and other adverse in utero exposures induce epigenetic modifications in the mammary gland. Future studies will determine if fetal alcohol exposure can induce epigenetic modifications in genes that regulate E2/IGF action at key phases of mammary development, ultimately leading to changes in susceptibility to carcinogens.

  11. 9 CFR 310.17 - Inspection of mammary glands.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... mammary glands and diseased mammary glands of cattle, sheep, swine, and goats shall be removed without... accordance with the provisions of part 311 of this subchapter. (c) Lactating mammary glands of cattle, sheep... as “Brucellosis reactors” or as “Mastitis elimination cows” shall be condemned....

  12. Disease-on-a-Chip: Mimicry of Tumor Growth in Mammary Ducts

    PubMed Central

    Vidi, Pierre-Alexandre; Maleki, Teimour; Ochoa, Manuel; Wang, Lei; Clark, Sara M.; Leary, James F.; Lelièvre, Sophie A.

    2013-01-01

    We present a disease-on-a-chip model in which cancer grows within phenotypically normal breast luminal epithelium on semicircular acrylic support mimicking portions of mammary ducts. The cells from tumor nodules developing within these hemichannels are morphologically distinct from their counterparts cultured on flat surfaces. Moreover, tumor nodules cocultured with the luminal epithelium in hemichannels display a different anticancer drug sensitivity compared to nodules cocultured with the luminal epithelium on a flat surface and to monocultures of tumor nodules. The mimicry of tumor development within the epithelial environment of mammary ducts provides a framework for the design and test of anticancer therapies. PMID:24202525

  13. Function of phosphoenolpyruvate carboxykinase in mammary gland epithelial cells[S

    PubMed Central

    Hsieh, Chang-Wen; Huang, Charles; Bederman, Ilya; Yang, Jianqi; Beidelschies, Michelle; Hatzoglou, Maria; Puchowicz, Michelle; Croniger, Colleen M.

    2011-01-01

    Previously, we have shown that Pck1 expression in mammary gland adipocytes and white adipose tissue maintains triglyceride stores through glyceroneogenesis, and these lipids were used for synthesis of milk triglycerides during lactation. Reduced milk triglycerides during lactation resulted in patterning of the newborn for insulin resistance. In this study, the role of Pck1 in mammary gland epithelial cells was analyzed. The developmental expression of Pck1 decreased in isolated mouse mammary gland epithelial cells through development and during lactation. Using HC11, a clonal mammary epithelial cell line, we found that both Janus kinase 2 signal transducers and activators of transcription 5 and the AKT pathways contributed to the repression of Pck1 mRNA by prolactin. These pathways necessitate three accessory factor regions of the Pck1 promoter for repression by prolactin. Using [U-13C6]glucose, [U-13C3]pyruvate, and [U-13C3]glycerol in HC11 cells, we determined that Pck1 functions in the pathway for the conversion of gluconeogenic precursors to glucose and contributes to glycerol-3-phosphate synthesis through glyceroneogenesis. Therefore, Pck1 plays an important role in both the mammary gland adipocytes and epithelial cells during lactation. PMID:21504969

  14. Functional adaptations of the transcriptome to mastitis-causing pathogens: the mammary gland and beyond.

    PubMed

    Loor, Juan J; Moyes, Kasey M; Bionaz, Massimo

    2011-12-01

    Application of microarrays to the study of intramammary infections in recent years has provided a wealth of fundamental information on the transcriptomics adaptation of tissue/cells to the disease. Due to its heavy toll on productivity and health of the animal, in vivo and in vitro transcriptomics works involving different mastitis-causing pathogens have been conducted on the mammary gland, primarily on livestock species such as cow and sheep, with few studies in non-ruminants. However, the response to an infectious challenge originating in the mammary gland elicits systemic responses in the animal and encompasses tissues such as liver and immune cells in the circulation, with also potential effects on other tissues such as adipose. The susceptibility of the animal to develop mastitis likely is affected by factors beyond the mammary gland, e.g. negative energy balance as it occurs around parturition. Objectives of this review are to discuss the use of systems biology concepts for the holistic study of animal responses to intramammary infection; providing an update of recent work using transcriptomics to study mammary and peripheral tissue (i.e. liver) as well as neutrophils and macrophage responses to mastitis-causing pathogens; discuss the effect of negative energy balance on mastitis predisposition; and analyze the bovine and murine mammary innate-immune responses during lactation and involution using a novel functional analysis approach to uncover potential predisposing factors to mastitis throughout an animal's productive life.

  15. Protein quality and quantity and insulin control of mammary gland glucose utilization during lactation

    SciTech Connect

    Masor, M.L.

    1987-01-01

    Virgin Sprague-Dawley rats were bred, and fed laboratory stock (STOCK), 13% casein plus methionine, 13% wheat gluten, or 5% casein plus methionine through gestation and 4 days of lactation. Diets were switched at parturition to determine the effects of dietary protein quality and quantity fed during gestation and/or lactation on insulin stimulation of mammary glucose utilization. On day 20 of gestation (20G) and day 4 of lactation (4L) the right inguinal-abdominal mammary glands were removed, and acini and tissue slices were incubated in Krebs buffer with or without insulin containing (U-/sup 14/C)-glucose and 5mM glucose for 1 hour at 37/degrees/C. Glucose incorporation into CO/sub 2/, lipid and lactose was determined. Glucose incorporation into CO/sub 2/ and lipid, but not lactose was stimulated by insulin in mammary slices. Diet effects on glucose utilization in acini were confirmed in slices for basal and insulin stimulated levels. Treatment affected the absolute increase of insulin stimulation. Regression analysis significantly correlated pup weight gain with total glucose utilization. Poor dietary protein quality and quantity fed during gestation impaired both overall response of mammary glucose utilization to insulin stimulation, and mammary development during pregnancy. Improving protein value at parturition did not overcome those deficits by 4L.

  16. Three-dimensional Mammary Epithelial Cell Morphogenesis Model for Analysis of TGFß Signaling.

    PubMed

    Rashidian, Juliet; Luo, Kunxin

    2016-01-01

    Culturing mammary epithelial cells in laminin-rich extracellular matrices (three dimensional or 3D culture) offers significant advantages over that in the conventional two-dimensional (2D) tissue culture system in that it takes into considetation the impact of extracellular matrix (ECM) microenvironment on the proliferation, survival, and differentiation of mammary epithelial cells. When grown in the 3D culture, untransformed mammary epithelial cells undergo morphogenesis to form a multicellular and polarized acini-like structure that functionally mimics the differentiated alveoli in the pregnancy mammary gland. This process is subjected to regulation by many growth factors and cytokines. The transforming growth factor-ß (TGFß) is a multipotent cytokine that regulates multiple aspects of development and tumorigenesis. In addition to its effects on epithelial cell proliferation, survival, and differentiation, it is also a potent regulator of the cell-matrix interaction. Thus, the 3D culture model may recapitulate the complex in vivo epithelial cell microenvironment and allow us to fully evaluate the role of TGFß signaling in multiple aspects of normal and cancerous cell behavior. In this chapter we provide detailed protocols for growing mammary epithelial cells in the 3D Matrigel for analysis of signaling pathways.

  17. Mammary stem cells have myoepithelial cell properties

    PubMed Central

    Prater, Michael D.; Petit, Valérie; Russell, I. Alasdair; Giraddi, Rajshekhar; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F.; Metzger, Daniel; Faraldo, Marisa M.; Deugnier, Marie-Ange; Glukhova, Marina A.; Stingl, John

    2014-01-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt acin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using 2 independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage tracing approach we follow the progeny of α-smooth muscle actin-expressing myoepithelial cells and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy. PMID:25173976

  18. Mechanical strain induces involution-associated events in mammary epithelial cells

    PubMed Central

    Quaglino, Ana; Salierno, Marcelo; Pellegrotti, Jesica; Rubinstein, Natalia; Kordon, Edith C

    2009-01-01

    Background Shortly after weaning, a complex multi-step process that leads to massive epithelial apoptosis is triggered by tissue local factors in the mouse mammary gland. Several reports have demonstrated the relevance of mechanical stress to induce adaptive responses in different cell types. Interestingly, these signaling pathways also participate in mammary gland involution. Then, it has been suggested that cell stretching caused by milk accumulation after weaning might be the first stimulus that initiates the complete remodeling of the mammary gland. However, no previous report has demonstrated the impact of mechanical stress on mammary cell physiology. To address this issue, we have designed a new practical device that allowed us to evaluate the effects of radial stretching on mammary epithelial cells in culture. Results We have designed and built a new device to analyze the biological consequences of applying mechanical stress to cells cultured on flexible silicone membranes. Subsequently, a geometrical model that predicted the percentage of radial strain applied to the elastic substrate was developed. By microscopic image analysis, the adjustment of these calculations to the actual strain exerted on the attached cells was verified. The studies described herein were all performed in the HC11 non-tumorigenic mammary epithelial cell line, which was originated from a pregnant BALB/c mouse. In these cells, as previously observed in other tissue types, mechanical stress induced ERK1/2 phosphorylation and c-Fos mRNA and protein expression. In addition, we found that mammary cell stretching triggered involution associated cellular events as Leukemia Inhibitory Factor (LIF) expression induction, STAT3 activation and AKT phosphorylation inhibition. Conclusion Here, we show for the first time, that mechanical strain is able to induce weaning-associated events in cultured mammary epithelial cells. These results were obtained using a new practical and affordable device

  19. Natural and abrupt involution of the mammary gland affects differently the metabolic and health consequences of weaning.

    PubMed

    Silanikove, Nissim

    2014-04-25

    In most mammals under natural conditions weaning is gradual. Weaning occurs after the mammary gland naturally produces much less milk than it did at peak and established lactation. Involution occurs following the cessation of milk evacuation from the mammary glands. The abrupt termination of the evacuation of milk from the mammary gland at peak and established lactation induces abrupt involution. Evidence on mice has shown that during abrupt involution, mammary gland utilizes some of the same tissue remodeling programs that are activated during wound healing. These results led to the proposition of the "involution hypothesis". According to the involution hypothesis, involution is associated with increased risk for developing breast cancer. However, the involution hypothesis is challenged by the metabolic and immunological events that characterize the involution process that follows gradual weaning. It has been shown that gradual weaning is associated with pre-adaption to the forthcoming break between dam and offspring and is followed by an orderly reprogramming of the mammary gland tissue. As discussed herein, such response may actually protect the mammary glands against the development of breast cancer and thus, may explain the protective effect of extended breastfeeding. On the other hand, the termination of breastfeeding during the first 6 months of lactation is likely associated with an abrupt involution and thus with an increased risk for developing breast cancer. Review of the literature on the epidemiology of breast cancer principally supports those conclusions.

  20. Growth of human normal and neoplastic mammary tissues in the cleared mammary fat pad of the nude mouse.

    PubMed

    Outzen, H C; Custer, R P

    1975-12-01

    Dysplastic and malignant human breast tissues were grown successfully in the cleared mammary fat pads (CFP) of nude mice. The mammary fat pads were cleared while the mice were in a germfree isolator. Prepared mice were removed fron the germfree enviornment to facilitate transplantation of the human mammary tissue into their CFP and subsequently were maintained in sterile laminar flow racks.

  1. Measurement by radioimmunoassay of casein content in rabbit mammary gland during pregnancy and after prolactin stimulation in organ culture

    SciTech Connect

    Jahn, G.; Dusanter-Fourt, I.; Kelly, P.A.; Houdebine, L.M.; Djiane, J.

    1987-01-01

    A specific homologous radioimmunoassay was developed to measure rabbit ..beta..-casein in rabbit mammary gland with a sensitivity of 0.5 ng/ml protein. It was used to measure casein concentration during pregnancy and in organ culture of mammary gland explants. Casein was detectable in virgin mammary glands, showed a small increase during the first half of pregnancy, increased more than 20-fold between Days 21 and 27, and diminished somewhat on the first days of lactation. After 24 hr of culture, mammary gland explants had no detectable casein, but the addition of increasing concentrations of prolactin to a culture medium which contained insulin (5 ..mu..g/ml) and cortisol (0.5 ..mu..g/ml) induced a regular increase in the casein content of the tissue. Casein started to increase when 10 ng/ml of prolactin was present and maximal values were achieved for 100 ng/ml of the hormone.

  2. Critical role of the stress chaperone GRP78/BiP in tumor proliferation, survival, and tumor angiogenesis in transgene-induced mammary tumor development.

    PubMed

    Dong, Dezheng; Ni, Min; Li, Jianze; Xiong, Shigang; Ye, Wei; Virrey, Jenilyn J; Mao, Changhui; Ye, Risheng; Wang, Miao; Pen, Ligaya; Dubeau, Louis; Groshen, Susan; Hofman, Florence M; Lee, Amy S

    2008-01-15

    The unfolded protein response (UPR) is an evolutionarily conserved mechanism that activates both proapoptotic and survival pathways to allow eukaryotic cells to adapt to endoplasmic reticulum (ER) stress. Although the UPR has been implicated in tumorigenesis, its precise role in endogenous cancer remains unclear. A major UPR protective response is the induction of the ER chaperone GRP78/BiP, which is expressed at high levels in a variety of tumors and confers drug resistance in both proliferating and dormant cancer cells. To determine the physiologic role of GRP78 in in situ-generated tumor and the consequence of its suppression on normal organs, we used a genetic model of breast cancer in the Grp78 heterozygous mice where GRP78 expression level was reduced by about half, mimicking anti-GRP78 agents that achieve partial suppression of GRP78 expression. Here, we report that Grp78 heterozygosity has no effect on organ development or antibody production but prolongs the latency period and significantly impedes tumor growth. Our results reveal three major mechanisms mediated by GRP78 for cancer progression: enhancement of tumor cell proliferation, protection against apoptosis, and promotion of tumor angiogenesis. Importantly, although partial reduction of GRP78 in the Grp78 heterozygous mice substantially reduces the tumor microvessel density, it has no effect on vasculature of normal organs. Our findings establish that a key UPR target GRP78 is preferably required for pathophysiologic conditions, such as tumor proliferation, survival, and angiogenesis, underscoring its potential value as a novel therapeutic target for dual antitumor and antiangiogenesis activity.

  3. ADVERSE EFFECTS OF PRENATAL EXPOSURE TO ATRAZINE DURING A CRITICAL PERIOD OF MAMMARY GLAND GROWTH

    EPA Science Inventory

    Prenatal exposure to 100 mg/kg atrazine (ATR) was previously shown to delay mammary gland (MG) development in the female offspring of Long Evans (LE) rats. To determine if the fetal MG was most sensitive to ATR effects during specific periods of development, timed-pregnant dams ...

  4. Transcriptional repressor Tbx3 is required for the hormone-sensing cell lineage in mammary epithelium.

    PubMed

    Kunasegaran, Kamini; Ho, Victor; Chang, Ted H-T; De Silva, Duvini; Bakker, Martijn L; Christoffels, Vincent M; Pietersen, Alexandra M

    2014-01-01

    The transcriptional repressor Tbx3 is involved in lineage specification in several tissues during embryonic development. Germ-line mutations in the Tbx3 gene give rise to Ulnar-Mammary Syndrome (comprising reduced breast development) and Tbx3 is required for mammary epithelial cell identity in the embryo. Notably Tbx3 has been implicated in breast cancer, which develops in adult mammary epithelium, but the role of Tbx3 in distinct cell types of the adult mammary gland has not yet been characterized. Using a fluorescent reporter knock-in mouse, we show that in adult virgin mice Tbx3 is highly expressed in luminal cells that express hormone receptors, and not in luminal cells of the alveolar lineage (cells primed for milk production). Flow cytometry identified Tbx3 expression already in progenitor cells of the hormone-sensing lineage and co-immunofluorescence confirmed a strict correlation between estrogen receptor (ER) and Tbx3 expression in situ. Using in vivo reconstitution assays we demonstrate that Tbx3 is functionally relevant for this lineage because knockdown of Tbx3 in primary mammary epithelial cells prevented the formation of ER+ cells, but not luminal ER- or basal cells. Interestingly, genes that are repressed by Tbx3 in other cell types, such as E-cadherin, are not repressed in hormone-sensing cells, highlighting that transcriptional targets of Tbx3 are cell type specific. In summary, we provide the first analysis of Tbx3 expression in the adult mammary gland at a single cell level and show that Tbx3 is important for the generation of hormone-sensing cells.

  5. Transcriptional Repressor Tbx3 Is Required for the Hormone-Sensing Cell Lineage in Mammary Epithelium

    PubMed Central

    Kunasegaran, Kamini; Ho, Victor; Chang, Ted H-. T.; De Silva, Duvini; Bakker, Martijn L.; Christoffels, Vincent M.; Pietersen, Alexandra M.

    2014-01-01

    The transcriptional repressor Tbx3 is involved in lineage specification in several tissues during embryonic development. Germ-line mutations in the Tbx3 gene give rise to Ulnar-Mammary Syndrome (comprising reduced breast development) and Tbx3 is required for mammary epithelial cell identity in the embryo. Notably Tbx3 has been implicated in breast cancer, which develops in adult mammary epithelium, but the role of Tbx3 in distinct cell types of the adult mammary gland has not yet been characterized. Using a fluorescent reporter knock-in mouse, we show that in adult virgin mice Tbx3 is highly expressed in luminal cells that express hormone receptors, and not in luminal cells of the alveolar lineage (cells primed for milk production). Flow cytometry identified Tbx3 expression already in progenitor cells of the hormone-sensing lineage and co-immunofluorescence confirmed a strict correlation between estrogen receptor (ER) and Tbx3 expression in situ. Using in vivo reconstitution assays we demonstrate that Tbx3 is functionally relevant for this lineage because knockdown of Tbx3 in primary mammary epithelial cells prevented the formation of ER+ cells, but not luminal ER- or basal cells. Interestingly, genes that are repressed by Tbx3 in other cell types, such as E-cadherin, are not repressed in hormone-sensing cells, highlighting that transcriptional targets of Tbx3 are cell type specific. In summary, we provide the first analysis of Tbx3 expression in the adult mammary gland at a single cell level and show that Tbx3 is important for the generation of hormone-sensing cells. PMID:25343378

  6. Remodeling of Endogenous Mammary Epithelium by Breast Cancer Stem Cells

    PubMed Central

    Parashurama, Natesh; Lobo, Neethan A.; Ito, Ken; Mosley, Adriane R.; Habte, Frezghi G.; Zabala, Maider; Smith, Bryan R.; Lam, Jessica; Weissman, Irving L.; Clarke, Michael F.; Gambhir, Sanjiv S.

    2014-01-01

    Poorly regulated tissue remodeling results in increased breast cancer risk, yet how breast cancer stem cells (CSC) participate in remodeling is unknown. We performed in vivo imaging of changes in fluorescent, endogenous duct architecture as a metric for remodeling. First, we quantitatively imaged physiologic remodeling of primary branches of the developing and regenerating mammary tree. To assess CSC-specific remodeling events, we isolated CSC from MMTV-Wnt1 (mouse mammary tumor virus long-term repeat enhancer driving Wnt1 oncogene) breast tumors, a well studied model in which tissue remodeling affects tumorigenesis. We confirm that CSC drive tumorigenesis, suggesting a link between CSC and remodeling. We find that normal, regenerating, and developing gland maintain a specific branching pattern. In contrast, transplantation of CSC results in changes in the branching patterns of endogenous ducts while non-CSC do not. Specifically, in the presence of CSC, we identified an increased number of branches, branch points, ducts which have greater than 40 branches (5/33 for CSC and 0/39 for non-CSC), and histological evidence of increased branching. Moreover, we demonstrate that only CSC implants invade into surrounding stroma with structures similar to developing mammary ducts (nine for CSC and one for non-CSC). Overall, we demonstrate a novel approach for imaging physiologic and pathological remodeling. Furthermore, we identify unique, CSC-specific, remodeling events. Our data suggest that CSC interact with the microenvironment differently than non-CSC, and that this could eventually be a therapeutic approach for targeting CSC. PMID:22899386

  7. Remodeling of endogenous mammary epithelium by breast cancer stem cells.

    PubMed

    Parashurama, Natesh; Lobo, Neethan A; Ito, Ken; Mosley, Adriane R; Habte, Frezghi G; Zabala, Maider; Smith, Bryan R; Lam, Jessica; Weissman, Irving L; Clarke, Michael F; Gambhir, Sanjiv S

    2012-10-01

    Poorly regulated tissue remodeling results in increased breast cancer risk, yet how breast cancer stem cells (CSC) participate in remodeling is unknown. We performed in vivo imaging of changes in fluorescent, endogenous duct architecture as a metric for remodeling. First, we quantitatively imaged physiologic remodeling of primary branches of the developing and regenerating mammary tree. To assess CSC-specific remodeling events, we isolated CSC from MMTV-Wnt1 (mouse mammary tumor virus long-term repeat enhancer driving Wnt1 oncogene) breast tumors, a well studied model in which tissue remodeling affects tumorigenesis. We confirm that CSC drive tumorigenesis, suggesting a link between CSC and remodeling. We find that normal, regenerating, and developing gland maintain a specific branching pattern. In contrast, transplantation of CSC results in changes in the branching patterns of endogenous ducts while non-CSC do not. Specifically, in the presence of CSC, we identified an increased number of branches, branch points, ducts which have greater than 40 branches (5/33 for CSC and 0/39 for non-CSC), and histological evidence of increased branching. Moreover, we demonstrate that only CSC implants invade into surrounding stroma with structures similar to developing mammary ducts (nine for CSC and one for non-CSC). Overall, we demonstrate a novel approach for imaging physiologic and pathological remodeling. Furthermore, we identify unique, CSC-specific, remodeling events. Our data suggest that CSC interact with the microenvironment differently than non-CSC, and that this could eventually be a therapeutic approach for targeting CSC. PMID:22899386

  8. Bioengineered silk scaffolds in 3D tissue modeling with focus on mammary tissues.

    PubMed

    Maghdouri-White, Yas; Bowlin, Gary L; Lemmon, Christopher A; Dréau, Didier

    2016-02-01

    In vitro generation of three-dimensional (3D) biological tissues and organ-like structures is a promising strategy to study and closely model complex aspects of the molecular, cellular, and physiological interactions of tissue. In particular, in vitro 3D tissue modeling holds promises to further our understanding of breast development. Indeed, biologically relevant 3D structures that combine mammary cells and engineered matrices have improved our knowledge of mammary tissue growth, organization, and differentiation. Several polymeric biomaterials have been used as scaffolds to engineer 3D mammary tissues. Among those, silk fibroin-based biomaterials have many biologically relevant properties and have been successfully used in multiple medical applications. Here, we review the recent advances in engineered scaffolds with an emphasis on breast-like tissue generation and the benefits of modified silk-based scaffolds.

  9. Pleural effusion secondary to thoracic metastatic mammary adenocarcinoma in a mare.

    PubMed

    Foreman, J H; Weidner, J P; Parry, B W; Hargis, A

    1990-11-01

    A 17-year-old Quarter Horse mare was examined nearly 3 years after excision and cryotherapy of a papillary mammary gland adenocarcinoma. The mare had been used for pleasure riding since surgery, but had recently developed progressive dyspnea. The mare had clinical evidence of pleural effusion, but died before further clinical examination and treatment were instituted. Necropsy revealed deep mammary masses with similar nodules in the deep inguinal, renal, and mediastinal lymph nodes and in the lungs, pericardium, visceral and parietal pleurae, and left ovary. The masses were identified as papillary mammary gland adenocarcinoma. Large volumes of free pleural and peritoneal fluid were detected. The pleural fluid contained similar neoplastic cells that could have been readily detected by exfoliative cytologic examination had the mare survived. PMID:2254151

  10. MTA family of transcriptional metaregulators in mammary gland morphogenesis and breast cancer.

    PubMed

    Singh, Rajesh R; Kumar, Rakesh

    2007-09-01

    Since breast cancer and its associated metastasis are a global health problem and a major cause of mortality among women, research efforts to understand the development, morphogenesis, and functioning of the mammary gland are a high priority. Myriad signaling pathways, transcription factors, and associated transcriptional coregulators have been identified in both normal functioning and neoplastic transformation of the mammary gland. The discovery of the metastasis tumor antigen 1 (MTA1) gene, its overexpression in cancer and metastasis and its subsequent identification as an integral part of the chromatin remodeling complex heralded extensive research on its physiological role. Subsequent identification of additional gene family members, namely MTA1s, MTA2, and MTA3, and their functions in the cell has resulted in the establishment of the significance of the MTA family. The role of these proteins in modulating hormonal responses in normal mammary glands and in breast cancer has resulted in their identification as important molecular markers and potential therapeutic targets.

  11. Fibroadenomas of anogenital mammary-like glands: from embryogenesis anomaly to apocrine origin.

    PubMed

    Amalinei, Cornelia; Giusca, Simona E; Caruntu, Irina D

    2015-09-01

    Mammary-like anogenital fibroadenomas are rare entities within the wide spectrum of female genital pathology. Our paper provides an up-to-date review, by systematization of the concepts and controversies, from the origin to the development and the diagnosis of the lesion. The theories pertaining to its histogenesis incorporate its debated origin of ectopic mammary-derived lesions, of cutaneous apocrine, eccrine, sebaceous, and mammary-like anogenital glands. Although rare, both clinicians and pathologists should consider this lesion type within the differential diagnosis of anogenital pathology, regardless of the woman's age, and pathological confirmation is mandatory to exclude the possibility of other tumours, including malignancy. Immunohistochemistry may represent a useful tool in tumor characterisation and in differential diagnosis. PMID:26619099

  12. 3D Culture Assays of Murine Mammary Branching Morphogenesis and Epithelial Invasion

    PubMed Central

    Nguyen-Ngoc, Kim-Vy; Shamir, Eliah R.; Huebner, Robert J.; Beck, Jennifer N.; Cheung, Kevin J.; Ewald, Andrew J.

    2016-01-01

    Epithelia are fundamental tissues that line cavities, glands, and outer body surfaces. We use three-dimensional (3D) embedded culture of primary murine mammary epithelial ducts, called “organoids,” to recapitulate in days in culture epithelial programs that occur over weeks deep within the body. Modulating the composition of the extracellular matrix (ECM) allows us to model cell- and tissue-level behaviors observed in normal development, such as branching morphogenesis, and in cancer, such as invasion and dissemination. Here, we describe a collection of protocols for 3D culture of mammary organoids in different ECMs and for immunofluorescence staining of 3D culture samples and mammary gland tissue sections. We illustrate expected phenotypic outcomes of each assay and provide troubleshooting tips for commonly encountered technical problems. PMID:25245692

  13. Essential role for a novel population of binucleated mammary epithelial cells in lactation.

    PubMed

    Rios, Anne C; Fu, Nai Yang; Jamieson, Paul R; Pal, Bhupinder; Whitehead, Lachlan; Nicholas, Kevin R; Lindeman, Geoffrey J; Visvader, Jane E

    2016-01-01

    The mammary gland represents a unique tissue to study organogenesis as it predominantly develops in the post-natal animal and undergoes dramatic morphogenetic changes during puberty and the reproductive cycle. The physiological function of the mammary gland is to produce milk to sustain the newborn. Here we view the lactating gland through three-dimensional confocal imaging of intact tissue. We observed that the majority of secretory alveolar cells are binucleated. These cells first arise in very late pregnancy due to failure of cytokinesis and are larger than mononucleated cells. Augmented expression of Aurora kinase-A and Polo-like kinase-1 at the lactogenic switch likely mediates the formation of binucleated cells. Our findings demonstrate an important physiological role for polyploid mammary epithelial cells in lactation, and based on their presence in five different species, suggest that binucleated cells evolved to maximize milk production and promote the survival of offspring across all mammalian species. PMID:27102712

  14. Essential role for a novel population of binucleated mammary epithelial cells in lactation.

    PubMed

    Rios, Anne C; Fu, Nai Yang; Jamieson, Paul R; Pal, Bhupinder; Whitehead, Lachlan; Nicholas, Kevin R; Lindeman, Geoffrey J; Visvader, Jane E

    2016-04-22

    The mammary gland represents a unique tissue to study organogenesis as it predominantly develops in the post-natal animal and undergoes dramatic morphogenetic changes during puberty and the reproductive cycle. The physiological function of the mammary gland is to produce milk to sustain the newborn. Here we view the lactating gland through three-dimensional confocal imaging of intact tissue. We observed that the majority of secretory alveolar cells are binucleated. These cells first arise in very late pregnancy due to failure of cytokinesis and are larger than mononucleated cells. Augmented expression of Aurora kinase-A and Polo-like kinase-1 at the lactogenic switch likely mediates the formation of binucleated cells. Our findings demonstrate an important physiological role for polyploid mammary epithelial cells in lactation, and based on their presence in five different species, suggest that binucleated cells evolved to maximize milk production and promote the survival of offspring across all mammalian species.

