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Rochester, MN, United States

Plataki M.,Thoracic Disease Research Unit | Hubmayr R.D.,Thoracic Disease Research Unit
Expert Review of Respiratory Medicine | Year: 2010

Although mechanical ventilation (MV) is a life-saving intervention for patients with acute respiratory distress syndrome (ARDS), it can aggravate or cause lung injury, known as ventilator-induced lung injury (VILI). The biophysical characteristics of heterogeneously injured ARDS lungs increase the parenchymal stress associated with breathing, which is further aggravated by MV. Cells, in particular those lining the capillaries, airways and alveoli, transform this strain into chemical signals (mechanotransduction). The interaction of reparative and injurious mechanotransductive pathways leads to VILI. Several attempts have been made to identify clinical surrogate measures of lung stress/strain (e.g., density changes in chest computed tomography, lower and upper inflection points of the pressure-volume curve, plateau pressure and inflammatory cytokine levels) that could be used to titrate MV. However, uncertainty about the topographical distribution of stress relative to that of the susceptibility of the cells and tissues to injury makes the existence of a single 'global stress/strain injury threshold doubtful. © 2010 Expert Reviews Ltd.

Nallet-Staub F.,Institute Curie | Nallet-Staub F.,French Institute of Health and Medical Research | Nallet-Staub F.,French National Center for Scientific Research | Nallet-Staub F.,University Paris - Sud | And 22 more authors.
Developmental Cell | Year: 2015

Cell-cell contacts inhibit cell growth and proliferation in part by activating the Hippo pathway that drives the phosphorylation and nuclear exclusion of the transcriptional coactivators YAP and TAZ. Cell density and Hippo signaling have also been reported to block transforming growth factor β (TGF-β) responses, based on the ability of phospho-YAP/TAZ to sequester TGF-β-activated SMAD complexes in the cytoplasm. Herein, we provide evidence that epithelial cell polarization interferes with TGF-β signaling well upstream and independent of cytoplasmic YAP/TAZ. Rather, polarized basolateral presentation of TGF-β receptors I and II deprives apically delivered TGF-β of access to its receptors. Basolateral ligand delivery nonetheless remains entirely effective to induce TGF-β responses. These data demonstrate that cell-type-specific inhibition of TGF-β signaling by cell density is restricted to polarized epithelial cells and reflects the polarized distribution of TGF-β receptors, which thus affects SMAD activation irrespective of Hippo pathway activation. © 2015 Elsevier Inc.

Silva F.,University of Santiago de Chile | Cisternas M.,University of Santiago de Chile | Specks U.,Thoracic Disease Research Unit
Current Rheumatology Reports | Year: 2012

ANCA-associated vasculitides (AAV) are small vessel systemic vasculitis syndromes associated with the potential for high morbidity and mortality. This group includes granulomatosis with polyangiitis (Wegener's, GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (Churg-Strauss, EGPA). The standard treatment consists of a combination of glucocorticoids and potent immunosuppressant drugs. These have broad mechanisms of action as well as important adverse effects. Efforts have been made to investigate novel agents with better-defined and narrower mechanisms of action, such as biologics, including TNF-α blockers. Etanercept, a well-known TNF-α blocker evaluated for GPA in the Wegener's Granulomatosis Etanercept Trial (WGET), was associated with an increase in the development of solid malignancies in comparison to placebo during that trial period. A 5-year follow-up after the WGET trial showed a sustained increase in incidence of solid malignancies, but this could no longer be solely attributed to etanercept exposure. These studies raised concerns about the use of the family of TNF-α blockers in AAV. Here, we review the evidence about the association between therapeutic inhibition of tumor necrosis factor (TNF-α) by etanercept and other TNF-α blockers with the development of solid malignancies in GPA and other AAV. © Springer Science+Business Media, LLC 2012.

Bhattacharyya S.,Rochester College | Singh R.D.,Rochester College | Singh R.D.,Thoracic Disease Research Unit | Pagano R.,Thoracic Disease Research Unit | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2012

On the right path: The mechanisms of endocytosis of cetuximab (C225) and its nanoconjugates have been elucidated in a pancreatic cancer cell line. By using gold nanoparticles as a scaffold, it is possible to switch the pathway for endocytosis from a Dyn-2-dependent caveolar mechanism to Cdc42-dependent pinocytosis/phagocytosis. Tailoring endocytotic mechanisms may enable specific intracellular pathways to be targeted. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Basal E.,Mayo Medical School | Ayeni T.,Mayo Medical School | Zhang Q.,Mayo Medical School | Langstraat C.,Mayo Medical School | And 5 more authors.
Current Molecular Medicine | Year: 2016

The MIS pathway is a potential therapeutic target in epithelial ovarian cancer (EOC): signaling requires both type II (T2R) and type I receptors (T1R), and results in growth inhibition. MISR2 is expressed in EOC, but the prevalence and relative contributions of candidate T1R remain unknown. We sought to: a) determine expression of T1R in EOC; b) assess impact of T1R expression with clinical outcomes; c) verify MIS-dependent Smad signaling and growth inhibition in primary EOC cell cultures. Tissue microarrays (TMA) were developed for analysis of T1Rs (ALK2/3/6) and MISR2 expression. Primary cell cultures were initiated from ascites harvested at surgery which were used to characterize response to MIS. TMA’s from 311 primary cancers demonstrated the most common receptor combinations were: MISR2+/ALK2+3+6+ (36%); MISR2+/ALK2+3+6- (34%); MISR2-/ALK2+3+6- (18%); and MISR2-/ALK2+3+6+ (6.8%). No differences in overall survival (OS) were noted between combinations. The ALK6 receptor was least often expressed T1R and was associated with lower OS in early stage disease only (p =0.03). Most primary cell cultures expressed MISR2 (14/22 (63.6%)): 95% of these express ALK 2 and ALK3, whereas 54.5% expressed ALK6. MIS-dependent Smad phosphorylation was seen in the majority of cultures (75%). Treatment with MIS led to reduced cell viability at an average of 71% (range: 57-87%) in primary cultures. MIS signaling is dependent upon the presence of both MISR2 and specific T1R. In the majority of EOC, the T1R required for MIS-dependent signaling are present and such cells demonstrate appropriate response to MIS. © 2016 Bentham Science Publishers.

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