The Network of Epithelial-mesenchymal transition: potential new targets for tumor resistance

PubMed Central

Nantajit, Danupon; Lin, Dong; Li, Jian Jian

2014-01-01

Purpose In multiple cell metazoans, the ability of polarized epithelial cells to convert to motile mesenchymal cells in order to relocate to another location is governed by a unique process termed epithelial-mesenchymal transition (EMT). While being an essential process of cellular plasticity for normal tissue and organ developments, EMT is found to be involved in an array of malignant phenotypes of tumor cells including proliferation and invasion, angiogenesis, stemness of cancer cells and resistance to chemo-radiotherapy. Although EMT is being extensively studied and demonstrated to play a key role in tumor metastasis and in sustaining tumor hallmarks, there is a lack of clear picture of the overall EMT signaling network, wavering the potential clinical trials targeting EMT. Methods In this review, we highlight the potential key therapeutic targets of EMT linked with tumor aggressiveness, hypoxia, angiogenesis and cancer stem cells, emphasizing on an emerging EMT-associated NF-κB/HER2/STAT3 pathway in radioresistance of breast cancer stem cells. Results Further definition of cancer stem cell repopulation due to EMT-controlled tumor microenvironment will help to understand how tumors exploit the EMT mechanisms for their survival and expansion advantages. Conclusions The knowledge of EMT will offer more effective targets in clinical trials to treat therapy-resistant metastatic lesions. PMID:25270087

Epithelial cell adhesion molecule aptamer functionalized PLGA-lecithin-curcumin-PEG nanoparticles for targeted drug delivery to human colorectal adenocarcinoma cells.

PubMed

Li, Lei; Xiang, Dongxi; Shigdar, Sarah; Yang, Wenrong; Li, Qiong; Lin, Jia; Liu, Kexin; Duan, Wei

2014-01-01

To improve the efficacy of drug delivery, active targeted nanotechnology-based drug delivery systems are gaining considerable attention as they have the potential to reduce side effects, minimize toxicity, and improve efficacy of anticancer treatment. In this work CUR-NPs (curcumin-loaded lipid-polymer-lecithin hybrid nanoparticles) were synthesized and functionalized with ribonucleic acid (RNA) Aptamers (Apts) against epithelial cell adhesion molecule (EpCAM) for targeted delivery to colorectal adenocarcinoma cells. These CUR-encapsulated bioconjugates (Apt-CUR-NPs) were characterized for particle size, zeta potential, drug encapsulation, stability, and release. The in vitro specific cell binding, cellular uptake, and cytotoxicity of Apt-CUR-NPs were also studied. The Apt-CUR-NP bioconjugates exhibited increased binding to HT29 colon cancer cells and enhancement in cellular uptake when compared to CUR-NPs functionalized with a control Apt (P<0.01). Furthermore, a substantial improvement in cytotoxicity was achieved toward HT29 cells with Apt-CUR-NP bioconjugates. The encapsulation of CUR in Apt-CUR-NPs resulted in the increased bioavailability of delivered CUR over a period of 24 hours compared to that of free CUR in vivo. These results show that the EpCAM Apt-functionalized CUR-NPs enhance the targeting and drug delivery of CUR to colorectal cancer cells. Further development of CUR-encapsulated, nanosized carriers will lead to improved targeted delivery of novel chemotherapeutic agents to colorectal cancer cells.

Epithelial stem cells are formed by small-particles released from particle-producing cells

PubMed Central

Kong, Wuyi; Zhu, Xiao Ping; Han, Xiu Juan; Nuo, Mu; Wang, Hong

2017-01-01

Recent spatiotemporal report demonstrated that epidermal stem cells have equal potential to divide or differentiate, with no asymmetric cell division observed. Therefore, how epithelial stem cells maintain lifelong stem-cell support still needs to be elucidated. In mouse blood and bone marrow, we found a group of large cells stained strongly for eosin and containing coiled-tubing-like structures. Many were tightly attached to each other to form large cellular clumps. After sectioning, these large cell-clumps were composed of not cells but numerous small particles, however with few small “naked” nuclei. The small particles were about 2 to 3 μm in diameter and stained dense red for eosin, so they may be rich in proteins. Besides the clumps composed of small particles, we identified clumps formed by fusion of the small particles and clumps of newly formed nucleated cells. These observations suggest that these small particles further fused and underwent cellularization. E-cadherin was expressed in particle-fusion areas, some “naked” nuclei and the newly formed nucleated cells, which suggests that these particles can form epithelial cells via fusion and nuclear remodeling. In addition, we observed similar-particle fusion before epithelial cellularization in mouse kidney ducts after kidney ischemia, which suggests that these particles can be released in the blood and carried to the target tissues for epithelial-cell regeneration. Oct4 and E-cadherin expressed in the cytoplasmic areas in cells that were rich in protein and mainly located in the center of the cellular clumps, suggesting that these newly formed cells have become tissue-specific epithelial stem cells. Our data provide evidence that these large particle-producing cells are the origin of epithelial stem cells. The epithelial stem cells are newly formed by particle fusion. PMID:28253358

Amphiregulin suppresses epithelial cell apoptosis in lipopolysaccharide-induced lung injury in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogata-Suetsugu, Saiko; Yanagihara, Toyoshi; Hamada, Naoki

Background and objective: As a member of the epidermal growth factor family, amphiregulin contributes to the regulation of cell proliferation. Amphiregulin was reported to be upregulated in damaged lung tissues in patients with chronic obstructive pulmonary disease and asthma and in lung epithelial cells in a ventilator-associated lung injury model. In this study, we investigated the effect of amphiregulin on lipopolysaccharide (LPS)-induced acute lung injury in mice. Methods: Acute lung injury was induced by intranasal instillation of LPS in female C57BL/6 mice, and the mice were given intraperitoneal injections of recombinant amphiregulin or phosphate-buffered saline 6 and 0.5 h before andmore » 3 h after LPS instillation. The effect of amphiregulin on apoptosis and apoptotic pathways in a murine lung alveolar type II epithelial cell line (LA-4 cells) were examined using flow cytometry and western blotting, respectively. Results: Recombinant amphiregulin suppressed epithelial cell apoptosis in LPS-induced lung injury in mice. Western blotting revealed that amphiregulin suppressed epithelial cell apoptosis by inhibiting caspase-8 activity. Conclusion: Amphiregulin signaling may be a therapeutic target for LPS-induced lung injury treatment through its prevention of epithelial cell apoptosis. - Highlights: • Amphiregulin suppresses epithelial cell apoptosis in LPS-induced lung injury in mice. • The mechanism relies on inhibiting caspase-8 activity. • Amphiregulin signaling may be a therapeutic target for LPS-induced lung injury.« less

Role of epithelial cells in idiopathic pulmonary fibrosis: from innocent targets to serial killers.

PubMed

Selman, Moisés; Pardo, Annie

2006-06-01

Idiopathic pulmonary fibrosis (IPF), a progressive and relentless lung scarring of unknown etiology, has been recognized as the most lethal interstitial lung disease. Despite the growing interest in IPF, the precise molecular mechanisms underlying the development of fibrosis and leading to the irreversible destruction of the lung are still unknown. Recently, it has been proposed that IPF, instead of being a chronic inflammatory disorder, results from multiple cycles of epithelial cell injury and activation. In turn, active alveolar epithelial cells provoke the migration, proliferation, and activation of mesenchymal cells with the formation of fibroblastic/myofibroblastic foci and the exaggerated accumulation of extracellular matrix, mirroring abnormal wound repair. In this article, some characteristics of the alveolar epithelium are briefly outlined, and the fibrogenic mechanisms specifically operated by active abnormal epithelial cells are examined.

Epithelial cell kinase-B61: an autocrine loop modulating intestinal epithelial migration and barrier function.

PubMed

Rosenberg, I M; Göke, M; Kanai, M; Reinecker, H C; Podolsky, D K

1997-10-01

Epithelial cell kinase (Eck) is a member of a large family of receptor tyrosine kinases whose functions remain largely unknown. Expression and regulation of Eck and its cognate ligand B61 were analyzed in the human colonic adenocarcinoma cell line Caco-2. Immunocytochemical staining demonstrated coexpression of Eck and B61 in the same cells, suggestive of an autocrine loop. Eck levels were maximal in preconfluent cells. In contrast, B61 levels were barely detectable in preconfluent cells and increased progressively after the cells reached confluence. Caco-2 cells cultured in the presence of added B61 showed a significant reduction in the levels of dipeptidyl peptidase and sucrase-isomaltase mRNA, markers of Caco-2 cell differentiation. Cytokines interleukin-1beta (IL-1beta), basic fibroblast growth factor, IL-2, epidermal growth factor, and transforming growth factor-beta modulated steady-state levels of Eck and B61 mRNA and regulated Eck activation as assessed by tyrosine phosphorylation. Functionally, stimulation of Eck by B61 resulted in increased proliferation, enhanced barrier function, and enhanced restitution of injured epithelial monolayers. These results suggest that the Eck-B61 interaction, a target of regulatory peptides, plays a role in intestinal epithelial cell development, migration, and barrier function, contributing to homeostasis and preservation of continuity of the epithelial barrier.

Targeting MMP-13 in bronchial epithelial repair.

PubMed

Howell, Christopher; Smith, James R; Shute, Janis K

2018-06-20

Viral infection of the bronchial epithelium disrupts the barrier properties of the epithelium in healthy individuals and those with lung disease. Repair of the bronchial epithelium is dependent of the formation of a provisional fibrin matrix and migration of epithelial cells to cover denuded areas, followed by proliferation and differentiation. The objective was to test the hypothesis that poly I:C, a model of viral infection, limits epithelial repair through the stimulated release of matrix metalloproteinase-13 (MMP-13). Confluent layers of cultured normal human primary bronchial epithelial cells (NHBE) and SV-40 virus transformed 16HBE14o- bronchial epithelial cells were mechanically wounded, and video microscopy used to measure the rate of wound closure over 2 hours, in the absence and presence of poly I:C (1-20 μg/ml). MMP-13, tissue factor and endothelin release were measured by ELISA. The effect of inhibitors of MMP-13 activity and expression and a non-specific endothelin receptor antagonist, bosentan, on the rate of epithelial repair was investigated RESULTS: Poly I:C limited the rate of epithelial repair, and NHBE were significantly more sensitive to poly I:C effects than 16HBE14o- cells. NHBE, but not 16HBE14o-, released MMP-13 in response to poly I:C. Inhibitors of MMP-13 activity (WAY 170523) and expression (dimethyl fumarate) significantly enhanced the rate of repair. Bosentan enhanced the rate of bronchial epithelial repair by a mechanism that was independent of MMP-13. Bronchial epithelial repair is limited by endothelin and by MMP-13, a protease that degrades coagulation factors, such as fibrinogen, and matrix proteins essential for epithelial repair. Further studies with primary cells from patients are needed to confirm whether repurposing bosentan and inhibitors of MMP-13 expression or activity, for inhalation may be a useful therapeutic strategy in diseases where repeated cycles of epithelial injury and repair occur, such as asthma and COPD. This

Epithelial cell adhesion molecule aptamer functionalized PLGA-lecithin-curcumin-PEG nanoparticles for targeted drug delivery to human colorectal adenocarcinoma cells

PubMed Central

Li, Lei; Xiang, Dongxi; Shigdar, Sarah; Yang, Wenrong; Li, Qiong; Lin, Jia; Liu, Kexin; Duan, Wei

2014-01-01

To improve the efficacy of drug delivery, active targeted nanotechnology-based drug delivery systems are gaining considerable attention as they have the potential to reduce side effects, minimize toxicity, and improve efficacy of anticancer treatment. In this work CUR-NPs (curcumin-loaded lipid-polymer-lecithin hybrid nanoparticles) were synthesized and functionalized with ribonucleic acid (RNA) Aptamers (Apts) against epithelial cell adhesion molecule (EpCAM) for targeted delivery to colorectal adenocarcinoma cells. These CUR-encapsulated bioconjugates (Apt-CUR-NPs) were characterized for particle size, zeta potential, drug encapsulation, stability, and release. The in vitro specific cell binding, cellular uptake, and cytotoxicity of Apt-CUR-NPs were also studied. The Apt-CUR-NP bioconjugates exhibited increased binding to HT29 colon cancer cells and enhancement in cellular uptake when compared to CUR-NPs functionalized with a control Apt (P<0.01). Furthermore, a substantial improvement in cytotoxicity was achieved toward HT29 cells with Apt-CUR-NP bioconjugates. The encapsulation of CUR in Apt-CUR-NPs resulted in the increased bioavailability of delivered CUR over a period of 24 hours compared to that of free CUR in vivo. These results show that the EpCAM Apt-functionalized CUR-NPs enhance the targeting and drug delivery of CUR to colorectal cancer cells. Further development of CUR-encapsulated, nanosized carriers will lead to improved targeted delivery of novel chemotherapeutic agents to colorectal cancer cells. PMID:24591829

Fisetin Inhibits Human Melanoma Cell Invasion through Promotion of Mesenchymal to Epithelial Transition and by Targeting MAPK and NFκB Signaling Pathways

PubMed Central

Pal, Harish Chandra; Sharma, Samriti; Strickland, Leah Ray; Katiyar, Santosh K.; Ballestas, Mary E.; Athar, Mohammad; Elmets, Craig A.; Afaq, Farrukh

2014-01-01

Malignant melanoma is responsible for approximately 75% of skin cancer-related deaths. BRAF plays an important role in regulating the mitogen-activated protein kinase (MAPK) signaling cascade in melanoma with activating mutations in the serine/threonine kinase BRAF occurring in 60–70% of malignant melanomas. The BRAF-MEK-ERK (MAPK) pathway is a key regulator of melanoma cell invasion. In addition, activation of NFκB via the MAPK pathway is regulated through MEK-induced activation of IKK. These pathways are potential targets for prevention and treatment of melanoma. In this study, we investigated the effect of fisetin, a phytochemical present in fruits and vegetables, on melanoma cell invasion and epithelial-mesenchymal transition, and delineated the underlying molecular mechanism. Treatment of multiple human malignant melanoma cell lines with fisetin (5–20 µM) resulted in inhibition of cell invasion. BRAF mutated melanoma cells were more sensitive to fisetin treatment, and this was associated with a decrease in the phosphorylation of MEK1/2 and ERK1/2. In addition, fisetin inhibited the activation of IKK leading to a reduction in the activation of the NFκB signaling pathway. Treatment of cells with an inhibitor of MEK1/2 (PD98059) or of NFκB (caffeic acid phenethyl ester) also reduced melanoma cell invasion. Furthermore, treatment of fisetin promoted mesenchymal to epithelial transition in melanoma cells, which was associated with a decrease in mesenchymal markers (N-cadherin, vimentin, snail and fibronectin) and an increase in epithelial markers (E-cadherin and desmoglein). Employing three dimensional skin equivalents consisting of A375 cells admixed with normal human keratinocytes embedded onto a collagen-constricted fibroblast matrix, we found that treatment of fisetin reduced the invasive potential of melanoma cells into the dermis and increased the expression of E-cadherin with a concomitant decrease in vimentin. These results indicate that fisetin

Interaction of chitin/chitosan with salivary and other epithelial cells-An overview.

PubMed

Patil, Sharvari Vijaykumar; Nanduri, Lalitha S Y

2017-11-01

Chitin and its deacetylated form, chitosan, have been widely used for tissue engineering of both epithelial and mesenchymal tissues. Epithelial cells characterised by their sheet-like tight cellular arrangement and polarised nature, constitute a major component in various organs and play a variety of roles including protection, secretion and maintenance of tissue homeostasis. Regeneration of damaged epithelial tissues has been studied using biomaterials such as chitin, chitosan, hyaluronan, gelatin and alginate. Chitin and chitosan are known to promote proliferation of various embryonic and adult epithelial cells. However it is not clearly understood how this activity is achieved or what are the mechanisms involved in the chitin/chitosan driven proliferation of epithelial cells. Mechanistic understanding of influence of chitin/chitosan on epithelial cells will guide us to develop more targeted regenerative scaffold/hydrogel systems. Therefore, current review attempts to elicit a mechanistic insight into how chitin and chitosan interact with salivary, mammary, skin, nasal, lung, intestinal and bladder epithelial cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of doxycycline on epithelial-mesenchymal transition via the p38/Smad pathway in respiratory epithelial cells.

PubMed

Shin, Jae-Min; Kang, Ju-Hyung; Lee, Seoung-Ae; Park, Il-Ho; Lee, Heung-Man

2017-03-01

Doxycycline has antibacterial and anti-inflammatory effects, and it also suppresses collagen biosynthesis. This study aimed to confirm the effects and mechanism of doxycycline on transforming growth factor (TGF) beta 1 induced epithelial-mesenchymal transition and cell migration in A549 and primary nasal epithelial cells. A 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay and phalloidin-fluorescein isothiocyanate staining were used to evaluate cytotoxicity and cellular morphologic changes. Western blot and immunofluorescence staining were used to determine the expression levels of E-cadherin, vimentin, alpha-smooth muscle actin, fibronectin, phosphorylated Smad2/3, and mitogen-activated protein kinases. Scratch and transwell migration assays were used to assess cellular migration ability. Doxycycline (0-10 μg/mL) had no significant cytotoxic effects in A549 and primary nasal epithelial cells. Increased expression of mesenchymal markers, including vimentin, alpha-smooth muscle actin, and fibronectin in TGF beta 1 induced A549 cells were downregulated by doxycycline treatment. In contrast, E-cadherin expression was upregulated in TGF beta 1 induced A549 cells. An in vitro cell migration assay showed that doxycycline also inhibited the ability of TGF beta 1 induced migration. Doxycycline treatment suppressed the activation of Smad2/3 and p38, whereas its inhibitory effects were similar to each element-specific inhibitor in A549 and primary nasal epithelial cells. Doxycycline inhibited TGF beta 1 induced epithelial-to-mesenchymal transition and migration by targeting Smad2/3 and p38 signal pathways in respiratory epithelial cells.

Delivery of ENaC siRNA to epithelial cells mediated by a targeted nanocomplex: a therapeutic strategy for cystic fibrosis.

PubMed

Manunta, Maria D I; Tagalakis, Aristides D; Attwood, Martin; Aldossary, Ahmad M; Barnes, Josephine L; Munye, Mustafa M; Weng, Alexander; McAnulty, Robin J; Hart, Stephen L

2017-04-06

The inhibition of ENaC may have therapeutic potential in CF airways by reducing sodium hyperabsorption, restoring lung epithelial surface fluid levels, airway hydration and mucociliary function. The challenge has been to deliver siRNA to the lung with sufficient efficacy for a sustained therapeutic effect. We have developed a self-assembling nanocomplex formulation for siRNA delivery to the airways that consists of a liposome (DOTMA/DOPE; L), an epithelial targeting peptide (P) and siRNA (R). LPR formulations were assessed for their ability to silence expression of the transcript of the gene encoding the α-subunit of the sodium channel ENaC in cell lines and primary epithelial cells, in submerged cultures or grown in air-liquid interface conditions. LPRs, containing 50 nM or 100 nM siRNA, showed high levels of silencing, particularly in primary airway epithelial cells. When nebulised these nanocomplexes still retained their biophysical properties and transfection efficiencies. The silencing ability was determined at protein level by confocal microscopy and western blotting. In vivo data demonstrated that these nanoparticles had the ability to silence expression of the α-ENaC subunit gene. In conclusion, these findings show that LPRs can modulate the activity of ENaC and this approach might be promising as co-adjuvant therapy for cystic fibrosis.

Expression of microRNA-133 inhibits epithelial-mesenchymal transition in lung cancer cells by directly targeting FOXQ1.

PubMed

Xiao, Bo; Liu, Huazhen; Gu, Zeyun; Ji, Cheng

2016-10-01

MicroRNA (miR) was implicated in the tumorigenesis of many types of cancer, but no study was conducted on the exact role of miR-133 in lung cancer. We have identified miR-133 as a putative regulator of FOXQ1 expression, and investigated the potential involvement of miR-133 in the migration and invasion of lung cancer cells, as well as the underlying molecular mechanism. MiR-133 directly targeted and down-regulated FOXQ1 expression, which in turn reduced TGF-β level. MiR-133 was down-regulated in lung cancer cell lines A549 and HCC827, and its re-expression significantly inhibited the migration and invasion of the lung cancer cells. Further investigation revealed that this inhibition was caused by reversing the epithelial-mesenchymal transition, evidenced by miR-133 induced elevation of epithelial marker E-cadherin, and reduction of mesenchymal marker Vimentin. Our study is the first to identify miR-133 as a biomarker for lung cancer. It functions to down-regulate FOXQ1, and inhibit epithelial-mesenchymal transition, which antagonizes lung cancer tumorigenesis. Therefore our data support the role of miR-133 as a potential molecular therapeutic tool in treating lung cancer. Copyright © 2015 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

ARP2, a novel pro-apoptotic protein expressed in epithelial prostate cancer LNCaP cells and epithelial ovary CHO transformed cells.

PubMed

Mas-Oliva, Jaime; Navarro-Vidal, Enrique; Tapia-Vieyra, Juana Virginia

2014-01-01

Neoplastic epithelial cells generate the most aggressive types of cancers such as those located in the lung, breast, colon, prostate and ovary. During advanced stages of prostate cancer, epithelial cells are associated to the appearance of androgen-independent tumors, an apoptotic-resistant phenotype that ultimately overgrows and promotes metastatic events. We have previously identified and electrophysiologically characterized a novel Ca(2+)-permeable channel activated during apoptosis in the androgen-independent prostate epithelial cancer cell line, LNCaP. In addition, we reported for the first time the cloning and characterization of this channel-like molecule named apoptosis regulated protein 2 (ARP2) associated to a lethal influx of Ca(2+) in Xenopus oocytes. In the present study, LNCaP cells and Chinese hamster ovary cells (CHO cell line) transfected with arp2-cDNA are induced to undergo apoptosis showing an important impact on cell viability and activation of caspases 3 and 7 when compared to serum deprived grown cells and ionomycin treated cells. The subcellular localization of ARP2 in CHO cells undergoing apoptosis was studied using confocal microscopy. While apoptosis progresses, ARP2 initially localized in the peri-nuclear region of cells migrates with time towards the plasma membrane region. Based on the present results and those of our previous studies, the fact that ARP2 constitutes a novel cation channel is supported. Therefore, ARP2 becomes a valuable target to modulate the influx and concentration of calcium in the cytoplasm of epithelial cancer cells showing an apoptotic-resistant phenotype during the onset of an apoptotic event.

Rho GTPases and Regulation of Cell Migration and Polarization in Human Corneal Epithelial Cells

PubMed Central

Hou, Aihua; Toh, Li Xian; Gan, Kah Hui; Lee, Khee Jin Ryan; Manser, Edward; Tong, Louis

2013-01-01

Purpose Epithelial cell migration is required for regeneration of tissues and can be defective in a number of ocular surface diseases. This study aimed to determine the expression pattern of Rho family small G-proteins in human corneal epithelial cells to test their requirement in directional cell migration. Methods Rho family small G-protein expression was assessed by reverse transcription-polymerase chain reaction. Dominant-inhibitory constructs encoding Rho proteins or Rho protein targeting small interfering RNA were transfected into human corneal epithelial large T antigen cells, and wound closure rate were evaluated by scratch wounding assay, and a complementary non-traumatic cell migration assay. Immunofluorescence staining was performed to study cell polarization and to assess Cdc42 downstream effector. Results Cdc42, Chp, Rac1, RhoA, TC10 and TCL were expressed in human corneal epithelial cells. Among them, Cdc42 and TCL were found to significantly affect cell migration in monolayer scratch assays. These results were confirmed through the use of validated siRNAs directed to Cdc42 and TCL. Scramble siRNA transfected cells had high percentage of polarized cells than Cdc42 or TCL siRNA transfected cells at the wound edge. We showed that the Cdc42-specific effector p21-activated kinase 4 localized predominantly to cell-cell junctions in cell monolayers, but failed to translocate to the leading edge in Cdc42 siRNA transfected cells after monolayer wounding. Conclusion Rho proteins expressed in cultured human corneal epithelial cells, and Cdc42, TCL facilitate two-dimensional cell migration in-vitro. Although silencing of Cdc42 and TCL did not noticeably affect the appearance of cell adhesions at the leading edge, the slower migration of these cells indicates both GTP-binding proteins play important roles in promoting cell movement of human corneal epithelial cells. PMID:24130842

Effective silencing of ENaC by siRNA delivered with epithelial-targeted nanocomplexes in human cystic fibrosis cells and in mouse lung.

PubMed

Tagalakis, Aristides D; Munye, Mustafa M; Ivanova, Rositsa; Chen, Hanpeng; Smith, Claire M; Aldossary, Ahmad M; Rosa, Luca Z; Moulding, Dale; Barnes, Josephine L; Kafetzis, Konstantinos N; Jones, Stuart A; Baines, Deborah L; Moss, Guy W J; O'Callaghan, Christopher; McAnulty, Robin J; Hart, Stephen L

2018-05-10

Loss of the cystic fibrosis transmembrane conductance regulator in cystic fibrosis (CF) leads to hyperabsorption of sodium and fluid from the airway due to upregulation of the epithelial sodium channel (ENaC). Thickened mucus and depleted airway surface liquid (ASL) then lead to impaired mucociliary clearance. ENaC regulation is thus a promising target for CF therapy. Our aim was to develop siRNA nanocomplexes that mediate effective silencing of airway epithelial ENaC in vitro and in vivo with functional correction of epithelial ion and fluid transport. We investigated translocation of nanocomplexes through mucus and their transfection efficiency in primary CF epithelial cells grown at air-liquid interface (ALI).Short interfering RNA (SiRNA)-mediated silencing was examined by quantitative RT-PCR and western analysis of ENaC. Transepithelial potential (V t ), short circuit current (I sc ), ASL depth and ciliary beat frequency (CBF) were measured for functional analysis. Inflammation was analysed by histological analysis of normal mouse lung tissue sections. Nanocomplexes translocated more rapidly than siRNA alone through mucus. Transfections of primary CF epithelial cells with nanocomplexes targeting αENaC siRNA, reduced αENaC and βENaC mRNA by 30%. Transfections reduced V t , the amiloride-sensitive I sc and mucus protein concentration while increasing ASL depth and CBF to normal levels. A single dose of siRNA in mouse lung silenced ENaC by approximately 30%, which persisted for at least 7 days. Three doses of siRNA increased silencing to approximately 50%. Nanoparticle-mediated delivery of ENaCsiRNA to ALI cultures corrected aspects of the mucociliary defect in human CF cells and offers effective delivery and silencing in vivo. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Dietary flavonoid tangeretin induces reprogramming of epithelial to mesenchymal transition in prostate cancer cells by targeting the PI3K/Akt/mTOR signaling pathway.

PubMed

Zhu, Wen-Bin; Xiao, Ning; Liu, Xing-Jie

2018-01-01

Tangeretin, a natural polymethoxyflavone present in the peel of citrus fruits is known to exhibit anticancer properties against a variety of carcinomas. Previous experimental evidence suggests that lifestyle and dietary habits affect the risk of prostate cancer to a certain extent. As the effect of tangeretin on prostate cancer is unexplored, the present study investigated the effect of tangeretin on androgen-insensitive PC-3 cells and androgen-sensitive LNCaP cells. Tangeretin reduced the cell viability of PC-3 cells in a dose- and time-dependent manner, with the half-maximal inhibitory concentration (IC 50 ) observed at 75 µM dose following 72 h of incubation, while in LNCaP cells, the IC 50 was identified to be ~65 µM. Expression levels of the mesenchymal proteins including vimentin, cluster of differentiation 44 and Neural cadherin in PC-3 cells were reduced by tangeretin treatment, whereas those of the epithelial proteins, including Epithelial cadherin and cytokeratin-19 were upregulated. Treatment of PC-3 cells also resulted in the downregulation of the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway. Therefore, it may be concluded that tangeretin induces reprogramming of epithelial-mesenchymal transition in PC-3 cells by targeting the PI3K/Akt/mTOR signaling pathway.

Eosinophils Promote Epithelial to Mesenchymal Transition of Bronchial Epithelial Cells

PubMed Central

Toda, Masaaki; Miyake, Yasushi; Matsushima, Yuki; Matsumoto, Takahiro; Boveda-Ruiz, Daniel; Gil-Bernabe, Paloma; Nagao, Mizuho; Sugimoto, Mayumi; Hiraguchi, Yukiko; Tokuda, Reiko; Naito, Masahiro; Takagi, Takehiro; D'Alessandro-Gabazza, Corina N.; Suga, Shigeru; Kobayashi, Tetsu; Fujisawa, Takao; Taguchi, Osamu; Gabazza, Esteban C.

2013-01-01

Eosinophilic inflammation and remodeling of the airways including subepithelial fibrosis and myofibroblast hyperplasia are characteristic pathological findings of bronchial asthma. Epithelial to mesenchymal transition (EMT) plays a critical role in airway remodelling. In this study, we hypothesized that infiltrating eosinophils promote airway remodelling in bronchial asthma. To demonstrate this hypothesis we evaluated the effect of eosinophils on EMT by in vitro and in vivo studies. EMT was assessed in mice that received intra-tracheal instillation of mouse bone marrow derived eosinophils and in human bronchial epithelial cells co-cultured with eosinophils freshly purified from healthy individuals or with eosinophilic leukemia cell lines. Intra-tracheal instillation of eosinophils was associated with enhanced bronchial inflammation and fibrosis and increased lung concentration of growth factors. Mice instilled with eosinophils pre-treated with transforming growth factor(TGF)-β1 siRNA had decreased bronchial wall fibrosis compared to controls. EMT was induced in bronchial epithelial cells co-cultured with human eosinophils and it was associated with increased expression of TGF-β1 and Smad3 phosphorylation in the bronchial epithelial cells. Treatment with anti-TGF-β1 antibody blocked EMT in bronchial epithelial cells. Eosinophils induced EMT in bronchial epithelial cells, suggesting their contribution to the pathogenesis of airway remodelling. PMID:23700468

Targeting epithelial-mesenchymal plasticity in cancer: clinical and preclinical advances in therapy and monitoring.

PubMed

Bhatia, Sugandha; Monkman, James; Toh, Alan Kie Leong; Nagaraj, Shivashankar H; Thompson, Erik W

2017-09-20

The concept of epithelial-mesenchymal plasticity (EMP), which describes the dynamic flux within the spectrum of phenotypic states that invasive carcinoma cells may reside, is being increasingly recognised for its role in cancer progression and therapy resistance. The myriad of events that are able to induce EMP, as well as the more recently characterised control loops, results in dynamic transitions of cancerous epithelial cells to more mesenchymal-like phenotypes through an epithelial-mesenchymal transition (EMT), as well as the reverse transition from mesenchymal phenotypes to an epithelial one. The significance of EMP, in its ability to drive local invasion, generate cancer stem cells and facilitate metastasis by the dissemination of circulating tumour cells (CTCs), highlights its importance as a targetable programme to combat cancer morbidity and mortality. The focus of this review is to consolidate the existing knowledge on the strategies currently in development to combat cancer progression via inhibition of specific facets of EMP. The prevalence of relapse due to therapy resistance and metastatic propensity that EMP endows should be considered when designing therapy regimes, and such therapies should synergise with existing chemotherapeutics to benefit efficacy. To further improve upon EMP-targeted therapies, it is imperative to devise monitoring strategies to assess the impact of such treatments on EMP-related phenomenon such as CTC burden, chemosensitivity/-resistance and micrometastasis in patients. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Intestinal epithelial cells as producers but not targets of chronic TNF suffice to cause murine Crohn-like pathology

PubMed Central

Roulis, Manolis; Armaka, Maria; Manoloukos, Menelaos; Apostolaki, Maria; Kollias, George

2011-01-01

TNF plays a crucial role in the pathogenesis of Crohn disease. Dysregulated TNF production in mice that bear the genetic deletion of the TNF AU-rich regulatory elements (ARE) (TnfΔARE/+ mice) results in TNF receptor I (TNFRI)-dependent spontaneous Crohn-like pathology. Current concepts consider intestinal epithelial cell (IEC) responses to TNF to be critical for intestinal pathology, but the potential contribution of IEC-derived TNF in disease pathogenesis has not been addressed. In this study we examined whether IEC are sufficient as cellular targets or sources of TNF in the development of intestinal pathology. Using IEC-specific reactivation of a hypomorphic TnfΔAREneo allele in mice, we show that selective chronic overproduction of TNF by IEC suffices to cause full development of Crohn-like pathology. Epithelial TNF overexpression leads to early activation of the underlying intestinal myofibroblast, a cell type previously identified as a sufficient target of TNF for disease development in the TnfΔARE model. By contrast, restricted TNFRI expression on IEC although sufficient to confer IEC apoptosis after acute exogenous TNF administration, fails to induce pathology following chronic specific targeting of IEC by endogenous TNF in TnfΔARE/+ mice. Our results argue against IEC being early and sufficient responders to chronic TNF-mediated pathogenic signals and suggest that proinflammatory aberrations leading to chronic TNF production by IEC may initiate pathology in Crohn disease. PMID:21402942

Characterization of a continuous feline mammary epithelial cell line susceptible to feline epitheliotropic viruses.

PubMed

Pesavento, Patricia; Liu, Hongwei; Ossiboff, Robert J; Stucker, Karla M; Heymer, Anna; Millon, Lee; Wood, Jason; van der List, Deborah; Parker, John S L

2009-04-01

Mucosal epithelial cells are the primary targets for many common viral pathogens of cats. Viral infection of epithelia can damage or disrupt the epithelial barrier that protects underlying tissues. In vitro cell culture systems are an effective means to study how viruses infect and disrupt epithelial barriers, however no true continuous or immortalized feline epithelial cell culture lines are available. A continuous cell culture of feline mammary epithelial cells (FMEC UCD-04-2) that forms tight junctions with high transepithelial electrical resistance (>2000Omegacm(-1)) 3-4 days after reaching confluence was characterized. In addition, it was shown that FMECs are susceptible to infection with feline calicivirus (FCV), feline herpesvirus (FHV-1), feline coronavirus (FeCoV), and feline panleukopenia virus (FPV). These cells will be useful for studies of feline viral disease and for in vitro studies of feline epithelia.

Annexin A9 (ANXA9) biomarker and therapeutic target in epithelial cancer

DOEpatents

Hu, Zhi [El Cerrito, CA; Kuo, Wen-Lin [San Ramon, CA; Neve, Richard M [San Mateo, CA; Gray, Joe W [San Francisco, CA

2012-06-12

Amplification of the ANXA9 gene in human chromosomal region 1q21 in epithelial cancers indicates a likelihood of both in vivo drug resistance and metastasis, and serves as a biomarker indicating these aspects of the disease. ANXA9 can also serve as a therapeutic target. Interfering RNAs (iRNAs) (such as siRNA and miRNA) and shRNA adapted to inhibit ANXA9 expression, when formulated in a therapeutic composition, and delivered to cells of the tumor, function to treat the epithelial cancer.

Hippo/Yap signaling controls epithelial progenitor cell proliferation and differentiation in the embryonic and adult lung

PubMed Central

Lange, Alexander W.; Sridharan, Anusha; Xu, Yan; Stripp, Barry R.; Perl, Anne-Karina; Whitsett, Jeffrey A.

2015-01-01

The Hippo/Yap pathway is a well-conserved signaling cascade that regulates cell proliferation and differentiation to control organ size and stem/progenitor cell behavior. Following airway injury, Yap was dynamically regulated in regenerating airway epithelial cells. To determine the role of Hippo signaling in the lung, the mammalian Hippo kinases, Mst1 and Mst2, were deleted in epithelial cells of the embryonic and mature mouse lung. Mst1/2 deletion in the fetal lung enhanced proliferation and inhibited sacculation and epithelial cell differentiation. The transcriptional inhibition of cell proliferation and activation of differentiation during normal perinatal lung maturation were inversely regulated following embryonic Mst1/2 deletion. Ablation of Mst1/2 from bronchiolar epithelial cells in the adult lung caused airway hyperplasia and altered differentiation. Inhibitory Yap phosphorylation was decreased and Yap nuclear localization and transcriptional targets were increased after Mst1/2 deletion, consistent with canonical Hippo/Yap signaling. YAP potentiated cell proliferation and inhibited differentiation of human bronchial epithelial cells in vitro. Loss of Mst1/2 and expression of YAP regulated transcriptional targets controlling cell proliferation and differentiation, including Ajuba LIM protein. Ajuba was required for the effects of YAP on cell proliferation in vitro. Hippo/Yap signaling regulates Ajuba and controls proliferation and differentiation of lung epithelial progenitor cells. PMID:25480985

Discrete microfluidics for the isolation of circulating tumor cell subpopulations targeting fibroblast activation protein alpha and epithelial cell adhesion molecule.

PubMed

Witek, Małgorzata A; Aufforth, Rachel D; Wang, Hong; Kamande, Joyce W; Jackson, Joshua M; Pullagurla, Swathi R; Hupert, Mateusz L; Usary, Jerry; Wysham, Weiya Z; Hilliard, Dawud; Montgomery, Stephanie; Bae-Jump, Victoria; Carey, Lisa A; Gehrig, Paola A; Milowsky, Matthew I; Perou, Charles M; Soper, John T; Whang, Young E; Yeh, Jen Jen; Martin, George; Soper, Steven A

2017-01-01

Circulating tumor cells consist of phenotypically distinct subpopulations that originate from the tumor microenvironment. We report a circulating tumor cell dual selection assay that uses discrete microfluidics to select circulating tumor cell subpopulations from a single blood sample; circulating tumor cells expressing the established marker epithelial cell adhesion molecule and a new marker, fibroblast activation protein alpha, were evaluated. Both circulating tumor cell subpopulations were detected in metastatic ovarian, colorectal, prostate, breast, and pancreatic cancer patients and 90% of the isolated circulating tumor cells did not co-express both antigens. Clinical sensitivities of 100% showed substantial improvement compared to epithelial cell adhesion molecule selection alone. Owing to high purity (>80%) of the selected circulating tumor cells, molecular analysis of both circulating tumor cell subpopulations was carried out in bulk, including next generation sequencing, mutation analysis, and gene expression. Results suggested fibroblast activation protein alpha and epithelial cell adhesion molecule circulating tumor cells are distinct subpopulations and the use of these in concert can provide information needed to navigate through cancer disease management challenges.

Wnt Signaling in Adult Epithelial Stem Cells and Cancer.

PubMed

Tan, Si Hui; Barker, Nick

2018-01-01

Wnt/β-catenin signaling is integral to the homeostasis and regeneration of many epithelial tissues due to its critical role in adult stem cell regulation. It is also implicated in many epithelial cancers, with mutations in core pathway components frequently present in patient tumors. In this chapter, we discuss the roles of Wnt/β-catenin signaling and Wnt-regulated stem cells in homeostatic, regenerative and cancer contexts of the intestines, stomach, skin, and liver. We also examine the sources of Wnt ligands that form part of the stem cell niche. Despite the diversity in characteristics of various tissue stem cells, the role(s) of Wnt/β-catenin signaling is generally coherent in maintaining stem cell fate and/or promoting proliferation. It is also likely to play similar roles in cancer stem cells, making the pathway a salient therapeutic target for cancer. While promising progress is being made in the field, deeper understanding of the functions and signaling mechanisms of the pathway in individual epithelial tissues will expedite efforts to modulate Wnt/β-catenin signaling in cancer treatment and tissue regeneration. Copyright © 2018 Elsevier Inc. All rights reserved.

Hippo/Yap signaling controls epithelial progenitor cell proliferation and differentiation in the embryonic and adult lung.

PubMed

Lange, Alexander W; Sridharan, Anusha; Xu, Yan; Stripp, Barry R; Perl, Anne-Karina; Whitsett, Jeffrey A

2015-02-01

The Hippo/Yap pathway is a well-conserved signaling cascade that regulates cell proliferation and differentiation to control organ size and stem/progenitor cell behavior. Following airway injury, Yap was dynamically regulated in regenerating airway epithelial cells. To determine the role of Hippo signaling in the lung, the mammalian Hippo kinases, Mst1 and Mst2, were deleted in epithelial cells of the embryonic and mature mouse lung. Mst1/2 deletion in the fetal lung enhanced proliferation and inhibited sacculation and epithelial cell differentiation. The transcriptional inhibition of cell proliferation and activation of differentiation during normal perinatal lung maturation were inversely regulated following embryonic Mst1/2 deletion. Ablation of Mst1/2 from bronchiolar epithelial cells in the adult lung caused airway hyperplasia and altered differentiation. Inhibitory Yap phosphorylation was decreased and Yap nuclear localization and transcriptional targets were increased after Mst1/2 deletion, consistent with canonical Hippo/Yap signaling. YAP potentiated cell proliferation and inhibited differentiation of human bronchial epithelial cells in vitro. Loss of Mst1/2 and expression of YAP regulated transcriptional targets controlling cell proliferation and differentiation, including Ajuba LIM protein. Ajuba was required for the effects of YAP on cell proliferation in vitro. Hippo/Yap signaling regulates Ajuba and controls proliferation and differentiation of lung epithelial progenitor cells. © The Author (2014). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.

Enhancement of cancer stem-like and epithelial−mesenchymal transdifferentiation property in oral epithelial cells with long-term nicotine exposure: Reversal by targeting SNAIL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Cheng-Chia; School of Dentistry, Chung Shan Medical University, Taichung, Taiwan; Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan

Cigarette smoking is one of the major risk factors in the development and further progression of tumorigenesis, including oral squamous cell carcinoma (OSCC). Recent studies suggest that interplay cancer stem-like cells (CSCs) and epithelial−mesenchymal transdifferentiation (EMT) properties are responsible for the tumor maintenance and metastasis in OSCC. The aim of the present study was to investigate the effects of long-term exposure with nicotine, a major component in cigarette, on CSCs and EMT characteristics. The possible reversal regulators were further explored in nicotine-induced CSCs and EMT properties in human oral epithelial (OE) cells. Long-term exposure with nicotine was demonstrated to up-regulatemore » ALDH1 population in normal gingival and primary OSCC OE cells dose-dependently. Moreover, long-term nicotine treatment was found to enhance the self-renewal sphere-forming ability and stemness gene signatures expression and EMT regulators in OE cells. The migration/cell invasiveness/anchorage independent growth and in vivo tumor growth by nude mice xenotransplantation assay was enhanced in long-term nicotine-stimulated OE cells. Knockdown of Snail in long-term nicotine-treated OE cells was found to reduce their CSCs properties. Therapeutic delivery of Si-Snail significantly blocked the xenograft tumorigenesis of long-term nicotine-treated OSCC cells and largely significantly improved the recipient survival. The present study demonstrated that the enrichment of CSCs coupled EMT property in oral epithelial cells induced by nicotine is critical for the development of OSCC tumorigenesis. Targeting Snail might offer a new strategy for the treatment of OSCC patients with smoking habit. -- Highlights: ► Sustained nicotine treatment induced CSCs properties of oral epithelial cells. ► Long-term nicotine treatment enhance EMT properties of oral epithelial cells. ► Long-term nicotine exposure increased tumorigenicity of oral epithelial cells. ► Si

Epithelial-mesenchymal transition abolishes the susceptibility of polarized epithelial cell lines to measles virus.

PubMed

Shirogane, Yuta; Takeda, Makoto; Tahara, Maino; Ikegame, Satoshi; Nakamura, Takanori; Yanagi, Yusuke

2010-07-02

Measles virus (MV), an enveloped negative-strand RNA virus, remains a major cause of morbidity and mortality in developing countries. MV predominantly infects immune cells by using signaling lymphocyte activation molecule (SLAM; also called CD150) as a receptor, but it also infects polarized epithelial cells, forming tight junctions in a SLAM-independent manner. Although the ability of MV to infect polarized epithelial cells is thought to be important for its transmission, the epithelial cell receptor for MV has not been identified. A transcriptional repressor, Snail, induces epithelial-mesenchymal transition (EMT), in which epithelial cells lose epithelial cell phenotypes, such as adherens and tight junctions. In this study, EMT was induced by expressing Snail in a lung adenocarcinoma cell line, II-18, which is highly susceptible to wild-type MV. Snail-expressing II-18 cells lost adherens and tight junctions. Microarray analysis confirmed the induction of EMT in II-18 cells and suggested a novel function of Snail in protein degradation and distribution. Importantly, wild-type MV no longer entered EMT-induced II-18 cells, suggesting that the epithelial cell receptor is down-regulated by the induction of EMT. Other polarized cell lines, NCI-H358 and HT-29, also lost susceptibility to wild-type MV when EMT was induced. However, the complete formation of tight junctions rather reduced MV entry into HT-29 cells. Taken together, these data suggest that the unidentified epithelial cell receptor for MV is involved in the formation of epithelial intercellular junctions.

miRNA-23 regulates high glucose induced epithelial to mesenchymal transition in human mesotheial peritoneal cells by targeting VDR.

PubMed

Yang, Lina; Fan, Yi; Zhang, Xiuli; Ma, Jianfei

2017-11-15

Epithelial-mesenchymal transition(EMT) is the main reason for peritoneal fibrosis and the mechanism underlying peritoneal EMT were extensively studied in recent years. Recent researches showed that miRNAs were so important in the development of organ EMT and fibrosis, the role of microRNAs on peritoneal dialysis have also been studied. In the current study, we investigated microRNA-23(miR-23) expression in high glucose(HG) induced EMT in human mesotheial peritoneal cells(HPMCs). We found that HG promoted EMT, which was characterized by the upregulation of mesenchymal markers α-SMA and FN and downregulation of epithelial marker E-cadherin. The expression miR-23 showed a significant upregulation when treated with HG. Enhanced expression of miR-23 could aggravate HG induced EMT by targeting VDR, inhibition of miR-23 in HPMCs could reverse HG induced EMT by targeting VDR. Furthermore, VDRshRNA exacerbated the EMT process and reversed miR-23 inhibitor-attenuated EMT process in HPMCs. These data manifested that miR-23 played a key role in HG-induced EMT of HPMCs by targeting VDR. Copyright © 2017 Elsevier Inc. All rights reserved.

Overexpression of microRNA-194 suppresses the epithelial-mesenchymal transition in targeting stem cell transcription factor Sox3 in endometrial carcinoma stem cells.

PubMed

Gong, Baolan; Yue, Yan; Wang, Renxiao; Zhang, Yi; Jin, Quanfang; Zhou, Xi

2017-06-01

The epithelial-mesenchymal transition is the key process driving cancer metastasis. MicroRNA-194 inhibits epithelial-mesenchymal transition in several cancers and its downregulation indicates a poor prognosis in human endometrial carcinoma. Self-renewal factor Sox3 induces epithelial-mesenchymal transition at gastrulation and is also involved epithelial-mesenchymal transition in several cancers. We intended to determine the roles of Sox3 in inducing epithelial-mesenchymal transition in endometrial cancer stem cells and the possible role of microRNA-194 in controlling Sox3 expression. Firstly, we found that Sox3 and microRNA-194 expressions were associated with the status of endometrial cancer stem cells in a panel of endometrial carcinoma tissue, the CD133+ cell was higher in tumorsphere than in differentiated cells, and overexpression of microRNA-194 would decrease CD133+ cell expression. Silencing of Sox3 in endometrial cancer stem cell upregulated the epithelial marker E-cadherin, downregulated the mesenchymal marker vimentin, and significantly reduced cell invasion in vitro; overexpression of Sox3 reversed these phenotypes. Furthermore, we discovered that the expression of Sox3 was suppressed by microRNA-194 through direct binding to the Sox3 3'-untranslated region. Ectopic expression of microRNA-194 in endometrial cancer stem cells induced a mesenchymal-epithelial transition by restoring E-cadherin expression, decreasing vimentin expression, and inhibiting cell invasion in vitro. Moreover, overexpression of microRNA-194 inhibited endometrial cancer stem cell invasion or metastasis in vivo by injection of adenovirus microRNA-194. These findings demonstrate the novel mechanism by which Sox3 contributes to endometrial cancer stem cell invasion and suggest that repression of Sox3 by microRNA-194 may have therapeutic potential to suppress endometrial carcinoma metastasis. The cancer stem cell marker, CD133, might be the surface marker of endometrial cancer stem

Characterizing mutagenesis in the hprt gene of rat alveolar epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Driscoll, K.E.; Deyo, L.C.; Howard, B.W.

1995-12-31

A clonal selection assay was developed for mutation in the hypoxanthine-guanine phosphoribosyl transferase (hprt) gene of rat alveolar epithelial cells. Studies were conducted to establish methods for isolation and long-term culture of rat alveolar epithelial cells. When isolated by pronase digestion purified on a Nycodenz gradient and cultured in media containing 7.5% fetal bovine serum (FBS), pituitary extract, EGF, insulin, and IGF-1, rat alveolar epithelial cells could be maintained in culture for several weeks with cell doubling times of 2-4 days. The rat alveolar epithelial cell cultures were exposed in vitro to the mutagens ethylnitrosourea (ENU) and H{sub 2}O{sub 2},more » and mutation in the hprt gene was selected for by culture in the presence of the toxic purine analog, 6-thioguanine (6TG). In vitro exposure to ENU or H{sub 2}O produced a dose-dependent increase in hprt mutation frequency in the alveolar epithelial cells. To determine if the assay system could be used to evaluate mutagenesis in alveolar type II cells after in vivo mutagen or carcinogen exposure, cells were isolated from rats treated previously with ENU or {alpha}-quartz. A significant increase in hprt mutation frequency was detected in alveolar epithelial cells obtained from rats exposed to ENU or {alpha}-quartz; the latter observation is the first demonstration that crystalline silica exposure is mutagenic in vivo. In summary, these studies show that rat alveolar epithelial cells isolated by pronase digestion and Nycodenz separation techniques and cultured in a defined media can be used in a clonal selection assay for mutation in the hprt gene. This assay demonstrates that ENU and H{sub 2}O{sub 2} in vitro and ENU and {alpha}-quartz in vivo are mutagenic for rat alveolar epithelial cells. This model should be useful for investigating the genotoxic effects of chemical and physical agents on an important lung cell target for neoplastic transformation. 41 refs., 4 figs., 3 tabs.« less

Immunological targeting of tumor cells undergoing an epithelial-mesenchymal transition via a recombinant brachyury-yeast vaccine

PubMed Central

Jales, Alessandra; Huang, Bruce; Fernando, Romaine I.; Hodge, James W.; Ardiani, Andressa; Apelian, David

2013-01-01

The embryonic T-box transcription factor brachyury is aberrantly expressed in a range of human tumors. Previous studies have demonstrated that brachyury is a driver of the epithelial-mesenchymal transition (EMT), a process associated with cancer progression. Brachyury expression in human tumor cells enhances tumor invasiveness in vitro and metastasis in vivo, and induces resistance to various conventional therapeutics including chemotherapy and radiation. These characteristics, and the selective expression of brachyury for a range of human tumor types vs. normal adult tissues, make brachyury an attractive tumor target. Due to its intracellular localization and the “undruggable” character of transcription factors, available options to target brachyury are currently limited. Here we report on the development and characterization of an immunological platform for the efficient targeting of brachyury-positive tumors consisting of a heat-killed, recombinant Saccharomyces cerevisiae (yeast)–brachyury vector-based vaccine (designated as GI-6301) that expresses the full-length human brachyury protein. We demonstrate that human dendritic cells treated with recombinant yeast-brachyury can activate and expand brachyury-specific CD4+ and CD8+ T cells in vitro that, in turn, can effectively lyse human tumor cells expressing the brachyury protein. Vaccination of mice with recombinant yeast-brachyury is also shown here to elicit brachyury-specific CD4+ and CD8+ T-cell responses, and to induce anti-tumor immunity in the absence of toxicity. Based on these results, a Phase I clinical trial of GI-6301 is currently ongoing in patients with advanced tumors; to our knowledge, this is the first vaccine platform aimed at targeting a driver of tumor EMT that has successfully reached the clinical stage. PMID:24125763

Evidence of K+ channel function in epithelial cell migration, proliferation, and repair

PubMed Central

Girault, Alban

2013-01-01

Efficient repair of epithelial tissue, which is frequently exposed to insults, is necessary to maintain its functional integrity. It is therefore necessary to better understand the biological and molecular determinants of tissue regeneration and to develop new strategies to promote epithelial repair. Interestingly, a growing body of evidence indicates that many members of the large and widely expressed family of K+ channels are involved in regulation of cell migration and proliferation, key processes of epithelial repair. First, we briefly summarize the complex mechanisms, including cell migration, proliferation, and differentiation, engaged after epithelial injury. We then present evidence implicating K+ channels in the regulation of these key repair processes. We also describe the mechanisms whereby K+ channels may control epithelial repair processes. In particular, changes in membrane potential, K+ concentration, cell volume, intracellular Ca2+, and signaling pathways following modulation of K+ channel activity, as well as physical interaction of K+ channels with the cytoskeleton or integrins are presented. Finally, we discuss the challenges to efficient, specific, and safe targeting of K+ channels for therapeutic applications to improve epithelial repair in vivo. PMID:24196531

A Nasal Epithelial Receptor for Staphylococcus aureus WTA Governs Adhesion to Epithelial Cells and Modulates Nasal Colonization

PubMed Central

Faulstich, Manuela; Grau, Timo; Severin, Yannik; Unger, Clemens; Hoffmann, Wolfgang H.; Rudel, Thomas; Autenrieth, Ingo B.; Weidenmaier, Christopher

2014-01-01

Nasal colonization is a major risk factor for S. aureus infections. The mechanisms responsible for colonization are still not well understood and involve several factors on the host and the bacterial side. One key factor is the cell wall teichoic acid (WTA) of S. aureus, which governs direct interactions with nasal epithelial surfaces. We report here the first receptor for the cell wall glycopolymer WTA on nasal epithelial cells. In several assay systems this type F-scavenger receptor, termed SREC-I, bound WTA in a charge dependent manner and mediated adhesion to nasal epithelial cells in vitro. The impact of WTA and SREC-I interaction on epithelial adhesion was especially pronounced under shear stress, which resembles the conditions found in the nasal cavity. Most importantly, we demonstrate here a key role of the WTA-receptor interaction in a cotton rat model of nasal colonization. When we inhibited WTA mediated adhesion with a SREC-I antibody, nasal colonization in the animal model was strongly reduced at the early onset of colonization. More importantly, colonization stayed low over an extended period of 6 days. Therefore we propose targeting of this glycopolymer-receptor interaction as a novel strategy to prevent or control S. aureus nasal colonization. PMID:24788600

Curcumin inhibits interferon-γ signaling in colonic epithelial cells

PubMed Central

Midura-Kiela, Monica T.; Radhakrishnan, Vijayababu M.; Larmonier, Claire B.; Laubitz, Daniel; Ghishan, Fayez K.

