Project description:RNA-seq of embryonic mammary progenitor cell lines. Embryonic mammary progenitor cell (eMPC) clones were derived from E12.5-stage mammary organs. After microdissection, mammary primordial 3 was cultured on thick basement membrane extract for 4 weeks. After enzymatic dissociation eMPC swere plated and expanded in 2D culture to obtain a pool of eMPCs. eMPC cells were subject to single cell sorting using FACS. Clones were expanded as single-cell derived clones (eMPC1, 2, etc.) to create the eighteen single cell-derived clones described in this study.
Project description:CRISPR/Cas9-mediated gene targeting of Sox9 from embryonic mammary progenitors cell line eMPC1. Part of a study to assess the effect of Sox9 ablation on embryonic mammary progenitor cell fate and function.
Project description:The mammary epithelium depends on specific lineages and their stem and progenitor function to accommodate hormone-triggered physiological demands in the adult female. Perturbations of these lineages underpin breast cancer risk, yet our understanding of normal mammary cell composition is incomplete. Here, we build a multimodal resource for the adult gland through comprehensive profiling of primary cell epigenomes, transcriptomes, and proteomes. We define systems-level relationships between chromatin–DNA–RNA–protein states, identify lineage-specific DNA methylation of transcription factor binding sites, and pinpoint proteins underlying progesterone responsiveness. Comparative proteomics of estrogen and progesterone receptor–positive and –negative cell populations, extensive target validation, and drug testing lead to discovery of stem and progenitor cell vulnerabilities. Top epigenetic drugs exert cytostatic effects; prevent adult mammary cell expansion, clonogenicity, and mammopoiesis; and deplete stem cell frequency. Select drugs also abrogate human breast progenitor cell activity in normal and high-risk patient samples. This integrative computational and functional study provides fundamental insight into mammary lineage and stem cell biology.
PMID: 29921600 (Table S5 and Table S7)
Project description:The mammary primordium represents the earliest evidence of commitment to the mammary lineage. The primordium forms via inductive tissue interactions between its constitutive tissues, the mesenchyme and epithelium. Here, we describe an analysis of the transcriptome of the mammary bud epithelium and its associated mesenchyme, two distinct cellular compartments that comprise the mammary primordium. Using network analysis, we found candidate mediators of mammary cell fate, differentiation and progenitor cell function that signal from mammary lineage inception during embryogenesis through postnatal development. Genetic features of mammary primordial cells overlapping with human breast progenitor cells identified potential regulators of key progenitor cell functions conserved across species. These results provide new insights into genetic regulatory mechanisms of mammary and in particular novel regulators of stromal-epithelial communications.
Project description:Mammary alveologenesis is abrogated in the absence of the transcription factors STAT5A/5B that mediate cytokine signaling. To reveal the underlying causes for this developmental block we studied mammary stem and progenitor cells. While loss of STAT5A/5B did not affect the stem cell population and their ability to form mammary ducts, luminal progenitors were greatly reduced and unable to form alveoli during pregnancy. Temporally-controlled expression of transgenic STAT5A in mammary epithelium lacking STAT5A/5B restored the luminal progenitor population and rescued alveologenesis in a reversible fashion in vivo. Taken together, STAT5A is necessary and sufficient for the establishment of luminal progenitor cells. The mammary tissues from two mice of each genotype were collected 6 days (sample 9 and 11 were WT)
Project description:Mammary alveologenesis is abrogated in the absence of the transcription factors STAT5A/5B that mediate cytokine signaling. To reveal the underlying causes for this developmental block we studied mammary stem and progenitor cells. While loss of STAT5A/5B did not affect the stem cell population and their ability to form mammary ducts, luminal progenitors were greatly reduced and unable to form alveoli during pregnancy. Temporally-controlled expression of transgenic STAT5A in mammary epithelium lacking STAT5A/5B restored the luminal progenitor population and rescued alveologenesis in a reversible fashion in vivo. Taken together, STAT5A is necessary and sufficient for the establishment of luminal progenitor cells.
Project description:Five molecular subtypes (Luminal A/B, HER2-enriched, Basal-like, and Claudin-low) with clinical implications have been identified. In this report, we evaluated molecular and phenotypic relationships of a large in vitro panel of human breast cancer cell lines (BCCLs), human mammary fibroblasts (HMFs) and human mammary epithelial cells (HMECs) with (1) breast tumors, (2) normal breast cell-enriched subpopulations and (3) human embryonic stem cells (hESCs) and bone marrow-derived mesenchymal stem cells (hMSC). First, by integrating genomic data of 337 breast samples with 93 cell lines we were able to identify all the intrinsic tumor subtypes in vitro, except for the Luminal A. Secondly, we observed that cell lines recapitulate the differentiation hierarchy observed in the mammary gland, with Claudin-low BCCLs and HMFs cells showing a stromal phenotype, HMECs showing a mammary stem cell/bipotent progenitor phenotype, Basal-like cells showing a luminal progenitor phenotype, and Luminal B cells showing a luminal phenotype. Thirdly, we identified Basal-like and highly migratory Claudin-low subpopulations of cells within a subset of triple-negative BCCLs (SUM149PT, HCC1143 and HCC38). Interestingly, both subpopulations within SUM149PT where found to have Tumor Initiating Cell (TIC) features, but the Basal-like subpopulation grew faster than the Claudin-low subpopulation. Finally, Claudin-low BCCLs were found to resemble the phenotype of hMSCs, whereas hESCs cells were found to have an epithelial phenotype without basal and luminal differentiation. The results presented here should help improve our understanding of the cell line model system through the appropriate pairing of cell lines with relevant in vivo tumor and normal cell counterparts.