Impaired TRIM16-Mediated Lysophagy in Chronic Obstructive Pulmonary Disease Pathogenesis.

Insufficient autophagic degradation has been implicated in accelerated cellular senescence during chronic obstructive pulmonary disease (COPD) pathogenesis. Aging-linked and cigarette smoke (CS)-induced functional deterioration of lysosomes may be associated with impaired autophagy. Lysosomal membrane permeabilization (LMP) is indicative of damaged lysosomes. Galectin-3 and tripartite motif protein (TRIM) 16 play a cooperative role in recognizing LMP and inducing lysophagy, a lysosome-selective autophagy, to maintain lysosome function. In this study, we sought to examine the role of TRIM16-mediated lysophagy in regulating CS-induced LMP and cellular senescence during COPD pathogenesis by using human bronchial epithelial cells and lung tissues. CS extract (CSE) induced lysosomal damage via LMP, as detected by galectin-3 accumulation. Autophagy was responsible for modulating LMP and lysosome function during CSE exposure. TRIM16 was involved in CSE-induced lysophagy, with impaired lysophagy associated with lysosomal dysfunction and accelerated cellular senescence. Airway epithelial cells in COPD lungs showed an increase in lipofuscin, aggresome and galectin-3 puncta, reflecting accumulation of lysosomal damage with concomitantly reduced TRIM16 expression levels. Human bronchial epithelial cells isolated from COPD patients showed reduced TRIM16 but increased galectin-3, and a negative correlation between TRIM16 and galectin-3 protein levels was demonstrated. Damaged lysosomes with LMP are accumulated in epithelial cells in COPD lungs, which can be at least partly attributed to impaired TRIM16-mediated lysophagy. Increased LMP in lung epithelial cells may be responsible for COPD pathogenesis through the enhancement of cellular senescence.

Chaperone-Mediated Autophagy Suppresses Apoptosis via Regulation of the Unfolded Protein Response during Chronic Obstructive Pulmonary Disease Pathogenesis.

Cigarette smoke (CS) induces accumulation of misfolded proteins with concomitantly enhanced unfolded protein response (UPR). Increased apoptosis linked to UPR has been demonstrated in chronic obstructive pulmonary disease (COPD) pathogenesis. Chaperone-mediated autophagy (CMA) is a type of selective autophagy for lysosomal degradation of proteins with the KFERQ peptide motif. CMA has been implicated in not only maintaining nutritional homeostasis but also adapting the cell to stressed conditions. Although recent papers have shown functional cross-talk between UPR and CMA, mechanistic implications for CMA in COPD pathogenesis, especially in association with CS-evoked UPR, remain obscure. In this study, we sought to examine the role of CMA in regulating CS-induced apoptosis linked to UPR during COPD pathogenesis using human bronchial epithelial cells (HBEC) and lung tissues. CS extract (CSE) induced LAMP2A expression and CMA activation through a Nrf2-dependent manner in HBEC. LAMP2A knockdown and the subsequent CMA inhibition enhanced UPR, including CHOP expression, and was accompanied by increased apoptosis during CSE exposure, which was reversed by LAMP2A overexpression. Immunohistochemistry showed that Nrf2 and LAMP2A levels were reduced in small airway epithelial cells in COPD compared with non-COPD lungs. Both Nrf2 and LAMP2A levels were significantly reduced in HBEC isolated from COPD, whereas LAMP2A levels in HBEC were positively correlated with pulmonary function tests. These findings suggest the existence of functional cross-talk between CMA and UPR during CSE exposure and also that impaired CMA may be causally associated with COPD pathogenesis through enhanced UPR-mediated apoptosis in epithelial cells.

Involvement of GPx4-Regulated Lipid Peroxidation in Idiopathic Pulmonary Fibrosis Pathogenesis.