2012-01-01

Curcumin (diferulolylmethane) is an anti-inflammatory phenolic compound found effective in preclinical models of inflammatory bowel diseases (IBD) and in ulcerative colitis patients. Pharmacokinetics of curcumin and its poor systemic bioavailability suggest that it targets preferentially intestinal epithelial cells. The intestinal epithelium, an essential component of the gut innate defense mechanisms, is profoundly affected by IFN-γ, which can disrupt the epithelial barrier function, prevent epithelial cell migration and wound healing, and prime epithelial cells to express major histocompatibility complex class II (MHC-II) molecules and to serve as nonprofessional antigen-presenting cells. In this report we demonstrate that curcumin inhibits IFN-γ signaling in human and mouse colonocytes. Curcumin inhibited IFN-γ-induced gene transcription, including CII-TA, MHC-II genes (HLA-DRα, HLA-DPα1, HLA-DRβ1), and T cell chemokines (CXCL9, 10, and 11). Acutely, curcumin inhibited Stat1 binding to the GAS cis-element, prevented Stat1 nuclear translocation, and reduced Jak1 phosphorylation and phosphorylation of Stat1 at Tyr701. Longer exposure to curcumin led to endocytic internalization of IFNγRα followed by lysosomal fusion and degradation. In summary, curcumin acts as an IFN-γ signaling inhibitor in colonocytes with biphasic mechanisms of action, a phenomenon that may partially account for the beneficial effects of curcumin in experimental colitis and in human IBD. PMID:22038826

Survival Improvement in Human Retinal Pigment Epithelial Cells via Fas Receptor Targeting by miR-374a.

PubMed

Tasharrofi, Nooshin; Kouhkan, Fatemeh; Soleimani, Masoud; Soheili, Zahra-Sheila; Kabiri, Mahboubeh; Mahmoudi Saber, Mohaddeseh; Dorkoosh, Farid Abedin

2017-12-01

Oxidative conditions of the eye could contribute to retinal cells loss through activating the Fas-L/Fas pathway. This phenomenon is one of the leading causes of some ocular diseases like age-related macular degeneration (AMD). By targeting proteins at their mRNA level, microRNAs (miRNAs) can regulate gene expression and cell function. The aim of the present study is to investigate Fas targeting by miR-374a and find whether it can inhibit Fas-mediated apoptosis in primary human retinal pigment epithelial (RPE) cells under oxidative stress. So, the primary human RPE cells were transfected with pre-miR-374a pLEX construct using polymeric carrier and were exposed to H 2 O 2 (200 μM) as an oxidant agent for induction of Fas expression. Fas expression at mRNA and protein level was evaluated by quantitative real-time PCR and Western blot analysis, respectively. These results revealed that miR-374a could prevent Fas upregulation under oxidative conditions. Moreover, Luciferase activity assay confirmed that Fas could be a direct target of miR-374a. The cell viability studies demonstrated that caspase-3 activity was negligible in miR-374a treated cells compared to the controls. Our data suggest miR-374a is a negative regulator of Fas death receptor which is able to enhance the cell survival and protect RPE cells against oxidative conditions. J. Cell. Biochem. 118: 4854-4861, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Selective targeting of alveolar type II respiratory epithelial cells by anti-surfactant protein-C antibody-conjugated lipoplexes

PubMed Central

Wu, Yun; Ma, Junyu; Woods, Parker S.; Chesarino, Nicholas M.; Liu, Chang; Lee, L. James; Nana-Sinkam, Serge P.; Davis, Ian C.

2015-01-01

Alveolar type II (ATII) respiratory epithelial cells are essential to normal lung function. They may be also central to the pathogenesis of diseases such as acute lung injury, pulmonary fibrosis, and pulmonary adenocarcinoma. Hence, ATII cells are important therapeutic targets. However, effective ATII cell-specific drug delivery in vivo requires carriers of an appropriate size, which can cross the hydrophobic alveolar surfactant film and polar aqueous layer overlying ATII cells, and be taken up without inducing ATII cell dysfunction, pulmonary inflammation, lung damage, or excessive systemic spread and side-effects. We have developed lipoplexes as a versatile nanoparticle carrier system for drug/RNA delivery. To optimize their pulmonary localization and ATII cell specificity, lipoplexes were conjugated to an antibody directed against the ATII cell-specific antigen surfactant protein-C (SP-C) then administered to C57BL/6 mice via the nares. Intranasally-administered, anti-SP-C-conjugated lipoplexes targeted mouse ATII cells with >70% specificity in vivo, were retained within ATII cells for at least 48 hours, and did not accumulate at significant levels in other lung cell types or viscera. 48 hours after treatment with anti-SP-C-conjugated lipoplexes containing the test microRNA miR-486, expression of mature miR-486 was approximately 4-fold higher in ATII cells than whole lung by qRT-PCR, and was undetectable in other viscera. Lipoplexes induced no weight loss, hypoxemia, lung dysfunction, pulmonary edema, or pulmonary inflammation over a 6-day period. These findings indicate that ATII cell-targeted lipoplexes exhibit all the desired characteristics of an effective drug delivery system for treatment of pulmonary diseases that result primarily from ATII cell dysfunction. PMID:25687308

Fiber-Optic SPR Immunosensors Tailored To Target Epithelial Cells through Membrane Receptors.

PubMed

Malachovská, Viera; Ribaut, Clotilde; Voisin, Valérie; Surin, Mathieu; Leclère, Philippe; Wattiez, Ruddy; Caucheteur, Christophe

2015-06-16

We report, for the first time, the use of a surface plasmon resonance (SPR) fiber-optic immunosensor for selective cellular detection through membrane protein targeting. The sensor architecture lies on gold-coated tilted fiber Bragg gratings (Au-coated TFBGs) photoimprinted in the fiber core via a laser technique. TFBGs operate in the near-infrared wavelength range at ∼1550 nm, yielding optical and SPR sensing characteristics that are advantageous for the analyses of cellular bindings and technical compatibility with relatively low-cost telecommunication-grade measurement devices. In this work, we take consider their numerous assets to figure out their ability to selectively detect intact epithelial cells as analytes in cell suspensions in the range of 2-5 × 10(6) cells mL(-1). For this, the probe was first thermally annealed to ensure a strong adhesion of the metallic coating to the fiber surface. Its surface was then functionalized with specific monoclonal antibodies via alkanethiol self-assembled monolayers (SAMs) against extracellular domain of epidermal growth factor receptors (EGFRs) and characterized by peak force tapping atomic force microscopy. A differential diagnosis has been demonstrated between two model systems. The developed immunosensors were able to monitor, in real time, the specific attachment of single intact cells in concentrations from 3 × 10(6) cells mL(-1). Such results confirm that the developed probe fits the lab-on-fiber technology and has the potential to be used as a disposable device for in situ and real-time clinical diagnosis.

Bioactive interleukin-1alpha is cytolytically released from Candida albicans-infected oral epithelial cells.

PubMed

Dongari-Bagtzoglou, A; Kashleva, H; Villar, C Cunha

2004-12-01

Oral epithelial cells are primary targets of Candida albicans in the oropharynx and may regulate the inflammatory host response to this pathogen. This investigation studied the mechanisms underlying interleukin-1alpha (IL-1alpha) release by oral epithelial cells and the role of IL-1alpha in regulating the mucosal inflammatory response to C. albicans. Infected oral epithelial cells released processed IL-1alpha protein in culture supernatants. The IL-1alpha generated was stored intracellularly and was released upon cell lysis. This was further supported by the fact that different C. albicans strains induced variable IL-1alpha release, depending on their cytolytic activity. IL-1alpha from C. albicans-infected oral epithelial cells upregulated proinflammatory cytokine secretion (IL-8 and GM-CSF) in uninfected oral epithelial or stromal cells. Our studies suggest that production of IL-1alpha, IL-8 and GM-CSF may take place in the oral mucosa in response to lytic infection of epithelial cells with C. albicans. This process can act as an early innate immune surveillance system and may contribute to the clinicopathologic signs of infection in the oral mucosa.

Hedgehog signalling stimulates precursor cell accumulation and impairs epithelial maturation in the murine oesophagus.

PubMed

van Dop, Willemijn A; Rosekrans, Sanne L; Uhmann, Anja; Jaks, Viljar; Offerhaus, G Johan A; van den Bergh Weerman, Marius A; Kasper, Maria; Heijmans, Jarom; Hardwick, James C H; Verspaget, Hein W; Hommes, Daan W; Toftgård, Rune; Hahn, Heidi; van den Brink, Gijs R

2013-03-01

In the intestine Hedgehog (Hh) signalling is directed from epithelium to mesenchyme and negatively regulates epithelial precursor cell fate. The role of Hh signalling in the oesophagus has not been studied in vivo. Here the authors examined the role of Hh signalling in epithelial homeostasis of oesophagus. The authors used transgenic mice in which the Hh receptor Patched1 (Ptch1) could be conditionally inactivated in a body-wide manner and mice in which Gli1 could be induced specifically in the epithelium of the skin and oesophagus. Effects on epithelial homeostasis of the oesophagus were examined using immunohistochemistry, in situ hybridisation, transmission electron microscopy and real-time PCR. Hh signalling was examined in patients with oesophageal squamous cell carcinoma (SCC) by quantitative real-time PCR. Sonic Hh is signalled in an autocrine manner in the basal layer of the oesophagus. Activation of Hh signalling resulted in an expansion of the epithelial precursor cell compartment and failure of epithelial maturation and migration. Levels of Hh targets GLI1, HHIP and PTCH1 were increased in SCC compared with normal tissue from the same patients. Here the authors find that Hh signalling positively regulates the precursor cell compartment in the oesophageal epithelium in an autocrine manner. Since Hh signalling targets precursor cells in the oesophageal epithelium and signalling is increased in SCCs, Hh signalling may be involved in oesophageal SCC formation.

Differential plasma membrane targeting of voltage-dependent calcium channel subunits expressed in a polarized epithelial cell line

PubMed Central

Brice, Nicola L; Dolphin, Annette C

1999-01-01

Voltage-dependent calcium channels (VDCCs) show a highly non-uniform distribution in many cell types, including neurons and other polarized secretory cells. We have examined whether this can be mimicked in a polarized epithelial cell line (Madin-Darby canine kidney), which has been used extensively to study the targeting of proteins. We expressed the VDCC α1A, α1B or α1C subunits either alone or in combination with accessory subunits α2-δ and the different β subunits, and examined their localization immunocytochemically. An α1 subunit was only targeted to the plasma membrane if co-expressed with the accessory subunits. The combination α1C/α2-δ and all β subunits was always localized predominantly to the basolateral membrane. It has been suggested that this is equivalent to somatodendritic targeting in neurons. In contrast, the α1B subunit was expressed at the apical membrane with all the accessory subunit combinations, by 24 h after microinjection. This membrane destination shows some parallels with axonal targeting in neurons. The α1A subunit was consistently observed at the apical membrane in the combinations α1A/α2-δ/β1b or β4. In contrast, when co-expressed with α2-δ/β2a, α1A was clearly targeted to the basolateral membrane. In conclusion, the VDCC α1 subunit appears to be the primary determinant for targeting the VDCC complex, but the β subunit can modify this destination, particularly for α1A. PMID:10066897

Proteinase-activated receptor 4 stimulation-induced epithelial-mesenchymal transition in alveolar epithelial cells

PubMed Central

Ando, Seijitsu; Otani, Hitomi; Yagi, Yasuhiro; Kawai, Kenzo; Araki, Hiromasa; Fukuhara, Shirou; Inagaki, Chiyoko

2007-01-01

Background Proteinase-activated receptors (PARs; PAR1–4) that can be activated by serine proteinases such as thrombin and neutrophil catepsin G are known to contribute to the pathogenesis of various pulmonary diseases including fibrosis. Among these PARs, especially PAR4, a newly identified subtype, is highly expressed in the lung. Here, we examined whether PAR4 stimulation plays a role in the formation of fibrotic response in the lung, through alveolar epithelial-mesenchymal transition (EMT) which contributes to the increase in myofibroblast population. Methods EMT was assessed by measuring the changes in each specific cell markers, E-cadherin for epithelial cell, α-smooth muscle actin (α-SMA) for myofibroblast, using primary cultured mouse alveolar epithelial cells and human lung carcinoma-derived alveolar epithelial cell line (A549 cells). Results Stimulation of PAR with thrombin (1 U/ml) or a synthetic PAR4 agonist peptide (AYPGKF-NH2, 100 μM) for 72 h induced morphological changes from cobblestone-like structure to elongated shape in primary cultured alveolar epithelial cells and A549 cells. In immunocytochemical analyses of these cells, such PAR4 stimulation decreased E-cadherin-like immunoreactivity and increased α-SMA-like immunoreactivity, as observed with a typical EMT-inducer, tumor growth factor-β (TGF-β). Western blot analyses of PAR4-stimulated A549 cells also showed similar changes in expression of these EMT-related marker proteins. Such PAR4-mediated changes were attenuated by inhibitors of epidermal growth factor receptor (EGFR) kinase and Src. PAR4-mediated morphological changes in primary cultured alveolar epithelial cells were reduced in the presence of these inhibitors. PAR4 stimulation increased tyrosine phosphorylated EGFR or tyrosine phosphorylated Src level in A549 cells, and the former response being inhibited by Src inhibitor. Conclusion PAR4 stimulation of alveolar epithelial cells induced epithelial-mesenchymal transition (EMT

Silencing of Kv4.1 potassium channels inhibits cell proliferation of tumorigenic human mammary epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jang, Soo Hwa; Choi, Changsun; Hong, Seong-Geun

2009-06-26

Potassium channel activity has been shown to facilitate cell proliferation in cancer cells. In the present study, the role of Kv4.1 channels in immortal and tumorigenic human mammary epithelial cells was investigated. Kv4.1 protein expression was positively correlated with tumorigenicity. Moreover, transfection with siRNAs targeting Kv4.1 mRNA suppressed proliferation of tumorigenic mammary epithelial cells. Experiments using mRNA isolated from human breast cancer tissues revealed that the level of Kv4.1 mRNA expression varied depending on the stage of the tumor. Kv4.1 protein expression increased during stages T2 and T3 compared to normal tissue. These results demonstrated that Kv4.1 plays a rolemore » in proliferation of tumorigenic human mammary epithelial cells. In addition, elevated Kv4.1 expression may be useful as a diagnostic marker for staging mammary tumors and selective blockers of Kv4.1 may serve to suppress tumor cell proliferation.« less

MicroRNA-219-5p inhibits the proliferation, migration, and invasion of epithelial ovarian cancer cells by targeting the Twist/Wnt/β-catenin signaling pathway.

PubMed

Wei, Chunyan; Zhang, Xi; He, Sai; Liu, Bianli; Han, Hongfang; Sun, Xuejun

2017-12-30

MicroRNAs are emerging as critical regulators in various fundamental biological processes, including tumor progression. MicroRNA-219-5p (miR-219-5p) has been suggested as a novel tumor suppressing miRNA for many types of human cancers. However, the expression and functional significance of miR-219-5p in epithelial ovarian cancer remain poorly understood. In this study, we sought to explore the potential functions of miR-219-5p in epithelial ovarian cancer. Herein, we found that miR-219-5p levels were significantly decreased in epithelial ovarian cancer tissues and cell lines. Further experiments showed that overexpression of miR-219-5p inhibited epithelial ovarian cancer cell proliferation, migration, and invasion, and suppressed the Wnt/β-catenin signaling pathway. By contrast, suppression of miR-219-5p exhibited the opposite effects. Twist was identified as a downstream target of miR-219-5p, and its expression was directly regulated by miR-219-5p. Restoration of Twist expression in miR-219-5p-overexpresing cells significantly reversed the antitumor effects of miR-219-5p. Taken together, our results revealed a tumor suppressive role for miR-219-5p in epithelial ovarian cancer that includes suppression of cell proliferation, migration, and invasion through downregulation of the Twist/Wnt/β-catenin signaling pathway. Our study suggests that miR-219-5p may have potential applications in the diagnosis and treatment of epithelial ovarian cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Targeted deletion of c-Met in thymic epithelial cells leads to an autoimmune phenotype

PubMed Central

Su, Min; Hu, Rong; Song, Yinhong; Liu, Yalan; Lai, Laijun

2017-01-01

Hepatocyte growth factor (HGF) and its receptor c-Met signaling have been implicated in regulating various types of cells including epithelial cells. We have previously reported that c-Met is expressed by thymic epithelial cells (TECs), and that in vivo administration of hybrid cytokines containing IL-7 and the beta- or alpha-chain of HGF significantly increase the number of TECs. In order to study the role of c-Met signaling in TECs, we generated conditional knockout (cKO) mice in which c-Met was specifically deleted in TECs using a Foxn1-Cre transgene. We show here that c-Met deficiency in TECs results in age-progressive reduction in TEC number and reduced number of regulatory T cells. Consequently, c-Met TEC cKO mice displayed an autoimmune phenotype. Thus, c-Met signaling in TECs is important for the maintenance of TECs and immune self-tolerance. PMID:29363160

miR-27a controls triacylglycerol synthesis in bovine mammary epithelial cells by targeting peroxisome proliferator-activated receptor gamma.

PubMed

Tang, K Q; Wang, Y N; Zan, L S; Yang, W C

2017-05-01

Growing evidence has revealed that microRNA are central elements in milk fat synthesis in mammary epithelial cells. A negative regulator of adipocyte fat synthesis, miR-27a has been reported to be involved in the regulation of milk fat synthesis in goat mammary epithelial cells; however, the regulatory role of miR-27a in bovine milk fat synthesis remains unclear. In the present study, primary bovine mammary epithelial cells (BMEC) were harvested from mid-lactation cows and cultured in Dulbecco's modified Eagle's medium/F-12 medium with 10% fetal bovine serum, 5 μg/mL of insulin, 1 μg/mL of hydrocortisone, 2 μg/mL of prolactin, 1 μg/mL of progesterone, 100 U/mL of penicillin, and 100 μg/mL of streptomycin. We found that the overexpression of miR-27a significantly suppressed lipid droplet formation and decreased the cellular triacylglycerol (TAG) levels, whereas inhibition of miR-27a resulted in a greater lipid droplet formation and TAG accumulation in BMEC. Meanwhile, overexpression of miR-27a inhibited mRNA expression of peroxisome proliferator-activated receptor gamma (PPARG), CCAAT/enhancer-binding protein beta (C/EBPβ), perilipin 2 (PLIN2), and fatty acid binding protein 3 (FABP3), whereas miR-27a downregulation increased PPARG, C/EBPβ, FABP3, and CCAAT enhancer binding protein alpha (C/EBPα) mRNA expression. Furthermore, Western blot analysis revealed the protein level of PPARG in miR-27a mimic and inhibitor transfection groups to be consistent with the mRNA expression response. Moreover, luciferase reporter assays verified that PPARG was the direct target of miR-27a. In summary, these results indicate that miR-27a has the ability to control TAG synthesis in BMEC via targeting PPARG, suggesting that miR-27a could potentially be used to improve beneficial milk components in dairy cows. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Regulated and constitutive protein targeting can be distinguished by secretory polarity in thyroid epithelial cells

PubMed Central

1991-01-01

We have studied concurrent apical/basolateral and regulated/constitutive secretory targeting in filter-grown thyroid epithelial monolayers in vitro, by following the exocytotic routes of two newly synthesized endogenous secretory proteins, thyroglobulin (Tg) and p500. Tg is a regulated secretory protein as indicated by its acute secretory response to secretagogues. Without stimulation, pulse-labeled Tg exhibits primarily two kinetically distinct routes: less than or equal to 80% is released in an apical secretory phase which is largely complete by 6-10 h, with most of the remaining Tg retained in intracellular storage from which delayed apical discharge is seen. The rapid export observed for most Tg is unlikely to be because of default secretion, since its apical polarity is preserved even during the period (less than or equal to 10 h) when p500 is released basolaterally by a constitutive pathway unresponsive to secretagogues. p500 also exhibits a second, kinetically distinct secretory route: at chase times greater than 10 h, a residual fraction (less than or equal to 8%) of p500 is secreted with an apical preponderance similar to that of Tg. It appears that this fraction of p500 has failed to be excluded from the regulated pathway, which has a predetermined apical polarity. From these data we hypothesize that a targeting hierarchy may exist in thyroid epithelial cells such that initial sorting to the regulated pathway may be a way of insuring apical surface delivery from one of two possible exocytotic routes originating in the immature storage compartment. PMID:1991788

The relevance of human stem cell-derived organoid models for epithelial translational medicine

PubMed Central

Hynds, Robert E.; Giangreco, Adam

2014-01-01

Epithelial organ remodeling is a major contributing factor to worldwide death and disease, costing healthcare systems billions of dollars every year. Despite this, most fundamental epithelial organ research fails to produce new therapies and mortality rates for epithelial organ diseases remain unacceptably high. In large part, this failure in translating basic epithelial research into clinical therapy is due to a lack of relevance in existing preclinical models. To correct this, new models are required that improve preclinical target identification, pharmacological lead validation, and compound optimization. In this review, we discuss the relevance of human stem cell-derived, three-dimensional organoid models for addressing each of these challenges. We highlight the advantages of stem cell-derived organoid models over existing culture systems, discuss recent advances in epithelial tissue-specific organoids, and present a paradigm for using organoid models in human translational medicine. PMID:23203919

Melanin targeting for intracellular drug delivery: Quantification of bound and free drug in retinal pigment epithelial cells.

PubMed

Rimpelä, Anna-Kaisa; Hagström, Marja; Kidron, Heidi; Urtti, Arto

2018-05-31

Melanin binding affects drug distribution and retention in pigmented ocular tissues, thereby affecting drug response, duration of activity and toxicity. Therefore, it is a promising possibility for drug targeting and controlled release in the pigmented cells and tissues. Intracellular unbound drug concentrations determine pharmacological and toxicological actions, but analyses of unbound vs. total drug concentrations in pigmented cells are lacking. We studied intracellular binding and cellular drug uptake in pigmented retinal pigment epithelial cells and in non-pigmented ARPE-19 cells with five model drugs (chloroquine, propranolol, timolol, diclofenac, methotrexate). The unbound drug fractions in pigmented cells were 0.00016-0.73 and in non-pigmented cells 0.017-1.0. Cellular uptake (i.e. distribution ratio Kp), ranged from 1.3 to 6300 in pigmented cells and from 1.0 to 25 in non-pigmented cells. Values for intracellular bioavailability, F ic , were similar in both cells types (although larger variation in pigmented cells). In vitro melanin binding parameters were used to predict intracellular unbound drug fraction and cell uptake. Comparison of predictions with experimental data indicates that other factors (e.g. ion-trapping, lipophilicity-related binding to other cell components) also play a role. Melanin binding is a major factor that leads to cellular uptake and unbound drug fractions of a range of 3-4 orders of magnitude indicating that large reservoirs of melanin bound drug can be generated in the cells. Understanding melanin binding has important implications on retinal drug targeting, efficacy and toxicity. Copyright © 2017. Published by Elsevier B.V.

Targeted Deletion and Lipidomic Analysis Identify Epithelial Cell COX-2 as a Major Driver of Chemically-induced Skin Cancer

PubMed Central

Jiao, Jing; Ishikawa, Tomo-o; Dumlao, Darren S.; Norris, Paul C.; Magyar, Clara E.; Mikulec, Carol; Catapang, Art; Dennis, Edward A.; Fischer, Susan M.; Herschman, Harvey R.

2014-01-01

Pharmacologic and global gene deletion studies demonstrate that cyclooxygenase-2 (PTGS2/COX2) plays a critical role in DMBA/TPA-induced skin tumor induction. While many cell types in the tumor microenvironment express COX-2, the cell types in which COX-2 expression is required for tumor promotion are not clearly established. Here, cell-type specific Cox-2 gene deletion reveals a vital role for skin epithelial cell COX-2 expression in DMBA/TPA tumor induction. In contrast, myeloid Cox-2 gene deletion has no effect on DMBA/TPA tumorigenesis. The infrequent, small tumors that develop on mice with an epithelial cell-specific Cox-2 gene deletion have decreased proliferation and increased cell differentiation properties. Blood vessel density is reduced in tumors with an epithelial cell-specific Cox-2 gene deletion, compared to littermate control tumors, suggesting a reciprocal relationship in tumor progression between COX-2 expressing tumor epithelial cells and microenvironment endothelial cells. Lipidomics analysis of skin and tumors from DMBA/TPA-treated mice suggests that the prostaglandins PGE2 and PGF2α are likely candidates for the epithelial cell COX-2-dependent eicosanoids that mediate tumor progression. This study both illustrates the value of cell-type specific gene deletions in understanding the cellular roles of signal-generating pathways in complex microenvironments and emphasizes the benefit of a systems-based lipidomic analysis approach to identify candidate lipid mediators of biological responses. PMID:25063587

Expression and cytokine regulation of immune recognition elements by normal human biliary epithelial and established liver cell lines in vitro.

PubMed

Cruickshank, S M; Southgate, J; Selby, P J; Trejdosiewicz, L K

1998-10-01

Biliary epithelial cells are targets of immune-mediated attack in conditions such as primary biliary cirrhosis and allograft rejection. This has been attributed to the ability of biliary epithelial cells to express ligands for T cell receptors. We aimed to investigate the expression of immune recognition elements and the effects of pro-inflammatory and anti-inflammatory cytokines on cell surface phenotypes of normal human biliary epithelial cells and established human liver-derived (PLC/PRF/5, HepG2, Hep3B and CC-SW) lines. Cells were cultured in the presence or absence of cytokines for 72 h, and expression of cell surface molecules was assessed by flow cytometry and immunofluorescence. All cell lines expressed MHC class I, ICAM-1 (CD54), LFA-3 (CD58) and EGF receptor, and all but Hep3B expressed Fas/Apo-1 (CD95). Unlike hepatocyte-derived cell lines, biliary epithelial cells and CC-SW expressed CD40 and CD44. As expected, IFNgamma and TNFalpha upregulated expression of ICAM-1, MHC class I and MHC class II, particularly in biliary epithelial cells. TGFbeta downregulated these molecules and downregulated CD95 on biliary epithelial cells, but upregulated LFA-3. The Th2 cytokines had little effect, although IL-4 upregulated CD95 expression on biliary epithelial cells. IFNgamma upregulated CD40 expression on biliary epithelial cells, CC-SW and HepG2. These findings imply that biliary epithelial cells may be capable of interacting with activated T lymphocytes via CD40 and LFA-3, which are thought to be important T cell accessory ligands for T cell activation in a B7-independent manner. Sensitivity to pro-inflammatory cytokines and expression of CD95 may explain why biliary epithelial cells are primary targets for autoimmune attack.

Murine epithelial cells: isolation and culture.

PubMed

Davidson, Donald J; Gray, Michael A; Kilanowski, Fiona M; Tarran, Robert; Randell, Scott H; Sheppard, David N; Argent, Barry E; Dorin, Julia R

2004-08-01

We describe an air-liquid interface primary culture method for murine tracheal epithelial cells on semi-permeable membranes, forming polarized epithelia with a high transepithelial resistance, differentiation to ciliated and secretory cells, and physiologically appropriate expression of key genes and ion channels. We also describe the isolation of primary murine nasal epithelial cells for patch-clamp analysis, generating polarised cells with physiologically appropriate distribution and ion channel expression. These methods enable more physiologically relevant analysis of murine airway epithelial cells in vitro and ex vivo, better utilisation of transgenic mouse models of human pulmonary diseases, and have been approved by the European Working Group on CFTR expression.

RSV-encoded NS2 promotes epithelial cell shedding and distal airway obstruction

PubMed Central

Liesman, Rachael M.; Buchholz, Ursula J.; Luongo, Cindy L.; Yang, Lijuan; Proia, Alan D.; DeVincenzo, John P.; Collins, Peter L.; Pickles, Raymond J.

2014-01-01

Respiratory syncytial virus (RSV) infection is the major cause of bronchiolitis in young children. The factors that contribute to the increased propensity of RSV-induced distal airway disease compared with other commonly encountered respiratory viruses remain unclear. Here, we identified the RSV-encoded nonstructural 2 (NS2) protein as a viral genetic determinant for initiating RSV-induced distal airway obstruction. Infection of human cartilaginous airway epithelium (HAE) and a hamster model of disease with recombinant respiratory viruses revealed that NS2 promotes shedding of infected epithelial cells, resulting in two consequences of virus infection. First, epithelial cell shedding accelerated the reduction of virus titers, presumably by clearing virus-infected cells from airway mucosa. Second, epithelial cells shedding into the narrow-diameter bronchiolar airway lumens resulted in rapid accumulation of detached, pleomorphic epithelial cells, leading to acute distal airway obstruction. Together, these data indicate that RSV infection of the airway epithelium, via the action of NS2, promotes epithelial cell shedding, which not only accelerates viral clearance but also contributes to acute obstruction of the distal airways. Our results identify RSV NS2 as a contributing factor for the enhanced propensity of RSV to cause severe airway disease in young children and suggest NS2 as a potential therapeutic target for reducing the severity of distal airway disease. PMID:24713657

Macrophage phenotypic subtypes diametrically regulate epithelial-mesenchymal plasticity in breast cancer cells.

PubMed

Yang, Min; Ma, Bo; Shao, Hanshuang; Clark, Amanda M; Wells, Alan

2016-07-07

Metastatic progression of breast cancer involves phenotypic plasticity of the carcinoma cells moving between epithelial and mesenchymal behaviors. During metastatic seeding and dormancy, even highly aggressive carcinoma cells take on an E-cadherin-positive epithelial phenotype that is absent from the emergent, lethal metastatic outgrowths. These phenotypes are linked to the metastatic microenvironment, though the specific cells and induction signals are still to be deciphered. Recent evidence suggests that macrophages impact tumor progression, and may alter the balance between cancer cell EMT and MErT in the metastatic microenvironment. Here we explore the role of M1/M2 macrophages in epithelial-mesenchymal plasticity of breast cancer cells by coculturing epithelial and mesenchymal cells lines with macrophages. We found that after polarizing the THP-1 human monocyte cell line, the M1 and M2-types were stable and maintained when co-cultured with breast cancer cells. Surprisingly, M2 macrophages may conferred a growth advantage to the epithelial MCF-7 cells, with these cells being driven to a partial mesenchymal phenotypic as indicated by spindle morphology. Notably, E-cadherin protein expression is significantly decreased in MCF-7 cells co-cultured with M2 macrophages. M0 and M1 macrophages had no effect on the MCF-7 epithelial phenotype. However, the M1 macrophages impacted the highly aggressive mesenchymal-like MDA-MB-231 breast cancer cells to take on a quiescent, epithelial phenotype with re-expression of E-cadherin. The M2 macrophages if anything exacerbated the mesenchymal phenotype of the MDA-MB-231 cells. Our findings demonstrate M2 macrophages might impart outgrowth and M1 macrophages may contribute to dormancy behaviors in metastatic breast cancer cells. Thus EMT and MErT are regulated by selected macrophage phenotype in the liver metastatic microenvironment. These results indicate macrophage could be a potential therapeutic target for limiting death due

Solo, a RhoA-targeting guanine nucleotide exchange factor, is critical for hemidesmosome formation and acinar development in epithelial cells.

PubMed

Fujiwara, Sachiko; Matsui, Tsubasa S; Ohashi, Kazumasa; Deguchi, Shinji; Mizuno, Kensaku

2018-01-01

Cell-substrate adhesions are essential for various physiological processes, including embryonic development and maintenance of organ functions. Hemidesmosomes (HDs) are multiprotein complexes that attach epithelial cells to the basement membrane. Formation and remodeling of HDs are dependent on the surrounding mechanical environment; however, the upstream signaling mechanisms are not well understood. We recently reported that Solo (also known as ARHGEF40), a guanine nucleotide exchange factor targeting RhoA, binds to keratin8/18 (K8/K18) intermediate filaments, and that their interaction is important for force-induced actin and keratin cytoskeletal reorganization. In this study, we show that Solo co-precipitates with an HD protein, β4-integrin. Co-precipitation assays revealed that the central region (amino acids 330-1057) of Solo binds to the C-terminal region (1451-1752) of β4-integrin. Knockdown of Solo significantly suppressed HD formation in MCF10A mammary epithelial cells. Similarly, knockdown of K18 or treatment with Y-27632, a specific inhibitor of Rho-associated kinase (ROCK), suppressed HD formation. As Solo knockdown or Y-27632 treatment is known to disorganize K8/K18 filaments, these results suggest that Solo is involved in HD formation by regulating K8/K18 filament organization via the RhoA-ROCK signaling pathway. We also showed that knockdown of Solo impairs acinar formation in MCF10A cells cultured in 3D Matrigel. In addition, Solo accumulated at the site of traction force generation in 2D-cultured MCF10A cells. Taken together, these results suggest that Solo plays a crucial role in HD formation and acinar development in epithelial cells by regulating mechanical force-induced RhoA activation and keratin filament organization.

Solo, a RhoA-targeting guanine nucleotide exchange factor, is critical for hemidesmosome formation and acinar development in epithelial cells

PubMed Central

Matsui, Tsubasa S.; Ohashi, Kazumasa; Deguchi, Shinji; Mizuno, Kensaku

2018-01-01

Cell-substrate adhesions are essential for various physiological processes, including embryonic development and maintenance of organ functions. Hemidesmosomes (HDs) are multiprotein complexes that attach epithelial cells to the basement membrane. Formation and remodeling of HDs are dependent on the surrounding mechanical environment; however, the upstream signaling mechanisms are not well understood. We recently reported that Solo (also known as ARHGEF40), a guanine nucleotide exchange factor targeting RhoA, binds to keratin8/18 (K8/K18) intermediate filaments, and that their interaction is important for force-induced actin and keratin cytoskeletal reorganization. In this study, we show that Solo co-precipitates with an HD protein, β4-integrin. Co-precipitation assays revealed that the central region (amino acids 330–1057) of Solo binds to the C-terminal region (1451–1752) of β4-integrin. Knockdown of Solo significantly suppressed HD formation in MCF10A mammary epithelial cells. Similarly, knockdown of K18 or treatment with Y-27632, a specific inhibitor of Rho-associated kinase (ROCK), suppressed HD formation. As Solo knockdown or Y-27632 treatment is known to disorganize K8/K18 filaments, these results suggest that Solo is involved in HD formation by regulating K8/K18 filament organization via the RhoA-ROCK signaling pathway. We also showed that knockdown of Solo impairs acinar formation in MCF10A cells cultured in 3D Matrigel. In addition, Solo accumulated at the site of traction force generation in 2D-cultured MCF10A cells. Taken together, these results suggest that Solo plays a crucial role in HD formation and acinar development in epithelial cells by regulating mechanical force-induced RhoA activation and keratin filament organization. PMID:29672603

Administration of Menadione, Vitamin K3, Ameliorates Off-Target Effects on Corneal Epithelial Wound Healing Due to Receptor Tyrosine Kinase Inhibition.

PubMed

Rush, Jamie S; Bingaman, David P; Chaney, Paul G; Wax, Martin B; Ceresa, Brian P

2016-11-01

The antiangiogenic receptor tyrosine kinase inhibitor (RTKi), 3-[(4-bromo-2,6-difluorophenyl)methoxy]-5-[[[[4-(1-pyrrolidinyl) butyl] amino] carbonyl]amino]-4-isothiazolecarboxamide hydrochloride, targets VEGFR2 (half maximal inhibitory concentration [IC50] = 11 nM); however, off-target inhibition of epidermal growth factor receptor (EGFR) occurs at higher concentrations. (IC50 = 5.8 μM). This study was designed to determine the effect of topical RTKi treatment on EGF-mediated corneal epithelial wound healing and to develop new strategies to minimize off-target EGFR inhibition. In vitro corneal epithelial wound healing was measured in response to EGF using a transformed human cell line (hTCEpi cells). In vivo corneal wound healing was assessed using a murine model. In these complementary assays, wound healing was measured in the presence of varying RTKi concentrations. Immunoblot analysis was used to examine EGFR and VEGFR2 phosphorylation and the kinetics of EGFR degradation. An Alamar Blue assay measured VEGFR2-mediated cell biology. Receptor tyrosine kinase inhibitor exposure caused dose-dependent inhibition of EGFR-mediated corneal epithelial wound healing in vitro and in vivo. Nanomolar concentrations of menadione, a vitamin K3 analog, when coadministered with the RTKi, slowed EGFR degradation and ameliorated the inhibitory effects on epithelial wound healing both in vitro and in vivo. Menadione did not alter the RTKi's IC50 against VEGFR2 phosphorylation or its inhibition of VEGF-induced retinal endothelial cell proliferation. An antiangiogenic RTKi exhibited off-target effects on the corneal epithelium that can be minimized by menadione without deleteriously affecting its on-target VEGFR2 blockade. These data indicate that menadione has potential as a topical supplement for individuals suffering from perturbations in corneal epithelial homeostasis, especially as an untoward side effect of kinase inhibitors.

PTP-PEST targets a novel tyrosine site in p120 catenin to control epithelial cell motility and Rho GTPase activity.

PubMed

Espejo, Rosario; Jeng, Yowjiun; Paulucci-Holthauzen, Adriana; Rengifo-Cam, William; Honkus, Krysta; Anastasiadis, Panos Z; Sastry, Sarita K

2014-02-01

Tyrosine phosphorylation is implicated in regulating the adherens junction protein, p120 catenin (p120), however, the mechanisms are not well defined. Here, we show, using substrate trapping, that p120 is a direct target of the protein tyrosine phosphatase, PTP-PEST, in epithelial cells. Stable shRNA knockdown of PTP-PEST in colon carcinoma cells results in an increased cytosolic pool of p120 concomitant with its enhanced tyrosine phosphorylation and decreased association with E-cadherin. Consistent with this, PTP-PEST knockdown cells exhibit increased motility, enhanced Rac1 and decreased RhoA activity on a collagen substrate. Furthermore, p120 localization is enhanced at actin-rich protrusions and lamellipodia and has an increased association with the guanine nucleotide exchange factor, VAV2, and cortactin. Exchange factor activity of VAV2 is enhanced by PTP-PEST knockdown whereas overexpression of a VAV2 C-terminal domain or DH domain mutant blocks cell motility. Analysis of point mutations identified tyrosine 335 in the N-terminal domain of p120 as the site of PTP-PEST dephosphorylation. A Y335F mutant of p120 failed to induce the 'p120 phenotype', interact with VAV2, stimulate cell motility or activate Rac1. Together, these data suggest that PTP-PEST affects epithelial cell motility by controlling the distribution and phosphorylation of p120 and its availability to control Rho GTPase activity.

Inhibition of PTP1B disrupts cell-cell adhesion and induces anoikis in breast epithelial cells.

PubMed

Hilmarsdottir, Bylgja; Briem, Eirikur; Halldorsson, Skarphedinn; Kricker, Jennifer; Ingthorsson, Sævar; Gustafsdottir, Sigrun; Mælandsmo, Gunhild M; Magnusson, Magnus K; Gudjonsson, Thorarinn

2017-05-11

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.

Emodin Inhibits Migration and Invasion of Human Endometrial Stromal Cells by Facilitating the Mesenchymal-Epithelial Transition Through Targeting ILK.

PubMed

Zheng, Qiaomei; Xu, Ying; Lu, Jingjing; Zhao, Jing; Wei, Xuan; Liu, Peishu

2016-11-01

To determine whether emodin facilitates the mesenchymal-epithelial transition (MET) of endometrial stromal cells (ESCs) as well as to explore the mechanism through which emodin favored the MET of ESCs. Cell viability was tested by methyl thiazolyl tetrazolium assay. Cell migration and invasion abilities were detected by transwell assays. Levels of integrin-linked kinase (ILK) and epithelial-mesenchymal transition (EMT)-related proteins were detected by Western blot. Upregulated ILK and increased abilities of migration and invasion were confirmed in the eutopic and ectopic ESCs (EuSCs and EcSCs), especially in the EcSCs. After treated with emodin, the expression of ILK was statistically downregulated in EcSCs, resulting in the MET and decreased migration and invasion abilities of EcSCs. Additionally, silencing of the ILK gene in EcSCs also achieved the above-mentioned effects, which were strengthened by emodin. Furthermore, exogenous expression of ILK in control ESCs (CSCs) resulted in the EMT and increased abilities of migration and invasion of CSCs, which can be abrogated by emodin. Besides, exogenous expression of ILK also abrogated the effects of emodin on CSCs. Emodin inhibits the migration and invasion abilities of human ESCs by facilitating the MET through targeting ILK. © The Author(s) 2016.

The epithelial-mesenchymal transition generates cells with properties of stem cells.

PubMed

Mani, Sendurai A; Guo, Wenjun; Liao, Mai-Jing; Eaton, Elinor Ng; Ayyanan, Ayyakkannu; Zhou, Alicia Y; Brooks, Mary; Reinhard, Ferenc; Zhang, Cheng Cheng; Shipitsin, Michail; Campbell, Lauren L; Polyak, Kornelia; Brisken, Cathrin; Yang, Jing; Weinberg, Robert A

2008-05-16

The epithelial-mesenchymal transition (EMT) is a key developmental program that is often activated during cancer invasion and metastasis. We here report that the induction of an EMT in immortalized human mammary epithelial cells (HMLEs) results in the acquisition of mesenchymal traits and in the expression of stem-cell markers. Furthermore, we show that those cells have an increased ability to form mammospheres, a property associated with mammary epithelial stem cells. Independent of this, stem cell-like cells isolated from HMLE cultures form mammospheres and express markers similar to those of HMLEs that have undergone an EMT. Moreover, stem-like cells isolated either from mouse or human mammary glands or mammary carcinomas express EMT markers. Finally, transformed human mammary epithelial cells that have undergone an EMT form mammospheres, soft agar colonies, and tumors more efficiently. These findings illustrate a direct link between the EMT and the gain of epithelial stem cell properties.

Epithelial-mesenchymal transition can suppress major attributes of human epithelial tumor-initiating cells

PubMed Central

Celià-Terrassa, Toni; Meca-Cortés, Óscar; Mateo, Francesca; Martínez de Paz, Alexia; Rubio, Nuria; Arnal-Estapé, Anna; Ell, Brian J.; Bermudo, Raquel; Díaz, Alba; Guerra-Rebollo, Marta; Lozano, Juan José; Estarás, Conchi; Ulloa, Catalina; ρlvarez-Simón, Daniel; Milà, Jordi; Vilella, Ramón; Paciucci, Rosanna; Martínez-Balbás, Marian; García de Herreros, Antonio; Gomis, Roger R.; Kang, Yibin; Blanco, Jerónimo; Fernández, Pedro L.; Thomson, Timothy M.

2012-01-01

Malignant progression in cancer requires populations of tumor-initiating cells (TICs) endowed with unlimited self renewal, survival under stress, and establishment of distant metastases. Additionally, the acquisition of invasive properties driven by epithelial-mesenchymal transition (EMT) is critical for the evolution of neoplastic cells into fully metastatic populations. Here, we characterize 2 human cellular models derived from prostate and bladder cancer cell lines to better understand the relationship between TIC and EMT programs in local invasiveness and distant metastasis. The model tumor subpopulations that expressed a strong epithelial gene program were enriched in highly metastatic TICs, while a second subpopulation with stable mesenchymal traits was impoverished in TICs. Constitutive overexpression of the transcription factor Snai1 in the epithelial/TIC-enriched populations engaged a mesenchymal gene program and suppressed their self renewal and metastatic phenotypes. Conversely, knockdown of EMT factors in the mesenchymal-like prostate cancer cell subpopulation caused a gain in epithelial features and properties of TICs. Both tumor cell subpopulations cooperated so that the nonmetastatic mesenchymal-like prostate cancer subpopulation enhanced the in vitro invasiveness of the metastatic epithelial subpopulation and, in vivo, promoted the escape of the latter from primary implantation sites and accelerated their metastatic colonization. Our models provide new insights into how dynamic interactions among epithelial, self-renewal, and mesenchymal gene programs determine the plasticity of epithelial TICs. PMID:22505459

miR-122 targets NOD2 to decrease intestinal epithelial cell injury in Crohn’s disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Yu; Wang, Chengxiao; Liu, Ying

2013-08-16

Highlights: •NOD2 is a target gene of miR-122. •miR-122 inhibits LPS-induced apoptosis by suppressing NOD2 in HT-29 cells. •miR-122 reduces the expression of pro-inflammatory cytokines (TNF-α and IFN-γ). •miR-122 promotes the release of anti-inflammatory cytokines (IL-4 and IL-10). •NF-κB signaling pathway is involved in inflammatory response induced by LPS. -- Abstract: Crohn’s disease (CD) is one of the two major types of inflammatory bowel disease (IBD) thought to be caused by genetic and environmental factors. Recently, miR-122 was found to be deregulated in association with CD progression. However, the underlying molecular mechanisms remain unclear. In the present study, the genemore » nucleotide-binding oligomerization domain 2 (NOD2/CARD15), which is strongly associated with susceptibility to CD, was identified as a functional target of miR-122. MiR-122 inhibited LPS-induced apoptosis by suppressing NOD2 in HT-29 cells. NOD2 interaction with LPS initiates signal transduction mechanisms resulting in the activation of nuclear factor κB (NF-κB) and the stimulation of downstream pro-inflammatory events. The activation of NF-κB was inhibited in LPS-stimulated HT-29 cells pretreated with miR-122 precursor or NOD2 shRNA. The expression of the pro-inflammatory cytokines TNF-α and IFN-γ was significantly decreased, whereas therelease of the anti-inflammatory cytokines IL-4 and IL-10 was increased in LPS-stimulated HT-29 cells pretreated with miR-122 precursor, NOD2 shRNA or the NF-κB inhibitor QNZ. Taken together, these results indicate that miR-122 and its target gene NOD2 may play an important role in the injury of intestinal epithelial cells induced by LPS.« less

Primary Airway Epithelial Cell Gene Editing Using CRISPR-Cas9.

PubMed

Everman, Jamie L; Rios, Cydney; Seibold, Max A

2018-01-01

The adaptation of the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR associated endonuclease 9 (CRISPR-Cas9) machinery from prokaryotic organisms has resulted in a gene editing system that is highly versatile, easily constructed, and can be leveraged to generate human cells knocked out (KO) for a specific gene. While standard transfection techniques can be used for the introduction of CRISPR-Cas9 expression cassettes to many cell types, delivery by this method is not efficient in many primary cell types, including primary human airway epithelial cells (AECs). More efficient delivery in AECs can be achieved through lentiviral-mediated transduction, allowing the CRISPR-Cas9 system to be integrated into the genome of the cell, resulting in stable expression of the nuclease machinery and increasing editing rates. In parallel, advancements have been made in the culture, expansion, selection, and differentiation of AECs, which allow the robust generation of a bulk edited AEC population from transduced cells. Applying these methods, we detail here our latest protocol to generate mucociliary epithelial cultures knocked out for a specific gene from donor-isolated primary human basal airway epithelial cells. This protocol includes methods to: (1) design and generate lentivirus which targets a specific gene for KO with CRISPR-Cas9 machinery, (2) efficiently transduce AECs, (3) culture and select for a bulk edited AEC population, (4) molecularly screen AECs for Cas9 cutting and specific sequence edits, and (5) further expand and differentiate edited cells to a mucociliary airway epithelial culture. The AEC knockouts generated using this protocol provide an excellent primary cell model system with which to characterize the function of genes involved in airway dysfunction and disease.

S-carboxymethylcysteine inhibits adherence of Streptococcus pneumoniae to human alveolar epithelial cells.

PubMed

Sumitomo, Tomoko; Nakata, Masanobu; Yamaguchi, Masaya; Terao, Yutaka; Kawabata, Shigetada

2012-01-01

Streptococcus pneumoniae is a major pathogen of respiratory infections that utilizes platelet-activating factor receptor (PAFR) for firm adherence to host cells. The mucolytic agent S-carboxymethylcysteine (S-CMC) has been shown to exert inhibitory effects against infection by several respiratory pathogens including S. pneumoniae in vitro and in vivo. Moreover, clinical studies have implicated the benefits of S-CMC in preventing exacerbation of chronic obstructive pulmonary disease, which is considered to be related to respiratory infections. In this study, to assess whether the potency of S-CMC is attributable to inhibition of pneumococcal adherence to host cells, an alveolar epithelial cell line stimulated with interleukin-1α was used as a model of inflamed epithelial cells. Despite upregulation of PAFR by inflammatory activation, treatment with S-CMC efficiently inhibited pneumococcal adherence to host epithelial cells. In order to gain insight into the inhibitory mechanism, the effects of S-CMC on PAFR expression were also investigated. Following treatment with S-CMC, PAFR expression was reduced at both mRNA and post-transcriptional levels. Interestingly, S-CMC was also effective in inhibiting pneumococcal adherence to cells transfected with PAFR small interfering RNAs. These results indicate S-CMC as a probable inhibitor targeting numerous epithelial receptors that interact with S. pneumoniae.

Deep sequencing of small RNA libraries from human prostate epithelial and stromal cells reveal distinct pattern of microRNAs primarily predicted to target growth factors.

PubMed

Singh, Savita; Zheng, Yun; Jagadeeswaran, Guru; Ebron, Jey Sabith; Sikand, Kavleen; Gupta, Sanjay; Sunker, Ramanjulu; Shukla, Girish C

2016-02-28

Complex epithelial and stromal cell interactions are required during the development and progression of prostate cancer. Regulatory small non-coding microRNAs (miRNAs) participate in the spatiotemporal regulation of messenger RNA (mRNA) and regulation of translation affecting a large number of genes involved in prostate carcinogenesis. In this study, through deep-sequencing of size fractionated small RNA libraries we profiled the miRNAs of prostate epithelial (PrEC) and stromal (PrSC) cells. Over 50 million reads were obtained for PrEC in which 860,468 were unique sequences. Similarly, nearly 76 million reads for PrSC were obtained in which over 1 million were unique reads. Expression of many miRNAs of broadly conserved and poorly conserved miRNA families were identified. Sixteen highly expressed miRNAs with significant change in expression in PrSC than PrEC were further analyzed in silico. ConsensusPathDB showed the target genes of these miRNAs were significantly involved in adherence junction, cell adhesion, EGRF, TGF-β and androgen signaling. Let-7 family of tumor-suppressor miRNAs expression was highly pervasive in both, PrEC and PrSC cells. In addition, we have also identified several miRNAs that are unique to PrEC or PrSC cells and their predicted putative targets are a group of transcription factors. This study provides perspective on the miRNA expression in PrEC and PrSC, and reveals a global trend in miRNA interactome. We conclude that the most abundant miRNAs are potential regulators of development and differentiation of the prostate gland by targeting a set of growth factors. Additionally, high level expression of the most members of let-7 family miRNAs suggests their role in the fine tuning of the growth and proliferation of prostate epithelial and stromal cells. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

β2 adrenergic agonist suppresses eosinophil-induced epithelial-to-mesenchymal transition of bronchial epithelial cells.

