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Nature Communications Sep 2019Myoepithelial cells play key roles in normal mammary gland development and in limiting pre-invasive to invasive breast tumor progression, yet their differentiation and...
Myoepithelial cells play key roles in normal mammary gland development and in limiting pre-invasive to invasive breast tumor progression, yet their differentiation and perturbation in ductal carcinoma in situ (DCIS) are poorly understood. Here, we investigated myoepithelial cells in normal breast tissues of BRCA1 and BRCA2 germline mutation carriers and in non-carrier controls, and in sporadic DCIS. We found that in the normal breast of non-carriers, myoepithelial cells frequently co-express the p63 and TCF7 transcription factors and that p63 and TCF7 show overlapping chromatin peaks associated with differentiated myoepithelium-specific genes. In contrast, in normal breast tissues of BRCA1 mutation carriers the frequency of p63TCF7 myoepithelial cells is significantly decreased and p63 and TCF7 chromatin peaks do not overlap. These myoepithelial perturbations in normal breast tissues of BRCA1 germline mutation carriers may play a role in their higher risk of breast cancer. The fraction of p63TCF7 myoepithelial cells is also significantly decreased in DCIS, which may be associated with invasive progression.
Topics: Animals; BRCA1 Protein; BRCA2 Protein; Carcinoma, Ductal, Breast; Cell Line, Tumor; Cell Proliferation; Female; Fluorescent Antibody Technique; Germ-Line Mutation; Humans; Immunohistochemistry; Mice; Mutation; T Cell Transcription Factor 1; Transcription Factors; Tumor Suppressor Proteins
PubMed: 31519911
DOI: 10.1038/s41467-019-12125-5 -
The Ocular Surface Jul 2023Epithelial-mesenchymal transition (EMT) constitutes an important pathway in organ fibrosis seen in the lungs, liver, eye, and salivary glands. This review summarizes the... (Review)
Review
Epithelial-mesenchymal transition (EMT) constitutes an important pathway in organ fibrosis seen in the lungs, liver, eye, and salivary glands. This review summarizes the EMT observed within the lacrimal gland during its development, tissue damage and repair along with possible translational implications. Existing animal and human studies have reported the increased expression of EMT regulators i.e., transcription factors like Snail, TGF-β1 within the lacrimal glands, and a possible role of reactive oxygen species, which might be initiating the cascade of EMT. In these studies, EMT is typically detected by reduced E-cadherin expression in the epithelial cells and increased Vimentin and Snail expression within the lacrimal glands' myoepithelial or ductal epithelial cells. Other than specific markers, electron microscopic evidence of disrupted basal lamina, increased collagen deposition, reorganised cytoskeleton of myoepithelial cells also indicated EMT. Very few studies have shown myoepithelial cells to be the cells transitioning into mesenchymal cells with increased extracellular matrix deposition within the lacrimal glands. EMT in animal models seemed reversible as glands got repaired after damage with IL-1α injection or duct ligation and transiently used the EMT as a means for tissue repair. The EMT cells also expressed nestin, a marker for progenitor cells in a rabbit duct ligation model. However, lacrimal glands of ocular graft versus host disease and IgG4 dacryoadenitis demonstrate irreversible acinar atrophy along with signs of EMT-fibrosis, reduced E-cadherin, and increased Vimentin and Snail expression. Future studies exploring the molecular mechanisms of EMT and thereby developing targeted therapies capable of transforming the mesenchymal cells into epithelial cells or blocking the EMT might help in the restoration of the lacrimal gland function.
Topics: Animals; Humans; Rabbits; Lacrimal Apparatus; Epithelial-Mesenchymal Transition; Vimentin; Fibrosis; Cadherins; Morphogenesis; Epithelial Cells
PubMed: 37321448
DOI: 10.1016/j.jtos.2023.06.008 -
Cell Death and Differentiation Feb 2023Salivary glands consist of several epithelial cell types of distinct lineages and functional characteristics that are established by directed differentiation programs of...