  15. Luminal epithelial cells within the mammary gland can produce basal cells upon oncogenic stress.

    PubMed

    Hein, S M; Haricharan, S; Johnston, A N; Toneff, M J; Reddy, J P; Dong, J; Bu, W; Li, Y

    2016-03-17

    In the normal mammary gland, the basal epithelium is known to be bipotent and can generate either basal or luminal cells, whereas the luminal epithelium has not been demonstrated to contribute to the basal compartment in an intact and normally developed mammary gland. It is not clear whether cellular heterogeneity within a breast tumor results from transformation of bipotent basal cells or from transformation and subsequent basal conversion of the more differentiated luminal cells. Here we used a retroviral vector to express an oncogene specifically in a small number of the mammary luminal epithelial cells and tested their potential to produce basal cells during tumorigenesis. This in-vivo lineage-tracing work demonstrates that luminal cells are capable of producing basal cells on activation of either polyoma middle T antigen or ErbB2 signaling. These findings reveal the plasticity of the luminal compartment during tumorigenesis and provide an explanation for cellular heterogeneity within a cancer.

  16. Quantitative Assessment of Mouse Mammary Gland Morphology Using Automated Digital Image Processing and TEB Detection.

    PubMed

    Blacher, Silvia; Gérard, Céline; Gallez, Anne; Foidart, Jean-Michel; Noël, Agnès; Péqueux, Christel

    2016-04-01

    The assessment of rodent mammary gland morphology is largely used to study the molecular mechanisms driving breast development and to analyze the impact of various endocrine disruptors with putative pathological implications. In this work, we propose a methodology relying on fully automated digital image analysis methods including image processing and quantification of the whole ductal tree and of the terminal end buds as well. It allows to accurately and objectively measure both growth parameters and fine morphological glandular structures. Mammary gland elongation was characterized by 2 parameters: the length and the epithelial area of the ductal tree. Ductal tree fine structures were characterized by: 1) branch end-point density, 2) branching density, and 3) branch length distribution. The proposed methodology was compared with quantification methods classically used in the literature. This procedure can be transposed to several software and thus largely used by scientists studying rodent mammary gland morphology. PMID:26910307

  17. Essential role for a novel population of binucleated mammary epithelial cells in lactation

    PubMed Central

    Rios, Anne C.; Fu, Nai Yang; Jamieson, Paul R.; Pal, Bhupinder; Whitehead, Lachlan; Nicholas, Kevin R.; Lindeman, Geoffrey J.; Visvader, Jane E.

    2016-01-01

    The mammary gland represents a unique tissue to study organogenesis as it predominantly develops in the post-natal animal and undergoes dramatic morphogenetic changes during puberty and the reproductive cycle. The physiological function of the mammary gland is to produce milk to sustain the newborn. Here we view the lactating gland through three-dimensional confocal imaging of intact tissue. We observed that the majority of secretory alveolar cells are binucleated. These cells first arise in very late pregnancy due to failure of cytokinesis and are larger than mononucleated cells. Augmented expression of Aurora kinase-A and Polo-like kinase-1 at the lactogenic switch likely mediates the formation of binucleated cells. Our findings demonstrate an important physiological role for polyploid mammary epithelial cells in lactation, and based on their presence in five different species, suggest that binucleated cells evolved to maximize milk production and promote the survival of offspring across all mammalian species. PMID:27102712

  18. Canine Mammary Tumours Are Affected by Frequent Copy Number Aberrations, including Amplification of MYC and Loss of PTEN

    PubMed Central

    Borge, Kaja S.; Nord, Silje; Van Loo, Peter; Lingjærde, Ole C.; Gunnes, Gjermund; Alnæs, Grethe I. G.; Solvang, Hiroko K.; Lüders, Torben; Kristensen, Vessela N.; Børresen-Dale, Anne-Lise; Lingaas, Frode

    2015-01-01

    Background Copy number aberrations frequently occur during the development of many cancers. Such events affect dosage of involved genes and may cause further genomic instability and progression of cancer. In this survey, canine SNP microarrays were used to study 117 canine mammary tumours from 69 dogs. Results We found a high occurrence of copy number aberrations in canine mammary tumours, losses being more frequent than gains. Increased frequency of aberrations and loss of heterozygosity were positively correlated with increased malignancy in terms of histopathological diagnosis. One of the most highly recurrently amplified regions harbored the MYC gene. PTEN was located to a frequently lost region and also homozygously deleted in five tumours. Thus, deregulation of these genes due to copy number aberrations appears to be an important event in canine mammary tumour development. Other potential contributors to canine mammary tumour pathogenesis are COL9A3, INPP5A, CYP2E1 and RB1. The present study also shows that a more detailed analysis of chromosomal aberrations associated with histopathological parameters may aid in identifying specific genes associated with canine mammary tumour progression. Conclusions The high frequency of copy number aberrations is a prominent feature of canine mammary tumours as seen in other canine and human cancers. Our findings share several features with corresponding studies in human breast tumours and strengthen the dog as a suitable model organism for this disease. PMID:25955013

  19. Metastatic mammary carcinoma to the orbit masquerading as maxillary sinusitis

    PubMed Central

    Abo-Shasha, Rami; Stepniak, Camilla; Yeh, David H.

    2016-01-01

    Introduction: We report on a case of isolated metastatic breast cancer to the medial rectus muscle. This entity is exceedingly rare. Case: A 44-year-old female with a history of breast cancer presented with unilateral maxillary symptoms and was treated for sinusitis. Over time, she developed ocular pain, diplopia, blurred vision and eventually complete adduction deficit. Results: T1-weighted magnetic resonance imaging revealed a medial rectus lesion. Biopsy via transnasal transorbital endoscopic approach revealed metastatic mammary carcinoma. Discussion: Metastatic disease to the orbit should be considered in the differential diagnosis of refractory maxillary sinus pain in patients with a known underlying malignancy. PMID:27103558

  20. Suppression of ICE and Apoptosis in Mammary Epithelial Cells by Extracellular Matrix

    SciTech Connect

    Boudreau, Nancy; Sympson, C. J.; Werb, Zena; Bissell, Mina J.

    1994-12-01

    Apoptosis (programmed cell death) plays a major role in development and tissue regeneration. Basement membrane extracellular matrix (ECM), but not fibronectin or collagen, was shown to suppress apoptosis of mammary epithelial cells in tissue culture and in vivo. Apoptosis was induced by antibodies to beta 1 integrins or by overexpression of stromelysin-1, which degrades ECM. Expression of interleukin-1 beta converting enzyme (ICE) correlated with the loss of ECM, and inhibitors of ICE activity prevented apoptosis. These results suggest that ECM regulates apoptosis in mammary epithelial cells through an integrin-dependent negative regulation of ICE expression.

  1. CLINICOPATHOLOGIC FEATURES OF MAMMARY MASSES IN CAPTIVE LIONS (PANTHERA LEO).

    PubMed

    Sadler, Ryan A; Craig, Linden E; Ramsay, Edward C; Helmick, Kelly; Collins, Darin; Garner, Michael M

    2016-03-01

    A multi-institutional retrospective analysis of 330 pathology accessions from 285 different lions found 15 captive, female African lions (Panthera leo) with confirmed mammary masses. Aside from the presence of a mammary mass, the most common initial clinical sign was inappetence. Histologic diagnoses were predominantly adenocarcinoma (n = 12), though two benign masses (mammary hyperplasia and a mammary cyst) and one squamous cell carcinoma were identified. Nine of 13 malignant tumors had metastasized to lymph nodes or viscera at the time of necropsy. Six lions with adenocarcinoma and two lions with benign mammary masses had received hormonal contraception, though little evidence of mammary lobular hyperplasia was seen in association with the adenocarcinomas. The most common concurrent disease processes found at necropsy were chronic urinary tract disease and other malignancies. These cases demonstrate that mammary malignancies occur in captive lions and frequently metastasize.

  2. CLINICOPATHOLOGIC FEATURES OF MAMMARY MASSES IN CAPTIVE LIONS (PANTHERA LEO).

    PubMed

    Sadler, Ryan A; Craig, Linden E; Ramsay, Edward C; Helmick, Kelly; Collins, Darin; Garner, Michael M

    2016-03-01

    A multi-institutional retrospective analysis of 330 pathology accessions from 285 different lions found 15 captive, female African lions (Panthera leo) with confirmed mammary masses. Aside from the presence of a mammary mass, the most common initial clinical sign was inappetence. Histologic diagnoses were predominantly adenocarcinoma (n = 12), though two benign masses (mammary hyperplasia and a mammary cyst) and one squamous cell carcinoma were identified. Nine of 13 malignant tumors had metastasized to lymph nodes or viscera at the time of necropsy. Six lions with adenocarcinoma and two lions with benign mammary masses had received hormonal contraception, though little evidence of mammary lobular hyperplasia was seen in association with the adenocarcinomas. The most common concurrent disease processes found at necropsy were chronic urinary tract disease and other malignancies. These cases demonstrate that mammary malignancies occur in captive lions and frequently metastasize. PMID:27010273

  3. Mouse Mammary Tumor Virus-Like Nucleotide Sequences in Canine and Feline Mammary Tumors▿

    PubMed Central

    Hsu, Wei-Li; Lin, Hsing-Yi; Chiou, Shyan-Song; Chang, Chao-Chin; Wang, Szu-Pong; Lin, Kuan-Hsun; Chulakasian, Songkhla; Wong, Min-Liang; Chang, Shih-Chieh

    2010-01-01

    Mouse mammary tumor virus (MMTV) has been speculated to be involved in human breast cancer. Companion animals, dogs, and cats with intimate human contacts may contribute to the transmission of MMTV between mouse and human. The aim of this study was to detect MMTV-like nucleotide sequences in canine and feline mammary tumors by nested PCR. Results showed that the presence of MMTV-like env and LTR sequences in canine malignant mammary tumors was 3.49% (3/86) and 18.60% (16/86), respectively. For feline malignant mammary tumors, the presence of both env and LTR sequences was found to be 22.22% (2/9). Nevertheless, the MMTV-like LTR and env sequences also were detected in normal mammary glands of dogs and cats. In comparisons of the MMTV-like DNA sequences of our findings to those of NIH 3T3 (MMTV-positive murine cell line) and human breast cancer cells, the sequence similarities ranged from 94 to 98%. Phylogenetic analysis revealed that intermixing among sequences identified from tissues of different hosts, i.e., mouse, dog, cat, and human, indicated the MMTV-like DNA existing in these hosts. Moreover, the env transcript was detected in 1 of the 19 MMTV-positive samples by reverse transcription-PCR. Taken together, our study provides evidence for the existence and expression of MMTV-like sequences in neoplastic and normal mammary glands of dogs and cats. PMID:20881168

  4. Ligand-independent canonical Wnt activity in canine mammary tumor cell lines associated with aberrant LEF1 expression.

    PubMed

    Gracanin, Ana; Timmermans-Sprang, Elpetra P M; van Wolferen, Monique E; Rao, Nagesha A S; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand-independent mechanisms.

  5. Ligand-Independent Canonical Wnt Activity in Canine Mammary Tumor Cell Lines Associated with Aberrant LEF1 Expression

    PubMed Central

    van Wolferen, Monique E.; Rao, Nagesha A. S.; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A.

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand–independent mechanisms. PMID:24887235

  6. Ligand-independent canonical Wnt activity in canine mammary tumor cell lines associated with aberrant LEF1 expression.

    PubMed

    Gracanin, Ana; Timmermans-Sprang, Elpetra P M; van Wolferen, Monique E; Rao, Nagesha A S; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand-independent mechanisms. PMID:24887235

  7. Mammary Stem Cells: A Clinician's View.

    PubMed

    Schneider, José

    2015-01-01

    Mammary stem cells were identified and isolated more than a decade ago and, although much remains to be learned, a lot has been revealed about their properties and behavior. Yet there is a gap between the newly acquired knowledge and its successful clinical application. This chapter presented a critical view from the perspective of a clinician. PMID:26040694

  8. Perinatal exposure to bisphenol a increases adult mammary gland progesterone response and cell number.

    PubMed

    Ayyanan, Ayyakkannu; Laribi, Ouahiba; Schuepbach-Mallepell, Sonia; Schrick, Christina; Gutierrez, Maria; Tanos, Tamara; Lefebvre, Gregory; Rougemont, Jacques; Yalcin-Ozuysal, Ozden; Brisken, Cathrin

    2011-11-01

    Bisphenol A [BPA, 2,2,-bis (hydroxyphenyl) propane] is one of the highest-volume chemicals produced worldwide. It is detected in body fluids of more than 90% of the human population. Originally synthesized as an estrogenic compound, it is currently utilized to manufacture food and beverage containers resulting in uptake with food and drinks. There is concern that exposure to low doses of BPA, defined as less than or equal to 5 mg/kg body weight /d, may have developmental effects on various hormone-responsive organs including the mammary gland. Here, we asked whether perinatal exposure to a range of low doses of BPA is sufficient to alter mammary gland hormone response later on in life, with a possible impact on breast cancer risk. To mimic human exposure, we added BPA to the drinking water of C57/Bl6 breeding pairs. Analysis of the mammary glands of their daughters at puberty showed that estrogen-dependent transcriptional events were perturbed and the number of terminal end buds, estrogen-induced proliferative structures, was altered in a dose-dependent fashion. Importantly, adult females showed an increase in mammary epithelial cell numbers comparable to that seen in females exposed to diethylbestrol, a compound exposure to which was previously linked to increased breast cancer risk. Molecularly, the mRNAs encoding Wnt-4 and receptor activator of nuclear factor κB ligand, two key mediators of hormone function implicated in control of mammary stem cell proliferation and carcinogenesis, showed increased induction by progesterone in the mammary tissue of exposed mice. Thus, perinatal exposure to environmentally relevant doses of BPA alters long-term hormone response that may increase the propensity to develop breast cancer.

  9. Wound healing-like immune program facilitates postpartum mammary gland involution and tumor progression

    PubMed Central

    Martinson, Holly A.; Jindal, Sonali; Durand-Rougely, Clarissa; Borges, Virginia F.; Schedin, Pepper

    2014-01-01

    Women diagnosed with breast cancer within 5 years postpartum have poor survival rates. The process of postpartum mammary gland involution, whereby the lactating gland remodels to its pre-pregnant state, promotes breast cancer progression in xenograft models. Macrophage influx occurs during mammary gland involution, implicating immune modulation in the promotion of postpartum breast cancer. Herein, we characterize the postpartum murine mammary gland and find an orchestrated influx of immune cells similar to that which occurs during wound healing. Further, the normal involuting gland may be in an immunosuppressed state as discerned by the transient presence of Foxp3+ regulatory T cells and IL-10+ macrophages with T cell suppressive function. To determine the influence of the postpartum immune microenvironment on mammary tumor promotion, we developed an immune-competent model. In this model, mammary tumors in the involution group are six-fold larger than nulliparous group tumors, have decreased CD4+ and CD8+ T cell infiltrates and contain a greater number of macrophages with the ability to inhibit T cell activation. Targeting involution with a neutralizing antibody against the immunosuppressive cytokine IL-10 reduces tumor growth in involution group mice but not in nulliparous mice, implicating the involution microenvironment as the primary target of αIL-10 treatment. Relevance to women is implicated, as we find post-lactational human breast tissue has transient high IL-10+ and Foxp3+ immune cell infiltrate. These data show an immune modulated microenvironment within the normal involuting mammary gland suggestive of immunosuppression, that when targeted reduces tumor promotion, revealing possible immune-based strategies for postpartum breast cancer. PMID:25187059

  10. Epidermal growth factor precursor in mouse lactating mammary gland alveolar cells

    SciTech Connect

    Brown, C.F.; Teng, C.T.; Pentecost, B.T.; DiAugustine, R.P. )

    1989-07-01

    Previous studies have demonstrated that high levels of epidermal growth factor (EGF) occur in human and rodent milk and that oral administration of this polypeptide stimulates rodent gastrointestinal development. It is not known whether EGF in milk originates from cells of the lactating mammary gland or is sequestered from an extramammary source. In the present study, prepro-EGF mRNA (approximately 4.7 kilobases) was detected in the CD-1 mouse mammary gland throughout the period of lactation; by comparison, negligible levels of this EGF transcript were found in the gland during pregnancy. Low levels of EGF immunoreactivity (4-5 ng/g wet wt tissue) were extracted from lactating (day 18) mammary glands with dilute acetic acid. Immunolocalization was evident with antisera to either EGF or two other regions of the EGF precursor in essentially all alveolar cells of the lactating gland. The most prominent staining with antiserum to EGF was observed along the luminal borders of cells; this pattern of cellular staining required proteolytic pretreatment of tissue sections. Western blot analyses of cell membranes isolated from the day 16 lactating mammary gland revealed an EGF-immunoreactive band at about 145K, which was equivalent in size to the EGF precursor found in mouse kidney cell membranes. Despite these findings, labeling of lactating mammary gland mince with L-(35S)methionine and cysteine for up to 4 h did not reveal any specific bands in immunoprecipitates. These cumulative findings suggest that the precursor form of EGF occurs in alveolar cells of lactating mammary gland and that this protein is translocated to the cell membrane.

  11. Wound healing-like immune program facilitates postpartum mammary gland involution and tumor progression.

    PubMed

    Martinson, Holly A; Jindal, Sonali; Durand-Rougely, Clarissa; Borges, Virginia F; Schedin, Pepper

    2015-04-15

    Women diagnosed with breast cancer within 5 years postpartum have poor survival rates. The process of postpartum mammary gland involution, whereby the lactating gland remodels to its prepregnant state, promotes breast cancer progression in xenograft models. Macrophage influx occurs during mammary gland involution, implicating immune modulation in the promotion of postpartum breast cancer. Herein, we characterize the postpartum murine mammary gland and find an orchestrated influx of immune cells similar to that which occurs during wound healing. Further, the normal involuting gland may be in an immunosuppressed state as discerned by the transient presence of Foxp3(+) regulatory T cells and IL-10(+) macrophages with T cell suppressive function. To determine the influence of the postpartum immune microenvironment on mammary tumor promotion, we developed an immune-competent model. In this model, mammary tumors in the involution group are sixfold larger than nulliparous group tumors, have decreased CD4(+) and CD8(+) T cell infiltrates and contain a greater number of macrophages with the ability to inhibit T cell activation. Targeting involution with a neutralizing antibody against the immunosuppressive cytokine IL-10 reduces tumor growth in involution group mice but not in nulliparous mice, implicating the involution microenvironment as the primary target of αIL-10 treatment. Relevance to women is implicated, as we find postlactational human breast tissue has transient high IL-10(+) and Foxp3(+) immune cell infiltrate. These data show an immune modulated microenvironment within the normal involuting mammary gland suggestive of immunosuppression, that when targeted reduces tumor promotion, revealing possible immune-based strategies for postpartum breast cancer.

  12. Histopathological and in vivo evidence of regucalcin as a protective molecule in mammary gland carcinogenesis

    SciTech Connect

    Marques, Ricardo; Vaz, Cátia V.; Maia, Cláudio J.; Gomes, Madalena; Gama, Adelina; Alves, Gilberto; Santos, Cecília R.; Schmitt, Fernando; Socorro, Sílvia

    2015-01-15

    Regucalcin (RGN) is a calcium-binding protein, which has been shown to be underexpressed in cancer cases. This study aimed to determine the association of RGN expression with clinicopathological parameters of human breast cancer. In addition, the role of RGN in malignancy of mammary gland using transgenic rats overexpressing the protein (Tg-RGN) was investigated. Wild-type (Wt) and Tg-RGN rats were treated with 7,12-dimethylbenz[α]anthracene (DMBA). Carcinogen-induced tumors were histologically classified and the Ki67 proliferation index was estimated. Immunohistochemistry analysis showed that RGN immunoreactivity was negatively correlated with the histological grade of breast infiltrating ductal carcinoma suggesting that progression of breast cancer is associated with loss of RGN. Tg-RGN rats displayed lower incidence of carcinogen-induced mammary gland tumors, as well as lower incidence of invasive forms. Moreover, higher proliferation was observed in non-invasive tumors of Wt animals comparatively with Tg-RGN. Overexpression of RGN was associated with diminished expression of cell-cycle inhibitors and increased expression of apoptosis inducers. Augmented activity of apoptosis effector caspase-3 was found in the mammary gland of Tg-RGN. RGN overexpression protected from carcinogen-induced mammary gland tumor development and was linked with reduced proliferation and increased apoptosis. These findings indicated the protective role of RGN in the carcinogenesis of mammary gland. - Highlights: • RGN immunoreactivity was negatively correlated with breast cancer differentiation. • Transgenic overexpression of RGN diminished incidence of carcinogen-induced tumors. • Transgenic overexpression of RGN restricted proliferation and fostered apoptosis. • RGN has a protective role in the carcinogenesis of mammary gland.

  13. Expression of class II beta-tubulin by proliferative myoepithelial cells in canine mammary mixed tumors.

    PubMed

    Arai, K; Nakano, H; Shibutani, M; Naoi, M; Matsuda, H

    2003-11-01

    Benign mammary mixed tumors in dogs resemble human salivary pleomorphic adenomas with regard to their histogenesis, including the occurrence of cartilaginous or bony metaplasia as well as the expression pattern of cytoskeletal proteins in proliferative myoepithelial cells. Recently, a monoclonal antibody specific for class II beta-tubulin has been developed. The epitope it recognizes was determined to be the heptapeptide Glu-Glu-Glu-Glu-Gly-Glu-Asp, which is the common sequence found among the canine, rat, mouse, and human class II beta-tubulin-specific regions. We carried out immunohistochemical studies on mammary mixed tumors obtained from three female dogs using this the monoclonal antibody. The antibody to class II beta-tubulin reacted intensely with proliferative myoepithelial cells in canine mammary mixed tumors, whereas staining was barely detectable in normal myoepithelial cells surrounding alveoli and alveolar ducts within the tumor and adjacent normal tissue. Proliferative myoepithelial cells also expressed vimentin, but alpha-smooth muscle actin (alphaSMA) staining was barely detectable. Immunoblot analysis showed that class II beta-tubulin and vimentin were expressed in myoepithelial cell lines prepared from the three mammary mixed tumors. On the other hand, only one cell line, which was negative for alphaSMA, produced cartilage-specific type II collagen. These results suggest that class II beta-tubulin could be a new molecular marker of proliferating myoepithelial cells in canine mammary mixed tumors and that differential expression of cytoskeletal components is associated with cartilaginous metaplasia of proliferative myoepithelial cells in mixed mammary tumors.

  14. In vitro differentiation of a cloned bovine mammary epithelial cell.

    PubMed

    Rose, Michael T; Aso, Hisashi; Yonekura, Shinichi; Komatsu, Tokushi; Hagino, Akihiko; Ozutsumi, Kyouhei; Obara, Yoshiaki

    2002-08-01

    The aim of the study was to establish in vitro a bovine mammary epithelial cell (MEC) clone, able to respond to mitogenic growth factors and to lactogenic hormones. Mammary tissue from a 200-d pregnant Holstein cow was used as a source of MEC, from which a clone was established through a process of limiting dilution. When plated on plastic, the cells assumed a monolayer, cobblestone, epithelial-like morphology, with close contact between cells. Inclusion of IGF-1 and EGF in the media significantly increased the number of cells 5 d after plating. All cells stained strongly for cytokeratin and moderately for vimentin at young and old passage stages, indicating the epithelial nature of this cell clone. When the cells were plated at a high density on a thin layer of a commercial extracellular matrix preparation (Matrigel), lobular, alveoli-like structures developed within approximately 5 d, with a clearly visible lumen. When cells were plated onto Matrigel in differentiation media (containing lactogenic hormones), detectable quantities of alpha-casein were present in the media and particularly on the lumen side of the structures. Omission of one of the lactogenic hormones (insulin, prolactin or hydrocortisone) reduced alpha-casein release to the limit of detection of the assay used. Lactoferrin was also produced when the cells were plated on Matrigel, again principally on the lumen side of the lobules, though this was independent of the lactogenic hormones. By passage 40, the cells had senesced, and it was not possible to induce alpha-casein or lactoferrin production. This study notes the establishment of a functional bovine mammary epithelial cell clone, which is responsive to mitogenic and lactogenic hormones and an extracellular matrix.

  15. Xanthosine administration does not affect the proportion of epithelial stem cells in bovine mammary tissue, but has a latent negative effect on cell proliferation

    SciTech Connect

    Rauner, Gat; Barash, Itamar

    2014-10-15

    The challenge in manipulating the proportion of somatic stem cells lies in having to override tissue homeostasis. Xanthosine infusion via the teat canal has been reported to augment the number of label-retaining cells in the mammary gland of 3-month-old bovine calves. To further delineate xanthosine's effect on defined stem cells in the mammary gland of heifers—which are candidates for increased prospective milk production following such manipulation—bovine mammary parenchymal tissue was transplanted and integrated into the cleared mammary fat pad of immunodeficient mice. Xanthosine administration for 14 days did not affect the number of label-retaining cells after 10- and 11-week chases. No change in stem cell proportion, analyzed according to CD49f and CD24 expression, was noted. Clone formation and propagation rate of cultured cells, as well as expression of stem cell markers, were also unaffected. In contrast, a latent 50% decrease in bovine mammary cell proliferation rate was observed 11 weeks after xanthosine administration. Tumor development in mice was also limited by xanthosine administration. These effects may have resulted from an initial decrease in expression of the rate-limiting enzyme in guanine synthesis, IMPDH. The data indicate that caution should be exerted when considering xanthosine for stem cell manipulation. - Highlights: • Novel “bovinized“ mouse model for exogenous effects on bovine mammary gland. • Xanthosine did not affect stem cell number/function in bovine mammary gland. • Xanthosine caused an immediate decrease in IMPDH expression in bovine mammary gland. • Xanthosine had latent negative effect on cell proliferation in bovine mammary gland. • Xanthosine administration limited mammary tumor growth.

  16. Radiogenic neoplasia in thyroid and mammary clonogens

    SciTech Connect

    Clifton, K.H.

    1992-05-20

    We have developed rat thyroid and mammary clonogen transplantation systems for the study of radiogenic cancer induction at the target cell level in vivo. The epithelial cell populations of both glands contain small subpopulations of cells which are capable of giving rise to monoclonal glandular structures when transplanted and stimulated with appropriate hormones. Previous results indicated that these clonogens are the precursor cells of radiogenic cancer, and that initiation, is common event at the clonegenic cell level. Detailed information on the physiologic control of clonogen proliferation, differentiation, and total numbers is thus essential to an understanding of the carcinogenic process. We report here studies on investigations on the relationships between grafted thyroid cell number and the rapidity and degree of reestablishment of the thyroid-hypothalamus-pituitary feedback axis in thyroidectomized rats maintained on a normal diet or an iodine deficient diet; studies of the persistence of, and the differentiation potential and functional characteristics of, the TSH-(thyrotropin-) responsive sub- population of clonogens during goitrogenesis, the plateau-phase of goiter growth, and goiter involution; studies of changes in the size of the clonogen sub-population during goitrogenesis, goiter involution and the response to goitrogen rechallenge; and a large carcinogenesis experiment on the nature of the grafted thyroid cell number-dependent suppression of promotion/progression to neoplasia in grafts of radiation-initiated thyroid cells. Data from these studies will be used in the design of future carcinogenesis experiments on neoplastic initiation by high and low LET radiations and on cell interactions during the neoplastic process.

  17. [Prognostic significance of p53 expression in patients with mammary gland cancer].

    PubMed

    Shchurov, N F; Pogorelaia, T Iu; Zaplatina, S V

    2013-07-01

    Prognostic significance of p53 expression in tumoral cells was studied in patients, suffering mammary gland cancer (MGC). The higher p53 mutative type expression in the tumor, the more aggressive is MGC development, the indices of general and disease-free survival are poorer, so prognosis is poorer as well.

