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Epithelial Morphology (epithelial + morphology)
Selected AbstractsUpregulated claudin-1 expression confers resistance to cell death of nasopharyngeal carcinoma cellsINTERNATIONAL JOURNAL OF CANCER, Issue 6 2010Jeng-Woei Lee Abstract Accumulating evidence reveals that aberrant expression of claudins manifests in various tumors; however, their biological functions are poorly understood. Here, we report on the elevated expression of claudin-1 in nasopharyngeal carcinoma (NPC) cell lines under serum deprivation or fluorouracil (5-FU) treatment. Interestingly, an increase in expression of claudin-1 considerably reduced apoptosis rather than enhancing cell proliferation. However, claudin-1 expression and activity were unaffected by external stimuli or Akt and NF-,B activation. Notably, predominant cytoplasmic and nuclear localization of claudin-1 in NPC cells reflected the aforementioned feature. On the other hand, loss of epithelial morphology and E-cadherin expression was associated with serum withdrawal in NPC cells. Interestingly, restoration of E-cadherin inhibited the protein elevation and antiapoptotic activity of claudin-1. In conclusion, our data demonstrate the regulation and novel biological function of claudin-1 and indicate the important role of claudin-1 in NPC tumorigenesis. [source] Induction of hepatic differentiation of mouse bone marrow stromal stem cells by the histone deacetylase inhibitor VPAJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 8b 2009Ye Chen Abstract Bone marrow stromal stem cells (BMSSCs) may have potential to differentiate in vitro and in vivo into hepatocytes. Here, we investigated the effects of valproic acid (VPA) involved in epigenetic modification, a direct inhibitor of histone deacetylase, on hepatic differentiation of mouse BMSSCs. Following the treatment of 2.5 mM VPA for 72 hrs, the in vitro expanded, highly purified and functionally active mouse BMSSCs from bone marrow were either exposed to some well-defined cytokines and growth factors in a sequential way (fibroblast growth factor-4 [FGF-4], followed by HGF, and HGF + OSM + ITS + dexamethasone, resembling the order of secretion during liver embryogenesis) or transplanted (caudal vein) in mice submitted to a protocol of chronic injury (chronic i.p. injection of CCl4). Additional exposure of the cells to VPA considerably improved the in vitro differentiation, as demonstrated by a more homogeneous cell population exhibited epithelial morphology, increasing expression of hepatic special genes and enhanced hepatic functions. Further more, in vivo results indicate that the pre-treatment of VPA significantly increased the homing efficiency of BMSSCs to the site of liver injury and, additionally, for supporting hepatic differentiation as well as in vitro. We have demonstrated the usefulness of VPA in the transdifferentiation of BMSSCs into hepatocytes both in vitro and in vivo, and regulation of fibroblast growth factor receptors (FGFRs) and c-Met gene expression through post-translational modification of core histones might be the primary initiating event for these effects. This mode could be helpful for liver engineering and clinical therapy. [source] Isolation of epithelial stem cells from dermis by a three-dimensional culture system,JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2006Reinhold J. Medina Abstract Skin is a representative self-renewing tissue containing stem cells. Although many attempts have been made to define and isolate skin-derived stem cells, establishment of a simple and reliable isolation procedure remains a goal to be achieved. Here, we report the isolation of cells having stem cell properties from mouse embryonic skin using a simple selection method based on an assumption that stem cells may grow in an anchorage-independent manner. We inoculated single cell suspensions prepared from mouse embryonic dermis into a temperature-sensitive gel and propagated the resulting colonies in a monolayer culture. The cells named dermis-derived epithelial progenitor-1 (DEEP) showed epithelial morphology and grew rapidly to a more than 200 population doubling level over a period of 250 days. When the cells were kept confluent, they spontaneously formed spheroids and continuously grew even in spheroids. Immunostaining revealed that all of the clones were positive for the expression of cytokeratin-8, ,18, ,19, and E-cadherin and negative for the expression of cytokeratin-1, ,5, ,6, ,14, ,20, vimentin, nestin, a ckit. Furthermore, they expressed epithelial stem cell markers such as p63, integrin ,1, and S100A6. On exposure to TGF, in culture, some of DEEP-1 cells expressed ,-smooth muscle actin. When the cells were transplanted into various organs of adult SCID mice, a part of the inoculated cell population acquired neural, hepatic, and renal cell properties. These results indicate that the cells we isolated were of epithelial stem cell origin and that our new approach is useful for isolation of multipotent stem cells from skin tissues. J. Cell. Biochem. 