PubMed

Kainuma, Keigo; Kobayashi, Tetsu; D'Alessandro-Gabazza, Corina N; Toda, Masaaki; Yasuma, Taro; Nishihama, Kota; Fujimoto, Hajime; Kuwabara, Yu; Hosoki, Koa; Nagao, Mizuho; Fujisawa, Takao; Gabazza, Esteban C

2017-05-02

Epithelial-mesenchymal transition is currently recognized as an important mechanism for the increased number of myofibroblasts in cancer and fibrotic diseases. We have already reported that epithelial-mesenchymal transition is involved in airway remodeling induced by eosinophils. Procaterol is a selective and full β 2 adrenergic agonist that is used as a rescue of asthmatic attack inhaler form and orally as a controller. In this study, we evaluated whether procaterol can suppress epithelial-mesenchymal transition of airway epithelial cells induced by eosinophils. Epithelial-mesenchymal transition was assessed using a co-culture system of human bronchial epithelial cells and primary human eosinophils or an eosinophilic leukemia cell line. Procaterol significantly inhibited co-culture associated morphological changes of bronchial epithelial cells, decreased the expression of vimentin, and increased the expression of E-cadherin compared to control. Butoxamine, a specific β 2 -adrenergic antagonist, significantly blocked changes induced by procaterol. In addition, procaterol inhibited the expression of adhesion molecules induced during the interaction between eosinophils and bronchial epithelial cells, suggesting the involvement of adhesion molecules in the process of epithelial-mesenchymal transition. Forskolin, a cyclic adenosine monophosphate-promoting agent, exhibits similar inhibitory activity of procaterol. Overall, these observations support the beneficial effect of procaterol on airway remodeling frequently associated with chronic obstructive pulmonary diseases.

Role of medullary progenitor cells in epithelial cell migration and proliferation

PubMed Central

Chen, Dong; Chen, Zhiyong; Zhang, Yuning; Park, Chanyoung; Al-Omari, Ahmed

2014-01-01

This study is aimed at characterizing medullary interstitial progenitor cells and to examine their capacity to induce tubular epithelial cell migration and proliferation. We have isolated a progenitor cell side population from a primary medullary interstitial cell line. We show that the medullary progenitor cells (MPCs) express CD24, CD44, CXCR7, CXCR4, nestin, and PAX7. MPCs are CD34 negative, which indicates that they are not bone marrow-derived stem cells. MPCs survive >50 passages, and when grown in epithelial differentiation medium develop phenotypic characteristics of epithelial cells. Inner medulla collecting duct (IMCD3) cells treated with conditioned medium from MPCs show significantly accelerated cell proliferation and migration. Conditioned medium from PGE2-treated MPCs induce tubule formation in IMCD3 cells grown in 3D Matrigel. Moreover, most of the MPCs express the pericyte marker PDGFR-b. Our study shows that the medullary interstitium harbors a side population of progenitor cells that can differentiate to epithelial cells and can stimulate tubular epithelial cell migration and proliferation. The findings of this study suggest that medullary pericyte/progenitor cells may play a critical role in collecting duct cell injury repair. PMID:24808539

Targeted deletion and lipidomic analysis identify epithelial cell COX-2 as a major driver of chemically induced skin cancer.

PubMed

Jiao, Jing; Ishikawa, Tomo-O; Dumlao, Darren S; Norris, Paul C; Magyar, Clara E; Mikulec, Carol; Catapang, Art; Dennis, Edward A; Fischer, Susan M; Herschman, Harvey R

2014-11-01

Pharmacologic and global gene deletion studies demonstrate that cyclooxygenase-2 (PTGS2/COX-2) plays a critical role in DMBA/TPA-induced skin tumor induction. Although many cell types in the tumor microenvironment express COX-2, the cell types in which COX-2 expression is required for tumor promotion are not clearly established. Here, cell type-specific Cox-2 gene deletion reveals a vital role for skin epithelial cell COX-2 expression in DMBA/TPA tumor induction. In contrast, myeloid Cox-2 gene deletion has no effect on DMBA/TPA tumorigenesis. The infrequent, small tumors that develop on mice with an epithelial cell-specific Cox-2 gene deletion have decreased proliferation and increased cell differentiation properties. Blood vessel density is reduced in tumors with an epithelial cell-specific Cox-2 gene deletion, compared with littermate control tumors, suggesting a reciprocal relationship in tumor progression between COX-2-expressing tumor epithelial cells and microenvironment endothelial cells. Lipidomics analysis of skin and tumors from DMBA/TPA-treated mice suggests that the prostaglandins PGE2 and PGF2α are likely candidates for the epithelial cell COX-2-dependent eicosanoids that mediate tumor progression. This study both illustrates the value of cell type-specific gene deletions in understanding the cellular roles of signal-generating pathways in complex microenvironments and emphasizes the benefit of a systems-based lipidomic analysis approach to identify candidate lipid mediators of biologic responses. Cox-2 gene deletion demonstrates that intrinsic COX-2 expression in initiated keratinocytes is a principal driver of skin carcinogenesis; lipidomic analysis identifies likely prostanoid effectors. ©2014 American Association for Cancer Research.

Odontogenic epithelial stem cells: hidden sources.

PubMed

Padma Priya, Sivan; Higuchi, Akon; Abu Fanas, Salem; Pooi Ling, Mok; Kumari Neela, Vasantha; Sunil, P M; Saraswathi, T R; Murugan, Kadarkarai; Alarfaj, Abdullah A; Munusamy, Murugan A; Kumar, Suresh

2015-12-01

The ultimate goal of dental stem cell research is to construct a bioengineered tooth. Tooth formation occurs based on the well-organized reciprocal interaction of epithelial and mesenchymal cells. The dental mesenchymal stem cells are the best explored, but because the human odontogenic epithelium is lost after the completion of enamel formation, studies on these cells are scarce. The successful creation of a bioengineered tooth is achievable only when the odontogenic epithelium is reconstructed to produce a replica of natural enamel. This article discusses the untapped sources of odontogenic epithelial stem cells in humans, such as those present in the active dental lamina in postnatal life, in remnants of dental lamina (the gubernaculum cord), in the epithelial cell rests of Malassez, and in reduced enamel epithelium. The possible uses of these stem cells in regenerative medicine, not just for enamel formation, are discussed.

Cyto-adherence of Mycoplasma mycoides subsp. mycoides to bovine lung epithelial cells.

PubMed

Aye, Racheal; Mwirigi, Martin Kiogora; Frey, Joachim; Pilo, Paola; Jores, Joerg; Naessens, Jan

2015-02-07

Mycoplasma mycoides subsp. mycoides (Mmm) is the causative agent of contagious bovine pleuropneumonia (CBPP), a respiratory disease of cattle, whereas the closely related Mycoplasma mycoides subsp. capri (Mmc) is a goat pathogen. Cyto-adherence is a crucial step in host colonization by mycoplasmas and subsequent pathogenesis. The aim of this study was to investigate the interactions between Mmm and mammalian host cells by establishing a cyto-adherence flow cytometric assay and comparing tissue and species specificity of Mmm and Mmc strains. There were little significant differences in the adherence patterns of eight different Mmm strains to adult bovine lung epithelial cells. However, there was statistically significant variation in binding to different host cells types. Highest binding was observed with lung epithelial cells, intermediate binding with endothelial cells and very low binding with fibroblasts, suggesting the presence of effective adherence of Mmm on cells lining the airways of the lung, which is the target organ for this pathogen, possibly by high expression of a specific receptor. However, binding to bovine fetal lung epithelial cells was comparably low; suggesting that the lack of severe pulmonary disease seen in many infected young calves can be explained by reduced expression of a specific receptor. Mmm bound with high efficiency to adult bovine lung cells and less efficiently to calves or goat lung cells. The data show that cyto-adherence of Mmm is species- and tissue- specific confirming its role in colonization of the target host and subsequent infection and development of CBPP.

Isolation, immortalization, and characterization of a human breast epithelial cell line with stem cell properties

PubMed Central

Gudjonsson, Thorarinn; Villadsen, René; Nielsen, Helga Lind; Rønnov-Jessen, Lone; Bissell, Mina J.; Petersen, Ole William

2002-01-01

The epithelial compartment of the human breast comprises two distinct lineages: the luminal epithelial and the myoepithelial lineage. We have shown previously that a subset of the luminal epithelial cells could convert to myoepithelial cells in culture signifying the possible existence of a progenitor cell. We therefore set out to identify and isolate the putative precursor in the luminal epithelial compartment. Using cell surface markers and immunomagnetic sorting, we isolated two luminal epithelial cell populations from primary cultures of reduction mammoplasties. The major population coexpresses sialomucin (MUC+) and epithelial-specific antigen (ESA+) whereas the minor population has a suprabasal position and expresses epithelial specific antigen but no sialomucin (MUC−/ESA+). Two cell lines were further established by transduction of the E6/E7 genes from human papilloma virus type 16. Both cell lines maintained a luminal epithelial phenotype as evidenced by expression of the tight junction proteins, claudin-1 and occludin, and by generation of a high transepithelial electrical resistance on semipermeable filters. Whereas in clonal cultures, the MUC+/ESA+ epithelial cell line was luminal epithelial restricted in its differentiation repertoire, the suprabasal-derived MUC−/ESA+ epithelial cell line was able to generate itself as well as MUC+/ESA+ epithelial cells and Thy-1+/α-smooth muscle actin+ (ASMA+) myoepithelial cells. The MUC−/ESA+ epithelial cell line further differed from the MUC+/ESA+ epithelial cell line by the expression of keratin K19, a feature of a subpopulation of epithelial cells in terminal duct lobular units in vivo. Within a reconstituted basement membrane, the MUC+/ESA+ epithelial cell line formed acinus-like spheres. In contrast, the MUC−/ESA+ epithelial cell line formed elaborate branching structures resembling uncultured terminal duct lobular units both by morphology and marker expression. Similar structures were obtained by

Interaction of galectin-3 with MUC1 on cell surface promotes EGFR dimerization and activation in human epithelial cancer cells.

PubMed

Piyush, Tushar; Chacko, Anisha R; Sindrewicz, Paulina; Hilkens, John; Rhodes, Jonathan M; Yu, Lu-Gang

2017-11-01

Epidermal growth factor receptor (EGFR) is an important regulator of epithelial cell growth and survival in normal and cancerous tissues and is a principal therapeutic target for cancer treatment. EGFR is associated in epithelial cells with the heavily glycosylated transmembrane mucin protein MUC1, a natural ligand of galectin-3 that is overexpressed in cancer. This study reveals that the expression of cell surface MUC1 is a critical enhancer of EGF-induced EGFR activation in human breast and colon cancer cells. Both the MUC1 extracellular and intracellular domains are involved in EGFR activation but the predominant influence comes from its extracellular domain. Binding of galectin-3 to the MUC1 extracellular domain induces MUC1 cell surface polarization and increases MUC1-EGFR association. This leads to a rapid increase of EGFR homo-/hetero-dimerization and subsequently increased, and also prolonged, EGFR activation and signalling. This effect requires both the galectin-3 C-terminal carbohydrate recognition domain and its N-terminal ligand multi-merization domain. Thus, interaction of galectin-3 with MUC1 on cell surface promotes EGFR dimerization and activation in epithelial cancer cells. As MUC1 and galectin-3 are both commonly overexpressed in most types of epithelial cancers, their interaction and impact on EGFR activation likely makes important contribution to EGFR-associated tumorigenesis and cancer progression and may also influence the effectiveness of EGFR-targeted cancer therapy.

Epithelial-mesenchymal transition in breast epithelial cells treated with cadmium and the role of Snail.

PubMed

Wei, Zhengxi; Shan, Zhongguo; Shaikh, Zahir A

2018-04-01

Epidemiological and experimental studies have implicated cadmium (Cd) with breast cancer. In breast epithelial MCF10A and MDA-MB-231 cells, Cd has been shown to promote cell growth. The present study examined whether Cd also promotes epithelial-mesenchymal transition (EMT), a hallmark of cancer progression. Human breast epithelial cells consisting of non-cancerous MCF10A, non-metastatic HCC 1937 and HCC 38, and metastatic MDA-MB-231 were treated with 1 or 3 μM Cd for 4 weeks. The MCF10A epithelial cells switched to a more mesenchymal-like morphology, which was accompanied by a decrease in the epithelial marker E-cadherin and an increase in the mesenchymal markers N-cadherin and vimentin. In both non-metastatic HCC 1937 and HCC 38 cells, treatment with Cd decreased the epithelial marker claudin-1. In addition, E-cadherin also decreased in the HCC 1937 cells. Even the mesenchymal-like MDA-MB-231 cells exhibited an increase in the mesenchymal marker vimentin. These changes indicated that prolonged treatment with Cd resulted in EMT in both normal and cancer-derived breast epithelial cells. Furthermore, both the MCF10A and MDA-MB-231 cells labeled with Zcad, a dual sensor for tracking EMT, demonstrated a decrease in the epithelial marker E-cadherin and an increase in the mesenchymal marker ZEB-1. Treatment of cells with Cd significantly increased the level of Snail, a transcription factor involved in the regulation of EMT. However, the Cd-induced Snail expression was completely abolished by actinomycin D. Luciferase reporter assay indicated that the expression of Snail was regulated by Cd at the promotor level. Snail was essential for Cd-induced promotion of EMT in the MDA-MB-231 cells, as knockdown of Snail expression blocked Cd-induced cell migration. Together, these results indicate that Cd promotes EMT in breast epithelial cells and does so by modulating the transcription of Snail. Copyright © 2018 Elsevier Inc. All rights reserved.

Effect of Rebamipide, a Novel Antiulcer Agent, on Helicobacter pylori Adhesion to Gastric Epithelial Cells

PubMed Central

Hayashi, Shunji; Sugiyama, Toshiro; Amano, Ken-Ichi; Isogai, Hiroshi; Isogai, Emiko; Aihara, Miki; Kikuchi, Mikio; Asaka, Masahiro; Yokota, Kenji; Oguma, Keiji; Fujii, Nobuhiro; Hirai, Yoshikazu

1998-01-01

Helicobacter pylori is a major etiological agent in gastroduodenal disorders. The adhesion of H. pylori to human gastric epithelial cells is the initial step of H. pylori infection. Inhibition of H. pylori adhesion is thus a therapeutic target in the prevention of H. pylori infection. Experiments were performed to evaluate the effect of rebamipide, a novel antiulcer agent, on H. pylori adhesion to gastric epithelial cells. MKN-28 and MKN-45 cells, derived from human gastric carcinomas, were used as target cells. Ten H. pylori strains isolated from patients with chronic gastritis and gastric ulcer were used in the study. We evaluated the effect of rebamipide on H. pylori adhesion to MKN-28 and MKN-45 cells quantitatively using our previously established enzyme-linked immunosorbent assay. The adhesion of H. pylori to MKN-28 and MKN-45 cells was significantly inhibited by pretreatment of these cells with 100 μg of rebamipide per ml. However, the adhesion was not affected by the pretreatment of H. pylori with rebamipide. On the other hand, the viabilities of H. pylori, MKN-28 cells, and MKN-45 cells were not affected by rebamipide. Our studies suggest that rebamipide inhibits the adhesion of H. pylori to gastric epithelial cells. PMID:9687380

Release of HIV-1 sequestered in the vesicles of oral and genital mucosal epithelial cells by epithelial-lymphocyte interaction

PubMed Central

Yasen, Aizezi; Herrera, Rossana; Rosbe, Kristina

2017-01-01

Oropharyngeal mucosal epithelia of fetuses/neonates/infants and the genital epithelia of adults play a critical role in HIV-1 mother-to-child transmission and sexual transmission of virus, respectively. To study the mechanisms of HIV-1 transmission through mucosal epithelium, we established polarized tonsil, cervical and foreskin epithelial cells. Analysis of HIV-1 transmission through epithelial cells showed that approximately 0.05% of initially inoculated virions transmigrated via epithelium. More than 90% of internalized virions were sequestered in the endosomes of epithelial cells, including multivesicular bodies (MVBs) and vacuoles. Intraepithelial HIV-1 remained infectious for 9 days without viral release. Release of sequestered intraepithelial HIV-1 was induced by the calcium ionophore ionomycin and by cytochalasin D, which increase intracellular calcium and disrupt the cortical actin of epithelial cells, respectively. Cocultivation of epithelial cells containing HIV-1 with activated peripheral blood mononuclear cells and CD4+ T lymphocytes led to the disruption of epithelial cortical actin and spread of virus from epithelial cells to lymphocytes. Treatment of epithelial cells with proinflammatory cytokines tumor necrosis factor-alpha and interferon gamma also induced reorganization of cortical actin and release of virus. Inhibition of MVB formation by small interfering RNA (siRNA)-mediated silencing of its critical protein hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) expression reduced viral sequestration in epithelial cells and its transmission from epithelial cells to lymphocytes by ~60–70%. Furthermore, inhibition of vacuole formation of epithelial cells by siRNA-inactivated rabankyrin-5 expression also significantly reduced HIV-1 sequestration in epithelial cells and spread of virus from epithelial cells to lymphocytes. Interaction of the intercellular adhesion molecule-1 of epithelial cells with the function-associated antigen-1

Targeting Epithelial-Mesenchymal Transition (EMT) to Overcome Drug Resistance in Cancer.

PubMed

Du, Bowen; Shim, Joong Sup

2016-07-22

Epithelial-mesenchymal transition (EMT) is known to play an important role in cancer progression, metastasis and drug resistance. Although there are controversies surrounding the causal relationship between EMT and cancer metastasis, the role of EMT in cancer drug resistance has been increasingly recognized. Numerous EMT-related signaling pathways are involved in drug resistance in cancer cells. Cells undergoing EMT show a feature similar to cancer stem cells (CSCs), such as an increase in drug efflux pumps and anti-apoptotic effects. Therefore, targeting EMT has been considered a novel opportunity to overcome cancer drug resistance. This review describes the mechanism by which EMT contributes to drug resistance in cancer cells and summarizes new advances in research in EMT-associated drug resistance.

Myb permits multilineage airway epithelial cell differentiation

PubMed Central

Pan, Jie-hong; Adair-Kirk, Tracy L.; Patel, Anand C.; Huang, Tao; Yozamp, Nicholas S.; Xu, Jian; Reddy, E. Premkumar; Byers, Derek E.; Pierce, Richard A.; Holtzman, Michael J.; Brody, Steven L.

2014-01-01

The epithelium of the pulmonary airway is specially differentiated to provide defense against environmental insults, but also subject to dysregulated differentiation that results in lung disease. The current paradigm for airway epithelial differentiation is a one-step program whereby a p63+ basal epithelial progenitor cell generates a ciliated or secretory cell lineage, but the cue for this transition and whether there are intermediate steps is poorly defined. Here we identify transcription factor Myb as a key regulator that permits early multilineage differentiation of airway epithelial cells. Myb+ cells were identified as p63− and therefore distinct from basal progenitor cells, but were still negative for markers of differentiation. Myb RNAi treatment of primary-culture airway epithelial cells and Myb gene deletion in mice resulted in a p63− population with failed maturation of Foxj1+ ciliated cells, as well as Scbg1a1+ and Muc5ac+ secretory cells. Consistent with these findings, analysis of whole genome expression of Myb-deficient cells identified Myb-dependent programs for ciliated and secretory cell differentiation. Myb+ cells were rare in human airways but were increased in regions of ciliated cells and mucous cell hyperplasia in samples from subjects with chronic obstructive pulmonary disease. Together, the results show that a p63− Myb+ population of airway epithelial cells represents a distinct intermediate stage of differentiation that is required under normal conditions and may be heightened in airway disease. PMID:25103188

Lysophosphatidic acid signaling through its receptor initiates profibrotic epithelial cell fibroblast communication mediated by epithelial cell derived connective tissue growth factor.

PubMed

Sakai, Norihiko; Chun, Jerold; Duffield, Jeremy S; Lagares, David; Wada, Takashi; Luster, Andrew D; Tager, Andrew M

2017-03-01

The expansion of the fibroblast pool is a critical step in organ fibrosis, but the mechanisms driving expansion remain to be fully clarified. We previously showed that lysophosphatidic acid (LPA) signaling through its receptor LPA 1 expressed on fibroblasts directly induces the recruitment of these cells. Here we tested whether LPA-LPA 1 signaling drives fibroblast proliferation and activation during the development of renal fibrosis. LPA 1 -deficient (LPA 1 -/- ) or -sufficient (LPA 1 +/+ ) mice were crossed to mice with green fluorescent protein expression (GFP) driven by the type I procollagen promoter (Col-GFP) to identify fibroblasts. Unilateral ureteral obstruction-induced increases in renal collagen were significantly, though not completely, attenuated in LPA 1 -/- Col-GFP mice, as were the accumulations of both fibroblasts and myofibroblasts. Connective tissue growth factor was detected mainly in tubular epithelial cells, and its levels were suppressed in LPA 1 -/- Col-GFP mice. LPA-LPA 1 signaling directly induced connective tissue growth factor expression in primary proximal tubular epithelial cells, through a myocardin-related transcription factor-serum response factor pathway. Proximal tubular epithelial cell-derived connective tissue growth factor mediated renal fibroblast proliferation and myofibroblast differentiation. Administration of an inhibitor of myocardin-related transcription factor/serum response factor suppressed obstruction-induced renal fibrosis. Thus, targeting LPA-LPA 1 signaling and/or myocardin-related transcription factor/serum response factor-induced transcription could be promising therapeutic strategies for renal fibrosis. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Documentation of angiotensin II receptors in glomerular epithelial cells

NASA Technical Reports Server (NTRS)

Sharma, M.; Sharma, R.; Greene, A. S.; McCarthy, E. T.; Savin, V. J.; Cowley, A. W. (Principal Investigator)

1998-01-01

Angiotensin II decreases glomerular filtration rate, renal plasma flow, and glomerular capillary hydraulic conductivity. Although angiotensin II receptors have been demonstrated in mesangial cells and proximal tubule cells, the presence of angiotensin II receptors in glomerular epithelial cells has not previously been shown. Previously, we have reported that angiotensin II caused an accumulation of cAMP and a reorganization of the actin cytoskeleton in cultured glomerular epithelial cells. Current studies were conducted to verify the presence of angiotensin II receptors by immunological and non-peptide receptor ligand binding techniques and to ascertain the activation of intracellular signal transduction in glomerular epithelial cells in response to angiotensin II. Confluent monolayer cultures of glomerular epithelial cells were incubated with angiotensin II, with or without losartan and/or PD-123,319 in the medium. Membrane vesicle preparations were obtained by homogenization of washed cells followed by centrifugation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membrane proteins followed by multiscreen immunoblotting was used to determine the presence of angiotensin II receptor type 1 (AT1) or type 2 (AT2). Angiotensin II-mediated signal transduction in glomerular epithelial cells was studied by measuring the levels of cAMP, using radioimmunoassay. Results obtained in these experiments showed the presence of both AT1 and AT2 receptor types in glomerular epithelial cells. Angiotensin II was found to cause an accumulation of cAMP in glomerular epithelial cells, which could be prevented only by simultaneous use of losartan and PD-123,319, antagonists for AT1 and AT2, respectively. The presence of both AT1 and AT2 receptors and an increase in cAMP indicate that glomerular epithelial cells respond to angiotensin II in a manner distinct from that of mesangial cells or proximal tubular epithelial cells. Our results suggest that glomerular epithelial

PTP-PEST targets a novel tyrosine site in p120 catenin to control epithelial cell motility and Rho GTPase activity

PubMed Central

Espejo, Rosario; Jeng, Yowjiun; Paulucci-Holthauzen, Adriana; Rengifo-Cam, William; Honkus, Krysta; Anastasiadis, Panos Z.; Sastry, Sarita K.

2014-01-01

ABSTRACT Tyrosine phosphorylation is implicated in regulating the adherens junction protein, p120 catenin (p120), however, the mechanisms are not well defined. Here, we show, using substrate trapping, that p120 is a direct target of the protein tyrosine phosphatase, PTP-PEST, in epithelial cells. Stable shRNA knockdown of PTP-PEST in colon carcinoma cells results in an increased cytosolic pool of p120 concomitant with its enhanced tyrosine phosphorylation and decreased association with E-cadherin. Consistent with this, PTP-PEST knockdown cells exhibit increased motility, enhanced Rac1 and decreased RhoA activity on a collagen substrate. Furthermore, p120 localization is enhanced at actin-rich protrusions and lamellipodia and has an increased association with the guanine nucleotide exchange factor, VAV2, and cortactin. Exchange factor activity of VAV2 is enhanced by PTP-PEST knockdown whereas overexpression of a VAV2 C-terminal domain or DH domain mutant blocks cell motility. Analysis of point mutations identified tyrosine 335 in the N-terminal domain of p120 as the site of PTP-PEST dephosphorylation. A Y335F mutant of p120 failed to induce the ‘p120 phenotype’, interact with VAV2, stimulate cell motility or activate Rac1. Together, these data suggest that PTP-PEST affects epithelial cell motility by controlling the distribution and phosphorylation of p120 and its availability to control Rho GTPase activity. PMID:24284071

Epithelial Cells in Urine: MedlinePlus Lab Test Information

MedlinePlus

... page: https://medlineplus.gov/labtests/epithelialcellsinurine.html Epithelial Cells in Urine To use the sharing features on ... page, please enable JavaScript. What is an Epithelial Cells in Urine Test? Epithelial cells are a type ...

Immortalized bovine mammary epithelial cells express stem cell markers and differentiate in vitro.

PubMed

Hu, Han; Zheng, Nan; Gao, Haina; Dai, Wenting; Zhang, Yangdong; Li, Songli; Wang, Jiaqi

2016-08-01

The bovine mammary epithelial cell is a secretory cell, and its cell number and secretory activity determine milk production. In this study, we immortalized a bovine mammary epithelial cell line by SV40 large T antigen gene using a retrovirus based on Chinese Holstein primary mammary epithelial cells (CMEC) cultured in vitro. An immortalized bovine mammary epithelial cell line surpassed the 50-passage mark and was designated the CMEC-H. The immortalized mammary epithelial cells grew in close contact with each other and exhibited the typical cobblestone morphology characteristic with obvious boundaries. The telomerase expression of CMEC-H has consistently demonstrated the presence of telomerase activity as an immortalized cell line, but the cell line never induced tumor formation in nude mice. CMEC-H expressed epithelial (cytokeratins CK7, CK8, CK18, and CK19), mesenchymal (vimentin), and stem/progenitor (CD44 and p63) cell markers. The induced expression of milk proteins, αS1 -casein, β-casein, κ-casein, and butyrophilin, indicated that CMEC-H maintained the synthesis function of the mammary epithelial cells. The established immortalized bovine mammary epithelial cell line CMEC-H is capable of self-renewal and differentiation and can serve as a valuable reagent for studying the physiological mechanism of the mammary gland. © 2016 International Federation for Cell Biology.

Silk Film Topography Directs Collective Epithelial Cell Migration

PubMed Central

Rosenblatt, Mark I.

2012-01-01

The following study provides new insight into how surface topography dictates directed collective epithelial cell sheet growth through the guidance of individual cell movement. Collective cell behavior of migrating human corneal limbal-epithelial cell sheets were studied on highly biocompatible flat and micro-patterned silk film surfaces. The silk film edge topography guided the migratory direction of individual cells making up the collective epithelial sheet, which resulted in a 75% increase in total culture elongation. This was due to a 3-fold decrease in cell sheet migration rate efficiency for movement perpendicular to the topography edge. Individual cell migration direction is preferred in the parallel approach to the edge topography where localization of cytoskeletal proteins to the topography’s edge region is reduced, which results in the directed growth of the collective epithelial sheet. Findings indicate customized biomaterial surfaces may be created to direct both the migration rate and direction of tissue epithelialization. PMID:23185573

Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Yang; Pang, Xiaoyan; Dong, Mei

Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesitymore » has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.« less

Targeted overexpression of EZH2 in the mammary gland disrupts ductal morphogenesis and causes epithelial hyperplasia.

PubMed

Li, Xin; Gonzalez, Maria E; Toy, Katherine; Filzen, Tracey; Merajver, Sofia D; Kleer, Celina G

2009-09-01

The Polycomb group protein enhancer of zeste homolog 2 (EZH2), which has roles during development of numerous tissues, is a critical regulator of cell type identity. Overexpression of EZH2 has been detected in invasive breast carcinoma tissue samples and is observed in human breast tissue samples of morphologically normal lobules up to 12 years before the development of breast cancer. The function of EZH2 during preneoplastic progression in the mammary gland is unknown. To investigate the role of EZH2 in the mammary gland, we targeted the expression of EZH2 to mammary epithelial cells using the mouse mammary tumor virus long terminal repeat. EZH2 overexpression resulted in aberrant terminal end bud architecture. By the age of 4 months, 100% of female mouse mammary tumor virus-EZH2 virgin mice developed intraductal epithelial hyperplasia resembling the human counterpart accompanied by premature differentiation of ductal epithelial cells and up-regulation of the luminal marker GATA-3. In addition, remodeling of the mammary gland after parturition was impaired and EZH2 overexpression caused delayed involution. Mechanistically, we found that EZH2 physically interacts with beta-catenin, inducing beta-catenin nuclear accumulation in mammary epithelial cells and activating Wnt/beta-catenin signaling. The biological significance of these data to human hyperplasias is demonstrated by EZH2 up-regulation and colocalization with beta-catenin in human intraductal epithelial hyperplasia, the earliest histologically identifiable precursor of breast carcinoma.

Targeted Overexpression of EZH2 in the Mammary Gland Disrupts Ductal Morphogenesis and Causes Epithelial Hyperplasia

PubMed Central

Li, Xin; Gonzalez, Maria E.; Toy, Katherine; Filzen, Tracey; Merajver, Sofia D.; Kleer, Celina G.

2009-01-01

The Polycomb group protein enhancer of zeste homolog 2 (EZH2), which has roles during development of numerous tissues, is a critical regulator of cell type identity. Overexpression of EZH2 has been detected in invasive breast carcinoma tissue samples and is observed in human breast tissue samples of morphologically normal lobules up to 12 years before the development of breast cancer. The function of EZH2 during preneoplastic progression in the mammary gland is unknown. To investigate the role of EZH2 in the mammary gland, we targeted the expression of EZH2 to mammary epithelial cells using the mouse mammary tumor virus long terminal repeat. EZH2 overexpression resulted in aberrant terminal end bud architecture. By the age of 4 months, 100% of female mouse mammary tumor virus-EZH2 virgin mice developed intraductal epithelial hyperplasia resembling the human counterpart accompanied by premature differentiation of ductal epithelial cells and up-regulation of the luminal marker GATA-3. In addition, remodeling of the mammary gland after parturition was impaired and EZH2 overexpression caused delayed involution. Mechanistically, we found that EZH2 physically interacts with β-catenin, inducing β-catenin nuclear accumulation in mammary epithelial cells and activating Wnt/β-catenin signaling. The biological significance of these data to human hyperplasias is demonstrated by EZH2 up-regulation and colocalization with β-catenin in human intraductal epithelial hyperplasia, the earliest histologically identifiable precursor of breast carcinoma. PMID:19661437

A novel closed cell culture device for fabrication of corneal epithelial cell sheets.

PubMed

Nakajima, Ryota; Kobayashi, Toyoshige; Moriya, Noboru; Mizutani, Manabu; Kan, Kazutoshi; Nozaki, Takayuki; Saitoh, Kazuo; Yamato, Masayuki; Okano, Teruo; Takeda, Shizu

2015-11-01

Automation technology for cell sheet-based tissue engineering would need to optimize the cell sheet fabrication process, stabilize cell sheet quality and reduce biological contamination risks. Biological contamination must be avoided in clinical settings. A closed culture system provides a solution for this. In the present study, we developed a closed culture device called a cell cartridge, to be used in a closed cell culture system for fabricating corneal epithelial cell sheets. Rabbit limbal epithelial cells were cultured on the surface of a porous membrane with 3T3 feeder cells, which are separate from the epithelial cells in the cell cartridges and in the cell-culture inserts as a control. To fabricate the stratified cell sheets, five different thicknesses of the membranes which were welded to the cell cartridge, were examined. Multilayered corneal epithelial cell sheets were fabricated in cell cartridges that were welded to a 25 µm-thick gas-permeable membrane, which was similar to the results with the cell-culture inserts. However, stratification of corneal epithelial cell sheets did not occur with cell cartridges that were welded to 100-300 µm-thick gas-permeable membranes. The fabricated cell sheets were evaluated by histological analyses to examine the expression of corneal epithelial-specific markers. Immunohistochemical analyses showed that a putative stem cell marker, p63, a corneal epithelial differentiation maker, CK3, and a barrier function marker, Claudin-1, were expressed in the appropriate position in the cell sheets. These results suggest that the cell cartridge is effective for fabricating corneal epithelial cell sheets. Copyright © 2012 John Wiley & Sons, Ltd.

Epithelial-to-mesenchymal transition in penile squamous cell carcinoma.

PubMed

Masferrer, Emili; Ferrándiz-Pulido, Carla; Masferrer-Niubò, Magalí; Rodríguez-Rodríguez, Alfredo; Gil, Inmaculada; Pont, Antoni; Servitje, Octavi; García de Herreros, Antonio; Lloveras, Belen; García-Patos, Vicenç; Pujol, Ramon M; Toll, Agustí; Hernández-Muñoz, Inmaculada

2015-02-01

Epithelial-to-mesenchymal transition is a phenomenon in epithelial tumors that involves loss of intercellular adhesion, mesenchymal phenotype acquisition and enhanced migratory potential. While the epithelial-to-mesenchymal transition process has been extensively linked to metastatic progression of squamous cell carcinoma, studies of the role of epithelial-to-mesenchymal transition in squamous cell carcinoma containing high risk human papillomaviruses are scarce. Moreover, to our knowledge epithelial-to-mesenchymal transition involvement in human penile squamous cell carcinoma, which can arise through transforming HPV infections or independently of HPV, has not been investigated. We evaluated the presence of epithelial-to-mesenchymal transition markers and their relationship to HPV in penile squamous cell carcinoma. We assessed the expression of E-cadherin, vimentin and the epithelial-to-mesenchymal transition related transcription factors Twist, Zeb1 and Snail by immunohistochemical staining in 64 penile squamous cell carcinoma cases. HPV was detected by polymerase chain reaction amplification. Simultaneous loss of membranous E-cadherin expression and vimentin over expression were noted in 43.5% of penile squamous cell carcinoma cases. HPV was significantly associated with loss of membranous E-cadherin but not with epithelial-to-mesenchymal transition. Recurrence and mortality rates were significantly higher in cases showing epithelial-to-mesenchymal transition. Our findings indicate that in penile squamous cell carcinoma epithelial-to-mesenchymal transition is associated with poor prognosis but not with the presence of HPV. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Epithelial cells as alternative human biomatrices for comet assay.

PubMed

Rojas, Emilio; Lorenzo, Yolanda; Haug, Kristiane; Nicolaissen, Bjørn; Valverde, Mahara

2014-01-01

The comet assay is a valuable experimental tool aimed at mapping DNA damage in human cells in vivo for environmental and occupational monitoring, as well as for therapeutic purposes, such as storage prior to transplant, during tissue engineering, and in experimental ex vivo assays. Furthermore, due to its great versatility, the comet assay allows to explore the use of alternative cell types to assess DNA damage, such as epithelial cells. Epithelial cells, as specialized components of many organs, have the potential to serve as biomatrices that can be used to evaluate genotoxicity and may also serve as early effect biomarkers. Furthermore, 80% of solid cancers are of epithelial origin, which points to the importance of studying DNA damage in these tissues. Indeed, studies including comet assay in epithelial cells have either clear clinical applications (lens and corneal epithelial cells) or examine genotoxicity within human biomonitoring and in vitro studies. We here review improvements in determining DNA damage using the comet assay by employing lens, corneal, tear duct, buccal, and nasal epithelial cells. For some of these tissues invasive sampling procedures are needed. Desquamated epithelial cells must be obtained and dissociated prior to examination using the comet assay, and such procedures may induce varying amounts of DNA damage. Buccal epithelial cells require lysis enriched with proteinase K to obtain free nucleosomes. Over a 30 year period, the comet assay in epithelial cells has been little employed, however its use indicates that it could be an extraordinary tool not only for risk assessment, but also for diagnosis, prognosis of treatments and diseases.

Epithelial cells as alternative human biomatrices for comet assay

PubMed Central

Rojas, Emilio; Lorenzo, Yolanda; Haug, Kristiane; Nicolaissen, Bjørn; Valverde, Mahara

2014-01-01

The comet assay is a valuable experimental tool aimed at mapping DNA damage in human cells in vivo for environmental and occupational monitoring, as well as for therapeutic purposes, such as storage prior to transplant, during tissue engineering, and in experimental ex vivo assays. Furthermore, due to its great versatility, the comet assay allows to explore the use of alternative cell types to assess DNA damage, such as epithelial cells. Epithelial cells, as specialized components of many organs, have the potential to serve as biomatrices that can be used to evaluate genotoxicity and may also serve as early effect biomarkers. Furthermore, 80% of solid cancers are of epithelial origin, which points to the importance of studying DNA damage in these tissues. Indeed, studies including comet assay in epithelial cells have either clear clinical applications (lens and corneal epithelial cells) or examine genotoxicity within human biomonitoring and in vitro studies. We here review improvements in determining DNA damage using the comet assay by employing lens, corneal, tear duct, buccal, and nasal epithelial cells. For some of these tissues invasive sampling procedures are needed. Desquamated epithelial cells must be obtained and dissociated prior to examination using the comet assay, and such procedures may induce varying amounts of DNA damage. Buccal epithelial cells require lysis enriched with proteinase K to obtain free nucleosomes. Over a 30 year period, the comet assay in epithelial cells has been little employed, however its use indicates that it could be an extraordinary tool not only for risk assessment, but also for diagnosis, prognosis of treatments and diseases. PMID:25506353

Establishment of immortal swine kidney epithelial cells.

PubMed

Kwak, Sungwook; Jung, Ji-Eun; Jin, Xun; Kim, Sun-Myung; Kim, Tae-Kyung; Lee, Joong-Seob; Lee, Soo-Yeon; Pian, Xumin; You, Seungkwon; Kim, Hyunggee; Choi, Yun-Jaie

2006-01-01

Using normal swine kidney epithelial (SKE) cells that were shown to be senescent at passages 12 to 14, we have established one lifespan-extended cell line and two lifespan-extended cell lines by exogenous introduction of the human catalytic subunit of telomerase (hTERT) and simian virus 40 large T-antigen (SV40LT), all of which maintain epithelial morphology and express cytokeratin, a marker of epithelial cells. SV40LT- and hTERT-transduced immortal cell lines appeared to be smaller and exhibited more uniform morphology relative to primary and spontaneously immortalized SKE cells. We determined the in vitro lifespan of primary SKE cells using a standard 3T6 protocol. There were two steps of the proliferation barrier at 12 and 20, in which a majority of primary SKE cells appeared enlarged, flattened, vacuolated, and ss-galactosidase-positive, all phenotypical characteristics of senescent cells. Lifespan-extended SKE cells were eventually established from most of the cellular foci, which is indicative of spontaneous cellular conversion at passage 23. Beyond passage 25, the rate of population doubling of the established cells gradually increased. At passage 30, immortal cell lines grew faster than primary counterpart cells in 10% FBS-DMEM culture conditions, and only SV40LT-transduced immortal cells grew faster than primary and other SKE immortal cells in 0.5% FBS-DMEM. These lifespan-extended SKE cell lines failed to grow in an anchorage-independent manner in soft-agar dishes. Hence, three immortalized swine kidney epithelial cells that are not transformed would be valuable biological tools for virus propagation and basic kidney epithelial cell research.

Type 2 innate lymphoid cells disrupt bronchial epithelial barrier integrity by targeting tight junctions through IL-13 in asthmatic patients.

PubMed

Sugita, Kazunari; Steer, Catherine A; Martinez-Gonzalez, Itziar; Altunbulakli, Can; Morita, Hideaki; Castro-Giner, Francesc; Kubo, Terufumi; Wawrzyniak, Paulina; Rückert, Beate; Sudo, Katsuko; Nakae, Susumu; Matsumoto, Kenji; O'Mahony, Liam; Akdis, Mübeccel; Takei, Fumio; Akdis, Cezmi A

2018-01-01

Bronchial epithelial barrier leakiness and type 2 innate lymphoid cells (ILC2s) have been separately linked to asthma pathogenesis; however, the influence of ILC2s on the bronchial epithelial barrier has not been investigated previously. We investigated the role of ILC2s in the regulation of bronchial epithelial tight junctions (TJs) and barrier function both in bronchial epithelial cells of asthmatic patients and healthy subjects and general innate lymphoid cell- and ILC2-deficient mice. Cocultures of human ILC2s and bronchial epithelial cells were used to determine transepithelial electrical resistance, paracellular flux, and TJ mRNA and protein expressions. The effect of ILC2s on TJs was examined by using a murine model of IL-33-induced airway inflammation in wild-type, recombination-activating gene 2 (Rag2) -/- , Rag2 -/- Il2rg -/- , and Rora sg/sg mice undergoing bone marrow transplantation to analyze the in vivo relevance of barrier disruption by ILC2s. ILC2s significantly impaired the epithelial barrier, as demonstrated by reduced transepithelial electrical resistance and increased fluorescein isothiocyanate-dextran permeability in air-liquid interface cultures of human bronchial epithelial cells. This was in parallel to decreased mRNAs and disrupted protein expression of TJ proteins and was restored by neutralization of IL-13. Intranasal administration of recombinant IL-33 to wild-type and Rag2 -/- mice lacking T and B cells triggered TJ disruption, whereas Rag2 -/- Il2rg -/- and Rora sg/sg mice undergoing bone marrow transplantation that lack ILC2s did not show any barrier leakiness. Direct nasal administration of IL-13 was sufficient to induce deficiency in the TJ barrier in the bronchial epithelium of mice in vivo. These data highlight an essential mechanism in asthma pathogenesis by demonstrating that ILC2s are responsible for bronchial epithelial TJ barrier leakiness through IL-13. Copyright © 2017 American Academy of Allergy, Asthma & Immunology

A potential adjuvant chemotherapeutics, 18β-glycyrrhetinic acid, inhibits renal tubular epithelial cells apoptosis via enhancing BMP-7 epigenetically through targeting HDAC2.

PubMed

Ma, Taotao; Huang, Cheng; Meng, Xiaoming; Li, Xiaofeng; Zhang, Yilong; Ji, Shuai; Li, Jun; Ye, Min; Liang, Hong

2016-05-05

Cisplatin, a highly effective and widely used chemotherapeutic agent, has a major limitation for its nephrotoxicity. We recently identified a novel strategy for attenuating its nephrotoxicity in chemotherapy by an effective adjuvant via epigenetic modification through targeting HDAC2. Molecular docking and SPR assay firstly reported that 18βGA, major metabolite of GA, could directly bind to HDAC2 and inhibit the activity of HDAC2. The effects and mechanisms of GA and 18βGA were assessed in CP-induced AKI in C57BL/6 mice, and in CP-treated HK-2 and mTEC cells lines. TUNEL and FCM results confirmed that GA and 18βGA could inhibit apoptosis of renal tubular epithelial cells induced by CP in vivo and in vitro. Western blot and immunofluorescence results demonstrated that the expression of BMP-7 was clearly induced by 18βGA in AKI models while siRNA BMP-7 could reduce the inhibitory effect of 18βGA on apoptosis. Results of current study indicated that 18βGA inhibited apoptosis of renal tubular epithelial cells via enhancing the level of BMP-7 epigenetically through targeting HDAC2, therefore protecting against CP-induced AKI. These available evidence, which led to an improved understanding of molecular recognition, suggested that 18βGA could serve as a potential clinical adjuvant in chemotherapy.

Characterization of newly established bovine intestinal epithelial cell line.

PubMed

Miyazawa, Kohtaro; Hondo, Tetsuya; Kanaya, Takashi; Tanaka, Sachi; Takakura, Ikuro; Itani, Wataru; Rose, Michael T; Kitazawa, Haruki; Yamaguchi, Takahiro; Aso, Hisashi

2010-01-01

Membranous epithelial cells (M cells) of the follicle-associated epithelium in Peyer's patches have a high capacity for transcytosis of several viruses and microorganisms. Here, we report that we have successfully established a bovine intestinal epithelial cell line (BIE cells) and developed an in vitro M cell model. BIE cells have a cobblestone morphology and microvilli-like structures, and strongly express cell-to-cell junctional proteins and cytokeratin, which is a specific intermediate filament protein of epithelial cells. After co-culture with murine intestinal lymphocytes or treatment with supernatant from bovine PBMC cultured with IL-2, BIE cells acquired the ability of transcytosis. Therefore, BIE cells have typical characteristics of bovine intestinal epithelial cells and also have the ability to differentiate into an M cell like linage. In addition, our results indicate that contact between immune cells and epithelial cells may not be absolutely required for the differentiation of M cells. We think that BIE cells will be useful for studying the transport mechanisms of various pathogens and also the evaluation of drug delivery via M cells.

Mesenchymal precursor cells maintain the differentiation and proliferation potentials of breast epithelial cells

PubMed Central

2014-01-01

Introduction Stromal-epithelial interactions play a fundamental role in tissue homeostasis, controlling cell proliferation and differentiation. Not surprisingly, aberrant stromal-epithelial interactions contribute to malignancies. Studies of the cellular and molecular mechanisms underlying these interactions require ex vivo experimental model systems that recapitulate the complexity of human tissue without compromising the differentiation and proliferation potentials of human primary cells. Methods We isolated and characterized human breast epithelial and mesenchymal precursors from reduction mammoplasty tissue and tagged them with lentiviral vectors. We assembled heterotypic co-cultures and compared mesenchymal and epithelial cells to cells in corresponding monocultures by analyzing growth, differentiation potentials, and gene expression profiles. Results We show that heterotypic culture of non-immortalized human primary breast epithelial and mesenchymal precursors maintains their proliferation and differentiation potentials and constrains their growth. We further describe the gene expression profiles of stromal and epithelial cells in co-cultures and monocultures and show increased expression of the tumor growth factor beta (TGFβ) family member inhibin beta A (INHBA) in mesenchymal cells grown as co-cultures compared with monocultures. Notably, overexpression of INHBA in mesenchymal cells increases colony formation potential of epithelial cells, suggesting that it contributes to the dynamic reciprocity between breast mesenchymal and epithelial cells. Conclusions The described heterotypic co-culture system will prove useful for further characterization of the molecular mechanisms mediating interactions between human normal or neoplastic breast epithelial cells and the stroma, and will provide a framework to test the relevance of the ever-increasing number of oncogenomic alterations identified in human breast cancer. PMID:24916766

Immortalization of normal human mammary epithelial cells in two steps by direct targeting of senescence barriers does not require gross genomic alterations

DOE PAGES

Garbe, James C.; Vrba, Lukas; Sputova, Klara; ...

2014-10-29

Telomerase reactivation and immortalization are critical for human carcinoma progression. However, little is known about the mechanisms controlling this crucial step, due in part to the paucity of experimentally tractable model systems that can examine human epithelial cell immortalization as it might occur in vivo. We achieved efficient non-clonal immortalization of normal human mammary epithelial cells (HMEC) by directly targeting the 2 main senescence barriers encountered by cultured HMEC. The stress-associated stasis barrier was bypassed using shRNA to p16INK4; replicative senescence due to critically shortened telomeres was bypassed in post-stasis HMEC by c-MYC transduction. Thus, 2 pathologically relevant oncogenic agentsmore » are sufficient to immortally transform normal HMEC. The resultant non-clonal immortalized lines exhibited normal karyotypes. Most human carcinomas contain genomically unstable cells, with widespread instability first observed in vivo in pre-malignant stages; in vitro, instability is seen as finite cells with critically shortened telomeres approach replicative senescence. Our results support our hypotheses that: (1) telomere-dysfunction induced genomic instability in pre-malignant finite cells may generate the errors required for telomerase reactivation and immortalization, as well as many additional “passenger” errors carried forward into resulting carcinomas; (2) genomic instability during cancer progression is needed to generate errors that overcome tumor suppressive barriers, but not required per se; bypassing the senescence barriers by direct targeting eliminated a need for genomic errors to generate immortalization. Achieving efficient HMEC immortalization, in the absence of “passenger” genomic errors, should facilitate examination of telomerase regulation during human carcinoma progression, and exploration of agents that could prevent immortalization.« less

Concise Review: Aggressive Colorectal Cancer: Role of Epithelial Cell Adhesion Molecule in Cancer Stem Cells and Epithelial-to-Mesenchymal Transition.

PubMed

Boesch, Maximilian; Spizzo, Gilbert; Seeber, Andreas

2018-06-01

Colorectal cancer (CRC) is one of the most common malignancies worldwide. In spite of various attempts to ameliorate outcome by escalating treatment, significant improvement is lacking particularly in the adjuvant setting. It has been proposed that cancer stem cells (CSCs) and the epithelial-to-mesenchymal transition (EMT) are at least partially responsible for therapy resistance in CRC. The epithelial cell adhesion molecule (EpCAM) was one of the first CSC antigens to be described. Furthermore, an EpCAM-specific antibody (edrecolomab) has the merit of having launched the era of monoclonal antibody treatment in oncology in the 1990s. However, despite great initial enthusiasm, monoclonal antibody treatment has not proven successful in the adjuvant treatment of CRC patients. In the meantime, new insights into the function of EpCAM in CRC have emerged and new drugs targeting various epitopes have been developed. In this review article, we provide an update on the role of EpCAM in CSCs and EMT, and emphasize the potential predictive selection criteria for novel treatment strategies and refined clinical trial design. Stem Cells Translational Medicine 2018;7:495-501. © 2018 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Functional relevance of intestinal epithelial cells in inflammatory bowel disease.

PubMed

Okamoto, Ryuichi; Watanabe, Mamoru

2016-01-01

The intestinal epithelium constitutes a physical barrier between inner and outer side of our body. It also functions as a "hub" which connects factors that determine the development of inflammatory bowel disease, such as microbiota, susceptibility genes, and host immune response. Accordingly, recent studies have implicated and further featured the role of intestinal epithelial cell dysfunction in the pathophysiology of inflammatory bowel disease. For example, mucin producing goblet cells are usually "depleted" in ulcerative colitis patients. Studies have shown that those goblet cells exhibit various immune-regulatory functions in addition to mucin production, such as antigen presentation or cytokine production. Paneth cells are another key cell lineage that has been deeply implicated in the pathophysiology of Crohn's disease. Several susceptibility genes for Crohn's disease may lead to impairment of anti-bacterial peptide production and secretion by Paneth cells. Also, other susceptibility genes may determine the survival of Paneth cells, which leads to reduced Paneth cell function in the patient small intestinal mucosa. Further studies may reveal other unexpected roles of the intestinal epithelium in the pathophysiology of inflammatory bowel disease, and may help to develop alternative therapies targeted to intestinal epithelial cell functions.

MET signalling in primary colon epithelial cells leads to increased transformation irrespective of aberrant Wnt signalling

PubMed Central

Boon, E M J; Kovarikova, M; Derksen, P W B; van der Neut, R

2005-01-01

It has been shown that in hereditary and most sporadic colon tumours, components of the Wnt pathway are mutated. The Wnt target MET has been implicated in the development of colon cancer. Here, we show that overexpression of wild-type or a constitutively activated form of MET in colon epithelial cells leads to increased transformation irrespective of Wnt signalling. Fetal human colon epithelial cells without aberrant Wnt signalling were transfected with wild-type or mutated MET constructs. Expression of these constructs leads to increased phosphorylation of MET and its downstream targets PKB and MAPK. Upon stimulation with HGF, the expression of E-cadherin is downregulated in wild-type MET-transfected cells, whereas cells expressing mutated MET show low E-cadherin levels independent of stimulation with ligand. This implies a higher migratory propensity of these cells. Furthermore, fetal human colon epithelial cells expressing the mutated form of MET have colony-forming capacity in soft agar, while cells expressing wild-type MET show an intermediate phenotype. Subcutaneous injection of mutated MET-transfected cells in nude mice leads to the formation of tumours within 12 days in all mice injected. At this time point, mock-transfected cells do not form tumours, while wild-type MET-transfected cells form subcutaneous tumours in one out of five mice. We thus show that MET signalling can lead to increased transformation of colon epithelial cells independent of Wnt signalling and in this way could play an essential role in the onset and progression of colorectal cancer. PMID:15785735

Intestinal epithelial cell-specific RARα depletion results in aberrant epithelial cell homeostasis and underdeveloped immune system.

