Project description:The airway mucociliary epithelium is consituted of three main cell types : columnar ciliated plus secretory cells and basal cells. Columnar cells are represented by a great majority of ciliated cells. We used Cell sorting by FACSaria to separate basal cells from ciliated and secreting columnar cells. Then, we performed microRNA high throughput sequencing to investigate the specific signature of microRNA of basal and columnar cells.
Project description:The airway mucociliary epithelium is consituted of three main cell types : columnar ciliated plus secretory cells and basal cells. Columnar cells are represented by a great majority of ciliated cells. We used Cell sorting by FACSaria to separate basal cells from ciliated and secreting columnar cells. Then, we performed microRNA high throughput sequencing to investigate the specific signature of microRNA of basal and columnar cells. miRNAs high throughput sequencing profiling of human nasal mucosa: basals cells (B) and columnars (C) cells for 3 donors.
Project description:Columnar cell hyperplasia (CCH) is the first histologically identifiable lesion in the breast with premalignant potential. Altered miRNA expression in the stroma surrounding CCH compared to normal tissue was discovered. The effect of upregulation of one specific miRNA was investigated by gene expression array in human mammary fibroblasts as well as in epithelial CCH cells coculterd with miR-132 oversexpressing human mammary fibroblasts. We used microarrays to detail the effects of miR-132 in human mammary fibroblasts and identified multiple altered genes and gene pathways both in the fibroblasts and in cocultured human mammary epithelial CCH cells.
Project description:Columnar cell hyperplasia (CCH) is the earliest histologically identifiable breast lesion linked to cancer progression and is characterized by increased proliferation, decreased apoptosis and elevated oestrogen receptor a expression. The mechanisms underlying the initiation of these lesions have not been clarified but might involve early and fundamental changes in cancer progression. MiRNAs are key regulators of several biological processes, acting by influencing the posttranscriptional regulation of numerous targets, thus making miRNAs potential candidates in cancer initiation. Here we have defined novel epithelial as well as stromal miRNA signatures from columnar cell hyperplasia lesions compared to normal terminal duct lobular units by using microdissection and miRNA microarrays. MiR-27a, miR-92a and let-7c were among the identified downregulated epithelial miRNAs and their functions were delineated in unique CCH derived cells suggesting pro-apoptotic and anti-proliferative properties for the selected miRNAs and that downregulation of let-7c in CCH cells potentially increased proliferation via Myb. MiR-132 was upregulated in the stroma surrounding CCH compared to stoma surrounding TDLUs, and overexpression of miR-132 in immortalized fibroblasts and in fibroblasts co-cultured with epithelial CCH cells caused substantial expression changes. Global miRNA expression was also examined both epithelial and stroma of one patient displaying TDLU, CCH and additional invasive breast cancer. The miRNA signatures identified in CCH indicate concordant early changes in the epithelial and stromal compartment of CCH and could represent early key alterations in breast cancer progression that potentially could be targeted in novel prevention or treatment schedules.
Project description:The small intestinal epithelium is the most rapidly self-renewing tissue of mammals. Proliferative cells are confined to crypts, while differentiated cell types predominantly occupy the villi. We recently demonstrated the existence of a long-lived pool of cycling stem cells defined by Lgr5 expression and intermingled with post-mitotic Paneth cells at crypt bottoms. We have now determined a gene signature for these so called Crypt Base Columnar (CBC) cells. One of the genes within this stem cell signature is the Wnt target Ascl2. Transgenic expression of the Ascl2 transcription factor throughout the intestinal epithelium induces crypt hyperplasia and de novo crypt formation on villi. Induced deletion of the Ascl2 gene in adult small intestine leads to disappearance of the CBC stem cells within days. The combined results from these gain- and loss-of-function experiments imply that Ascl2 controls intestinal stem cell fate. Keywords: expression profiling
Project description:Enlargement of normal terminal duct lobular units (TDLUs) by hyperplastic columnar epithelial cells is one of the most common abnormalities of growth in the adult female human breast. These hyperplastic enlarged lobular units (HELUs) are important clinically as the earliest histologically identifiable potential precursor of breast cancer. The causes of the hyperplasia are unknown but may include estrogen-simulated growth mediated by estrogen receptor alpha, which is highly elevated in HELUs and may be fundamental to their development. This study used DNA microarray technology and RNA from microdissected pure epithelial cells to learn more about changes in gene expression and molecular pathways associated with the development of HELUs from TDLUs Keywords: Identification of early cancer precursors
Project description:The cellular origin of cervical cancers remains unclear. Revealing molecular details of transformation in this tissue has been hampered by the lack of culture systems, resembling the in vivo cervical architecture. Here we established a long-term in vitro 3D cervical organoid model derived from stem cells of human or mouse cervical tissue which recapitulates the in vivo stratified ectocervical and columnar endocervical epithelium. Stratified and columnar cervical epithelia arise from two discrete unipotent stem cell populations of the endocervix. Unique stem cell signatures reveal a dependency on intrinsic Notch and Wnt microenvironmental signals. The genetic signatures of KRT5+ stratified vs KRT7+ columnar cervical cells establish discrete groups of cervical cancer of the squamous and adenocarcinoma types, respectively. Cervical tissue morphology is guided by the interplay of two discrete unipotent cervical stem cell populations and the spatio-temporal distribution of signals from the stroma.
Project description:The cellular origin of cervical cancers remains unclear. Revealing molecular details of transformation in this tissue has been hampered by the lack of culture systems, resembling the in vivo cervical architecture. Here we established a long-term in vitro 3D cervical organoid model derived from stem cells of human or mouse cervical tissue which recapitulates the in vivo stratified ectocervical and columnar endocervical epithelium. Stratified and columnar cervical epithelia arise from two discrete unipotent stem cell populations of the endocervix. Unique stem cell signatures reveal a dependency on intrinsic Notch and Wnt microenvironmental signals. The genetic signatures of KRT5+ stratified vs KRT7+ columnar cervical cells establish discrete groups of cervical cancer of the squamous and adenocarcinoma types, respectively. Cervical tissue morphology is guided by the interplay of two discrete unipotent cervical stem cell populations and the spatio-temporal distribution of signals from the stroma.
Project description:Enlargement of normal terminal duct lobular units (TDLUs) by hyperplastic columnar epithelial cells is one of the most common abnormalities of growth in the adult female human breast. These hyperplastic enlarged lobular units (HELUs) are important clinically as the earliest histologically identifiable potential precursor of breast cancer. The causes of the hyperplasia are unknown but may include estrogen-simulated growth mediated by estrogen receptor alpha, which is highly elevated in HELUs and may be fundamental to their development. This study used DNA microarray technology and RNA from microdissected pure epithelial cells to learn more about changes in gene expression and molecular pathways associated with the development of HELUs from TDLUs Experiment Overall Design: Samples for the microarray studies were derived from 8 formalin-fixed paraffin-embedded tissue (FFPET) biopsies containing paired normal TDLUs and well-developed HELUs from non-cancerous adult female human breasts obtained within the past 3 years. Populations of nearly pure (>95%) epithelial cells were isolated from the TDLUs and HELUs in each biopsy (approximately 25,000 cells/sample) by laser capture microdissection (LCM)