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Nature Communications Oct 2023Exocrine acinar cells in salivary glands (SG) are critical for oral health and loss of functional acinar cells is a major clinical challenge. Fibroblast growth factor...
Exocrine acinar cells in salivary glands (SG) are critical for oral health and loss of functional acinar cells is a major clinical challenge. Fibroblast growth factor receptors (FGFR) are essential for early development of multiple organs, including SG. However, the role of FGFR signaling in specific populations later in development and during acinar differentiation are unknown. Here, we use scRNAseq and conditional deletion of murine FGFRs in vivo to identify essential roles for FGFRs in craniofacial, early SG development and progenitor function during duct homeostasis. Importantly, we also discover that FGFR2 via MAPK signaling is critical for seromucous acinar differentiation and secretory gene expression, while FGFR1 is dispensable. We show that FGF7, expressed by myoepithelial cells (MEC), activates the FGFR2-dependent seromucous transcriptional program. Here, we propose a model where MEC-derived FGF7 drives seromucous acinar differentiation, providing a rationale for targeting FGFR2 signaling in regenerative therapies to restore acinar function.
Topics: Animals; Mice; Cell Differentiation; Homeostasis; Orosomucoid; Salivary Glands; Signal Transduction
PubMed: 37838739
DOI: 10.1038/s41467-023-42243-0 -
Indian Journal of Otolaryngology and... Oct 2019Myoepitheliomas are rare tumours of salivary glands arising from myoepithelial cells, which are normal constituent of the salivary acini and ducts and are found between...
Myoepitheliomas are rare tumours of salivary glands arising from myoepithelial cells, which are normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. The most common site of origin of Myoepitheliomas are the salivary glands and rarely other sites in the head and neck have been described in literature. Myoepithelioma arising from parapharyngeal space provide both a diagnostic and therapeutic challenge. We present such a case and discuss its diagnostic and therapeutic aspects.
PubMed: 31742043
DOI: 10.1007/s12070-018-1488-z -
Journal of Clinical Medicine Jul 2022Pleomorphic adenoma (PA) is a localized tumor that presents pleomorphic or mixed characteristics of epithelial origin and is interwoven with mucoid tissue, myxoid... (Review)
Review
Pleomorphic adenoma (PA) is a localized tumor that presents pleomorphic or mixed characteristics of epithelial origin and is interwoven with mucoid tissue, myxoid tissue, and chondroid masses. The literature reported that PA most often occurs in adults aged 30-60 years and is a female predilection; the exact etiology remains unclear. Epithelial-mesenchymal transition (EMT) is the transdifferentiation of stationary epithelial cells primarily activated by a core set of transcription factors (EMT-TFs) involved in DNA repair and offers advantages under various stress conditions. Data have suggested that EMTs represent the basic principle of tissue heterogeneity in PAs, demonstrating the potential of adult epithelial cells to transdifferentiate into mesenchymal cells. It has also been reported that multiple TFs, such as TWIST and SLUG, are involved in EMT in PA and that SLUG could play an essential role in the transition from myoepithelial to mesenchymal cells. Given this background, this review aims to summarize and clarify the involvement of EMT in the development of PA, chondrocyte differentiation, and malignant transformation to contribute to the fundamental elucidation of the mechanisms underlying EMT.
PubMed: 35887973
DOI: 10.3390/jcm11144210 -
Breast Cancer Research : BCR Sep 2020Breast cancer arises within specific regions in the human breast referred to as the terminal duct lobular units (TDLUs). These are relatively dynamic structures...
BACKGROUND
Breast cancer arises within specific regions in the human breast referred to as the terminal duct lobular units (TDLUs). These are relatively dynamic structures characterized by sex hormone driven cyclic epithelial turnover. TDLUs consist of unique parenchymal entities embedded within a fibroblast-rich lobular stroma. Here, we established and characterized a new human breast lobular fibroblast cell line against its interlobular counterpart with a view to assessing the role of region-specific stromal cues in the control of TDLU dynamics.