  18. Generation and characterization of a breast carcinoma model by PyMT overexpression in mammary epithelial cells of tree shrew, an animal close to primates in evolution.

    PubMed

    Ge, Guang-Zhe; Xia, Hou-Jun; He, Bao-Li; Zhang, Hai-Lin; Liu, Wen-Jing; Shao, Ming; Wang, Chun-Yan; Xiao, Ji; Ge, Fei; Li, Fu-Bing; Li, Yi; Chen, Ceshi

    2016-02-01

    The tree shrew is becoming an attractive experimental animal model for human breast cancer owing to a closer relationship to primates/humans than rodents. Tree shrews are superior to classical primates because tree shrew are easier to manipulate, maintain and propagate. It is required to establish a high-efficiency tree shrew breast cancer model for etiological research and drug assessment. Our previous studies suggest that 7,12-dimethylbenz(a)anthracene (DMBA) and medroxyprogesterone acetate (MPA) induce breast tumors in tree shrews with a low frequency (<50%) and long latency (∼ 7-month), making these methods less than ideal. We induced mammary tumors in tree shrew (Tupaia belangeri chinensis) by injection of lentivirus expressing the PyMT oncogene into mammary ducts of 22 animals. Most tree shrews developed mammary tumors with a latency of about three weeks, and by 7 weeks all injected tree shrews had developed mammary tumors. Among these, papillary carcinoma is the predominant tumor type. One case showed lymph node and lung metastasis. Interestingly, the expression levels of phosphorylated AKT, ERK and STAT3 were elevated in 41-68% of PyMT-induced mammary tumors, but not all tumors. Finally, we observed that the growth of PyMT-induced tree shrew mammary tumors was significantly inhibited by Cisplatin and Epidoxorubicin. PyMT-induced tree shrew mammary tumor model may be suitable for further breast cancer research and drug development, due to its high efficiency and short latency.

  19. Influence of dietary menhaden oil on 7,12-dimethylbenzanthracene induced mammary tumorigenesis in rats

    SciTech Connect

    O'Connor, T.P.; Peterson, F.; Campbell, T.C.

    1986-03-05

    The effect of dietary menhaden oil on 7,12-dimethylbenzanthracene (DMBA) induced mammary tumorigenesis was examined in female Sprague-Dawley rats. Rats were obtained at age 28 days and acclimated until age 50 days when they received a single i.g. dose of 5 mg DMBA dissolved in 1 ml corn oil. Rats were then randomly assigned to one of four treatment groups with 25 rats per group. One group was fed a diet based on fish protein (freeze-dried cod) and corn oil (F/C). The second group received a diet based on fish protein and menhaden oil (F/M). The third group received a casein based diet with corn oil as the lipid source (C/C). The fourth group was fed a casein based diet with menhaden oil as the lipid source (C/M). Both the protein and lipid sources were fed at a level of 20% by weight of the diets. Rats were palpated weekly to check for mammary tumor development and the experiment was terminated 24 weeks after DMBA administration. Rats fed menhaden oil as a lipid source (F/M and C/M groups) developed significantly fewer mammary tumors than animals on the corn oil based diets (F/C and C/C groups, respectively). Thus, menhaden oil, rich in omega-3 fatty acids, significantly inhibited the development of DMBA induced mammary tumors in this experiment.

  20. Mammary gland neoplasia in long-term rodent studies.

    PubMed Central

    Russo, I H; Russo, J

    1996-01-01

    Breast cancer, the most frequent spontaneous malignancy diagnosed in women in the western world, is continuously increasing in incidence in industrialized nations. Although breast cancer develops in women as the result of a combination of external and endogenous factors such as exposure to ionizing radiation, diet, socioeconomic status, and endocrinologic, familial, or genetic factors, no specific etiologic agent(s) or the mechanisms responsible of the disease has been identified as yet. Thus, experimental models that exhibit the same complex interactions are needed for testing various mechanisms and for assessing the carcinogenic potential of given chemicals. Rodent mammary carcinomas represent such a model to a great extent because, in these species, mammary cancer is a multistep complex process that can be induced by either chemicals, radiation, viruses, or genetic factors. Long-term studies in rodent models have been particularly useful for dissecting the initiation, promotion, and progression steps of carcinogenesis. The susceptibility of the rodent mammary gland to develop neoplasms has made this organ a unique target for testing the carcinogenic potential of specific genotoxic chemicals and environmental agents. Mammary tumors induced by indirect- or direct-acting carcinogens such as 7, 12-dimethlbenz(a)anthracene or N-methyl-N-nitrosourea are, in general, hormone dependent adenocarcinomas whose incidence, number of tumors per animal, tumor latency, and tumor type are influenced by the age, reproductive history, and endocarinologic milieu of the host at the time of carcinogen exposure. Rodent models are informative in the absence of human data. They have provided valuable information on the dose and route of administration to be used and optimal host conditions for eliciting maximal tumorigenic response. Studies of the influence of normal gland development on the pathogenesis of chemically induced mammary carcinomas have clarified the role of differentiation

  1. GH-producing mammary tumors in two dogs with acromegaly.

    PubMed

    Murai, Atsuko; Nishii, Naohito; Morita, Takehito; Yuki, Masashi

    2012-06-01

    Two intact female dogs were admitted for growing mammary tumors. They had symptoms of acromegaly including weight gain, enlargement of the head, excessive skin folds, and inspiratory stridor. Serum concentrations of growth hormone (GH), insulin-like growth factor-I (IGF-I), and insulin were elevated in the two cases. From these findings, both dogs were diagnosed with acromegaly. In case 1, the GH, IGF-I, and insulin levels subsided after removal of the focal benign mammary tumors and ovariohysterectomy. In case 2, those levels subsided after removal of only focal mammary carcinoma. In both cases, immunohistochemical investigations for GH were positive in the mammary tumor cells but not in the normal mammary glands. We concluded that GH-producing mammary tumors caused the present acromegaly.

  2. Dmp1α Inhibits HER2/neu-Induced Mammary Tumorigenesis

    PubMed Central

    Fry, Elizabeth A.; Taneja, Pankaj; Maglic, Dejan; Zhu, Sinan; Sui, Guangchao; Inoue, Kazushi

    2013-01-01

    Our recent study shows a pivotal role of Dmp1 in quenching hyperproliferative signals from HER2 to the Arf-p53 pathway as a safety mechanism to prevent breast carcinogenesis. To directly demonstrate the role of Dmp1 in preventing HER2/neu-driven oncogenic transformation, we established Flag-Dmp1α transgenic mice (MDTG) under the control of the mouse mammary tumor virus (MMTV) promoter. The mice were viable but exhibited poorly developed mammary glands with markedly reduced milk production; thus more than half of parous females were unable to support the lives of new born pups. The mammary glands of the MDTG mice had very low Ki-67 expression but high levels of Arf, Ink4a, p53, and p21Cip1, markers of senescence and accelerated aging. In all strains of generated MDTG;neu mice, tumor development was significantly delayed with decreased tumor weight. Tumors from MDTG;neu mice expressed Flag-Dmp1α and Ki-67 in a mutually exclusive fashion indicating that transgenic Dmp1α prevented tumor growth in vivo. Genomic DNA analyses showed that the Dmp1α transgene was partially lost in half of the MDTG;neu tumors, and Western blot analyses showed Dmp1α protein downregulation in 80% of the cases. Our data demonstrate critical roles of Dmp1 in preventing mammary tumorigenesis and raise the possibility of treating breast cancer by restoring Dmp1α expression. PMID:24205004

  3. Mammary tumor growth and metastasis are reduced in c-Kit mutant Sash mice.

    PubMed

    He, Licai; Zhu, Zhenfeng; Chen, Shang; Wang, Yongping; Gu, Haihua

    2016-06-01

    Besides its well-known function in allergic response, mast cell, one of the key immune cells present in tumor microenvironment, plays important roles in cancer progression. However, the functional role of mast cells in breast cancer development and metastasis is not well understood. To test the involvement of mast cells in breast cancer, we examined the effects of loss of mast cells on mammary tumor development by crossing the well-known mast cell deficient mouse strain sash (Kit(W-sh/W-sh) ) with the mammary tumor transgenic mouse strain MMTV-Polyoma Middle T antigen (PyMT). Although mammary tumor onset was not affected in the absence of mast cells, mammary growth and metastasis were reduced in PyMT/Kit(W-sh/W-sh) mice compared with PyMT/wild-type mice (WT). Histological and immunofluorescent analyses showed that tumors from PyMT/Kit(W-sh/W-sh) mice showed largely differentiated morphology with reduced angiogenesis compared with MMTV-PyMT/WT mice. Our results suggest that mast cells may promote breast cancer growth and metastasis. Agents that can block mast cells growth are potential new therapies to treat metastatic breast cancer. PMID:26992445

  4. RANKL/RANK control Brca1 mutation-driven mammary tumors.

    PubMed

    Sigl, Verena; Owusu-Boaitey, Kwadwo; Joshi, Purna A; Kavirayani, Anoop; Wirnsberger, Gerald; Novatchkova, Maria; Kozieradzki, Ivona; Schramek, Daniel; Edokobi, Nnamdi; Hersl, Jerome; Sampson, Aishia; Odai-Afotey, Ashley; Lazaro, Conxi; Gonzalez-Suarez, Eva; Pujana, Miguel A; Cimba, For; Heyn, Holger; Vidal, Enrique; Cruickshank, Jennifer; Berman, Hal; Sarao, Renu; Ticevic, Melita; Uribesalgo, Iris; Tortola, Luigi; Rao, Shuan; Tan, Yen; Pfeiler, Georg; Lee, Eva Yhp; Bago-Horvath, Zsuzsanna; Kenner, Lukas; Popper, Helmuth; Singer, Christian; Khokha, Rama; Jones, Laundette P; Penninger, Josef M

    2016-07-01

    Breast cancer is the most common female cancer, affecting approximately one in eight women during their life-time. Besides environmental triggers and hormones, inherited mutations in the breast cancer 1 (BRCA1) or BRCA2 genes markedly increase the risk for the development of breast cancer. Here, using two different mouse models, we show that genetic inactivation of the key osteoclast differentiation factor RANK in the mammary epithelium markedly delayed onset, reduced incidence, and attenuated progression of Brca1;p53 mutation-driven mammary cancer. Long-term pharmacological inhibition of the RANK ligand RANKL in mice abolished the occurrence of Brca1 mutation-driven pre-neoplastic lesions. Mechanistically, genetic inactivation of Rank or RANKL/RANK blockade impaired proliferation and expansion of both murine Brca1;p53 mutant mammary stem cells and mammary progenitors from human BRCA1 mutation carriers. In addition, genome variations within the RANK locus were significantly associated with risk of developing breast cancer in women with BRCA1 mutations. Thus, RANKL/RANK control progenitor cell expansion and tumorigenesis in inherited breast cancer. These results present a viable strategy for the possible prevention of breast cancer in BRCA1 mutant patients. PMID:27241552

  5. Breast cancer protein PS2 synthesis in mammary gland of transgenic mice and secretion into milk.

    PubMed

    Tomasetto, C; Wolf, C; Rio, M C; Mehtali, M; LeMeur, M; Gerlinger, P; Chambon, P; Lathe, R

    1989-10-01

    PS2, a small estrogen-inducible secretory polypeptide with structural analogies to a growth factor, is produced by approximately 50% of human breast tumors. The function of PS2 is, however, unknown. To determine whether PS2 may play an autocrine role in the development of mammary tumors we constructed transgenic mice bearing fusion constructs designed to direct the expression of human PS2 in the lactating mammary gland under the control of the whey acidic protein (WAP) promoter. Mouse lines bearing the genomic PS2 gene under the control of the WAP promoter region (WAP-PS2-2) failed to express the transgene. However, mice harboring the fusion construct WAP-PS2-1, in which the PS2 coding sequence is inserted into the 5' untranslated region of the complete WAP gene, were observed to express the transgene. Expression was restricted to the secretory epithelium of the mammary gland during lactation, and PS2 protein was secreted into the milk. Nevertheless, no mammary gland dysplasia was observed, and PS2 expression had no discernable effect upon the physiology and/or development of the suckling young or the transgenic mother. PMID:2481815

  6. RANKL/RANK control Brca1 mutation-driven mammary tumors.

    PubMed

    Sigl, Verena; Owusu-Boaitey, Kwadwo; Joshi, Purna A; Kavirayani, Anoop; Wirnsberger, Gerald; Novatchkova, Maria; Kozieradzki, Ivona; Schramek, Daniel; Edokobi, Nnamdi; Hersl, Jerome; Sampson, Aishia; Odai-Afotey, Ashley; Lazaro, Conxi; Gonzalez-Suarez, Eva; Pujana, Miguel A; Cimba, For; Heyn, Holger; Vidal, Enrique; Cruickshank, Jennifer; Berman, Hal; Sarao, Renu; Ticevic, Melita; Uribesalgo, Iris; Tortola, Luigi; Rao, Shuan; Tan, Yen; Pfeiler, Georg; Lee, Eva Yhp; Bago-Horvath, Zsuzsanna; Kenner, Lukas; Popper, Helmuth; Singer, Christian; Khokha, Rama; Jones, Laundette P; Penninger, Josef M

    2016-07-01

    Breast cancer is the most common female cancer, affecting approximately one in eight women during their life-time. Besides environmental triggers and hormones, inherited mutations in the breast cancer 1 (BRCA1) or BRCA2 genes markedly increase the risk for the development of breast cancer. Here, using two different mouse models, we show that genetic inactivation of the key osteoclast differentiation factor RANK in the mammary epithelium markedly delayed onset, reduced incidence, and attenuated progression of Brca1;p53 mutation-driven mammary cancer. Long-term pharmacological inhibition of the RANK ligand RANKL in mice abolished the occurrence of Brca1 mutation-driven pre-neoplastic lesions. Mechanistically, genetic inactivation of Rank or RANKL/RANK blockade impaired proliferation and expansion of both murine Brca1;p53 mutant mammary stem cells and mammary progenitors from human BRCA1 mutation carriers. In addition, genome variations within the RANK locus were significantly associated with risk of developing breast cancer in women with BRCA1 mutations. Thus, RANKL/RANK control progenitor cell expansion and tumorigenesis in inherited breast cancer. These results present a viable strategy for the possible prevention of breast cancer in BRCA1 mutant patients.

  7. Oncogenic AKT1(E17K) mutation induces mammary hyperplasia but prevents HER2-driven tumorigenesis

    PubMed Central

    Mancini, Maria L.; Lien, Evan C.; Toker, Alex

    2016-01-01

    One of the most frequently deregulated signaling pathways in breast cancer is the PI 3-K/Akt cascade. Genetic lesions are commonly found in PIK3CA, PTEN, and AKT, which lead to excessive and constitutive activation of Akt and downstream signaling that results in uncontrolled proliferation and increased cellular survival. One such genetic lesion is the somatic AKT1(E17K) mutation, which has been identified in 4-8% of breast cancer patients. To determine how this mutation contributes to mammary tumorigenesis, we constructed a genetically engineered mouse model that conditionally expresses human AKT1(E17K) in the mammary epithelium. Although AKT1(E17K) is only weakly constitutively active and does not promote proliferation in vitro, it is capable of escaping negative feedback inhibition to exhibit sustained signaling dynamics in vitro. Consistently, both virgin and multiparous AKT1(E17K) mice develop mammary gland hyperplasia that do not progress to carcinoma. This hyperplasia is accompanied by increased estrogen receptor expression, although exposure of the mice to estrogen does not promote tumor development. Moreover, AKT1(E17K) prevents HER2-driven mammary tumor formation, in part through negative feedback inhibition of RTK signaling. Analysis of TCGA breast cancer data revealed that the mRNA expression, total protein levels, and phosphorylation of various RTKs are decreased in human tumors harboring AKT1(E17K). PMID:27004402

  8. Cox-2 levels in canine mammary tumors, including inflammatory mammary carcinoma: clinicopathological features and prognostic significance.

    PubMed

    Queiroga, Felisbina Luisa; Perez-Alenza, Maria Dolores; Silvan, Gema; Peña, Laura; Lopes, Carlos; Illera, Juan Carlos

    2005-01-01

    Cyclo-oxygenase (Cox-2) plays an important role in mammary carcinogenesis, nevertheless, its role in canine mammary tumors, and particularly in inflammatory mammary carcinoma (IMC), is unknown. Tumor Cox-2 levels were analyzed by enzyme immunoassay, in post-surgical tumor homogenates of 129 mammary tumors (62 dysplasias and benign tumors, 57 malignant non-IMC and 10 IMC) from 57 female dogs. The highest Cox-2 values were detected in the IMC group. In non-IMC malignant tumors, high values of Cox-2 were related to skin ulceration (p < 0.001) and tumor size (p < 0.001). The follow-up study revealed that high Cox-2 levels were related with recurrence (p = 0.002), metastases (p < 0.001), disease-free survival (p < 0.001) and overall survival (p < 0.001). This study demonstrates an association between intra-tumor Cox-2 levels and poor prognosis. The high levels found in IMC cases could indicate a special role of Cox-2 in the inflammatory phenotype and open the possibility of additional new therapeutic approaches in this special type of mammary cancer in humans and dogs.

  9. Expression and significance of CHIP in canine mammary gland tumors.

    PubMed

    Wang, Huanan; Yang, Xu; Jin, Yipeng; Pei, Shimin; Zhang, Di; Ma, Wen; Huang, Jian; Qiu, Hengbin; Zhang, Xinke; Jiang, Qiuyue; Sun, Weidong; Zhang, Hong; Lin, Degui

    2015-11-01

    CHIP (Carboxy terminus of Hsc70 Interacting Protein) is an E3 ubiquitin ligase that can induce ubiquitination and degradation of several oncogenic proteins. The expression of CHIP is frequently lower in human breast cancer than in normal breast tissue. However, the expression and role of CHIP in the canine mammary gland tumor (CMGT) remain unclear. We investigated the potential correlation between CHIP expression and mammary gland tumor prognosis in female dogs. CHIP expression was measured in 54 dogs by immunohistochemistry and real-time RT-PCR. CHIP protein expression was significantly correlated with the histopathological diagnosis, outcome of disease and tumor classification. The transcriptional level of CHIP was significantly higher in normal tissues (P=0.001) and benign tumors (P=0.009) than it in malignant tumors. CHIP protein expression was significantly correlated with the transcriptional level of CHIP (P=0.0102). The log-rank test survival curves indicated that patients with low expression of CHIP had shorter overall periods of survival than those with higher CHIP protein expression (P=0.050). Our data suggest that CHIP may play an important role in the formation and development of CMGTs and serve as a valuable prognostic marker and potential target for genetic therapy.

  10. Molecular biological aspects on canine and human mammary tumors.

    PubMed

    Rivera, P; von Euler, H

    2011-01-01

    The high incidence of mammary tumor disease reported in certain canine breeds suggests a significant genetic component, as has already been described in human familial breast cancer-in BRCA1- and BRCA2-associated breast cancer in particular. The identification of genetic risk factors is critical to improvements in the prevention, diagnosis, and treatment of these tumors. In recent years, there has been significant progress in developing the tools and reagents necessary to analyze the canine genome. This work has culminated in a high-quality draft genome sequence, as well as a single-nucleotide polymorphism map and single-nucleotide polymorphism arrays for genomewide association analysis. These tools provide an unprecedented opportunity to characterize the genetic influences in canine diseases such as cancer, eventually allowing for exploration of more effective therapies. Given the high homology between the canine genome sequence and its human counterpart--as well as the many similarities regarding the morphology, biological behavior, and clinical course of mammary tumors in both species--the dog has proven to be an excellent comparative model. This review highlights the comparative aspects regarding certain areas within molecular biology, and it discusses future perspectives. The findings in larger genomewide association analyses and cDNA expression arrays are described, and the BRCA1/BRCA2 complex is compared in detail between the 2 species. PMID:21147766

  11. Immunohistochemical vascular factor expression in canine inflammatory mammary carcinoma.

    PubMed

    Camacho, L; Peña, L; Gil, A González; Martín-Ruiz, A; Dunner, S; Illera, J C

    2014-07-01

    Human inflammatory breast carcinoma (IBC) and canine inflammatory mammary carcinoma (IMC) are considered the most malignant types of breast cancer. IMC has similar characteristics to IBC; hence, IMC has been suggested as a model to study the human disease. To compare the angiogenic and angioinvasive features of IMC with non-IMC, 3 canine mammary tumor xenograft models in female SCID mice were developed: IMC, comedocarcinoma, and osteosarcoma. Histopathological and immunohistochemical characterization of both primary canine tumors and xenografts using cellular markers pancytokeratin, cytokeratin 14, vimentin, and α-smooth muscle actin and vascular factors (VEGF-A, VEGF-D, VEGFR-3, and COX-2) was performed. Tumor cell proliferation index was measured by the Ki-67 marker. The xenograft models reproduced histological features found in the primary canine tumor and preserved the original immunophenotype. IMC xenografts showed a high invasive character with tumor emboli in the dermis, edema, and occasional observations of ulceration. In addition, compared with osteosarcoma and comedocarcinoma, the IMC model showed the highest vascular factor expression associated with a high proliferation index. Likewise, IMC xenografts showed higher COX-2 expression associated with VEGF-D and VEGFR-3, as well as a higher presence of dermal lymphatic tumor emboli, suggesting COX-2 participation in IMC lymphangiogenesis. These results provide additional evidence to consider vascular factors, their receptors, and COX-2 as therapeutic targets for IBC.

  12. Adipose and mammary epithelial tissue engineering.

    PubMed

    Zhu, Wenting; Nelson, Celeste M

    2013-01-01

    Breast reconstruction is a type of surgery for women who have had a mastectomy, and involves using autologous tissue or prosthetic material to construct a natural-looking breast. Adipose tissue is the major contributor to the volume of the breast, whereas epithelial cells comprise the functional unit of the mammary gland. Adipose-derived stem cells (ASCs) can differentiate into both adipocytes and epithelial cells and can be acquired from autologous sources. ASCs are therefore an attractive candidate for clinical applications to repair or regenerate the breast. Here we review the current state of adipose tissue engineering methods, including the biomaterials used for adipose tissue engineering and the application of these techniques for mammary epithelial tissue engineering. Adipose tissue engineering combined with microfabrication approaches to engineer the epithelium represents a promising avenue to replicate the native structure of the breast.

  13. Adipose and mammary epithelial tissue engineering

    PubMed Central

    Zhu, Wenting; Nelson, Celeste M.

    2013-01-01

    Breast reconstruction is a type of surgery for women who have had a mastectomy, and involves using autologous tissue or prosthetic material to construct a natural-looking breast. Adipose tissue is the major contributor to the volume of the breast, whereas epithelial cells comprise the functional unit of the mammary gland. Adipose-derived stem cells (ASCs) can differentiate into both adipocytes and epithelial cells and can be acquired from autologous sources. ASCs are therefore an attractive candidate for clinical applications to repair or regenerate the breast. Here we review the current state of adipose tissue engineering methods, including the biomaterials used for adipose tissue engineering and the application of these techniques for mammary epithelial tissue engineering. Adipose tissue engineering combined with microfabrication approaches to engineer the epithelium represents a promising avenue to replicate the native structure of the breast. PMID:23628872

  14. Bovine mammary stem cells: new perspective for dairy science.

    PubMed

    Martignani, E; Cravero, D; Miretti, S; Accornero, P; Baratta, M

    2014-01-01

    Mammary stem cells provide opportunities for the cyclic remodelling of the bovine mammary gland. Therefore, understanding the character and regulation of mammary stem cells is important for increasing animal health and productivity. The exciting possibility that stem cell expansion can influence milk production is currently being investigated by several researchers. In fact, appropriate regulation of mammary stem cells could hopefully benefit milk yield, persistency of lactation, dry period management and tissue repair. Accordingly, we and others have attempted to characterize and regulate the function of bovine mammary stem cells. However, research on mammary stem cells requires tissue biopsies, which represents a limitation for the management of animal welfare. Interestingly, different studies recently reported the identification of putative mammary stem cells in human breast milk. The possible identification of primitive cell types within cow's milk may provide a non-invasive source of relevant mammary cells for a wide range of applications. In this review, we have summarized the main achievements in this field for dairy cow science and described the interesting perspectives open to manipulate milk persistency during lactation and to cope with oxidative stress during the transition period by regulating mammary stem cells.

  15. Absence of canine papillomavirus sequences in canine mammary tumours.

    PubMed

    Sardon, D; Blundell, R; Burrai, G P; Alberti, A; Tore, G; Passino, E Sanna; Antuofermo, E

    2015-01-01

    Human papillomaviruses (PVs) are found in human breast cancer tissue; however, it remains controversial as to whether these viruses play a role in the aetiology of this tumour. There has been minimal study of whether PVs are found in normal or abnormal mammary glands of animals. The present study investigated whether a PV sequence could be found in the mammary glands of 33 female dogs by rolling circle amplification and polymerase chain reaction. No PV DNA was found in normal or neoplastic canine mammary tissues, suggesting that canine PVs are probably not involved in the pathogenesis of canine mammary neoplasia. PMID:25435511

  16. Establishment of mammary gland model in vitro: culture and evaluation of a yak mammary epithelial cell line.

    PubMed

    Fu, Mei; Chen, Yabing; Xiong, Xianrong; Lan, Daoliang; Li, Jian

    2014-01-01

    This study aimed to establish yak mammary epithelial cells (YMECs) for an in vitro model of yak mammary gland biology. The primary culture of YMECs was obtained from mammary gland tissues of lactating yak and then characterized using immunocytochemistry, RT-PCR, and western blot analysis. Whether foreign genes could be transfected into the YMECs were examined by transfecting the EGFP gene into the cells. Finally, the effect of Staphylococcus aureus infection on YMECs was determined. The established YMECs retained the mammary epithelial cell characteristics. A spontaneously immortalized yak mammary epithelial cell line was established and could be continuously subcultured for more than 60 passages without senescence. The EGFP gene was successfully transferred into the YMECs, and the transfected cells could be maintained for a long duration in the culture by continuous subculturing. The cells expressed more antimicrobial peptides upon S.aureus invasion. Therefore, the established cell line could be considered a model system to understand yak mammary gland biology.

  17. Mammary stem cells: expansion and animal productivity

    PubMed Central

    2014-01-01

    Identification and characterization of mammary stem cells and progenitor cells from dairy animals is important in the understanding of mammogenesis, tissue turnover, lactation persistency and regenerative therapy. It has been realized by many investigators that altered lactation, long dry periods (non-milking period between two consecutive lactation cycles), abrupt cessation of lactation (common in water buffaloes) and disease conditions like mastitis, greatly reduce milk yield thus render huge financial losses within the dairy sector. Cellular manipulation of specialized cell types within the mammary gland, called mammary stem cells (MaSCs)/progenitor cells, might provide potential solutions to these problems and may improve milk production. In addition, MaSCs/progenitor cells could be used in regenerative therapy against tissue damage caused by mastitis. This review discusses methods of MaSC/progenitor cell manipulation and their mechanisms in bovine and caprine animals. Author believes that intervention of MaSCs/progenitor cells could lessen the huge financial losses to the dairy industry globally. PMID:25057352

  18. PKA signaling drives mammary tumorigenesis through Src.

    PubMed

    Beristain, A G; Molyneux, S D; Joshi, P A; Pomroy, N C; Di Grappa, M A; Chang, M C; Kirschner, L S; Privé, G G; Pujana, M A; Khokha, R

    2015-02-26

    Protein kinase A (PKA) hyperactivation causes hereditary endocrine neoplasias; however, its role in sporadic epithelial cancers is unknown. Here, we show that heightened PKA activity in the mammary epithelium generates tumors. Mammary-restricted biallelic ablation of Prkar1a, which encodes for the critical type-I PKA regulatory subunit, induced spontaneous breast tumors characterized by enhanced type-II PKA activity. Downstream of this, Src phosphorylation occurs at residues serine-17 and tyrosine-416 and mammary cell transformation is driven through a mechanism involving Src signaling. The phenotypic consequences of these alterations consisted of increased cell proliferation and, accordingly, expansion of both luminal and basal epithelial cell populations. In human breast cancer, low PRKAR1A/high SRC expression defines basal-like and HER2 breast tumors associated with poor clinical outcome. Together, the results of this study define a novel molecular mechanism altered in breast carcinogenesis and highlight the potential strategy of inhibiting SRC signaling in treating this cancer subtype in humans. PMID:24662820

  19. Oxytocin binding sites in bovine mammary tissue

    SciTech Connect

    Zhao, Xin.