The imbalanced redox status in lung has been widely implicated in idiopathic pulmonary fibrosis (IPF) pathogenesis. To regulate redox status, hydrogen peroxide must be adequately reduced to water by glutathione peroxidases (GPx). Among GPx isoforms, GPx4 is a unique antioxidant enzyme that can directly reduce phospholipid hydroperoxide. Increased lipid peroxidation products have been demonstrated in IPF lungs, suggesting the participation of imbalanced lipid peroxidation in IPF pathogenesis, which can be modulated by GPx4. In this study, we sought to examine the involvement of GPx4-modulated lipid peroxidation in regulating TGF-ß-induced myofibroblast differentiation. Bleomycin-induced lung fibrosis development in mouse models with genetic manipulation of GPx4 were examined. Immunohistochemical evaluations for GPx4 and lipid peroxidation were performed in IPF lung tissues. Immunohistochemical evaluations showed reduced GPx4 expression levels accompanied by increased 4-hydroxy-2-nonenal in fibroblastic focus in IPF lungs. TGF-ß-induced myofibroblast differentiation was enhanced by GPx4 knockdown with concomitantly enhanced lipid peroxidation and SMAD2/SMAD3 signaling. Heterozygous GPx4-deficient mice showed enhancement of bleomycin-induced lung fibrosis, which was attenuated in GPx4-transgenic mice in association with lipid peroxidation and SMAD signaling. Regulating lipid peroxidation by Trolox showed efficient attenuation of bleomycin-induced lung fibrosis development. These findings suggest that increased lipid peroxidation resulting from reduced GPx4 expression levels may be causally associated with lung fibrosis development through enhanced TGF-ß signaling linked to myofibroblast accumulation of fibroblastic focus formation during IPF pathogenesis. It is likely that regulating lipid peroxidation caused by reduced GPx4 can be a promising target for an antifibrotic modality of treatment for IPF.

Involvement of Lamin B1 Reduction in Accelerated Cellular Senescence during Chronic Obstructive Pulmonary Disease Pathogenesis.

Downregulation of lamin B1 has been recognized as a crucial step for development of full senescence. Accelerated cellular senescence linked to mechanistic target of rapamycin kinase (MTOR) signaling and accumulation of mitochondrial damage has been implicated in chronic obstructive pulmonary disease (COPD) pathogenesis. We hypothesized that lamin B1 protein levels are reduced in COPD lungs, contributing to the process of cigarette smoke (CS)-induced cellular senescence via dysregulation of MTOR and mitochondrial integrity. To illuminate the role of lamin B1 in COPD pathogenesis, lamin B1 protein levels, MTOR activation, mitochondrial mass, and cellular senescence were evaluated in CS extract (CSE)-treated human bronchial epithelial cells (HBEC), CS-exposed mice, and COPD lungs. We showed that lamin B1 was reduced by exposure to CSE and that autophagy was responsible for lamin B1 degradation in HBEC. Lamin B1 reduction was linked to MTOR activation through DEP domain-containing MTOR-interacting protein (DEPTOR) downregulation, resulting in accelerated cellular senescence. Aberrant MTOR activation was associated with increased mitochondrial mass, which can be attributed to peroxisome proliferator-activated receptor γ coactivator-1ß-mediated mitochondrial biogenesis. CS-exposed mouse lungs and COPD lungs also showed reduced lamin B1 and DEPTOR protein levels, along with MTOR activation accompanied by increased mitochondrial mass and cellular senescence. Antidiabetic metformin prevented CSE-induced HBEC senescence and mitochondrial accumulation via increased DEPTOR expression. These findings suggest that lamin B1 reduction is not only a hallmark of lung aging but is also involved in the progression of cellular senescence during COPD pathogenesis through aberrant MTOR signaling.

Prognostic impact of preoperative FDG-PET positive lymph nodes in lung cancer.