Salivary glands consist of several epithelial cell types of distinct lineages and functional characteristics that are established by directed differentiation programs of resident stem and progenitor cells. We have shown that ΔNp63, a crucial transcriptional regulator of stem/progenitor cells, is enriched in both the basal and myoepithelial cell (MEC) populations and that ΔNp63 positive cells maintain all the descendent epithelial cell lineages of the adult mouse salivary glands (mSGs). Although this pivotal role of ΔNp63 in driving the broader epithelial cell fate and identity in the mSG has been demonstrated, how ΔNp63 functions specifically in the commitment and differentiation of the MEC population is less understood. Using multiple genetic mouse models that allow for cell tracing, we show that ΔNp63 is critical in maintaining and renewing MECs, in part through the transcriptional regulation of Acta2 gene expression, a defining marker of this cell population. We demonstrate that during adult mSG homeostasis, ΔNp63 enriched MECs function as bipotent progenitor cells that maintain not only the MEC population, but also the distinctly different ductal cell lineages. The fidelity of this process is dependent on ΔNp63 expression, since MEC-specific ablation of ΔNp63 results in altered MEC differentiation and affects cellular plasticity resulting in aberrant differentiation of the intercalated ducts and acinar cells. In contrast, we find that the contribution of MECs to ductal and acinar cell regeneration following severe injury is independent of ΔNp63. Our observations offer new insights into cellular mechanisms driving MEC fate choices and differentiation programs in the context of salivary gland homeostasis and in response to injury and regeneration. Long term, these findings have implications for better treatment of salivary gland dysfunction through stem cell-based approaches.
Topics: Animals; Mice; Cell Differentiation; Cell Lineage; Epithelial Cells; Salivary Glands; Stem Cells; Trans-Activators
PubMed: 36526896
DOI: 10.1038/s41418-022-01101-0 -
Matrix Biology : Journal of the... Aug 2023Proteases have long been associated with cancer progression, due to their ability to facilitate invasion upon matrix remodelling. However, proteases are not simply...
Proteases have long been associated with cancer progression, due to their ability to facilitate invasion upon matrix remodelling. However, proteases are not simply degraders of the matrix, but also play fundamental roles in modulating cellular behaviour through the proteolytic processing of specific substrates. Indeed, proteases can elicit both pro- and anti- tumorigenic effects depending on context. Using a heterocellular spheroid model of breast cancer progression, we demonstrate the repressive function of myoepithelial ADAMTS3, with its loss directing myoepithelial-led invasion of luminal cells through a physiologically relevant matrix. Degradomic analysis, using terminal amine isotopic labelling of substrates (TAILS), combined with functional assays, implicate ADAMTS3 as a mediator of fibronectin degradation. We show further that loss of ADAMTS3 enhances levels of fibronectin in the microenvironment, promoting invasion through canonical integrin α5β1 activation. Our data highlight a tumour suppressive role for ADAMTS3 in early stage breast cancer, and contribute to the growing evidence that proteases can restrain cancer progression.
Topics: Female; Humans; Breast; Breast Neoplasms; Cell Line, Tumor; Fibronectins; Peptide Hydrolases; Tumor Microenvironment
PubMed: 37336268
DOI: 10.1016/j.matbio.2023.06.005 -
Breast Cancer Research : BCR Oct 2018Amphiregulin (AREG), a ligand of the epidermal growth factor receptor, is not only essential for proper mammary ductal development, but also associated with breast...
BACKGROUND
Amphiregulin (AREG), a ligand of the epidermal growth factor receptor, is not only essential for proper mammary ductal development, but also associated with breast cancer proliferation and growth. In the absence of AREG, mammary ductal growth is stunted and fails to expand. Furthermore, suppression of AREG expression in estrogen receptor-positive breast tumor cells inhibits in-vitro and in-vivo growth.