    1989-01-01

    Oxytocin binding sites were identified and characterized in bovine mammary tissue. ({sup 3}H)-oxytocin binding reached equilibrium by 50 min at 20{degree}C and by 8 hr at 4{degree}C. The half-time of displacement at 20{degree}C was approximately 1 hr. Thyrotropin releasing hormone, adrenocorticotropin, angiotensin I, angiotensin II, pentagastrin, bradykinin, xenopsin and L-valyl-histidyl-L-leucyl-L-threonyl-L-prolyl-L-valyl-L-glutamyl-L-lysine were not competitive. In the presence of 10 nM LiCl, addition of oxytocin to dispersed bovine mammary cells, in which phosphatidylinositol was pre-labelled, caused a time and dose-dependent increase in radioactive inositiol monophosphate incorporation. The possibility that there are distinct vasopressin receptors in bovine mammary tissue was investigated. ({sup 3}H)-vasopressin binding reached equilibrium by 40 min at 20{degree}. The half-time of displacement at 20{degree}C was approximately 1 hr. The ability of the peptides to inhibit ({sup 3}H)-vasopressin binding was: (Thr{sup 4},Gly{sup 7})-oxytocin > Arg{sup 8}-vasopressin > (lys{sup 8})-vasopressin > (Deamino{sup 1},D-arg{sup 8})-vasopressin > oxytocin > d (CH{sub 2}){sub 5}Tyr(Me)AVP.

  20. Mammary stem cells: expansion and animal productivity.

    PubMed

    Choudhary, Ratan K

    2014-01-01

    Identification and characterization of mammary stem cells and progenitor cells from dairy animals is important in the understanding of mammogenesis, tissue turnover, lactation persistency and regenerative therapy. It has been realized by many investigators that altered lactation, long dry periods (non-milking period between two consecutive lactation cycles), abrupt cessation of lactation (common in water buffaloes) and disease conditions like mastitis, greatly reduce milk yield thus render huge financial losses within the dairy sector. Cellular manipulation of specialized cell types within the mammary gland, called mammary stem cells (MaSCs)/progenitor cells, might provide potential solutions to these problems and may improve milk production. In addition, MaSCs/progenitor cells could be used in regenerative therapy against tissue damage caused by mastitis. This review discusses methods of MaSC/progenitor cell manipulation and their mechanisms in bovine and caprine animals. Author believes that intervention of MaSCs/progenitor cells could lessen the huge financial losses to the dairy industry globally.

  1. Gene expression array analyses predict increased proto-oncogene expression in MMTV induced mammary tumors.

    PubMed

    Popken-Harris, Pamela; Kirchhof, Nicole; Harrison, Ben; Harris, Lester F

    2006-08-01

    Exogenous infection by milk-borne mouse mammary tumor viruses (MMTV) typically induce mouse mammary tumors in genetically susceptible mice at a rate of 90-95% by 1 year of age. In contrast to other transforming retroviruses, MMTV acts as an insertional mutagen and under the influence of steroid hormones induces oncogenic transformation after insertion into the host genome. As these events correspond with increases in adjacent proto-oncogene transcription, we used expression array profiling to determine which commonly associated MMTV insertion site proto-oncogenes were transcriptionally active in MMTV induced mouse mammary tumors. To verify our gene expression array results we developed real-time quantitative RT-PCR assays for the common MMTV insertion site genes found in RIII/Sa mice (int-1/wnt-1, int-2/fgf-3, int-3/Notch 4, and fgf8/AIGF) as well as two genes that were consistently up regulated (CCND1, and MAT-8) and two genes that were consistently down regulated (FN1 and MAT-8) in the MMTV induced tumors as compared to normal mammary gland. Finally, each tumor was also examined histopathologically. Our expression array findings support a model whereby just one or a few common MMTV insertions into the host genome sets up a dominant cascade of events that leave a characteristic molecular signature.

  2. Innate and Adaptive Immunity Synergize to Trigger Inflammation in the Mammary Gland.

    PubMed

    Rainard, Pascal; Cunha, Patricia; Gilbert, Florence B

    2016-01-01

    The mammary gland is able to detect and react to bacterial intrusion through innate immunity mechanisms, but mammary inflammation can also result from antigen-specific adaptive immunity. We postulated that innate and adaptive immune responses could synergize to trigger inflammation in the mammary gland. To test this hypothesis, we immunized cows with the model antigen ovalbumin and challenged the sensitized animals with either Escherichia coli lipopolysaccharide (LPS) as innate immunity agonist, ovalbumin as adaptive immunity agonist, or both agonists in three different udder quarters of lactating cows. There was a significant amplification of the initial milk leukocytosis in the quarters challenged with the two agonists compared to leukocytosis in quarters challenged with LPS or ovalbumin alone. This synergistic response occurred only with the cows that developed the ovalbumin-specific inflammatory response, and there were significant correlations between milk leukocytosis and production of IL-17A and IFN-γ in a whole-blood ovalbumin stimulation assay. The antigen-specific response induced substantial concentrations of IL-17A and IFN-γ in milk contrary to the response to LPS. Such a synergy at the onset of the reaction of the mammary gland suggests that induction of antigen-specific immune response with bacterial antigens could improve the initial immune response to infection, hence reducing the bacterial load and contributing to protection. PMID:27100324

  3. Activation of int-1 and int-2 loci in GRf mammary tumors.

    PubMed

    Gray, D A; Jackson, D P; Percy, D H; Morris, V L

    1986-10-30

    The Mtv-2 locus is known to be associated with a high mammary tumor incidence (97%) and early development of mammary tumors (3-13 months) in GR mice. However, it was not previously known whether the provirus which resides at the Mtv-2 locus is tumorigenic in and of itself or whether reintegration of proviruses generated from Mtv-2 is required for tumorigenesis. Foster-nursing GR mice on C57/BL mice eliminates the milk-borne source of GR virus, and allows the study of Mtv-2 derived proviruses alone. Using this approach, we have tested predictions which follow from the "positional" versus "reintegrational" models of tumorigenesis. Specifically, we have examined tumors from primary foster-nursed (GRf) mice to determine if MMTV proviruses derived from Mtv-2 were scattered randomly throughout the genome or were clustered in the vicinity of the int-1 and int-2 loci, which are thought to be associated with mammary tumorigenesis. It was found that the majority of spontaneous GRf mammary tumors that were tested have MMTV proviral integrations in either or both of the int-1 and int-2 loci and have transcription of either or both of the int loci. Tumors induced by Mtv-2, therefore, appear to have arisen via a mechanism similar to the activation of the int loci by exogenous (milk-borne) MMTV proviruses.

  4. The Transcriptional Repressor ZNF503/Zeppo2 Promotes Mammary Epithelial Cell Proliferation and Enhances Cell Invasion.

    PubMed

    Shahi, Payam; Slorach, Euan M; Wang, Chih-Yang; Chou, Jonathan; Lu, Angela; Ruderisch, Aline; Werb, Zena

    2015-02-01

    The NET (nocA, Nlz, elB, TLP-1) subfamily of zinc finger proteins is an important mediator during developmental processes. The evolutionary conserved zinc finger protein ZNF503/Zeppo2 (zinc finger elbow-related proline domain protein 2, Zpo2) plays critical roles during embryogenesis. We found that Zpo2 is expressed in adult tissue and examined its function. We found that ZPO2 is a nuclearly targeted transcriptional repressor that is expressed in mammary epithelial cells. Elevated Zpo2 levels increase mammary epithelial cell proliferation. Zpo2 promotes cellular invasion through down-regulation of E-cadherin and regulates the invasive phenotype in a RAC1-dependent manner. We detect elevated Zpo2 expression during breast cancer progression in a MMTV-PyMT transgenic mouse model. Tumor transplant experiments indicated that overexpression of Zpo2 in MMTV-PyMT mammary tumor cell lines enhances lung metastasis. Our findings suggest that Zpo2 plays a significant role in mammary gland homeostasis and that deregulation of Zpo2 may promote breast cancer development.

  5. Suppression of mammary epithelial cell differentiation by the helix-loop-helix protein Id-1

    SciTech Connect

    Desprez, P.; Hara, E.; Bissell, M.J.

    1995-06-01

    Cell proliferation and differentiation are precisely coordinated during the development and maturation of the mammary gland, and this balance invariably is disrupted during carcinogenesis. Little is known about the cell-specific transcription factors that regulate these processes in the mammary gland. The mouse mammary epithelial cell line SCp2 grows well under standard culture conditions but arrests growth, forms alveolus-like structures, and expresses {beta}-casein, a differentiation marker, 4 to 5 days after exposure to basement membrane and lactogenic hormones (differentiation signals). The authors show that this differentiation entails a marked decline in the expression of Id-1, a helix-loop-helix (HLH) protein that inactivates basic HLH transcription factors in other cell types. SCp2 cells stably transfected with an Id-1 expression vector grew more rapidly than control cells under standard conditions, but in response to differentiation signals, they lost three-dimensional organization, invaded the basement membrane, and then resumed growth. SCp2 cells expressing an Id-1 antisense vector grew more slowly than controls; in response to differentiation signals, they remained stably growth arrested and fully differentiated, as did control cells. The authors suggest that Id-1 renders cells refractory to differentiation signals and receptive to growth signals by inactivating one or more basic HLH proteins that coordinate growth and differentiation in the mammary epithelium. 53 refs., 6 figs.

  6. Innate and Adaptive Immunity Synergize to Trigger Inflammation in the Mammary Gland

    PubMed Central

    Rainard, Pascal; Cunha, Patricia; Gilbert, Florence B.

    2016-01-01

    The mammary gland is able to detect and react to bacterial intrusion through innate immunity mechanisms, but mammary inflammation can also result from antigen-specific adaptive immunity. We postulated that innate and adaptive immune responses could synergize to trigger inflammation in the mammary gland. To test this hypothesis, we immunized cows with the model antigen ovalbumin and challenged the sensitized animals with either Escherichia coli lipopolysaccharide (LPS) as innate immunity agonist, ovalbumin as adaptive immunity agonist, or both agonists in three different udder quarters of lactating cows. There was a significant amplification of the initial milk leukocytosis in the quarters challenged with the two agonists compared to leukocytosis in quarters challenged with LPS or ovalbumin alone. This synergistic response occurred only with the cows that developed the ovalbumin-specific inflammatory response, and there were significant correlations between milk leukocytosis and production of IL-17A and IFN-γ in a whole-blood ovalbumin stimulation assay. The antigen-specific response induced substantial concentrations of IL-17A and IFN-γ in milk contrary to the response to LPS. Such a synergy at the onset of the reaction of the mammary gland suggests that induction of antigen-specific immune response with bacterial antigens could improve the initial immune response to infection, hence reducing the bacterial load and contributing to protection. PMID:27100324

  7. MMTV insertional mutagenesis identifies genes, gene families and pathways involved in mammary cancer.

    PubMed

    Theodorou, Vassiliki; Kimm, Melanie A; Boer, Mandy; Wessels, Lodewyk; Theelen, Wendy; Jonkers, Jos; Hilkens, John

    2007-06-01

    We performed a high-throughput retroviral insertional mutagenesis screen in mouse mammary tumor virus (MMTV)-induced mammary tumors and identified 33 common insertion sites, of which 17 genes were previously not known to be associated with mammary cancer and 13 had not previously been linked to cancer in general. Although members of the Wnt and fibroblast growth factors (Fgf) families were frequently tagged, our exhaustive screening for MMTV insertion sites uncovered a new repertoire of candidate breast cancer oncogenes. We validated one of these genes, Rspo3, as an oncogene by overexpression in a p53-deficient mammary epithelial cell line. The human orthologs of the candidate oncogenes were frequently deregulated in human breast cancers and associated with several tumor parameters. Computational analysis of all MMTV-tagged genes uncovered specific gene families not previously associated with cancer and showed a significant overrepresentation of protein domains and signaling pathways mainly associated with development and growth factor signaling. Comparison of all tagged genes in MMTV and Moloney murine leukemia virus-induced malignancies showed that both viruses target mostly different genes that act predominantly in distinct pathways.

  8. A role for T-lymphocytes in human breast cancer and in canine mammary tumors.

    PubMed

    Carvalho, Maria Isabel; Pires, Isabel; Prada, Justina; Queiroga, Felisbina L

    2014-01-01

    Chronic inflammation in the tumor microenvironment has a prominent role in carcinogenesis and benefits the proliferation and survival of malignant cells, promoting angiogenesis and metastasis. Mammary tumors are frequently infiltrated by a heterogeneous population of immune cells where T-lymphocytes have a great importance. Interestingly, similar inflammatory cell infiltrates, cytokine and chemokine expression in humans and canine mammary tumors were recently described. However, in both species, despite all the scientific evidences that appoint for a significant role of T-lymphocytes, a definitive conclusion concerning the effectiveness of T-cell dependent immune mechanisms has not been achieved yet. In the present review, we describe similarities between human breast cancer and canine mammary tumors regarding tumor T-lymphocyte infiltration, such as relationship of TILs and mammary tumors malignancy, association of ratio CD4+/ CD8+ T-cells with low survival rates, promotion of tumor progression by Th2 cells actions, and association of great amounts of Treg cells with poor prognostic factors. This apparent parallelism together with the fact that dogs develop spontaneous tumors in the context of a natural immune system highlight the dog as a possible useful biological model for studies in human breast cancer immunology. PMID:24672781

  9. Estrogenic Plant Extracts Reverse Weight Gain and Fat Accumulation without Causing Mammary Gland or Uterine Proliferation

    PubMed Central

    Saunier, Elise F.; Vivar, Omar I.; Rubenstein, Andrea; Zhao, Xiaoyue; Olshansky, Moshe; Baggett, Scott; Staub, Richard E.; Tagliaferri, Mary; Cohen, Isaac; Speed, Terence P.; Baxter, John D.; Leitman, Dale C.

    2011-01-01

    Long-term estrogen deficiency increases the risk of obesity, diabetes and metabolic syndrome in postmenopausal women. Menopausal hormone therapy containing estrogens might prevent these conditions, but its prolonged use increases the risk of breast cancer, as wells as endometrial cancer if used without progestins. Animal studies indicate that beneficial effects of estrogens in adipose tissue and adverse effects on mammary gland and uterus are mediated by estrogen receptor alpha (ERα). One strategy to improve the safety of estrogens to prevent/treat obesity, diabetes and metabolic syndrome is to develop estrogens that act as agonists in adipose tissue, but not in mammary gland and uterus. We considered plant extracts, which have been the source of many pharmaceuticals, as a source of tissue selective estrogens. Extracts from two plants, Glycyrrhiza uralensis (RG) and Pueraria montana var. lobata (RP) bound to ERα, activated ERα responsive reporters, and reversed weight gain and fat accumulation comparable to estradiol in ovariectomized obese mice maintained on a high fat diet. Unlike estradiol, RG and RP did not induce proliferative effects on mammary gland and uterus. Gene expression profiling demonstrated that RG and RP induced estradiol-like regulation of genes in abdominal fat, but not in mammary gland and uterus. The compounds in extracts from RG and RP might constitute a new class of tissue selective estrogens to reverse weight gain, fat accumulation and metabolic syndrome in postmenopausal women. PMID:22163294

  10. Radiation induces genomic instability and mammary ductal dysplasia in Atm heterozygous mice

    NASA Technical Reports Server (NTRS)

    Weil, M. M.; Kittrell, F. S.; Yu, Y.; McCarthy, M.; Zabriskie, R. C.; Ullrich, R. L.

    2001-01-01

    Ataxia-telangiectasia (AT) is a genetic syndrome resulting from the inheritance of two defective copies of the ATM gene that includes among its stigmata radiosensitivity and cancer susceptibility. Epidemiological studies have demonstrated that although women with a single defective copy of ATM (AT heterozygotes) appear clinically normal, they may never the less have an increased relative risk of developing breast cancer. Whether they are at increased risk for radiation-induced breast cancer from medical exposures to ionizing radiation is unknown. We have used a murine model of AT to investigate the effect of a single defective Atm allele, the murine homologue of ATM, on the susceptibility of mammary epithelial cells to radiation-induced transformation. Here we report that mammary epithelial cells from irradiated mice with one copy of Atm truncated in the PI-3 kinase domain were susceptible to radiation-induced genomic instability and generated a 10% incidence of dysplastic mammary ducts when transplanted into syngenic recipients, whereas cells from Atm(+/+) mice were stable and formed only normal ducts. Since radiation-induced ductal dysplasia is a precursor to mammary cancer, the results indicate that AT heterozygosity increases susceptibility to radiogenic breast cancer in this murine model system.

  11. Stromal fibroblasts derived from mammary gland of bovine with mastitis display inflammation-specific changes

    PubMed Central

    Chen, Qing; He, Guiliang; Zhang, Wenyao; Xu, Tong; Qi, Hongliang; Li, Jing; Zhang, Yong; Gao, Ming-Qing

    2016-01-01

    Fibroblasts are predominant components of mammary stromal cells and play crucial roles in the development and involution of bovine mammary gland; however, whether these cells contribute to mastitis has not been demonstrated. Thus, we have undertaken biological and molecular characterization of inflammation-associated fibroblasts (INFs) extracted from bovine mammary glands with clinical mastitis and normal fibroblasts (NFs) from slaughtered dairy cows because of fractured legs during lactation. The functional contributions of INFs to normal epithelial cells were also investigated by using an in vitro co-culture model. We present evidence that the INFs were activated fibroblasts and showed inflammation-related features. Moreover, INFs significantly inhibited the proliferation and β-casein secretion of epithelial cells, as well as upregulated the expression of tumor necrosis factor-α and interleukin-8 in epithelial cells. These findings indicate that functional alterations can occur in stromal fibroblasts within the bovine mammary gland during mastitis, demonstrating the importance of stromal fibroblasts in bovine mastitis and its treatment. PMID:27272504

  12. Effects of 900 MHz GSM wireless communication signals on DMBA-induced mammary tumors in rats.

    PubMed

    Yu, Da; Shen, Yonghao; Kuster, Niels; Fu, Yiti; Chiang, Huai

    2006-02-01

    The purpose of the study was to investigate whether exposure to 900 MHz GSM wireless communication signals enhances mammary tumor development and growth induced by low-dose DMBA. Five hundred female Sprague-Dawley rats were treated with a single dose of 35 mg/kg DMBA and then divided into five groups in a blinded fashion: one cage control group and four exposure groups, including three microwave exposure groups and one sham exposure with specific absorption rates (SARs) of 4.0, 1.33, 0.44 and 0 W/kg, respectively. Exposure started on the day after DMBA administration and lasted 4 h/day, 5 days/week for 26 weeks. Rats were weighed and palpated weekly for the presence of tumors and were killed humanely at the end of the 26-week exposure period. All mammary glands were examined histologically. There were no statistically significant differences in body weight between sham- and GSM microwave-exposed groups. No significant differences in overall mammary tumor incidence, latency to tumor onset, tumor multiplicity, or tumor size were observed between microwave- and sham-exposed groups. There was a tendency for reduction of mammary adenocarcinoma incidence in the lowest microwave exposure group (0.44 W/ kg) compared with the sham-exposed group (P = 0.058). Additionally, a higher incidence of adenocarcinoma was noticed in the 4.0 W/kg group from the 15th to 26th weeks, especially in the 19th week (P = 0.358 compared to sham). However, neither tendency was statistically significant; thus this study does not provide evidence that GSM microwave exposure promotes mammary tumor development in rats. In the present study there were significant differences between the cage controls and the experimental groups (sham and exposure). Body weight and mammary tumor (malignant plus benign) incidence in the cage control group were significantly higher than in the sham- and GSM microwave-exposed groups. The latency to the mammary tumor onset was significantly shorter in the cage control

  13. Amplification of mouse mammary tumor virus genomes in non-mammary tumor cells.

    PubMed Central

    Racevskis, J; Beyer, H

    1989-01-01

    Extra proviral copies of mouse mammary tumor virus (MMTV) are known to be present in the genomes of certain T-cell lymphomas of mice. Analysis of additional non-mammary tumor cell types known to express MMTV transcripts and antigens revealed the presence of extra acquired MMTV proviruses in a pituitary tumor cell line, a macrophage line, and Leydig testicular tumor cells. The nature of the amplified MMTV proviruses in these various tumor cell types differed with regard to copy number and presence of alterations in the long terminal repeat region. Images PMID:2535749

  14. Human breast cancer cells are redirected to mammary epithelial cells upon interaction with the regenerating mammary gland microenvironment in-vivo.

    PubMed

    Bussard, Karen M; Smith, Gilbert H

    2012-01-01

    Breast cancer is the second leading cause of cancer deaths in the United States. At present, the etiology of breast cancer is unknown; however the possibility of a distinct cell of origin, i.e. a cancer stem cell, is a heavily investigated area of research. Influencing signals from the tissue niche are known to affect stem cells. Literature has shown that cancer cells lose their tumorigenic potential and display 'normal' behavior when placed into 'normal' ontogenic environments. Therefore, it may be the case that the tissue microenvironment is able to generate signals to redirect cancer cell fate. Previously, we showed that pluripotent human embryonal carcinoma cells could be redirected by the regenerating mammary gland microenvironment to contribute epithelial progeny for 'normal' gland development in-vivo. Here, we show that that human metastatic, non-metastatic, and metastasis-suppressed breast cancer cells proliferate and contribute to normal mammary gland development in-vivo without tumor formation. Immunochemistry for human-specific mitochondria, keratin 8 and 14, as well as human-specific milk proteins (alpha-lactalbumin, impregnated transplant hosts) confirmed the presence of human cell progeny. Features consistent with normal mammary gland development as seen in intact hosts (duct, lumen formation, development of secretory acini) were recapitulated in both primary and secondary outgrowths from chimeric implants. These results suggest the dominance of the tissue microenvironment over cancer cell fate. This work demonstrates that cultured human breast cancer cells (metastatic and non-metastatic) respond developmentally to signals generated by the mouse mammary gland microenvironment during gland regeneration in-vivo.

  15. Scribble Modulates the MAPK/Fra1 Pathway to Disrupt Luminal and Ductal Integrity and Suppress Tumour Formation in the Mammary Gland

    PubMed Central

    Godde, Nathan J.; Sheridan, Julie M.; Smith, Lorey K.; Pearson, Helen B.; Britt, Kara L.; Galea, Ryan C.; Yates, Laura L.; Visvader, Jane E.; Humbert, Patrick O.

    2014-01-01

    Polarity coordinates cell movement, differentiation, proliferation and apoptosis to build and maintain complex epithelial tissues such as the mammary gland. Loss of polarity and the deregulation of these processes are critical events in malignant progression but precisely how and at which stage polarity loss impacts on mammary development and tumourigenesis is unclear. Scrib is a core polarity regulator and tumour suppressor gene however to date our understanding of Scrib function in the mammary gland has been limited to cell culture and transplantation studies of cell lines. Utilizing a conditional mouse model of Scrib loss we report for the first time that Scrib is essential for mammary duct morphogenesis, mammary progenitor cell fate and maintenance, and we demonstrate a critical and specific role for Scribble in the control of the early steps of breast cancer progression. In particular, Scrib-deficiency significantly induced Fra1 expression and basal progenitor clonogenicity, which resulted in fully penetrant ductal hyperplasia characterized by high cell turnover, MAPK hyperactivity, frank polarity loss with mixing of apical and basolateral membrane constituents and expansion of atypical luminal cells. We also show for the first time a role for Scribble in mammalian spindle orientation with the onset of mammary hyperplasia being associated with aberrant luminal cell spindle orientation and a failure to apoptose during the final stage of duct tubulogenesis. Restoring MAPK/Fra1 to baseline levels prevented Scrib-hyperplasia, whereas persistent Scrib deficiency induced alveolar hyperplasia and increased the incidence, onset and grade of mammary tumours. These findings, based on a definitive genetic mouse model provide fundamental insights into mammary duct maturation and homeostasis and reveal that Scrib loss activates a MAPK/Fra1 pathway that alters mammary progenitor activity to drive premalignancy and accelerate tumour progression. PMID:24852022

  16. Pomegranate exerts chemoprevention of experimentally induced mammary tumorigenesis by suppression of cell proliferation and induction of apoptosis

    PubMed Central

    Bishayee, Anupam; Mandal, Animesh; Bhattacharyya, Piyali; Bhatia, Deepak

    2016-01-01

    abstract Breast cancer is the second leading cause of cancer-related death in women in the United States and discovery and development of safe chemopreventive drugs is urgently needed. The fruit pomegranate (Punica granatum) is gaining importance because of its various health benefits. This study was initiated to investigate chemopreventive potential of a pomegranate emulsion (PE) against 7,12-dimethylbenz(a)anthracene (DMBA) rat mammary carcinogenesis. The animals were orally administered with PE (0.2–5.0 g/kg), starting 2 wk before and 16 wk following DMBA treatment. PE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden, and reversed histopathological changes. PE dose-dependently suppressed cell proliferation and induced apoptosis in mammary tumors. Immunohistochemical studies showed that PE increased intratumor Bax, decreased Bcl2 and manifested a proapoptotic shift in Bax/Bcl2 ratio. In addition, our gene expression study showed PE-mediated upregulation of Bad, caspase-3, caspase-7, caspase-9, poly (ADP ribose) polymerase and cytochrome c in mammary tumors. Thus, PE exerts chemoprevention of mammary carcinogenesis by suppressing cell proliferation and inducing apoptosis mediated through upregulation of Bax and downregulation of Bcl2 in concert with caspase cascades. Pomegranate bioactive phytoconstituents could be developed as a chemopreventive drug to reduce the risk of breast cancer. PMID:26699876

  17. Pomegranate exerts chemoprevention of experimentally induced mammary tumorigenesis by suppression of cell proliferation and induction of apoptosis.

    PubMed

    Bishayee, Anupam; Mandal, Animesh; Bhattacharyya, Piyali; Bhatia, Deepak

    2016-01-01

    Breast cancer is the second leading cause of cancer-related death in women in the United States and discovery and development of safe chemopreventive drugs is urgently needed. The fruit pomegranate (Punica granatum) is gaining importance because of its various health benefits. This study was initiated to investigate chemopreventive potential of a pomegranate emulsion (PE) against 7,12-dimethylbenz(a)anthracene (DMBA) rat mammary carcinogenesis. The animals were orally administered with PE (0.2-5.0 g/kg), starting 2 wk before and 16 wk following DMBA treatment. PE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden, and reversed histopathological changes. PE dose-dependently suppressed cell proliferation and induced apoptosis in mammary tumors. Immunohistochemical studies showed that PE increased intratumor Bax, decreased Bcl2 and manifested a proapoptotic shift in Bax/Bcl2 ratio. In addition, our gene expression study showed PE-mediated upregulation of Bad, caspase-3, caspase-7, caspase-9, poly (ADP ribose) polymerase and cytochrome c in mammary tumors. Thus, PE exerts chemoprevention of mammary carcinogenesis by suppressing cell proliferation and inducing apoptosis mediated through upregulation of Bax and downregulation of Bcl2 in concert with caspase cascades. Pomegranate bioactive phytoconstituents could be developed as a chemopreventive drug to reduce the risk of breast cancer. PMID:26699876

  18. Multiphoton intravital microscopy setup to visualize the mouse mammary gland

    NASA Astrophysics Data System (ADS)

    Adur, Javier; Herrera Torres, Ana M.; Masedunskas, Andrius; Baratti, Mariana O.; de Thomaz, Andre A.; Pelegati, Vitor B.; Carvalho, Hernandes F.; Cesar, Carlos L.

    2013-06-01

    Recently, light microscopy-based techniques have been extended to live mammalian models leading to the development of a new imaging approach called intravital microscopy (IVM). Although IVM has been introduced at the beginning of the last century, its major advancements have occurred in the last twenty years with the development of non-linear microscopy that has enabled performing deep tissue imaging. IVM has been utilized to address many biological questions in basic research and is now a fundamental tool that provide information on tissues such as morphology, cellular architecture, and metabolic status. IVM has become an indispensable tool in numerous areas. This study presents and describes the practical aspects of IVM necessary to visualize epithelial cells of live mouse mammary gland with multiphoton techniques.