PubMed

Jijon, H B; Suarez-Lopez, L; Diaz, O E; Das, S; De Calisto, J; Yaffe, M B; Pittet, M J; Mora, J R; Belkaid, Y; Xavier, R J; Villablanca, E J

2018-05-01

Retinoic acid (RA), a dietary vitamin A metabolite, is crucial in maintaining intestinal homeostasis. RA acts on intestinal leukocytes to modulate their lineage commitment and function. Although the role of RA has been characterized in immune cells, whether intestinal epithelial cells (IECs) rely on RA signaling to exert their immune-regulatory function has not been examined. Here we demonstrate that lack of RA receptor α (RARα) signaling in IECs results in deregulated epithelial lineage specification, leading to increased numbers of goblet cells and Paneth cells. Mechanistically, lack of RARα resulted in increased KLF4 + goblet cell precursors in the distal bowel, whereas RA treatment inhibited klf4 expression and goblet cell differentiation in zebrafish. These changes in secretory cells are associated with increased Reg3g, reduced luminal bacterial detection, and an underdeveloped intestinal immune system, as evidenced by an almost complete absence of lymphoid follicles and gut resident mononuclear phagocytes. This underdeveloped intestinal immune system shows a decreased ability to clear infection with Citrobacter rodentium. Collectively, our findings indicate that epithelial cell-intrinsic RARα signaling is critical to the global development of the intestinal immune system.

Stability of Reference Gene Expression After Porcine Sapelovirus Infection in Porcine Intestinal Epithelial Cells.

PubMed

Huang, Yong; Chen, Yabing; Sun, Huan; Lan, Daoliang

2016-01-01

Intestinal epithelial cells, which serve as the first physical barrier to protect intestinal tract from external antigens, have an important role in the local innate immunity. Screening of reference genes that have stable expression levels after viral infection in porcine intestinal epithelial cells is critical for ensuring the reliability of the expression analysis on anti-infection genes in porcine intestinal epithelial cells. In this study, nine common reference genes in pigs, including ACTB, B2M, GAPDH, HMBS, SDHA, HPRT1, TBP, YWHAZ, and RPL32, were chosen as the candidate reference genes. Porcine sapelovirus (PSV) was used as a model virus to infect porcine intestinal epithelial cell line (IPEC-J2). The expression stability of the nine genes was assessed by the geNorm, NormFinder, and BestKeeper software. Moreover, RefFinder program was used to evaluate the analytical results of above three softwares, and a relative expression experiment of selected target gene was used to verify the analysis results. The comprehensive results indicated that the gene combination of TBP and RPL32 has the most stable expression, which could be considered as an appropriate reference gene for research on gene expression after PSV infection in IPEC-J2cells. The results provided essential data for expression analysis of anti-infection genes in porcine intestinal epithelial cells.

Profiling human breast epithelial cells using single cell RNA sequencing identifies cell diversity.

PubMed

Nguyen, Quy H; Pervolarakis, Nicholas; Blake, Kerrigan; Ma, Dennis; Davis, Ryan Tevia; James, Nathan; Phung, Anh T; Willey, Elizabeth; Kumar, Raj; Jabart, Eric; Driver, Ian; Rock, Jason; Goga, Andrei; Khan, Seema A; Lawson, Devon A; Werb, Zena; Kessenbrock, Kai

2018-05-23

Breast cancer arises from breast epithelial cells that acquire genetic alterations leading to subsequent loss of tissue homeostasis. Several distinct epithelial subpopulations have been proposed, but complete understanding of the spectrum of heterogeneity and differentiation hierarchy in the human breast remains elusive. Here, we use single-cell mRNA sequencing (scRNAseq) to profile the transcriptomes of 25,790 primary human breast epithelial cells isolated from reduction mammoplasties of seven individuals. Unbiased clustering analysis reveals the existence of three distinct epithelial cell populations, one basal and two luminal cell types, which we identify as secretory L1- and hormone-responsive L2-type cells. Pseudotemporal reconstruction of differentiation trajectories produces one continuous lineage hierarchy that closely connects the basal lineage to the two differentiated luminal branches. Our comprehensive cell atlas provides insights into the cellular blueprint of the human breast epithelium and will form the foundation to understand how the system goes awry during breast cancer.

Interaction with Epithelial Cells Modifies Airway Macrophage Response to Ozone

EPA Science Inventory

The initial innate immune response to ozone (03) in the lung is orchestrated by structural cells, such as epithelial cells, and resident immune cells, such as airway macrophages (Macs). We developed an epithelial cell-Mac coculture model to investigate how epithelial cell-derived...

[Primary culture of human normal epithelial cells].

PubMed

Tang, Yu; Xu, Wenji; Guo, Wanbei; Xie, Ming; Fang, Huilong; Chen, Chen; Zhou, Jun

2017-11-28

The traditional primary culture methods of human normal epithelial cells have disadvantages of low activity of cultured cells, the low cultivated rate and complicated operation. To solve these problems, researchers made many studies on culture process of human normal primary epithelial cell. In this paper, we mainly introduce some methods used in separation and purification of human normal epithelial cells, such as tissue separation method, enzyme digestion separation method, mechanical brushing method, red blood cell lysis method, percoll layered medium density gradient separation method. We also review some methods used in the culture and subculture, including serum-free medium combined with low mass fraction serum culture method, mouse tail collagen coating method, and glass culture bottle combined with plastic culture dish culture method. The biological characteristics of human normal epithelial cells, the methods of immunocytochemical staining, trypan blue exclusion are described. Moreover, the factors affecting the aseptic operation, the conditions of the extracellular environment, the conditions of the extracellular environment during culture, the number of differential adhesion, and the selection and dosage of additives are summarized.

Characterization of cultivated murine lacrimal gland epithelial cells

PubMed Central

Kobayashi, Shinya; Kawashima, Motoko; Okada, Naoko; Mishima, Kenji; Saito, Ichiro; Ito, Masataka; Shimmura, Shigeto; Tsubota, Kazuo

2012-01-01

Purpose To date, mouse lacrimal gland epithelial cells have been cultured successfully but only in cases involving newborn mouse lacrimal glands. In this work, we attempted to cultivate and characterize adult mouse lacrimal gland epithelial cells. Methods Lacrimal glands were removed from newborn mice (C57B/6) and isolated lacrimal gland epithelial cells were seeded onto tissue culture treated or low adherent culture dishes in Cnt-07 culture medium with or without cholera toxin. Cultivated cells were characterized by immunostaining with pan-cytokeratin, α-smooth muscle actin, and lactoferrin antibodies. Lacrimal gland cells from 7-week-old green fluorescent protein (GFP) and non-GFP (C57B/6) mice were mixed and seeded onto uncoated dishes to assess sphere-forming efficiency. Cells were also seeded onto 3T3 cell feeder layers to assess colony forming efficiency. Results Lacrimal gland epithelial cells were selectively cultured with cholera toxin, and cell type was verified by pan-cytokeratin and α-smooth muscle actin immunostaining. Sphere formation from single cells of adult mice was observed using specific medium and low adherent culture dishes. These cells could also undergo colony formation on 3T3 feeder cells. Conclusions Adult mouse lacrimal gland epithelial cells were successfully cultivated in cholera toxin-containing medium, and were observed to form spheres from single cells. PMID:22665974

Protein tyrosine phosphatase σ targets apical junction complex proteins in the intestine and regulates epithelial permeability

PubMed Central

Murchie, Ryan; Guo, Cong-Hui; Persaud, Avinash; Muise, Aleixo; Rotin, Daniela

2014-01-01

Protein tyrosine phosphatase (PTP)σ (PTPRS) was shown previously to be associated with susceptibility to inflammatory bowel disease (IBD). PTPσ−/− mice exhibit an IBD-like phenotype in the intestine and show increased susceptibility to acute models of murine colitis. However, the function of PTPσ in the intestine is uncharacterized. Here, we show an intestinal epithelial barrier defect in the PTPσ−/− mouse, demonstrated by a decrease in transepithelial resistance and a leaky intestinal epithelium that was determined by in vivo tracer analysis. Increased tyrosine phosphorylation was observed at the plasma membrane of epithelial cells lining the crypts of the small bowel and colon of the PTPσ−/− mouse, suggesting the presence of PTPσ substrates in these regions. Using mass spectrometry, we identified several putative PTPσ intestinal substrates that were hyper–tyrosine-phosphorylated in the PTPσ−/− mice relative to wild type. Among these were proteins that form or regulate the apical junction complex, including ezrin. We show that ezrin binds to and is dephosphorylated by PTPσ in vitro, suggesting it is a direct PTPσ substrate, and identified ezrin-Y353/Y145 as important sites targeted by PTPσ. Moreover, subcellular localization of the ezrin phosphomimetic Y353E or Y145 mutants were disrupted in colonic Caco-2 cells, similar to ezrin mislocalization in the colon of PTPσ−/− mice following induction of colitis. Our results suggest that PTPσ is a positive regulator of intestinal epithelial barrier, which mediates its effects by modulating epithelial cell adhesion through targeting of apical junction complex-associated proteins (including ezrin), a process impaired in IBD. PMID:24385580

A multicenter study to standardize reporting and analyses of fluorescence-activated cell-sorted murine intestinal epithelial cells

PubMed Central

Magness, Scott T.; Puthoff, Brent J.; Crissey, Mary Ann; Dunn, James; Henning, Susan J.; Houchen, Courtney; Kaddis, John S.; Kuo, Calvin J.; Li, Linheng; Lynch, John; Martin, Martin G.; May, Randal; Niland, Joyce C.; Olack, Barbara; Qian, Dajun; Stelzner, Matthias; Swain, John R.; Wang, Fengchao; Wang, Jiafang; Wang, Xinwei; Yan, Kelley; Yu, Jian

2013-01-01

Fluorescence-activated cell sorting (FACS) is an essential tool for studies requiring isolation of distinct intestinal epithelial cell populations. Inconsistent or lack of reporting of the critical parameters associated with FACS methodologies has complicated interpretation, comparison, and reproduction of important findings. To address this problem a comprehensive multicenter study was designed to develop guidelines that limit experimental and data reporting variability and provide a foundation for accurate comparison of data between studies. Common methodologies and data reporting protocols for tissue dissociation, cell yield, cell viability, FACS, and postsort purity were established. Seven centers tested the standardized methods by FACS-isolating a specific crypt-based epithelial population (EpCAM+/CD44+) from murine small intestine. Genetic biomarkers for stem/progenitor (Lgr5 and Atoh 1) and differentiated cell lineages (lysozyme, mucin2, chromogranin A, and sucrase isomaltase) were interrogated in target and control populations to assess intra- and intercenter variability. Wilcoxon's rank sum test on gene expression levels showed limited intracenter variability between biological replicates. Principal component analysis demonstrated significant intercenter reproducibility among four centers. Analysis of data collected by standardized cell isolation methods and data reporting requirements readily identified methodological problems, indicating that standard reporting parameters facilitate post hoc error identification. These results indicate that the complexity of FACS isolation of target intestinal epithelial populations can be highly reproducible between biological replicates and different institutions by adherence to common cell isolation methods and FACS gating strategies. This study can be considered a foundation for continued method development and a starting point for investigators that are developing cell isolation expertise to study physiology and

KSA Antigen Ep-CAM Mediates Cell–Cell Adhesion of Pancreatic Epithelial Cells: Morphoregulatory Roles in Pancreatic Islet Development

PubMed Central

Cirulli, V.; Crisa, L.; Beattie, G.M.; Mally, M.I.; Lopez, A.D.; Fannon, A.; Ptasznik, A.; Inverardi, L.; Ricordi, C.; Deerinck, T.; Ellisman, M.; Reisfeld, R.A.; Hayek, A.

1998-01-01

Cell adhesion molecules (CAMs) are important mediators of cell–cell interactions and regulate cell fate determination by influencing growth, differentiation, and organization within tissues. The human pancarcinoma antigen KSA is a glycoprotein of 40 kD originally identified as a marker of rapidly proliferating tumors of epithelial origin. Interestingly, most normal epithelia also express this antigen, although at lower levels, suggesting that a dynamic regulation of KSA may occur during cell growth and differentiation. Recently, evidence has been provided that this glycoprotein may function as an epithelial cell adhesion molecule (Ep-CAM). Here, we report that Ep-CAM exhibits the features of a morphoregulatory molecule involved in the development of human pancreatic islets. We demonstrate that Ep-CAM expression is targeted to the lateral domain of epithelial cells of the human fetal pancreas, and that it mediates calcium-independent cell–cell adhesion. Quantitative confocal immunofluorescence in fetal pancreata identified the highest levels of Ep-CAM expression in developing islet-like cell clusters budding from the ductal epithelium, a cell compartment thought to comprise endocrine progenitors. A surprisingly reversed pattern was observed in the human adult pancreas, displaying low levels of Ep-CAM in islet cells and high levels in ducts. We further demonstrate that culture conditions promoting epithelial cell growth induce upregulation of Ep-CAM, whereas endocrine differentiation of fetal pancreatic epithelial cells, transplanted in nude mice, is associated with a downregulation of Ep-CAM expression. In addition, a blockade of Ep-CAM function by KS1/4 mAb induced insulin and glucagon gene transcription and translation in fetal pancreatic cell clusters. These results indicate that developmentally regulated expression and function of Ep-CAM play a morphoregulatory role in pancreatic islet ontogeny. PMID:9508783

Cell death at the intestinal epithelial front line.

PubMed

Delgado, Maria Eugenia; Grabinger, Thomas; Brunner, Thomas

2016-07-01

The intestinal epithelium represents the largest epithelial surface in our body. This single-cell-layer epithelium mediates important functions in the absorption of nutrients and in the maintenance of barrier function, preventing luminal microorganisms from invading the body. Due to its constant regeneration the intestinal epithelium is a tissue not only with very high proliferation rates but also with very prominent physiological and pathophysiological cell death induction. The normal physiological differentiation and maturation of intestinal epithelial cells leads to their shedding and apoptotic cell death within a few days, without disturbing the epithelial barrier integrity. In contrast excessive intestinal epithelial cell death induced by irradiation, drugs and inflammation severely impairs the vital functions of this tissue. In this review we discuss cell death processes in the intestinal epithelium in health and disease, with special emphasis on cell death triggered by the tumour necrosis factor receptor family. © 2015 FEBS.

EDAC: Epithelial defence against cancer-cell competition between normal and transformed epithelial cells in mammals.

PubMed

Kajita, Mihoko; Fujita, Yasuyuki

2015-07-01

During embryonic development or under certain pathological conditions, viable but suboptimal cells are often eliminated from the cellular society through a process termed cell competition. Cell competition was originally identified in Drosophila where cells with different properties compete for survival; 'loser' cells are eliminated from tissues and consequently 'winner' cells become dominant. Recent studies have shown that cell competition also occurs in mammals. While apoptotic cell death is the major fate for losers in Drosophila, outcompeted cells show more variable phenotypes in mammals, such as cell death-independent apical extrusion and cellular senescence. Molecular mechanisms underlying these processes have been recently revealed. Especially, in epithelial tissues, normal cells sense and actively eliminate the neighbouring transformed cells via cytoskeletal proteins by the process named epithelial defence against cancer (EDAC). Here, we introduce this newly emerging research field: cell competition in mammals. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Epithelial stem cells and intestinal cancer.

PubMed

Tan, Shawna; Barker, Nick

2015-06-01

The mammalian intestine is comprised of an epithelial layer that serves multiple functions in order to maintain digestive activity as well as intestinal homeostasis. This epithelial layer contains highly proliferative stem cells which facilitate its characteristic rapid regeneration. How these stem cells contribute to tissue repair and normal homeostasis are actively studied, and while we have a greater understanding of the molecular mechanisms and cellular locations that underlie stem cell regulation in this tissue, much still remains undiscovered. This review describes epithelial stem cells in both intestinal and non-intestinal tissues, as well as the strategies that have been used to further characterize the cells. Through a discussion of the current understanding of intestinal self-renewal and tissue regeneration in response to injury, we focus on how dysregulation of critical signaling pathways results in potentially oncogenic aberrations, and highlight issues that should be addressed in order for effective intestinal cancer therapies to be devised. Copyright © 2014 Elsevier Ltd. All rights reserved.

CUX1/Wnt signaling regulates Epithelial Mesenchymal Transition in EBV infected epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malizia, Andrea P.; Lacey, Noreen; Walls, Dermot

Idiopathic pulmonary fibrosis (IPF) is a refractory and lethal interstitial lung disease characterized by alveolar epithelial cells apoptosis, fibroblast proliferation and extra-cellular matrix protein deposition. EBV, localised to alveolar epithelial cells of pulmonary fibrosis patients is associated with a poor prognosis. A strategy based on microarray-differential gene expression analysis to identify molecular drivers of EBV-associated lung fibrosis was utilized. Alveolar epithelial cells were infected with EBV to identify genes whose expression was altered following TGF{beta}1-mediated lytic phase. EBV lytic reactivation by TGF{beta}1 drives a selective alteration in CUX1 variant (a) (NCBI accession number NM{sub 1}81552) expression, inducing activation of non-canonicalmore » Wnt pathway mediators, implicating it in Epithelial Mesenchymal Transition (EMT), the molecular event underpinning scar production in tissue fibrosis. The role of EBV in EMT can be attenuated by antiviral strategies and inhibition of Wnt signaling by using All-Trans Retinoic Acids (ATRA). Activation of non-canonical Wnt signaling pathway by EBV in epithelial cells suggests a novel mechanism of EMT via CUX1 signaling. These data present a framework for further description of the link between infectious agents and fibrosis, a significant disease burden.« less

Intracellular Insulin-like Growth Factor-I Induces Bcl-2 Expression in Airway Epithelial Cells 1

PubMed Central

Chand, Hitendra S.; Harris, Jennifer Foster; Mebratu, Yohannes; Chen, Yangde; Wright, Paul S.; Randell, Scott H.; Tesfaigzi, Yohannes

2012-01-01

Bcl-2, a prosurvival protein, regulates programmed cell death during development and repair processes, and can be oncogenic when cell proliferation is deregulated. The present study investigated what factors modulate Bcl-2 expression in airway epithelial cells and identified the pathways involved. Microarray analysis of mRNA from airway epithelial cells captured by laser microdissection showed that increased expression of IL-1β and IGF-1 coincided with induced Bcl-2 expression compared to controls. Treatment of cultured airway epithelial cells with IL-1β and IGF-1 induced Bcl-2 expression by increasing Bcl-2 mRNA stability with no discernible changes in promoter activity. Silencing the IGF-1 expression using shRNA showed that intracellular (IC)-IGF-1 was increasing Bcl-2 expression. Blocking EGFR or IGF-1R activation also suppressed IC-IGF-1, and abolished the Bcl-2 induction. Induced expression and co-localization of IC-IGF-1 and Bcl-2 were observed in airway epithelial cells of mice exposed to LPS or cigarette smoke and of patients with cystic fibrosis and chronic bronchitis but not in the respective controls. These studies demonstrate that IC-IGF-1 induces Bcl-2 expression in epithelial cells via IGF-1R and EGFR pathways, and targeting IC-IGF-1 could be beneficial to treat chronic airway diseases. PMID:22461702

Protein kinase D is increased and activated in lung epithelial cells and macrophages in idiopathic pulmonary fibrosis.

PubMed

Gan, Huachen; McKenzie, Raymond; Hao, Qin; Idell, Steven; Tang, Hua

2014-01-01

Idiopathic pulmonary fibrosis (IPF) is a relentlessly progressive and usually fatal lung disease of unknown etiology for which no effective treatments currently exist. Hence, there is a profound need for the identification of novel drugable targets to develop more specific and efficacious therapeutic intervention in IPF. In this study, we performed immunohistochemical analyses to assess the cell type-specific expression and activation of protein kinase D (PKD) family kinases in normal and IPF lung tissue sections. We also analyzed PKD activation and function in human lung epithelial cells. We found that PKD family kinases (PKD1, PKD2 and PKD3) were increased and activated in the hyperplastic and regenerative alveolar epithelial cells lining remodeled fibrotic alveolar septa and/or fibroblast foci in IPF lungs compared with normal controls. We also found that PKD family kinases were increased and activated in alveolar macrophages, bronchiolar epithelium, and honeycomb cysts in IPF lungs. Interestingly, PKD1 was highly expressed and activated in the cilia of IPF bronchiolar epithelial cells, while PKD2 and PKD3 were expressed in the cell cytoplasm and nuclei. In contrast, PKD family kinases were not apparently increased and activated in IPF fibroblasts or myofibroblasts. We lastly found that PKD was predominantly activated by poly-L-arginine, lysophosphatidic acid and thrombin in human lung epithelial cells and that PKD promoted epithelial barrier dysfunction. These findings suggest that PKD may participate in the pathogenesis of IPF and may be a novel target for therapeutic intervention in this disease.

Regulation of a Rho-associated kinase expression during the corneal epithelial cell cycle.

PubMed

Anderson, S C; SundarRaj, N

2001-04-01

It has been recognized that an increased expression of the Rho-associated kinase (ROCK-I), a downstream target of Rho (a Ras-related small guanosine triphosphatase [GTPase]), is associated with limbal-to-corneal epithelial transition. The purpose of the present study was to determine whether the expression of ROCK-I is regulated during the cell cycle of corneal epithelial cells. Rabbit corneal epithelial cells in culture were subjected to different culture conditions to enrich them in the G0, G1, and S phases of the cell cycle. Indirect immunofluorescence staining and western blot techniques were used for analyzing the changes in the relative intracellular concentrations of ROCK-I. Northern blot analysis of the isolated cellular RNA was performed to estimate the relative concentrations of ROCK-I mRNA. Serum deprivation did not cause all the corneal epithelial cells in culture to be arrested in the G0 phase of the cell cycle. However, the cells could be arrested in G0 by treating them with culture medium supplemented with transforming growth factor (TGF)-beta1. The relative concentration of ROCK-I in the G0-arrested cells was higher than in the corresponding control untreated cultures. G0-arrested cells were induced to enter G1, followed by the S phase of the cell cycle, by refeeding them with the medium devoid of TGF-beta1. The total intracellular concentration of ROCK-I significantly decreased during the G1 phase of the cell cycle and increased again during the S phase. The decrease in intracellular ROCK-I during the G1 phase was confirmed by arresting the cells in G1 with isoleucine deprivation and thymidine-mimosine treatments. ROCK-I mRNA levels were also found to be decreased during the G1 phase of the cell cycle. The levels of ROCK-I in the corneal epithelial cells were significantly lower in the G1 phase than those in the S and G0 phases of the cell cycle. Therefore, a Rho signaling pathway(s) involving ROCK-I may be regulated during the corneal epithelial

Inhibition of PTP1B disrupts cell–cell adhesion and induces anoikis in breast epithelial cells

PubMed Central

Hilmarsdottir, Bylgja; Briem, Eirikur; Halldorsson, Skarphedinn; Kricker, Jennifer; Ingthorsson, Sævar; Gustafsdottir, Sigrun; Mælandsmo, Gunhild M; Magnusson, Magnus K; Gudjonsson, Thorarinn

2017-01-01

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. PMID:28492548

Mesenchymal Stromal Cell-Derived Interleukin-6 Promotes Epithelial-Mesenchymal Transition and Acquisition of Epithelial Stem-Like Cell Properties in Ameloblastoma Epithelial Cells.

PubMed

Jiang, Chunmiao; Zhang, Qunzhou; Shanti, Rabie M; Shi, Shihong; Chang, Ting-Han; Carrasco, Lee; Alawi, Faizan; Le, Anh D

2017-09-01

Epithelial-mesenchymal transition (EMT), a biological process associated with cancer stem-like or cancer-initiating cell formation, contributes to the invasiveness, metastasis, drug resistance, and recurrence of the malignant tumors; it remains to be determined whether similar processes contribute to the pathogenesis and progression of ameloblastoma (AM), a benign but locally invasive odontogenic neoplasm. Here, we demonstrated that EMT- and stem cell-related genes were expressed in the epithelial islands of the most common histologic variant subtype, the follicular AM. Our results revealed elevated interleukin (IL)-6 signals that were differentially expressed in the stromal compartment of the follicular AM. To explore the stromal effect on tumor pathogenesis, we isolated and characterized both mesenchymal stromal cells (AM-MSCs) and epithelial cells (AM-EpiCs) from follicular AM and demonstrated that, in in vitro culture, AM-MSCs secreted a significantly higher level of IL-6 as compared to the counterpart AM-EpiCs. Furthermore, both in vitro and in vivo studies revealed that exogenous and AM-MSC-derived IL-6 induced the expression of EMT- and stem cell-related genes in AM-EpiCs, whereas such effects were significantly abrogated either by a specific inhibitor of STAT3 or ERK1/2, or by knockdown of Slug gene expression. These findings suggest that AM-MSC-derived IL-6 promotes tumor-stem like cell formation by inducing EMT process in AM-EpiCs through STAT3 and ERK1/2-mediated signaling pathways, implying a role in the etiology and progression of the benign but locally invasive neoplasm. Stem Cells 2017;35:2083-2094. © 2017 AlphaMed Press.

CLOCK regulates mammary epithelial cell growth and differentiation

PubMed Central

Crodian, Jennifer; Suárez-Trujillo, Aridany; Erickson, Emily; Weldon, Bethany; Crow, Kristi; Cummings, Shelby; Chen, Yulu; Shamay, Avi; Mabjeesh, Sameer J.; Plaut, Karen

2016-01-01

Circadian clocks influence virtually all physiological processes, including lactation. Here, we investigate the role of the CLOCK gene in regulation of mammary epithelial cell growth and differentiation. Comparison of mammary morphology in late-pregnant wild-type and ClockΔ19 mice, showed that gland development was negatively impacted by genetic loss of a functional timing system. To understand whether these effects were due, in part, to loss of CLOCK function in the gland, the mouse mammary epithelial cell line, HC11, was transfected with short hairpin RNA that targeted Clock (shClock). Cells transfected with shClock expressed 70% less Clock mRNA than wild-type (WT) HC11 cultures, which resulted in significantly depressed levels of CLOCK protein (P < 0.05). HC11 lines carrying shClock had four-fold higher growth rates (P < 0.05), and the percentage of cells in G1 phase was significantly higher (90.1 ± 1.1% of shClock vs. 71.3 ± 3.6% of WT-HC11) following serum starvation. Quantitative-PCR (qPCR) analysis showed shClock had significant effects (P < 0.0001) on relative expression levels of Ccnd1, Wee1, and Tp63. qPCR analysis of the effect of shClock on Fasn and Cdh1 expression in undifferentiated cultures and cultures treated 96 h with dexamethasone, insulin, and prolactin (differentiated) found levels were reduced by twofold and threefold, respectively (P < 0.05), in shClock line relative to WT cultures. Abundance of CDH1 and TP63 proteins were significantly reduced in cultures transfected with shClock. These data support how CLOCK plays a role in regulation of epithelial cell growth and differentiation in the mammary gland. PMID:27707717

Trafficking to the apical and basolateral membranes in polarized epithelial cells.

PubMed

Stoops, Emily H; Caplan, Michael J

2014-07-01

Renal epithelial cells must maintain distinct protein compositions in their apical and basolateral membranes in order to perform their transport functions. The creation of these polarized protein distributions depends on sorting signals that designate the trafficking route and site of ultimate functional residence for each protein. Segregation of newly synthesized apical and basolateral proteins into distinct carrier vesicles can occur at the trans-Golgi network, recycling endosomes, or a growing assortment of stations along the cellular trafficking pathway. The nature of the specific sorting signal and the mechanism through which it is interpreted can influence the route a protein takes through the cell. Cell type-specific variations in the targeting motifs of a protein, as are evident for Na,K-ATPase, demonstrate a remarkable capacity to adapt sorting pathways to different developmental states or physiologic requirements. This review summarizes our current understanding of apical and basolateral trafficking routes in polarized epithelial cells. Copyright © 2014 by the American Society of Nephrology.

Trafficking to the Apical and Basolateral Membranes in Polarized Epithelial Cells

PubMed Central

Stoops, Emily H.

2014-01-01

Renal epithelial cells must maintain distinct protein compositions in their apical and basolateral membranes in order to perform their transport functions. The creation of these polarized protein distributions depends on sorting signals that designate the trafficking route and site of ultimate functional residence for each protein. Segregation of newly synthesized apical and basolateral proteins into distinct carrier vesicles can occur at the trans-Golgi network, recycling endosomes, or a growing assortment of stations along the cellular trafficking pathway. The nature of the specific sorting signal and the mechanism through which it is interpreted can influence the route a protein takes through the cell. Cell type–specific variations in the targeting motifs of a protein, as are evident for Na,K-ATPase, demonstrate a remarkable capacity to adapt sorting pathways to different developmental states or physiologic requirements. This review summarizes our current understanding of apical and basolateral trafficking routes in polarized epithelial cells. PMID:24652803

Ciliary neurotrophic factor promotes the activation of corneal epithelial stem/progenitor cells and accelerates corneal epithelial wound healing.

PubMed

Zhou, Qingjun; Chen, Peng; Di, Guohu; Zhang, Yangyang; Wang, Yao; Qi, Xia; Duan, Haoyun; Xie, Lixin

2015-05-01

Ciliary neurotrophic factor (CNTF), a well-known neuroprotective cytokine, has been found to play an important role in neurogenesis and functional regulations of neural stem cells. As one of the most innervated tissue, however, the role of CNTF in cornea epithelium remains unclear. This study was to explore the roles and mechanisms of CNTF in the activation of corneal epithelial stem/progenitor cells and wound healing of both normal and diabetic mouse corneal epithelium. In mice subjecting to mechanical removal of corneal epithelium, the corneal epithelial stem/progenitor cell activation and wound healing were promoted by exogenous CNTF application, while delayed by CNTF neutralizing antibody. In cultured corneal epithelial stem/progenitor cells, CNTF enhanced the colony-forming efficiency, stimulated the mitogenic proliferation, and upregulated the expression levels of corneal epithelial stem/progenitor cell-associated transcription factors. Furthermore, the promotion of CNTF on the corneal epithelial stem/progenitor cell activation and wound healing was mediated by the activation of STAT3. Moreover, in diabetic mice, the content of CNTF in corneal epithelium decreased significantly when compared with that of normal mice, and the supplement of CNTF promoted the diabetic corneal epithelial wound healing, accompanied with the advanced activation of corneal epithelial stem/progenitor cells and the regeneration of corneal nerve fibers. Thus, the capability of expanding corneal epithelial stem/progenitor cells and promoting corneal epithelial wound healing and nerve regeneration indicates the potential application of CNTF in ameliorating limbal stem cell deficiency and treating diabetic keratopathy. © 2014 AlphaMed Press.

JS-K, a nitric oxide-releasing prodrug, induces breast cancer cell death while sparing normal mammary epithelial cells.

PubMed

McMurtry, Vanity; Saavedra, Joseph E; Nieves-Alicea, René; Simeone, Ann-Marie; Keefer, Larry K; Tari, Ana M

2011-04-01

Targeted therapy with reduced side effects is a major goal in cancer research. We investigated the effects of JS-K, a nitric oxide (NO) prodrug designed to release high levels of NO when suitably activated, on human breast cancer cell lines, on non-transformed human MCF-10A mammary cells, and on normal human mammary epithelial cells (HMECs). Cell viability assay, flow cytometry, electron microscopy, and Western blot analysis were used to study the effects of JS-K on breast cancer and on mammary epithelial cells. After a 3-day incubation, the IC50s of JS-K against the breast cancer cells ranged from 0.8 to 3 µM. However, JS-K decreased the viability of the MCF-10A cells by only 20% at 10-µM concentration, and HMECs were unaffected by 10 µM JS-K. Flow cytometry indicated that JS-K increased the percentages of breast cancer cells under-going apoptosis. Interestingly, flow cytometry indicated that JS-K increased acidic vesicle organelle formation in breast cancer cells, suggesting that JS-K induced autophagy in breast cancer cells. Electron microscopy confirmed that JS-K-treated breast cancer cells underwent autophagic cell death. Western blot analysis showed that JS-K induced the expression of microtubule light chain 3-II, another autophagy marker, in breast cancer cells. However, JS-K did not induce apoptosis or autophagy in normal human mammary epithelial cells. These data indicate that JS-K selectively induces programmed cell death in breast cancer cells while sparing normal mammary epithelial cells under the same conditions. The selective anti-tumor activity of JS-K warrants its further investigation in breast tumors.

Mechanical stretch triggers rapid epithelial cell division through Piezo1.

PubMed

Gudipaty, S A; Lindblom, J; Loftus, P D; Redd, M J; Edes, K; Davey, C F; Krishnegowda, V; Rosenblatt, J

2017-03-02

Despite acting as a barrier for the organs they encase, epithelial cells turn over at some of the fastest rates in the body. However, epithelial cell division must be tightly linked to cell death to preserve barrier function and prevent tumour formation. How does the number of dying cells match those dividing to maintain constant numbers? When epithelial cells become too crowded, they activate the stretch-activated channel Piezo1 to trigger extrusion of cells that later die. However, it is unclear how epithelial cell division is controlled to balance cell death at the steady state. Here we show that mammalian epithelial cell division occurs in regions of low cell density where cells are stretched. By experimentally stretching epithelia, we find that mechanical stretch itself rapidly stimulates cell division through activation of the Piezo1 channel. To stimulate cell division, stretch triggers cells that are paused in early G2 phase to activate calcium-dependent phosphorylation of ERK1/2, thereby activating the cyclin B transcription that is necessary to drive cells into mitosis. Although both epithelial cell division and cell extrusion require Piezo1 at the steady state, the type of mechanical force controls the outcome: stretch induces cell division, whereas crowding induces extrusion. How Piezo1-dependent calcium transients activate two opposing processes may depend on where and how Piezo1 is activated, as it accumulates in different subcellular sites with increasing cell density. In sparse epithelial regions in which cells divide, Piezo1 localizes to the plasma membrane and cytoplasm, whereas in dense regions in which cells extrude, it forms large cytoplasmic aggregates. Because Piezo1 senses both mechanical crowding and stretch, it may act as a homeostatic sensor to control epithelial cell numbers, triggering extrusion and apoptosis in crowded regions and cell division in sparse regions.

Genetics and epithelial cell dysfunction in cystic fibrosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riordan, J.R.; Buchwald, M.

1987-01-01

This book examines the advances being made in the study of the physiology, cell biology, and molecular genetics of cystic fibrosis. Emphasis is placed on various areas of research that involve epithelial cells (e.g., the CF-specific phenotypes exhibited by epithelial cells, abnormalities in epithelium ion transport, chloride channel regulation in CF epithelial.) Coverage is presented on the current status of CF, including data on the incidence of the disease, its mode of inheritance, chromosomal localization, genetic heterogeneity, and screening and management.

Niche-induced cell death and epithelial phagocytosis regulate hair follicle stem cell pool.

PubMed

Mesa, Kailin R; Rompolas, Panteleimon; Zito, Giovanni; Myung, Peggy; Sun, Thomas Y; Brown, Samara; Gonzalez, David G; Blagoev, Krastan B; Haberman, Ann M; Greco, Valentina

2015-06-04

Tissue homeostasis is achieved through a balance of cell production (growth) and elimination (regression). In contrast to tissue growth, the cells and molecular signals required for tissue regression remain unknown. To investigate physiological tissue regression, we use the mouse hair follicle, which cycles stereotypically between phases of growth and regression while maintaining a pool of stem cells to perpetuate tissue regeneration. Here we show by intravital microscopy in live mice that the regression phase eliminates the majority of the epithelial cells by two distinct mechanisms: terminal differentiation of suprabasal cells and a spatial gradient of apoptosis of basal cells. Furthermore, we demonstrate that basal epithelial cells collectively act as phagocytes to clear dying epithelial neighbours. Through cellular and genetic ablation we show that epithelial cell death is extrinsically induced through transforming growth factor (TGF)-β activation and mesenchymal crosstalk. Strikingly, our data show that regression acts to reduce the stem cell pool, as inhibition of regression results in excess basal epithelial cells with regenerative abilities. This study identifies the cellular behaviours and molecular mechanisms of regression that counterbalance growth to maintain tissue homeostasis.

Pre-existing Epithelial Diversity in Normal Human Livers: A Tissue-tethered Cytometric Analysis in Portal/Periportal Epithelial Cells

PubMed Central

Isse, Kumiko; Lesniak, Andrew; Grama, Kedar; Maier, John; Specht, Susan; Castillo-Rama, Marcela; Lunz, John; Roysam, Badrinath; Michalopoulos, George; Demetris, Anthony J.

2012-01-01

Routine light microscopy identifies two distinct epithelial cell populations in normal human livers: hepatocytes and biliary epithelial cells (BEC). Considerable epithelial diversity, however, arises during disease states when a variety of hepatocyte-BEC hybrid cells appear. This has been attributed to activation and differentiation of putative hepatic progenitor cells (HPC) residing in the Canals of Hering and/or metaplasia of pre-existing mature epithelial cells. A novel analytic approach consisting of multiplex labeling, high resolution whole slide imaging (WSI), and automated image analysis was used to determine if more complex epithelial cell phenotypes pre-existed in normal adult human livers, which might provide an alternative explanation for disease-induced epithelial diversity. “Virtually digested” WSI enabled quantitative cytometric analyses of individual cells displayed in a variety of formats (e.g. scatter plots) while still tethered to the WSI and tissue structure. We employed biomarkers specifically-associated with mature epithelial forms (HNF4α for hepatocytes, CK19 and HNF1β for BEC) and explored for the presence of cells with hybrid biomarker phenotypes. Results showed abundant hybrid cells in portal bile duct BEC, canals of Hering, and immediate periportal hepatocytes. These bi-potential cells likely serve as a reservoir for the epithelial diversity of ductular reactions, appearance of hepatocytes in bile ducts, and the rapid and fluid transition of BEC to hepatocytes, and vice versa. Conclusion Novel imaging and computational tools enable increased information extraction from tissue samples and quantify the considerable pre-existent hybrid epithelial diversity in normal human liver. This computationally-enabled tissue analysis approach offers much broader potential beyond the results presented here. PMID:23150208

Persistent Transmissible Gastroenteritis Virus Infection Enhances Enterotoxigenic Escherichia coli K88 Adhesion by Promoting Epithelial-Mesenchymal Transition in Intestinal Epithelial Cells.

PubMed

Xia, Lu; Dai, Lei; Yu, Qinghua; Yang, Qian

2017-11-01

Transmissible gastroenteritis virus (TGEV) is a coronavirus characterized by diarrhea and high morbidity rates, and the mortality rate is 100% in piglets less than 2 weeks old. Pigs infected with TGEV often suffer secondary infection by other pathogens, which aggravates the severity of diarrhea, but the mechanisms remain unknown. Here, we hypothesized that persistent TGEV infection stimulates the epithelial-mesenchymal transition (EMT), and thus enterotoxigenic Escherichia coli (ETEC) can more easily adhere to generating cells. Intestinal epithelial cells are the primary targets of TGEV and ETEC infections. We found that TGEV can persistently infect porcine intestinal columnar epithelial cells (IPEC-J2) and cause EMT, consistent with multiple changes in key cell characteristics. Infected cells display fibroblast-like shapes; exhibit increases in levels of mesenchymal markers with a corresponding loss of epithelial markers; have enhanced expression levels of interleukin-1β (IL-1β), IL-6, IL-8, transforming growth factor β (TGF-β), and tumor necrosis factor alpha (TNF-α) mRNAs; and demonstrate increases in migratory and invasive behaviors. Additional experiments showed that the activation of the phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK) signaling pathways via TGF-β is critical for the TGEV-mediated EMT process. Cellular uptake is also modified in cells that have undergone EMT. TGEV-infected cells have higher levels of integrin α5 and fibronectin and exhibit enhanced ETEC K88 adhesion. Reversal of EMT reduces ETEC K88 adhesion and inhibits the expression of integrin α5 and fibronectin. Overall, these results suggest that TGEV infection induces EMT in IPEC-J2 cells, increasing the adhesion of ETEC K88 in the intestine and facilitating dual infection. IMPORTANCE Transmissible gastroenteritis virus (TGEV) causes pig diarrhea and is often followed by secondary infection by other pathogens. In this study, we showed

Cell reintegration: Stray epithelial cells make their way home.

PubMed

Wilson, Tyler J; Bergstralh, Dan T

2017-06-01

Ongoing work shows that misplaced epithelial cells have the capacity to reintegrate back into tissue layers. This movement appears to underlie tissue stability and may also control aspects of tissue structure. A recent study reveals that cell reintegration in at least one tissue, the Drosophila follicular epithelium, is based on adhesion molecules that line lateral cell surfaces. In this article we will review these observations, discuss their implications for epithelial tissue development and maintenance, and identify future directions for study. © 2017 WILEY Periodicals, Inc.

Live Imaging of HIV-1 Transfer across T Cell Virological Synapse to Epithelial Cells that Promotes Stromal Macrophage Infection.

PubMed

Real, Fernando; Sennepin, Alexis; Ganor, Yonatan; Schmitt, Alain; Bomsel, Morgane

2018-05-08

During sexual intercourse, HIV-1 crosses epithelial barriers composing the genital mucosa, a poorly understood feature that requires an HIV-1-infected cell vectoring efficient mucosal HIV-1 entry. Therefore, urethral mucosa comprising a polarized epithelium and a stroma composed of fibroblasts and macrophages were reconstructed in vitro. Using this system, we demonstrate by live imaging that efficient HIV-1 transmission to stromal macrophages depends on cell-mediated transfer of the virus through virological synapses formed between HIV-1-infected CD4 + T cells and the epithelial cell mucosal surface. We visualized HIV-1 translocation through mucosal epithelial cells via transcytosis in regions where virological synapses occurred. In turn, interleukin-13 is secreted and HIV-1 targets macrophages, which develop a latent state of infection reversed by lipopolysaccharide (LPS) activation. The live observation of virological synapse formation reported herein is key in the design of vaccines and antiretroviral therapies aimed at blocking HIV-1 access to cellular reservoirs in genital mucosa. Copyright © 2018. Published by Elsevier Inc.

Efficient genome editing of differentiated renal epithelial cells.

PubMed

Hofherr, Alexis; Busch, Tilman; Huber, Nora; Nold, Andreas; Bohn, Albert; Viau, Amandine; Bienaimé, Frank; Kuehn, E Wolfgang; Arnold, Sebastian J; Köttgen, Michael

2017-02-01

Recent advances in genome editing technologies have enabled the rapid and precise manipulation of genomes, including the targeted introduction, alteration, and removal of genomic sequences. However, respective methods have been described mainly in non-differentiated or haploid cell types. Genome editing of well-differentiated renal epithelial cells has been hampered by a range of technological issues, including optimal design, efficient expression of multiple genome editing constructs, attainable mutation rates, and best screening strategies. Here, we present an easily implementable workflow for the rapid generation of targeted heterozygous and homozygous genomic sequence alterations in renal cells using transcription activator-like effector nucleases (TALENs) and the clustered regularly interspaced short palindromic repeat (CRISPR) system. We demonstrate the versatility of established protocols by generating novel cellular models for studying autosomal dominant polycystic kidney disease (ADPKD). Furthermore, we show that cell culture-validated genetic modifications can be readily applied to mouse embryonic stem cells (mESCs) for the generation of corresponding mouse models. The described procedure for efficient genome editing can be applied to any cell type to study physiological and pathophysiological functions in the context of precisely engineered genotypes.

The Effect of Ozone on Colonic Epithelial Cells.

PubMed

Himuro, Hidetomo

2018-05-21

Due to its strong oxidation activity, ozone has been well known to kill bacteria and exert toxic effects on human tissues. At the same time, ozone is being used for the treatment of diseases such as inflammatory bowel disease in some European countries. However, the use of ozone for therapeutic purposes, despite its strong toxic effects, remains largely unexplored. Interestingly, we found that intrarectal administration of ozone gas induced transient colonic epithelial cell damage characterized by the impairment of cell survival pathways involved in DNA replication, cell cycle, and mismatch repair. However, the damaged cells were rapidly extruded from the epithelial layer, and appeared to immediately stimulate turnover of the epithelial layer in the colon. Therefore, it is possible that ozone gas is able to trigger damage-induced rapid regeneration of intestinal epithelial cells, and that this explains why ozone does not cause harmful or persistent damage in the colon.

Efficient Immortalization of Primary Nasopharyngeal Epithelial Cells for EBV Infection Study

PubMed Central

Yip, Yim Ling; Pang, Pei Shin; Deng, Wen; Tsang, Chi Man; Zeng, Musheng; Hau, Pok Man; Man, Cornelia; Jin, Yuesheng; Yuen, Anthony Po Wing; Tsao, Sai Wah

2013-01-01

Nasopharyngeal carcinoma (NPC) is common among southern Chinese including the ethnic Cantonese population living in Hong Kong. Epstein-Barr virus (EBV) infection is detected in all undifferentiated type of NPC in this endemic region. Establishment of stable and latent EBV infection in premalignant nasopharyngeal epithelial cells is an early event in NPC development and may contribute to its pathogenesis. Immortalized primary nasopharyngeal epithelial cells represent an important tool for investigation of EBV infection and its tumorigenic potential in this special type of epithelial cells. However, the limited availability and small sizes of nasopharyngeal biopsies have seriously restricted the establishment of primary nasopharyngeal epithelial cells for immortalization. A reliable and effective method to immortalize primary nasopharyngeal epithelial cells will provide unrestricted materials for EBV infection studies. An earlier study has reported that Bmi-1 expression could immortalize primary nasopharyngeal epithelial cells. However, its efficiency and actions in immortalization have not been fully characterized. Our studies showed that Bmi-1 expression alone has limited ability to immortalize primary nasopharyngeal epithelial cells and additional events are often required for its immortalization action. We have identified some of the key events associated with the immortalization of primary nasopharyngeal epithelial cells. Efficient immortalization of nasopharyngeal epithelial cells could be reproducibly and efficiently achieved by the combined actions of Bmi-1 expression, activation of telomerase and silencing of p16 gene. Activation of MAPK signaling and gene expression downstream of Bmi-1 were detected in the immortalized nasopharyngeal epithelial cells and may play a role in immortalization. Furthermore, these newly immortalized nasopharyngeal epithelial cells are susceptible to EBV infection and supported a type II latent EBV infection program characteristic

Hedgehog signaling plays roles in epithelial cell proliferation in neonatal mouse uterus and vagina.

PubMed

Nakajima, Tadaaki; Iguchi, Taisen; Sato, Tomomi

2012-04-01

Both the uterus and vagina develop from the Müllerian duct but are quite distinct in morphology and function. To investigate factors controlling epithelial differentiation and cell proliferation in neonatal uterus and vagina, we focused on Hedgehog (HH) signaling. In neonatal mice, Sonic hh (Shh) was localized in the vaginal epithelium and Indian hh (Ihh) was slightly expressed in the uterus and vagina, whereas all Glioma-associated oncogene homolog (Gli) genes were mainly expressed in the stroma. The expression of target genes of HH signaling was high in the neonatal vagina and in the uterus, it increased with growth. Thus, in neonatal mice, Shh in the vaginal epithelium and Ihh in the uterus and vagina activated HH signaling in the stroma. Tissue recombinants showed that vaginal Shh expression was inhibited by the vaginal stroma and uterine Ihh expression was stimulated by the uterine stroma. Addition of a HH signaling inhibitor decreased epithelial cell proliferation in organ-cultured uterus and vagina and increased stromal cell proliferation in organ-cultured uterus. However, it did not affect epithelial differentiation or the expression of growth factors in organ-cultured uterus and vagina. Thus, activated HH signaling stimulates epithelial cell proliferation in neonatal uterus and vagina but inhibits stromal cell proliferation in neonatal uterus.

IL-12 Can Target Human Lung Adenocarcinoma Cells and Normal Bronchial Epithelial Cells Surrounding Tumor Lesions

PubMed Central

Airoldi, Irma; Di Carlo, Emma; Cocco, Claudia; Caci, Emanuela; Cilli, Michele; Sorrentino, Carlo; Sozzi, Gabriella; Ferrini, Silvano; Rosini, Sandra; Bertolini, Giulia; Truini, Mauro; Grossi, Francesco; Galietta, Luis Juan Vicente; Ribatti, Domenico; Pistoia, Vito

2009-01-01

Background Non small cell lung cancer (NSCLC) is a leading cause of cancer death. We have shown previously that IL-12rb2 KO mice develop spontaneously lung adenocarcinomas or bronchioalveolar carcinomas. Aim of the study was to investigate i) IL-12Rβ2 expression in human primary lung adenocarcinomas and in their counterparts, i.e. normal bronchial epithelial cells (NBEC), ii) the direct anti-tumor activity of IL-12 on lung adenocarcinoma cells in vitro and vivo, and the mechanisms involved, and iii) IL-12 activity on NBEC. Methodology/Principal Findings Stage I lung adenocarcinomas showed significantly (P = 0.012) higher frequency of IL-12Rβ2 expressing samples than stage II/III tumors. IL-12 treatment of IL-12R+ neoplastic cells isolated from primary adenocarcinoma (n = 6) inhibited angiogenesis in vitro through down-regulation of different pro-angiogenic genes (e.g. IL-6, VEGF-C, VEGF-D, and laminin-5), as assessed by chorioallantoic membrane (CAM) assay and PCR array. In order to perform in vivo studies, the Calu6 NSCLC cell line was transfected with the IL-12RB2 containing plasmid (Calu6/β2). Similar to that observed in primary tumors, IL-12 treatment of Calu6/β2+ cells inhibited angiogenesis in vitro. Tumors formed by Calu6/β2 cells in SCID/NOD mice, inoculated subcutaneously or orthotopically, were significantly smaller following IL-12 vs PBS treatment due to inhibition of angiogenesis, and of IL-6 and VEGF-C production. Explanted tumors were studied by histology, immuno-histochemistry and PCR array. NBEC cells were isolated and cultured from lung specimens of non neoplastic origin. NBEC expressed IL-12R and released constitutively tumor promoting cytokines (e.g. IL-6 and CCL2). Treatment of NBEC with IL-12 down-regulated production of these cytokines. Conclusions This study demonstrates that IL-12 inhibits directly the growth of human lung adenocarcinoma and targets the adjacent NBEC. These novel anti-tumor activities of IL-12 add to the well

M2 polarization of macrophages facilitates arsenic-induced cell transformation of lung epithelial cells

PubMed Central

Li, Hui; Dai, Lu; Frank, Jacqueline A.; Peng, Shaojun; Wang, Siying; Chen, Gang

2017-01-01

The alterations in microenvironment upon chronic arsenic exposure may contribute to arsenic-induced lung carcinogenesis. Immune cells, such as macrophages, play an important role in mediating the microenvironment in the lungs. Macrophages carry out their functions after activation. There are two activation status for macrophages: classical (M1) or alternative (M2); the latter is associated with tumorigenesis. Our previous work showed that long-term arsenic exposure induces transformation of lung epithelial cells. However, the crosstalk between epithelial cells and macrophages upon arsenic exposure has not been investigated. In this study, using a co-culture system in which human lung epithelial cells are cultured with macrophages, we determined that long-term arsenic exposure polarizes macrophages towards M2 status through ROS generation. Co-culture with epithelial cells further enhanced the polarization of macrophages as well as transformation of epithelial cells, while blocking macrophage M2 polarization decreased the transformation. In addition, macrophage M2 polarization decreased autophagy activity, which may account for increased cell transformation of epithelial cells with co-culture of macrophages. PMID:28423485

Chitin-Induced Airway Epithelial Cell Innate Immune Responses Are Inhibited by Carvacrol/Thymol

PubMed Central

Erle, David J.