METHODS
Primary lobular and interlobular fibroblasts were transduced to express human telomerase reverse transcriptase (hTERT). Differentiation of the established cell lines along lobular and interlobular pathways was determined by immunocytochemical staining and genome-wide RNA sequencing. Their functional properties were further characterized by analysis of mesenchymal stem cell (MSC) differentiation repertoire in culture and in vivo. The cells' physiological relevance for parenchymal differentiation was examined in heterotypic co-culture with fluorescence-activated cell sorting (FACS)-purified normal breast primary luminal or myoepithelial progenitors. The co-cultures were immunostained for quantitative assessment of epithelial branching morphogenesis, polarization, growth, and luminal epithelial maturation. In extension, myoepithelial progenitors were tested for luminal differentiation capacity in culture and in mouse xenografts. To unravel the significance of transforming growth factor-beta (TGF-β)-mediated crosstalk in TDLU-like morphogenesis and differentiation, fibroblasts were incubated with the TGF-β signaling inhibitor, SB431542, prior to heterotypic co-culture with luminal cells.
RESULTS
hTERT immortalized fibroblast cell lines retained critical phenotypic traits in culture and linked to primary fibroblasts. Cell culture assays and transplantation to mice showed that the origin of fibroblasts determines TDLU-like and ductal-like differentiation of epithelial progenitors. Whereas lobular fibroblasts supported a high level of branching morphogenesis by luminal cells, interlobular fibroblasts supported ductal-like myoepithelial characteristics. TDLU-like morphogenesis, at least in part, relied on intact TGF-β signaling.
CONCLUSIONS
The significance of the most prominent cell type in normal breast stroma, the fibroblast, in directing epithelial differentiation is largely unknown. Through establishment of lobular and interlobular fibroblast cell lines, we here demonstrate that epithelial progenitors are submitted to stromal cues for site-specific differentiation. Our findings lend credence to considering stromal subtleties of crucial importance in the development of normal breast and, in turn, breast cancer.
Topics: Adult; Animals; Breast; Breast Neoplasms; Cell Differentiation; Cell Line; Coculture Techniques; Epithelial Cells; Female; Fibroblasts; Humans; Mice; Mice, Inbred NOD; Mice, SCID; Stem Cells; Stromal Cells; Xenograft Model Antitumor Assays; Young Adult
PubMed: 32993755
DOI: 10.1186/s13058-020-01344-0 -
European Journal of Breast Health Jul 2021This study aimed to find out valuable parameters that predict the nature of breast papillary lesions before excision, and we compared our results with those in the...
OBJECTIVE
This study aimed to find out valuable parameters that predict the nature of breast papillary lesions before excision, and we compared our results with those in the literature.
MATERIALS AND METHODS
We reviewed the medical records and pathology slides of patients diagnosed with papillary neoplasm after undergoing a core-needle biopsy between 2010 and 2020, who, subsequently, underwent surgical excision in a single tertiary care institution. The core biopsy results and pathology results of excision materials were compared with the radiological, pathological, and demographic findings.
RESULTS
A total of 51 patients were included in the study. According to the excision results, the patients were divided into two groups: the atypical group, which included 20 patients (39.3%), and the benign group, which included 31 patients (61.7%). The results of the core biopsy showed that the loss of myoepithelial cell layer was identified in 18 patients in the atypical group, while it was present in all patients in the benign group. Tumor sizes were larger and patient ages were older in the atypical group compared with the benign group. No significant difference was found between atypical and benign groups in terms of breast imaging-reporting and data system (BI-RADS) classification and location (right vs left; central vs peripheral). The upgrade rate was between 0% and 16% in literature, while it was 4% in our study.
CONCLUSION
There is no consensus on whether patients diagnosed with papillary neoplasia as a result of core biopsy will undergo excision. According to our results, patients with following criteria should have their lesions excised: those who are advanced in age, those who are diagnosed with a papillary lesion as a result of core biopsies with loss of myoepithelial cell layer, and those who are diagnosed with large-sized lesions without loss of myoepithelial cell layer. Patients diagnosed with small-sized lesions without loss of myoepithelial cell layer and who are young in age are to be followed up without the need for lesion excision. The lesions should be adequately sampled.
PubMed: 34263154
DOI: 10.4274/ejbh.galenos.2021.6101 -
Acta Histochemica May 2020The lacrimal sac (LS) empties in the nasolacrimal duct to drain the tears in the inferior nasal meatus. Different studies indicated the role of the lacrimal pump in the...
