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Developmental Cell Jul 2021Cell fate decisions are critical for adequate tissue development, maintenance and regeneration. In the mammary gland, epithelial cell fates are tightly controlled by the... (Review)
Review
Cell fate decisions are critical for adequate tissue development, maintenance and regeneration. In the mammary gland, epithelial cell fates are tightly controlled by the microenvironment. Here, we review how cell fate decisions are regulated by components of the microenvironment during mammary gland development and how pathological changes in the microenvironment can alter cell fates, leading to malignancy. Specifically, we describe the current understanding of how mammary cell fate is controlled and directed by three elements: the extracellular matrix, the immune microenvironment, and hormones-and how these elements can converge to create microenvironments that promote a fourth element: DNA damage.
Topics: Animals; Breast; Cell Differentiation; Cell Lineage; Cellular Microenvironment; Extracellular Matrix; Female; Humans; Mammary Glands, Animal; Mammary Glands, Human; Neoplasms; Tumor Microenvironment
PubMed: 34256927
DOI: 10.1016/j.devcel.2021.06.016 -
Seminars in Cell & Developmental Biology Jun 2021Emerging evidence has shown that several SOX family transcription factors are key regulators of stem/progenitor cell fates in the mammary gland. These cell-fate... (Review)
Review
Emerging evidence has shown that several SOX family transcription factors are key regulators of stem/progenitor cell fates in the mammary gland. These cell-fate regulators are often upregulated in breast cancer and contribute to tumor initiation and progression. They induce lineage plasticity and the epithelial-mesenchymal transition, which promotes tumor invasion, metastasis, and therapeutic resistance. SOX factors act through modulating multiple oncogenic signaling pathways in breast cancer. In addition to the cell-autonomous functions, new evidence suggests they can shape the tumor immune microenvironment. Here, we will review the molecular and functional evidence linking SOX factors with mammary gland development and discuss how these cell-fate regulators are co-opted in breast cancer.
Topics: Breast Neoplasms; Female; Humans; Mammary Glands, Human; SOX Transcription Factors
PubMed: 33583737
DOI: 10.1016/j.semcdb.2021.01.002 -
Genes Jan 2021The Cub Sushi Multiple Domains-1 (CSMD1) protein is a tumour suppressor which has been shown to play a role in regulating human mammary duct development in vitro....
The Cub Sushi Multiple Domains-1 (CSMD1) protein is a tumour suppressor which has been shown to play a role in regulating human mammary duct development in vitro. knockdown in vitro demonstrated increased cell proliferation, invasion and motility. However, the role of Csmd1 in vivo is poorly characterised when it comes to ductal development and is therefore an area which warrants further exploration. In this study a knockout (KO) mouse model was used to identify the role of Csmd1 in regulating mammary gland development during puberty. Changes in duct development and protein expression patterns were analysed by immunohistochemistry. This study identified increased ductal development during the early stages of puberty in the KO mice, characterised by increased ductal area and terminal end bud number at 6 weeks. Furthermore, increased expression of various proteins (Stat1, Fak, Akt, Slug/Snail and Progesterone receptor) was shown at 4 weeks in the KO mice, followed by lower expression levels from 6 weeks in the KO mice compared to the wild type mice. This study identifies a novel role for Csmd1 in mammary gland development, with Csmd1 KO causing significantly more rapid mammary gland development, suggesting an earlier adult mammary gland formation.
Topics: Animals; Female; Gene Expression Regulation; Immunohistochemistry; Mammary Glands, Animal; Membrane Proteins; Mice; Mice, Knockout; Organogenesis; Sexual Maturation; Tumor Suppressor Proteins
PubMed: 33530646
DOI: 10.3390/genes12020162 -
Cancers Sep 2019Fluidity in cell fate or heterogeneity in cell identity is an interesting cell biological phenomenon, which at the same time poses a significant obstacle for cancer... (Review)
Review
Fluidity in cell fate or heterogeneity in cell identity is an interesting cell biological phenomenon, which at the same time poses a significant obstacle for cancer therapy. The mammary gland seems a relatively straightforward organ with stromal cells and basal- and luminal- epithelial cell types. In reality, the epithelial cell fates are much more complex and heterogeneous, which is the topic of this review. Part of the complexity comes from the dynamic nature of this organ: the primitive epithelial tree undergoes extensively remodeling and expansion during puberty, pregnancy, and lactation and, unlike most other organs, the bulk of mammary gland development occurs late, during puberty. An active cell biological debate has focused on lineage commitment to basal- and luminal- epithelial cell fates by epithelial progenitor and stem cells; processes that are also relevant to cancer biology. In this review, we discuss the current understanding of heterogeneity in mammary gland and recent insights obtained through lineage tracing, signaling assays, and organoid cultures. Lastly, we relate these insights to cancer and ongoing efforts to resolve heterogeneity in breast cancer with single-cell RNAseq approaches.