BACKGROUND: 2-[18F] Fluoro-D-deoxyglucose positron emission tomography (FDG-PET) is an appropriate diagnostic procedure for staging lung cancer. However, accurate evaluation of lymph node (LN) metastases by PET is controversial owing to false-positive/-negative FDG uptake results. The prognostic significance of both false-negative and false-positive LNs on FDG-PET remains to be determined. METHODS: A total of 235 patients with lung cancer were retrospectively analyzed. Maximum standardized uptake values (SUVmax) of the lymph nodes were compared with pathological LN metastases to correlate PET findings with clinicopathological variables and patients' outcomes. RESULTS: When SUVmax ≥ 4 was defined as PET-positive for LN metastasis, sensitivity, specificity, and accuracy were 46.0%, 79.5%, and 72.3%, respectively. False-negative cases and pathological n0 cases were significantly younger, had primary tumors that were smaller or lower SUVmax, and adenocarcinomas compared with false-positive and pathological n+ cases. The difference in survival time between patients with abnormal FDG uptake in the LN and those without was larger than that between pathological LN metastases and no pathological metastases in patients with adenocarcinoma. Multivariate analysis by the Cox proportional hazard model identified smoker, EGFR/ALK negative and LN positive on PET as significant adverse prognostic factors, rather than pathological n-stage. CONCLUSIONS: Abnormal FDG uptake in the LN is an important prognostic factor. Increased glucose metabolism on FDG-PET appears to be a more efficient postoperative prognostic marker than pathological n-stage in patients with lung cancer.

Chaperone-mediated autophagy receptor modulates tumor growth and chemoresistance in non-small cell lung cancer.

Chaperone-mediated autophagy (CMA) is a lysosomal degradation pathway of selective soluble proteins. Lysosome-associated membrane protein type 2a (LAMP2A) is the key receptor protein of CMA; downregulation of LAMP2A leads to CMA blockade. Although CMA activation has been involved in cancer growth, CMA status and functions in non-small cell lung cancer (NSCLC) by focusing on the roles in regulating chemosensitivity remain to be clarified. In this study, we found that LAMP2A expression is elevated in NSCLC cell lines and patient's tumors, conferring poor survival and platinum resistance in NSCLC patients. LAMP2A knockdown in NSCLC cells suppressed cell proliferation and colony formation and increased the sensitivity to chemotherapeutic drugs in vitro. Furthermore, we found that intrinsic apoptosis signaling is the mechanism of cell death involved with CMA blockade. Remarkably, LAMP2A knockdown repressed tumorigenicity and sensitized the tumors to cisplatin treatment in NSCLC-bearing mice. Our discoveries suggest that LAMP2A is involved in the regulation of cancer malignant phenotypes and represents a promising new target against chemoresistant NSCLC.

Pirfenidone inhibits myofibroblast differentiation and lung fibrosis development during insufficient mitophagy.

BACKGROUND: Pirfenidone (PFD) is an anti-fibrotic agent used to treat idiopathic pulmonary fibrosis (IPF), but its precise mechanism of action remains elusive. Accumulation of profibrotic myofibroblasts is a crucial process for fibrotic remodeling in IPF. Recent findings show participation of autophagy/mitophagy, part of the lysosomal degradation machinery, in IPF pathogenesis. Mitophagy has been implicated in myofibroblast differentiation through regulating mitochondrial reactive oxygen species (ROS)-mediated platelet-derived growth factor receptor (PDGFR) activation. In this study, the effect of PFD on autophagy/mitophagy activation in lung fibroblasts (LF) was evaluated, specifically the anti-fibrotic property of PFD for modulation of myofibroblast differentiation during insufficient mitophagy. METHODS: Transforming growth factor-ß (TGF-ß)-induced or ATG5, ATG7, and PARK2 knockdown-mediated myofibroblast differentiation in LF were used for in vitro models. The anti-fibrotic role of PFD was examined in a bleomycin (BLM)-induced lung fibrosis model using PARK2 knockout (KO) mice. RESULTS: We found that PFD induced autophagy/mitophagy activation via enhanced PARK2 expression, which was partly involved in the inhibition of myofibroblast differentiation in the presence of TGF-ß. PFD inhibited the myofibroblast differentiation induced by PARK2 knockdown by reducing mitochondrial ROS and PDGFR-PI3K-Akt activation. BLM-treated PARK2 KO mice demonstrated augmentation of lung fibrosis and oxidative modifications compared to those of BLM-treated wild type mice, which were efficiently attenuated by PFD. CONCLUSIONS: These results suggest that PFD induces PARK2-mediated mitophagy and also inhibits lung fibrosis development in the setting of insufficient mitophagy, which may at least partly explain the anti-fibrotic mechanisms of PFD for IPF treatment.