The lacrimal sac (LS) empties in the nasolacrimal duct to drain the tears in the inferior nasal meatus. Different studies indicated the role of the lacrimal pump in the lacrimal drainage. Although controversial, the lacrimal pump mechanism is an extrinsic one, either active, or passive. An intrinsic contractile potential of the LS was not documented previously. We thus aimed a retrospective immunohistochemical study to test the alpha-smooth muscle actin (α-SMA) and h-caldesmon expression in the LS wall. We used archived paraffin-embedded samples of LS from ten adult patients. The α-SMA + phenotype was detected in basal epithelial cells, in subepithelial ribbons of stromal cells, in vascular smooth muscle cells, as well as in pericytes. H-caldesmon was exclusively expressed in pericytes, vascular smooth muscle cells and myoepithelial cells of the subepithelial glands. The most striking feature we found in all samples was a consistent stromal network of α-SMA+/h-caldesmon- myofibroblasts. This finding supports an intrinsic scaffold useful for the lacrimal pump.
Topics: Actins; Calmodulin-Binding Proteins; Epithelial Cells; Female; Humans; Lacrimal Apparatus; Male; Middle Aged; Muscle Contraction; Myocytes, Smooth Muscle; Myofibroblasts; Pericytes; Retrospective Studies
PubMed: 32156483
DOI: 10.1016/j.acthis.2020.151536 -
Frontiers in Ophthalmology 2022In the lacrimal gland, myoepithelial cells (MEC) express muscle contractile proteins such as alpha smooth muscle actin (SMA) and calponin and therefore can contract to...
In the lacrimal gland, myoepithelial cells (MEC) express muscle contractile proteins such as alpha smooth muscle actin (SMA) and calponin and therefore can contract to help expel lacrimal fluid. In a previous study, we demonstrated that lacrimal gland MEC express the oxytocin receptor (OXTR) and they contract under oxytocin (OXT) stimulation. Using NOD and MRL/lpr mice (animal models of Sjogren's syndrome), we reported a decrease in SMA and calponin protein levels plus a decline in acini contraction after stimulation with OXT. It is known that proinflammatory cytokines, such as interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α) or interferon gamma (IFN-γ), can affect OXTR expression and signaling capacity and inhibit MEC contraction. The aim of the current study was to investigate if proinflammatory cytokines are implicated in the loss of MEC contractile ability. Thus, lacrimal gland MEC from a SMA-GFP transgenic mouse were treated with IL-1β (10 ng/ml) for a total of 7 days. At days 0, 2, 4 and 7, GFP intensity, cell size/area, contractile proteins amounts and MEC contraction were assessed. At day 0, control and treated cells showed no differences in GFP intensity and cell size. GFP intensity started to decrease in treated MEC at day 2 (20%; p=0.02), continuing after day 4 (25%; p=0.007) and 7 (30%; p=0.0001). Mean cell area was also reduced at day 2 (34%; p=0.0005), and after 4 (51%; p<0.0001) and 7 days (30%; p=0.0015). The contraction assay at day 2 showed a 70% decrease of contraction in treated MEC (p<0.0001), 73% (p<0.0001) at day 4 and 82% (p=0.0015) at day 7 when compared to control. Levels of contractile proteins were measured on day 7 showing a decrease in SMA and calponin amount in treated MEC compared with the control group (around 30%; p=0.0016 and p=0.0206; respectively). Similar results were observed when TNF-α and IFN-γ were added along with IL-1β. Taken together the present data and those from our previous studies with Sjogren's syndrome mouse models, they strongly suggest that proinflammatory cytokines affect lacrimal gland MEC contractile ability that may account for the reduced tear secretion associated with Sjogren's syndrome dry eye disease.
PubMed: 36147586
DOI: 10.3389/fopht.2022.873486 -
Laboratory Investigation; a Journal of... Jun 2022The histogenesis of pleomorphic adenoma (PA) of the salivary glands remains controversial. PAs are characterized by the transition of epithelial cells to spindled...