  19. Induction of mammary tumors in aging rats by 7,12-dimethylbenz(a)anthracene: role of DNA synthesis during carcinogenesis

    SciTech Connect

    Sinha, D.K.; Dao, T.L.

    1980-03-01

    Two routes of administration were used to test the susceptibility of the mammary gland of the rat to 7,12-dimethylbenz(a)anthracene (DMBA) carcinogenesis in relation to age of the tissue. In one series of experiments, 60-, 70-, 90-, 120-, 150-, and 200-day-old female nonbred Sprague-Dawley rats were given DMBA iv. In parallel experiments, rats of the same ages as those above were given DMBA by local application. Mammary tumors developed in 89 to 90% of the 60- and 70-day-old rats and in 40% of the 90-day-old rats. Rats 120 days old and older were completely refractory to DMBA. In contrast, all rats, irrespective of their ages, developed tumors when DMBA was applied locally. DMBA given iv significantly inhibited DNA synthesis in mammary glands, but DMBA applied locally significantly increased the Li of the mammary glands.

  20. Transcriptome analysis of the mammary gland from GH transgenic goats during involution.

    PubMed

    Lin, Jian; Bao, Ze Kun; Zhang, Qiang; Hu, Wei Wei; Yu, Qing Hua; Yang, Qian

    2015-07-10

    Mammary glands are organs for milk production in female mammals. Growth hormone (GH) is known to affect the growth and development of the mammary gland, as well as to increase milk production in dairy goats. This study performed a comprehensive expression profiling of genes expressed in the mammary gland of early involution GH transgenic (n=4) and non-transgenic goats (n=4) by RNA sequencing. RNA was extracted from mammary gland tissues collected at day 3 of involution. Gene expression analysis was conducted by Illumina RNA sequencing and sequence reads were assembled and analyzed using TopHat. FPKM (fragments per kilobase of exon per million) values were analyzed for differentially expressed genes using the Cufflinks package. Gene ontology analysis of differentially expressed genes was categorized using agriGO, while KEGG pathway analysis was performed with the online KEGG automatic annotation server. Our results revealed that 75% of NCBI goat annotated genes were expressed during early involution. A total of 18,323 genes were expressed during early involution in GH transgenic goats, compared with 18,196 expressed genes during early involution of non-transgenic goats. In these expressed genes, the majority (17,589) were ubiquitously expressed in GH transgenic and non-transgenic goats. However, there were 745 differentially expressed genes, 421 of which were upregulated and 324 were downregulated in GH transgenic goats. GO and KEGG pathway analysis showed that these genes were involved in mammary gland physiology, including cell adhesion molecules, ECM-receptor interaction, Jak-STAT signaling pathway, and fat metabolism. Our results demonstrated that the GH receptor was strongly affected in GH transgenic goats, which may activate the IGF-1/Stat3 signaling pathway. Overall, our study provided a global view of the transcriptome during involution of GH transgenic and non-transgenic goats, which increases our understanding of the biology of involution in the goat.

  1. Combination of intermittent calorie restriction and eicosapentaenoic acid for inhibition of mammary tumors

    PubMed Central

    Mizuno, Nancy K.; Rogozina, Olga P.; Seppanen, Christine M.; Liao, D. Joshua; Cleary, Margot P.; Grossmann, Michael E.

    2013-01-01

    There are a number of dietary interventions capable of inhibiting mammary tumorigenesis however the effectiveness of dietary combinations is largely unexplored. Here we combined two interventions previously shown individually to inhibit mammary tumor development. The first was the use of the omega-3 fatty acid, eicosapentaenoic acid (EPA), and the second was the implementation of calorie restriction. MMTV-Her2/neu mice were used as a model for human breast cancers which over express Her2/neu. Six groups of mice were enrolled. Half were fed a control (Con) diet with 10.1% fat calories from soy oil, while the other half consumed a diet with 72% fat calories from EPA. Within each diet mice were further divided into ad libitum (AL), chronic calorie restricted (CCR) or intermittent calorie restricted (ICR) groups. Mammary tumor incidence was lowest in ICR-EPA (15%) and highest in AL-Con mice (87%) while AL-EPA, CCR-Con, CCR-EPA and ICR-Con groups had mammary tumor incidence rates of 63%, 47%, 40% and 59% respectively. Survival was effected similarly by the interventions. Consumption of EPA dramatically reduced serum leptin (P<0.02) and increased serum adiponectin in the AL-EPA mice compared to AL-Con mice (P<0.001). Both CCR and ICR decreased serum leptin and IGF-I compared to AL mice but not compared to each other. These results illustrate that mammary tumor inhibition is significantly increased when ICR and EPA are combined as compared to either intervention alone. This response may be related to alterations in the balance of serum growth factors and adipokines. PMID:23550153

  2. Inhibition of radiogenic mammary carcinoma in rats by estriol or tamoxifen

    SciTech Connect

    Lemon, H.M.; Kumar, P.F.; Peterson, C.; Rodriguez-Sierra, J.F.; Abbo, K.M.

    1989-05-01

    Mammary carcinomas have been induced by 3.5 Gy whole-body gamma radiation administered at age 40 to 50 days to virgin female Sprague-Dawley rats. In 142 irradiated controls carcinoma incidence averaged 7.8% in survivors observed less than 300 days and 38.3% of those surviving longer (P less than 0.001 by t test). Mammary cancer promotion was inhibited by two methods: estriol (E3) 638 micrograms/month (2.2 microns/mo) subcutaneously for natural life span begun 2 weeks after exposure reduced cancer incidence from 76% in controls to 48% after 331 to 449 mean days observation until neoplasia was palpable (P less than 0.02 by chi-square analysis). Uterine weights were similar in control and treated groups, and were 15% to 18% greater than uteri of nonirradiated controls from other simultaneous experiments. Six monthly 638-micrograms doses of 17 alpha ethinyl estriol (EE3) reduced tumors from 88% in controls to 64% (P less than 0.05 by chi-square analysis) and delayed cancer onset (P less than 0.01-0.04 by life table analysis). Ethinyl estradiol (EE2) after 6 months' treatment similarly delayed mammary tumor development reducing incidence to 75% (NS), with a six-fold increase in nonmammary epithelial malignant tumors. Estriol administration begun between 3 days before to 5 days after radiation did not alter mammary cancer incidence in six experiments. Monthly implantation of 2.5 mg tamoxifen (4.44 microns/mo) started 2 weeks after radiation reduced mammary cancer incidence from 83% to 14% after 307 to 314 days' observation (P less than 0.001 by chi-square analysis). Treated rats had atrophic ovaries and uteri consistent with blockade of endogenous estradiol activity.

  3. Differential expression of living mammary epithelial cell subpopulations in milk during lactation in dairy cows.

    PubMed

    Baratta, M; Volpe, M G; Nucera, D; Gabai, G; Guzzo, N; Fustini, M; Faustini, M; Martignani, E

    2015-10-01

    Epithelial cells are shed into milk during lactation, and although they generally reflect the cellular characteristics of terminally differentiated luminal cells, previously the detection of more primitive cells was described in human milk where a cell population of epithelial lineage was detected expressing markers typical of progenitor cells. In this investigation, we report the development of flow cytometry analysis to allow multiparametric assessment of mammary epithelial cells observed in milk. Cells collected from milk samples of 10 healthy dairy cows were directly analyzed for 6 different markers: CD45, CD49f, cytokeratin 14, cytokeratin 18, presence of nucleus, and cell viability. Milk samples were collected in 3 different periods of lactation: early lactation (EL=d 0-30), mid-lactation (ML=d 90-120), and late lactation (LL=210-250). Here we identify the differential expression of precursor or differentiated cell markers (or both) in mammary epithelial cells present in bovine milk. Myoepithelial cells, as indicated by cells staining positively for cytokeratin 14(+)/cytokeratin 18(-), were observed to increase from EL to LL with a high correlation with nuclear staining inferring potential proliferative activity. Furthermore, a significant increase in CD49f(+) and cytokeratin 14(+)/cytokeratin 18(+) positive cells was observed in LL. This assay is a sensitive approach for evaluating the variations in the frequency and features of living epithelial cells, whose reciprocal balance may be significant in understanding mammary gland cellular function throughout lactation. These observations suggest that mammary epithelial cell immunophenotypes could be investigated as biomarkers for mammary gland function in dairy cows.

  4. SPRY1 regulates mammary epithelial morphogenesis by modulating EGFR-dependent stromal paracrine signaling and ECM remodeling.

    PubMed

    Koledova, Zuzana; Zhang, Xiaohong; Streuli, Charles; Clarke, Robert B; Klein, Ophir D; Werb, Zena; Lu, Pengfei

    2016-09-27

    The role of the local microenvironment in influencing cell behavior is central to both normal development and cancer formation. Here, we show that sprouty 1 (SPRY1) modulates the microenvironment to enable proper mammary branching morphogenesis. This process occurs through negative regulation of epidermal growth factor receptor (EGFR) signaling in mammary stroma. Loss of SPRY1 resulted in up-regulation of EGFR-extracellular signal-regulated kinase (ERK) signaling in response to amphiregulin and transforming growth factor alpha stimulation. Consequently, stromal paracrine signaling and ECM remodeling is augmented, leading to increased epithelial branching in the mutant gland. By contrast, down-regulation of EGFR-ERK signaling due to gain of Sprouty function in the stroma led to stunted epithelial branching. Taken together, our results show that modulation of stromal paracrine signaling and ECM remodeling by SPRY1 regulates mammary epithelial morphogenesis during postnatal development. PMID:27621461

  5. Retinoids induce lumen morphogenesis in mammary epithelial cells.

    PubMed

    Montesano, Roberto; Soulié, Priscilla

    2002-12-01

    Lumen formation is a fundamental step in the development of the structural and functional units of glandular organs, such as alveoli and ducts. In an attempt to elucidate the molecular signals that govern this morphogenetic event, we set up an in vitro system in which cloned mammary epithelial cells grown in collagen gels under serum-free conditions form solid, lumen-less colonies. Addition of as little as 0.1% donor calf serum (DCS) was sufficient to induce the formation of a central cavity. Among a number of serum constituents analyzed, retinol was found to mimic the effect of DCS in inducing lumen morphogenesis. Since the biological activities of retinol are largely dependent on its conversion to all-trans-retinoic acid (RA), we examined in more detail the effect of RA on lumen formation. RA induced the formation of lumen-containing colonies (cysts) in a concentration- and time-dependent manner, a half-maximal effect after 9 days of culture being observed with 100 pM RA. The pleiotropic effects of retinoids are mediated by nuclear retinoic acid receptors (RARs; alpha, beta and gamma) and retinoid X receptors (RXRs; alpha, beta and gamma). To identify the signaling pathway involved in RA-induced lumen formation, we used receptor-specific synthetic retinoids. TTNPB, a selective RAR agonist, promoted lumen morphogenesis, whereas RXR-selective ligands lacked this activity. Lumen formation was also induced at picomolar concentrations by Am-580, a synthetic retinoid that selectively binds the RARalpha receptor subtype. Moreover, co-addition of Ro 41-5253, an antagonist of RARalpha, abrogated the lumen-inducing activity of both RA and DCS, indicating that this biological response is mediated through an RARalpha-dependent signaling pathway. To gain insight into the mechanisms underlying RA-induced lumen formation, we assessed the potential role of matrix metalloproteinases (MMP). Using gelatin zymography, we observed a dose-dependent increase in latent and active forms

  6. 9 CFR 310.17 - Inspection of mammary glands.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... mammary glands and diseased mammary glands of cattle, sheep, swine, and goats shall be removed without opening the milk ducts or sinuses. If pus or other objectionable material is permitted to come in contact..., swine, and goats shall not be saved for edible purposes. (d) The udders from cows officially...

  7. 9 CFR 310.17 - Inspection of mammary glands.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... mammary glands and diseased mammary glands of cattle, sheep, swine, and goats shall be removed without opening the milk ducts or sinuses. If pus or other objectionable material is permitted to come in contact..., swine, and goats shall not be saved for edible purposes. (d) The udders from cows officially...

  8. Bovine mammary stem cells: Cell biology meets production agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mammary stem cells (MaSC) provide for net growth, renewal and turnover of mammary epithelial cells, and are therefore potential targets for strategies to increase production efficiency. Appropriate regulation of MaSC can potentially benefit milk yield, persistency, dry period management and tissue ...

  9. Type 1 receptor tyrosine kinases are differentially phosphorylated in mammary carcinoma and differentially associated with steroid receptors.

    PubMed Central

    Bacus, S. S.; Chin, D.; Yarden, Y.; Zelnick, C. R.; Stern, D. F.

    1996-01-01

    The neu/erbB-2/HER-2 proto-oncogene is amplified and/or overexpressed in up to 30% of mammary carcinomas and has been variably correlated with poor prognosis. The signaling activity of the encoded receptor tyrosine kinase is regulated by interactions with other type 1 receptors and their ligands. We have used a novel approach, phosphorylation-sensitive anti-Neu antibodies, to quantify signaling by Neu and epidermal growth factor receptor in a panel of frozen sections of mammary carcinoma specimens. We also determined the relationship of Neu, phosphorylated Neu (and epidermal growth factor receptor), and phosphotyrosine to the expression of Neu-related receptors (epidermal growth factor receptor, HER-3, and HER-4) and to prognostic factors (estrogen and progesterone receptor). We found that tyrosine phosphorylation of Neu (and hence signaling activity) is highly variable among mammary carcinomas. Neu and HER-4 were associated with divergent correlates, suggesting that they have profoundly different biological activities. These results have implications for etiology of mammary carcinoma for clinical evaluation of mammary carcinoma patients, and for development of Neu-targeted therapeutic strategies. Images Figure 1 Figure 2 PMID:8579117

  10. Expression and function of the protein tyrosine phosphatase receptor J (PTPRJ) in normal mammary epithelial cells and breast tumors.

    PubMed

    Smart, Chanel E; Askarian Amiri, Marjan E; Wronski, Ania; Dinger, Marcel E; Crawford, Joanna; Ovchinnikov, Dmitry A; Vargas, Ana Cristina; Reid, Lynne; Simpson, Peter T; Song, Sarah; Wiesner, Christiane; French, Juliet D; Dave, Richa K; da Silva, Leonard; Purdon, Amy; Andrew, Megan; Mattick, John S; Lakhani, Sunil R; Brown, Melissa A; Kellie, Stuart

    2012-01-01

    The protein tyrosine phosphatase receptor J, PTPRJ, is a tumor suppressor gene that has been implicated in a range of cancers, including breast cancer, yet little is known about its role in normal breast physiology or in mammary gland tumorigenesis. In this paper we show that PTPRJ mRNA is expressed in normal breast tissue and reduced in corresponding tumors. Meta-analysis revealed that the gene encoding PTPRJ is frequently lost in breast tumors and that low expression of the transcript associated with poorer overall survival at 20 years. Immunohistochemistry of PTPRJ protein in normal human breast tissue revealed a distinctive apical localisation in the luminal cells of alveoli and ducts. Qualitative analysis of a cohort of invasive ductal carcinomas revealed retention of normal apical PTPRJ localization where tubule formation was maintained but that tumors mostly exhibited diffuse cytoplasmic staining, indicating that dysregulation of localisation associated with loss of tissue architecture in tumorigenesis. The murine ortholog, Ptprj, exhibited a similar localisation in normal mammary gland, and was differentially regulated throughout lactational development, and in an in vitro model of mammary epithelial differentiation. Furthermore, ectopic expression of human PTPRJ in HC11 murine mammary epithelial cells inhibited dome formation. These data indicate that PTPRJ may regulate differentiation of normal mammary epithelia and that dysregulation of protein localisation may be associated with tumorigenesis.

  11. The WNT-controlled transcriptional regulator LBH is required for mammary stem cell expansion and maintenance of the basal lineage

    PubMed Central

    Lindley, Linsey E.; Curtis, Kevin M.; Sanchez-Mejias, Avencia; Rieger, Megan E.; Robbins, David J.; Briegel, Karoline J.

    2015-01-01

    The identification of multipotent mammary stem cells (MaSCs) has provided an explanation for the unique regenerative capacity of the mammary gland throughout adult life. However, it remains unclear what genes maintain MaSCs and control their specification into the two epithelial lineages: luminal and basal. LBH is a novel transcription co-factor in the WNT pathway with hitherto unknown physiological function. LBH is expressed during mammary gland development and aberrantly overexpressed in aggressive ‘basal’ subtype breast cancers. Here, we have explored the in vivo role of LBH in mammopoiesis. We show that in postnatal mammary epithelia, LBH is predominantly expressed in the Lin−CD29highCD24+ basal MaSC population. Upon conditional inactivation of LBH, mice exhibit pronounced delays in mammary tissue expansion during puberty and pregnancy, accompanied by increased luminal differentiation at the expense of basal lineage specification. These defects could be traced to a severe reduction in the frequency and self-renewal/differentiation potential of basal MaSCs. Mechanistically, LBH induces expression of key epithelial stem cell transcription factor ΔNp63 to promote a basal MaSC state and repress luminal differentiation genes, mainly that encoding estrogen receptor α (Esr1/ERα). Collectively, these studies identify LBH as an essential regulator of basal MaSC expansion/maintenance, raising important implications for its potential role in breast cancer pathogenesis. PMID:25655704

  12. Autophagy mitigates metabolic stress and genome damage in mammary tumorigenesis

    PubMed Central

    Karantza-Wadsworth, Vassiliki; Patel, Shyam; Kravchuk, Olga; Chen, Guanghua; Mathew, Robin; Jin, Shengkan; White, Eileen

    2007-01-01

    Autophagy is a catabolic process involving self-digestion of cellular organelles during starvation as a means of cell survival; however, if it proceeds to completion, autophagy can lead to cell death. Autophagy is also a haploinsufficient tumor suppressor mechanism for mammary tumorigenesis, as the essential autophagy regulator beclin1 is monoallelically deleted in breast carcinomas. However, the mechanism by which autophagy suppresses breast cancer remains elusive. Here we show that allelic loss of beclin1 and defective autophagy sensitized mammary epithelial cells to metabolic stress and accelerated lumen formation in mammary acini. Autophagy defects also activated the DNA damage response in vitro and in mammary tumors in vivo, promoted gene amplification, and synergized with defective apoptosis to promote mammary tumorigenesis. Therefore, we propose that autophagy limits metabolic stress to protect the genome, and that defective autophagy increases DNA damage and genomic instability that ultimately facilitate breast cancer progression. PMID:17606641

  13. Prenatal TCDD Exposure Predisposes for Mammary Cancer in Rats

    PubMed Central

    Jenkins, Sarah; Rowell, Craig; Wang, Jun; Lamartiniere, Coral A.

    2007-01-01

    Epidemiological data are conflicting in the link between 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure and breast cancer causation. We have hypothesized that timing of exposure to endocrine disruptors, such as TCDD, will alter breast cancer susceptibility. Using a carcinogen induced rat mammary cancer model, we have shown that prenatal exposure to TCDD alters mammary gland differentiation and increases susceptibility for mammary cancer. Investigations into imprinting via DNA methylation mechanisms showed that there were no changes in protein expression in DNA methyltransferases, ER-alpha, ER-beta, GST-pi, or MDGI. Using 2-D gels and mass spectrometry, we have found seven proteins to be differentially regulated, including a decrease in superoxide dismutase 1 (SOD1). Down-regulation of SOD1 could provide an environment ill equipped to deal with subsequent free radical exposure. We conclude that prenatal TCDD can predispose for mammary cancer susceptibility in the adult offspring by altering the mammary proteome. PMID:17157473

  14. Mammary epithelial cells isolated from milk are a valuable, non-invasive source of mammary transcripts

    PubMed Central

    Boutinaud, Marion; Herve, Lucile; Lollivier, Vanessa

    2015-01-01

    Milk is produced in the udder by mammary epithelial cells (MEC). Milk contains MEC, which are gradually exfoliated from the epithelium during lactation. Isolation of MEC from milk using immunomagnetic separation may be a useful non-invasive method to investigate transcriptional regulations in ruminants’ udder. This review aims to describe the process of isolating MEC from milk, to provide an overview on the studies that use this method to analyze gene expression by qRT PCR and to evaluate the validity of this method by analyzing and comparing the results between studies. In several goat and cow studies, consistent reductions in alpha-lactalbumin mRNA levels during once-daily milking (ODM) and in SLC2A1 mRNA level during feed restriction are observed. The effect of ODM on alpha-lactalbumin mRNA level was similarly observed in milk isolated MEC and mammary biopsy. Moreover, we and others showed decreasing alpha-lactalbumin and increasing BAX mRNA levels with advanced stages of lactation in dairy cows and buffalo. The relevance of using the milk-isolated MEC method to analyze mammary gene expression is proven, as the transcript variations were also consistent with milk yield and composition variations under the effect of different factors such as prolactin inhibition or photoperiod. However, the RNA from milk-isolated MEC is particularly sensitive to degradation. This could explain the differences obtained between milk-isolated MEC and mammary biopsy in two studies where gene expression was compared using qRT-PCR or RNA Sequencing analyses. As a conclusion, when the RNA quality is conserved, MEC isolated from milk are a valuable, non-invasive source of mammary mRNA to study various factors that impact milk yield and composition (ODM, feeding level, endocrine status, photoperiod modulation, and stage of lactation). PMID:26579195

  15. The nipple: a simple intersection of mammary gland and integument, but focal point of organ function.

    PubMed

    Koyama, Sachiko; Wu, Hsin-Jung; Easwaran, Teresa; Thopady, Sunil; Foley, John

    2013-06-01

    Having glands that secrete milk to nourish neonatal offspring characterizes all mammals. We provide a brief overview of the development and anatomy of nipples and mammary glands in monotremes, marsupials, and marine mammals, and focus on the nipples and mammary glands in terrestrial eutherian species. We first classify eutherians into three groups: the altricial, precocial, and arboreal types based on their rearing system. We then summarize the physiology of lactation and the cell biology of nipples with specific focus on comparing these in the mouse, cow, and human, which represent the three different groups. Finally we propose that the nipple is an example of specialized epidermis. As specialized epidermis, it is dependent the underlying stroma for development and maintenance in adult life. The development of the nipple and signaling pathways that regulate its formation are described. PMID:23674217

  16. The nipple: a simple intersection of mammary gland and integument, but focal point of organ function.

    PubMed

    Koyama, Sachiko; Wu, Hsin-Jung; Easwaran, Teresa; Thopady, Sunil; Foley, John

    2013-06-01

    Having glands that secrete milk to nourish neonatal offspring characterizes all mammals. We provide a brief overview of the development and anatomy of nipples and mammary glands in monotremes, marsupials, and marine mammals, and focus on the nipples and mammary glands in terrestrial eutherian species. We first classify eutherians into three groups: the altricial, precocial, and arboreal types based on their rearing system. We then summarize the physiology of lactation and the cell biology of nipples with specific focus on comparing these in the mouse, cow, and human, which represent the three different groups. Finally we propose that the nipple is an example of specialized epidermis. As specialized epidermis, it is dependent the underlying stroma for development and maintenance in adult life. The development of the nipple and signaling pathways that regulate its formation are described.

  17. Anatomy of the human mammary gland: Current status of knowledge.

    PubMed

    Hassiotou, Foteini; Geddes, Donna

    2013-01-01

    Mammary glands are unique to mammals, with the specific function of synthesizing, secreting, and delivering milk to the newborn. Given this function, it is only during a pregnancy/lactation cycle that the gland reaches a mature developmental state via hormonal influences at the cellular level that effect drastic modifications in the micro- and macro-anatomy of the gland, resulting in remodeling of the gland into a milk-secretory organ. Pubertal and post-pubertal development of the breast in females aids in preparing it to assume a functional state during pregnancy and lactation. Remarkably, this organ has the capacity to regress to a resting state upon cessation of lactation, and then undergo the same cycle of expansion and regression again in subsequent pregnancies during reproductive life. This plasticity suggests tight hormonal regulation, which is paramount for the normal function of the gland. This review presents the current status of knowledge of the normal macro- and micro-anatomy of the human mammary gland and the distinct changes it undergoes during the key developmental stages that characterize it, from embryonic life through to post-menopausal age. In addition, it discusses recent advances in our understanding of the normal function of the breast during lactation, with special reference to breastmilk, its composition, and how it can be utilized as a tool to advance knowledge on normal and aberrant breast development and function. Finally, anatomical and molecular traits associated with aberrant expansion of the breast are discussed to set the basis for future comparisons that may illuminate the origin of breast cancer.

  18. Effects of hydroxyapatite in combination with far-infrared rays on spontaneous mammary tumorigenesis in SHN mice.

    PubMed

    Udagawa, Yoko; Ishigame, Harumichi; Nagasawa, Hiroshi

    2002-01-01

    We have found that the administration of a diet containing 5% hydroxyapatite (HAP) derived from pig and cattle bones, and exposure to far-infrared rays (FIR) markedly inhibited spontaneous mammary tumorigenesis in SHN mice. Thus, the effect of combined treatment with HAP and FIR on mammary tumorigenesis was examined. The significant inhibition of tumor development by individual treatment with HAP or FIR was not enhanced by combined treatment; instead, the decrease in the inhibitory effect of HAP with age was ameliorated. Associated with this, life span was elongated and a decline in ovarian function was prevented by HAP plus FIR. Normal and preneoplastic growth of mammary glands and plasma component levels were not significantly affected by any treatment. The findings indicate that HAP and FIR have characteristics common to most natural products; in combination with other agents, they have little additive effect, when each is highly active.

  19. Effectiveness of photodynamic therapy for mammary and extra-mammary Paget's disease: a state of the science review

    PubMed Central

    2011-01-01

    Background Paget's disease is a rare skin disorder occurring in the breast (mammary) or in the groin, genital, peri-anal and axillary regions (extra-mammary). Typical treatment involves surgical excision, which in the case of extra-mammary Paget's disease, can lead to significant morbidity. Photodynamic therapy (PDT) which uses a topical or intravenous photosensitizing agent that is activated by a light source to ablate abnormal tissue, offers a minimally invasive alternative. The purpose of this study was to assess the effectiveness of photodynamic therapy in the treatment of Paget's disease. Methods Following Cochrane guidelines, a comprehensive systematic review of all clinical studies and reports examining the use of PDT for mammary and extra-mammary Paget's disease was conducted. Study quality was assessed using the Oxford Levels of Evidence Scale. Results 21 retrospective and 2 prospective non-comparative studies were identified and included in the review: 9 case reports with 1-2 patients and 14 case series with 1-16 patients. These reports totalled 99 patients with 133 extra-mammary Paget's lesions and 3 patients (with 3 lesions) with mammary Paget's disease. Follow-up periods were typically one year or less, with 77/133 extra-mammary lesions exhibiting complete response to PDT. One recurrent mammary skin lesion and two mammary lesions treated concomitantly with surgery also exhibited complete responses. Conclusions Evidence of the effectiveness of PDT for Paget's disease is promising, but limited. This may, in part, be explained by the rarity of the condition, making controlled comparative clinical trials challenging. PMID:21676258

  20. Beneficial bacteria stimulate host immune cells to counteract dietary and genetic predisposition to mammary cancer in mice.