METHODS
We crossed AREG-null (AREG) mice with the murine luminal B breast cancer model, MMTV-PyMT (PyMT), to generate spontaneous breast tumors that lack AREG (AREG PyMT). We evaluated tumor growth, cytokeratin-8 (K8)-positive luminal cells, cytokeratin-14 (K14)-positive myoepithelial cells, and expression of AREG, Ki67, and PyMT. Primary myoepithelial cells from nontumor-bearing AREG mice underwent fluorescence-activated cell sorting and were adapted to culture for in-vitro coculture studies with AT-3 cells, a cell line derived from C57Bl/6 PyMT mammary tumors.
RESULTS
Intriguingly, PyMT-induced lesions progress more rapidly in AREG mice than in AREG mice. Quantification of K8 luminal and K14 myoepithelial cells in non-PyMT AREG mammary glands showed fewer K14 cells and a thinner myoepithelial layer. Study of AT-3 cells indicated that coculture with myoepithelial cells or exposure to AREG, epidermal growth factor, or basic fibroblast growth factor can suppress PyMT expression. Late-stage AREG PyMT tumors are significantly less solid in structure, with more areas of papillary and cystic growth. Papillary areas appear to be both less proliferative and less necrotic. In The Cancer Genome Atlas database, luminal-B invasive papillary carcinomas have lower AREG expression than luminal B invasive ductal carcinomas.
CONCLUSIONS
Our study has revealed a previously unknown role of AREG in myoepithelial cell development and PyMT expression. AREG expression is essential for proper myoepithelial coverage of mammary ducts. Both AREG and myoepithelial cells can suppress PyMT expression. We find that lower AREG expression is associated with invasive papillary breast cancer in both the MMTV-PyMT model and human breast cancer.
Topics: Amphiregulin; Animals; Antigens, Polyomavirus Transforming; Cell Line, Tumor; Cell Proliferation; Epithelial Cells; Female; Humans; Mammary Glands, Animal; Mammary Neoplasms, Experimental; Mammary Tumor Virus, Mouse; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neoplasm Invasiveness; Polyomavirus
PubMed: 30367629
DOI: 10.1186/s13058-018-1057-0 -
Translational Oncology Sep 2023Active breast cancer-associated fibroblasts (CAFs) promote tumor growth and spread, and like tumor cells they are also heterogeneous with various molecular sub-types and...
BACKGROUND
Active breast cancer-associated fibroblasts (CAFs) promote tumor growth and spread, and like tumor cells they are also heterogeneous with various molecular sub-types and different pro-tumorigenic capacities.
METHODS
We have used immunoblotting as well as quantitative RT-PCR to assess the expression of various epithelial/mesenchymal as well as stemness markers in breast stromal fibroblasts. Immunofluorescence was utilized to assess the level of different myoepithelial and luminal markers at the cellular level. Flow cytometry allowed to determine the proportion of CD44- and ALDH1-positive breast fibroblasts, while sphere formation assay was used to test the ability of these cells to form mammospheres.
RESULTS
We have shown here that IL-6-dependent activation of breast and skin fibroblasts promotes mesenchymal-to-epithelial transition and stemness in a STAT3- and p16-dependent manner. Interestingly, most primary CAFs isolated from breast cancer patients exhibited such transition and expressed lower levels of the mesenchymal markers N-cadherin and vimentin as compared to their adjacent normal fibroblasts (TCFs) isolated from the same patients. We have also shown that some CAFs and IL-6-activated fibroblasts express high levels of the myoepithelial markers cytokeratin 14 and CD10. Interestingly, 12 CAFs isolated from breast tumors showed higher proportions of CD24/CD44 and ALDH cells, compared to their corresponding TCF cells. These CD44 cells have higher abilities to form mammospheres and to enhance cell proliferation of breast cancer cells in a paracrine manner relative to their corresponding CD44 cells.
CONCLUSION
Together, the present findings show novel characteristics of active breast stromal fibroblasts, which exhibit additional myoepithelial/progenitor features.
PubMed: 37329829
DOI: 10.1016/j.tranon.2023.101721 -
Head and Neck Pathology Sep 2022Pleomorphic adenoma (PA) is the most common biphasic type of salivary gland tumour to arise in adults. It is a biphasic tumour composed of both luminal (ductal) cells...