2016-01-01

Chitin is produced in large amounts by fungi, insects, and other organisms and has been implicated in the pathogenesis of asthma. Airway epithelial cells are in direct contact with environmental particles and serve as the first line of defense against inhaled allergens and pathogens. The potential contributions of airway epithelial cells to chitin-induced asthma remain poorly understood. We hypothesized that chitin directly stimulates airway epithelial cells to release cytokines that promote type 2 immune responses and to induce expression of molecules which are important in innate immune responses. We found that chitin exposure rapidly induced the expression of three key type 2-promoting cytokines, IL-25, IL-33 and TSLP, in BEAS-2B transformed human bronchial epithelial cells and in A549 and H292 lung carcinoma cells. Chitin also induced the expression of the key pattern recognition receptors TLR2 and TLR4. Chitin induced the expression of miR-155, miR-146a and miR-21, each of which is known to up-regulate the expression of pro-inflammatory cytokines. Also the expression of SOCS1 and SHIP1 which are known targets of miR-155 was repressed by chitin treatment. The monoterpene phenol carvacrol (Car) and its isomer thymol (Thy) are found in herbal essential oils and have been shown to inhibit allergic inflammation in asthma models. We found that Car/Thy inhibited the effects of chitin on type 2-promoting cytokine release and on the expression of TLRs, SOCS1, SHIP1, and miRNAs. Car/Thy could also efficiently reduce the protein levels of TLR4, inhibit the increase in TLR2 protein levels in chitin plus Car/Thy-treated cells and increase the protein levels of SHIP1 and SOCS1, which are negative regulators of TLR-mediated inflammatory responses. We conclude that direct effects of chitin on airway epithelial cells are likely to contribute to allergic airway diseases like asthma, and that Car/Thy directly inhibits epithelial cell pro-inflammatory responses to chitin. PMID

Niche induced cell death and epithelial phagocytosis regulate hair follicle stem cell pool

PubMed Central

Mesa, Kailin R.; Rompolas, Panteleimon; Zito, Giovanni; Myung, Peggy; Sun, Thomas Yang; Brown, Samara; Gonzalez, David; Blagoev, Krastan B.; Haberman, Ann M.; Greco, Valentina

2015-01-01

Summary Tissue homeostasis is achieved through a balance of cell production (growth) and elimination (regression)1,2. Contrary to tissue growth, the cells and molecular signals required for tissue regression remain unknown. To investigate physiological tissue regression, we use the mouse hair follicle, which cycles stereotypically between phases of growth and regression while maintaining a pool of stem cells to perpetuate tissue regeneration3. Here we show by intravital microscopy in live mice4–6 that the regression phase eliminates the majority of the epithelial cells by two distinct mechanisms: terminal differentiation of suprabasal cells and a spatial gradient of apoptosis of basal cells. Furthermore, we demonstrate that basal epithelial cells collectively act as phagocytes to clear dying epithelial neighbors. Through cellular and genetic ablation we show that epithelial cell death is extrinsically induced through TGFβ activation and mesenchymal crosstalk. Strikingly, our data show that regression acts to reduce the stem cell pool as inhibition of regression results in excess basal epithelial cells with regenerative abilities. This study identifies the cellular behaviors and molecular mechanisms of regression that counterbalance growth to maintain tissue homeostasis. PMID:25849774

Fabrication of corneal epithelial cell sheets maintaining colony-forming cells without feeder cells by oxygen-controlled method.

PubMed

Nakajima, Ryota; Takeda, Shizu

2014-01-01

The use of murine 3T3 feeder cells needs to be avoided when fabricating corneal epithelial cell sheets for use in treating ocular surface diseases. However, the expression level of the epithelial stem/progenitor cell marker, p63, is down-regulated in feeder-free culture systems. In this study, in order to fabricate corneal epithelial cell sheets that maintain colony-forming cells without using any feeder cells, we investigated the use of an oxygen-controlled method that was developed previously to fabricate cell sheets efficiently. Rabbit limbal epithelial cells were cultured under hypoxia (1-10% O2) and under normoxia during stratification after reaching confluence. Multilayered corneal epithelial cell sheets were fabricated using an oxygen-controlled method, and immunofluorescence analysis showed that cytokeratin 3 and p63 was expressed in appropriate localization in the cell sheets. The colony-forming efficiency of the cell sheets fabricated by the oxygen-controlled method without feeder cells was significantly higher than that of cell sheets fabricated under 20% O2 without feeder cells. These results indicate that the oxygen-controlled method has the potential to achieve a feeder-free culture system for fabricating corneal epithelial cell sheets for corneal regeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Airway epithelial cell response to human metapneumovirus infection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bao, X.; Liu, T.; Spetch, L.

2007-11-10

Human metapneumovirus (hMPV) is a major cause of lower respiratory tract infections (LRTIs) in infants, elderly and immunocompromised patients. In this study, we show that hMPV can infect in a similar manner epithelial cells representative of different tracts of the airways. hMPV-induced expression of chemokines IL-8 and RANTES in primary small alveolar epithelial cells (SAE) and in a human alveolar type II-like epithelial cell line (A549) was similar, suggesting that A549 cells can be used as a model to study lower airway epithelial cell responses to hMPV infection. A549 secreted a variety of CXC and CC chemokines, cytokines and typemore » I interferons, following hMPV infection. hMPV was also a strong inducer of transcription factors belonging to nuclear factor (NF)-{kappa}B, interferon regulatory factors (IRFs) and signal transducers and activators of transcription (STATs) families, which are known to orchestrate the expression of inflammatory and immunomodulatory mediators.« less

Curcumin targets fibroblast–tumor cell interactions in oral squamous cell carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dudás, József, E-mail: jozsef.dudas@i-med.ac.at; Fullár, Alexandra, E-mail: fullarsz@gmail.com; 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllői út 26, 1085 Budapest

Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of OSCC tumor cells. We hypothesized that Curcumin targets this dynamic mutual interaction between CAFs and tumor cells. Normal and 2 μM Curcumin-treated co-culture were performed for 4 days, followed by analysis of tumor cell invasivity, mRNA/protein expression of EMT-markers and mediators, activity measure of matrix metalloproteinase 9 (MMP-9), and western blot analysis of signal transduction in tumor cells and fibroblasts. In Curcumin-treated co-culture, in tumor cells, the levels of nuclear factormore » κB (NFκBα) and early response kinase (ERK)—decreased, in fibroblasts, integrin αv protein synthesis decreased compared to corresponding cells in normal co-culture. The signal modulatory changes induced by Curcumin caused decreased release of EMT-mediators in CAFs and reversal of EMT in tumor cells, which was associated with decreased invasion. These data confirm the palliative potential of Curcumin in clinical application. - Graphical abstract: Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of tumor cells. Curcumin targets this dynamic mutual interaction between CAFs and tumor cells by inhibiting the production of EMT mediators in CAFs and by modification of intracellular signaling in tumor cells. This causes less invasivity and reversal of EMT in tumor cells. Highlights: ► Curcumin targets tumor–fibroblast interaction in head and neck cancer. ► Curcumin suppresses mediators of epithelial–mesenchymal transition. ► Curcumin decreases the invasivity of tumor cells.« less

Multi-functionality and plasticity characterize epithelial cells in Hydra

PubMed Central

Buzgariu, W; Al Haddad, S; Tomczyk, S; Wenger, Y; Galliot, B

2015-01-01

Epithelial sheets, a synapomorphy of all metazoans but porifers, are present as 2 layers in cnidarians, ectoderm and endoderm, joined at their basal side by an extra-cellular matrix named mesoglea. In the Hydra polyp, epithelial cells of the body column are unipotent stem cells that continuously self-renew and concomitantly express their epitheliomuscular features. These multifunctional contractile cells maintain homeostasis by providing a protective physical barrier, by digesting nutrients, by selecting a stable microbiota, and by rapidly closing wounds. In addition, epithelial cells are highly plastic, supporting the adaptation of Hydra to physiological and environmental changes, such as long starvation periods where survival relies on a highly dynamic autophagy flux. Epithelial cells also play key roles in developmental processes as evidenced by the organizer activity they develop to promote budding and regeneration. We propose here an integrative view of the homeostatic and developmental aspects of epithelial plasticity in Hydra. PMID:26716072

Cell-to-Cell Contact and Nectin-4 Govern Spread of Measles Virus from Primary Human Myeloid Cells to Primary Human Airway Epithelial Cells.

PubMed

Singh, Brajesh K; Li, Ni; Mark, Anna C; Mateo, Mathieu; Cattaneo, Roberto; Sinn, Patrick L

2016-08-01

Measles is a highly contagious, acute viral illness. Immune cells within the airways are likely first targets of infection, and these cells traffic measles virus (MeV) to lymph nodes for amplification and subsequent systemic dissemination. Infected immune cells are thought to return MeV to the airways; however, the mechanisms responsible for virus transfer to pulmonary epithelial cells are poorly understood. To investigate this process, we collected blood from human donors and generated primary myeloid cells, specifically, monocyte-derived macrophages (MDMs) and dendritic cells (DCs). MDMs and DCs were infected with MeV and then applied to primary cultures of well-differentiated airway epithelial cells from human donors (HAE). Consistent with previous results obtained with free virus, infected MDMs or DCs were incapable of transferring MeV to HAE when applied to the apical surface. Likewise, infected MDMs or DCs applied to the basolateral surface of HAE grown on small-pore (0.4-μm) support membranes did not transfer virus. In contrast, infected MDMs and DCs applied to the basolateral surface of HAE grown on large-pore (3.0-μm) membranes successfully transferred MeV. Confocal microscopy demonstrated that MDMs and DCs are capable of penetrating large-pore membranes but not small-pore membranes. Further, by using a nectin-4 blocking antibody or recombinant MeV unable to enter cells through nectin-4, we demonstrated formally that transfer from immune cells to HAE occurs in a nectin-4-dependent manner. Thus, both infected MDMs and DCs rely on cell-to-cell contacts and nectin-4 to efficiently deliver MeV to the basolateral surface of HAE. Measles virus spreads rapidly and efficiently in human airway epithelial cells. This rapid spread is based on cell-to-cell contact rather than on particle release and reentry. Here we posit that MeV transfer from infected immune cells to epithelial cells also occurs by cell-to-cell contact rather than through cell-free particles. In

Role of Corneal Stromal Cells on Epithelial Cell Function during Wound Healing

PubMed Central

Kowtharapu, Bhavani S.; Murín, Radovan; Jünemann, Anselm G. M.; Stachs, Oliver

2018-01-01

Following injury, corneal stromal keratocytes transform into repair-phenotype of activated stromal fibroblasts (SFs) and participate in wound repair. Simultaneously, ongoing bi-directional communications between corneal stromal-epithelial cells also play a vital role in mediating the process of wound healing. Factors produced by stromal cells are known to induce proliferation, differentiation, and motility of corneal epithelial cells, which are also subsequently the main processes that occur during wound healing. In this context, the present study aims to investigate the effect of SFs conditioned medium (SFCM) on corneal epithelial cell function along with substance P (SP). Antibody microarrays were employed to profile differentially expressed cell surface markers and cytokines in the presence of SFCM and SP. Antibody microarray data revealed enhanced expression of the ITGB1 in corneal epithelial cells following stimulation with SP whereas SFCM induced abundant expression of IL-8, ITGB1, PD1L1, PECA1, IL-15, BDNF, ICAM1, CD8A, CD44 and NTF4. All these proteins have either direct or indirect roles in epithelial cell growth, movement and adhesion related signaling cascades during tissue regeneration. We also observed activation of MAPK signaling pathway along with increased expression of focal adhesion kinase (FAK), paxillin, vimentin, β-catenin and vasodilator-stimulated phosphoprotein (VASP) phosphorylation. Additionally, epithelial-to-mesenchymal transition (EMT) regulating transcription factors Slug and ZEB1 expression were enhanced in the presence of SFCM. SP enriched the expression of integrin subunits α4, α5, αV, β1 and β3 whereas SFCM increased α4, α5, αV, β1 and β5 integrin subunits. We also observed increased expression of Serpin E1 following SP and SFCM treatment. Wound healing scratch assay revealed enhanced migration of epithelial cells following the addition of SFCM. Taken together, we conclude that SFCM-mediated sustained activation of ZEB1

Alteration of Fatty Acid Oxidation in Tubular Epithelial Cells: From Acute Kidney Injury to Renal Fibrogenesis

PubMed Central

Simon, Noémie; Hertig, Alexandre

2015-01-01

Renal proximal tubular cells are the most energy-demanding cells in the body. The ATP that they use is mostly produced in their mitochondrial and peroxisomal compartments, by the oxidation of fatty acids. When those cells are placed under a biological stress, such as a transient hypoxia, fatty acid oxidation (FAO) is shut down for a period of time that outlasts injury, and carbohydrate oxidation does not take over. Facing those metabolic constraints, surviving tubular epithelial cells exhibit a phenotypic switch that includes cytoskeletal rearrangement and production of extracellular matrix proteins, most probably contributing to acute kidney injury-induced renal fibrogenesis, thence to the development of chronic kidney disease. Here, we review experimental evidence that dysregulation of FAO profoundly affects the fate of tubular epithelial cells, by promoting epithelial-to-mesenchymal transition, inflammation, and eventually interstitial fibrosis. Restoring physiological production of energy is undoubtedly a possible therapeutic approach to unlock the mesenchymal reprograming of tubular epithelial cells in the kidney. In this respect, the benefit of the use of fibrates is uncertain, but new drugs that could specifically target this metabolic pathway, and, hopefully, attenuate renal fibrosis merit future research. PMID:26301223

Human induced pluripotent stem cell differentiation and direct transdifferentiation into corneal epithelial-like cells

PubMed Central

Cieślar-Pobuda, Artur; Rafat, Mehrdad; Knoflach, Viktoria; Skonieczna, Magdalena; Hudecki, Andrzej; Małecki, Andrzej; Urasińska, Elżbieta; Ghavami, Seaid; Łos, Marek J.

2016-01-01

The corneal epithelium is maintained by a small pool of tissue stem cells located at the limbus. Through certain injuries or diseases this pool of stem cells may get depleted. This leads to visual impairment. Standard treatment options include autologous or allogeneic limbal stem cell (LSC) transplantation, however graft rejection and chronic inflammation lowers the success rate over long time. Induced pluripotent stem (iPS) cells have opened new possibilities for treating various diseases with patient specific cells, eliminating the risk of immune rejection. In recent years, several protocols have been developed, aimed at the differentiation of iPS cells into the corneal epithelial lineage by mimicking the environmental niche of limbal stem cells. However, the risk of teratoma formation associated with the use of iPS cells hinders most applications from lab into clinics. Here we show that the differentiation of iPS cells into corneal epithelial cells results in the expression of corneal epithelial markers showing a successful differentiation, but the process is long and the level of gene expression for the pluripotency markers does not vanish completely. Therefore we set out to determine a direct transdifferentiation approach to circumvent the intermediate state of pluripotency (iPS-stage). The resulting cells, obtained by direct transdifferentiation of fibroblasts into limbal cells, exhibited corneal epithelial cell morphology and expressed corneal epithelial markers. Hence we shows for the first time a direct transdifferentiation of human dermal fibroblasts into the corneal epithelial lineage that may serve as source for corneal epithelial cells for transplantation approaches. PMID:27275539

Epithelial-mesenchymal status influences how cells deposit fibrillin microfibrils.

PubMed

Baldwin, Andrew K; Cain, Stuart A; Lennon, Rachel; Godwin, Alan; Merry, Catherine L R; Kielty, Cay M

2014-01-01

Here, we show that epithelial-mesenchymal status influences how cells deposit extracellular matrix. Retinal pigmented epithelial (RPE) cells that expressed high levels of E-cadherin and had cell-cell junctions rich in zona occludens (ZO)-1, β-catenin and heparan sulfate, required syndecan-4 but not fibronectin or protein kinase C α (PKCα) to assemble extracellular matrix (fibrillin microfibrils and perlecan). In contrast, RPE cells that strongly expressed mesenchymal smooth muscle α-actin but little ZO-1 or E-cadherin, required fibronectin (like fibroblasts) and PKCα, but not syndecan-4. Integrins α5β1 and/or α8β1 and actomyosin tension were common requirements for microfibril deposition, as was heparan sulfate biosynthesis. TGFβ, which stimulates epithelial-mesenchymal transition, altered gene expression and overcame the dependency on syndecan-4 for microfibril deposition in epithelial RPE cells, whereas blocking cadherin interactions disrupted microfibril deposition. Renal podocytes had a transitional phenotype with pericellular β-catenin but little ZO-1; they required syndecan-4 and fibronectin for efficient microfibril deposition. Thus, epithelial-mesenchymal status modulates microfibril deposition.

The Contribution of the Airway Epithelial Cell to Host Defense.

PubMed

Stanke, Frauke

2015-01-01

In the context of cystic fibrosis, the epithelial cell has been characterized in terms of its ion transport capabilities. The ability of an epithelial cell to initiate CFTR-mediated chloride and bicarbonate transport has been recognized early as a means to regulate the thickness of the epithelial lining fluid and recently as a means to regulate the pH, thereby determining critically whether or not host defense proteins such as mucins are able to fold appropriately. This review describes how the epithelial cell senses the presence of pathogens and inflammatory conditions, which, in turn, facilitates the activation of CFTR and thus directly promotes pathogens clearance and innate immune defense on the surface of the epithelial cell. This paper summarizes functional data that describes the effect of cytokines, chemokines, infectious agents, and inflammatory conditions on the ion transport properties of the epithelial cell and relates these key properties to the molecular pathology of cystic fibrosis. Recent findings on the role of cystic fibrosis modifier genes that underscore the role of the epithelial ion transport in host defense and inflammation are discussed.

Carbon nanoparticles induce ceramide- and lipid raft-dependent signalling in lung epithelial cells: a target for a preventive strategy against environmentally-induced lung inflammation

PubMed Central

2012-01-01

Background Particulate air pollution in lung epithelial cells induces pathogenic endpoints like proliferation, apoptosis, and pro-inflammatory reactions. The activation of the epidermal growth factor receptor (EGFR) is a key event responsible for signalling events involving mitogen activated protein kinases specific for these endpoints. The molecular events leading to receptor activation however are not well understood. These events are relevant for the toxicological evaluation of inhalable particles as well as for potential preventive strategies in situations when particulate air pollution cannot be avoided. The current study therefore had the objective to elucidate membrane-coupled events leading to EGFR activation and the subsequent signalling cascade in lung epithelial cells. Furthermore, we aimed to identify the molecular target of ectoine, a biophysical active substance which we described to prevent carbon nanoparticle-induced lung inflammation. Methods Membrane signalling events were investigated in isolated lipid rafts from lung epithelial cells with regard to lipid and protein content of the signalling platforms. Using positive and negative intervention approaches, lipid raft changes, subsequent signalling events, and lung inflammation were investigated in vitro in lung epithelial cells (RLE-6TN) and in vivo in exposed animals. Results Carbon nanoparticle treatment specifically led to an accumulation of ceramides in lipid rafts. Detailed analyses demonstrated a causal link of ceramides and subsequent EGFR activation coupled with a loss of the receptor in the lipid raft fractions. In vitro and in vivo investigations demonstrate the relevance of these events for carbon nanoparticle-induced lung inflammation. Moreover, the compatible solute ectoine was able to prevent ceramide-mediated EGFR phosphorylation and subsequent signalling as well as lung inflammation in vivo. Conclusion The data identify a so far unknown event in pro-inflammatory signalling and

Role of the epithelial cell rests of Malassez in the development, maintenance and regeneration of periodontal ligament tissues.

PubMed

Xiong, Jimin; Gronthos, Stan; Bartold, P Mark

2013-10-01

Periodontitis is a highly prevalent inflammatory disease that results in damage to the tooth-supporting tissues, potentially leading to tooth loss. Periodontal tissue regeneration is a complex process that involves the collaboration of two hard tissues (cementum and alveolar bone) and two soft tissues (gingiva and periodontal ligament). To date, no periodontal-regenerative procedures provide predictable clinical outcomes. To understand the rational basis of regenerative procedures, a better understanding of the events associated with the formation of periodontal components will help to establish reliable strategies for clinical practice. An important aspect of this is the role of the Hertwig's epithelial root sheath in periodontal development and that of its descendants, the epithelial cell rests of Malassez, in the maintenance of the periodontium. An important structure during tooth root development, the Hertwig's epithelial root sheath is not only a barrier between the dental follicle and dental papilla cells but is also involved in determining the shape, size and number of roots and in the development of dentin and cementum, and may act as a source of mesenchymal progenitor cells for cementoblasts. In adulthood, the epithelial cell rests of Malassez are the only odontogenic epithelial population in the periodontal ligament. Although there is no general agreement on the functions of the epithelial cell rests of Malassez, accumulating evidence suggests that the putative roles of the epithelial cell rests of Malassez in adult periodontal ligament include maintaining periodontal ligament homeostasis to prevent ankylosis and maintain periodontal ligament space, to prevent root resorption, to serve as a target during periodontal ligament innervation and to contribute to cementum repair. Recently, ovine epithelial cell rests of Malassez cells have been shown to harbor clonogenic epithelial stem-cell populations that demonstrate similar properties to mesenchymal stromal

Canine corneal epithelial cells possess a sustained proliferative capacity and generate a spontaneously derived cell line.

PubMed

Morita, Maresuke; Fujita, Naoki; Abe, Momoko; Hayashimoto, Koji; Nakagawa, Takayuki; Nishimura, Ryohei; Tsuzuki, Keiko

2018-06-01

We have previously reported characteristics of canine corneal epithelial cells in vitro and found that canine corneal epithelial cells could maintain their proliferative capacity even after continuous culture without the use of feeder cells and growth promoting additives. The objective of this study was to elucidate proliferative characteristics of canine corneal epithelial cells independent of feeder cells and growth promoting additives, with the aim of developing a spontaneously derived corneal epithelial cell line. Canine and rabbit corneal epithelial cells were harvested from the limbus and cultured with, or without, feeder cells and growth promoting additives, and both were passaged continuously until growth arrest. Canine corneal epithelial cells could proliferate independently, and could be passaged more times than rabbit cells. A canine corneal epithelial cell line, cCEpi, which could be passaged more than 100 times without using feeder cells and growth promoting additives, was established. cCEpi cells maintained a cell morphology close to the primary culture and expressed p63, cytokeratin 15 (K15), and K3. Although changes in colony morphology, shortening of the population doubling time and a heteroploid karyotype were observed, cCEpi was not tumorigenic. Stratified cell sheets cultured from cCEpi were morphologically and immunohistologically similar to sheets cultivated from early passage cells. In conclusion, canine corneal epithelial cells can proliferate independent of feeder cells and growth promoting additives. cCEpi maintains properties similar to normal corneal epithelial cells and could be a useful source for studies in cellular biology and for developing novel therapies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Study designs to investigate Nox1 acceleration of neoplastic progression in immortalized human epithelial cells by selection of differentiation resistant cells.

PubMed

Sattayakhom, Apsorn; Chunglok, Warangkana; Ittarat, Wanida; Chamulitrat, Walee

2014-01-01

To investigate the role of NADPH oxidase homolog Nox1 at an early step of cell transformation, we utilized human gingival mucosal keratinocytes immortalized by E6/E7 of human papillomavirus (HPV) type 16 (GM16) to generate progenitor cell lines either by chronic ethanol exposure or overexpression with Nox1. Among several cobblestone epithelial cell lines obtained, two distinctive spindle cell lines - FIB and NuB1 cells were more progressively transformed exhibiting tubulogenesis and anchorage-independent growth associated with increased invasiveness. These spindle cells acquired molecular markers of epithelial mesenchymal transition (EMT) including mesenchymal vimentin and simple cytokeratins (CK) 8 and 18 as well as myogenic alpha-smooth muscle actin and caldesmon. By overexpression and knockdown experiments, we showed that Nox1 on a post-translational level regulated the stability of CK18 in an ROS-, phosphorylation- and PKCepilon-dependent manner. PKCepilon may thus be used as a therapeutic target for EMT inhibition. Taken together, Nox1 accelerates neoplastic progression by regulating structural intermediate filaments leading to EMT of immortalized human gingival epithelial cells.

Cytokeratin 5 positive cells represent a therapy resistant subpopulation in epithelial ovarian cancer

PubMed Central

Corr, Bradley R.; Finlay-Schultz, Jessica; Rosen, Rachel B.; Qamar, Lubna; Post, Miriam D.; Behbakht, Kian; Spillman, Monique A.; Sartorius, Carol A.

2015-01-01

Objective Cytokeratin 5 (CK5) is an epithelial cell marker implicated in stem and progenitor cell activity in glandular reproductive tissues and endocrine and chemotherapy resistance in estrogen receptor (ER)+ breast cancer. The goal of this study was to determine the prevalence of CK5 expression in ovarian cancer and the response of CK5+ cell populations to cisplatin therapy. Materials and Methods CK5 expression was evaluated in two ovarian tissue microarrays, representing 137 neoplasms, and six ovarian cancer cell lines. Cell lines were treated with IC50 cisplatin and the prevalence of CK5+ cells pre- and post-treatment determined. Proliferation of CK5+ vs. CK5− cell populations was determined using bromodeoxyuridine (BrdU) incorporation. Chemotherapy induced apoptosis in CK5+ vs. CK5− cells was measured using immunohistochemical staining for cleaved caspase-3. Results CK5 was expressed in 39.3% (42/107) of epithelial ovarian cancers with a range of 1-80% positive cells. Serous and endometrioid histologic subtypes had the highest percentage of CK5+ specimens. CK5 expression correlated with ER positivity (38/42 CK5+ tumors were also ER+). CK5 was expressed in 5/6 overall and 4/4 ER+ epithelial ovarian cancer cell lines ranging from 2.4-52.7% positive cells. CK5+ compared to CK5− cells were slower proliferating. The prevalence of CK5+ cells increased following 48 hour cisplatin treatment in 4/5 cell lines tested. CK5+ compared to CK5− ovarian cancer cells were more resistant to cisplatin induced apoptosis. Conclusions CK5 is expressed in a significant proportion of epithelial ovarian cancers and represents a slower proliferating, chemoresistant subpopulation that may warrant co-targeting in combination therapy. PMID:26495758

Implantation of Induced Pluripotent Stem Cell-Derived Tracheal Epithelial Cells.

PubMed

Ikeda, Masakazu; Imaizumi, Mitsuyoshi; Yoshie, Susumu; Nakamura, Ryosuke; Otsuki, Koshi; Murono, Shigeyuki; Omori, Koichi

2017-07-01

Compared with using autologous tissue, the use of artificial materials in the regeneration of tracheal defects is minimally invasive. However, this technique requires early epithelialization on the inner side of the artificial trachea. After differentiation from induced pluripotent stem cells (iPSCs), tracheal epithelial tissues may be used to produce artificial tracheas. Herein, we aimed to demonstrate that after differentiation from fluorescent protein-labeled iPSCs, tracheal epithelial tissues survived in nude rats with tracheal defects. Red fluorescent tdTomato protein was electroporated into mouse iPSCs to produce tdTomato-labeled iPSCs. Embryoid bodies derived from these iPSCs were then cultured in differentiation medium supplemented with growth factors, followed by culture on air-liquid interfaces for further differentiation into tracheal epithelium. The cells were implanted with artificial tracheas into nude rats with tracheal defects on day 26 of cultivation. On day 7 after implantation, the tracheas were exposed and examined histologically. Tracheal epithelial tissue derived from tdTomato-labeled iPSCs survived in the tracheal defects. Moreover, immunochemical analyses showed that differentiated tissues had epithelial structures similar to those of proximal tracheal tissues. After differentiation from iPSCs, tracheal epithelial tissues survived in rat bodies, warranting the use of iPSCs for epithelial regeneration in tracheal defects.

The increase of microRNA-21 during lung fibrosis and its contribution to epithelial-mesenchymal transition in pulmonary epithelial cells.

PubMed

Yamada, Mitsuhiro; Kubo, Hiroshi; Ota, Chiharu; Takahashi, Toru; Tando, Yukiko; Suzuki, Takaya; Fujino, Naoya; Makiguchi, Tomonori; Takagi, Kiyoshi; Suzuki, Takashi; Ichinose, Masakazu

2013-09-24

The excess and persistent accumulation of fibroblasts due to aberrant tissue repair results in fibrotic diseases such as idiopathic pulmonary fibrosis. Recent reports have revealed significant changes in microRNAs during idiopathic pulmonary fibrosis and evidence in support of a role for microRNAs in myofibroblast differentiation and the epithelial-mesenchymal transition in the context of fibrosis. It has been reported that microRNA-21 is up-regulated in myofibroblasts during fibrosis and promotes transforming growth factor-beta signaling by inhibiting Smad7. However, expression changes in microRNA-21 and the role of microRNA-21 in epithelial-mesenchymal transition during lung fibrosis have not yet been defined. Lungs from saline- or bleomycin-treated C57BL/6 J mice and lung specimens from patients with idiopathic pulmonary fibrosis were analyzed. Enzymatic digestions were performed to isolate single lung cells. Lung epithelial cells were isolated by flow cytometric cell sorting. The expression of microRNA-21 was analyzed using both quantitative PCR and in situ hybridization. To induce epithelial-mesenchymal transition in culture, isolated mouse lung alveolar type II cells were cultured on fibronectin-coated chamber slides in the presence of transforming growth factor-β, thus generating conditions that enhance epithelial-mesenchymal transition. To investigate the role of microRNA-21 in epithelial-mesenchymal transition, we transfected cells with a microRNA-21 inhibitor. Total RNA was isolated from the freshly isolated and cultured cells. MicroRNA-21, as well as mRNAs of genes that are markers of alveolar epithelial or mesenchymal cell differentiation, were quantified using quantitative PCR. The lung epithelial cells isolated from the bleomycin-induced lung fibrosis model system had decreased expression of epithelial marker genes, whereas the expression of mesenchymal marker genes was increased. MicroRNA-21 was significantly upregulated in isolated lung epithelial

The Rap GTPase Activator Drosophila PDZ-GEF Regulates Cell Shape in Epithelial Migration and Morphogenesis▿

PubMed Central

Boettner, Benjamin; Van Aelst, Linda

2007-01-01

Epithelial morphogenesis is characterized by an exquisite control of cell shape and position. Progression through dorsal closure in Drosophila gastrulation depends on the ability of Rap1 GTPase to signal through the adherens junctional multidomain protein Canoe. Here, we provide genetic evidence that epithelial Rap activation and Canoe effector usage are conferred by the Drosophila PDZ-GEF (dPDZ-GEF) exchange factor. We demonstrate that dPDZ-GEF/Rap/Canoe signaling modulates cell shape and apicolateral cell constriction in embryonic and wing disc epithelia. In dPDZ-GEF mutant embryos with strong dorsal closure defects, cells in the lateral ectoderm fail to properly elongate. Postembryonic dPDZ-GEF mutant cells generated in mosaic tissue display a striking extension of lateral cell perimeters in the proximity of junctional complexes, suggesting a loss of normal cell contractility. Furthermore, our data indicate that dPDZ-GEF signaling is linked to myosin II function. Both dPDZ-GEF and cno show strong genetic interactions with the myosin II-encoding gene, and myosin II distribution is severely perturbed in epithelia of both mutants. These findings provide the first insight into the molecular machinery targeted by Rap signaling to modulate epithelial plasticity. We propose that dPDZ-GEF-dependent signaling functions as a rheostat linking Rap activity to the regulation of cell shape in epithelial morphogenesis at different developmental stages. PMID:17846121

Proximal location of mouse prostate epithelial stem cells

PubMed Central

Tsujimura, Akira; Koikawa, Yasuhiro; Salm, Sarah; Takao, Tetsuya; Coetzee, Sandra; Moscatelli, David; Shapiro, Ellen; Lepor, Herbert; Sun, Tung-Tien; Wilson, E. Lynette

2002-01-01

Stem cells are believed to regulate normal prostatic homeostasis and to play a role in the etiology of prostate cancer and benign prostatic hyperplasia. We show here that the proximal region of mouse prostatic ducts is enriched in a subpopulation of epithelial cells that exhibit three important attributes of epithelial stem cells: they are slow cycling, possess a high in vitro proliferative potential, and can reconstitute highly branched glandular ductal structures in collagen gels. We propose a model of prostatic homeostasis in which mouse prostatic epithelial stem cells are concentrated in the proximal region of prostatic ducts while the transit-amplifying cells occupy the distal region of the ducts. This model can account for many biological differences between cells of the proximal and distal regions, and has implications for prostatic disease formation. PMID:12082083

CD47 regulates renal tubular epithelial cell self-renewal and proliferation following renal ischemia reperfusion.

PubMed

Rogers, Natasha M; Zhang, Zheng J; Wang, Jiao-Jing; Thomson, Angus W; Isenberg, Jeffrey S

2016-08-01

Defects in renal tubular epithelial cell repair contribute to renal ischemia reperfusion injury, cause acute kidney damage, and promote chronic renal disease. The matricellular protein thrombospondin-1 and its receptor CD47 are involved in experimental renal ischemia reperfusion injury, although the role of this interaction in renal recovery is unknown. We found upregulation of self-renewal genes (transcription factors Oct4, Sox2, Klf4 and cMyc) in the kidney of CD47(-/-) mice after ischemia reperfusion injury. Wild-type animals had minimal self-renewal gene expression, both before and after injury. Suggestive of cell autonomy, CD47(-/-) renal tubular epithelial cells were found to increase expression of the self-renewal genes. This correlated with enhanced proliferative capacity compared with cells from wild-type mice. Exogenous thrombospondin-1 inhibited self-renewal gene expression in renal tubular epithelial cells from wild-type but not CD47(-/-) mice, and this was associated with decreased proliferation. Treatment of renal tubular epithelial cells with a CD47 blocking antibody or CD47-targeting small interfering RNA increased expression of some self-renewal transcription factors and promoted cell proliferation. In a syngeneic kidney transplant model, treatment with a CD47 blocking antibody increased self-renewal transcription factor expression, decreased tissue damage, and improved renal function compared with that in control mice. Thus, thrombospondin-1 via CD47 inhibits renal tubular epithelial cell recovery after ischemia reperfusion injury through inhibition of proliferation/self-renewal. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Characterization of rabbit limbal epithelial side population cells using RNA sequencing and single-cell qRT-PCR.

PubMed

Kameishi, Sumako; Umemoto, Terumasa; Matsuzaki, Yu; Fujita, Masako; Okano, Teruo; Kato, Takashi; Yamato, Masayuki

2016-05-06

Corneal epithelial stem cells reside in the limbus, a transitional zone between the cornea and conjunctiva, and are essential for maintaining homeostasis in the corneal epithelium. Although our previous studies demonstrated that rabbit limbal epithelial side population (SP) cells exhibit stem cell-like phenotypes with Hoechst 33342 staining, the different characteristics and/or populations of these cells remain unclear. Therefore, in this study, we determined the gene expression profiles of limbal epithelial SP cells by RNA sequencing using not only present public databases but also contigs that were created by de novo transcriptome assembly as references for mapping. Our transcriptome data indicated that limbal epithelial SP cells exhibited a stem cell-like phenotype compared with non-SP cells. Importantly, gene ontology analysis following RNA sequencing demonstrated that limbal epithelial SP cells exhibited significantly enhanced expression of mesenchymal/endothelial cell markers rather than epithelial cell markers. Furthermore, single-cell quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) demonstrated that the limbal epithelial SP population consisted of at least two immature cell populations with endothelial- or mesenchymal-like phenotypes. Therefore, our present results may propose the presence of a novel population of corneal epithelial stem cells distinct from conventional epithelial stem cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Nlrp9b inflammasome restricts rotavirus infection in intestinal epithelial cells.

PubMed

Zhu, Shu; Ding, Siyuan; Wang, Penghua; Wei, Zheng; Pan, Wen; Palm, Noah W; Yang, Yi; Yu, Hua; Li, Hua-Bing; Wang, Geng; Lei, Xuqiu; de Zoete, Marcel R; Zhao, Jun; Zheng, Yunjiang; Chen, Haiwei; Zhao, Yujiao; Jurado, Kellie A; Feng, Ningguo; Shan, Liang; Kluger, Yuval; Lu, Jun; Abraham, Clara; Fikrig, Erol; Greenberg, Harry B; Flavell, Richard A

2017-06-29

Rotavirus, a leading cause of severe gastroenteritis and diarrhoea in young children, accounts for around 215,000 deaths annually worldwide. Rotavirus specifically infects the intestinal epithelial cells in the host small intestine and has evolved strategies to antagonize interferon and NF-κB signalling, raising the question as to whether other host factors participate in antiviral responses in intestinal mucosa. The mechanism by which enteric viruses are sensed and restricted in vivo, especially by NOD-like receptor (NLR) inflammasomes, is largely unknown. Here we uncover and mechanistically characterize the NLR Nlrp9b that is specifically expressed in intestinal epithelial cells and restricts rotavirus infection. Our data show that, via RNA helicase Dhx9, Nlrp9b recognizes short double-stranded RNA stretches and forms inflammasome complexes with the adaptor proteins Asc and caspase-1 to promote the maturation of interleukin (Il)-18 and gasdermin D (Gsdmd)-induced pyroptosis. Conditional depletion of Nlrp9b or other inflammasome components in the intestine in vivo resulted in enhanced susceptibility of mice to rotavirus replication. Our study highlights an important innate immune signalling pathway that functions in intestinal epithelial cells and may present useful targets in the modulation of host defences against viral pathogens.

Nlrp9b inflammasome restricts rotavirus infection in intestinal epithelial cells

PubMed Central

Zhu, Shu; Ding, Siyuan; Wang, Penghua; Wei, Zheng; Pan, Wen; Palm, Noah W; Yang, Yi; Yu, Hua; Li, Hua-Bing; Wang, Geng; Lei, Xuqiu; de Zoete, Marcel R.; Zhao, Jun; Zheng, Yunjiang; Chen, Haiwei; Zhao, Yujiao; Jurado, Kellie A.; Feng, Ningguo; Shan, Liang; Kluger, Yuval; Lu, Jun; Abraham, Clara; Fikrig, Erol; Greenberg, Harry B.; Flavell, Richard A.

2018-01-01

Rotavirus, a leading cause of severe gastroenteritis and diarrhoea in young children, accounts for around 215,000 deaths annually worldwide1. Rotavirus specifically infects the intestinal epithelial cells in the host small intestine and has evolved strategies to antagonize interferon and NF-κB signalling2–5, raising the question as to whether other host factors participate in antiviral responses in intestinal mucosa. The mechanism by which enteric viruses are sensed and restricted in vivo, especially by NOD-like receptor (NLR) inflammasomes, is largely unknown. Here we uncover and mechanistically characterize the NLR Nlrp9b that is specifically expressed in intestinal epithelial cells and restricts rotavirus infection. Our data show that, via RNA helicase Dhx9, Nlrp9b recognizes short double-stranded RNA stretches and forms inflammasome complexes with the adaptor proteins Asc and caspase-1 to promote the maturation of interleukin (Il)-18 and gasdermin D (Gsdmd)-induced pyroptosis. Conditional depletion of Nlrp9b or other inflammasome components in the intestine in vivo resulted in enhanced susceptibility of mice to rotavirus replication. Our study highlights an important innate immune signalling pathway that functions in intestinal epithelial cells and may present useful targets in the modulation of host defences against viral pathogens. PMID:28636595

Targeting the Metabolic Reprogramming That Controls Epithelial-to-Mesenchymal Transition in Aggressive Tumors

PubMed Central

Morandi, Andrea; Taddei, Maria Letizia; Chiarugi, Paola; Giannoni, Elisa

2017-01-01

The epithelial-to-mesenchymal transition (EMT) process allows the trans-differentiation of a cell with epithelial features into a cell with mesenchymal characteristics. This process has been reported to be a key priming event for tumor development and therefore EMT activation is now considered an established trait of malignancy. The transcriptional and epigenetic reprogramming that governs EMT has been extensively characterized and reviewed in the last decade. However, increasing evidence demonstrates a correlation between metabolic reprogramming and EMT execution. The aim of the current review is to gather the recent findings that illustrate this correlation to help deciphering whether metabolic changes are causative or just a bystander effect of EMT activation. The review is divided accordingly to the catabolic and anabolic pathways that characterize carbohydrate, aminoacid, and lipid metabolism. Moreover, at the end of each part, we have discussed a series of potential metabolic targets involved in EMT promotion and execution for which drugs are either available or that could be further investigated for therapeutic intervention. PMID:28352611

Continuous activation of Nrf2 and its target antioxidant enzymes leads to arsenite-induced malignant transformation of human bronchial epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Xu; Wang, Dapeng; Department of Toxicology, School of Public Health, Guizhou Medical University, Guiyang, Guizhou

Long-term exposure to arsenite leads to human lung cancer, but the underlying mechanisms of carcinogenesis remain obscure. The transcription factor of nuclear factor-erythroid-2 p45-related factor (Nrf2)-mediated antioxidant response represents a critical cellular defense mechanism and protection against various diseases. Paradoxically, emerging data suggest that the constitutive activation of Nrf2 is associated with cancer development, progression and chemotherapy resistance. However, the role of Nrf2 in the occurrence of cancer induced by long-term arsenite exposure remains to be fully understood. By establishing transformed human bronchial epithelial (HBE) cells via chronic low-dose arsenite treatment, we showed that, in acquiring this malignant phenotype, continuousmore » low level of ROS and sustained enhancement of Nrf2 and its target antioxidant enzyme levels were observed in the later-stage of arsenite-induced cell transformation. The downregulation of Keap1 level may be responsible for the over-activation of Nrf2 and its target enzymes. To validate these observations, Nrf2 was knocked down in arsenite-transformed HBE cells by SiRNA transfection, and the levels of Nrf2 and its target antioxidant enzymes, ROS, cell proliferation, migration, and colony formation were determined following these treatments. Results showed that blocked Nrf2 expression significantly reduced Nrf2 and its target antioxidant enzyme levels, restored ROS levels, and eventually suppressed cell proliferation, migration, and colony formation of the transformed cells. In summary, the results of the study strongly suggested that the continuous activation of Nrf2 and its target antioxidant enzymes led to the over-depletion of intracellular ROS levels, which contributed to arsenite-induced HBE cell transformation. - Highlights: • Low level, long term arsenite exposure induces malignant transformation in vitro. • Long term arsenite exposure reduces ROS and MDA levels. • Long term

Single-cell RNA sequencing identifies diverse roles of epithelial cells in idiopathic pulmonary fibrosis

PubMed Central

Mizuno, Takako; Sridharan, Anusha; Du, Yina; Guo, Minzhe; Wikenheiser-Brokamp, Kathryn A.; Perl, Anne-Karina T.; Funari, Vincent A.; Gokey, Jason J.; Stripp, Barry R.; Whitsett, Jeffrey A.

2016-01-01

Idiopathic pulmonary fibrosis (IPF) is a lethal interstitial lung disease characterized by airway remodeling, inflammation, alveolar destruction, and fibrosis. We utilized single-cell RNA sequencing (scRNA-seq) to identify epithelial cell types and associated biological processes involved in the pathogenesis of IPF. Transcriptomic analysis of normal human lung epithelial cells defined gene expression patterns associated with highly differentiated alveolar type 2 (AT2) cells, indicated by enrichment of RNAs critical for surfactant homeostasis. In contrast, scRNA-seq of IPF cells identified 3 distinct subsets of epithelial cell types with characteristics of conducting airway basal and goblet cells and an additional atypical transitional cell that contributes to pathological processes in IPF. Individual IPF cells frequently coexpressed alveolar type 1 (AT1), AT2, and conducting airway selective markers, demonstrating “indeterminate” states of differentiation not seen in normal lung development. Pathway analysis predicted aberrant activation of canonical signaling via TGF-β, HIPPO/YAP, P53, WNT, and AKT/PI3K. Immunofluorescence confocal microscopy identified the disruption of alveolar structure and loss of the normal proximal-peripheral differentiation of pulmonary epithelial cells. scRNA-seq analyses identified loss of normal epithelial cell identities and unique contributions of epithelial cells to the pathogenesis of IPF. The present study provides a rich data source to further explore lung health and disease. PMID:27942595

Protons Sensitize Epithelial Cells to Mesenchymal Transition

PubMed Central

Wang, Minli; Hada, Megumi; Saha, Janapriya; Sridharan, Deepa M.; Pluth, Janice M.; Cucinotta, Francis A.

2012-01-01

Proton radiotherapy has gained more favor among oncologists as a treatment option for localized and deep-seated tumors. In addition, protons are a major constituent of the space radiation astronauts receive during space flights. The potential for these exposures to lead to, or enhance cancer risk has not been well studied. Our objective is to study the biological effects of low energy protons on epithelial cells and its propensity to enhance transforming growth factor beta 1 (TGFβ1)-mediated epithelial-mesenchymal transition (EMT), a process occurring during tumor progression and critical for invasion and metastasis. Non-transformed mink lung epithelial cells (Mv1Lu) and hTERT- immortalized human esophageal epithelial cells (EPC) were used in this study. EMT was identified by alterations in cell morphology, EMT-related gene expression changes determined using real-time PCR, and EMT changes in specific cellular markers detected by immunostaining and western blotting. Although TGFβ1 treatment alone is able to induce EMT in both Mv1Lu and EPC cells, low energy protons (5 MeV) at doses as low as 0.1 Gy can enhance TGFβ1 induced EMT. Protons alone can also induce a mild induction of EMT. SD208, a potent TGFβ Receptor 1 (TGFβR1) kinase inhibitor, can efficiently block TGFβ1/Smad signaling and attenuate EMT induction. We suggest a model for EMT after proton irradiation in normal and cancerous tissue based on our results that showed that low and high doses of protons can sensitize normal human epithelial cells to mesenchymal transition, more prominently in the presence of TGFβ1, but also in the absence of TGFβ1. PMID:22844446

Protons sensitize epithelial cells to mesenchymal transition.

PubMed

Wang, Minli; Hada, Megumi; Saha, Janapriya; Sridharan, Deepa M; Pluth, Janice M; Cucinotta, Francis A

2012-01-01

Proton radiotherapy has gained more favor among oncologists as a treatment option for localized and deep-seated tumors. In addition, protons are a major constituent of the space radiation astronauts receive during space flights. The potential for these exposures to lead to, or enhance cancer risk has not been well studied. Our objective is to study the biological effects of low energy protons on epithelial cells and its propensity to enhance transforming growth factor beta 1 (TGFβ1)-mediated epithelial-mesenchymal transition (EMT), a process occurring during tumor progression and critical for invasion and metastasis. Non-transformed mink lung epithelial cells (Mv1Lu) and hTERT- immortalized human esophageal epithelial cells (EPC) were used in this study. EMT was identified by alterations in cell morphology, EMT-related gene expression changes determined using real-time PCR, and EMT changes in specific cellular markers detected by immunostaining and western blotting. Although TGFβ1 treatment alone is able to induce EMT in both Mv1Lu and EPC cells, low energy protons (5 MeV) at doses as low as 0.1 Gy can enhance TGFβ1 induced EMT. Protons alone can also induce a mild induction of EMT. SD208, a potent TGFβ Receptor 1 (TGFβR1) kinase inhibitor, can efficiently block TGFβ1/Smad signaling and attenuate EMT induction. We suggest a model for EMT after proton irradiation in normal and cancerous tissue based on our results that showed that low and high doses of protons can sensitize normal human epithelial cells to mesenchymal transition, more prominently in the presence of TGFβ1, but also in the absence of TGFβ1.

Conditional immortalization of human thyroid epithelial cells: a tool for analysis of oncogene action.

PubMed Central

Wynford-Thomas, D; Bond, J A; Wyllie, F S; Burns, J S; Williams, E D; Jones, T; Sheer, D; Lemoine, N R

1990-01-01

To overcome the difficulty of assessing oncogene action in human epithelial cell types, such as thyroid, which have limited proliferative potential in culture, we have explored the use of temperature-sensitive (ts) mutants of simian virus 40 (SV40) early region to create conditionally immortalized epithelial cell lines. Normal primary cultures of human thyroid follicular cells were transfected with a plasmid containing the SV40 early region from mutant tsA58. Expanding epithelial colonies were observed after 2 to 3 months, all of which grew to greater than 200 population doublings without crisis. All showed tight temperature dependence for growth. After switch-up to the restrictive temperature (40.5 degrees C), no further increase in cell number was seen after 1 to 2 days. However, DNA synthesis declined much more slowly; the dissociation from cell division led to marked polyploidy. Viability was maintained for up to 2 weeks. Introduction of an inducible mutant ras gene into ts thyroid cells led, as expected, to morphological transformation at the permissive temperature when ras was induced. Interestingly, this was associated with a marked reduction in net growth rate. At the restrictive temperature, induction of mutant ras caused rapid cell death. These results demonstrate the utility of a ts SV40 mutant to permit the study of oncogene action in an otherwise nonproliferative target cell and reveal important differences in the interaction between ras and SV40 T in these epithelial cells compared with previously studied cell types. Images PMID:1697930

Cytomegalovirus Virions Shed in Urine Have a Reversible Block to Epithelial Cell Entry and Are Highly Resistant to Antibody Neutralization

PubMed Central

Cui, Xiaohong; Adler, Stuart P.; Schleiss, Mark R.; Demmler Harrison, Gail J.

2017-01-01

ABSTRACT Cytomegalovirus (CMV) causes sensorineural hearing loss and developmental disabilities in newborns when infections are acquired in utero. Pregnant women may acquire CMV from oral exposure to CMV in urine or saliva from young children. Neutralizing antibodies in maternal saliva have the potential to prevent maternal infection and, in turn, fetal infection. As CMV uses different viral glycoprotein complexes to enter different cell types, the first cells to be infected in the oral cavity could determine the type of antibodies needed to disrupt oral transmission. Antibodies targeting the pentameric complex (PC) should block CMV entry into epithelial cells but not into fibroblasts or Langerhans cells (which do not require the PC for entry), while antibodies targeting glycoprotein complexes gB or gH/gL would be needed to block entry into fibroblasts, Langerhans cells, or other cell types. To assess the potential for antibodies to disrupt oral acquisition, CMV from culture-positive urine samples (uCMV) was used to study cell tropisms and sensitivity to antibody neutralization. uCMV entered epithelial cells poorly compared with the entry into fibroblasts. CMV-hyperimmune globulin or monoclonal antibodies targeting gB, gH/gL, or the PC were incapable of blocking the entry of uCMV into either fibroblasts or epithelial cells. Both phenotypes were lost after one passage in cultured fibroblasts, suggestive of a nongenetic mechanism. These results suggest that uCMV virions have a reversible block to epithelial cell entry. Antibodies may be ineffective in preventing maternal oral CMV acquisition but may limit viral spread in blood or tissues, thereby reducing or preventing fetal infection and disease. PMID:28404573

Corynebacterium diphtheriae employs specific minor pilins to target human pharyngeal epithelial cells

PubMed Central

Mandlik, Anjali; Swierczynski, Arlene; Das, Asis; Ton-That, Hung

2010-01-01

Summary Adherence to host tissues mediated by pili is pivotal in the establishment of infection by many bacterial pathogens. Corynebacterium diphtheriae assembles on its surface three distinct pilus structures. The function and the mechanism of how various pili mediate adherence, however, have remained poorly understood. Here we show that the SpaA-type pilus is sufficient for the specific adherence of corynebacteria to human pharyngeal epithelial cells. The deletion of the spaA gene, which encodes the major pilin forming the pilus shaft, abolishes pilus assembly but not adherence to pharyngeal cells. In contrast, adherence is greatly diminished when either minor pilin SpaB or SpaC is absent. Antibodies directed against either SpaB or SpaC block bacterial adherence. Consistent with a direct role of the minor pilins, latex beads coated with SpaB or SpaC protein bind specifically to pharyngeal cells. Therefore, tissue tropism of corynebacteria for pharyngeal cells is governed by specific minor pilins. Importantly, immunoelectron microscopy and immunofluorescence studies reveal clusters of minor pilins that are anchored to cell surface in the absence of a pilus shaft. Thus, the minor pilins may also be cell wall anchored in addition to their incorporation into pilus structures that could facilitate tight binding to host cells during bacterial infection. PMID:17376076

Phenotypic high-throughput screening elucidates target pathway in breast cancer stem cell-like cells.

PubMed

Carmody, Leigh C; Germain, Andrew R; VerPlank, Lynn; Nag, Partha P; Muñoz, Benito; Perez, Jose R; Palmer, Michelle A J

2012-10-01

Cancer stem cells (CSCs) are resistant to standard cancer treatments and are likely responsible for cancer recurrence, but few therapies target this subpopulation. Due to the difficulty in propagating CSCs outside of the tumor environment, previous work identified CSC-like cells by inducing human breast epithelial cells into an epithelial-to-mesenchymal transdifferentiated state (HMLE_sh_ECad). A phenotypic screen was conducted against HMLE_sh_ECad with 300 718 compounds from the Molecular Libraries Small Molecule Repository to identify selective inhibitors of CSC growth. The screen yielded 2244 hits that were evaluated for toxicity and selectivity toward an isogenic control cell line. An acyl hydrazone scaffold emerged as a potent and selective scaffold targeting HMLE_sh_ECad. Fifty-three analogues were acquired and tested; compounds ranged in potency from 790 nM to inactive against HMLE_sh_ECad. Of the analogues, ML239 was best-in-class with an IC(50)= 1.18 µM against HMLE_sh_ECad, demonstrated a >23-fold selectivity over the control line, and was toxic to another CSC-like line, HMLE_shTwist, and a breast carcinoma cell line, MDA-MB-231. Gene expression studies conducted with ML239-treated cells showed altered gene expression in the NF-κB pathway in the HMLE_sh_ECad line but not in the isogenic control line. Future studies will be directed toward the identification of ML239 target(s).

