@article{CeteciCeteciZanuccoetal.2012, author = {Ceteci, Fatih and Ceteci, Semra and Zanucco, Emanuele and Thakur, Chitra and Becker, Matthias and El-Nikhely, Nefertiti and Fink, Ludger and Seeger, Werner and Savai, Rajkumar and Rapp, Ulf R.}, title = {E-Cadherin Controls Bronchiolar Progenitor Cells and Onset of Preneoplastic Lesions in Mice}, series = {Neoplasia}, volume = {14}, journal = {Neoplasia}, number = {12}, doi = {10.1593/neo.121088}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135407}, pages = {1164-1177}, year = {2012}, abstract = {Although progenitor cells of the conducting airway have been spatially localized and some insights have been gained regarding their molecular phenotype, relatively little is known about the mechanisms regulating their maintenance, activation, and differentiation. This study investigates the potential roles of E-cadherin in mouse Clara cells, as these cells were shown to represent the progenitor/stem cells of the conducting airways and have been implicated as the cell of origin of human non-small cell lung cancer. Postnatal inactivation of E-cadherin affected Clara cell differentiation and compromised airway regeneration under injury conditions. In steady-state adult lung, overexpression of the dominant negative E-cadherin led to an expansion of the bronchiolar stem cells and decreased differentiation concomitant with canonical Wnt signaling activation. Expansion of the bronchiolar stem cell pool was associated with an incessant proliferation of neuroepithelial body-associated Clara cells that ultimately gave rise to bronchiolar hyperplasia. Despite progressive hyperplasia, only a minority of the mice developed pulmonary solid tumors, suggesting that the loss of E-cadherin function leads to tumor formation when additional mutations are sustained. The present study reveals that E-cadherin plays a critical role in the regulation of proliferation and homeostasis of the epithelial cells lining the conducting airways.}, language = {en} } @article{PonnuswamySchroettleOstermeieretal.2012, author = {Ponnuswamy, Padmapriya and Schr{\"o}ttle, Angelika and Ostermeier, Eva and Gr{\"u}ner, Sabine and Huang, Paul L. and Ertl, Georg and Hoffmann, Ulrich and Nieswandt, Bernhard and Kuhlencordt, Peter J.}, title = {eNOS Protects from Atherosclerosis Despite Relevant Superoxide Production by the Enzyme in apoE\(^{-/-}\) Mice}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0030193}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134866}, pages = {e30193}, year = {2012}, abstract = {Background: All three nitric oxide synthase (NOS) isoforms are expressed in atherosclerotic plaques. NOS enzymes in general catalyse NO production. However, under conditions of substrate and cofactor deficiency, the enzyme directly catalyse superoxide formation. Considering this alternative chemistry, the effects of NOS on key events in spontaneous hyperlipidemia driven atherosclerosis have not been investigated yet. Here, we evaluate how endothelial nitric oxide synthase (eNOS) modulates leukocyte/endothelial-(L/E) and platelet/endothelial-(P/E) interactions in atherosclerosis and the production of nitric oxide (NO) and superoxide by the enzyme. Principal Findings: Intravital microscopy (IVM) of carotid arteries revealed significantly increased L/E-interactions in apolipoproteinE/eNOS double knockout mice (apoE\(^{-/-}\)/eNOS\(^{-/-}\)), while P/E-interactions did not differ, compared to apoE\(^{-/-}\). eNOS deficiency increased macrophage infiltration in carotid arteries and vascular cell adhesion molecule-1 (VCAM-1) expression, both in endothelial and smooth muscle cells. Despite the expression of other NOS isoforms (inducible NOS, iNOS and neuronal NOS, nNOS) in plaques, Electron Spin Resonance (ESR) measurements of NO showed significant contribution of eNOS to total circulating and vascular wall NO production. Pharmacological inhibition and genetic deletion of eNOS reduced vascular superoxide production, indicating uncoupling of the enzyme in apoE\(^{-/-}\) vessels. Conclusion: Overt plaque formation, increased vascular inflammation and L/E-interactions are associated with significant reduction of superoxide production in apoE\(^{-/-}\)/eNOS\(^{-/-}\) vessels. Therefore, lack of eNOS does not cause an automatic increase in oxidative stress. Uncoupling of eNOS occurs in apoE\(^{-/-}\) atherosclerosis but does not negate the enzyme's strong protective effects.}, language = {en} }