    PubMed

    Lakritz, Jessica R; Poutahidis, Theofilos; Levkovich, Tatiana; Varian, Bernard J; Ibrahim, Yassin M; Chatzigiagkos, Antonis; Mirabal, Sheyla; Alm, Eric J; Erdman, Susan E

    2014-08-01

    Recent studies suggest health benefits including protection from cancer after eating fermented foods such as probiotic yogurt, though the mechanisms are not well understood. Here we tested mechanistic hypotheses using two different animal models: the first model studied development of mammary cancer when eating a Westernized diet, and the second studied animals with a genetic predilection to breast cancer. For the first model, outbred Swiss mice were fed a Westernized chow putting them at increased risk for development of mammary tumors. In this Westernized diet model, mammary carcinogenesis was inhibited by routine exposure to Lactobacillus reuteri ATCC-PTA-6475 in drinking water. The second model was FVB strain erbB2 (HER2) mutant mice, genetically susceptible to mammary tumors mimicking breast cancers in humans, being fed a regular (non-Westernized) chow diet. We found that oral supplement with these purified lactic acid bacteria alone was sufficient to inhibit features of mammary neoplasia in both models. The protective mechanism was determined to be microbially-triggered CD4+CD25+ lymphocytes. When isolated and transplanted into other subjects, these L. reuteri-stimulated lymphocytes were sufficient to convey transplantable anti-cancer protection in the cell recipient animals. These data demonstrate that host immune responses to environmental microbes significantly impact and inhibit cancer progression in distal tissues such as mammary glands, even in genetically susceptible mice. This leads us to conclude that consuming fermentative microbes such as L. reuteri may offer a tractable public health approach to help counteract the accumulated dietary and genetic carcinogenic events integral in the Westernized diet and lifestyle. PMID:24382758

  1. Establishment of a Mammary Carcinoma Cell Line from Syrian Hamsters Treated with N-Methyl-N-Nitrosourea

    PubMed Central

    Coburn, Malari A.; Brueggemann, Sabrina; Bhatia, Shilpa; Cheng, Bing; Li, Benjamin D. L.; Li, Xiao-Lin; Luraguiz, Natalia; Maxuitenko, Yulia Y.; Orchard, Elysse A.; Zhang, Songlin; Stoff-Khalili, Mariam A.; Mathis, J. Michael; Kleiner-Hancock, Heather E.

    2011-01-01

    Clearly new breast cancer models are necessary in developing novel therapies. To address this challenge, we examined mammary tumor formation in the Syrian hamster using the chemical carcinogen N-methyl-N-nitrosourea (MNU). A single 50 mg/kg intraperitoneal dose of MNU resulted in a 60% incidence of premalignant mammary lesions, and a 20% incidence of mammary adenocarcinomas. Two cell lines, HMAM4A and HMAM4B, were derived from one of the primary mammary tumors induced by MNU. The morphology of the primary tumor was similar to a high-grade poorly differentiated adenocarcinoma in human breast cancer. The primary tumor stained positively for both HER-2/neu and pancytokeratin, and negatively for both cytokeratin 5/6 and p63. When the HMAM4B cell line was implanted subcutaneously into syngeneic female hamsters, tumors grew at a take rate of 50%. A tumor derived from HMAM4B cells implanted into a syngeneic hamster was further propagated in vitro as a stable cell line HMAM5. The HMAM5 cells grew in female syngeneic hamsters with a 70% take rate of tumor formation. These cells proliferate in vitro, form colonies in soft agar, and are aneuploid with a modal chromosomal number of 74 (the normal chromosome number for Syrian hamster is 44). To determine responsiveness to the estrogen receptor (ER), a cell proliferation assay was examined using increasing concentrations of tamoxifen. Both HMAM5 and human MCF-7 (ER positive) cells showed a similar decrease at 24 h. However, MDA-MB-231 (ER negative) cells were relatively insensitive to any decrease in proliferation from tamoxifen treatment. These results suggest that the HMAM5 cell line was likely derived from a luminal B subtype of mammary tumor. These results also represent characterization of the first mammary tumor cell line available from the Syrian hamster. The HMAM5 cell line is likely to be useful as an immunocompetent model for human breast cancer in developing novel therapies. PMID:21893382

  2. Establishment and characterization of a canine xenograft model of inflammatory mammary carcinoma.

    PubMed

    Camacho, L; Peña, L; González Gil, A; Cáceres, S; Díez, L; Illera, J C

    2013-12-01

    Canine inflammatory mammary cancer (IMC) and human inflammatory breast cancer (IBC) are the most aggressive form of mammary/breast cancer. Both species naturally develop it, sharing epidemiological, clinical and histological characteristics. Thus, IMC has been suggested as a model to study the human disease. We have developed the first IMC xenograft model in SCID mice. Xenografts reproduced the histological features from the primary tumor, were highly aggressive and showed dermal tumor emboli, distinctive hallmarks of IMC/IBC. This model was hormone receptors positive and HER2 negative. Our findings showed that estrogens and androgens are locally produced in tissues. Factors related to tumor vascularization showed positive expression and xenografts with the highest expression of all analyzed vascular factors had the highest rate of tumor proliferation. The role of steroid hormones and the angio/lymphangiogenic properties found in this model, provide additional knowledge for future interventions in the diagnosis, treatment and prevention of the disease.

  3. Inhibition of DMBA-induced mammary tumorigenesis by rosemary extract

    SciTech Connect

    Singletary, K. )

    1991-03-15

    Extracts of the spice, rosemary, have exhibited potent antioxidant properties. In order to evaluate the ability of rosemary extract to inhibit mammary tumorigenesis induced by 7,12-dimethylbenz(a)anthracene (DMBA), two groups of 32 day old female SD rats weighing 99.4 {plus minus} 2.6 g were fed semipurified diets containing either 0 or 1.0% rosemary extract during both the initiation and promotion stages of tumor development. All rats were administered DMBA at 53 days of age. Terminal tumor incidence was 75% and 40% for rats fed the 0 and 1.0% diets, respectively. Tumors/tumor-bearing rat were 2.3 {plus minus} 0.5 and 1.8 {plus minus} 0.3, respectively. In a second study 3 groups of female rats were fed diets containing 0, 0.5 or 1.0% rosemary extract for {minus}3 to +2 weeks following DMBA administration at 53 days of age. By 13 weeks post-DMBA tumor incidence for rats fed the 1.0% rosemary diet was significantly less than for rats fed the control diet. However, by 20, weeks, incidence for rats fed 0, 0.5, and 1.0% rosemary was 72.2, 69.6 and 58.3%, respectively. Tumors/tumor bearing rat were 2.2 {plus minus} 0.3, 2.0 {plus minus} 0.4 and 2.4 {plus minus} 0.5 for rats fed the 0, 0.5 and 1.0% diets, respectively. Therefore, rosemary extract can inhibit DMBA-induced mammary tumorigenesis when fed prior to and after DMBA dosing. Its antitumorigenic effect is not due to inhibition of the initiation stage alone.

  4. The effect of dietary zinc - and polyphenols intake on DMBA-induced mammary tumorigenesis in rats

    PubMed Central

    2012-01-01

    Background The aim of the study was to investigate the effect of dietary supplementation with zinc and polyphenol compounds, i.e. resveratrol and genistein, on the effectiveness of chemically induced mammary cancer and the changes in the content of selected elements (Zn, Cu, Mg, Fe, Ca) in tumors as compared with normal tissue of the mammary gland. Methods Female Sprague-Dawley rats were divided into study groups which, apart from the standard diet and DMBA (7,12-dimethyl-1,2- benz[a]anthracene), were treated with zinc ions (Zn) or zinc ions + resveratrol (Zn + resveratrol) or zinc ions + genistein (Zn + genistein) via gavage for a period from 40 days until 20 weeks of age. The ICP-OES (inductively coupled plasma optical emission spectrometry) technique was used to analyze the following elements: magnesium, iron, zinc and calcium. Copper content in samples was estimated in an atomic absorption spectrophotometer. Results Regardless of the diet (standard; Zn; Zn + resveratrol; Zn + genistein), DMBA-induced breast carcinogenesis was not inhibited. On the contrary, in the Zn + resveratrol supplemented group, tumorigenesis developed at a considerably faster rate. On the basis of quantitative analysis of selected elements we found - irrespectively of the diet applied - great accumulation of copper and iron, which are strongly prooxidative, with a simultaneous considerable decrease of the magnesium content in DMBA-induced mammary tumors. The combination of zinc supplementation with resveratrol resulted in particularly large differences in the amount of the investigated elements in tumors as compared with their content in normal tissue. Conclusions Diet supplementation with zinc and polyphenol compounds, i.e. resveratrol and genistein had no effect on the decreased copper level in tumor tissue and inhibited mammary carcinogenesis in the rat. Irrespectively of the applied diet, the development of the neoplastic process in rats resulted in changes of the iron and magnesium

  5. Elimination of progressive mammary cancer by repeated administrations of chimeric antigen receptor-modified T cells.

    PubMed

    Globerson-Levin, Anat; Waks, Tova; Eshhar, Zelig

    2014-05-01

    Continuous oncogenic processes that generate cancer require an on-going treatment approach to eliminate the transformed cells, and prevent their further development. Here, we studied the ability of T cells expressing a chimeric antibody-based receptor (CAR) to offer a therapeutic benefit for breast cancer induced by erbB-2. We tested CAR-modified T cells (T-bodies) specific to erbB-2 for their antitumor potential in a mouse model overexpressing a human erbB-2 transgene that develops mammary tumors. Comparing the antitumor reactivity of CAR-modified T cells under various therapeutic settings, either prophylactic, prior to tumor development, or therapeutically. We found that repeated administration of CAR-modified T cells is required to eliminate spontaneously developing mammary cancer. Systemic, as well as intratumoral administered CAR-modified T cells accumulated at tumor sites and eventually eliminated the malignant cells. Interestingly, within a few weeks after a single CAR T cells' administration, and rejection of primary lesion, tumors usually relapsed both in treated mammary gland and at remote sites; however, repeated injections of CAR-modified T cells were able to control the secondary tumors. Since spontaneous tumors can arise repeatedly, especially in the case of syndromes characterized by specific susceptibility to cancer, multiple administrations of CAR-modified T cells can serve to control relapsing disease.

  6. Magnetic field exposure increases cell proliferation but does not affect melatonin levels in the mammary gland of female Sprague Dawley rats.

    PubMed

    Fedrowitz, Maren; Westermann, Jürgen; Löscher, Wolfgang

    2002-03-01

    In line with the possible relationship between electric power and breast cancer risk as well as the underlying "melatonin hypothesis," we have shown previously (Thun-Battersby et al., Cancer Res., 59: 3627-3633, 1999) that 50-Hz magnetic fields (MFs) of low (100 microTesla) flux density enhance mammary gland tumor development and growth in the 7,12-dimethylbenz(a)anthracene model of breast cancer in female Sprague Dawley rats. On the basis of the melatonin hypothesis and previous observations of induction of ornithine decarboxylase in response to MF, we proposed that the effect of MF exposure on mammary carcinogenesis is related to enhanced proliferation of the mammary epithelium. The objective of the present study was to directly assess this proposal by the use of proliferation markers. Female Sprague Dawley rats were MF or sham exposed for 2 weeks at a flux density of 100 microTesla. Proliferation of epithelial cells in the mammary tissue and adjacent skin was examined by in vivo labeling of proliferating cells with bromodeoxyuridine (BrdUrd) and in situ labeling of the nuclear proliferation-associated Ki-67 protein by the antibody MIB-5. Furthermore, melatonin levels were determined after MF or sham exposure in the pineal gland and directly in the mammary tissue. In additional experiments, the tumor promoter 12-O-tetradecanoylphorbol-13-acetate was used for comparison with the effects of MF exposure. MF exposure significantly enhanced BrdUrd and Ki-67 labeling in the mammary epithelium, indicating a marked increase in cell proliferation. The most pronounced effect on proliferation was seen in the cranial thoracic (or cervical) mammary complexes, in which we previously had seen the most marked effects of MF exposure on mammary carcinogenesis. In contrast to the melatonin hypothesis, melatonin levels in pineal or mammary glands were not affected by MF exposure. Topical application of 12-O-tetradecanoylphorbol-13-acetate increased BrdUrd and Ki-67 labeling in

  7. Mammary Epithelial Cell Hierarchy in the Dairy Cow Throughout Lactation.

    PubMed

    Perruchot, Marie-Hélène; Arévalo-Turrubiarte, Magdalena; Dufreneix, Florence; Finot, Laurence; Lollivier, Vanessa; Chanat, Eric; Mayeur, Frédérique; Dessauge, Frédéric

    2016-10-01

    The plasticity of the mammary gland relies on adult mammary stem cells (MaSCs) and their progenitors, which give rise to various populations of mammary epithelial cells (MECs). To face global challenges, an in-depth characterization of milk-producing animal mammary gland plasticity is required, to select more sustainable and robust dairy cows. The identification and characterization of MaSC and their progenitors will also provide innovative tools in veterinary/human medicine regarding mammary tissue damage (carcinogenesis, bacterial infections). This study aimed to determine the dynamics of mammary cell populations throughout a lactation cycle. Using mammary biopsies from primiparous lactating dairy cows at 30, 90, 150, and 250 days of lactation, we phenotyped cell populations by flow cytometry. To investigate cell lineages, we used specific cell-surface markers, including CD49f, CD24, EpCAM (epithelial cell adhesion molecule), and CD10. Two cell populations linked to milk production were identified: CD49f(+)/EpCAM(-) (y = 0.88x + 4.42, R(2) = 0.36, P < 0.05) and CD49f(-)/EpCAM(-) (y = -1.15x + 92.44, R(2) = 0.51, P < 0.05) cells. Combining immunostaining analysis, flow cytometry, daily milk production data, and statistical approaches, we defined a stem cell population (CD24(+)/CD49f(+)) and four progenitor cell populations that include bipotent luminal progenitors (CD24(-)/CD49f(+)), lumino-alveolar progenitors (CD24(-)/EpCAM(+)), myoepithelial progenitors (CD24(+)/CD10(-)), and lumino-ductal progenitors (CD49f(-)/EpCAM(+)). Interestingly, we found that the bipotent luminal progenitors (CD24(-)/CD49f(+)) decreased significantly (P < 0.05) during lactation. This study provides the first results of mammary cell lineage, allowing insight into mammary cell plasticity during lactation.

  8. Mammary Epithelial Cell Hierarchy in the Dairy Cow Throughout Lactation.

    PubMed

    Perruchot, Marie-Hélène; Arévalo-Turrubiarte, Magdalena; Dufreneix, Florence; Finot, Laurence; Lollivier, Vanessa; Chanat, Eric; Mayeur, Frédérique; Dessauge, Frédéric

    2016-10-01

    The plasticity of the mammary gland relies on adult mammary stem cells (MaSCs) and their progenitors, which give rise to various populations of mammary epithelial cells (MECs). To face global challenges, an in-depth characterization of milk-producing animal mammary gland plasticity is required, to select more sustainable and robust dairy cows. The identification and characterization of MaSC and their progenitors will also provide innovative tools in veterinary/human medicine regarding mammary tissue damage (carcinogenesis, bacterial infections). This study aimed to determine the dynamics of mammary cell populations throughout a lactation cycle. Using mammary biopsies from primiparous lactating dairy cows at 30, 90, 150, and 250 days of lactation, we phenotyped cell populations by flow cytometry. To investigate cell lineages, we used specific cell-surface markers, including CD49f, CD24, EpCAM (epithelial cell adhesion molecule), and CD10. Two cell populations linked to milk production were identified: CD49f(+)/EpCAM(-) (y = 0.88x + 4.42, R(2) = 0.36, P < 0.05) and CD49f(-)/EpCAM(-) (y = -1.15x + 92.44, R(2) = 0.51, P < 0.05) cells. Combining immunostaining analysis, flow cytometry, daily milk production data, and statistical approaches, we defined a stem cell population (CD24(+)/CD49f(+)) and four progenitor cell populations that include bipotent luminal progenitors (CD24(-)/CD49f(+)), lumino-alveolar progenitors (CD24(-)/EpCAM(+)), myoepithelial progenitors (CD24(+)/CD10(-)), and lumino-ductal progenitors (CD49f(-)/EpCAM(+)). Interestingly, we found that the bipotent luminal progenitors (CD24(-)/CD49f(+)) decreased significantly (P < 0.05) during lactation. This study provides the first results of mammary cell lineage, allowing insight into mammary cell plasticity during lactation. PMID:27520504

  9. Analysis of Gene Expression in PTHrP−/− Mammary Buds Supports a Role for BMP Signaling and MMP2 in the Initiation of Ductal Morphogenesis

    PubMed Central

    Hens, Julie; Dann, Pamela; Hiremath, Minoti; Pan, Tien-Chi; Chodosh, Lewis; Wysolmerski, John

    2010-01-01

    Parathyroid hormone-related protein (PTHrP) acts on the mammary mesenchyme and is required for proper embryonic mammary development. In order to understand PTHrP’s effects on mesenchymal cells, we profiled gene expression in WT and PTHrP−/− mammary buds, and in WT and K14-PTHrP ventral skin at E15.5. By cross-referencing the differences in gene expression between these groups, we identified 35 genes potentially regulated by PTHrP in the mammary mesenchyme, including 6 genes known to be involved in BMP signaling. One of these genes was MMP2. We demonstrated that PTHrP and BMP4 regulate MMP2 gene expression and MMP2 activity in mesenchymal cells. Using mammary bud cultures, we demonstrated that MMP2 acts downstream of PTHrP to stimulate ductal outgrowth. Future studies on the functional role of other genes on this list should expand our knowledge of how PTHrP signaling triggers the onset of ductal outgrowth from the embryonic mammary buds. PMID:19795511

  10. Maternal high fat diet promotion of mammary tumor risk in adult progeny is associated with early expansion of mammary cancer stem-like cells and increased maternal oxidative environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many adult chronic diseases might be programmed during early life by maternal nutritional history. Here, we evaluated effects of maternal high fat diet on mammary gland development and tumor formation in adult progeny. Female Wnt-1 transgenic mice exposed to high fat (HFD, 45% kcal fat) or control C...

  11. Dietary genistein results in larger MNU-induced, estrogen-dependent mammary tumors following ovariectomy of Sprague-Dawley rats.

    PubMed

    Allred, Clinton D; Allred, Kimberly F; Ju, Young H; Clausen, Laura M; Doerge, Daniel R; Schantz, Susan L; Korol, Donna L; Wallig, Matthew A; Helferich, William G

    2004-02-01

    Due to the estrogenic properties of soy-derived isoflavones, many postmenopausal women are using these compounds as a natural alternative to hormone replacement therapy (HRT). How isoflavones impact breast cancer in postmenopausal women is important, because a majority of breast cancer cases occur in this age group. Chemical induction of mammary tumors in female rats has been used to determine that exposure of the mammary gland to soy isoflavones prior to tumor induction is protective against tumor formation. Here we investigate the effect of dietary genistein on mammary tumors that have already formed. The study was designed to determine the action of dietary genistein in a low endogenous estrogen environment as is observed in postmenopausal women. Animals were ovariectomized (OVX) after mammary tumor development and were then placed into one of three treatment groups: positive-control (OVX+ estradiol implant), genistein (OVX+ 750 p.p.m. genistein) and negative-control (OVX alone). Tumors were distinguished as malignant or benign by histopathological examination and were further characterized as either estrogen-dependent or estrogen-independent using immunohistochemistry to identify the presence of both estrogen receptor (ER) alpha and the progesterone receptor (PR). Genistein at 750 p.p.m. increased the weight of estrogen-dependent adenocarcinomas in ovariectomized rats compared with the negative-control animals. Genistein treatment also resulted in a higher percentage of proliferative cells in tumors and increased uterine weights when compared with negative-control animals. Collectively, these effects are probably due to the estrogenic activity of genistein. Plasma genistein concentrations in animals fed the isoflavone-containing diet were at physiological levels relevant to human exposure. Estradiol concentrations in ovariectomized animals not receiving an estradiol supplement were similar to those observed in postmenopausal women. The data suggest that in an

  12. A new technique for repeated biopsies of the mammary gland in dairy cows allotted to Latin-square design studies.

    PubMed

    de Lima, Luciano S; Martineau, Eric; De Marchi, Francilaine E; Palin, Marie-France; Dos Santos, Geraldo T; Petit, Hélène V

    2016-07-01

    The objective of this study was to develop a technique for carrying out repeated biopsies of the mammary gland of lactating dairy cows that provides enough material to monitor enzyme activities and gene expression in mammary secretory tissue. A total of 16 Holstein cows were subjected to 4 mammary biopsies each at 3-week intervals for a total of 64 biopsies. A 0.75-cm incision was made through the skin and subcutaneous tissue of the mammary gland and a trocar and cannula were inserted using a circular motion. The trocar was withdrawn and a syringe was plugged into the base of the cannula to create a vacuum for sampling mammary tissue. To reduce bleeding, hand pressure was put on the surgery site after biopsy and skin closure and ice was applied for at least 2 h after the biopsy using a cow bra. The entire procedure took an average of 25 min. Two attempts were usually enough to obtain 800 mg of tissue. Visual examination of milk samples 10 d after the biopsy indicated no trace of blood, except in samples from 2 cows. All wounds healed without infection and subcutaneous hematomas resorbed within 7 d. There was no incidence of mastitis throughout the lactation. This technique provides a new tool for biopsy of the mammary gland repeated at short intervals with the main effect being a decrease in milk production. Although secondary complications leading to illness or death are always a risk with any procedure, this biopsy technique was carried out without complications to the health of animals and with no incidence of mastitis during the lactation. PMID:27408336

  13. A new technique for repeated biopsies of the mammary gland in dairy cows allotted to Latin-square design studies.

    PubMed

    de Lima, Luciano S; Martineau, Eric; De Marchi, Francilaine E; Palin, Marie-France; Dos Santos, Geraldo T; Petit, Hélène V

    2016-07-01

    The objective of this study was to develop a technique for carrying out repeated biopsies of the mammary gland of lactating dairy cows that provides enough material to monitor enzyme activities and gene expression in mammary secretory tissue. A total of 16 Holstein cows were subjected to 4 mammary biopsies each at 3-week intervals for a total of 64 biopsies. A 0.75-cm incision was made through the skin and subcutaneous tissue of the mammary gland and a trocar and cannula were inserted using a circular motion. The trocar was withdrawn and a syringe was plugged into the base of the cannula to create a vacuum for sampling mammary tissue. To reduce bleeding, hand pressure was put on the surgery site after biopsy and skin closure and ice was applied for at least 2 h after the biopsy using a cow bra. The entire procedure took an average of 25 min. Two attempts were usually enough to obtain 800 mg of tissue. Visual examination of milk samples 10 d after the biopsy indicated no trace of blood, except in samples from 2 cows. All wounds healed without infection and subcutaneous hematomas resorbed within 7 d. There was no incidence of mastitis throughout the lactation. This technique provides a new tool for biopsy of the mammary gland repeated at short intervals with the main effect being a decrease in milk production. Although secondary complications leading to illness or death are always a risk with any procedure, this biopsy technique was carried out without complications to the health of animals and with no incidence of mastitis during the lactation.

  14. Extra-mammary findings on breast MRI: a pictorial review.

    PubMed

    Karp, Norna L; Price, Elissa R; Wisner, Dorota J; Chang, C Belinda; Hylton, Nola M; Joe, Bonnie N

    2015-01-01

    Recent improvements in breast coil performance have made detection of extra-mammary findings increasingly common. Some of these findings have important clinical implications. The radiologist should be aware of the spectrum of extra-mammary pathologies found on breast magnetic resonance imaging (MRI) and be able to distinguish clinically significant findings from those that are inconsequential. The purpose of this essay is to demonstrate various common and uncommon extra-mammary findings encountered while interpreting breast MRI and to detail appropriate management recommendations.

  15. Polypeptide N-acetylgalactosaminyltransferase 6 disrupts mammary acinar morphogenesis through O-glycosylation of fibronectin.

    PubMed

    Park, Jae-Hyun; Katagiri, Toyomasa; Chung, Suyoun; Kijima, Kyoko; Nakamura, Yusuke

    2011-04-01

    A high expression of short and immature O-glycans is one of the prominent features of breast cancer cells, which would be attributed to the upregulated expression of glycosyltransferases. Therefore, a detailed elucidation of glycosyltransferases and their substrate(s) may improve our understandings for their roles in mammary carcinogenesis. Here we report that overexpression of polypeptide N-acetylgalactosaminyltransferase 6 (GALNT6), a glycosyltransferase involved in the initial step of O-glycosylation, has transformational potentials through disruptive acinar morphogenesis and cellular changes similar to epithelial-to-mesenchymal transition in normal mammary epithelial cell, MCF10A. As one of the critical O-glycan substrates, we identified fibronectin that was O-glycosylated in vivo and thereby stabilized by GALNT6. Because knockdown of fibronectin abrogated the disruptive proliferation caused by introduction of GALNT6 into epithelial cells, our findings suggest that GALNT6-fibronectin pathway should be a critical component for breast cancer development and progression.

  16. Extracellular matrix proteins regulate epithelial-mesenchymal transition in mammary epithelial cells

    PubMed Central

    Chen, Qike K.; Lee, KangAe; Radisky, Derek C.; Nelson, Celeste M.

    2013-01-01

    Mouse mammary epithelial cells undergo transdifferentiation via epithelial-mesenchymal transition (EMT) upon treatment with matrix metalloproteinase-3 (MMP3). In rigid microenvironments, MMP3 upregulates expression of Rac1b, which translocates to the cell membrane to promote induction of reactive oxygen species and EMT. Here we examine the role of the extracellular matrix (ECM) in this process. Our data show that the basement membrane protein laminin suppresses the EMT response in MMP3-treated cells, whereas fibronectin promotes EMT. These ECM proteins regulate EMT via interactions with their specific integrin receptors. α6-integrin sequesters Rac1b from the membrane and is required for inhibition of EMT by laminin. In contrast, α5-integrin maintains Rac1b at the membrane and is required for the promotion of EMT by fibronectin. Understanding the regulatory role of the ECM will provide insight into mechanisms underlying normal and pathological development of the mammary gland. PMID:23660532

  17. Effects of sodium butyrate on expression of members of the IGF-binding protein superfamily in human mammary epithelial cells.

    PubMed

    Tsubaki, J; Choi, W K; Ingermann, A R; Twigg, S M; Kim, H S; Rosenfeld, R G; Oh, Y

    2001-04-01

    Dietary factors play an important role in both the development and prevention of human cancers, including breast carcinoma. One dietary micronutrient, sodium butyrate (NaB), is a major end product of dietary starch and fiber, produced naturally during digestion by anaerobic bacteria in the cecum and colon. NaB is a potent growth inhibitor and initiates cell differentiation for many cell types in vitro. In this study, we investigated the effects of NaB on three human mammary epithelial cells and regulation of the IGF axis, specifically, IGF-binding protein-3 (IGFBP-3), a known growth regulator in human mammary cells, and IGFBP-related protein 2 (IGFBP-rP2)/connective tissue growth factor. NaB inhibited DNA synthesis, as measured by [3H]thymidine incorporation, in estrogen-responsive (MCF-7) and estrogen-non-responsive (Hs578T) breast cancer cells, and normal human mammary epithelial cells (HMEC) to a similar degree (up to 90% inhibition at 1-10 mM concentrations). Treatment of cells with NaB induced histone hyperacetylation, suggesting that NaB exerts its biological effects, at least in part, as a histone deacetylase inhibitor in mammary epithelial cells. Treatment of Hs578T cells with NaB caused an induction of apoptotic cell death. NaB treatment resulted in increased levels of p21(Waf1/Cip1) mRNA and protein in Hs578T cells and distinct upregulation of p27(Kip1) in HMEC, suggesting that NaB activates different genes involved in cell cycle arrest, depending upon the cell type. In the same context, among the IGFBP superfamily members tested, NaB specifically upregulated the expression of IGFBP-3 and IGFBP-rP2. These two proteins are known to be involved in inhibition of mammary epithelial cell replication. Northern blot analysis showed that NaB treatment at 1-10 mM concentrations caused a dose-dependent stimulation of IGFBP-3 mRNA expression in cancerous cells and IGFBP-rP2 mRNA expression in both cancerous and non-cancerous cells. Protein data from Western ligand

  18. Asymmetric Expression of Connexins between luminal epithelial- and myoepithelial- cells is Essential for Contractile Function of the Mammary Gland

    PubMed Central

    Mroue, Rana; Inman, Jamie; Mott, Joni; Budunova, Irina; Bissell, Mina J.