Sequestration of human cytomegalovirus by human renal and mammary epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Twite, Nicolas; Andrei, Graciela; Kummert, Caroline

2014-07-15

Urine and breast milk represent the main routes of human cytomegalovirus (HCMV) transmission but the contribution of renal and mammary epithelial cells to viral excretion remains unclear. We observed that kidney and mammary epithelial cells were permissive to HCMV infection and expressed immediate early, early and late antigens within 72 h of infection. During the first 24 h after infection, high titers of infectious virus were measured associated to the cells and in culture supernatants, independently of de novo synthesis of virus progeny. This phenomenon was not observed in HCMV-infected fibroblasts and suggested the sequestration and the release of HCMVmore » by epithelial cells. This hypothesis was supported by confocal and electron microscopy analyses. The sequestration and progressive release of HCMV by kidney and mammary epithelial cells may play an important role in the excretion of the virus in urine and breast milk and may thereby contribute to HCMV transmission. - Highlights: • Primary renal and mammary epithelial cells are permissive to HCMV infection. • HCMV is sequestered by epithelial cells and this phenomenon does not require viral replication. • HCMV sequestration by epithelial cells is reduced by antibodies and IFN-γ.« less

Cadherin-23 Mediates Heterotypic Cell-Cell Adhesion between Breast Cancer Epithelial Cells and Fibroblasts

PubMed Central

Apostolopoulou, Maria; Ligon, Lee

2012-01-01

In the early stages of breast cancer metastasis, epithelial cells penetrate the basement membrane and invade the surrounding stroma, where they encounter fibroblasts. Paracrine signaling between fibroblasts and epithelial tumor cells contributes to the metastatic cascade, but little is known about the role of adhesive contacts between these two cell types in metastasis. Here we show that MCF-7 breast cancer epithelial cells and normal breast fibroblasts form heterotypic adhesions when grown together in co-culture, as evidenced by adhesion assays. PCR and immunoblotting show that both cell types express multiple members of the cadherin superfamily, including the atypical cadherin, cadherin-23, when grown in isolation and in co-culture. Immunocytochemistry experiments show that cadherin-23 localizes to homotypic adhesions between MCF-7 cells and also to heterotypic adhesions between the epithelial cells and fibroblasts, and antibody inhibition and RNAi experiments show that cadherin-23 plays a role in mediating these adhesive interactions. Finally, we show that cadherin-23 is upregulated in breast cancer tissue samples, and we hypothesize that heterotypic adhesions mediated by this atypical cadherin may play a role in the early stages of metastasis. PMID:22413011

Lateral adhesion drives reintegration of misplaced cells into epithelial monolayers.

PubMed

Bergstralh, Dan T; Lovegrove, Holly E; St Johnston, Daniel

2015-11-01

Cells in simple epithelia orient their mitotic spindles in the plane of the epithelium so that both daughter cells are born within the epithelial sheet. This is assumed to be important to maintain epithelial integrity and prevent hyperplasia, because misaligned divisions give rise to cells outside the epithelium. Here we test this assumption in three types of Drosophila epithelium; the cuboidal follicle epithelium, the columnar early embryonic ectoderm, and the pseudostratified neuroepithelium. Ectopic expression of Inscuteable in these tissues reorients mitotic spindles, resulting in one daughter cell being born outside the epithelial layer. Live imaging reveals that these misplaced cells reintegrate into the tissue. Reducing the levels of the lateral homophilic adhesion molecules Neuroglian or Fasciclin 2 disrupts reintegration, giving rise to extra-epithelial cells, whereas disruption of adherens junctions has no effect. Thus, the reinsertion of misplaced cells seems to be driven by lateral adhesion, which pulls cells born outside the epithelial layer back into it. Our findings reveal a robust mechanism that protects epithelia against the consequences of misoriented divisions.

Fibrin glue inhibits migration of ocular surface epithelial cells

PubMed Central

Yeung, A M; Faraj, L A; McIntosh, O D; Dhillon, V K; Dua, H S

2016-01-01

Purpose Fibrin glue has been used successfully in numerous ophthalmic surgical procedures. Recently, fibrin glue has been used in limbal stem cell transplantation to reduce both operative time and to negate the need for sutures. The aim of this study was to determine the effects of fibrin glue on epithelial cell migration in vitro. Methods Corneoscleral rims were split to retain the epithelial layer, Bowman's layer, and anterior stroma. Rims were cut into eight equal-sized pieces and were placed directly on culture plates or affixed with fibrin glue. Rims were maintained in culture for 25 days and epithelial cell growth was monitored. Cells were photographed to measure area or growth and immunofluorescence staining of explants for fibrin was performed. Results Explants that were glued demonstrated significantly delayed epithelial cell growth and migration as compared with explants without glue. By day 16, all fibrin glue had dissolved and coincided with onset of cell growth from glued explants. Cell growth commenced between days 3 and 4 for control explants without glue and around days 14–16 for explants with fibrin glue. Conclusions Fibrin glue delays epithelial cell migration by acting as a physical barrier and can potentially interfere with explant-derived limbal epithelial cell migration on to the corneal surface. We propose that glue should be used to attach the conjunctival frill of the limbal explant but care should be taken to ensure that the glue does not wrap around the explant if used to secure the explant as well. Strategic use of glue, to attach the recessed conjunctiva, can be advantageous in delaying conjunctival cell migration and reducing the need for sequential sector conjunctival epitheliectomy. PMID:27367746

Targeting palmitoyl acyltransferase ZDHHC21 improves gut epithelial barrier dysfunction resulting from burn-induced systemic inflammation.

PubMed

Haines, R J; Wang, C Y; Yang, C G Y; Eitnier, R A; Wang, F; Wu, M H

2017-12-01

Clinical studies in burn patients demonstrate a close association between leaky guts and increased incidence or severity of sepsis and other complications. Severe thermal injury triggers intestinal inflammation that contributes to intestinal epithelial hyperpermeability, which exacerbates systemic response leading to multiple organ failure and sepsis. In this study, we identified a significant function of a particular palmitoyl acyltransferase, zinc finger DHHC domain-containing protein-21 (ZDHHC21), in mediating signaling events required for gut hyperpermeability induced by inflammation. Using quantitative PCR, we show that ZDHHC21 mRNA production was enhanced twofold when intestinal epithelial cells were treated with TNF-α-IFN-γ in vitro. In addition, pharmacological targeting of palmitoyl acyltransferases with 2-bromopalmitate (2-BP) showed significant improvement in TNF-α-IFN-γ-mediated epithelial barrier dysfunction by using electric cell-substrate impedance-sensing assays, as well as FITC-labeled dextran permeability assays. Using acyl-biotin exchange assay and click chemistry, we show that TNF-α-IFN-γ treatment of intestinal epithelial cells results in enhanced detection of total palmitoylated proteins and this response is inhibited by 2-BP. Using ZDHHC21-deficient mice or wild-type mice treated with 2-BP, we showed that mice with impaired ZDHHC21 expression or pharmacological inhibition resulted in attenuated intestinal barrier dysfunction caused by thermal injury. Moreover, hematoxylin and eosin staining of the small intestine, as well as transmission electron microscopy, showed that mice with genetic interruption of ZDHHC21 had attenuated villus structure disorganization associated with thermal injury-induced intestinal barrier damage. Taken together, these results suggest an important role of ZDHHC21 in mediating gut hyperpermeability resulting from thermal injury. NEW & NOTEWORTHY Increased mucosal permeability in the gut is one of the major

Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montesano, Roberto; Sarkoezi, Rita; Schramek, Herbert

2008-09-12

Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hithertomore » unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.« less

Mechanobiology in Lung Epithelial Cells: Measurements, Perturbations, and Responses

PubMed Central

Waters, Christopher M.; Roan, Esra; Navajas, Daniel

2015-01-01

Epithelial cells of the lung are located at the interface between the environment and the organism and serve many important functions including barrier protection, fluid balance, clearance of particulate, initiation of immune responses, mucus and surfactant production, and repair following injury. Because of the complex structure of the lung and its cyclic deformation during the respiratory cycle, epithelial cells are exposed to continuously varying levels of mechanical stresses. While normal lung function is maintained under these conditions, changes in mechanical stresses can have profound effects on the function of epithelial cells and therefore the function of the organ. In this review, we will describe the types of stresses and strains in the lungs, how these are transmitted, and how these may vary in human disease or animal models. Many approaches have been developed to better understand how cells sense and respond to mechanical stresses, and we will discuss these approaches and how they have been used to study lung epithelial cells in culture. Understanding how cells sense and respond to changes in mechanical stresses will contribute to our understanding of the role of lung epithelial cells during normal function and development and how their function may change in diseases such as acute lung injury, asthma, emphysema, and fibrosis. PMID:23728969

In vitro differentiation of human tooth germ stem cells into endothelial- and epithelial-like cells.

PubMed

Doğan, Ayşegül; Demirci, Selami; Şahin, Fikrettin

2015-01-01

Current clinical techniques in dental practice include stem cell and tissue engineering applications. Dental stem cells are promising primary cell source for mainly tooth tissue engineering. Interaction of mesenchymal stem cell with epithelial and endothelial cells is strictly required for an intact tooth morphogenesis. Therefore, it is important to investigate whether human tooth germ stem cells (hTGSCs) derived from wisdom tooth are suitable for endothelial and epithelial cell transformation in dental tissue regeneration approaches. Differentiation into endothelial and epithelial cell lineages were mimicked under defined conditions, confirmed by real time PCR, western blotting and immunocytochemical analysis by qualitative and quantitative methods. HUVECs and HaCaT cells were used as positive controls for the endothelial and epithelial differentiation assays, respectively. Immunocytochemical and western blotting analysis revealed that terminally differentiated cells expressed cell-lineage markers including CD31, VEGFR2, VE-Cadherin, vWF (endothelial cell markers), and cytokeratin (CK)-17, CK-19, EpCaM, vimentin (epithelial cell markers) in significant levels with respect to undifferentiated control cells. Moreover, high expression levels of VEGFR1, VEGFR2, VEGF, CK-18, and CK-19 genes were detected in differentiated endothelial and epithelial-like cells. Endothelial-like cells derived from hTGSCs were cultured on Matrigel, tube-like structure formations were followed as an indication for functional endothelial differentiation. hTGSCs successfully differentiate into various cell types with a broad range of functional abilities using an in vitro approach. These findings suggest that hTGSCs may serve a potential stem cell source for tissue engineering and cell therapy of epithelial and endothelial tissue. © 2014 International Federation for Cell Biology.

Cigarette smoke suppresses Bik to cause epithelial cell hyperplasia and mucous cell metaplasia.

PubMed

Mebratu, Yohannes A; Schwalm, Kurt; Smith, Kevin R; Schuyler, Mark; Tesfaigzi, Yohannes

2011-06-01

Aberrant regulation of airway epithelial cell numbers in airways leads to increased mucous secretions in chronic lung diseases such as chronic bronchitis. Because the Bcl-2 family of proteins is crucial for airway epithelial homeostasis, identifying the players that reduce cigarette smoke (CS)-induced mucous cell metaplasia can help to develop effective therapies. To identify the Bcl-2 family of proteins that play a role in reducing CS-induced mucous cell metaplasia. We screened for dysregulated expression of the Bcl-2 family members. We identified Bik to be significantly reduced in bronchial brushings of patients with chronic epithelial cell hyperplasia compared with nondiseased control subjects. Reduced Bik but increased MUC5AC mRNA levels were also detected when normal human airway epithelial cells (HAECs) were exposed to CS or when autopsy tissues from former smokers with and without chronic bronchitis were compared. Similarly, exposure of C57Bl/6 mice to CS resulted in increased numbers of epithelial and mucous cells per millimeter of basal lamina, along with reduced Bik but increased Muc5ac expression, and this change was sustained even when mice were allowed to recover in filtered air for 8 weeks. Restoring Bik expression significantly suppressed CS-induced mucous cell metaplasia in differentiated primary HAEC cultures and in airways of mice in vivo. Bik blocked nuclear translocation of phospho-ERK1/2 to induce apoptosis of HAECs. The conserved Leu61 within Bik and ERK1/2 activation were essential to induce cell death in hyperplastic mucous cells. These studies show that CS suppresses Bik expression to block airway epithelia cell death and thereby increases epithelial cell hyperplasia in chronic bronchitis.

Apelin attenuates TGF-β1-induced epithelial to mesenchymal transition via activation of PKC-ε in human renal tubular epithelial cells.

PubMed

Wang, Li-Yan; Diao, Zong-Li; Zheng, Jun-Fang; Wu, Yi-Ru; Zhang, Qi-Dong; Liu, Wen-Hu

2017-10-01

Epithelial to mesenchymal transition (EMT), a process whereby fully differentiated epithelial cells transition to a mesenchymal phenotype, has been implicated in the pathogenesis of renal fibrosis. Apelin, a bioactive peptide, has recently been recognized to protect against renal profibrotic activity, but the underlying mechanism has not yet been elucidated. In this study, we investigated the regulation of EMT in the presence of apelin-13 in vitro. Expression of the mesenchymal marker alpha-smooth muscle actin (α-SMA) and the epithelial marker E-cadherin was examined by immunofluorescence and western blotting in transforming growth factor beta 1 (TGF-β1)-stimulated human proximal tubular epithelial cells. Expression of extracellular matrix, fibronectin and collagen-I was examined by quantitative real-time PCR and ELISA. F13A, an antagonist of the apelin receptor APJ, and small interfering RNA targeting protein kinase C epsilon (PKC-ε) were used to explore the relevant signaling pathways. Apelin attenuated TGF-β1-induced EMT, and inhibited the EMT-associated increase in α-SMA, loss of E-cadherin, and secretion of extracellular matrix. Moreover, apelin activated PKC-ε in tubular epithelial cells, which in turn decreased phospho-Smad2/3 levels and increased Smad-7 levels. APJ inhibition or PKC-ε deletion diminished apelin-induced modulation of Smad signaling and suppression of tubular EMT. Our findings identify a novel PKC-ε-dependent mechanism in which apelin suppresses TGF-β1-mediated activation of Smad signaling pathways and thereby inhibits tubular EMT. These results suggest that apelin may be a new agent that can suppress renal fibrosis and retard chronic kidney disease progression. Copyright © 2017 Elsevier Inc. All rights reserved.

E-Cigarette Vapor Induces an Apoptotic Response in Human Gingival Epithelial Cells Through the Caspase-3 Pathway.

PubMed

Rouabhia, Mahmoud; Park, Hyun Jin; Semlali, Abdelhabib; Zakrzewski, Andrew; Chmielewski, Witold; Chakir, Jamila

2017-06-01

Electronic cigarettes represent an increasingly significant proportion of today's consumable tobacco products. E-cigarettes contain several chemicals which may promote oral diseases. The aim of this study was to investigate the effect of e-cigarette vapor on human gingival epithelial cells. Results show that e-cigarette vapor altered the morphology of cells from small cuboidal form to large undefined shapes. Both single and multiple exposures to e-cigarette vapor led to a bulky morphology with large faint nuclei and an enlarged cytoplasm. E-cigarette vapor also increased L-lactate dehydrogenase (LDH) activity in the targeted cells. This activity was greater with repeated exposures. Furthermore, e-cigarette vapor increased apoptotic/necrotic epithelial cell percentages compared to that observed in the control. Epithelial cell apoptosis was confirmed by TUNEL assay showing that exposure to e-cigarette vapor increased apoptotic cell numbers, particularly after two and three exposures. This negative effect involved the caspase-3 pathway, the activity of which was greater with repeated exposure and which decreased following the use of caspase-3 inhibitor. The adverse effects of e-cigarette vapor on gingival epithelial cells may lead to dysregulated gingival cell function and result in oral disease. J. Cell. Physiol. 232: 1539-1547, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Distinct effects of EGFR inhibitors on epithelial- and mesenchymal-like esophageal squamous cell carcinoma cells.

PubMed

Yoshioka, Masahiro; Ohashi, Shinya; Ida, Tomomi; Nakai, Yukie; Kikuchi, Osamu; Amanuma, Yusuke; Matsubara, Junichi; Yamada, Atsushi; Miyamoto, Shin'ichi; Natsuizaka, Mitsuteru; Nakagawa, Hiroshi; Chiba, Tsutomu; Seno, Hiroshi; Muto, Manabu

2017-08-01

Epidermal growth factor receptor (EGFR) plays a pivotal role in the pathophysiology of esophageal squamous cell carcinoma (ESCC). However, the clinical effects of EGFR inhibitors on ESCC are controversial. This study sought to identify the factors determining the therapeutic efficacy of EGFR inhibitors in ESCC cells. Immortalized-human esophageal epithelial cells (EPC2-hTERT), transformed-human esophageal epithelial cells (T-Epi and T-Mes), and ESCC cells (TE-1, TE-5, TE-8, TE-11, TE-11R, and HCE4) were treated with the EGFR inhibitors erlotinib or cetuximab. Inhibitory effects on cell growth were assessed by cell counting or cell-cycle analysis. The expression levels of genes and proteins such as involucrin and cytokeratin13 (a squamous differentiation marker), E-cadherin, and vimentin were evaluated by real-time polymerase chain reaction or western blotting. To examine whether mesenchymal phenotype influenced the effects of EGFR inhibitors, we treated T-Epi cells with TGF-β1 to establish a mesenchymal phenotype (mesenchymal T-Epi cells). We then compared the effects of EGFR inhibitors on parental T-Epi cells and mesenchymal T-Epi cells. TE-8 (mesenchymal-like ESCC cells)- or TE-11R (epithelial-like ESCC cells)-derived xenograft tumors in mice were treated with cetuximab, and the antitumor effects of EGFR inhibitors were evaluated. Cells were classified as epithelial-like or mesenchymal-like phenotypes, determined by the expression levels of E-cadherin and vimentin. Both erlotinib and cetuximab reduced cell growth and the ratio of cells in cell-cycle S phase in epithelial-like but not mesenchymal-like cells. Additionally, EGFR inhibitors induced squamous cell differentiation (defined as increased expression of involucrin and cytokeratin13) in epithelial-like but not mesenchymal-like cells. We found that EGFR inhibitors did not suppress the phosphorylation of EGFR in mesenchymal-like cells, while EGFR dephosphorylation was observed after treatment with EGFR

SERCA2 Regulates Non-CF and CF Airway Epithelial Cell Response to Ozone

PubMed Central

Ahmad, Shama; Nichols, David P.; Strand, Matthew; Rancourt, Raymond C.; Randell, Scott H.; White, Carl W.; Ahmad, Aftab

2011-01-01

Calcium mobilization can regulate a wide range of essential functions of respiratory epithelium, including ion transport, ciliary beat frequency, and secretion of mucus, all of which are modified in cystic fibrosis (CF). SERCA2, an important controller of calcium signaling, is deficient in CF epithelium. We conducted this study to determine whether SERCA2 deficiency can modulate airway epithelial responses to environmental oxidants such as ozone. This could contribute to the pathogenesis of pulmonary exacerbations, which are important and frequent clinical events in CF. To address this, we used air-liquid interface (ALI) cultures of non-CF and CF cell lines, as well as differentiated cultures of cells derived from non-CF and CF patients. We found that ozone exposure caused enhanced membrane damage, mitochondrial dysfunction and apoptotic cell death in CF airway epithelial cell lines relative to non-CF. Ozone exposure caused increased proinflammatory cytokine production in CF airway epithelial cell lines. Elevated proinflammatory cytokine production also was observed in shRNA-mediated SERCA2 knockdown cells. Overexpression of SERCA2 reversed ozone-induced proinflammatory cytokine production. Ozone-induced proinflammatory cytokine production was NF-κB- dependent. In a stable NF-κB reporter cell line, SERCA2 inhibition and knockdown both upregulated cytomix-induced NF-κB activity, indicating importance of SERCA2 in modulating NF-κB activity. In this system, increased NF-κB activity was also accompanied by increased IL-8 production. Ozone also induced NF-κB activity and IL-8 release, an effect that was greater in SERCA2-silenced NF-κB-reporter cells. SERCA2 overexpression reversed cytomix-induced increased IL-8 release and total nuclear p65 in CFTR-deficient (16HBE-AS) cells. These studies suggest that SERCA2 is an important regulator of the proinflammatory response of airway epithelial cells and could be a potential therapeutic target. PMID:22096575

MiR-30c regulates cisplatin-induced apoptosis of renal tubular epithelial cells by targeting Bnip3L and Hspa5

PubMed Central

Du, Bin; Dai, Xiao-meng; Li, Shuang; Qi, Guo-long; Cao, Guang-xu; Zhong, Ying; Yin, Pei-di; Yang, Xue-song

2017-01-01

As a common anticancer drug, cisplatin has been widely used for treating tumors in the clinic. However, its side effects, especially its nephrotoxicity, noticeably restrict the application of cisplatin. Therefore, it is imperative to investigate the mechanism of renal injury and explore the corresponding remedies. In this study, we showed the phenotypes of the renal tubules and epithelial cell death as well as elevated cleaved-caspase3- and TUNEL-positive cells in rats intraperitoneally injected with cisplatin. Similar cisplatin-induced cell apoptosis was found in HK-2 and NRK-52E cells exposed to cisplatin as well. In both models of cisplatin-induced apoptosis in vivo and in vitro, quantitative PCR data displayed reductions in miR-30a-e expression levels, indicating that miR-30 might be involved in regulating cisplatin-induced cell apoptosis. This was further confirmed when the effects of cisplatin-induced cell apoptosis were found to be closely correlated with alterations in miR-30c expression, which were manipulated by transfection of either the miR-30c mimic or miR-30c inhibitor in HK-2 and NRK-52E cells. Using bioinformatics tools, including TargetScan and a gene expression database (Gene Expression Omnibus), Adrb1, Bnip3L, Hspa5 and MAP3K12 were predicted to be putative target genes of miR-30c in cisplatin-induced apoptosis. Subsequently, Bnip3L and Hspa5 were confirmed to be the target genes after determining the expression of these putative genes following manipulation of miR-30c expression levels in HK-2 cells. Taken together, our current experiments reveal that miR-30c is certainly involved in regulating the renal tubular cell apoptosis induced by cisplatin, which might supply a new strategy to minimize cisplatin-induced nephrotoxicity. PMID:28796263

MiR-30c regulates cisplatin-induced apoptosis of renal tubular epithelial cells by targeting Bnip3L and Hspa5.

PubMed

Du, Bin; Dai, Xiao-Meng; Li, Shuang; Qi, Guo-Long; Cao, Guang-Xu; Zhong, Ying; Yin, Pei-di; Yang, Xue-Song

2017-08-10

As a common anticancer drug, cisplatin has been widely used for treating tumors in the clinic. However, its side effects, especially its nephrotoxicity, noticeably restrict the application of cisplatin. Therefore, it is imperative to investigate the mechanism of renal injury and explore the corresponding remedies. In this study, we showed the phenotypes of the renal tubules and epithelial cell death as well as elevated cleaved-caspase3- and TUNEL-positive cells in rats intraperitoneally injected with cisplatin. Similar cisplatin-induced cell apoptosis was found in HK-2 and NRK-52E cells exposed to cisplatin as well. In both models of cisplatin-induced apoptosis in vivo and in vitro, quantitative PCR data displayed reductions in miR-30a-e expression levels, indicating that miR-30 might be involved in regulating cisplatin-induced cell apoptosis. This was further confirmed when the effects of cisplatin-induced cell apoptosis were found to be closely correlated with alterations in miR-30c expression, which were manipulated by transfection of either the miR-30c mimic or miR-30c inhibitor in HK-2 and NRK-52E cells. Using bioinformatics tools, including TargetScan and a gene expression database (Gene Expression Omnibus), Adrb1, Bnip3L, Hspa5 and MAP3K12 were predicted to be putative target genes of miR-30c in cisplatin-induced apoptosis. Subsequently, Bnip3L and Hspa5 were confirmed to be the target genes after determining the expression of these putative genes following manipulation of miR-30c expression levels in HK-2 cells. Taken together, our current experiments reveal that miR-30c is certainly involved in regulating the renal tubular cell apoptosis induced by cisplatin, which might supply a new strategy to minimize cisplatin-induced nephrotoxicity.

Comparison of para-aminophenol cytotoxicity in rat renal epithelial cells and hepatocytes.

PubMed

Li, Ying; Bentzley, Catherine M; Tarloff, Joan B

2005-04-01

Several chemicals, including para-aminophenol (PAP), produce kidney damage in the absence of hepatic damage. Selective nephrotoxicity may be related to the ability of the kidney to reabsorb filtered water, thereby raising the intraluminal concentration of toxicants and exposing tubular epithelial cells to higher concentrations than would be present in other tissues. The present experiments tested the hypothesis that hepatocytes and renal epithelial cells exposed to equivalent concentrations of PAP would be equally susceptible to toxicity. Hepatocytes and renal epithelial cells were prepared by collagenase digestion of tissues obtained from female Sprague-Dawley rats. Toxicity was monitored using trypan blue exclusion, oxygen consumption and ATP content. We measured the rate of PAP clearance and formation of PAP-glutathione conjugate by HPLC. We found that renal epithelial cells accumulated trypan blue and showed declines in oxygen consumption and ATP content at significantly lower concentrations of PAP and at earlier time points than hepatocytes. The half-life of PAP in hepatocyte incubations was significantly shorter (0.71+/-0.07 h) than in renal epithelial cell incubations (1.33+/-0.23 h), suggesting that renal epithelial cells were exposed to PAP for longer time periods than hepatocytes. Renal epithelial cells formed significantly less glutathione conjugates of PAP (PAP-SG) than did hepatocytes, consistent with less efficient detoxification of reactive PAP intermediates by renal epithelial cells. Finally, hepatocytes contained significant more reduced glutathione (NPSH) than did renal epithelial cells, possibly explaining the enhanced formation of PAP-SG by this cell population. In conclusion, our data indicates that renal epithelial cells are intrinsically more susceptible to PAP cytotoxicity than are hepatocytes. This enhanced cytotoxicity may be due to longer exposure to PAP and/or reduced detoxification of reactive intermediates due to lower concentrations

EGF stimulates Mg{sup 2+} influx in mammary epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trapani, Valentina; Arduini, Daniela; Luongo, Francesca

2014-11-28

Highlights: • EGF stimulation potentiates Mg{sup 2+} influx into epithelial cells. • EGF-induced Mg{sup 2+} influx does not depend on the concomitantly induced Ca{sup 2+} signal. • EGF-induced Ca{sup 2+} signal is dependent on the presence of extracellular Mg{sup 2+}. • New players in EGF-mediated signaling might be exploited as therapeutic targets. - Abstract: Magnesium is well established as a fundamental factor that regulates cell proliferation. However, the molecular mechanisms linking mitogenic signals, extracellular magnesium availability and intracellular effectors are still largely unknown. In the present study we sought to determine whether EGF regulates magnesium homeostasis in normal HC11 mammarymore » epithelial cells. To this end, we measured Mg{sup 2+} and Ca{sup 2+} fluxes by confocal imaging in live cells loaded with specific fluorescent ion indicators (Mag-Fluo-4 and Fluo-4, respectively). EGF stimulation induces a rapid and sustained increase in intracellular Mg{sup 2+}, concomitantly with a rise in intracellular calcium. The increase in intracellular Mg{sup 2+} derives from an influx from the extracellular compartment, and does not depend on Ca{sup 2+}. On the contrary, the increase in intracellular Ca{sup 2+} derives from intracellular stores, and is impaired in the absence of extracellular magnesium. Inhibition of the EGF receptor tyrosine kinase by Tyrphostin AG1478 markedly inhibits EGF-induced Mg{sup 2+} and Ca{sup 2+} signals. These findings demonstrate that not only does Mg{sup 2+} influx represent an important step in the physiological response of epithelial cells to EGF, but unexpectedly the EGF-induced Mg{sup 2+} influx is essential for the Ca{sup 2+} signal to occur.« less

Paracrine influence of human perivascular cells on the proliferation of adenocarcinoma alveolar epithelial cells.

PubMed

Kim, Eunbi; Na, Sunghun; An, Borim; Yang, Se-Ran; Kim, Woo Jin; Ha, Kwon-Soo; Han, Eun-Taek; Park, Won Sun; Lee, Chang-Min; Lee, Ji Yoon; Lee, Seung-Joon; Hong, Seok-Ho

2017-03-01

Understanding the crosstalk mechanisms between perivascular cells (PVCs) and cancer cells might be beneficial in preventing cancer development and metastasis. In this study, we investigated the paracrine influence of PVCs derived from human umbilical cords on the proliferation of lung adenocarcinoma epithelial cells (A549) and erythroleukemia cells (TF-1α and K562) in vitro using Transwell® co-culture systems. PVCs promoted the proliferation of A549 cells without inducing morphological changes, but had no effect on the proliferation of TF-1α and K562 cells. To identify the factors secreted from PVCs, conditioned media harvested from PVC cultures were analyzed by antibody arrays. We identified a set of cytokines, including persephin (PSPN), a neurotrophic factor, and a key regulator of oral squamous cell carcinoma progression. Supplementation with PSPN significantly increased the proliferation of A549 cells. These results suggested that PVCs produced a differential effect on the proliferation of cancer cells in a cell-type dependent manner. Further, secretome analyses of PVCs and the elucidation of the molecular mechanisms could facilitate the discovery of therapeutic target(s) for lung cancer.

Isolation, separation, and characterization of epithelial and connective cells from rat palate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terranova, Victor Paul

1979-01-01

Epithelial and connective tissue cells were isolated from rat palate by sequential collagenase, hyaluronidase and trypsin digestion of the extracellular matrix. Differences between the two populations were noted with respect to total cell protein, total cell water, proline uptake and incorporation, percent collagen synthesized, effects of parathyroid hormone, metabolism of D-valine and cell density. Basal epithelial cells were subsequently separated from the heterogeneous epithelial cell population on shallow linear density gradients by velocity centrifugation. The type of collagen synthesized by the basal epithelial cells was compared to the type of collagen synthesized by the connective tissue cells by means ofmore » labeled amino acid incorporation ratios. Cells isolated from the epithelial and connective tissue were compared. From these studies it can be concluded that epithelial and connective tissue cells can be isolated from rat palate as viable and distinct populations with respect to the biochemical parameters examined. Furthermore, subpopulations can be separated and biochemically characterized.« less

Epithelial rotation is preceded by planar symmetry breaking of actomyosin and protects epithelial tissue from cell deformations.

PubMed

Viktorinová, Ivana; Henry, Ian; Tomancak, Pavel

2017-11-01

Symmetry breaking is involved in many developmental processes that form bodies and organs. One of them is the epithelial rotation of developing tubular and acinar organs. However, how epithelial cells move, how they break symmetry to define their common direction, and what function rotational epithelial motions have remains elusive. Here, we identify a dynamic actomyosin network that breaks symmetry at the basal surface of the Drosophila follicle epithelium of acinar-like primitive organs, called egg chambers, and may represent a candidate force-generation mechanism that underlies the unidirectional motion of this epithelial tissue. We provide evidence that the atypical cadherin Fat2, a key planar cell polarity regulator in Drosophila oogenesis, directs and orchestrates transmission of the intracellular actomyosin asymmetry cue onto a tissue plane in order to break planar actomyosin symmetry, facilitate epithelial rotation in the opposite direction, and direct the elongation of follicle cells. In contrast, loss of this rotational motion results in anisotropic non-muscle Myosin II pulses that are disorganized in plane and causes cell deformations in the epithelial tissue of Drosophila eggs. Our work demonstrates that atypical cadherins play an important role in the control of symmetry breaking of cellular mechanics in order to facilitate tissue motion and model epithelial tissue. We propose that their functions may be evolutionarily conserved in tubular/acinar vertebrate organs.

Epithelial rotation is preceded by planar symmetry breaking of actomyosin and protects epithelial tissue from cell deformations

PubMed Central

Henry, Ian; Tomancak, Pavel

2017-01-01

Symmetry breaking is involved in many developmental processes that form bodies and organs. One of them is the epithelial rotation of developing tubular and acinar organs. However, how epithelial cells move, how they break symmetry to define their common direction, and what function rotational epithelial motions have remains elusive. Here, we identify a dynamic actomyosin network that breaks symmetry at the basal surface of the Drosophila follicle epithelium of acinar-like primitive organs, called egg chambers, and may represent a candidate force-generation mechanism that underlies the unidirectional motion of this epithelial tissue. We provide evidence that the atypical cadherin Fat2, a key planar cell polarity regulator in Drosophila oogenesis, directs and orchestrates transmission of the intracellular actomyosin asymmetry cue onto a tissue plane in order to break planar actomyosin symmetry, facilitate epithelial rotation in the opposite direction, and direct the elongation of follicle cells. In contrast, loss of this rotational motion results in anisotropic non-muscle Myosin II pulses that are disorganized in plane and causes cell deformations in the epithelial tissue of Drosophila eggs. Our work demonstrates that atypical cadherins play an important role in the control of symmetry breaking of cellular mechanics in order to facilitate tissue motion and model epithelial tissue. We propose that their functions may be evolutionarily conserved in tubular/acinar vertebrate organs. PMID:29176774

Probiotics promote endocytic allergen degradation in gut epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Chun-Hua; Liu, Zhi-Qiang; Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON

Highlights: Black-Right-Pointing-Pointer Knockdown of A20 compromised the epithelial barrier function. Black-Right-Pointing-Pointer The fusion of endosome/lysosome was disturbed in the A20-deficient HT-29 cells. Black-Right-Pointing-Pointer Antigens transported across A20-deficient HT-29 monolayers conserved antigenicity. Black-Right-Pointing-Pointer Probiotic proteins increased the expression of A20 in HT-29 cells. -- Abstract: Background and aims: Epithelial barrier dysfunction plays a critical role in the pathogenesis of allergic diseases; the mechanism is to be further understood. The ubiquitin E3 ligase A20 (A20) plays a role in the endocytic protein degradation in the cells. This study aims to elucidate the role of A20 in the maintenance of gut epithelial barriermore » function. Methods: Gut epithelial cell line, HT-29 cell, was cultured into monolayers to evaluate the barrier function in transwells. RNA interference was employed to knock down the A20 gene in HT-29 cells to test the role of A20 in the maintenance of epithelial barrier function. Probiotic derived proteins were extracted from the culture supernatants using to enhance the expression of A20 in HT-29 cells. Results: The results showed that the knockdown of A20 compromised the epithelial barrier function in HT-29 monolayers, mainly increased the intracellular permeability. The fusion of endosome/lysosome was disturbed in the A20-deficient HT-29 cells. Allergens collected from the transwell basal chambers of A20-deficient HT-29 monolayers still conserved functional antigenicity. Treating with probiotic derived proteins increased the expression of A20 in HT-29 cells and promote the barrier function. Conclusion: A20 plays an important role in the maintenance of epithelial barrier function as shown by HT-29 monolayer. Probiotic derived protein increases the expression of A20 and promote the HT-29 monolayer barrier function.« less

Adhesion to the host cell surface is sufficient to mediate Listeria monocytogenes entry into epithelial cells

PubMed Central

Ortega, Fabian E.; Rengarajan, Michelle; Chavez, Natalie; Radhakrishnan, Prathima; Gloerich, Martijn; Bianchini, Julie; Siemers, Kathleen; Luckett, William S.; Lauer, Peter; Nelson, W. James; Theriot, Julie A.

2017-01-01

The intestinal epithelium is the first physiological barrier breached by the Gram-positive facultative pathogen Listeria monocytogenes during an in vivo infection. Listeria monocytogenes binds to the epithelial host cell receptor E-cadherin, which mediates a physical link between the bacterium and filamentous actin (F-actin). However, the importance of anchoring the bacterium to F-actin through E-cadherin for bacterial invasion has not been tested directly in epithelial cells. Here we demonstrate that depleting αE-catenin, which indirectly links E-cadherin to F-actin, did not decrease L. monocytogenes invasion of epithelial cells in tissue culture. Instead, invasion increased due to increased bacterial adhesion to epithelial monolayers with compromised cell–cell junctions. Furthermore, expression of a mutant E-cadherin lacking the intracellular domain was sufficient for efficient L. monocytogenes invasion of epithelial cells. Importantly, direct biotin-mediated binding of bacteria to surface lipids in the plasma membrane of host epithelial cells was sufficient for uptake. Our results indicate that the only requirement for L. monocytogenes invasion of epithelial cells is adhesion to the host cell surface, and that E-cadherin–mediated coupling of the bacterium to F-actin is not required. PMID:28877987

Cigarette Smoke Suppresses Bik To Cause Epithelial Cell Hyperplasia and Mucous Cell Metaplasia

PubMed Central

Mebratu, Yohannes A.; Schwalm, Kurt; Smith, Kevin R.; Schuyler, Mark; Tesfaigzi, Yohannes

2011-01-01

Rationale: Aberrant regulation of airway epithelial cell numbers in airways leads to increased mucous secretions in chronic lung diseases such as chronic bronchitis. Because the Bcl-2 family of proteins is crucial for airway epithelial homeostasis, identifying the players that reduce cigarette smoke (CS)-induced mucous cell metaplasia can help to develop effective therapies. Objectives: To identify the Bcl-2 family of proteins that play a role in reducing CS-induced mucous cell metaplasia. Methods: We screened for dysregulated expression of the Bcl-2 family members. Measurements and Main Results: We identified Bik to be significantly reduced in bronchial brushings of patients with chronic epithelial cell hyperplasia compared with nondiseased control subjects. Reduced Bik but increased MUC5AC mRNA levels were also detected when normal human airway epithelial cells (HAECs) were exposed to CS or when autopsy tissues from former smokers with and without chronic bronchitis were compared. Similarly, exposure of C57Bl/6 mice to CS resulted in increased numbers of epithelial and mucous cells per millimeter of basal lamina, along with reduced Bik but increased Muc5ac expression, and this change was sustained even when mice were allowed to recover in filtered air for 8 weeks. Restoring Bik expression significantly suppressed CS-induced mucous cell metaplasia in differentiated primary HAEC cultures and in airways of mice in vivo. Bik blocked nuclear translocation of phospho-ERK1/2 to induce apoptosis of HAECs. The conserved Leu61 within Bik and ERK1/2 activation were essential to induce cell death in hyperplastic mucous cells. Conclusions: These studies show that CS suppresses Bik expression to block airway epithelia cell death and thereby increases epithelial cell hyperplasia in chronic bronchitis. PMID:21317312

Candida albicans triggers interleukin-8 secretion by oral epithelial cells.

PubMed

Dongari-Bagtzoglou, A; Kashleva, H

2003-04-01

Oropharyngeal candidiasis is a frequent opportunistic infection associated with immunocompromised hosts. Candida albicans is the principal species responsible for this infection. Production of interleukin-8 (IL-8), by oral epithelial cells can be expected to play a major role in the recruitment and activation of professional phagocytes at the infected site. The purpose of this study was to determine whether C. albicans triggers secretion of IL-8 by oral epithelial cells in vitro and investigate mechanisms of host cell-fungal interactions that trigger such responses. Oral epithelial cell lines (SCC4, SCC15, and OKF6/TERT-2) as well as primary gingival epithelial cells were used. Epithelial cells were cocultured with C. albicans, strains SC5314, ATCC28366 or ATCC32077, for 24-48 hr, and supernatants were analyzed for IL-8 content by ELISA. A germination-deficient mutant (efg1/efg1 cph1/cph1), otherwise isogenic to strain SC5314, was used to assess the requirement for germination in triggering IL-8 responses. In order to ascertain whether direct contact of yeast with host cells is required to trigger cytokine production, epithelial cells were separated from yeast using cell culture inserts. To test whether IL-8 secretion is dependent on IL-1alpha activity, epithelial cells were challenged with viable C. albicans in the presence or absence of neutralizing anti-IL-1alpha antibody or IL-1ra, and IL-8 secretion was measured in the supernatants. All cell lines and primary cultures responded to C. albicans with an increase in IL-8 secretion. IL-8 responses were contact-dependent, strain-specific, required yeast viability and germination into hyphae, and were in part autoregulated by IL-1alpha. Copyright 2003 Elsevier Science Ltd.

Neonatal diethylstilbestrol exposure alters the metabolic profile of uterine epithelial cells

PubMed Central

Yin, Yan; Lin, Congxing; Veith, G. Michael; Chen, Hong; Dhandha, Maulik; Ma, Liang

2012-01-01

SUMMARY Developmental exposure to diethylstilbestrol (DES) causes reproductive tract malformations, affects fertility and increases the risk of clear cell carcinoma of the vagina and cervix in humans. Previous studies on a well-established mouse DES model demonstrated that it recapitulates many features of the human syndrome, yet the underlying molecular mechanism is far from clear. Using the neonatal DES mouse model, the present study uses global transcript profiling to systematically explore early gene expression changes in individual epithelial and mesenchymal compartments of the neonatal uterus. Over 900 genes show differential expression upon DES treatment in either one or both tissue layers. Interestingly, multiple components of peroxisome proliferator-activated receptor-γ (PPARγ)-mediated adipogenesis and lipid metabolism, including PPARγ itself, are targets of DES in the neonatal uterus. Transmission electron microscopy and Oil-Red O staining further demonstrate a dramatic increase in lipid deposition in uterine epithelial cells upon DES exposure. Neonatal DES exposure also perturbs glucose homeostasis in the uterine epithelium. Some of these neonatal DES-induced metabolic changes appear to last into adulthood, suggesting a permanent effect of DES on energy metabolism in uterine epithelial cells. This study extends the list of biological processes that can be regulated by estrogen or DES, and provides a novel perspective for endocrine disruptor-induced reproductive abnormalities. PMID:22679223

Let-7a modulates particulate matter (≤ 2.5 μm)-induced oxidative stress and injury in human airway epithelial cells by targeting arginase 2.

PubMed

Song, Lei; Li, Dan; Gu, Yue; Li, Xiaoping; Peng, Liping

2016-10-01

Epidemiological studies show that particulate matter (PM) with an aerodynamic diameter ≤ 2.5 μm (PM2.5) is associated with cardiorespiratory diseases via the induction of excessive oxidative stress. However, the precise mechanism underlying PM2.5-mediated oxidative stress injury has not been fully elucidated. Accumulating evidence has indicated the microRNA let-7 family might play a role in PM-mediated pathological processes. In this study, we investigated the role of let-7a in oxidative stress and cell injury in human bronchial epithelial BEAS2B (B2B) cells after PM2.5 exposure. The let-7a level was the most significantly decreased in B2B cells after PM2.5 exposure. The overexpression of let-7a suppressed intracellular reactive oxygen species levels and the percentage of apoptotic cells after PM2.5 exposure, while the let-7a level decreased arginase 2 (ARG2) mRNA and protein levels in B2B cells by directly targeting the ARG2 3'-untranslated region. ARG2 expression was upregulated in B2B cells during PM2.5 treatment, and ARG2 knockdown could remarkably reduce oxidative stress and cellular injury. Moreover, its restoration could abrogate the protective effects of let-7a against PM2.5-induced injury. In conclusion, let-7a decreases and ARG2 increases resulting from PM2.5 exposure may exacerbate oxidative stress, cell injury and apoptosis of B2B cells. The let-7a/ARG2 axis is a likely therapeutic target for PM2.5-induced airway epithelial injury. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Human airway epithelial cells investigated by atomic force microscopy: A hint to cystic fibrosis epithelial pathology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lasalvia, Maria; Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari; Castellani, Stefano

The pathophysiology of cystic fibrosis (CF) airway disease stems from mutations in the CF Transmembrane Conductance Regulator (CFTR) gene, leading to a chronic respiratory disease. Actin cytoskeleton is disorganized in CF airway epithelial cells, likely contributing to the CF-associated basic defects, i.e. defective chloride secretion and sodium/fluid hypersorption. In this work, we aimed to find whether this alteration could be pointed out by means of Atomic Force Microscopy (AFM) investigation, as roughness and Young's elastic module. Moreover, we also sought to determine whether disorganization of actin cytoskeleton is linked to hypersoption of apical fluid. Not only CFBE41o- (CFBE) cells, immortalizedmore » airway epithelial cells homozygous for the F508del CFTR allele, showed a different morphology in comparison with 16HBE14o- (16HBE) epithelial cells, wild-type for CFTR, but also they displayed a lack of stress fibers, suggestive of a disorganized actin cytoskeleton. AFM measurements showed that CFBE cells presented a higher membrane roughness and decreased rigidity as compared with 16HBE cells. CFBE overexpressing wtCFTR became more elongated than the parental CFBE cell line and presented actin stress fibers. CFBE cells absorbed more fluid from the apical compartment. Study of fluid absorption with the F-actin-depolymerizing agent Latrunculin B demonstrated that actin cytoskeletal disorganization increased fluid absorption, an effect observed at higher magnitude in 16HBE than in CFBE cells. For the first time, we demonstrate that actin cytoskeleton disorganization is reflected by AFM parameters in CF airway epithelial cells. Our data also strongly suggest that the lack of stress fibers is involved in at least one of the early step in CF pathophysiology at the levels of the airways, i.e. fluid hypersorption. - Highlights: • CF bronchial epithelial (CFBE) cells show a disorganized actin cytoskeleton. • CFBE cells present high roughness and low rigidity

Endothelial induced EMT in breast epithelial cells with stem cell properties.

PubMed

Sigurdsson, Valgardur; Hilmarsdottir, Bylgja; Sigmundsdottir, Hekla; Fridriksdottir, Agla J R; Ringnér, Markus; Villadsen, Rene; Borg, Ake; Agnarsson, Bjarni A; Petersen, Ole William; Magnusson, Magnus K; Gudjonsson, Thorarinn

2011-01-01

Epithelial to mesenchymal transition (EMT) is a critical event in cancer progression and is closely linked to the breast epithelial cancer stem cell phenotype. Given the close interaction between the vascular endothelium and cancer cells, especially at the invasive front, we asked whether endothelial cells might play a role in EMT. Using a 3D culture model we demonstrate that endothelial cells are potent inducers of EMT in D492 an immortalized breast epithelial cell line with stem cell properties. Endothelial induced mesenchymal-like cells (D492M) derived from D492, show reduced expression of keratins, a switch from E-Cadherin (E-Cad) to N-Cadherin (N-Cad) and enhanced migration. Acquisition of cancer stem cell associated characteristics like increased CD44(high)/CD24(low) ratio, resistance to apoptosis and anchorage independent growth was also seen in D492M cells. Endothelial induced EMT in D492 was partially blocked by inhibition of HGF signaling. Basal-like breast cancer, a vascular rich cancer with stem cell properties and adverse prognosis has been linked with EMT. We immunostained several basal-like breast cancer samples for endothelial and EMT markers. Cancer cells close to the vascular rich areas show no or decreased expression of E-Cad and increased N-Cad expression suggesting EMT. Collectively, we have shown in a 3D culture model that endothelial cells are potent inducers of EMT in breast epithelial cells with stem cell properties. Furthermore, we demonstrate that basal-like breast cancer contains cells with an EMT phenotype, most prominently close to vascular rich areas of these tumors. We conclude that endothelial cells are potent inducers of EMT and may play a role in progression of basal-like breast cancer.

Endothelial Induced EMT in Breast Epithelial Cells with Stem Cell Properties

PubMed Central

Sigurdsson, Valgardur; Hilmarsdottir, Bylgja; Sigmundsdottir, Hekla; Fridriksdottir, Agla J. R.; Ringnér, Markus; Villadsen, Rene; Borg, Ake; Agnarsson, Bjarni A.; Petersen, Ole William; Magnusson, Magnus K.; Gudjonsson, Thorarinn

2011-01-01

Epithelial to mesenchymal transition (EMT) is a critical event in cancer progression and is closely linked to the breast epithelial cancer stem cell phenotype. Given the close interaction between the vascular endothelium and cancer cells, especially at the invasive front, we asked whether endothelial cells might play a role in EMT. Using a 3D culture model we demonstrate that endothelial cells are potent inducers of EMT in D492 an immortalized breast epithelial cell line with stem cell properties. Endothelial induced mesenchymal-like cells (D492M) derived from D492, show reduced expression of keratins, a switch from E-Cadherin (E-Cad) to N-Cadherin (N-Cad) and enhanced migration. Acquisition of cancer stem cell associated characteristics like increased CD44high/CD24low ratio, resistance to apoptosis and anchorage independent growth was also seen in D492M cells. Endothelial induced EMT in D492 was partially blocked by inhibition of HGF signaling. Basal-like breast cancer, a vascular rich cancer with stem cell properties and adverse prognosis has been linked with EMT. We immunostained several basal-like breast cancer samples for endothelial and EMT markers. Cancer cells close to the vascular rich areas show no or decreased expression of E-Cad and increased N-Cad expression suggesting EMT. Collectively, we have shown in a 3D culture model that endothelial cells are potent inducers of EMT in breast epithelial cells with stem cell properties. Furthermore, we demonstrate that basal-like breast cancer contains cells with an EMT phenotype, most prominently close to vascular rich areas of these tumors. We conclude that endothelial cells are potent inducers of EMT and may play a role in progression of basal-like breast cancer. PMID:21915264

Intestinal Epithelial Cells Modulate Antigen-Presenting Cell Responses to Bacterial DNA

PubMed Central

Campeau, J. L.; Salim, S. Y.; Albert, E. J.; Hotte, N.

2012-01-01

Intestinal epithelial cells and antigen-presenting cells orchestrate mucosal innate immunity. This study investigated the role of bacterial DNA in modulating epithelial and bone marrow-derived antigen-presenting cells (BM-APCs) and subsequent T-lymphocyte responses. Murine MODE-K epithelial cells and BM-APCs were treated with DNA from either Bifidobacterium breve or Salmonella enterica serovar Dublin directly and under coculture conditions with CD4+ T cells. Apical stimulation of MODE-K cells with S. Dublin DNA enhanced secretion of cytokines from underlying BM-APCs and induced interleukin-17 (IL-17) and gamma interferon (IFN-γ) secretion from CD4+ T cells. Bacterial DNA isolated from either strain induced maturation and increased cytokine secretion from BM-APCs. Conditioned medium from S. Dublin-treated MODE-K cells elicited an increase in cytokine secretion similar to that seen for S. Dublin DNA. Treatment of conditioned medium from MODE-K cells with RNase and protease prevented the S. Dublin-induced increased cytokine secretion. Oral feeding of mice with B. breve DNA resulted in enhanced levels of colonic IL-10 and transforming growth factor β (TGFβ) compared with what was seen for mice treated with S. Dublin DNA. In contrast, feeding mice with S. Dublin DNA increased levels of colonic IL-17 and IL-12p70. T cells from S. Dublin DNA-treated mice secreted high levels of IL-12 and IFN-γ compared to controls and B. breve DNA-treated mice. These results demonstrate that intestinal epithelial cells are able to modulate subsequent antigen-presenting and T-cell responses to bacterial DNA with pathogenic but not commensal bacterial DNA inducing effector CD4+ T lymphocytes. PMID:22615241

Evidence for circulating cancer stem-like cells and epithelial-mesenchymal transition phenotype in the pleurospheres derived from lung adenocarcinoma using liquid biopsy.

PubMed

Mirza, Sheefa; Jain, Nayan; Rawal, Rakesh

2017-03-01

Lung cancer stem cells are supposed to be the main drivers of tumor initiation, maintenance, drug resistance, and relapse of the disease. Hence, identification of the cellular and molecular aspects of these cells is a prerequisite for targeted therapy of lung cancer. Currently, analysis of circulating tumor cells has the potential to become the main diagnostic technique to monitor disease progression or therapeutic response as it is non-invasive. However, accurate detection of circulating tumor cells has remained a challenge, as epithelial cell markers used so far are not always trustworthy for detecting circulating tumor cells, especially during epithelial-mesenchymal transition. As cancer stem cells are the only culprit to initiate metastatic tumors, our aim was to isolate and characterize circulating tumor stem cells rather than circulating tumor cells from the peripheral blood of NSCLC adenocarcinoma as limited data are available addressing the gene expression profiling of lung cancer stem cells. Here, we reveal that CD44(+)/CD24(-) population in circulation not only exhibit stem cell-related genes but also possess epithelial-mesenchymal transition characteristics. In conclusion, the use of one or more cancer stem cell markers along with epithelial, mesenchymal and epithelial mesenchymal transition markers will prospectively provide the most precise assessment of the threat for recurrence and metastatic disease and has a great potential for forthcoming applications in harvesting circulating tumor stem cells and their downstream applications. Our results will aid in developing diagnostic and prognostic modalities and personalized treatment regimens like dendritic cell-based immunotherapy that can be utilized for targeting and eliminating circulating tumor stem cells, to significantly reduce the possibility of relapse and improve clinical outcomes.

Interactions of Aspergillus fumigatus Conidia with Airway Epithelial Cells: A Critical Review

PubMed Central

Croft, Carys A.; Culibrk, Luka; Moore, Margo M.; Tebbutt, Scott J.

2016-01-01

Aspergillus fumigatus is an environmental filamentous fungus that also acts as an opportunistic pathogen able to cause a variety of symptoms, from an allergic response to a life-threatening disseminated fungal infection. The infectious agents are inhaled conidia whose first point of contact is most likely to be an airway epithelial cell (AEC). The interaction between epithelial cells and conidia is multifaceted and complex, and has implications for later steps in pathogenesis. Increasing evidence has demonstrated a key role for the airway epithelium in the response to respiratory pathogens, particularly at early stages of infection; therefore, elucidating the early stages of interaction of conidia with AECs is essential to understand the establishment of infection in cohorts of at-risk patients. Here, we present a comprehensive review of the early interactions between A. fumigatus and AECs, including bronchial and alveolar epithelial cells. We describe mechanisms of adhesion, internalization of conidia by AECs, the immune response of AECs, as well as the role of fungal virulence factors, and patterns of fungal gene expression characteristic of early infection. A clear understanding of the mechanisms involved in the early establishment of infection by A. fumigatus could point to novel targets for therapy and prophylaxis. PMID:27092126

TNFα-induced IKKβ complex activation influences epithelial, but not stromal cell survival in endometriosis.