PubMed: 31554261
DOI: 10.3390/cancers11101423 -
Journal of Dairy Science Oct 2021Infections of the mammary gland remain a frequent disease of dairy ruminants that negatively affect animal welfare, milk quality, farmer serenity, and farming... (Review)
Review
Infections of the mammary gland remain a frequent disease of dairy ruminants that negatively affect animal welfare, milk quality, farmer serenity, and farming profitability and cause an increase in use of antimicrobials. There is a need for efficacious vaccines to alleviate the burden of mastitis in dairy farming, but this need has not been satisfactorily fulfilled despite decades of research. A careful appraisal of past and current research on mastitis vaccines reveals the peculiarities but also the commonalities among mammary gland infections associated with the major mastitis pathogens Escherichia coli, Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae, or Streptococcus dysgalactiae. A major pitfall is that the immune mechanisms of effective protection have not been fully identified. Until now, vaccine development has been directed toward the generation of antibodies. In this review, we drew up an inventory of the main approaches used to design vaccines that aim at the major pathogens for the mammary gland, and we critically appraised the current and tentative vaccines. In particular, we sought to relate efficacy to vaccine-induced defense mechanisms to shed light on some possible reasons for current vaccine shortcomings. Based on the lessons learned from past attempts and the recent results of current research, the design of effective vaccines may take a new turn in the years to come.
Topics: Animals; Cattle; Cattle Diseases; Female; Mammary Glands, Animal; Mastitis; Mastitis, Bovine; Streptococcal Infections; Streptococcus; Vaccines
PubMed: 34218921
DOI: 10.3168/jds.2021-20434 -
Journal of Mammary Gland Biology and... Jul 2023The adaptor proteins NCK1 and NCK2 are well-established signalling nodes that regulate diverse biological processes including cell proliferation and actin dynamics in...
The adaptor proteins NCK1 and NCK2 are well-established signalling nodes that regulate diverse biological processes including cell proliferation and actin dynamics in many tissue types. Here we have investigated the distribution and function of Nck1 and Nck2 in the developing mouse mammary gland. Using publicly available single-cell RNA sequencing data, we uncovered distinct expression profiles between the two paralogs. Nck1 showed widespread expression in luminal, basal, stromal and endothelial cells, while Nck2 was restricted to luminal and basal cells, with prominent enrichment in hormone-sensing luminal subtypes. Next, using mice with global knockout of Nck1 or Nck2, we assessed mammary gland development during and after puberty (5, 8 and 12 weeks of age). Mice lacking Nck1 or Nck2 displayed significant defects in ductal outgrowth and branching at 5 weeks compared to controls, and the defects persisted in Nck2 knockout mice at 8 weeks before normalizing at 12 weeks. These defects were accompanied by an increase in epithelial cell proliferation at 5 weeks and a decrease at 8 weeks in both Nck1 and Nck2 knockout mice. We also profiled expression of several key genes associated with mammary gland development at these timepoints and detected temporal changes in transcript levels of hormone receptors as well as effectors of cell proliferation and migration in Nck1 and Nck2 knockout mice, in line with the distinct phenotypes observed at 5 and 8 weeks. Together these studies reveal a requirement for NCK proteins in mammary gland morphogenesis, and suggest that deregulation of Nck expression could drive breast cancer progression and metastasis.
Topics: Animals; Mice; Mice, Knockout; Mice, Inbred C57BL; Mammary Glands, Animal; Adaptor Proteins, Signal Transducing; Cell Proliferation; Epithelial Cells; Gene Expression
PubMed: 37479911
DOI: 10.1007/s10911-023-09541-1 -
Cellular and Molecular Life Sciences :... Aug 202117β-estradiol controls post-natal mammary gland development and exerts its effects through Estrogen Receptor ERα, a member of the nuclear receptor family. ERα is also... (Review)
Review
17β-estradiol controls post-natal mammary gland development and exerts its effects through Estrogen Receptor ERα, a member of the nuclear receptor family. ERα is also critical for breast cancer progression and remains a central therapeutic target for hormone-dependent breast cancers. In this review, we summarize the current understanding of the complex ERα signaling pathways that involve either classical nuclear "genomic" or membrane "non-genomic" actions and regulate in concert with other hormones the different stages of mammary development. We describe the cellular and molecular features of the luminal cell lineage expressing ERα and provide an overview of the transgenic mouse models impacting ERα signaling, highlighting the pivotal role of ERα in mammary gland morphogenesis and function and its implication in the tumorigenic processes. Finally, we describe the main features of the ERα-positive luminal breast cancers and their modeling in mice.