98: 174,184, 2006. © 2006 Wiley-Liss, Inc. [source] Vinculin, VASP, and profilin are coordinately regulated during actin remodeling in epithelial cells, which requires de novo protein synthesis and protein kinase signal transduction pathwaysJOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2004Margaret P. Quinlan Transformation progression of epithelial cells involves alterations in their morphology, polarity, and adhesive characteristics, all of which are associated with the loss and/or reorganization of actin structures. To identify the underlying mechanism of formation of the adhesion-dependent, circumferential actin network, the expression and localization of the actin binding and regulating proteins (ABPs), vinculin, VASP, and profilin were evaluated. Experimental depolarization of epithelial cells results in the loss of normal F-actin structures and the transient upregulation of vinculin, VASP, and profilin. This response is due to the loss of cell,cell, and not cell,substrate interactions, since cells that no longer express focal adhesions or stress fibers are still sensitive to changes in adhesion and manifest this in the altered profile of expression of these ABPs. Transient upregulation is dependent upon de novo protein synthesis, and protein kinase-, but not phosphatase-sensitive signal transduction pathway(s). Inhibition of the synthesis of these proteins is accompanied by dephosphorylation of the ribosomal S6 protein, but does not involve inhibition of the PI3-kinase-Akt-mTOR pathway. Constitutive expression of VASP results in altered cell morphology and adhesion and F-actin and vinculin structures. V12rac1 expressing epithelial cells are constitutively nonadhesive, malignantly transformed, and constitutively express high levels of these ABPs, with altered subcellular localizations. Transformation suppression is accompanied by the restoration of normal levels of the three ABPs, actin structures, adhesion, and epithelial morphology. Thus, vinculin, VASP, and profilin are coordinately regulated by signal transduction pathways that effect a translational response. Additionally, their expression profile maybe indicative of the adhesion and transformation status of epithelial cells. J. Cell. Physiol. 200: 277,290, 2004. © 2004 Wiley-Liss, Inc. [source] 4131: Pathologic epithelial and anterior corneal nerve morphology in congenital aniridic keratopathyACTA OPHTHALMOLOGICA, Issue 2010P FAGERHOLM Purpose To document corneal morphology in Swedish families with congenital aniridia. Methods Detailed ophthalmic examinations were conducted in a number of affected and unaffected members. Digital slit lamp photography, anterior segment optical coherence tomography (ASOCT) and in-vivo confocal microscopy (IVCM) examinations were performed bilaterally to document corneal morphology. Results Affected family members presented with different stages of aniridic keratopathy, with a corneal appearance varying from totally transparent to opaque and highly vascularised. Increased corneal thickness in affected members, particularly those with severe keratopathy, was noted by ASOCT. By IVCM, opaque corneas were characterized by active vessels and dense inflammatory cell infiltration. In corneas with milder keratopathy, pathologic epithelial findings included epithelial pleomorphism, focal epithelial opacities, and an absence of limbal epithelial crypts and focal stromal projections at the limbus. Nerves of the anterior cornea exhibited several distinct features, including an unusually close association of subbasal nerves with epithelial cells, an unusually high subbasal nerve density with highly branched nerves, and a prominent whorl region. Additionally, abnormally dense and tortuous anterior stromal nerves, attached to stromal keratocytes, were noted in unaffected members. Conclusion Altered epithelial morphology and a vigorous innervation of the anterior cornea were the most pronounced corneal findings in family members with milder forms of aniridic keratopathy. Further findings confirmed the known increase in corneal thickness and limbal stem cell abnormality in aniridia. [source] Detection of osmoprotective effect of topical compatible solutes on ocular surface epitheliaACTA OPHTHALMOLOGICA, Issue 2009R CALIENNO Purpose Inflamation and hyperosmolarity play an important role in generating dry-eye related damage on the ocular surface. A new approach is the use of topical compatible solutes (CS) to induce osmoprotective effect on ocular surface epithelia. Aim of this study was to evaluate the osmoprotective action of topical CS on ocular surface in dry-eye patients. Methods We evaluated 48 eyes of 24 dry-eye patients, current users of artificial tears. At baseline they underwent impression cytology (IC) and immunoflurescence staining to detect expression of inflammatory cytokines linked with hyperosmolarity in ocular surface epithelia. In vivo confocal microscopy (IVCM) of corneal and conjunctival surface was performed and epithelial morphology and inflammatory cells infiltration were evaluated. Patients started topical treatment with methilcellulose and CS in one randomly selected eye, while the fellow eye continued previous eye drops.IC and IVCM were performed after 30,60 and 90 days. Results At baseline IVCM and IC results were comparable in both eyes . At 90 days IVCM showed a significant improvement in epithelial regularity in treated eyes while in control group no significant changes were observed.IC evidenced a significant reduction of inflammatory cytokines between baseline time and day 60, stable till the end of follow-up, while in control group no significant changes were observed. Conclusion The use of topical CS can improve epithelial regularity and reduce ocular surface inflammation in dry-eye syndrome. [source] | |||||||||||||