    2016-01-01

    Intercellular communication is essential for glandular functions and tissue homeostasis. Gap junctions couple cells homotypically and heterotypically and coordinate reciprocal responses between the different cell types. Connexins (Cxs) are the main mammalian gap junction proteins, and the distribution of some Cx subtypes in the heterotypic gap junctions is not symmetrical; in the murine mammary gland, Cx26, Cx30 and Cx32 are expressed only in the luminal epithelial cells and Cx43 is expressed only in myoepithelial cells. Expression of all four Cxs peaks during late pregnancy and throughout lactation suggesting essential roles for these proteins in the functional secretory activity of the gland. Transgenic (Tg) mice over-expressing Cx26 driven by keratin 5 promoter had an unexpected mammary phenotype: the mothers were unable to feed their pups to weaning age leading to litter starvation and demise in early to mid-lactation. The mammary gland of K5-Cx26 female mice developed normally and produced normal levels of milk protein, suggesting a defect in delivery rather than milk production. Because the mammary gland of K5-Cx26 mothers contained excessive milk, we hypothesized that the defect may be in an inability to eject the milk. Using ex vivo three-dimensional mammary organoid cultures, we showed that tissues isolated from wild-type FVB females contracted upon treatment with oxytocin, whereas, organoids from Tg mice failed to do so. Unexpectedly, we found that ectopic expression of Cx26 in myoepithelial cells altered the expression of endogenous Cx43 resulting in impaired gap junction communication, demonstrated by defective dye coupling in mammary epithelial cells of Tg mice. Inhibition of gap junction communication or knock-down of Cx43 in organoids from wild-type mice impaired contraction in response to oxytocin, recapitulating the observations from the mammary glands of Tg mice. We conclude that Cx26 acts as a trans-dominant negative for Cx43 function in

  19. Cleavage of Histone 3 by Cathepsin D in the Involuting Mammary Gland

    PubMed Central

    Khalkhali-Ellis, Zhila; Goossens, William; Margaryan, Naira V.; Hendrix, Mary J. C.

    2014-01-01

    The post-lactational regression of mammary gland is a complex multi-step process designed to conserve the biological function of the gland for next pregnancy. This developmental stage is a biological intrigue with great relevance to breast cancer research, and thus has been the subject of intensive scrutiny. Multipronged studies (microarray, proteomics profiling, animal knock-out models) have provided a repertoire of genes critical to involution. However, the caveat of these approaches remains in their failure to reveal post-translational modification(s), an emerging and critical aspect of gene regulation in developmental processes and mammary gland remodeling. The massive surge in the lysosomal enzymes concurrent with the onset of involution has been known for decades, and considered essential for “clearance” purposes. However, functional significance of these enzymes in diverse biological processes distinct from their proteolytic activity is just emerging. Studies from our laboratory had indicated specific post-translational modifications of the aspartyl endopeptidase Cathepsin D (CatD) at distinct stages mammary gland development. This study addresses the biological significance of these modifications in the involution process, and reveals that post-translational modifications drive CatD into the nucleus to cleave Histone 3. The cleavage of Histone 3 has been associated with cellular differentiation and could be critical instigator of involution process. From functional perspective, deregulated expression and increased secretion of CatD are associated with aggressive and metastatic phenotype of breast cancer. Thus unraveling CatD’s physiological functions in mammary gland development will bridge the present gap in understanding its pro-tumorigenic/metastatic functions, and assist in the generation of tailored therapeutic approaches. PMID:25054204

  20. Use of Three-Dimensional Basement Membrane Cultures to Model Oncogene-Induced Changes in Mammary Epithelial Morphogenesis

    PubMed Central

    Mills Shaw, Kenna R.; Wrobel, Carolyn N.; Brugge, Joan S.

    2005-01-01

    The development of breast carcinomas involves a complex set of phenotypic alterations in breast epithelial cells and the surrounding microenvironment. While traditional transformation assays provide models for investigating certain aspects of the cellular processes associated with tumor initiation and progression, they do not model alterations in tissue architecture that are critically involved in tumor development. In this review, we provide examples of how three-dimensional (3D) cell culture models can be utilized to dissect the pathways involved in the development of mammary epithelial structures and to elucidate the mechanisms responsible for oncogene-induced phenotypic alterations in epithelial behavior and architecture. Many normal mammary epithelial cell lines undergo a stereotypic morphogenetic process when grown in the presence of exogenous matrix proteins. This 3D morphogenesis culminates in the formation of well-organized, polarized spheroids, and/or tubules that are highly reminiscent of normal glandular architecture. In contrast, transformed cell lines isolated from mammary tumors exhibit significant deviations from normal epithelial behavior in 3D culture. We describe the use of 3D models as a method for both reconstructing and deconstructing the cell biological and biochemical events involved in mammary neoplasia. PMID:15838601

  1. Genomic and Phenomic Study of Mammary Pathogenic Escherichia coli

    PubMed Central

    Blum, Shlomo E.; Heller, Elimelech D.; Sela, Shlomo; Elad, Daniel; Edery, Nir; Leitner, Gabriel

    2015-01-01

    Escherichia coli is a major etiological agent of intra-mammary infections (IMI) in cows, leading to acute mastitis and causing great economic losses in dairy production worldwide. Particular strains cause persistent IMI, leading to recurrent mastitis. Virulence factors of mammary pathogenic E. coli (MPEC) involved pathogenesis of mastitis as well as those differentiating strains causing acute or persistent mastitis are largely unknown. This study aimed to identify virulence markers in MPEC through whole genome and phenome comparative analysis. MPEC strains causing acute (VL2874 and P4) or persistent (VL2732) mastitis were compared to an environmental strain (K71) and to the genomes of strains representing different E. coli pathotypes. Intra-mammary challenge in mice confirmed experimentally that the strains studied here have different pathogenic potential, and that the environmental strain K71 is non-pathogenic in the mammary gland. Analysis of whole genome sequences and predicted proteomes revealed high similarity among MPEC, whereas MPEC significantly differed from the non-mammary pathogenic strain K71, and from E. coli genomes from other pathotypes. Functional features identified in MPEC genomes and lacking in the non-mammary pathogenic strain were associated with synthesis of lipopolysaccharide and other membrane antigens, ferric-dicitrate iron acquisition and sugars metabolism. Features associated with cytotoxicity or intra-cellular survival were found specifically in the genomes of strains from severe and acute (VL2874) or persistent (VL2732) mastitis, respectively. MPEC genomes were relatively similar to strain K-12, which was subsequently shown here to be possibly pathogenic in the mammary gland. Phenome analysis showed that the persistent MPEC was the most versatile in terms of nutrients metabolized and acute MPEC the least. Among phenotypes unique to MPEC compared to the non-mammary pathogenic strain were uric acid and D-serine metabolism. This study

  2. Internal mammary silicone lymphadenopathy diagnosed by robotic thoracoscopic lymphadenectomy.

    PubMed

    Schwartz, Gary S; Antoun, David; Klein, Paula; Belsley, Scott J; Connery, Cliff P

    2013-06-01

    Internal mammary lymphadenopathy can be caused by a variety of disease processes and is a difficult diagnostic dilemma. We report a case of internal mammary lymphadenopathy, in a patient with a significant history of malignancy, requiring a tissue diagnosis. Robotic thoracoscopic lymphadenectomy was used to facilitate excisional biopsy. Pathology was significant for silicone granulomatous lymphadenitis secondary to silicone breast implants inserted after mastectomy for breast cancer. PMID:27000915

  3. Genomic and Phenomic Study of Mammary Pathogenic Escherichia coli.

    PubMed

    Blum, Shlomo E; Heller, Elimelech D; Sela, Shlomo; Elad, Daniel; Edery, Nir; Leitner, Gabriel

    2015-01-01

    Escherichia coli is a major etiological agent of intra-mammary infections (IMI) in cows, leading to acute mastitis and causing great economic losses in dairy production worldwide. Particular strains cause persistent IMI, leading to recurrent mastitis. Virulence factors of mammary pathogenic E. coli (MPEC) involved pathogenesis of mastitis as well as those differentiating strains causing acute or persistent mastitis are largely unknown. This study aimed to identify virulence markers in MPEC through whole genome and phenome comparative analysis. MPEC strains causing acute (VL2874 and P4) or persistent (VL2732) mastitis were compared to an environmental strain (K71) and to the genomes of strains representing different E. coli pathotypes. Intra-mammary challenge in mice confirmed experimentally that the strains studied here have different pathogenic potential, and that the environmental strain K71 is non-pathogenic in the mammary gland. Analysis of whole genome sequences and predicted proteomes revealed high similarity among MPEC, whereas MPEC significantly differed from the non-mammary pathogenic strain K71, and from E. coli genomes from other pathotypes. Functional features identified in MPEC genomes and lacking in the non-mammary pathogenic strain were associated with synthesis of lipopolysaccharide and other membrane antigens, ferric-dicitrate iron acquisition and sugars metabolism. Features associated with cytotoxicity or intra-cellular survival were found specifically in the genomes of strains from severe and acute (VL2874) or persistent (VL2732) mastitis, respectively. MPEC genomes were relatively similar to strain K-12, which was subsequently shown here to be possibly pathogenic in the mammary gland. Phenome analysis showed that the persistent MPEC was the most versatile in terms of nutrients metabolized and acute MPEC the least. Among phenotypes unique to MPEC compared to the non-mammary pathogenic strain were uric acid and D-serine metabolism. This study

  4. Two monoclonal antibodies selective for human mammary carcinoma.

    PubMed

    White, C A; Dulbecco, R; Allen, R; Bowman, M; Armstrong, B

    1985-03-01

    Mouse myeloma cells were fused with spleen cells from BALB/c mice immunized with the MCF-7 human mammary carcinoma cell line. Among hybridomas, two (3B18 and 15A8) were selected and cloned. Hybridoma 3B18 produces kappa-IgG1 antibodies that react with a cytoplasmic component of MCF-7 cells. In immunoperoxidase assays, 3B18 reacts with 27 of 31 specimens of human mammary carcinoma. It reacts most consistently with poorly differentiated and infiltrating ductal breast cancers, but it also reacts with isolated cells in 3 of 5 benign mammary pathological lesions with a variable distribution. The antibody does not react with normal mammary epithelium. It does not react with any normal human tissues, and it reacts with only one of 19 other cancers tested. Hybridoma 15A8 produces kappa-IgG1 antibodies that react with the surface membranes of the cells of two human breast cancer cell lines but not with a human fibroblast cell line. In immunoperoxidase assays, the antibody reacted with 28 out of 31 human mammary carcinomas. The antibody also reacts more weakly with normal human epithelial cells of breast, renal proximal tubule, skin, esophagus, and salivary gland, but no other normal tissue. The antibody was unreactive with 14 of 18 other malignant tissues tested. Since 3B18 and 15A8 detect antigens found predominantly in human mammary carcinomas and, possibly, distinguish overlapping categories of human mammary carcinomas, they may prove useful in determining the cellular lineage from which human mammary carcinomas arise, or they may have other clinical applications in breast cancer.

  5. The role of tight junctions in mammary gland function.

    PubMed

    Stelwagen, Kerst; Singh, Kuljeet

    2014-03-01

    Tight junctions (TJ) are cellular structures that facilitate cell-cell communication and are important in maintaining the three-dimensional structure of epithelia. It is only during the last two decades that the molecular make-up of TJ is becoming unravelled, with two major transmembrane-spanning structural protein families, called occludin and claudins, being the true constituents of the TJ. These TJ proteins are linked via specific scaffolding proteins to the cell's cytoskeleton. In the mammary gland TJ between adjacent secretory epithelial cells are formed during lactogenesis and are instrumental in establishing and maintaining milk synthesis and secretion, whereas TJ integrity is compromised during mammary involution and also as result of mastitis and periods of mammary inflamation (including mastitis). They prevent the paracellular transport of ions and small molecules between the blood and milk compartments. Formation of intact TJ at the start of lactation is important for the establishment of the lactation. Conversely, loss of TJ integrity has been linked to reduced milk secretion and mammary function and increased paracellular transport of blood components into the milk and vice versa. In addition to acting as a paracellular barrier, the TJ is increasingly linked to playing an active role in intracellular signalling. This review focusses on the role of TJ in mammary function of the normal, non-malignant mammary gland, predominantly in ruminants, the major dairy producing species.

  6. Mast cells in canine cutaneous hemangioma, hemangiosarcoma and mammary tumors.

    PubMed

    Woldemeskel, Moges; Rajeev, Sreekumari

    2010-02-01

    Mast cell count (MCC) in 45 dogs with cutaneous hemangioma (HA, n = 12), hemangiosarcoma (HSA, n = 12), mammary adenoma (AD, n = 9) and mammary adenocarcinoma (AC, n = 12) was made using Toluidine blue stained sections. Antibodies against endothelial cell markers, Factor VIII and VEGF were used to visualize and determine the hot spot micro-vessel density (MVD). Total MCC and MCC along the invasive edges were significantly higher (p < 0.001) in canine mammary AC than in AD. The total MCC did not significantly differ (p > 0.05), in HSAs (8.6 +/- 3.3) than in HAs (5.5 +/- 2.8). There is a positive correlation (r = 0.14) between the hot spot MCC and MVD in mammary AC, although not significant (p = 0.3172), indicating that mast cells are associated with angiogenesis in canine mammary AC. This study suggests that mast cells may play an important role in neovascularization of canine cutaneous vascular and mammary neoplasms. Detailed studies encompassing correlation of MCC and MVD with clinical outcomes and prognosis in these neoplasms are recommended.

  7. Influence of lithium on mammary tumor growth in vivo.

    PubMed

    Ziche, M; Maiorana, A; Oka, T; Gullino, P M

    1980-05-01

    The possibility that lithium ions stimulate growth of mammary tumors in vivo has been suggested by their mitogenic action in vitro on normal and neoplastic mammary epithelium [8] and their clinical use as stimulators of neutrophil production in tumor-bearing patients treated with cytotoxic drugs [14,15]. Three experiments were performed to assess this possibility. Buffalo/N female rats received a single injection of N-nitrosomethylurea (NMU) at a dose known to produce mammary carcinomas in about 50% of animals under standard conditions. Under lithium treatment, the incidence of tumors did not increase significantly. Sprague-Dawley female rats treated with a single dose of 7,12-dimethylbenz[alpha] anthracene (DMBA), but showing no mammary tumors after 4 months, received lithium in their drinking water for 3 additional months. The number of late-appearing tumors was not increased by lithium treatment. Buffalo/N females with NMU-induced tumors were castrated, and the subsequent changes in tumor volume were compared in lithium-treated and control animals. The regression-regrowth curves were not altered by lithium treatment. These results are in contrast to the growth stimulatory capacity of lithium on mammary epithelium observed in vitro [8] and indicate it is very unlikely that lithium ions have an undesirable growth stimulatory action on primary mammary carcinomas in vivo.

  8. The prolactin receptor mediates HOXA1-stimulated oncogenicity in mammary carcinoma cells.

    PubMed

    Hou, Lin; Xu, Bing; Mohankumar, Kumarasamypet M; Goffin, Vincent; Perry, Jo K; Lobie, Peter E; Liu, Dong-Xu

    2012-12-01

    The HOX genes are a highly conserved subgroup of homeodomain-containing transcription factors that are crucial to normal development. Forced expression of HOXA1 results in oncogenic transformation of immortalized human mammary cells with aggressive tumour formation in vivo. Microarray analysis identified that the prolactin receptor (PRLR) was significantly upregulated by forced expression of HOXA1 in mammary carcinoma cells. To determine prolactin (PRL) involvement in HOXA1‑induced oncogenicity in mammary carcinoma cells (MCF-7), we examined the effect of human prolactin (hPRL)-initiated PRLR signal transduction on changes in cellular behaviour mediated by HOXA1. Forced expression of HOXA1 in MCF-7 cells increased PRLR mRNA and protein expression. Forced expression of HOXA1 also enhanced hPRL-stimulated phosphorylation of both STAT5A/B and p44/42 MAPK, and increased subsequent transcriptional activity of STAT5A and STAT5B, and Elk-1 and Sap1a, respectively. Moreover, forced expression of HOXA1 in MCF-7 cells enhanced the hPRL‑stimulated increase in total cell number as a consequence of enhanced cell proliferation and cell survival, and also enhanced hPRL-stimulated anchorage-independent growth in soft agar. Increased anchorage-independent growth was attenuated by the PRLR antagonist ∆1-9-G129R‑hPRL. In conclusion, we have demonstrated that HOXA1 increases expression of the cell surface receptor PRLR and enhances PRLR-mediated signal transduction. Thus, the PRLR is one mediator of HOXA1‑stimulated oncogenicity in mammary carcinoma cells. PMID:23064471

  9. Computational identification and characterization of novel microRNA in the mammary gland of dairy goat (Capra hircus).

    PubMed

    Qu, Bo; Qiu, Youwen; Zhen, Zhen; Zhao, Feng; Wang, Chunmei; Cui, Yingjun; Li, Qizhang; Zhang, Li

    2016-09-01

    Many studies have indicated that microRNAs (miRNAs) influence the development of the mammary gland by posttranscriptionally affecting their target genes. The objective of this research was to identify novel miRNAs in the mammary gland of dairy goats with a bioinformatics approach that was based on expressed sequence tag (EST) and genome survey sequence (GSS) analyses. We applied all known major mammals, miRNAs to search against the goat EST and GSS databases for the first time to identify new miRNAs. We, then, validated these newly predicted miRNAs with stem-loop reverse transcription followed by a SYBR Green polymerase chain reaction assay. Finally, 29 mature miRNAs were identified and verified, and of these, 14 were grouped into 13 families based on seed sequence identity and 85 potential target genes of newly verified miRNAs were subsequently predicted, most of which seemed to encode the proteins participating in regulation of metabolism, signal transduction, growth and development. The predicting accuracy of the new miRNAs was 70.37%, which confirmed that the methods used in this study were efficient and reliable. Detailed analyses of the sequence characteristics of the novel miRNAs of the goat mammary gland were performed. In conclusion, these results provide a reference for further identification of miRNAs in animals without a complete genome and thus improve the understanding of miRNAs in the caprine mammary gland. PMID:27659334

  10. c-myc as a mediator of accelerated apoptosis and involution in mammary glands lacking Socs3

    PubMed Central

    Sutherland, Kate D; Vaillant, François; Alexander, Warren S; Wintermantel, Tim M; Forrest, Natasha C; Holroyd, Sheridan L; McManus, Edward J; Schutz, Gunther; Watson, Christine J; Chodosh, Lewis A; Lindeman, Geoffrey J; Visvader, Jane E

    2006-01-01

    Suppressor of cytokine signalling (SOCS) proteins are critical attenuators of cytokine-mediated signalling in diverse tissues. To determine the importance of Socs3 in mammary development, we generated mice in which Socs3 was deleted in mammary epithelial cells. No overt phenotype was evident during pregnancy and lactation, indicating that Socs3 is not a key physiological regulator of prolactin signalling. However, Socs3-deficient mammary glands exhibited a profound increase in epithelial apoptosis and tissue remodelling, resulting in precocious involution. This phenotype was accompanied by augmented Stat3 activation and a marked increase in the level of c-myc. Moreover, induction of c-myc before weaning using an inducible transgenic model recapitulated the Socs3 phenotype, and elevated expression of likely c-myc target genes, E2F-1, Bax and p53, was observed. Our data establish Socs3 as a critical attenuator of pro-apoptotic pathways that act in the developing mammary gland and provide evidence that c-myc regulates apoptosis during involution. PMID:17139252

  11. Laminin and biomimetic extracellular elasticity enhance functional differentiation in mammary epithelia

    SciTech Connect

    Alcaraz, Jordi; Xu, Ren; Mori, Hidetoshi; Nelson, Celeste M.; Mroue, Rana; Spencer, Virginia A.; Brownfield, Doug; Radisky, Derek C.; Bustamante, Carlos; Bissell, Mina J.

    2008-10-20

    In the mammary gland, epithelial cells are embedded in a 'soft' environment and become functionally differentiated in culture when exposed to a laminin-rich extracellular matrix gel. Here, we define the processes by which mammary epithelial cells integrate biochemical and mechanical extracellular cues to maintain their differentiated phenotype. We used single cells cultured on top of gels in conditions permissive for {beta}-casein expression using atomic force microscopy to measure the elasticity of the cells and their underlying substrata. We found that maintenance of {beta}-casein expression required both laminin signalling and a 'soft' extracellular matrix, as is the case in normal tissues in vivo, and biomimetic intracellular elasticity, as is the case in primary mammary epithelial organoids. Conversely, two hallmarks of breast cancer development, stiffening of the extracellular matrix and loss of laminin signalling, led to the loss of {beta}-casein expression and non-biomimetic intracellular elasticity. Our data indicate that tissue-specific gene expression is controlled by both the tissues unique biochemical milieu and mechanical properties, processes involved in maintenance of tissue integrity and protection against tumorigenesis.

  12. Luminal Epithelial Cells within the Mammary Gland Can Produce Basal Cells upon Oncogenic Stress

    PubMed Central

    Hein, Sarah M.; Haricharan, Svasti; Johnston, Alyssa N.; Toneff, Michael J.; Reddy, Jay P.; Dong, Jie; Bu, Wen; Li, Yi

    2015-01-01

    In the normal mammary gland, the basal epithelium is known to be bi-potent and can generate either basal or luminal cells, whereas the luminal epithelium has not been demonstrated to contribute to the basal compartment in an intact and normally developed mammary gland. It is not clear whether cellular heterogeneity within a breast tumor results from transformation of bi-potent basal cells or from transformation and subsequent basal conversion of the more differentiated luminal cells. Here, we used a retroviral vector to express an oncogene specifically in a small number of the mammary luminal epithelial cells and tested their potential to produce basal cells during tumorigenesis. This in vivo lineage tracing work demonstrates that luminal cells are capable of producing basal cells upon activation of either Polyoma Middle T antigen (PyMT) or ErbB2 signaling. These findings reveal the plasticity of the luminal compartment during tumorigenesis and provide an explanation for cellular heterogeneity within a cancer. PMID:26096929

  13. Regulatory role for amino acids in mammary gland growth and milk synthesis.

    PubMed

    Kim, Sung Woo; Wu, Guoyao

    2009-05-01

    The health and growth of mammalian neonates critically depend on the yield and composition of their mothers' milk. However, impaired lactogenesis occurs in both women in response to stress and hormonal imbalance and in primiparous sows which exhibit low voluntary feed intake and underdevelopment of mammary tissues. Because of ethical concerns over lactation research with women and children, swine is often used as an animal model to study mammary gland development and the underlying regulatory mechanisms. Available evidence from work with lactating sows shows that amino acids are not only building blocks for protein but are also key regulators of metabolic pathways critical to milk production. Particularly, arginine is the common substrate for the generation of nitric oxide (NO; a major vasodilator and angiogenic factor) and polyamines (key regulators of protein synthesis). Thus, modulation of the arginine-NO pathway may provide a new strategy to enhance the growth (including vascular growth) of mammary tissue and its uptake of nutrients, therefore improving lactation performance in mammals. In support of this proposition, supplementing 0.83% L: -arginine (as 1% L: -arginine-HCl) or 50 mg/day diethylenetriamine-NO adduct (NO donor) to diets of lactating primiparous sows increased milk production and the growth of suckling piglets. Future studies with animal models (e.g., pigs, sheep, cows, and rats) are necessary to elucidate the underlying mechanisms at molecular, cellular, tissue, and whole-body levels. PMID:18683019

  14. Role of endothelial cells in bovine mammary gland health and disease.

    PubMed

    Ryman, Valerie E; Packiriswamy, Nandakumar; Sordillo, Lorraine M

    2015-12-01

    The bovine mammary gland is a dynamic and complex organ composed of various cell types that work together for the purpose of milk synthesis and secretion. A layer of endothelial cells establishes the blood-milk barrier, which exists to facilitate the exchange of solutes and macromolecules necessary for optimal milk production. During bacterial challenge, however, endothelial cells divert some of their lactation function to protect the underlying tissue from damage by initiating inflammation. At the onset of inflammation, endothelial cells tightly regulate the movement of plasma components and leukocytes into affected tissue. Unfortunately, endothelial dysfunction as a result of exacerbated or sustained inflammation can negatively affect both barrier integrity and the health of surrounding extravascular tissue. The objective of this review is to highlight the role of endothelial cells in supporting milk production and regulating optimal inflammatory responses. The consequences of endothelial dysfunction and sustained inflammation on milk synthesis and secretion are discussed. Given the important role of endothelial cells in orchestrating the inflammatory response, a better understanding of endothelial function during mastitis may support development of targeted therapies to protect bovine mammary tissue and mammary endothelium.

  15. Identification of a stable molecular signature in mammary tumor endothelial cells that persists in vitro

    PubMed Central

    Xiao, Lin; Harrell, J. Chuck; Perou, Charles M.; Dudley, Andrew C.

    2013-01-01

    Long-term, in vitro propagation of tumor-specific endothelial cells (TEC) allows for functional studies and genome-wide expression profiling of clonally-derived, well-characterized subpopulations. Using a genetically engineered mouse model (GEMM) of mammary adenocarcinoma, we have optimized an isolation procedure and defined growth conditions for long-term propagation of mammary TEC. The isolated TEC maintain their endothelial specification and phenotype in culture. Furthermore, gene expression profiling of multiple TEC subpopulations revealed striking, persistent overexpression of several candidate genes including Irx2 and Zfp503 (transcription factors), Alcam and Cd133 (cell surface markers), Ccl4 and neurotensin (Nts) (angiocrine factors), and Gpr182 and Cnr2 (G protein-coupled receptors, GPCRs). Taken together, we have developed an effective method for isolating and culture-expanding mammary TEC, and uncovered several new TEC-selective genes whose overexpression persists even after long-term in vitro culture. These results suggest that the tumor microenvironment may induce changes in vascular endothelium in vivo that are stably transmittable in vitro. PMID:24257808

  16. Molecular carcinogenesis of canine mammary tumors: news from an old disease.

    PubMed

    Klopfleisch, R; von Euler, H; Sarli, G; Pinho, S S; Gärtner, F; Gruber, A D

    2011-01-01

    Studies focusing on the molecular basis of canine mammary tumors (CMT) have long been hampered by limited numbers of molecular tools specific to the canine species. The lack of molecular information for CMT has impeded the identification of clinically relevant tumor markers beyond histopathology and the introduction of new therapeutic concepts. Additionally, the potential use for the dog as a model for human breast cancer is debatable until questions are answered regarding cellular origin, mechanisms, and cellular pathways. During the past years, increasing numbers of canine molecular tools have been developed on the genomic, RNA, and protein levels, and an increasing number of studies have shed light on specific aspects of canine carcinogenesis, particularly of the mammary gland. This review summarizes current knowledge on the molecular carcinogenesis of CMT, including the role of specific oncogenes, tumor suppressors, regulators of apoptosis and DNA repair, proliferation indices, adhesion molecules, circulating tumor cells, and mediators of angiogenesis in CMT progression and clinical behavior. Whereas the data available are far from complete, knowledge of molecular pathways has a significant potential to complement and refine the current diagnostic and therapeutic approach to this tumor type. Furthermore, current data show that significant similarities and differences exist between canine and human mammary tumors at the molecular level. Clearly, this is only the beginning of an understanding of the molecular mechanisms of CMT and their application in clinical patient management. PMID:21149845

  17. Laminin and biomimetic extracellular elasticity enhance functional differentiation in mammary epithelia

    PubMed Central

    Alcaraz, Jordi; Xu, Ren; Mori, Hidetoshi; Nelson, Celeste M; Mroue, Rana; Spencer, Virginia A; Brownfield, Doug; Radisky, Derek C; Bustamante, Carlos; Bissell, Mina J

    2008-01-01

    In the mammary gland, epithelial cells are embedded in a ‘soft' environment and become functionally differentiated in culture when exposed to a laminin-rich extracellular matrix gel. Here, we define the processes by which mammary epithelial cells integrate biochemical and mechanical extracellular cues to maintain their differentiated phenotype. We used single cells cultured on top of gels in conditions permissive for β-casein expression using atomic force microscopy to measure the elasticity of the cells and their underlying substrata. We found that maintenance of β-casein expression required both laminin signalling and a ‘soft' extracellular matrix, as is the case in normal tissues in vivo, and biomimetic intracellular elasticity, as is the case in primary mammary epithelial organoids. Conversely, two hallmarks of breast cancer development, stiffening of the extracellular matrix and loss of laminin signalling, led to the loss of β-casein expression and non-biomimetic intracellular elasticity. Our data indicate that tissue-specific gene expression is controlled by both the tissues' unique biochemical milieu and mechanical properties, processes involved in maintenance of tissue integrity and protection against tumorigenesis. PMID:18843297

  18. Biomechanical Approaches for Studying Integration of Tissue Structure and Function in Mammary Epithelia

    PubMed Central

    Alcaraz, Jordi; Nelson, Celeste M.; Bissell, Mina J.