Pleomorphic adenoma (PA) is the most common biphasic type of salivary gland tumour to arise in adults. It is a biphasic tumour composed of both luminal (ductal) cells and abluminal (basal and myoepithelial) cells. Other biphasic salivary gland type tumours, both benign and malignant, can mimic PA, especially on small biopsies. Previous studies have shown that glial fibrillary acidic protein (GFAP) is preferentially expressed in PA and can be useful in the distinction from other salivary gland tumours. However, most of these studies were performed on a small subset of tumour types at a time when the classification of salivary gland type tumours was less refined. The purpose of this study was to assess the expression of glial fibrillary acidic protein (GFAP) in a broad group of both benign and malignant salivary gland tumours. The expression of GFAP was assessed in 99 tumours including 54 PAs, 5 basal cell adenomas, 1 myoepitheliomas, 5 adenoid cystic carcinomas, 6 epithelial-myoepithelial carcinomas (EMCA), 6 mucoepidermoid carcinomas, 7 salivary duct carcinomas, 1 adenocarcinomas NOS, 2 myoepithelial carcinomas, 4 basal cell adenocarcinomas, 5 acinic cell carcinomas and 3 polymorphous adenocarcinomas. Of the malignant cases, 8 were classified as carcinomas ex PA. GFAP was also assessed in 19 concurrent biopsy specimens. GFAP was expressed in the resections of 51 PAs examined (94%). Expression was predominantly strong and diffusely seen in myoepithelial cells. Strong and diffuse GFAP expression was also seen in two EMCAs (33%) and one myoepithelial carcinoma (50%). On biopsy specimens, 100% of PAs and basal cell adenomas expressed GFAP. GFAP was also seen in 1 out of 3 carcinomas ex PAs on biopsies. Almost all PAs show strong and diffuse expression of GFAP. In contrast, most malignant neoplasms that can mimic PA on biopsies show only rare, focal expression. Other benign tumours composed of abluminal/myoepithelial cells also show focal expression of GFAP, highlighting the spectrum these tumours share with PA. Overall, the presence of strong and diffuse GFAP expression can favour a benign neoplasm, specifically a PA, on limited biopsy specimens.
Topics: Adenoma; Adenoma, Pleomorphic; Adult; Biomarkers, Tumor; Carcinoma; Carcinoma, Acinar Cell; Glial Fibrillary Acidic Protein; Humans; Immunohistochemistry; Myoepithelioma; Salivary Gland Neoplasms
PubMed: 35064902
DOI: 10.1007/s12105-021-01409-2 -
Applied Immunohistochemistry &... Jul 2015Primary myoepithelial carcinoma of the lung is a rare neoplasm with only 8 cases reported in the English literature to date. Myoepithelial carcinomas of the lung are... (Review)
Review
Primary myoepithelial carcinoma of the lung is a rare neoplasm with only 8 cases reported in the English literature to date. Myoepithelial carcinomas of the lung are thought to arise from submucosal bronchial glands and have morphologic features similar to their salivary gland counterparts. The pathologic features and immunohistochemical profile of this tumor have not yet been summarized in the literature. Our objective is to review the clinicopathologic features and immunohistochemistry of these tumors.
Topics: Aged; Asian People; Biomarkers, Tumor; Epithelial Cells; Female; Humans; Immunohistochemistry; Lung Neoplasms; Male; Middle Aged; Myoepithelioma; Neoplasm Proteins; Rare Diseases; Salivary Glands; White People
PubMed: 25517870
DOI: 10.1097/PAI.0000000000000113 -
Journal of Oral Pathology & Medicine :... Sep 2020There has been great interest recently in the mechanisms of cell-to-cell communication through microvesicles (MV). These structures are produced by many different cell...