Involvement of Parkin-mediated mitophagy in the pathogenesis of chronic obstructive pulmonary disease-related sarcopenia.

BACKGROUND: Sarcopenia is characterized by the loss of skeletal muscle mass and strength and is associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). Cigarette smoke (CS) exposure, a major cause for COPD, induces mitochondrial damage, which has been implicated in sarcopenia pathogenesis. The current study sought to examine the involvement of insufficient Parkin-mediated mitophagy, a mitochondrion-selective autophagy, in the mechanisms by which dysfunctional mitochondria accumulate with excessive reactive oxygen species (ROS) production in the development of COPD-related sarcopenia. METHODS: The involvement of Parkin-mediated mitophagy was examined using in vitro models of myotube formation, in vivo CS-exposure model using Parkin-/- mice, and human muscle samples from patients with COPD-related sarcopenia. RESULTS: Cigarette smoke extract (CSE) induced myotube atrophy with concomitant 30% reduction in Parkin expression levels (P < 0.05). Parkin-mediated mitophagy regulated myotube atrophy by modulating mitochondrial damage and mitochondrial ROS production. Increased mitochondrial ROS was responsible for myotube atrophy by activating Muscle Ring Finger 1 (MuRF-1)-mediated myosin heavy chain (MHC) degradation. Parkin-/- mice with prolonged CS exposure showed enhanced limb muscle atrophy with a 31.7% reduction in limb muscle weights (P < 0.01) and 2.3 times greater MuRF-1 expression (P < 0.01) compared with wild-type mice with concomitant accumulation of damaged mitochondria and oxidative modifications in 4HNE expression. Patients with COPD-related sarcopenia exhibited significantly reduced Parkin but increased MuRF-1 protein levels (35% lower and 2.5 times greater protein levels compared with control patients, P < 0.01 and P < 0.05, respectively) and damaged mitochondria accumulation demonstrated in muscles. Electric pulse stimulation-induced muscle contraction prevented CSE-induced MHC reduction by maintaining Parkin levels in myotubes. CONCLUSIONS: Taken together, COPD-related sarcopenia can be attributed to insufficient Parkin-mediated mitophagy and increased mitochondrial ROS causing enhanced muscle atrophy through MuRF-1 activation, which may be at least partly preventable through optimal physical exercise.

Clinicopathologic Significance of False-Positive Lymph Node Status on FDG-PET in Lung Cancer.

INTRODUCTION: 2-[18F] Fluoro-d-deoxyglucose (FDG) positron emission tomography (PET) is a relevant diagnostic procedure for staging lung cancer. However, accurate evaluation of lymph node metastases by PET is controversial because of false-positive FDG uptake. PATIENTS AND METHODS: A total of 245 patients with lung cancer were retrospectively analyzed. Standardized maximum uptake values (SUVmax) of the primary tumor and lymph nodes were compared to pathologic lymph node metastases to correlate PET findings with clinicopathologic variables and patient outcomes. RESULTS: The SUVmax values of metastatic lymph nodes were significantly higher than those of lymph nodes without metastases (P = .0036). When SUVmax ≥ 4 was defined as PET positive for metastasis, the sensitivity, specificity, and accuracy were 48.1%, 79.8%, and 73.1%, respectively. Multivariate logistic regression analysis showed that age > 75 years, bilateral hilar FDG uptake, and no lymph node swelling were significant factors related to false-positive lymph node metastases. Smoking status, FDG uptake in the primary tumor, and concurrent lung diseases were not significant factors. CONCLUSION: Metastatic lymph nodes show higher FDG uptake than false-positive lymph nodes, and older patient age, bilateral hilar FDG uptake, and no swollen nodes are associated with no metastases. Patients with lymph node metastases have worse survival than those with false-positive FDG-PET findings. However, abnormal FDG uptake in the lymph node is an important prognostic factor.