PubMed

Kocbek, Vida; Grandi, Giovanni; Blank, Fabian; Wotzkow, Carlos; Bersinger, Nick A; Mueller, Michael D; Kyo, Satoru; McKinnon, Brett D

2016-11-01

immortalized cell lines and not primary cell cultures and only low sample numbers were available for the study. The regulation of aberrant signalling pathways represents a promising yet relatively unexplored area of endometriosis progression. The IKKβ complex is activated by inflammation and is critical nodal point of numerous downstream kinase-signalling pathways, including NFκB (nuclear factor κB), mTOR (mammalian target of rapamycin) and BAD (Bcl2-antagonist of cell death). This study shows a significant relationship between peritoneal fluid TNFα and IKKβ activation in epithelial cells that will have significant consequences for the continued survival of these cells at ectopic locations through the regulation of downstream pathways. None. The study was funded by the Swiss National Science Foundation (Grant Number 320030_140774). The authors have no conflict of interest to declare. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Coreceptors and Their Ligands in Epithelial γδ T Cell Biology

PubMed Central

Witherden, Deborah A.; Johnson, Margarete D.; Havran, Wendy L.

2018-01-01

Epithelial tissues line the body providing a protective barrier from the external environment. Maintenance of these epithelial barrier tissues critically relies on the presence of a functional resident T cell population. In some tissues, the resident T cell population is exclusively comprised of γδ T cells, while in others γδ T cells are found together with αβ T cells and other lymphocyte populations. Epithelial-resident γδ T cells function not only in the maintenance of the epithelium, but are also central to the repair process following damage from environmental and pathogenic insults. Key to their function is the crosstalk between γδ T cells and neighboring epithelial cells. This crosstalk relies on multiple receptor–ligand interactions through both the T cell receptor and accessory molecules leading to temporal and spatial regulation of cytokine, chemokine, growth factor, and extracellular matrix protein production. As antigens that activate epithelial γδ T cells are largely unknown and many classical costimulatory molecules and coreceptors are not used by these cells, efforts have focused on identification of novel coreceptors and ligands that mediate pivotal interactions between γδ T cells and their neighbors. In this review, we discuss recent advances in the understanding of functions for these coreceptors and their ligands in epithelial maintenance and repair processes. PMID:29686687

Tenofovir Inhibits Wound Healing of Epithelial Cells and Fibroblasts from the Upper and Lower Human Female Reproductive Tract

PubMed Central

Rodriguez-Garcia, Marta; Patel, Mickey V.; Shen, Zheng; Bodwell, Jack; Rossoll, Richard M.; Wira, Charles R.

2017-01-01

Disruption of the epithelium in the female reproductive tract (FRT) is hypothesized to increase HIV infection risk by interfering with barrier protection and facilitating HIV-target cell recruitment. Here we determined whether Tenofovir (TFV), used vaginally in HIV prevention trials, and Tenofovir alafenamide (TAF), an improved prodrug of TFV, interfere with wound healing in the human FRT. TFV treatment of primary epithelial cells and fibroblasts from the endometrium (EM), endocervix (CX) and ectocervix (ECX) significantly delayed wound closure. Reestablishment of tight junctions was compromised in EM and CX epithelial cells even after wound closure occurred. In contrast, TAF had no inhibitory effect on wound closure or tight junction formation following injury. TAF accumulated inside genital epithelial cells as TFV-DP, the active drug form. At elevated levels of TAF treatment to match TFV intracellular TFV-DP concentrations, both equally impaired barrier function, while wound closure was more sensitive to TFV. Furthermore, TFV but not TAF increased elafin and MIP3a secretion following injury, molecules known to be chemotactic for HIV-target cells. Our results highlight the need of evaluating antiretroviral effects on genital wound healing in future clinical trials. A possible link between delayed wound healing and increased risk of HIV acquisition deserves further investigation. PMID:28368028

Characterization of primary cultures of adult human epididymis epithelial cells.

PubMed

Leir, Shih-Hsing; Browne, James A; Eggener, Scott E; Harris, Ann

2015-03-01

To establish cultures of epithelial cells from all regions of the human epididymis to provide reagents for molecular approaches to functional studies of this epithelium. Experimental laboratory study. University research institute. Epididymis from seven patients undergoing orchiectomy for suspected testicular cancer without epididymal involvement. Human epididymis epithelial cells harvested from adult epididymis tissue. Establishment of a robust culture protocol for adult human epididymal epithelial cells. Cultures of caput, corpus, and cauda epithelial cells were established from epididymis tissue of seven donors. Cells were passaged up to eight times and maintained differentiation markers. They were also cryopreserved and recovered successfully. Androgen receptor, clusterin, and cysteine-rich secretory protein 1 were expressed in cultured cells, as shown by means of immunofluorescence, Western blot, and quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The distribution of other epididymis markers was also shown by means of qRT-PCR. Cultures developed transepithelial resistance (TER), which was androgen responsive in the caput but androgen insensitive in the corpus and cauda, where unstimulated TER values were much higher. The results demonstrate a robust in vitro culture system for differentiated epithelial cell types in the caput, corpus, and cauda of the human epididymis. These cells will be a valuable resource for molecular analysis of epididymis epithelial function, which has a pivotal role in male fertility. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Galectin-3 modulates the polarized surface delivery of β1-integrin in epithelial cells.

PubMed

Hönig, Ellena; Ringer, Karina; Dewes, Jenny; von Mach, Tobias; Kamm, Natalia; Kreitzer, Geri; Jacob, Ralf

2018-05-10

Epithelial cells require a precise intracellular transport and sorting machinery in order to establish and maintain their polarized architecture. This machinery includes beta-galactoside binding galectins for glycoprotein targeting to the apical membrane. Galectin-3 sorts cargo destined for the apical plasma membrane into vesicular carriers. After delivery of cargo to the apical milieu, galectin-3 recycles back into sorting organelles. We analyzed the role of galectin-3 in the polarized distribution of β1-integrin in MDCK cells. Integrins are located primarily at the basolateral domain of epithelial cells. We demonstrate that a minor pool of β1-integrin interacts with galectin-3 at the apical plasma membrane. Knockdown of galectin-3 decreases apical delivery of β1-integrin. This loss is restored by supplementation with recombinant galectin-3 and galectin-3 overexpression. Our data suggest that galectin-3 targets newly synthesized β1-integrin to the apical membrane and promotes apical delivery of β1-integrin internalized from the basolateral membrane. In parallel, galectin-3 knockout results in a reduction in cell proliferation and an impairment in proper cyst development. Our results suggest that galectin-3 modulates the surface distribution of β1-integrin and affects the morphogenesis of polarized cells. © 2018. Published by The Company of Biologists Ltd.

Role of alveolar epithelial early growth response-1 (Egr-1) in CD8+ T cell-mediated lung injury.

PubMed

Ramana, Chilakamarti V; Cheng, Guang-Shing; Kumar, Aseem; Kwon, Hyung-Joo; Enelow, Richard I

2009-12-01

Influenza infection of the distal airways results in severe lung injury, a considerable portion of which is immunopathologic and attributable to the host responses. We have used a mouse model to specifically investigate the role of antiviral CD8(+) T cells in this injury, and have found that the critical effector molecule is TNF-alpha expressed by the T cells upon antigen recognition. Interestingly, the immunopathology which ensues is characterized by significant accumulation of host inflammatory cells, recruited by chemokines expressed by the target alveolar epithelial cells. In this study we analyzed the mechanisms involved in the induction of epithelial chemokine expression triggered by antigen-specific CD8(+) T cell recognition, and demonstrate that the early growth response-1 (Egr-1) transcription factor is rapidly induced in epithelial cells, both in vitro and ex vivo, and that this is a critical regulator of a host of inflammatory chemokines. Genetic deficiency of Egr-1 significantly abrogates both the chemokine expression and the immunopathologic injury associated with T cell recognition, and it directly regulates transcriptional activity of a model CXC chemokine, MIP-2. We further demonstrate that Egr-1 induction is triggered by TNF-alpha-dependent ERK activation, and inhibition of this pathway ablates Egr-1 expression. These findings suggest that Egr-1 may represent an important target in mitigating the immunopathology of severe influenza infection.

Role of alveolar epithelial Early growth response-1 (Egr-1) in CD8+ T Cell mediated Lung Injury

PubMed Central

Ramana, Chilakamarti V.; Cheng, Guang-Shing; Kumar, Aseem; Kwon, Hyung- Joo; Enelow, Richard I.

2009-01-01

Influenza infection of the distal airways results in severe lung injury, a considerable portion of which is immunopathologic and attributable to the host responses. We have used a mouse model to specifically investigate the role of antiviral CD8+ T cells in this injury, and have found that the critical effector molecule is TNF-α expressed by the T cells upon antigen recognition. Interestingly, the immunopathology which ensues is characterized by significant accumulation of host inflammatory cells, recruited by chemokines expressed by the target alveolar epithelial cells. In this study we analyzed the mechanisms involved in the induction of epithelial chemokine expression triggered by antigen-specific CD8+ T cell recognition, and demonstrate that the Early growth response-1 (Egr-1) transcription factor is rapidly induced in epithelial cells, both in vitro and ex vivo, and that this is a critical regulator of a host of inflammatory chemokines. Genetic deficiency of Egr-1 significantly abrogates both the chemokine expression and the immunopathologic injury associated with T cell recognition, and it directly regulates transcriptional activity of a model CXC chemokine, MIP-2. We further demonstrate that Egr-1 induction is triggered by TNF-α– dependent ERK activation, and inhibition of this pathway ablates Egr-1 expression. These findings suggest that Egr-1 may represent an important target in mitigating the immunopathology of severe influenza infection. PMID:19786304

Stromal–epithelial cell interactions and alteration of branching morphogenesis in macromastic mammary glands

PubMed Central

Zhong, Aimei; Wang, Guohua; Yang, Jie; Xu, Qijun; Yuan, Quan; Yang, Yanqing; Xia, Yun; Guo, Ke; Horch, Raymund E; Sun, Jiaming

2014-01-01

True macromastia is a rare but disabling condition characterized by massive breast growth. The aetiology and pathogenic mechanisms for this disorder remain largely unexplored because of the lack of in vivo or in vitro models. Previous studies suggested that regulation of epithelial cell growth and development by oestrogen was dependent on paracrine growth factors from the stroma. In this study, a co-culture model containing epithelial and stromal cells was used to investigate the interactions of these cells in macromastia. Epithelial cell proliferation and branching morphogenesis were measured to assess the effect of macromastic stromal cells on epithelial cells. We analysed the cytokines secreted by stromal cells and identified molecules that were critical for effects on epithelial cells. Our results indicated a significant increase in cell proliferation and branching morphogenesis of macromastic and non-macromastic epithelial cells when co-cultured with macromastic stromal cells or in conditioned medium from macromastic stromal cells. Hepatocyte growth factor (HGF) is a key factor in epithelial–stromal interactions of macromastia-derived cell cultures. Blockade of HGF with neutralizing antibodies dramatically attenuated epithelial cell proliferation in conditioned medium from macromastic stromal cells. The epithelial–stromal cell co-culture model demonstrated reliability for studying interactions of mammary stromal and epithelial cells in macromastia. In this model, HGF secreted by macromastic stromal cells was found to play an important role in modifying the behaviour of co-cultured epithelial cells. This model allows further studies to investigate basic cellular and molecular mechanisms in tissue from patients with true breast hypertrophy. PMID:24720804

Keratin 8 and 18 Loss in Epithelial Cancer Cells Increases Collective Cell Migration and Cisplatin Sensitivity through Claudin1 Up-regulation*

PubMed Central

Fortier, Anne-Marie; Asselin, Eric; Cadrin, Monique

2013-01-01

Keratins 8 and 18 (K8/18) are simple epithelial cell-specific intermediate filament proteins. Keratins are essential for tissue integrity and are involved in intracellular signaling pathways that regulate cell response to injuries, cell growth, and death. K8/18 expression is maintained during tumorigenesis; hence, they are used as a diagnostic marker in tumor pathology. In recent years, studies have provided evidence that keratins should be considered not only as markers but also as regulators of cancer cell signaling. The loss of K8/18 expression during epithelial-mesenchymal transition (EMT) is associated with metastasis and chemoresistance. In the present study, we investigated whether K8/18 expression plays an active role in EMT. We show that K8/18 stable knockdown using shRNA increased collective migration and invasiveness of epithelial cancer cells without modulating EMT markers. K8/18-depleted cells showed PI3K/Akt/NF-κB hyperactivation and increased MMP2 and MMP9 expression. K8/18 deletion also increased cisplatin-induced apoptosis. Increased Fas receptor membrane targeting suggests that apoptosis is enhanced via the extrinsic pathway. Interestingly, we identified the tight junction protein claudin1 as a regulator of these processes. This is the first indication that modulation of K8/18 expression can influence the phenotype of epithelial cancer cells at a transcriptional level and supports the hypothesis that keratins play an active role in cancer progression. PMID:23449973

Injurious effects of wool and grain dusts on alveolar epithelial cells and macrophages in vitro.

PubMed Central

Brown, D M; Donaldson, K

1991-01-01

Epidemiological studies of workers in wool textile mills have shown a direct relation between the concentration of wool dust in the air and respiratory symptoms. Injurious effects of wool dust on the bronchial epithelium could be important in causing inflammation and irritation. A pulmonary epithelial cell line in vitro was therefore used to study the toxic effects of wool dust. Cells of the A549 epithelial cell line were labelled with 51Cr and treated with whole wool dusts and extracts of wool, after which injury was assessed. Also, the effects of grain dust, which also causes a form of airway obstruction, were studied. The epithelial injury was assessed by measuring 51Cr release from cells as an indication of lysis, and by monitoring cells which had detached from the substratum. No significant injury to A549 cells was caused by culture with any of the dusts collected from the air but surface "ledge" dust caused significant lysis at some doses. Quartz, used as a toxic control dust, caused significant lysis at the highest concentration of 100 micrograms/well. To determine whether any injurious material was soluble the dusts were incubated in saline and extracts collected. No extracts caused significant injury to epithelial cells. A similar lack of toxicity was found when 51Cr labelled control alveolar macrophages were targets for injury. Significant release of radiolabel was evident when macrophages were exposed to quartz at concentrations of 10 and 20 micrograms/well, there being no significant injury with either wool or grain dusts. These data suggest that neither wool nor grain dust produce direct injury to epithelial cells, and further studies are necessary to explain inflammation leading to respiratory symptoms in wool and grain workers. PMID:2015211

Uranium induces oxidative stress in lung epithelial cells

PubMed Central

Periyakaruppan, Adaikkappan; Kumar, Felix; Sarkar, Shubhashish; Sharma, Chidananda S.

2009-01-01

Uranium compounds are widely used in the nuclear fuel cycle, antitank weapons, tank armor, and also as a pigment to color ceramics and glass. Effective management of waste uranium compounds is necessary to prevent exposure to avoid adverse health effects on the population. Health risks associated with uranium exposure includes kidney disease and respiratory disorders. In addition, several published results have shown uranium or depleted uranium causes DNA damage, mutagenicity, cancer and neurological defects. In the current study, uranium toxicity was evaluated in rat lung epithelial cells. The study shows uranium induces significant oxidative stress in rat lung epithelial cells followed by concomitant decrease in the antioxidant potential of the cells. Treatment with uranium to rat lung epithelial cells also decreased cell proliferation after 72 h in culture. The decrease in cell proliferation was attributed to loss of total glutathione and superoxide dismutase in the presence of uranium. Thus the results indicate the ineffectiveness of antioxidant system’s response to the oxidative stress induced by uranium in the cells. PMID:17124605

Glycolipid-Dependent, Protease Sensitive Internalization of Pseudomonas aeruginosa Into Cultured Human Respiratory Epithelial Cells

PubMed Central

Emam, Aufaugh; Carter, William G; Lingwood, Clifford

2010-01-01

Internalization of PAK strain Pseudomonas aeruginosa into human respiratory epithelial cell lines and HeLa cervical cancer cells in vitro was readily demonstrable via a gentamycin protection assay. Depletion of target cell glycosphingolipids (GSLs) using a glucosyl ceramide synthase inhibitor, P4, completely prevented P. aeruginosa internalization. In contrast, P4 treatment had no effect on the internalization of Salmonella typhimurium into HeLa cells. Internalized P. aeruginosa were within membrane vacuoles, often containing microvesicles, between the bacterium and the limiting membrane. P. aeruginosa internalization was markedly enhanced by target cell pretreatment with the exogenous GSL, deacetyl gangliotetraosyl ceramide (Gg4). Gg4 binds the lipid raft marker, GM1 ganglioside. Target cell pretreatment with TLCK, but not other (serine) protease inhibitors, prevented both P. aeruginosa host cell binding and internalization. NFkB inhibition also prevented internalization. A GSL-containing lipid-raft model of P. aeruginosa host cell binding/internalization is proposed PMID:21270937

MiR-424-5p reversed epithelial-mesenchymal transition of anchorage-independent HCC cells by directly targeting ICAT and suppressed HCC progression

PubMed Central

Zhang, Ying; Li, Tao; Guo, Pengbo; Kang, Jia; Wei, Qing; Jia, Xiaoqing; Zhao, Wei; Huai, Wanwan; Qiu, Yumin; Sun, Lei; Han, Lihui

2014-01-01

Resistance to anoikis and Epithelial-mesenchymal transition (EMT) are two processes critically involved in cancer metastasis. In this study, we demonstrated that after anchorage deprival, hepatocellular carcinoma (HCC) cells not only resisted anoikis, but also exhibited EMT process. Microarray expression profiling revealed that expression of miR-424-5p was significantly decreased in anoikis-resistant HCC cells. Ectopic overexpression of miR-424-5p was sufficient to reverse resistance to anoikis, block EMT process and inhibit malignant behaviors of HCC cells. Target analysis showed that a potent β-catenin inhibitor, ICAT/CTNNBIP1 was a direct target of miR-424-5p. Further study demonstrated that miR-424-5p reversed resistance to anoikis and EMT of HCCs by directly targeting ICAT and further maintaining the E-cadherin/β-catanin complex on the cellular membrance. In vivo study further demonstrated that miR-424-5p significantly inhibited the tumorigenicity of HCC cells in nude mice. Clinical investigation demonstrated that miR-424-5p was significantly downregulated in HCC tissues compared with that of the non-cancerous liver tissues, and this decreased expression of miR-424-5p was significantly correlated with higher pathological grades and more advanced TNM stages. Therefore, aberrant expression of miR-424-5p is critically involved in resistance to anoikis and EMT during the metastatic process of HCC, and its downregulation significantly contributes to liver cancer progression. PMID:25175916

Emergence of an apical epithelial cell surface in vivo

PubMed Central

Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté; Wallingford, John B.

2016-01-01

Epithelial sheets are crucial components of all metazoan animals, enclosing organs and protecting the animal from its environment. Epithelial homeostasis poses unique challenges, as addition of new cells and loss of old cells must be achieved without disrupting the fluid-tight barrier and apicobasal polarity of the epithelium. Several studies have identified cell biological mechanisms underlying extrusion of cells from epithelia, but far less is known of the converse mechanism by which new cells are added. Here, we combine molecular, pharmacological and laser-dissection experiments with theoretical modelling to characterize forces driving emergence of an apical surface as single nascent cells are added to a vertebrate epithelium in vivo. We find that this process involves the interplay between cell-autonomous actin-generated pushing forces in the emerging cell and mechanical properties of neighboring cells. Our findings define the forces driving this cell behavior, contributing to a more comprehensive understanding of epithelial homeostasis. PMID:26766441

CD24 can be used to isolate Lgr5+ putative colonic epithelial stem cells in mice

PubMed Central

King, Jeffrey B.; von Furstenberg, Richard J.; Smith, Brian J.; McNaughton, Kirk K.; Galanko, Joseph A.

2012-01-01

A growing body of evidence has implicated CD24, a cell-surface protein, as a marker of colorectal cancer stem cells and target for antitumor therapy, although its presence in normal colonic epithelium has not been fully characterized. Previously, our group showed that CD24-based cell sorting can be used to isolate a fraction of murine small intestinal epithelial cells enriched in actively cycling stem cells. Similarly, we hypothesized that CD24-based isolation of colonic epithelial cells would generate a fraction enriched in actively cycling colonic epithelial stem cells (CESCs). Immunohistochemistry performed on mouse colonic tissue showed CD24 expression in the bottom half of proximal colon crypts and the crypt base in the distal colon. This pattern of distribution was similar to enhanced green fluorescent protein (EGFP) expression in Lgr5-EGFP mice. Areas expressing CD24 contained actively proliferating cells as determined by ethynyl deoxyuridine (EdU) incorporation, with a distinct difference between the proximal colon, where EdU-labeled cells were most frequent in the midcrypt, and the distal colon, where they were primarily at the crypt base. Flow cytometric analyses of single epithelial cells, identified by epithelial cell adhesion molecule (EpCAM) positivity, from mouse colon revealed an actively cycling CD24+ fraction that contained the majority of Lgr5-EGFP+ putative CESCs. Transcript analysis by quantitative RT-PCR confirmed enrichment of active CESC markers [leucine-rich-repeat-containing G protein-coupled receptor 5 (Lgr5), ephrin type B receptor 2 (EphB2), and CD166] in the CD24+EpCAM+ fraction but also showed enrichment of quiescent CESC markers [leucine-rich repeats and immunoglobin domains (Lrig), doublecortin and calmodulin kinase-like 1 (DCAMKL-1), and murine telomerase reverse transcriptase (mTert)]. We conclude that CD24-based sorting in wild-type mice isolates a colonic epithelial fraction highly enriched in actively cycling and quiescent

Effects of Weaning on Intestinal Upper Villus Epithelial Cells of Piglets

PubMed Central

Wang, Xiaocheng; Tan, Bie; Li, Tiejun; Yin, Yulong

2016-01-01

The intestinal upper villus epithelial cells represent the differentiated epithelial cells and play key role in digesting and absorbing lumenal nutrients. Weaning stress commonly results in a decrease in villus height and intestinal dysfunction in piglets. However, no study have been conducted to test the effects of weaning on the physiology and functions of upper villus epithelial cells. A total of 40 piglets from 8 litters were weaned at 14 days of age and one piglet from each litter was killed at 0 d (w0d), 1 d (w1d), 3 d (w3d), 5 d (w5d), and 7 d (w7d) after weaning, respectively. The upper villus epithelial cells in mid-jejunum were isolated using the distended intestinal sac method. The expression of proteins in upper villus epithelial cells was analyzed using the isobaric tags for relative and absolute quantification or Western blotting. The expression of proteins involved in energy metabolism, Golgi vesicle transport, protein amino acid glycosylation, secretion by cell, transmembrane transport, ion transport, nucleotide catabolic process, translational initiation, and epithelial cell differentiation and apoptosis, was mainly reduced during the post-weaning period, and these processes may be regulated by mTOR signaling pathway. These results indicated that weaning inhibited various cellular processes in jejunal upper villus epithelial cells, and provided potential new directions for exploring the effects of weaning on the functions of intestine and improving intestinal functions in weaning piglets. PMID:27022727

Contraction and elongation: Mechanics underlying cell boundary deformations in epithelial tissue.

PubMed

Hara, Yusuke

2017-06-01

The cell-cell boundaries of epithelial cells form cellular frameworks at the apical side of tissues. Deformations in these boundaries, for example, boundary contraction and elongation, and the associated forces form the mechanical basis of epithelial tissue morphogenesis. In this review, using data from recent Drosophila studies on cell boundary contraction and elongation, I provide an overview of the mechanism underlying the bi-directional deformations in the epithelial cell boundary, that are sustained by biased accumulations of junctional and apico-medial non-muscle myosin II. Moreover, how the junctional tensions exist on cell boundaries in different boundary dynamics and morphologies are discussed. Finally, some future perspectives on how recent knowledge about single cell boundary-level mechanics will contribute to our understanding of epithelial tissue morphogenesis are discussed. © 2017 Japanese Society of Developmental Biologists.

Quantification of epithelial cells in coculture with fibroblasts by fluorescence image analysis.

PubMed

Krtolica, Ana; Ortiz de Solorzano, Carlos; Lockett, Stephen; Campisi, Judith

2002-10-01

To demonstrate that senescent fibroblasts stimulate the proliferation and neoplastic transformation of premalignant epithelial cells (Krtolica et al.: Proc Natl Acad Sci USA 98:12072-12077, 2001), we developed methods to quantify the proliferation of epithelial cells cocultured with fibroblasts. We stained epithelial-fibroblast cocultures with the fluorescent DNA-intercalating dye 4,6-diamidino-2-phenylindole (DAPI), or expressed green fluorescent protein (GFP) in the epithelial cells, and then cultured them with fibroblasts. The cocultures were photographed under an inverted microscope with appropriate filters, and the fluorescent images were captured with a digital camera. We modified an image analysis program to selectively recognize the smaller, more intensely fluorescent epithelial cell nuclei in DAPI-stained cultures and used the program to quantify areas with DAPI fluorescence generated by epithelial nuclei or GFP fluorescence generated by epithelial cells in each field. Analysis of the image areas with DAPI and GFP fluorescences produced nearly identical quantification of epithelial cells in coculture with fibroblasts. We confirmed these results by manual counting. In addition, GFP labeling permitted kinetic studies of the same coculture over multiple time points. The image analysis-based quantification method we describe here is an easy and reliable way to monitor cells in coculture and should be useful for a variety of cell biological studies. Copyright 2002 Wiley-Liss, Inc.

Substrate stiffness affects epithelial-mesenchymal transition of cervical cancer cells through miR-106b and its target protein DAB2.

PubMed

Piao, Jinlan; You, Ke; Guo, Yanli; Zhang, Youyi; Li, Zijian; Geng, Li

2017-06-01

The effects of different substrate stiffness were investigated on epithelial-mesenchymal transition (EMT) of cervical cancer cell lines and the role of miR-106b and its target protein DAB2 therein. Cervical cancer cell lines HeLa and SiHa were cultured on artificial substrates with different stiffness prepared using different ratios of acrylamide and bis-acrylamide. Changes of microRNA profiles were detected using microRNA chip analysis, and the expression levels of EMT-related markers E-cadherin and vimentin were detected using western blotting and real-time PCR. In addition, the effects of miR-106b overexpression as well as miR-106b and DAB2 knockdown on expression of E-cadherin and vimentin were also examined using western blotting and real-time PCR. The results showed that i) cervical cancer cell lines SiHa and HeLa cultured on substrate with stiffness of 20 kPa had the strongest EMT ability, showed the highest levels of vimentin and lowest levels of E-cadherin, compared with cells cultured on substrate with stiffness of 1 kPa; ii) miR-106b knockdown reversed the effects of substrate stiffness on EMT of cervical cancer cells, while miR-106 overexpression and DAB2 knockdown induced EMT of cervical cancer cells cultured on substrate with stiffness of 20 kPa. Overall, the results indicated that substrate stiffness could regulate EMT of cervical cancer cell lines HeLa and SiHa at least partially through miR-106b and its downstream target DAB2.

DA-6034 Induces [Ca(2+)]i Increase in Epithelial Cells.

PubMed

Yang, Yu-Mi; Park, Soonhong; Ji, Hyewon; Kim, Tae-Im; Kim, Eung Kweon; Kang, Kyung Koo; Shin, Dong Min

2014-04-01

DA-6034, a eupatilin derivative of flavonoid, has shown potent effects on the protection of gastric mucosa and induced the increases in fluid and glycoprotein secretion in human and rat corneal and conjunctival cells, suggesting that it might be considered as a drug for the treatment of dry eye. However, whether DA-6034 induces Ca(2+) signaling and its underlying mechanism in epithelial cells are not known. In the present study, we investigated the mechanism for actions of DA-6034 in Ca(2+) signaling pathways of the epithelial cells (conjunctival and corneal cells) from human donor eyes and mouse salivary gland epithelial cells. DA-6034 activated Ca(2+)-activated Cl(-) channels (CaCCs) and increased intracellular calcium concentrations ([Ca(2+)]i) in primary cultured human conjunctival cells. DA-6034 also increased [Ca(2+)]i in mouse salivary gland cells and human corneal epithelial cells. [Ca(2+)]i increase of DA-6034 was dependent on the Ca(2+) entry from extracellular and Ca(2+) release from internal Ca(2+) stores. Interestingly, these effects of DA-6034 were related to ryanodine receptors (RyRs) but not phospholipase C/inositol 1,4,5-triphosphate (IP3) pathway and lysosomal Ca(2+) stores. These results suggest that DA-6034 induces Ca(2+) signaling via extracellular Ca(2+) entry and RyRs-sensitive Ca(2+) release from internal Ca(2+) stores in epithelial cells.

Leptin expression in human mammary epithelial cells and breast milk.

PubMed

Smith-Kirwin, S M; O'Connor, D M; De Johnston, J; Lancey, E D; Hassink, S G; Funanage, V L

1998-05-01

Leptin has recently been shown to be produced by the human placenta and potentially plays a role in fetal and neonatal growth. Many functions of the placenta are replaced by the mammary gland in terms of providing critical growth factors for the newborn. In this study, we show that leptin is produced by human mammary epithelial cells as revealed by RT/PCR analysis of total RNA from mammary gland and immunohistochemical staining of breast tissue, cultured mammary epithelial cells, and secretory epithelial cells present in human milk. We also verify that immunoreactive leptin is present in whole milk at 30- to 150-fold higher concentrations than skim milk. We propose that leptin is secreted by mammary epithelial cells in milk fat globules, which partition into the lipid portion of breast milk.

Pleiotrophin regulates lung epithelial cell proliferation and differentiation during fetal lung development via beta-catenin and Dlk1.

PubMed

Weng, Tingting; Gao, Li; Bhaskaran, Manoj; Guo, Yujie; Gou, Deming; Narayanaperumal, Jeyaparthasarathy; Chintagari, Narendranath Reddy; Zhang, Kexiong; Liu, Lin

2009-10-09

The role of pleiotrophin in fetal lung development was investigated. We found that pleiotrophin and its receptor, protein-tyrosine phosphatase receptor beta/zeta, were highly expressed in mesenchymal and epithelial cells of the fetal lungs, respectively. Using isolated fetal alveolar epithelial type II cells, we demonstrated that pleiotrophin promoted fetal type II cell proliferation and arrested type II cell trans-differentiation into alveolar epithelial type I cells. Pleiotrophin also increased wound healing of injured type II cell monolayer. Knockdown of pleiotrophin influenced lung branching morphogenesis in a fetal lung organ culture model. Pleiotrophin increased the tyrosine phosphorylation of beta-catenin, promoted beta-catenin translocation into the nucleus, and activated T cell factor/lymphoid enhancer factor transcription factors. Dlk1, a membrane ligand that initiates the Notch signaling pathway, was identified as a downstream target of the pleiotrophin/beta-catenin pathway by endogenous dlk1 expression, promoter assay, and chromatin immunoprecipitation. These results provide evidence that pleiotrophin regulates fetal type II cell proliferation and differentiation via integration of multiple signaling pathways including pleiotrophin, beta-catenin, and Notch pathways.

Lateral adhesion drives reintegration of misplaced cells into epithelial monolayers

PubMed Central

St Johnston, Daniel

2016-01-01

Cells in simple epithelia orient their mitotic spindles in the plane of the epithelium so that both daughter cells are born within the epithelial sheet. This is assumed to be important to maintain epithelial integrity and prevent hyperplasia, because misaligned divisions give rise to cells outside the epithelium1,2. Here we test this assumption in three types of Drosophila epithelia; the cuboidal follicle epithelium, the columnar early embryonic ectoderm, and the pseudostratified neuroepithelium. Ectopic expression of Inscuteable in these tissues reorients mitotic spindles, resulting in one daughter cell being born outside of the epithelial layer. Live imaging reveals that these misplaced cells reintegrate into the tissue. Reducing the levels of the lateral homophilic adhesion molecules Neuroglian or Fasciclin 2 disrupts reintegration, giving rise to extra-epithelial cells, whereas disruption of adherens junctions has no effect. Thus, the reinsertion of misplaced cells appears to be driven by lateral adhesion, which pulls cells born outside the epithelia layer back into it. Our findings reveal a robust mechanism that protects epithelia against the consequences of misoriented divisions. PMID:26414404

Adherence of Lactobacillus crispatus to vaginal epithelial cells from women with or without a history of recurrent urinary tract infection.

PubMed

Kwok, Louisa; Stapleton, Ann E; Stamm, Walter E; Hillier, Sharon L; Wobbe, Cheryl L; Gupta, Kalpana

2006-11-01

Lactobacillus crispatus strain CTV-05 is a vaginal probiotic proposed for use in women with recurrent urinary tract infection to reduce vaginal colonization with Escherichia coli and the risk of urinary tract infection. However, the ability of this probiotic strain to adhere to the target mucosa, vaginal epithelial cells, has not been assessed in women with recurrent urinary tract infection. We measured the adherence of L. crispatus strain CTV-05 to vaginal epithelial cells collected from more than 100 premenopausal women with (cases) and without (controls) a history of recurrent urinary tract infection. We also examined the effects of relevant host factors on bacterial adherence. Bacterial adherence assays were performed by combining L. crispatus CTV-05 with exfoliated vaginal epithelial cells collected from 51 case women and 51 controls. L. crispatus CTV-05 adhered in high numbers to vaginal epithelial cells from women with recurrent urinary tract infection (mean adherence of 50.5 lactobacilli per vaginal epithelial cell) and controls (mean adherence of 39.4 lactobacilli per vaginal epithelial cell). Adherence was significantly higher using vaginal epithelial cells from women with a maternal history of urinary tract infection (p = 0.036) and a nonsecretor phenotype (p < 0.001), but was not significantly affected by recent spermicide use, oral contraceptive use, menstrual cycle phase or sexual activity. L. crispatus strain CTV-05 is highly adherent to vaginal epithelial cells collected from a large sample of premenopausal women with or without a history of recent recurrent urinary tract infection. These data strongly support further evaluation of this probiotic in clinical trials of women with recurrent urinary tract infection.

Pancreatic stellate cells promote epithelial-mesenchymal transition in pancreatic cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kikuta, Kazuhiro; Masamune, Atsushi, E-mail: amasamune@med.tohoku.ac.jp; Watanabe, Takashi

2010-12-17

Research highlights: {yields} Recent studies have shown that pancreatic stellate cells (PSCs) promote the progression of pancreatic cancer. {yields} Pancreatic cancer cells co-cultured with PSCs showed loose cell contacts and scattered, fibroblast-like appearance. {yields} PSCs decreased the expression of epithelial markers but increased that of mesenchymal markers, along with increased migration. {yields} This study suggests epithelial-mesenchymal transition as a novel mechanism by which PSCs contribute to the aggressive behavior of pancreatic cancer cells. -- Abstract: The interaction between pancreatic cancer cells and pancreatic stellate cells (PSCs), a major profibrogenic cell type in the pancreas, is receiving increasing attention. There ismore » accumulating evidence that PSCs promote the progression of pancreatic cancer by increasing cancer cell proliferation and invasion as well as by protecting them from radiation- and gemcitabine-induced apoptosis. Because epithelial-mesenchymal transition (EMT) plays a critical role in the progression of pancreatic cancer, we hypothesized that PSCs promote EMT in pancreatic cancer cells. Panc-1 and SUIT-2 pancreatic cancer cells were indirectly co-cultured with human PSCs isolated from patients undergoing operation for pancreatic cancer. The expression of epithelial and mesenchymal markers was examined by real-time PCR and immunofluorescent staining. The migration of pancreatic cancer cells was examined by scratch and two-chamber assays. Pancreatic cancer cells co-cultured with PSCs showed loose cell contacts and a scattered, fibroblast-like appearance. The expression of E-cadherin, cytokeratin 19, and membrane-associated {beta}-catenin was decreased, whereas vimentin and Snail (Snai-1) expression was increased more in cancer cells co-cultured with PSCs than in mono-cultured cells. The migration of pancreatic cancer cells was increased by co-culture with PSCs. The PSC-induced decrease of E-cadherin expression was not

Uterine epithelial cell proliferation and endometrial hyperplasia: evidence from a mouse model

PubMed Central

Gao, Yang; Li, Shu; Li, Qinglei

2014-01-01

In the uterus, epithelial cell proliferation changes during the estrous cycle and pregnancy. Uncontrolled epithelial cell proliferation results in implantation failure and/or cancer development. Transforming growth factor-β (TGF-β) signaling is a fundamental regulator of diverse biological processes and is indispensable for multiple reproductive functions. However, the in vivo role of TGF-β signaling in uterine epithelial cells remains poorly defined. We have shown that in the uterus, conditional deletion of the Type 1 receptor for TGF-β (Tgfbr1) using anti-Müllerian hormone receptor type 2 (Amhr2) Cre leads to myometrial defects. Here, we describe enhanced epithelial cell proliferation by immunostaining of Ki67 in the uteri of these mice. The aberration culminated in endometrial hyperplasia in aged females. To exclude the potential influence of ovarian steroid hormones, the proliferative status of uterine epithelial cells was assessed following ovariectomy. Increased uterine epithelial cell proliferation was also revealed in ovariectomized Tgfbr1 Amhr2-Cre conditional knockout mice. We further demonstrated that transcript levels for fibroblast growth factor 10 (Fgf10) were markedly up-regulated in Tgfbr1 Amhr2-Cre conditional knockout uteri. Consistently, treatment of primary uterine stromal cells with TGF-β1 significantly reduced Fgf10 mRNA expression. Thus, our findings suggest a potential involvement of TGFBR1-mediated signaling in the regulation of uterine epithelial cell proliferation, and provide genetic evidence supporting the role of uterine epithelial cell proliferation in the pathogenesis of endometrial hyperplasia. PMID:24770950

Impaired airway epithelial cell responses from children with asthma to rhinoviral infection.

PubMed

Kicic, A; Stevens, P T; Sutanto, E N; Kicic-Starcevich, E; Ling, K-M; Looi, K; Martinovich, K M; Garratt, L W; Iosifidis, T; Shaw, N C; Buckley, A G; Rigby, P J; Lannigan, F J; Knight, D A; Stick, S M

2016-11-01

The airway epithelium forms an effective immune and physical barrier that is essential for protecting the lung from potentially harmful inhaled stimuli including viruses. Human rhinovirus (HRV) infection is a known trigger of asthma exacerbations, although the mechanism by which this occurs is not fully understood. To explore the relationship between apoptotic, innate immune and inflammatory responses to HRV infection in airway epithelial cells (AECs) obtained from children with asthma and non-asthmatic controls. In addition, to test the hypothesis that aberrant repair of epithelium from asthmatics is further dysregulated by HRV infection. Airway epithelial brushings were obtained from 39 asthmatic and 36 non-asthmatic children. Primary cultures were established and exposed to HRV1b and HRV14. Virus receptor number, virus replication and progeny release were determined. Epithelial cell apoptosis, IFN-β production, inflammatory cytokine release and epithelial wound repair and proliferation were also measured. Virus proliferation and release was greater in airway epithelial cells from asthmatics but this was not related to the number of virus receptors. In epithelial cells from asthmatic children, virus infection dampened apoptosis, reduced IFN-β production and increased inflammatory cytokine production. HRV1b infection also inhibited wound repair capacity of epithelial cells isolated from non-asthmatic children and exaggerated the defective repair response seen in epithelial cells from asthmatics. Addition of IFN-β restored apoptosis, suppressed virus replication and improved repair of airway epithelial cells from asthmatics but did not reduce inflammatory cytokine production. Collectively, HRV infection delays repair and inhibits apoptotic processes in epithelial cells from non-asthmatic and asthmatic children. The delayed repair is further exaggerated in cells from asthmatic children and is only partially reversed by exogenous IFN-β. © 2016 John Wiley & Sons

Epithelial Cell Rests of Malassez Contain Unique Stem Cell Populations Capable of Undergoing Epithelial–Mesenchymal Transition

PubMed Central

Xiong, Jimin; Mrozik, Krzysztof; Gronthos, Stan

2012-01-01

The epithelial cell rests of Malassez (ERM) are odontogenic epithelial cells located within the periodontal ligament matrix. While their function is unknown, they may support tissue homeostasis and maintain periodontal ligament space or even contribute to periodontal regeneration. We investigated the notion that ERM contain a subpopulation of stem cells that could undergo epithelial–mesenchymal transition and differentiate into mesenchymal stem-like cells with multilineage potential. For this purpose, ERM collected from ovine incisors were subjected to different inductive conditions in vitro, previously developed for the characterization of bone marrow mesenchymal stromal/stem cells (BMSC). We found that ex vivo-expanded ERM expressed both epithelial (cytokeratin-8, E-cadherin, and epithelial membrane protein-1) and BMSC markers (CD44, CD29, and heat shock protein-90β). Integrin α6/CD49f could be used for the enrichment of clonogenic cell clusters [colony-forming units-epithelial cells (CFU-Epi)]. Integrin α6/CD49f-positive-selected epithelial cells demonstrated over 50- and 7-fold greater CFU-Epi than integrin α6/CD49f-negative cells and unfractionated cells, respectively. Importantly, ERM demonstrated stem cell-like properties in their differentiation capacity to form bone, fat, cartilage, and neural cells in vitro. When transplanted into immunocompromised mice, ERM generated bone, cementum-like and Sharpey's fiber-like structures. Additionally, gene expression studies showed that osteogenic induction of ERM triggered an epithelial–mesenchymal transition. In conclusion, ERM are unusual cells that display the morphological and phenotypic characteristics of ectoderm-derived epithelial cells; however, they also have the capacity to differentiate into a mesenchymal phenotype and thus represent a unique stem cell population within the periodontal ligament. PMID:22122577

Brca1 regulates in vitro differentiation of mammary epithelial cells.

PubMed

Kubista, Marion; Rosner, Margit; Kubista, Ernst; Bernaschek, Gerhard; Hengstschläger, Markus

2002-07-18

Murine Brca1 is widely expressed during development in different tissues. Why alterations of BRCA1 lead specifically to breast and ovarian cancer is currently not clarified. Here we show that Brca1 protein expression is upregulated during mammary epithelial differentiation of HC11 cells, during differentiation of C2C12 myoblasts into myotubes and during neuronal differentiation of N1E-115 cells. Ectopic overexpression of BRCA1 and downregulation of endogenous Brca1 expression specifically affect the regulation of mammary epithelial cell differentiation. Accelerated mammary epithelial cell differentiation upon high ectopic BRCA1 expression is not a consequence of the anti-proliferative capacity of this tumor suppressor and independent of functional p53. Overexpression of the BRCA1 variant lacking the large central exon 11 has no effects on mammary epithelial cell differentiation. These data provide new insights into the cellular role of Brca1.

Celiac Disease: Role of the Epithelial Barrier.

PubMed

Schumann, Michael; Siegmund, Britta; Schulzke, Jörg D; Fromm, Michael

2017-03-01

In celiac disease (CD) a T-cell-mediated response to gluten is mounted in genetically predisposed individuals, resulting in a malabsorptive enteropathy histologically highlighted by villous atrophy and crypt hyperplasia. Recent data point to the epithelial layer as an under-rated hot spot in celiac pathophysiology to date. This overview summarizes current functional and genetic evidence on the role of the epithelial barrier in CD, consisting of the cell membranes and the apical junctional complex comprising sealing as well as ion and water channel-forming tight junction proteins and the adherens junction. Moreover, the underlying mechanisms are discussed, including apoptosis of intestinal epithelial cells, biology of intestinal stem cells, alterations in the apical junctional complex, transcytotic uptake of gluten peptides, and possible implications of a defective epithelial polarity. Current research is directed toward new treatment options for CD that are alternatives or complementary therapeutics to a gluten-free diet. Thus, strategies to target an altered epithelial barrier therapeutically also are discussed.

Nicotine transport in lung and non-lung epithelial cells.

PubMed

Takano, Mikihisa; Kamei, Hidetaka; Nagahiro, Machi; Kawami, Masashi; Yumoto, Ryoko

2017-11-01

Nicotine is rapidly absorbed from the lung alveoli into systemic circulation during cigarette smoking. However, mechanism underlying nicotine transport in alveolar epithelial cells is not well understood to date. In the present study, we characterized nicotine uptake in lung epithelial cell lines A549 and NCI-H441 and in non-lung epithelial cell lines HepG2 and MCF-7. Characteristics of [ 3 H]nicotine uptake was studied using these cell lines. Nicotine uptake in A549 cells occurred in a time- and temperature-dependent manner and showed saturation kinetics, with a Km value of 0.31mM. Treatment with some organic cations such as diphenhydramine and pyrilamine inhibited nicotine uptake, whereas treatment with organic cations such as carnitine and tetraethylammonium did not affect nicotine uptake. Extracellular pH markedly affected nicotine uptake, with high nicotine uptake being observed at high pH up to 11.0. Modulation of intracellular pH with ammonium chloride also affected nicotine uptake. Treatment with valinomycin, a potassium ionophore, did not significantly affect nicotine uptake, indicating that nicotine uptake is an electroneutral process. For comparison, we assessed the characteristics of nicotine uptake in another lung epithelial cell line NCI-H441 and in non-lung epithelial cell lines HepG2 and MCF-7. Interestingly, these cell lines showed similar characteristics of nicotine uptake with respect to pH dependency and inhibition by various organic cations. The present findings suggest that a similar or the same pH-dependent transport system is involved in nicotine uptake in these cell lines. A novel molecular mechanism of nicotine transport is proposed. Copyright © 2017 Elsevier Inc. All rights reserved.

Understanding and Targeting Cell Growth Networks in Breast Cancer

DTIC Science & Technology

2010-04-01

both monitoring and preventing the outbreak of cancer cells. A common target of ARF is the NPM/B23 oncogene, an abundant protein of the nucleolus ...phenotype is dependent on NPM and p68DDX5 expression in the nucleolus , with loss of either capable of completely reversing the phenotype back to...ARF, DDX5, and NPM in the nucleolus of breast epithelial cells and how they impact both ribosome biogenesis and cell growth to prevent and/or promote

Rubus idaeus L. reverses epithelial-to-mesenchymal transition and suppresses cell invasion and protease activities by targeting ERK1/2 and FAK pathways in human lung cancer cells.

PubMed

Hsieh, Yih-Shou; Chu, Shu-Chen; Hsu, Li-Sung; Chen, Kuo-Shuen; Lai, Ming-Tsung; Yeh, Chia-Heng; Chen, Pei-Ni

2013-12-01

Epithelial to mesenchymal transition (EMT) has been considered essential for cancer metastasis, a multistep complicated process including local invasion, intravasation, extravasation, and proliferation at distant sites. Herein we provided molecular evidence associated with the antimetastatic effect of Rubus idaeus L. extracts (RIE) by showing a nearly complete inhibition on the invasion (p<0.001) of highly metastatic A549 cells via reduced activities of matrix metalloproteinase-2 (MMP-2) and urokinasetype plasminogen activator (u-PA). We performed Western blot to find that RIE could induce up-regulation of epithelial marker such as E-cadherin and α-catenin and inhibit the mesenchymal markers such as N-cadherin, fibronectin, snail-1, and vimentin. Selective snail-1 inhibition by snail-1-specific-siRNA also showed increased E-cadherin expression in A549 cells suggesting a possible involvement of snail-1 inhibition in RIE-caused increase in E-cadherin level. RIE also inhibited p-FAK, p-paxillin and AP-1 by Western blot analysis, indicating the anti-EMT effect of RIE in human lung carcinoma. Importantly, an in vivo BALB/c nude mice xenograft model showed that RIE treatment reduced tumor growth by oral gavage, and RIE represent promising candidates for future phytochemical-based mechanistic pathway-targeted cancer prevention strategies. Copyright © 2013 Elsevier Ltd. All rights reserved.

Melanin dependent survival of Apergillus fumigatus conidia in lung epithelial cells.

PubMed

Amin, Shayista; Thywissen, Andreas; Heinekamp, Thorsten; Saluz, Hans Peter; Brakhage, Axel A

2014-07-01

Aspergillus fumigatus is the most important air-borne pathogenic fungus of humans. Upon inhalation of conidia, the fungus makes close contact with lung epithelial cells, which only possess low phagocytic activity. These cells are in particular interesting to address the question whether there is some form of persistence of conidia of A. fumigatus in the human host. Therefore, by also using uracil-auxotrophic mutant strains, we were able to investigate the interaction of A549 lung epithelial cells and A. fumigatus conidia in detail for long periods. Interestingly, unlike professional phagocytes, our study showed that the presence of conidial dihydroxynaphthalene (DHN) melanin enhanced the uptake of A. fumigatus conidia by epithelial cells when compared with non-pigmented pksP mutant conidia. Furthermore, conidia of A. fumigatus were able to survive within epithelial cells. This was due to the presence of DHN melanin in the cell wall of conidia, because melanised wild-type conidia showed a higher survival rate inside epithelial cells and led to inhibition of acidification of phagolysosomes. Both effects were not observed for white (non-melanised) conidia of the pksP mutant strain. Moreover, in contrast to pksP mutant conidia, melanised wild-type conidia were able to inhibit the extrinsic apoptotic pathway in A549 lung epithelial cells even for longer periods. The anti-apoptotic effect was not restricted to conidia, because both conidia-derived melanin ghosts (cell-free DHN melanin) and a different type of melanin, dihydroxyphenylalanine (DOPA) melanin, acted anti-apoptotically. Taken together, these data indicate the possibility of melanin-dependent persistence of conidia in lung epithelial cells. Copyright © 2014 Elsevier GmbH. All rights reserved.

Interaction of the pathogenic mold Aspergillus fumigatus with lung epithelial cells

PubMed Central

Osherov, Nir

2012-01-01

Aspergillus fumigatus is an opportunistic environmental mold that can cause severe allergic responses in atopic individuals and poses a life-threatening risk for severely immunocompromised patients. Infection is caused by inhalation of fungal spores (conidia) into the lungs. The initial point of contact between the fungus and the host is a monolayer of lung epithelial cells. Understanding how these cells react to fungal contact is crucial to elucidating the pathobiology of Aspergillus-related disease states. The experimental systems, both in vitro and in vivo, used to study these interactions, are described. Distinction is made between bronchial and alveolar epithelial cells. The experimental findings suggest that lung epithelial cells are more than just “innocent bystanders” or a purely physical barrier against infection. They can be better described as an active extension of our innate immune system, operating as a surveillance mechanism that can specifically identify fungal spores and activate an offensive response to block infection. This response includes the internalization of adherent conidia and the release of cytokines, antimicrobial peptides, and reactive oxygen species. In the case of allergy, lung epithelial cells can dampen an over-reactive immune response by releasing anti-inflammatory compounds such as kinurenine. This review summarizes our current knowledge regarding the interaction of A. fumigatus with lung epithelial cells. A better understanding of the interactions between A. fumigatus and lung epithelial cells has therapeutic implications, as stimulation or inhibition of the epithelial response may alter disease outcome. PMID:23055997

αB-crystallin is essential for the TGF-β2-mediated epithelial to mesenchymal transition of lens epithelial cells.