    2010-01-01

    The structure and function of each individual mammary epithelial cell (MEC) is largely controlled by a bidirectional interchange of chemical and mechanical signals with the microenvironment. Most of these signals are tissue-specific, since they arise from the three-dimensional (3D) tissue organization and are modulated during mammary gland development, maturation, pregnancy, lactation, and involution. Although the important role played by structural and mechanical signals in mammary cell and tissue function is being increasingly recognized, quantitative biomechanical approaches are still scarce. Here we review currently available biomechanical tools that allow quantitative examination of individual cells, groups of cells or full monolayers in two-dimensional cultures, and cells in 3D cultures. Current technological limitations and challenges are discussed, with special emphasis on their potential applications in MEC biology. We argue that the combination of biomechanical tools with current efforts in mathematical modeling and in cell and molecular biology applied to 3D cultures provides a powerful approach to unravel the complexity of tissue-specific structure-function relationships. PMID:15838605

  19. Biomechanical approaches for studying integration of tissue structure and function in mammary epithelia.

    PubMed

    Alcaraz, Jordi; Nelson, Celeste M; Bissell, Mina J

    2004-10-01

    The structure and function of each individual mammary epithelial cell (MEC) is largely controlled by a bidirectional interchange of chemical and mechanical signals with the microenvironment. Most of these signals are tissue-specific, since they arise from the three-dimensional (3D) tissue organization and are modulated during mammary gland development, maturation, pregnancy, lactation, and involution. Although the important role played by structural and mechanical signals in mammary cell and tissue function is being increasingly recognized, quantitative biomechanical approaches are still scarce. Here we review currently available biomechanical tools that allow quantitative examination of individual cells, groups of cells or full monolayers in two-dimensional cultures, and cells in 3D cultures. Current technological limitations and challenges are discussed, with special emphasis on their potential applications in MEC biology. We argue that the combination of biomechanical tools with current efforts in mathematical modeling and in cell and molecular biology applied to 3D cultures provides a powerful approach to unravel the complexity of tissue-specific structure-function relationships.

  20. The severity of mammary gland developmental defects is linked to the overall functional status of Cx43 as revealed by genetically modified mice

    PubMed Central

    Stewart, Michael K. G.; Gong, Xiang-Qun; Barr, Kevin J.; Bai, Donglin; Fishman, Glenn I.; Laird, Dale W.

    2012-01-01

    Genetically modified mice mimicking ODDD (oculodentodigital dysplasia), a disease characterized by reduced Cx43 (connexin 43)-mediated gap junctional intercellular communication, represent an in vivo model to assess the role of Cx43 in mammary gland development and function. We previously reported that severely compromised Cx43 function delayed mammary gland development and impaired milk ejection in mice that harboured a G60S Cx43 mutant, yet there are no reports of lactation defects in ODDD patients. To address this further, we obtained a second mouse model of ODDD expressing an I130T Cx43 mutant to assess whether a mutant with partial gap junction channel activity would be sufficient to retain mammary gland development and function. The results of the present study show that virgin Cx43I130T/+ mice exhibited a temporary delay in ductal elongation at 4 weeks. In addition, Cx43I130T/+ mice develop smaller mammary glands at parturition due to reduced cell proliferation despite similar overall gland architecture. Distinct from Cx43G60S/+ mice, Cx43I130T/+ mice adequately produce and deliver milk to pups, suggesting that milk ejection is unaffected. Thus the present study suggests that a loss-of-function mutant of Cx43 with partial gap junction channel coupling conductance results in a less severe mammary gland phenotype, which may partially explain the lack of reported lactation defects associated with ODDD patients. PMID:23075222

  1. Mammary sensitivity to protein restriction and re-alimentation.

    PubMed

    Goodwill, M G; Jessop, N S; Oldham, J D

    1996-09-01

    The present study tested the influence of protein undernutrition and re-alimentation on mammary gland size and secretory cell activity in lactating rats. During gestation, female Sprague-Dawley rats were offered a high-protein diet (215 g crude protein (N x 6.25; CP)/kg DM; H); litters were standardized to twelve pups at parturition. During lactation, two diets were offered ad libitum, diet H and a low-protein diet (90 g CP/kg DM; L). Lactational dietary treatments were the supply ad libitum of either diet H (HHH) or diet L (LLL) for the first 12 d of lactation, or diet L transferring to diet H on either day 6 (LHH) or 9 (LLH) of lactation. On days 1, 6, 9 and 12 of lactation, rats from each group (n > or = 6) were used to estimate mammary dry mass, fat, protein, DNA and RNA; the activities of lactose synthetase (EC 2.4.1.22) enzyme and Na+,K(+)-ATPase (EC 3.6.1.37) were also measured. Rats offered a diet considered protein sufficient (H) from day 1 of lactation showed a decrease in mammary dry mass and fat but an increase in DNA, RNA and protein on day 6, after which there was no further change, except for mammary protein which continued to increase. However, rats offered diet L showed a steady loss in mammary mass and fat throughout the 12 d lactation period and no change in mammary DNA, RNA or protein. Rats previously protein restricted for either the first 6 or 9 d of lactation had their mammary dry mass and mammary fat loss halted and showed a rapid increase in mammary DNA, RNA and protein on re-alimentation. Lactose production in group HHH, as measured by lactose synthetase activity, was similar on days 1 and 6 of lactation, after which a significant increase was seen. Protein-restricted rats showed no change in lactose synthetase activity during the 12 d experimental period. Changing from diet L to diet H led to a significant increase in lactose synthetase activity to levels comparable with those offered diet H from day 1. These results show that rats

  2. Multiplex Gene Expression Profiling of 16 Target Genes in Neoplastic and Non-Neoplastic Canine Mammary Tissues Using Branched-DNA Assay

    PubMed Central

    Lüder Ripoli, Florenza; Conradine Hammer, Susanne; Mohr, Annika; Willenbrock, Saskia; Hewicker-Trautwein, Marion; Brenig, Bertram; Murua Escobar, Hugo; Nolte, Ingo

    2016-01-01

    Mammary gland tumors are one of the most common neoplasms in female dogs, and certain breeds are prone to develop the disease. The use of biomarkers in canines is still restricted to research purposes. Therefore, the necessity to analyze gene profiles in different mammary entities in large sample sets is evident in order to evaluate the strength of potential markers serving as future prognostic factors. The aim of the present study was to analyze the gene expression of 16 target genes (BRCA1, BRCA2, FOXO3, GATA4, HER2, HMGA1, HMGA2, HMGB1, MAPK1, MAPK3, MCL1, MYC, PFDN5, PIK3CA, PTEN, and TP53) known to be involved in human and canine mammary neoplasm development. Expression was analyzed in 111 fresh frozen (FF) and in 170 formalin-fixed, paraffin-embedded (FFPE) specimens of neoplastic and non-neoplastic canine mammary tissues using a multiplexed branched-DNA (b-DNA) assay. TP53, FOXO3, PTEN, and PFDN5 expression revealed consistent results with significant low expression in malignant tumors. The possibility of utilizing them as predictive factors as well as for assisting in the choice of an adequate gene therapy may help in the development of new and improved approaches in canine mammary tumors. PMID:27657059

  3. Expression of constitutively activated Akt in the mammary gland leads to excess lipid synthesis during pregnancy and lactation.

    PubMed

    Schwertfeger, Kathryn L; McManaman, James L; Palmer, Carol A; Neville, Margaret C; Anderson, Steven M

    2003-06-01

    Expression of constitutively activated Akt in the mammary glands of transgenic mice results in a delay in post-lactational involution. We now report precocious lipid accumulation in the alveolar epithelium of mouse mammary tumor virus-myr-Akt transgenic mice accompanied by a lactation defect that results in a 50% decrease in litter weight over the first 9 days of lactation. Although ductal structures and alveolar units develop normally during pregnancy, cytoplasmic lipid droplets appeared precociously in mammary epithelial cells in early pregnancy and were accompanied by increased expression of adipophilin, which is associated with lipid droplets. By late pregnancy the lipid droplets had become significantly larger than in nontransgenic mice, and they persisted into lactation. The fat content of milk from lactating myr-Akt transgenic mice was 65-70% by volume compared to 25-30% in wild-type mice. The diminished growth of pups nursed by transgenic mothers could result from the high viscosity of the milk and the inability of the pups to remove sufficient quantities of milk by suckling. Transduction of the CIT3 mammary epithelial cell line with a recombinant human adenovirus encoding myr-Akt resulted in an increase in glucose transport and lipid biosynthesis, suggesting that Akt plays an important role in regulation of lipid metabolism. PMID:12700340

  4. PTK6/BRK is expressed in the normal mammary gland and activated at the plasma membrane in breast tumors.

    PubMed

    Peng, Maoyu; Emmadi, Rajyasree; Wang, Zebin; Wiley, Elizabeth L; Gann, Peter H; Khan, Seema A; Banerji, Nilanjana; McDonald, William; Asztalos, Szilard; Pham, Thao N D; Tonetti, Debra A; Tyner, Angela L

    2014-08-15

    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-10A human mammary gland epithelial cell line, and examined PTK6 expression and activation in a normal human breast tissue microarray, as well as in human breast tumors. Phosphorylation of tyrosine residue 342 in the PTK6 activation loop corresponds with its activation. Similar to findings in the prostate, we detect nuclear and cytoplasmic PTK6 in normal mammary gland epithelial cells, but no phosphorylation of tyrosine residue 342. However, in human breast tumors, striking PTK6 expression and phosphorylation of tyrosine 342 is observed at the plasma membrane. PTK6 is expressed in the normal human mammary gland, but does not appear to be active and may have kinase-independent functions that are distinct from its cancer promoting activities at the membrane. Understanding consequences of PTK6 activation at the plasma membrane may have implications for developing novel targeted therapies against this kinase.

  5. Changes in PACAP immunoreactivity in human milk and presence of PAC1 receptor in mammary gland during lactation.

    PubMed

    Csanaky, Katalin; Banki, Eszter; Szabadfi, Krisztina; Reglodi, Dora; Tarcai, Ibolya; Czegledi, Levente; Helyes, Zsuzsanna; Ertl, Tibor; Gyarmati, Judit; Szanto, Zalan; Zapf, Istvan; Sipos, Erika; Shioda, Seiji; Tamas, Andrea

    2012-11-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide with widespread occurrence in the nervous system and peripheral organs, including the mammary gland. Previously, we have shown that PACAP38 is present in the human milk at higher levels than in respective blood samples. However, it is not known how PACAP levels and the expression of PAC1 receptor change during lactation. Therefore, the aim of our study was to investigate PACAP38-like immunoreactivity (PACAP38-LI) in human colostrums and transitional and mature milk during lactation and to compare the expression of PAC1 receptors in lactating and non-lactating mammary glands. We found that PACAP38-LI was significantly higher in human colostrum samples than in the transitional and mature milk. PACAP38-LI did not show any significant changes within the first 10-month period of lactation, but a significant increase was observed thereafter, up to the examined 17th month. Weak expression of PAC1 receptors was detected in non-lactating sheep and human mammary glands, but a significant increase was observed in the lactating sheep samples. In summary, the present study is the first to show changes of PACAP levels in human milk during lactation. The presence of PACAP in the milk suggests a potential role in the development of newborn, while the increased expressions of PAC1 receptors on lactating breast may indicate a PACAP38/PAC1 interaction in the mammary gland during lactation.

  6. The plasticizer butyl benzyl phthalate induces genomic changes in rat mammary gland after neonatal/prepubertal exposure

    PubMed Central

    Moral, Raquel; Wang, Richard; Russo, Irma H; Mailo, Daniel A; Lamartiniere, Coral A; Russo, Jose

    2007-01-01

    Background Phthalate esters like n-butyl benzyl phthalate (BBP) are widely used plasticizers. BBP has shown endocrine-disrupting properties, thus having a potential effect on hormone-sensitive tissues. The aim of this study is to determine the effect of neonatal/prepubertal exposure (post-natal days 2–20) to BBP on maturation parameters and on the morphology, proliferative index and genomic signature of the rat mammary gland at different ages of development (21, 35, 50 and 100 days). Results Here we show that exposure to BBP increased the uterine weight/body weight ratio at 21 days and decreased the body weight at time of vaginal opening. BBP did not induce significant changes on the morphology of the mammary gland, but increased proliferative index in terminal end buds at 35 days and in lobules 1 at several ages. Moreover, BBP had an effect on the genomic profile of the mammary gland mainly at the end of the exposure (21 days), becoming less prominent thereafter. By this age a significant number of genes related to proliferation and differentiation, communication and signal transduction were up-regulated in the glands of the exposed animals. Conclusion These results suggest that BBP has an effect in the gene expression profile of the mammary gland. PMID:18062813

  7. Social isolation induces autophagy in the mouse mammary gland: link to increased mammary cancer risk.

    PubMed

    Sumis, Allison; Cook, Katherine L; Andrade, Fabia O; Hu, Rong; Kidney, Emma; Zhang, Xiyuan; Kim, Dominic; Carney, Elissa; Nguyen, Nguyen; Yu, Wei; Bouker, Kerrie B; Cruz, Idalia; Clarke, Robert; Hilakivi-Clarke, Leena

    2016-10-01

    Social isolation is a strong predictor of early all-cause mortality and consistently increases breast cancer risk in both women and animal models. Because social isolation increases body weight, we compared its effects to those caused by a consumption of obesity-inducing diet (OID) in C57BL/6 mice. Social isolation and OID impaired insulin and glucose sensitivity. In socially isolated, OID-fed mice (I-OID), insulin resistance was linked to reduced Pparg expression and increased neuropeptide Y levels, but in group-housed OID fed mice (G-OID), it was linked to increased leptin and reduced adiponectin levels, indicating that the pathways leading to insulin resistance are different. Carcinogen-induced mammary tumorigenesis was significantly higher in I-OID mice than in the other groups, but cancer risk was also increased in socially isolated, control diet-fed mice (I-C) and G-OID mice compared with that in controls. Unfolded protein response (UPR) signaling (GRP78; IRE1) was upregulated in the mammary glands of OID-fed mice, but not in control diet-fed, socially isolated I-C mice. In contrast, expression of BECLIN1, ATG7 and LC3II were increased, and p62 was downregulated by social isolation, indicating increased autophagy. In the mammary glands of socially isolated mice, but not in G-OID mice, mRNA expressions of p53 and the p53-regulated autophagy inducer Dram1 were upregulated, and nuclear p53 staining was strong. Our findings further indicated that autophagy and tumorigenesis were not increased in Atg7(+/-) mice kept in social isolation and fed OID. Thus, social isolation may increase breast cancer risk by inducing autophagy, independent of changes in body weight. PMID:27550962

  8. Social isolation induces autophagy in the mouse mammary gland: link to increased mammary cancer risk.

    PubMed

    Sumis, Allison; Cook, Katherine L; Andrade, Fabia O; Hu, Rong; Kidney, Emma; Zhang, Xiyuan; Kim, Dominic; Carney, Elissa; Nguyen, Nguyen; Yu, Wei; Bouker, Kerrie B; Cruz, Idalia; Clarke, Robert; Hilakivi-Clarke, Leena

    2016-10-01

    Social isolation is a strong predictor of early all-cause mortality and consistently increases breast cancer risk in both women and animal models. Because social isolation increases body weight, we compared its effects to those caused by a consumption of obesity-inducing diet (OID) in C57BL/6 mice. Social isolation and OID impaired insulin and glucose sensitivity. In socially isolated, OID-fed mice (I-OID), insulin resistance was linked to reduced Pparg expression and increased neuropeptide Y levels, but in group-housed OID fed mice (G-OID), it was linked to increased leptin and reduced adiponectin levels, indicating that the pathways leading to insulin resistance are different. Carcinogen-induced mammary tumorigenesis was significantly higher in I-OID mice than in the other groups, but cancer risk was also increased in socially isolated, control diet-fed mice (I-C) and G-OID mice compared with that in controls. Unfolded protein response (UPR) signaling (GRP78; IRE1) was upregulated in the mammary glands of OID-fed mice, but not in control diet-fed, socially isolated I-C mice. In contrast, expression of BECLIN1, ATG7 and LC3II were increased, and p62 was downregulated by social isolation, indicating increased autophagy. In the mammary glands of socially isolated mice, but not in G-OID mice, mRNA expressions of p53 and the p53-regulated autophagy inducer Dram1 were upregulated, and nuclear p53 staining was strong. Our findings further indicated that autophagy and tumorigenesis were not increased in Atg7(+/-) mice kept in social isolation and fed OID. Thus, social isolation may increase breast cancer risk by inducing autophagy, independent of changes in body weight.

  9. Enhancement of NAD+-dependent SIRT1 deacetylase activity by methylselenocysteine resets the circadian clock in carcinogen-treated mammary epithelial cells

    PubMed Central

    Fang, Mingzhu; Guo, Wei-Ren; Park, Youngil; Kang, Hwan-Goo; Zarbl, Helmut

    2015-01-01

    We previously reported that dietary methylselenocysteine (MSC) inhibits N-methyl-N-nitrosourea (NMU)-induced mammary tumorigenesis by resetting circadian gene expression disrupted by the carcinogen at the early stage of tumorigenesis. To investigate the underlying mechanism, we developed a circadian reporter system comprised of human mammary epithelial cells with a luciferase reporter driven by the promoter of human PERIOD 2 (PER2), a core circadian gene. In this in vitro model, NMU disrupted cellular circadian rhythm in a pattern similar to that observed with SIRT1-specific inhibitors; in contrast, MSC restored the circadian rhythms disrupted by NMU and protected against SIRT1 inhibitors. Moreover, NMU inhibited intracellular NAD+/NADH ratio and reduced NAD+-dependent SIRT1 activity in a dose-dependent manner, while MSC restored NAD+/NADH and SIRT1 activity in the NMU-treated cells, indicating that the NAD+-SIRT1 pathway was targeted by NMU and MSC. In rat mammary tissue, a carcinogenic dose of NMU also disrupted NAD+/NADH oscillations and decreased SIRT1 activity; dietary MSC restored NAD+/NADH oscillations and increased SIRT1 activity in the mammary glands of NMU-treated rats. MSC-induced SIRT1 activity was correlated with decreased acetylation of BMAL1 and increased acetylation of histone 3 lysine 9 at the Per2 promoter E-Box in mammary tissue. Changes in SIRT1 activity were temporally correlated with loss or restoration of rhythmic Per2 mRNA expression in NMU-treated or MSC-rescued rat mammary glands, respectively. Together with our previous findings, these results suggest that enhancement of NAD+-dependent SIRT1 activity contributes to the chemopreventive efficacy of MSC by restoring epigenetic regulation of circadian gene expression at early stages of mammary tumorigenesis. PMID:26544624

  10. Prepubertal exposure to zearalenone or genistein reduces mammary tumorigenesis.

    PubMed

    Hilakivi-Clarke, L; Onojafe, I; Raygada, M; Cho, E; Skaar, T; Russo, I; Clarke, R

    1999-08-01

    Prepubertal exposure to a pharmacological dose (500 mg kg(-1)) of the phyto-oestrogen genistein can reduce the incidence and multiplicity of carcinogen-induced mammary tumours in rats. However, such an exposure also disrupts the function of the hypothalamic-pituitary-gonadal axis, making it unsuitable for breast cancer prevention. We studied whether prepubertal exposure to genistein at a total body dose broadly comparable to the level typical of Oriental countries, approximately 1 mg kg(-1) body weight, affects mammary tumorigenesis. We also studied whether prepubertal exposure to zearalenone, a major source for phyto-oestrogens in the USA, influences breast cancer risk. Prepubertal rats were treated between postnatal days 7 and 20, with 20 microg (approximately 1 mg kg(-1) body weight) of either genistein or zearalenone. Zearalenone exposure significantly reduced both the incidence and multiplicity of mammary tumours induced by 7,12-dimethylbenz(a)anthracene (DMBA). Genistein exposure significantly reduced tumour multiplicity, but not tumour incidence, when compared with vehicle-treated animals. Furthermore, 60% of the tumours in the genistein group were not malignant, while all the tumours analysed for histopathology in the vehicle and zearalenone groups were adenocarcinomas. A higher number of differentiated alveolar buds, and lower number of terminal ducts, were present in the DMBA-treated mammary glands of the phyto-oestrogen exposed rats. The concentration of oestrogen receptor (ER) binding sites after the DMBA treatment was low in the mammary glands of all groups but a significantly higher proportion of the glands in the zearalenone exposed rats were ER-positive (i.e. ER levels > or = 5 fmol mg(-1) protein) than the glands of the vehicle controls. Our data suggest that a prepubertal exposure to a low dose of either zearalenone or genistein may protect the mammary gland from carcinogen-induced malignant transformation, possibly by increasing differentiation

  11. TGF-β1 promotes bovine mammary fibroblast proliferation through the ERK 1/2 signalling pathway.

    PubMed

    Gao, Yuanyuan; Wang, Yuping; Li, Yingying; Xia, Xiaojing; Zhao, Shuang; Che, Yanyi; Sun, Yingying; Lei, Liancheng

    2016-07-01

    The abnormal proliferation of bovine mammary fibroblasts (BMFBs) impairs mammary gland development and lactation. Severe manifestations develop into breast fibrosis, leading to the culling of cows and causing serious losses to the dairy industry. Transforming growth factor β1 (TGF-β1) is an important modulator of cell proliferation and extracellular matrix formation; however, limited information is available on BMFBs. In this study, a convenient and stable culture method for BMFBs was established. Treatment with 5 ng/mL of TGF-β1 significantly promoted the proliferation of BMFBs and accelerated the cell cycle. TGF-β1 stimulation for up to 12 h significantly increased the relative ERK1/2 mRNA expression and enhanced the protein expression of p-ERK1/2 and cyclin D1. Conversely, the ERK1/2 inhibitor PD98059 blocked these TGF-β1 effects. Further exploration using a mouse model showed that TGF-β1 significantly increased the proportion of fibroblasts and accelerating the cell transition from the G1 to G2/M phases. In addition, TGF-β1 enhanced the expression of fibrosis markers, α-SMA and I Collagen, which could be blocked efficiently by the PD98059 in mouse mammary gland. Finally, immunofluorescence analysis confirmed that TGF-β1 promoted fibroblast proliferation in healthy dairy cows after normal long-term dietary corn straw roughage supplementation. It is suggested that the diet may promote mammary fibroblast proliferation by raising the level of TGF-β1. Our study provides new insights into how nutrition causes undesirable changes in mammary gland structure.

  12. Repression of cathepsin E expression increases the risk of mammary carcinogenesis and links to poor prognosis in breast cancer.

    PubMed

    Kawakubo, Tomoyo; Yasukochi, Atsushi; Toyama, Tatsuya; Takahashi, Satoru; Okamoto, Kuniaki; Tsukuba, Takayuki; Nakamura, Seiji; Ozaki, Yasuhiko; Nishigaki, Koichi; Yamashita, Hiroko; Yamamoto, Kenji

    2014-03-01

    Despite advances in detection and treatment for breast cancer (BC), recurrence and death rates remain unacceptably high. Therefore, more convenient diagnostic and prognostic methods still required to optimize treatments among the patients. Here, we report the clinical significance of the serum cathepsin E (CatE) activity as a novel prognostic marker for BC. Correlation analysis between the serum levels of CatE expression and clinicopathological parameters revealed that the activity levels, but not the protein levels, were negatively associated with the stages and progression of BC. Univariate and multivariate analyses demonstrated that the serum CatE activity was significantly correlated with favorable prognostic outcomes of the patients. The functional link of CatE expression to BC progression was further corroborated by in vivo and in vitro studies with mice exhibiting different levels of CatE expression. Multiparous CatE (-) (/) (-) mice spontaneously developed mammary tumors concomitant with morphological transformation and altered growth characteristics of the mammary glands. These alterations were associated in part with the induction of epithelial-mesenchymal transition and the activation of β-catenin-dependent pathway in mammary cells. Loss of CatE strongly induced the translocation and accumulation of Wnt5a in the nuclei, thereby leading to the aberrant trafficking, maturation and secretion of Wnt5a and the impaired signaling. The interaction of CatE and Wnt5a was verified by proximity ligation assay and by knockdown or restoration of CatE expression in the mammary cells. Consequently, our data demonstrate that CatE contributes to normal growth and development of mammary glands through proper trafficking and secretion of Wnt5a.

  13. Mammary analogue secretory carcinoma mimicking salivary adenoma.

    PubMed

    Williams, Lindsay; Chiosea, Simion I

    2013-12-01

    Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor characterized by ETV6 translocation. It appears that prior studies have identified MASC by reviewing salivary gland carcinomas, such as acinic cell carcinoma and adenocarcinoma, not otherwise specified. To address the possibility of MASC mimicking benign salivary neoplasms we reviewed 12 salivary gland (cyst)adenomas diagnosed prior to the discovery of MASC. One encapsulated (cyst)adenoma of the parotid gland demonstrated features of MASC. The diagnosis was confirmed by fluorescence in situ hybridization with an ETV6 break-apart probe. An unusual complex pattern of ETV6 rearrangement with duplication of the telomeric/distal ETV6 probe was identified. This case illustrates that MASC may mimic salivary (cyst)adenomas. To more accurately assess true clinical and morphologic spectrum of MASC, future studies may have to include review of salivary (cyst)adenomas. The differential diagnosis of MASC may have to be expanded to include cases resembling salivary (cyst)adenomas.

  14. Pseudoangiomatous hyperplasia of mammary stroma associated with gynaecomastia.

    PubMed Central

    Milanezi, M F; Saggioro, F P; Zanati, S G; Bazan, R; Schmitt, F C

    1998-01-01

    AIMS: To evaluate the prevalence of pseudoangiomatous hyperplasia of mammary stroma in gynaecomastia and its immunohistochemical profile in this setting. METHODS: Eighty eight cases of gynaecomastia recovered from the files of the department of pathology, Botucatu School of Medicine from 1976 to 1996 were studied. In the cases associated with pseudoangiomatous hyperplasia of mammary stroma, immunoreactivity for cytokeratins (CAM 5.2), vimentin, CD34, factor VIII related antigen, and the oestrogen and progesterone receptors were studied. RESULTS: Pseudoangiomatous hyperplasia of mammary stroma was found in 21 of 88 cases of gynaecomastia (23.8%). In all cases, the cells lining the spaces were positive for vimentin, whereas CAM 5.2 and factor VIII related antigen were consistently negative. Nineteen of the 21 cases showed immunoreactivity for CD34. Ductal epithelial cells were positive for both the oestrogen receptor and the progesterone receptor, whereas stromal cells were negative. CONCLUSIONS: Pseudoangiomatous hyperplasia of mammary stroma was present in approximately one quarter of the cases of gynaecomastia. This immunohistochemical study confirms the mesenchymal origin of the stromal cells that line the pseudovascular spaces, as has been found in female cases of pseudoangiomatous hyperplasia of mammary stroma. Images PMID:9659260

  15. A model of spontaneous mouse mammary tumor for human estrogen receptor- and progesterone receptor-negative breast cancer

    PubMed Central

    ZHENG, LIXIANG; ZHOU, BUGAO; MENG, XIANMING; ZHU, WEIFENG; ZUO, AIREN; WANG, XIAOMIN; JIANG, RUNDE; YU, SHIPING

    2014-01-01

    Breast cancer (BC) is the most frequently malignancy in women. Therefore, establishment of an animal model for the development of preventative measures and effective treatment for tumors is required. A novel heterogeneous spontaneous mammary tumor animal model of Kunming mice was generated. The purpose of this study was to characterize the spontaneous mammary tumor model. Histopathologically, invasive nodular masses of pleomorphic tubular neoplastic epithelial cells invaded fibro-vascular stroma, adjacent dermis and muscle tissue. Metastatic spread through blood vessel into liver and lungs was observed by hematoxylin eosin staining. No estrogen receptor (ER) or progesterone receptor (PR) immunoreactivity was detected in their associated malignant tumors, human epidermal growth factor receptor-2 (HER-2) protein weak expression was found by immunohistochemistry. High expression of vascular endoth