Therapeutic effect of linac-based stereotactic radiotherapy with a micro-multileaf collimator for the treatment of patients with brain metastases from lung cancer.

OBJECTIVE: To assess the efficacy of hypofractionated linac-based stereotactic radiotherapy with a micro-multileaf collimator (mMLC) in lung cancer patients with brain metastases. METHODS: Seventy-eight lesions of brain metastases in 49 lung cancer patients treated by stereotactic radiotherapy between September 2003 and December 2006 were analyzed. In the treatment planning, the planning target volume (PTV) was defined as an enhanced lesion plus 3 mm margin. A total dose of 39-42 Gy in three fractions was delivered to the isocenters of the PTV. RESULTS: The median survival time after stereotactic radiotherapy was 17.4 months. The 1- and 2-year survival rates were 61% and 32%, respectively. The presence of extracranial tumors, the pre-treatment performance status, and the Radiation Therapy Oncology Group recursive partitioning analysis class were significant prognostic factors. The 1- and 2-year local recurrence rates were 14% and 17%, respectively, with no serious acute toxic effect. Injuries involving brain necrosis were observed in six patients. New brain metastases or meningeal carcinomatosis was seen in more than half of the patients following treatment with stereotactic radiotherapy. CONCLUSIONS: Hypofactionated stereotactic radiotherapy with mMLC is considered to be an effective and safe modality for the treatment of brain metastases in lung cancer patients.

Prostaglandin E-Major Urinary Metabolite (PGE-MUM) as a Tumor Marker for Lung Adenocarcinoma.

Background: Prostaglandin E2 (PGE2) is metabolized to prostaglandin E-major urinary metabolite (PGE-MUM). Enhanced cyclooxygenase-2 (COX-2) expression demonstrated in lung adenocarcinoma indicates increased PGE-MUM levels in patients with lung adenocarcinoma. Objectives: We aimed to elucidate the clinical usefulness of measuring PGE-MUM as an indicator of tumor burden in patients with lung adenocarcinoma. Methods: PGE-MUM was measured by a radioimmunoassay in control healthy volunteers (n = 124) and patients with lung adenocarcinoma (n = 54). Associations between PGE-MUM levels and clinical characteristics of the patients (including lung cancer stage and TNM factors (T: Tumor, N: Node, M: Metastasis) were examined. Results: PGE-MUM levels were significantly elevated in patients with lung adenocarcinoma. A PGE-MUM level of 14.9 µg/g∙Cr showed 70.4% sensitivity and 67.7% specificity for the diagnosis of lung adenocarcinoma. PGE-MUM levels tended to be positively correlated with cancer progression as determined by the TNM staging system. Advanced stage (stage III, stage IV, and recurrence) was significantly associated with high PGE-MUM levels by logistic regression analysis. No apparent correlation was demonstrated between PGE-MUM and carcinoma embryonic antigen (CEA) levels. Conclusions: PGE-MUM can be a promising biomarker reflecting the systemic tumor burden of lung adenocarcinoma.

Involvement of cigarette smoke-induced epithelial cell ferroptosis in COPD pathogenesis.

Ferroptosis is a necrotic form of regulated cell death (RCD) mediated by phospholipid peroxidation in association with free iron-mediated Fenton reactions. Disrupted iron homeostasis resulting in excessive oxidative stress has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Here, we demonstrate the involvement of ferroptosis in COPD pathogenesis. Our in vivo and in vitro models show labile iron accumulation and enhanced lipid peroxidation with concomitant non-apoptotic cell death during cigarette smoke (CS) exposure, which are negatively regulated by GPx4 activity. Treatment with deferoxamine and ferrostatin-1, in addition to GPx4 knockdown, illuminate the role of ferroptosis in CS-treated lung epithelial cells. NCOA4-mediated ferritin selective autophagy (ferritinophagy) is initiated during ferritin degradation in response to CS treatment. CS exposure models, using both GPx4-deficient and overexpressing mice, clarify the pivotal role of GPx4-regulated cell death during COPD. These findings support a role for cigarette smoke-induced ferroptosis in the pathogenesis of COPD.