The histogenesis of pleomorphic adenoma (PA) of the salivary glands remains controversial. PAs are characterized by the transition of epithelial cells to spindled mesenchymal cells, known as epithelial-mesenchymal transition (EMT). The present study aimed to identify a major EMT-inducing transcription factor (EMT-TF) in PAs. Real-time PCR analysis of SNAIL, SLUG, ZEB1, and TWIST1 demonstrated that only SLUG was significantly upregulated in normal salivary glands and PAs. Combined in situ hybridization for SLUG and multiplex immunohistochemistry for CK19 and P63 revealed that SLUG was specifically expressed in the myoepithelial cells of normal salivary glands. In PAs, SLUG was expressed in neoplastic myoepithelial cells and stromal cells but not in the luminal cells lining the inner layers of tumor glands. SLUG expression showed no correlation with PLAG1 expression, and in vitro experiments demonstrated that PLAG1 suppression in primary cultured PA cells or PLAG1 overexpression in HEK 293 T cells did not affect SLUG levels, indicating that PLAG1 was not involved in the upregulation of SLUG in PAs. The suppression of SLUG expression in cultured PA cells resulted in a morphology change to a less elongated shape and attenuated tumor growth. In addition, SLUG downregulation led to increased E-cadherin and decreased N-cadherin and vimentin expression levels along with decreased migratory activity in cultured PA cells. These findings suggest that SLUG is a major TF that can induce EMT in PAs. In summary, SLUG is specifically and highly expressed in the myoepithelial cells and stromal cells of PAs and is a key regulator of EMT in PAs.
Topics: Adenoma, Pleomorphic; Epithelial-Mesenchymal Transition; HEK293 Cells; Humans; Immunohistochemistry; Snail Family Transcription Factors
PubMed: 35145202
DOI: 10.1038/s41374-022-00739-1 -
Oral Diseases Apr 2024Intraglandular injection of botulinum toxin type A (BoNT/A) effectively treats sialorrhea. Myoepithelial cells (MECs) are essential for salivary secretion. The role of...
OBJECTIVE
Intraglandular injection of botulinum toxin type A (BoNT/A) effectively treats sialorrhea. Myoepithelial cells (MECs) are essential for salivary secretion. The role of MECs in BoNT/A-inhibited salivary secretion, and its underlying mechanisms remain unknown.
MATERIALS AND METHODS
BoNT/A was injected into rat submandibular glands (SMGs). At 1, 2, 4, 8, and 12 weeks postinjection, salivary flow rate of SMGs was measured. Electron microscopy, immunohistochemistry, immunofluorescence, and Western blot analysis were used to detect morphological and functional changes in MECs and chemical denervation in SMGs.
RESULTS
BoNT/A temporarily decreased salivary secretion in rat SMGs and this inhibitory effect lasted 4 weeks. During the inhibitory period, MECs atrophied and expressed reduced α-smooth muscle actin (α-SMA), vimentin, and phosphorylated myosin light chain 2 (p-MLC2), suggesting that BoNT/A attenuated MEC contractility. Furthermore, BoNT/A cleaved synaptosome-associated protein 25 (SNAP-25) and decreased the expression and activity of acetylcholinesterase (AChE), indicating that BoNT/A-induced chemical parasympathetic denervation of SMGs by cleaving SNAP-25.
CONCLUSIONS
BoNT/A temporarily caused MEC atrophy and decreased MEC contractility in rat SMGs, which contributed to reversible inhibition of salivary secretion. The underlying mechanisms involved temporary parasympathetic denervation caused by SNAP-25 cleavage. These findings provide new insights into the mechanisms of BoNT/A-inhibited salivary secretion.
Topics: Animals; Botulinum Toxins, Type A; Submandibular Gland; Synaptosomal-Associated Protein 25; Rats; Epithelial Cells; Male; Actins; Rats, Sprague-Dawley; Myosin Light Chains; Vimentin; Acetylcholinesterase; Saliva; Salivation; Atrophy
PubMed: 36971615
DOI: 10.1111/odi.14576 -
NPJ Breast Cancer Mar 2023Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive breast cancer. Virtually all women with DCIS are treated, despite evidence suggesting up to half...
Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive breast cancer. Virtually all women with DCIS are treated, despite evidence suggesting up to half would remain with stable, non-threatening, disease. Overtreatment thus presents a pressing issue in DCIS management. To understand the role of the normally tumour suppressive myoepithelial cell in disease progression we present a 3D in vitro model incorporating both luminal and myoepithelial cells in physiomimetic conditions. We demonstrate that DCIS-associated myoepithelial cells promote striking myoepithelial-led invasion of luminal cells, mediated by the collagenase MMP13 through a non-canonical TGFβ - EP300 pathway. In vivo, MMP13 expression is associated with stromal invasion in a murine model of DCIS progression and is elevated in myoepithelial cells of clinical high-grade DCIS cases. Our data identify a key role for myoepithelial-derived MMP13 in facilitating DCIS progression and point the way towards a robust marker for risk stratification in DCIS patients.
PubMed: 36864079
DOI: 10.1038/s41523-023-00513-6