PubMed

Nahomi, Rooban B; Pantcheva, Mina B; Nagaraj, Ram H

2016-05-15

Transforming growth factor (TGF)-β2-mediated pathways play a major role in the epithelial to mesenchymal transition (EMT) of lens epithelial cells (LECs) during secondary cataract formation, which is also known as posterior capsule opacification (PCO). Although αB-crystallin is a major protein in LEC, its role in the EMT remains unknown. In a human LEC line (FHL124), TGF-β2 treatment resulted in changes in the EMT-associated proteins at the mRNA and protein levels. This was associated with nuclear localization of αB-crystallin, phosphorylated Smad2 (pSmad2) (S245/250/255), pSmad3 (S423/425), Smad4 and Snail and the binding of αB-crystallin to these transcription factors, all of which were reduced by the down-regulation of αB-crystallin. Expression of the functionally defective R120G mutant of αB-crystallin reduced TGF-β2-induced EMT in LECs of αB-crystallin knockout (KO) mice. Treatment of bovine lens epithelial explants and mouse LEC with TGF-β2 resulted in changes in the EMT-associated proteins at the mRNA and protein levels. This was accompanied by increase in phosphorylation of p44/42 mitogen-activated protein kinases (MAPK) (T202/Y204), p38 MAPK (T180/Y182), protein kinase B (Akt) (S473) and Smad2 when compared with untreated cells. These changes were significantly reduced in αB-crystallin depleted or knocked out LEC. The removal of the fibre cell mass from the lens of wild-type (WT) mice resulted in the up-regulation of EMT-associated genes in the capsule-adherent epithelial cells, which was reduced in the αB-crystallin KO mice. Together, our data show that αB-crystallin plays a central role in the TGF-β2-induced EMT of LEC. αB-Crystallin could be targeted to prevent PCO and pathological fibrosis in other tissues. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

Establishment and Characterization of Immortalized Human Amniotic Epithelial Cells

PubMed Central

Zhou, Kaixuan; Koike, Chika; Yoshida, Toshiko; Okabe, Motonori; Fathy, Moustafa; Kyo, Satoru; Kiyono, Tohru; Saito, Shigeru

2013-01-01

Abstract Human amniotic epithelial cells (HAEs) have a low immunogenic profile and possess potent immunosuppressive properties. HAEs also have several characteristics similar to stem cells, and they are discarded after parturition. Thus, they could potentially be used in cell therapy with fewer ethical problems. HAEs have a short life, so our aim is to establish and characterize immortalized human amniotic epithelial cells (iHAEs). HAEs were introduced with viral oncogenes E6/E7 and with human telomerase reverse transcriptase (hTERT) to create iHAEs. These iHAEs have proliferated around 200 population doublings (PDs) for at least 12 months. High expression of stem cell markers (Oct 3/4, Nanog, Sox2, Klf4) and epithelial markers (CK5, CK18) were detected by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). These iHAEs were expanded in ultra-low-attachment dishes to form spheroids similarly to epithelial stem/precursor cells. High expression of mesenchymal (CD44, CD73, CD90, CD105) and somatic (CD24, CD29, CD271, Nestin) stem cell markers was detected by flow cytometry. The iHAEs showed adipogenic, osteogenic, neuronal, and cardiac differentiation abilities. In conclusion, the immortalization of HAEs with the characteristics of stem cells has been established, allowing these iHAEs to become useful for cell therapy and regenerative medicine. PMID:23298399

Endothelin-1 promotes epithelial-mesenchymal transition in human chondrosarcoma cells by repressing miR-300.

PubMed

Wu, Min-Huan; Huang, Pei-Han; Hsieh, Mingli; Tsai, Chun-Hao; Chen, Hsien-Te; Tang, Chih-Hsin

2016-10-25

Chondrosarcoma is a malignant tumor of mesenchymal origin predominantly composed of cartilage-producing cells. This type of bone cancer is extremely resistant to radiotherapy and chemotherapy. Surgical resection is the primary treatment, but is often difficult and not always practical for metastatic disease, so more effective treatments are needed. In particular, it would be helpful to identify molecular markers as targets for therapeutic intervention. Endothelin-1 (ET-1), a potent vasoconstrictor, has been shown to enhance chondrosarcoma angiogenesis and metastasis. We report that ET-1 promotes epithelial-mesenchymal transition (EMT) in human chondrosarcoma cells. EMT is a key pathological event in cancer progression, during which epithelial cells lose their junctions and apical-basal polarity and adopt an invasive phenotype. Our study verifies that ET-1 induces the EMT phenotype in chondrosarcoma cells via the AMP-activated protein kinase (AMPK) pathway. In addition, we show that ET-1 increases EMT by repressing miR-300, which plays an important role in EMT-enhanced tumor metastasis. We also show that miR-300 directly targets Twist, which in turn results in a negative regulation of EMT. We found a highly positive correlation between ET-1 and Twist expression levels as well as tumor stage in chondrosarcoma patient specimens. Therefore, ET-1 may represent a potential novel molecular therapeutic target in chondrosarcoma metastasis.

Cell competition with normal epithelial cells promotes apical extrusion of transformed cells through metabolic changes.

PubMed

Kon, Shunsuke; Ishibashi, Kojiro; Katoh, Hiroto; Kitamoto, Sho; Shirai, Takanobu; Tanaka, Shinya; Kajita, Mihoko; Ishikawa, Susumu; Yamauchi, Hajime; Yako, Yuta; Kamasaki, Tomoko; Matsumoto, Tomohiro; Watanabe, Hirotaka; Egami, Riku; Sasaki, Ayana; Nishikawa, Atsuko; Kameda, Ikumi; Maruyama, Takeshi; Narumi, Rika; Morita, Tomoko; Sasaki, Yoshiteru; Enoki, Ryosuke; Honma, Sato; Imamura, Hiromi; Oshima, Masanobu; Soga, Tomoyoshi; Miyazaki, Jun-Ichi; Duchen, Michael R; Nam, Jin-Min; Onodera, Yasuhito; Yoshioka, Shingo; Kikuta, Junichi; Ishii, Masaru; Imajo, Masamichi; Nishida, Eisuke; Fujioka, Yoichiro; Ohba, Yusuke; Sato, Toshiro; Fujita, Yasuyuki

2017-05-01

Recent studies have revealed that newly emerging transformed cells are often apically extruded from epithelial tissues. During this process, normal epithelial cells can recognize and actively eliminate transformed cells, a process called epithelial defence against cancer (EDAC). Here, we show that mitochondrial membrane potential is diminished in RasV12-transformed cells when they are surrounded by normal cells. In addition, glucose uptake is elevated, leading to higher lactate production. The mitochondrial dysfunction is driven by upregulation of pyruvate dehydrogenase kinase 4 (PDK4), which positively regulates elimination of RasV12-transformed cells. Furthermore, EDAC from the surrounding normal cells, involving filamin, drives the Warburg-effect-like metabolic alteration. Moreover, using a cell-competition mouse model, we demonstrate that PDK-mediated metabolic changes promote the elimination of RasV12-transformed cells from intestinal epithelia. These data indicate that non-cell-autonomous metabolic modulation is a crucial regulator for cell competition, shedding light on the unexplored events at the initial stage of carcinogenesis.

Characterization of kidney epithelial cells from the Florida manatee, Trichechus manatus latirostris.

PubMed

Sweat JMDunigan, D D; Wright, S D

2001-06-01

The West-Indian manatee, Trichechus manatus latirostris, is a herbivorous marine mammal found in the coastal waters of Florida. Because of their endangered status, animal experimentation is not allowed. Therefore, a cell line was developed and characterized from tissue collected during necropsies of the manatees. A primary cell culture was established by isolating single cells from kidney tissue using both enzymatic and mechanical techniques. Primary manatee kidney (MK) cells were subcultured for characterization. These cells were morphologically similar to the cell lines of epithelial origin. An immunocytochemistry assay was used to localize the cytokeratin filaments common to cells of epithelial origin. At second passage, epithelial-like cells had an average population-doubling time of 48 h, had an optimum seeding density of 5 x 10(3) cells/cm2, and readily attached to plastic culture plates with a high level of seeding efficiency. Although the epithelial-like cells had a rapid growth rate during the first three passages, the cloning potential was low. These cells did not form colonies in agar medium, were serum dependent, had a limited life span of approximately nine passages, and possessed cell-contact inhibition. These data suggest that the cells were finite (noncontinuous growth), did not possess transformed properties, and were of epithelial origin. These cells are now referred to as MK epithelial cells.

MTOR Suppresses Cigarette Smoke-Induced Epithelial Cell Death and Airway Inflammation in Chronic Obstructive Pulmonary Disease.

PubMed

Wang, Yong; Liu, Juan; Zhou, Jie-Sen; Huang, Hua-Qiong; Li, Zhou-Yang; Xu, Xu-Chen; Lai, Tian-Wen; Hu, Yue; Zhou, Hong-Bin; Chen, Hai-Pin; Ying, Song-Min; Li, Wen; Shen, Hua-Hao; Chen, Zhi-Hua

2018-04-15

Airway epithelial cell death and inflammation are pathological features of chronic obstructive pulmonary disease (COPD). Mechanistic target of rapamycin (MTOR) is involved in inflammation and multiple cellular processes, e.g., autophagy and apoptosis, but little is known about its function in COPD pathogenesis. In this article, we illustrate how MTOR regulates cigarette smoke (CS)-induced cell death, airway inflammation, and emphysema. Expression of MTOR was significantly decreased and its suppressive signaling protein, tuberous sclerosis 2 (TSC2), was increased in the airway epithelium of human COPD and in mouse lungs with chronic CS exposure. In human bronchial epithelial cells, CS extract (CSE) activated TSC2, inhibited MTOR, and induced autophagy. The TSC2-MTOR axis orchestrated CSE-induced autophagy, apoptosis, and necroptosis in human bronchial epithelial cells; all of which cooperatively regulated CSE-induced inflammatory cytokines IL-6 and IL-8 through the NF-κB pathway. Mice with a specific knockdown of Mtor in bronchial or alveolar epithelial cells exhibited significantly augmented airway inflammation and airspace enlargement in response to CS exposure, accompanied with enhanced levels of autophagy, apoptosis, and necroptosis in the lungs. Taken together, these data demonstrate that MTOR suppresses CS-induced inflammation and emphysema-likely through modulation of autophagy, apoptosis, and necroptosis-and thus suggest that activation of MTOR may represent a novel therapeutic strategy for COPD. Copyright © 2018 by The American Association of Immunologists, Inc.

GENE EXPRESSION PROFILING OF NORMAL HUMAN BRONCHIAL EPITHELIAL CELLS EXPOSED TO TRIVALENT ARSENICALS AND DIMETHYLTHIOARSINIC ACID

EPA Science Inventory

Lung is a major target for arsenic carcinogenesis in humans. However, the carcinogenic mode of action of arsenicals is unknown. We investigated, in human bronchial epithelial (BEAS2B) cells, the effects of inorganic arsenic (iAsIII), monomethylarsonous acid (MMAIII), dimethylarsi...

Studying Mucin Secretion from Human Bronchial Epithelial Cell Primary Cultures

PubMed Central

Abdullah, Lubna H.; Wolber, Cédric; Kesimer, Mehmet; Sheehan, John K.; Davis, C. William

2016-01-01

Mucin secretion is regulated by extracellular signaling molecules emanating from local, neuronal, or endocrine sources. Quantifying the rate of this secretion is important to understanding how the exocytic process is regulated, and also how goblet/mucous cells synthesize and release mucins under control and pathological conditions. Consequently, measuring mucins in a quantitatively accurate manner is the key to many experiments addressing these issues. This paper describes procedures used to determine agonist-induced mucin secretion from goblet cells in human bronchial epithelial (HBE) cell cultures. It begins with primary epithelial cell culture, offers methods for purifying MUC5AC and MUC5B mucins for standards, and describes five different microtiter plate binding assays which use various probes for mucins. A polymeric mucin-specific antibody is used in standard and sandwich ELISA formats for two assays while the others target the extensive glycosylated domains of mucins with lectin, periodate oxidation, and antibody-based probes. Comparing the data derived from the different assays applied to the same set of samples of HBE cell cultures indicates a qualitative agreement between baseline and agonist stimulated mucin release; however, the polymeric mucin-specific assays yield substantially lower values than the assays using nonspecific molecular reporters. These results indicate that the more non-specific assays are suitable to assess overall secretory responses by goblet cells, but are likely unsuited for specific measurements of polymeric mucins, per se. PMID:22259142

Serratia marcescens internalization and replication in human bladder epithelial cells

PubMed Central

Hertle, Ralf; Schwarz, Heinz

2004-01-01

Background Serratia marcescens, a frequent agent of catheterization-associated bacteriuria, strongly adheres to human bladder epithelial cells in culture. The epithelium normally provides a barrier between lumal organisms and the interstitium; the tight adhesion of bacteria to the epithelial cells can lead to internalization and subsequent lysis. However, internalisation was not shown yet for S. marcescens strains. Methods Elektronmicroscopy and the common gentamycin protection assay was used to assess intracellular bacteria. Via site directed mutagenesis, an hemolytic negative isogenic Serratia strain was generated to point out the importance of hemolysin production. Results We identified an important bacterial factor mediating the internalization of S. marcescens, and lysis of epithelial cells, as the secreted cytolysin ShlA. Microtubule filaments and actin filaments were shown to be involved in internalization. However, cytolysis of eukaryotic cells by ShlA was an interfering factor, and therefore hemolytic-negative mutants were used in subsequent experiments. Isogenic hemolysin-negative mutant strains were still adhesive, but were no longer cytotoxic, did not disrupt the cell culture monolayer, and were no longer internalized by HEp-2 and RT112 bladder epithelial cells under the conditions used for the wild-type strain. After wild-type S. marcescens became intracellular, the infected epithelial cells were lysed by extended vacuolation induced by ShlA. In late stages of vacuolation, highly motile S. marcescens cells were observed in the vacuoles. S. marcescens was also able to replicate in cultured HEp-2 cells, and replication was not dependent on hemolysin production. Conclusion The results reported here showed that the pore-forming toxin ShlA triggers microtubule-dependent invasion and is the main factor inducing lysis of the epithelial cells to release the bacteria, and therefore plays a major role in the development of S. marcescens infections. PMID:15189566

Glucocorticoid receptors in bronchial epithelial cells in asthma.

PubMed

Vachier, I; Chiappara, G; Vignola, A M; Gagliardo, R; Altieri, E; Térouanne, B; Vic, P; Bousquet, J; Godard, P; Chanez, P

1998-09-01

The expression of the glucocorticoid receptor (GR) in untreated or in steroid-dependent asthmatic patients is poorly understood. We therefore studied GR mRNA and protein levels in bronchial biopsies obtained from seven untreated asthmatic patients, seven control volunteers, and seven patients with chronic bronchitis. We also studied in bronchial epithelial cells obtained by brushing from 13 untreated asthmatics, 18 steroid-dependent asthmatics, 11 control volunteers, and 12 patients with chronic bronchitis, GR and heat shock protein 90 kD (hsp90) mRNA as well as the immunoreactivity of GR, intercellular adhesion molecule (ICAM-1), and granulocyte macrophage-colony-stimulating factor (GM-CSF). GR mRNA and protein level was similar in all subject groups in both biopsies and bronchial epithelial cells. Hsp90 mRNA level was also similar in all subject groups. ICAM-1 expression was significantly increased in bronchial epithelial cells from untreated asthmatics, but ICAM-1 was not expressed in those from steroid-dependent asthmatic patients. GM-CSF expression was significantly increased in bronchial epithelial cells from untreated and steroid-dependent asthmatic patients. GR expression within the airways is unaltered by oral long-term steroid treatment in asthma, but the expression of some but not all specific markers for asthma is modified by oral steroid.

Creation and characterization of an airway epithelial cell line for stable expression of CFTR variants

PubMed Central

Gottschalk, Laura B.; Vecchio-Pagan, Briana; Sharma, Neeraj; Han, Sangwoo T.; Franca, Arianna; Wohler, Elizabeth S.; Batista, Denise A.S.; Goff, Loyal A.; Cutting, Garry R.

2016-01-01

Background Analysis of the functional consequences and treatment response of rare CFTR variants is challenging due to the limited availability of primary airways cells. Methods A Flp recombination target (FRT) site for stable expression of CFTR was incorporated into an immortalized CF bronchial epithelial cell line (CFBE41o−). CFTR cDNA was integrated into the FRT site. Expression was evaluated by western blotting and confocal microscopy and function measured by short circuit current. RNA sequencing was used to compare the transcriptional profile of the resulting CF8Flp cell line to primary cells and tissues. Results Functional CFTR was expressed from integrated cDNA at the FRT site of the CF8Flp cell line at levels comparable to that seen in native airway cells. CF8Flp cells expressing WT-CFTR have a stable transcriptome comparable to that of primary cultured airway epithelial cells, including genes that play key roles in CFTR pathways. Conclusion CF8Flp cells provide a viable substitute for primary CF airway cells for the analysis of CFTR variants in a native context. PMID:26694805

Fibrosis of Two: Epithelial Cell-Fibroblast Interactions in Pulmonary Fibrosis

PubMed Central

Sakai, Norihiko; Tager, Andrew M.

2013-01-01

Idiopathic pulmonary fibrosis (IPF) is characterized by the progressive and ultimately fatal accumulation of fibroblasts and extracellular matrix in the lung that distorts its architecture and compromises its function. IPF is now thought to result from wound-healing processes that, although initiated to protect the host from injurious environmental stimuli, lead to pathological fibrosis due to these processes becoming aberrant or over-exuberant. Although the environmental stimuli that trigger IPF remain to be identified, recent evidence suggests that they initially injure the alveolar epithelium. Repetitive cycles of epithelial injury and resultant alveolar epithelial cell death provoke the migration, proliferation, activation and myofibroblast differentiation of fibroblasts, causing the accumulation of these cells and the extracellular matrix that they synthesize. In turn, these activated fibroblasts induce further alveolar epithelial cell injury and death, thereby creating a vicious cycle of pro-fibrotic epithelial cell-fibroblast interactions. Though other cell types certainly make important contributions, we focus here on the “pas de deux” (steps of two), or perhaps more appropriate to IPF pathogenesis, the “folie à deux” (madness of two) of epithelial cells and fibroblasts that drives the progression of pulmonary fibrosis. We describe the signaling molecules that mediate the interactions of these cell types in their “fibrosis of two”, including transforming growth factor-β, connective tissue growth factor, sonic hedgehog, prostaglandin E2, angiotensin II and reactive oxygen species. PMID:23499992

Cell confinement controls centrosome positioning and lumen initiation during epithelial morphogenesis

PubMed Central

Rodríguez-Fraticelli, Alejo E.; Auzan, Muriel; Alonso, Miguel A.; Bornens, Michel

2012-01-01

Epithelial organ morphogenesis involves sequential acquisition of apicobasal polarity by epithelial cells and development of a functional lumen. In vivo, cells perceive signals from components of the extracellular matrix (ECM), such as laminin and collagens, as well as sense physical conditions, such as matrix stiffness and cell confinement. Alteration of the mechanical properties of the ECM has been shown to promote cell migration and invasion in cancer cells, but the effects on epithelial morphogenesis have not been characterized. We analyzed the effects of cell confinement on lumen morphogenesis using a novel, micropatterned, three-dimensional (3D) Madin-Darby canine kidney cell culture method. We show that cell confinement, by controlling cell spreading, limits peripheral actin contractility and promotes centrosome positioning and lumen initiation after the first cell division. In addition, peripheral actin contractility is mediated by master kinase Par-4/LKB1 via the RhoA–Rho kinase–myosin II pathway, and inhibition of this pathway restores lumen initiation in minimally confined cells. We conclude that cell confinement controls nuclear–centrosomal orientation and lumen initiation during 3D epithelial morphogenesis. PMID:22965908

Murine hepatocellular carcinoma derived stem cells reveal epithelial-to-mesenchymal plasticity.

PubMed

Jayachandran, Aparna; Shrestha, Ritu; Dhungel, Bijay; Huang, I-Tao; Vasconcelos, Marianna Yumi Kawashima; Morrison, Brian J; Ramlogan-Steel, Charmaine A; Steel, Jason C

2017-09-26

To establish a model to enrich and characterize stem-like cells from murine normal liver and hepatocellular carcinoma (HCC) cell lines and to further investigate stem-like cell association with epithelial-to-mesenchymal transition (EMT). In this study, we utilized a stem cell conditioned serum-free medium to enrich stem-like cells from mouse HCC and normal liver cell lines, Hepa 1-6 and AML12, respectively. We isolated the 3-dimensional spheres and assessed their stemness characteristics by evaluating the RNA levels of stemness genes and a cell surface stem cell marker by quantitative reverse transcriptase-PCR (qRT-PCR). Next, we examined the relationship between stem cells and EMT using qRT-PCR. Three-dimensional spheres were enriched by culturing murine HCC and normal hepatocyte cell lines in stem cell conditioned serum-free medium supplemented with epidermal growth factor, basic fibroblast growth factor and heparin sulfate. The 3-dimensional spheres had enhanced stemness markers such as Klf4 and Bmi1 and hepatic cancer stem cell (CSC) marker Cd44 compared to parental cells grown as adherent cultures. We report that epithelial markers E-cadherin and ZO-1 were downregulated, while mesenchymal markers Vimentin and Fibronectin were upregulated in 3-dimensional spheres. The 3-dimensional spheres also exhibited changes in expression of Snai , Zeb and Twist family of EMT transcription factors. Our novel method successfully enriched stem-like cells which possessed an EMT phenotype. The isolation and characterization of murine hepatic CSCs could establish a precise target for the development of more effective therapies for HCC.

Myosin-X functions in polarized epithelial cells

PubMed Central

Liu, Katy C.; Jacobs, Damon T.; Dunn, Brian D.; Fanning, Alan S.; Cheney, Richard E.

2012-01-01

Myosin-X (Myo10) is an unconventional myosin that localizes to the tips of filopodia and has critical functions in filopodia. Although Myo10 has been studied primarily in nonpolarized, fibroblast-like cells, Myo10 is expressed in vivo in many epithelia-rich tissues, such as kidney. In this study, we investigate the localization and functions of Myo10 in polarized epithelial cells, using Madin-Darby canine kidney II cells as a model system. Calcium-switch experiments demonstrate that, during junction assembly, green fluorescent protein–Myo10 localizes to lateral membrane cell–cell contacts and to filopodia-like structures imaged by total internal reflection fluorescence on the basal surface. Knockdown of Myo10 leads to delayed recruitment of E-cadherin and ZO-1 to junctions, as well as a delay in tight junction barrier formation, as indicated by a delay in the development of peak transepithelial electrical resistance (TER). Although Myo10 knockdown cells eventually mature into monolayers with normal TER, these monolayers do exhibit increased paracellular permeability to fluorescent dextrans. Importantly, knockdown of Myo10 leads to mitotic spindle misorientation, and in three-dimensional culture, Myo10 knockdown cysts exhibit defects in lumen formation. Together these results reveal that Myo10 functions in polarized epithelial cells in junction formation, regulation of paracellular permeability, and epithelial morphogenesis. PMID:22419816

miR-1271 inhibits migration, invasion and epithelial-mesenchymal transition by targeting ZEB1 and TWIST1 in pancreatic cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Huaize; Wang, Han; Liu, Xiaoxiao

Pancreatic cancer (PC) remains one of the most lethal types of cancer in adults. The purpose of this study was to determine the role of miR-1271 in regulation of epithelial mesenchymal transition (EMT) and metastasis of pancreatic cancer cells. miR-1271 was identified to be significantly down-regulated in PC tissues by miRNA array. Also, an increase of EMT-regulators ZEB1 and TWIST1 expression level is accompanied by a decrease of miR-1271. We showed that expression of miR-1271 was significantly down-regulated in PC tissues as compared with that in normal tissues. In addition, our results showed that miR-1271 expression levels were decreased whilemore » ZEB1 and TWIST1 expression levels were increased in detected PC cell lines. Moreover, ectopic expression of miR-1271 suppressed and antagomiR-1271 promoted proliferation, migration, and invasion in SW1990 and PANC-1 cells. Bioinformatics coupled with luciferase and Western blot assays also revealed that miR-1271 inhibited expression of ZEB1 and TWIST1, which are master regulators of tumor metastasis. Our study first indicates that miR-1271 functions as a suppressor in regulating of pancreatic cancer EMT by targeting ZEB1 and TWIST1, and it promise as a therapeutic target and prognostic marker for metastatic pancreatic cancer. - Highlights: • miR-1271 is downregulated in pancreatic cancer tissues and cell lines. • miR-1271 regulates cell metastasis ability and EMT marker expression. . • miR-1271 directly targets ZEB1 and TWIST1. • ZEB1 and TWIST1 are functionally related to the effects of miR-1271.« less

Loss of γ-cytoplasmic actin triggers myofibroblast transition of human epithelial cells

PubMed Central

Lechuga, Susana; Baranwal, Somesh; Li, Chao; Naydenov, Nayden G.; Kuemmerle, John F.; Dugina, Vera; Chaponnier, Christine; Ivanov, Andrei I.

2014-01-01

Transdifferentiation of epithelial cells into mesenchymal cells and myofibroblasts plays an important role in tumor progression and tissue fibrosis. Such epithelial plasticity is accompanied by dramatic reorganizations of the actin cytoskeleton, although mechanisms underlying cytoskeletal effects on epithelial transdifferentiation remain poorly understood. In the present study, we observed that selective siRNA-mediated knockdown of γ-cytoplasmic actin (γ-CYA), but not β-cytoplasmic actin, induced epithelial-to-myofibroblast transition (EMyT) of different epithelial cells. The EMyT manifested by increased expression of α-smooth muscle actin and other contractile proteins, along with inhibition of genes responsible for cell proliferation. Induction of EMyT in γ-CYA–depleted cells depended on activation of serum response factor and its cofactors, myocardial-related transcriptional factors A and B. Loss of γ-CYA stimulated formin-mediated actin polymerization and activation of Rho GTPase, which appear to be essential for EMyT induction. Our findings demonstrate a previously unanticipated, unique role of γ-CYA in regulating epithelial phenotype and suppression of EMyT that may be essential for cell differentiation and tissue fibrosis. PMID:25143399

Immunological Targeting of Tumor Initiating Prostate Cancer Cells

DTIC Science & Technology

2014-10-01

clinically using well-accepted immuno-competent animal models. 2) Keywords: Prostate Cancer, Lymphocyte, Vaccine, Antibody 3) Overall Project Summary...castrate animals . Task 1: Identify and verify antigenic targets from CAstrate Resistant Luminal Epithelial Cells (CRLEC) (months 1-16... animals per group will be processed to derive sufficient RNA for microarray analysis; the experiment will be repeated x 3. Microarray analysis will

Human Rhinovirus Infection of Epithelial Cells Modulates Airway Smooth Muscle Migration.

PubMed

Shariff, Sami; Shelfoon, Christopher; Holden, Neil S; Traves, Suzanne L; Wiehler, Shahina; Kooi, Cora; Proud, David; Leigh, Richard

2017-06-01

Airway remodeling, a characteristic feature of asthma, begins in early life. Recurrent human rhinovirus (HRV) infections are a potential inciting stimulus for remodeling. One component of airway remodeling is an increase in airway smooth muscle cell (ASMC) mass with a greater proximity of the ASMCs to the airway epithelium. We asked whether human bronchial epithelial cells infected with HRV produced mediators that are chemotactic for ASMCs. ASMC migration was investigated using the modified Boyden Chamber and the xCELLigence Real-Time Cell Analyzer (ACEA Biosciences Inc., San Diego, CA). Multiplex bead analysis was used to measure HRV-induced epithelial chemokine release. The chemotactic effects of CCL5, CXCL8, and CXCL10 were also examined. Supernatants from HRV-infected epithelial cells caused ASMC chemotaxis. Pretreatment of ASMCs with pertussis toxin abrogated chemotaxis, as did treatment with formoterol, forskolin, or 8-bromo-cAMP. CCL5, CXCL8, and CXCL10 were the most up-regulated chemokines produced by HRV-infected airway epithelial cells. When recombinant CCL5, CXCL8, and CXCL10 were used at levels found in epithelial supernatants, they induced ASMC chemotaxis similar to that seen with epithelial cell supernatants. When examined individually, CCL5 was the most effective chemokine in causing ASMC migration, and treatment of supernatant from HRV-infected epithelial cells with anti-CCL5 antibodies significantly attenuated ASMC migration. These findings suggest that HRV-induced CCL5 can induce ASMC chemotaxis and thus may contribute to the pathogenesis of airway remodeling in patients with asthma.

Porcine circovirus type 2 displays pluripotency in cell targeting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steiner, Esther; Balmelli, Carole; Herrmann, Brigitte

Porcine circovirus type 2 (PCV2) is the causative agent of a multifactorial disease associated with immunocompromisation and co-infections. In vivo, viral DNA and antigens are found in monocytic, epithelial and endothelial cells. Of these, PCV2 replication has only been studied in monocytic cells, in which little or no replication was identified. Accordingly, PCV2 infection was studied in the endothelial cell line PEDSV.15, aortic endothelial cells, gut epithelial cells, fibrocytes and dendritic cells (DC). In all cells except DC PCV2 replication was detectable, with an increase in the levels of capsid and replicase protein. Variations in endocytic activity, virus binding andmore » uptake did not relate to the replication efficiency in a particular cell. Furthermore, replication did not correlate to cell proliferation, although a close association of viral proteins with chromatin in dividing cells was observed. No alteration in the division rate of PCV2-infected cultures was measurable, relating to replicase expression in only a small minority of the cells. In conclusion, the broad cell targeting of PCV2 offers an explanation for its widespread tissue distribution.« less

Induction of endoplasmic reticulum stress by deletion of Grp78 depletes Apc mutant intestinal epithelial stem cells.

PubMed

van Lidth de Jeude, J F; Meijer, B J; Wielenga, M C B; Spaan, C N; Baan, B; Rosekrans, S L; Meisner, S; Shen, Y H; Lee, A S; Paton, J C; Paton, A W; Muncan, V; van den Brink, G R; Heijmans, J

2017-06-15

Intestinal epithelial stem cells are highly sensitive to differentiation induced by endoplasmic reticulum (ER) stress. Colorectal cancer develops from mutated intestinal epithelial stem cells. The most frequent initiating mutation occurs in Apc, which results in hyperactivated Wnt signalling. This causes hyperproliferation and reduced sensitivity to chemotherapy, but whether these mutated stem cells are sensitive to ER stress induced differentiation remains unknown. Here we examined this by generating mice in which both Apc and ER stress repressor chaperone Grp78 can be conditionally deleted from the intestinal epithelium. For molecular studies, we used intestinal organoids derived from these mice. Homozygous loss of Apc alone resulted in crypt elongation, activation of the Wnt signature and accumulation of intestinal epithelial stem cells, as expected. This phenotype was however completely rescued on activation of ER stress by additional deletion of Grp78. In these Apc-Grp78 double mutant animals, stem cells were rapidly lost and repopulation occurred by non-mutant cells that had escaped recombination, suggesting that Apc-Grp78 double mutant stem cells had lost self-renewal capacity. Although in Apc-Grp78 double mutant mice the Wnt signature was lost, these intestines exhibited ubiquitous epithelial presence of nuclear β-catenin. This suggests that ER stress interferes with Wnt signalling downstream of nuclear β-catenin. In conclusion, our findings indicate that ER stress signalling results in loss of Apc mutated intestinal epithelial stem cells by interference with the Wnt signature. In contrast to many known inhibitors of Wnt signalling, ER stress acts downstream of β-catenin. Therefore, ER stress poses a promising target in colorectal cancers, which develop as a result of Wnt activating mutations.

Observing planar cell polarity in multiciliated mouse airway epithelial cells.

PubMed

Vladar, Eszter K; Lee, Yin Loon; Stearns, Tim; Axelrod, Jeffrey D

2015-01-01

The concerted movement of cilia propels inhaled contaminants out of the lungs, safeguarding the respiratory system from toxins, pathogens, pollutants, and allergens. Motile cilia on the multiciliated cells (MCCs) of the airway epithelium are physically oriented along the tissue axis for directional motility, which depends on the planar cell polarity (PCP) signaling pathway. The MCCs of the mouse respiratory epithelium have emerged as an important model for the study of motile ciliogenesis and the PCP signaling mechanism. Unlike other motile ciliated or planar polarized tissues, airway epithelial cells are relatively easily accessible and primary cultures faithfully model many of the essential features of the in vivo tissue. There is growing interest in understanding how cells acquire and polarize motile cilia due to the impact of mucociliary clearance on respiratory health. Here, we present methods for observing and quantifying the planar polarized orientation of motile cilia both in vivo and in primary culture airway epithelial cells. We describe how to acquire and evaluate electron and light microscopy images of ciliary ultrastructural features that reveal planar polarized orientation. Furthermore, we describe the immunofluorescence localization of PCP pathway components as a simple readout for airway epithelial planar polarization and ciliary orientation. These methods can be adapted to observe ciliary orientation in other multi- and monociliated cells and to detect PCP pathway activity in any tissue or cell type. Copyright © 2015 Elsevier Inc. All rights reserved.

Alveolar epithelial cells undergo epithelial-mesenchymal transition in acute interstitial pneumonia: a case report

PubMed Central

2014-01-01

Background Acute interstitial pneumonia is a rare interstitial lung disease that rapidly progresses to respiratory failure or death. Several studies showed that myofibroblast plays an important role in the evolution of diffuse alveolar damage, which is the typical feature of acute interstitial pneumonia. However, no evidence exists whether alveolar epithelial cells are an additional source of myofibroblasts via epithelial-mesenchymal transition in acute interstitial pneumonia. Case presentation In this report, we present a case of acute interstitial pneumonia in a previously healthy 28-year-old non-smoking woman. Chest high-resolution computed tomography scan showed bilateral and diffusely ground-glass opacification. The biopsy was performed on the fifth day of her hospitalization, and results showed manifestation of acute exudative phase of diffuse alveolar damage characterized by hyaline membrane formation. On the basis of the preliminary diagnosis of acute interstitial pneumonia, high-dose glucocorticoid was used. However, this drug showed poor clinical response and could improve the patient’s symptoms only during the early phase. The patient eventually died of respiratory dysfunction. Histological findings in autopsy were consistent with the late form of acute interstitial pneumonia. Conclusions The results in this study revealed that alveolar epithelial cells underwent epithelial-mesenchymal transition and may be an important origin of myofibroblasts in the progression of acute interstitial pneumonia. Conducting research on the transformation of alveolar epithelial cells into myofibroblasts in the lung tissue of patients with acute interstitial pneumonia may be beneficial for the treatment of this disease. However, to our knowledge, no research has been conducted on this topic. PMID:24755111

Gene expression analysis uncovers novel Hedgehog interacting protein (HHIP) effects in human bronchial epithelial cells

PubMed Central

Zhou, Xiaobo; Qiu, Weiliang; Sathirapongsasuti, J. Fah.; Cho, Michael H.; Mancini, John D.; Lao, Taotao; Thibault, Derek M.; Litonjua, Gus; Bakke, Per S.; Gulsvik, Amund; Lomas, David A.; Beaty, Terri H.; Hersh, Craig P.; Anderson, Christopher; Geigenmuller, Ute; Raby, Benjamin A.; Rennard, Stephen I.; Perrella, Mark A.; Choi, Augustine M.K.; Quackenbush, John; Silverman, Edwin K.

2013-01-01

Hedgehog Interacting Protein (HHIP) was implicated in chronic obstructive pulmonary disease (COPD) by genome-wide association studies (GWAS). However, it remains unclear how HHIP contributes to COPD pathogenesis. To identify genes regulated by HHIP, we performed gene expression microarray analysis in a human bronchial epithelial cell line (Beas-2B) stably infected with HHIP shRNAs. HHIP silencing led to differential expression of 296 genes; enrichment for variants nominally associated with COPD was found. Eighteen of the differentially expressed genes were validated by real-time PCR in Beas-2B cells. Seven of 11 validated genes tested in human COPD and control lung tissues demonstrated significant gene expression differences. Functional annotation indicated enrichment for extracellular matrix and cell growth genes. Network modeling demonstrated that the extracellular matrix and cell proliferation genes influenced by HHIP tended to be interconnected. Thus, we identified potential HHIP targets in human bronchial epithelial cells that may contribute to COPD pathogenesis. PMID:23459001

'Special K' and a Loss of Cell-To-Cell Adhesion in Proximal Tubule-Derived Epithelial Cells: Modulation of the Adherens Junction Complex by Ketamine

PubMed Central

Hills, Claire E.; Jin, Tianrong; Siamantouras, Eleftherios; Liu, Issac K-K; Jefferson, Kieran P.; Squires, Paul E.

2013-01-01

Ketamine, a mild hallucinogenic class C drug, is the fastest growing ‘party drug’ used by 16–24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24–48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1–1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and β-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGFβ, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention. PMID:24009666

Biotin-tagged platinum(iv) complexes as targeted cytostatic agents against breast cancer cells.

PubMed

Muhammad, Nafees; Sadia, Nasreen; Zhu, Chengcheng; Luo, Cheng; Guo, Zijian; Wang, Xiaoyong

2017-09-05

A biotin-guided platinum IV complex is highly cytotoxic against breast cancer cells but hypotoxic against mammary epithelial cells. The mono-biotinylated Pt IV complex is superior to the di-biotinylated one and hence a promising drug candidate for the targeted therapy of breast cancer.

Butyrate modulating effects on pro-inflammatory pathways in human intestinal epithelial cells.

PubMed

Elce, A; Amato, F; Zarrilli, F; Calignano, A; Troncone, R; Castaldo, G; Canani, R B

2017-10-13

Butyrate acts as energy source for intestinal epithelial cells and as key mediator of several immune processes, modulating gene expression mainly through histone deacetylation inhibition. Thanks to these effects, butyrate has been proposed for the treatment of many intestinal diseases. Aim of this study was to investigate the effect of butyrate on the expression of a large series of target genes encoding proteins involved in pro-inflammatory pathways. We performed quantitative real-time-PCR analysis of the expression of 86 genes encoding proteins bearing to pro-inflammatory pathways, before and after butyrate exposure, in primary epithelial cells derived from human small intestine and colon. Butyrate significantly down-regulated the expression of genes involved in inflammatory response, among which nuclear factor kappa beta, interferon-gamma, Toll like 2 receptor and tumour necrosis factor-alpha. Further confirmations of these data, including studies at protein level, would support the use of butyrate as effective therapeutic strategy in intestinal inflammatory disorders.

N-Myc Drives Neuroendocrine Prostate Cancer Initiated from Human Prostate Epithelial Cells.

PubMed

Lee, John K; Phillips, John W; Smith, Bryan A; Park, Jung Wook; Stoyanova, Tanya; McCaffrey, Erin F; Baertsch, Robert; Sokolov, Artem; Meyerowitz, Justin G; Mathis, Colleen; Cheng, Donghui; Stuart, Joshua M; Shokat, Kevan M; Gustafson, W Clay; Huang, Jiaoti; Witte, Owen N

2016-04-11

MYCN amplification and overexpression are common in neuroendocrine prostate cancer (NEPC). However, the impact of aberrant N-Myc expression in prostate tumorigenesis and the cellular origin of NEPC have not been established. We define N-Myc and activated AKT1 as oncogenic components sufficient to transform human prostate epithelial cells to prostate adenocarcinoma and NEPC with phenotypic and molecular features of aggressive, late-stage human disease. We directly show that prostate adenocarcinoma and NEPC can arise from a common epithelial clone. Further, N-Myc is required for tumor maintenance, and destabilization of N-Myc through Aurora A kinase inhibition reduces tumor burden. Our findings establish N-Myc as a driver of NEPC and a target for therapeutic intervention. Copyright © 2016 Elsevier Inc. All rights reserved.

Soluble Proteins Produced by Probiotic Bacteria Regulate Intestinal Epithelial Cell Survival and Growth

PubMed Central

YAN, FANG; CAO, HANWEI; COVER, TIMOTHY L.; WHITEHEAD, ROBERT; WASHINGTON, M. KAY; POLK, D. BRENT

2011-01-01

Background & Aims Increased inflammatory cytokine levels and intestinal epithelial cell apoptosis leading to disruption of epithelial integrity are major pathologic factors in inflammatory bowel diseases. The probiotic bacterium Lactobacillus rhamnosus GG (LGG) and factors recovered from LGG broth culture supernatant (LGG-s) prevent cytokine-induced apoptosis in human and mouse intestinal epithelial cells by regulating signaling pathways. Here, we purify and characterize 2 secreted LGG proteins that regulate intestinal epithelial cell antiapoptotic and proliferation responses. Methods LGG proteins were purified from LGG-s, analyzed, and used to generate polyclonal antibodies for immunodepletion of respective proteins from LGG-conditioned cell culture media (CM). Mouse colon epithelial cells and cultured colon explants were treated with purified proteins in the absence or presence of tumor necrosis factor (TNF). Akt activation, proliferation, tissue injury, apoptosis, and caspase-3 activation were determined. Results We purified 2 novel proteins, p75 (75 kilodaltons) and p40 (40 kilodaltons), from LGG-s. Each of these purified protein preparations activated Akt, inhibited cytokine-induced epithelial cell apoptosis, and promoted cell growth in human and mouse colon epithelial cells and cultured mouse colon explants. TNF-induced colon epithelial damage was significantly reduced by p75 and p40. Immunodepletion of p75 and p40 from LGG-CM reversed LGG-CM activation of Akt and its inhibitory effects on cytokine-induced apoptosis and loss of intestinal epithelial cells. Conclusions p75 and p40 are the first probiotic bacterial proteins demonstrated to promote intestinal epithelial homeostasis through specific signaling pathways. These findings suggest that probiotic bacterial components may be useful for preventing cytokine-mediated gastrointestinal diseases. PMID:17258729

The role of miR-200a in mammalian epithelial cell transformation

PubMed Central

Becker, Lindsey E.; Takwi, Apana Agha L.; Lu, Zhongxin; Li, Yong

2015-01-01

Cancer is a multistep disease that begins with malignant cell transformation and frequently culminates in metastasis. MicroRNAs (miRNAs) are small regulatory 21–25 nt RNA molecules and are frequently deregulated in cancer. miR-200a is a member of the miR-200 family, which are known inhibitors of the epithelial-to-mesenchymal transition. As such, the tumor-suppressive role of miR-200a in oncogenesis has been well documented; however, recent studies have found a proliferative role for this miRNA as well as a prometastatic role in the later steps of cancer progression. Little is known about the role of this miRNA in the early stages of cancer, namely, malignant cell transformation. Here, we show that miR-200a alone transforms an immortalized rat epithelial cell line, and miR-200a cooperates with Ras to enhance malignant transformation of an immortalized human epithelial cell line. Furthermore, miR-200a induces cell transformation and tumorigenesis in immunocompromised mice by cooperating with a Ras mutant that activates only the RalGEF effector pathway, but not Ras mutants activating PI3K or Raf effector pathways. This transformative ability is in accordance with miR-200a targeting Fog2 and p53 to activate Akt and directly repress p53 protein levels, respectively. These results demonstrate an oncogenic role for miR-200a and provide a specific cellular context where miR-200a acts as an oncomiR rather than a tumor suppressor by cooperating with an oncogene in malignant cell transformation. PMID:25239643

Reactivation of NCAM1 defines a subpopulation of human adult kidney epithelial cells with clonogenic and stem/progenitor properties.

PubMed

Buzhor, Ella; Omer, Dorit; Harari-Steinberg, Orit; Dotan, Zohar; Vax, Einav; Pri-Chen, Sara; Metsuyanim, Sally; Pleniceanu, Oren; Goldstein, Ronald S; Dekel, Benjamin

2013-11-01

The nephron is composed of a monolayer of epithelial cells that make up its various compartments. In development, these cells begin as mesenchyme. NCAM1, abundant in the mesenchyme and early nephron lineage, ceases to express in mature kidney epithelia. We show that, once placed in culture and released from quiescence, adult human kidney epithelial cells (hKEpCs), uniformly positive for CD24/CD133, re-express NCAM1 in a specific cell subset that attains a stem/progenitor state. Immunosorted NCAM1(+) cells overexpressed early nephron progenitor markers (PAX2, SALL1, SIX2, WT1) and acquired a mesenchymal fate, indicated by high vimentim and reduced E-cadherin levels. Gene expression and microarray analysis disclosed both a proximal tubular origin of these cells and molecules regulating epithelial-mesenchymal transition. NCAM1(+) cells generated clonal progeny when cultured in the presence of fetal kidney conditioned medium, differentiated along mesenchymal lineages but retained the unique propensity to generate epithelial kidney spheres and produce epithelial renal tissue on single-cell grafting in chick CAM and mouse. Depletion of NCAM1(+) cells from hKEpCs abrogated stemness traits in vitro. Eliminating these cells during the regenerative response that follows glycerol-induced acute tubular necrosis worsened peak renal injury in vivo. Thus, higher clone-forming and developmental capacities characterize a distinct subset of adult kidney-derived cells. The ability to influence an endogenous regenerative response via NCAM1 targeting may lead to novel therapeutics for renal diseases. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Uterine epithelial cell proliferation and endometrial hyperplasia: evidence from a mouse model.

PubMed

Gao, Yang; Li, Shu; Li, Qinglei

2014-08-01

In the uterus, epithelial cell proliferation changes during the estrous cycle and pregnancy. Uncontrolled epithelial cell proliferation results in implantation failure and/or cancer development. Transforming growth factor-β (TGF-β) signaling is a fundamental regulator of diverse biological processes and is indispensable for multiple reproductive functions. However, the in vivo role of TGF-β signaling in uterine epithelial cells remains poorly defined. We have shown that in the uterus, conditional deletion of the Type 1 receptor for TGF-β (Tgfbr1) using anti-Müllerian hormone receptor type 2 (Amhr2) Cre leads to myometrial defects. Here, we describe enhanced epithelial cell proliferation by immunostaining of Ki67 in the uteri of these mice. The aberration culminated in endometrial hyperplasia in aged females. To exclude the potential influence of ovarian steroid hormones, the proliferative status of uterine epithelial cells was assessed following ovariectomy. Increased uterine epithelial cell proliferation was also revealed in ovariectomized Tgfbr1 Amhr2-Cre conditional knockout mice. We further demonstrated that transcript levels for fibroblast growth factor 10 (Fgf10) were markedly up-regulated in Tgfbr1 Amhr2-Cre conditional knockout uteri. Consistently, treatment of primary uterine stromal cells with TGF-β1 significantly reduced Fgf10 mRNA expression. Thus, our findings suggest a potential involvement of TGFBR1-mediated signaling in the regulation of uterine epithelial cell proliferation, and provide genetic evidence supporting the role of uterine epithelial cell proliferation in the pathogenesis of endometrial hyperplasia. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Ion pump sorting in polarized renal epithelial cells.

PubMed

Caplan, M J

2001-08-01

The plasma membranes of renal epithelial cells are divided into distinct apical and basolateral domains, which contain different inventories of ion transport proteins. Without this polarity vectorial ion and fluid transport would not be possible. Little is known of the signals and mechanisms that renal epithelial cells use to establish and maintain polarized distributions of their ion transport proteins. Analysis of ion pump sorting reveals that multiple complex signals participate in determining and regulating these proteins' subcellular localizations.

Continuous tooth replacement: the possible involvement of epithelial stem cells.

PubMed

Huysseune, Ann; Thesleff, Irma

2004-06-01

Epithelial stem cells have been identified in integumental structures such as hairs and continuously growing teeth of various rodents, and in the gut. Here we propose the involvement of epithelial stem cells in the continuous tooth replacement that characterizes non-mammalian vertebrates, as exemplified by the zebrafish. Arguments are based on morphological observations of tooth renewal in the zebrafish and on the similarities between molecular control of hair and tooth formation. Dissection of the molecular cascades underlying the regulation of the epithelial stem cell niche might open perspectives for new regenerative treatment strategies in clinical dentistry. Copyright 2004 Wiley Periodicals, Inc.

MARCKS-related protein regulates cytoskeletal organization at cell-cell and cell-substrate contacts in epithelial cells.

PubMed

Van Itallie, Christina M; Tietgens, Amber Jean; Aponte, Angel; Gucek, Marjan; Cartagena-Rivera, Alexander X; Chadwick, Richard S; Anderson, James M

2018-02-02

Treatment of epithelial cells with interferon-γ and TNF-α (IFN/TNF) results in increased paracellular permeability. To identify relevant proteins mediating barrier disruption, we performed proximity-dependent biotinylation (BioID) of occludin and found that tagging of MARCKS-related protein (MRP; also known as MARCKSL1) increased ∼20-fold following IFN/TNF administration. GFP-MRP was focused at the lateral cell membrane and its overexpression potentiated the physiological response of the tight junction barrier to cytokines. However, deletion of MRP did not abrogate the cytokine responses, suggesting that MRP is not required in the occludin-dependent IFN/TNF response. Instead, our results reveal a key role for MRP in epithelial cells in control of multiple actin-based structures, likely by regulation of integrin signaling. Changes in focal adhesion organization and basal actin stress fibers in MRP-knockout (KO) cells were reminiscent of those seen in FAK-KO cells. In addition, we found alterations in cell-cell interactions in MRP-KO cells associated with increased junctional tension, suggesting that MRP may play a role in focal adhesion-adherens junction cross talk. Together, our results are consistent with a key role for MRP in cytoskeletal organization of cell contacts in epithelial cells. © 2018. Published by The Company of Biologists Ltd.

Obesity Suppresses Cell-Competition-Mediated Apical Elimination of RasV12-Transformed Cells from Epithelial Tissues.

PubMed

Sasaki, Ayana; Nagatake, Takahiro; Egami, Riku; Gu, Guoqiang; Takigawa, Ichigaku; Ikeda, Wataru; Nakatani, Tomoya; Kunisawa, Jun; Fujita, Yasuyuki

2018-04-24

Recent studies have revealed that newly emerging transformed cells are often eliminated from epithelial tissues via cell competition with the surrounding normal epithelial cells. This cancer preventive phenomenon is termed epithelial defense against cancer (EDAC). However, it remains largely unknown whether and how EDAC is diminished during carcinogenesis. In this study, using a cell competition mouse model, we show that high-fat diet (HFD) feeding substantially attenuates the frequency of apical elimination of RasV12-transformed cells from intestinal and pancreatic epithelia. This process involves both lipid metabolism and chronic inflammation. Furthermore, aspirin treatment significantly facilitates eradication of transformed cells from the epithelial tissues in HFD-fed mice. Thus, our work demonstrates that obesity can profoundly influence competitive interaction between normal and transformed cells, providing insights into cell competition and cancer preventive medicine. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

HER2 induces expression of leptin in human breast epithelial cells.

PubMed

Cha, Yujin; Kang, Youjin; Moon, Aree

2012-12-01

A close association between the obesity hormone leptin and breast cancer progression has been suggested. The present study investigated the molecular mechanism for enhanced leptin expression in breast cancer cells and its functional significance in breast cancer aggressiveness. We examined whether leptin expression level is affected by the oncoprotein human epidermal growth factor receptor2 (HER2), which is overexpressed in ∼30% of breast tumors. Here, we report, for the first time, that HER2 induces transcriptional activation of leptin in MCF10A human breast epithelial cells. We also showed that p38 mitogen-activated protein kinase signaling was involved in leptin expression induced by HER2. We showed a crucial role of leptin in the invasiveness of HER2-MCF10A cells using an siRNA molecule targeting leptin. Taken together, the results indicate a molecular link between HER2 and leptin, providing supporting evidence that leptin represents a target for breast cancer therapy. [BMB Reports 2012; 45(12): 719-723].

HER2 induces expression of leptin in human breast epithelial cells

PubMed Central

Cha, Yujin; Kang, Youjin; Moon, Aree

2012-01-01

A close association between the obesity hormone leptin and breast cancer progression has been suggested. The present study investigated the molecular mechanism for enhanced leptin expression in breast cancer cells and its functional significance in breast cancer aggressiveness. We examined whether leptin expression level is affected by the oncoprotein human epidermal growth factor receptor2 (HER2), which is overexpressed in ∼30% of breast tumors. Here, we report, for the first time, that HER2 induces transcriptional activation of leptin in MCF10A human breast epithelial cells. We also showed that p38 mitogen-activated protein kinase signaling was involved in leptin expression induced by HER2. We showed a crucial role of leptin in the invasiveness of HER2-MCF10A cells using an siRNA molecule targeting leptin. Taken together, the results indicate a molecular link between HER2 and leptin, providing supporting evidence that leptin represents a target for breast cancer therapy. [BMB Reports 2012; 45(12): 719-723] PMID:23261058

Asbestos exposure induces alveolar epithelial cell plasticity through MAPK/Erk signaling.

PubMed

Tamminen, Jenni A; Myllärniemi, Marjukka; Hyytiäinen, Marko; Keski-Oja, Jorma; Koli, Katri

2012-07-01

The inhalation of asbestos fibers is considered to be highly harmful, and lead to fibrotic and/or malignant disease. Epithelial-to-mesenchymal transition (EMT) is a common pathogenic mechanism in asbestos associated fibrotic (asbestosis) and malignant lung diseases. The characterization of molecular pathways contributing to EMT may provide new possibilities for prognostic and therapeutic applications. The role of asbestos as an inducer of EMT has not been previously characterized. We exposed cultured human lung epithelial cells to crocidolite asbestos and analyzed alterations in the expression of epithelial and mesenchymal marker proteins and cell morphology. Asbestos was found to induce downregulation of E-cadherin protein levels in A549 lung carcinoma cells in 2-dimensional (2D) and 3D cultures. Similar findings were made in primary small airway epithelial cells cultured in 3D conditions where the cells retained alveolar type II cell phenotype. A549 cells also exhibited loss of cell-cell contacts, actin reorganization and expression of α-smooth muscle actin (α-SMA) in 2D cultures. These phenotypic changes were not associated with increased transforming growth factor (TGF)-β signaling activity. MAPK/Erk signaling pathway was found to mediate asbestos-induced downregulation of E-cadherin and alterations in cell morphology. Our results suggest that asbestos can induce epithelial plasticity, which can be interfered by blocking the MAPK/Erk kinase activity. Copyright © 2012 Wiley Periodicals, Inc.