PRKN-regulated mitophagy and cellular senescence during COPD pathogenesis.

Cigarette smoke (CS)-induced accumulation of mitochondrial damage has been widely implicated in chronic obstructive pulmonary disease (COPD) pathogenesis. Mitophagy plays a crucial role in eliminating damaged mitochondria, and is governed by the PINK1 (PTEN induced putative protein kinase 1)-PRKN (parkin RBR E3 ubiquitin protein ligase) pathway. Although both increased PINK1 and reduced PRKN have been implicated in COPD pathogenesis in association with mitophagy, there are conflicting reports for the role of mitophagy in COPD progression. To clarify the involvement of PRKN-regulated mitophagy in COPD pathogenesis, prkn knockout (KO) mouse models were used. To illuminate how PINK1 and PRKN regulate mitophagy in relation to CS-induced mitochondrial damage and cellular senescence, overexpression and knockdown experiments were performed in airway epithelial cells (AEC). In comparison to wild-type mice, prkn KO mice demonstrated enhanced airway wall thickening with emphysematous changes following CS exposure. AEC in CS-exposed prkn KO mice showed accumulation of damaged mitochondria and increased oxidative modifications accompanied by accelerated cellular senescence. In vitro experiments showed PRKN overexpression was sufficient to induce mitophagy during CSE exposure even in the setting of reduced PINK1 protein levels, resulting in attenuation of mitochondrial ROS production and cellular senescence. Conversely PINK1 overexpression failed to recover impaired mitophagy caused by PRKN knockdown, indicating that PRKN protein levels can be the rate-limiting factor in PINK1-PRKN-mediated mitophagy during CSE exposure. These results suggest that PRKN levels may play a pivotal role in COPD pathogenesis by regulating mitophagy, suggesting that PRKN induction could mitigate the progression of COPD. Abbreviations: AD: Alzheimer disease; AEC: airway epithelial cells; BALF: bronchoalveolar lavage fluid; AKT: AKT serine/threonine kinase; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; CDKN1A: cyclin dependent kinase inhibitor 1A; CDKN2A: cyclin dependent kinase inhibitor 2A; COPD: chronic obstructive pulmonary disease; CS: cigarette smoke; CSE: CS extract; CXCL1: C-X-C motif chemokine ligand 1; CXCL8: C-X-C motif chemokine ligand 8; HBEC: human bronchial epithelial cells; 4-HNE: 4-hydroxynonenal; IL: interleukin; KO: knockout; LF: lung fibroblasts; LPS: lipopolysaccharide; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; 8-OHdG: 8-hydroxy-2'-deoxyguanosine; OPTN: optineurin; PRKN: parkin RBR E3 ubiquitin protein ligase; PCD: programmed cell death; PFD: pirfenidone; PIK3C: phosphatidylinositol-4:5-bisphosphate 3-kinase catalytic subunit; PINK1: PTEN induced putative kinase 1; PTEN: phosphatase and tensin homolog; RA: rheumatoid arthritis; ROS: reactive oxygen species; SA-GLB1/ß-Gal: senescence-associated-galactosidase, beta 1; SASP: senescence-associated secretory phenotype; SNP: single nucleotide polymorphism; TNF: tumor necrosis factor.

Binding of sialyl Lewis X antigen to lectin-like receptors on NK cells induces cytotoxicity and tyrosine phosphorylation of a 17-kDa protein.