Topics: Animals; Breast Neoplasms; Carcinogenesis; Estrogen Receptor alpha; Female; Humans; Mammary Glands, Animal; Mammary Glands, Human; Signal Transduction
PubMed: 34156490
DOI: 10.1007/s00018-021-03860-4 -
Frontiers in Physiology 2022Branching morphogenesis is the process that gives rise to branched structures in several organs, such as the lung, the kidney, and the mammary gland. Although...
Branching morphogenesis is the process that gives rise to branched structures in several organs, such as the lung, the kidney, and the mammary gland. Although morphologically well described, the exact mechanisms driving branch elongation and bifurcation are still poorly understood. Signaling cues from the stroma and extracellular matrix have an important role in driving branching morphogenesis. Organoid models derived from primary mammary epithelial cells have emerged as a powerful tool to gain insight into branching morphogenesis of the mammary gland. However, current available mammary organoid culture protocols result in morphologically simple structures which do not resemble the complex branched structure of the mammary gland. Supplementation of growth factors to mammary organoids cultured in basement membrane extract or collagen I were shown to induce bud formation and elongation but are not sufficient to drive true branching events. Here, we present an improved culture approach based on 3D primary mammary epithelial cell culture to develop branched organoids with a complex morphology. By alternating the addition of fibroblast growth factor 2 and epidermal growth factor to mammary organoids cultured in a basement membrane extract matrix enriched with collagen type I fibers, we obtain complex mammary organoid structures with primary, secondary, and tertiary branches over a period of 15-20 days. Mammary organoid structures grow >1 mm in size and show an elongated and branched shape which resembles mammary gland morphology. This novel branched mammary organoid model offers many possibilities to study the mechanisms of branching in the developing mammary gland.
PubMed: 35399282
DOI: 10.3389/fphys.2022.826107 -
European Journal of Cell Biology 2021Breast cancer is primarily derived from mammary epithelial cells, the main cell type in human mammary glands. The majority of knowledge gained thus far around breast...
Breast cancer is primarily derived from mammary epithelial cells, the main cell type in human mammary glands. The majority of knowledge gained thus far around breast cancer has come from research using immortalized epithelial cell lines. The use of primary cells derived from breast tissue can be used in research to provide more biological relevance representative of the heterogeneous nature of breast cancer development and metastasis in its natural microenvironment. However, the successful isolation and propagation of human primary mammary gland cells can be costly and difficult due to their complex in vivo microenvironment and sensitivity when isolated. Here, we present a gentle isolation method for viable human mammary epithelial cells (hMECs) and donor-matched human mammary fibroblasts (hMFbs) from human mammary gland tissue. We isolated, expanded and passaged the hMECs and hMFbs in vitro and characterized cultures using cell-specific markers. A total of four primary cell lines were isolated and established from normal breast tissue and characterized through various markers, including pan cytokeratin (panCK), CK14, CD44, CD31, fibronectin and vimentin by immunofluorescence. To determine functional potential for subsequent studies, epithelial cells were examined via Matrigel® assays to assess spheroid development. Both cell type cultures expressed lineage specific markers with hMECs but not hMFbs forming spheroid structures in 3D Matrigel® assays. Our analyses confirm the successful isolation of two different cell phenotypes from normal breast tissues. This robust technique provides an inexpensive and accessible approach for mammary cell isolation.
Topics: Breast; Breast Neoplasms; Cell Line; Epithelial Cells; Female; Humans; Stromal Cells; Tumor Microenvironment
PubMed: 34837767
DOI: 10.1016/j.ejcb.2021.151187 -
The EMBO Journal Jul 2019Breast cancer prevention is daunting, yet not an unsurmountable goal. Mammary stem and progenitors have been proposed as the cells-of-origin in breast cancer. Here, we... (Review)
Review
Breast cancer prevention is daunting, yet not an unsurmountable goal. Mammary stem and progenitors have been proposed as the cells-of-origin in breast cancer. Here, we present the concept of limiting these breast cancer precursors as a risk reduction approach in high-risk women. A wealth of information now exists for phenotypic and functional characterization of mammary stem and progenitor cells in mouse and human. Recent work has also revealed the hormonal regulation of stem/progenitor dynamics as well as intrinsic lineage distinctions between mammary epithelial populations. Leveraging these insights, molecular marker-guided chemoprevention is an achievable reality.
Topics: Animals; Biomarkers, Tumor; Breast Neoplasms; Female; Humans; Mammary Glands, Animal; Mammary Glands, Human; Mice; Signal Transduction; Stem Cells
PubMed: 31267556
DOI: 10.15252/embj.2018100852