BACKGROUND
There has been great interest recently in the mechanisms of cell-to-cell communication through microvesicles (MV). These structures are produced by many different cell types and can modulate cellular activity by induction of epigenetic alterations. These vesicles may promote tumor mass increase either by stimulating cell proliferation via growth factors or by inhibiting apoptosis, which reinforces the role of such vesicles as important modulators of tumor progression.
METHODS
The present in vitro study aimed to characterize MV derived from malignant neoplastic epithelial cell cultures (EP) and their effect on the expression of apoptosis/autophagy and invasion related genes of benign myoepithelial (Myo) cell cultures.
RESULTS
The results revealed round structures with a mean size of 153.6 (±0.2) nm, with typical MV morphology. CD63 quantification indicated that EP cell culture at 70%-80% confluence secreted 3.088 × 10 MV/mL. Overall, Myo exposed to MVs derived from EP showed both up- and downregulation of tumorigenesis promoting genes. MVs from EP cells promoted cell death of Myo cells and positively modulate BAX, SURVIVIN, LC3B, MMP-2, and MMP-9 expression. Furthermore, an increasing of MMP-2 and MMP-9 secretion by Myo was observed after MV exposure.
CONCLUSIONS
These findings suggest that MVs from EP modulate autophagy of Myo cells, which may, in part, explain the disappearance of these cells in in situ areas of invasive carcinoma ex-pleomorphic adenoma. Additionally, the overexpression of MMPs contributes to the development of an invasive phenotype of Myo cells, which could favor the dissolution of the basement membrane during tumorigenesis process.
Topics: Adenoma, Pleomorphic; Autophagy; Carcinoma, Squamous Cell; Cell Death; Epithelial Cells; Humans
PubMed: 32453894
DOI: 10.1111/jop.13037 -
Cell Death & Disease May 2017Protein tyrosine phosphatase 1B (PTP1B) is a well-known inhibitor of insulin signaling pathways and inhibitors against PTP1B are being developed as promising drug...
Protein tyrosine phosphatase 1B (PTP1B) is a well-known inhibitor of insulin signaling pathways and inhibitors against PTP1B are being developed as promising drug candidates for treatment of obesity. PTP1B has also been linked to breast cancer both as a tumor suppressor and as an oncogene. Furthermore, PTP1B has been shown to be a regulator of cell adhesion and migration in normal and cancer cells. In this study, we analyzed the PTP1B expression in normal breast tissue, primary breast cells and the breast epithelial cell line D492. In normal breast tissue and primary breast cells, PTP1B is widely expressed in both epithelial and stromal cells, with highest expression in myoepithelial cells and fibroblasts. PTP1B is widely expressed in branching structures generated by D492 when cultured in 3D reconstituted basement membrane (3D rBM). Inhibition of PTP1B in D492 and another mammary epithelial cell line HMLE resulted in reduced cell proliferation and induction of anoikis. These changes were seen when cells were cultured both in monolayer and in 3D rBM. PTP1B inhibition affected cell attachment, expression of cell adhesion proteins and actin polymerization. Moreover, epithelial to mesenchymal transition (EMT) sensitized cells to PTP1B inhibition. A mesenchymal sublines of D492 and HMLE (D492M and HMLEmes) were more sensitive to PTP1B inhibition than D492 and HMLE. Reversion of D492M to an epithelial state using miR-200c-141 restored resistance to detachment induced by PTP1B inhibition. In conclusion, we have shown that PTP1B is widely expressed in the human breast gland with highest expression in myoepithelial cells and fibroblasts. Inhibition of PTP1B in D492 and HMLE affects cell-cell adhesion and induces anoikis-like effects. Finally, cells with an EMT phenotype are more sensitive to PTP1B inhibitors making PTP1B a potential candidate for further studies as a target for drug development in cancer involving the EMT phenotype.
Topics: Anoikis; Cell Adhesion; Cell Communication; Cell Line; Epithelial Cells; Female; Gene Expression Regulation, Enzymologic; Humans; Mammary Glands, Human; Protein Tyrosine Phosphatase, Non-Receptor Type 1
PubMed: 28492548
DOI: 10.1038/cddis.2017.177