BACKGROUND: Natural killer (NK) cells mediate cytotoxicity through cell-surface receptors including lectin-like receptors. We have investigated whether sialyl Lewis X (sLe(X)) antigen, Neu5Acalpha2,3Galbeta1,4(Fucalpha1,3) GlcNAc-R, can bind to the lectin-like receptors on human NK-derived KHYG cells, using transferrin secreted by human hepatoma-derived HepG2 cells (Hep-TF), whose N-glycans are rich in alpha1,3-fucosylated bi-, tri-, and tetra-antennary type complexes, and commercially available human transferrin (Nor-TF), which is comprised of bi-antennary N-glycans without alpha1,3-fucosylation. RESULTS: High sLeX-expressing erythroleukemia-derived K562 cells isolated from fucosyltransferase-3-transfected cells were 2.5-fold more susceptible than wild-type K562 cells to KHYG cells. Fluorescein isothiocyanate (FITC)-labeled Hep-TF bound 1.8-fold more strongly to KHYG cells than did FITC-labeled Nor-TF; the binding was suppressed by treatment with anti-NKG2D, anti-NKG2C, anti-CD94 and anti-CD161 antibodies. FITC-labeled Hep-TF bound more strongly to human monocyte-derived U937 cells transfected with NKG2D and CD94 than to wild-type U937 cells. Moreover, tyrosine phosphorylation of a 17-kDa protein in the KHYG cells was enhanced by incubation on a Hep-TF coated plate and treatment with an anti-NKG2D antibody, but not by a Nor-TF coated plate and an anti-CD94 antibody. CONCLUSION: The interaction of sLe(X) antigen with lectin-like receptors on NK cells induces cytotoxicity that is mediated through a tyrosine-phosphorylated 17-kDa protein.

Azithromycin attenuates myofibroblast differentiation and lung fibrosis development through proteasomal degradation of NOX4.

Accumulation of profibrotic myofibroblasts is involved in the process of fibrosis development during idiopathic pulmonary fibrosis (IPF) pathogenesis. TGFB (transforming growth factor ß) is one of the major profibrotic cytokines for myofibroblast differentiation and NOX4 (NADPH oxidase 4) has an essential role in TGFB-mediated cell signaling. Azithromycin (AZM), a second-generation antibacterial macrolide, has a pleiotropic effect on cellular processes including proteostasis. Hence, we hypothesized that AZM may regulate NOX4 levels by modulating proteostasis machineries, resulting in inhibition of TGFB-associated lung fibrosis development. Human lung fibroblasts (LF) were used to evaluate TGFB-induced myofibroblast differentiation. With respect to NOX4 regulation via proteostasis, assays for macroautophagy/autophagy, the unfolded protein response (UPR), and proteasome activity were performed. The potential anti-fibrotic property of AZM was examined by using bleomycin (BLM)-induced lung fibrosis mouse models. TGFB-induced NOX4 and myofibroblast differentiation were clearly inhibited by AZM treatment in LF. AZM-mediated NOX4 reduction was restored by treatment with MG132, a proteasome inhibitor. AZM inhibited autophagy and enhanced the UPR. Autophagy inhibition by AZM was linked to ubiquitination of NOX4 via increased protein levels of STUB1 (STIP1 homology and U-box containing protein 1), an E3 ubiquitin ligase. An increased UPR by AZM was associated with enhanced proteasome activity. AZM suppressed lung fibrosis development induced by BLM with concomitantly reduced NOX4 protein levels and enhanced proteasome activation. These results suggest that AZM suppresses NOX4 by promoting proteasomal degradation, resulting in inhibition of TGFB-induced myofibroblast differentiation and lung fibrosis development. AZM may be a candidate for the treatment of the fibrotic lung disease IPF.

[A case of esophageal arterial bleeding in which transcatheter arterial embolization was useful for hemostasis].

We report a case of hemostatic treatment by transcatheter arterial embolization (TAE) of the left gastric artery and a branch of the left bronchial artery for oozing hemorrhage in the lower esophagus, because of incomplete endoscopic hemostasis. A 52-year-old woman with systemic lupus erythematosus was previously admitted three times to our hospital for endoscopic treatment of hemorrhage in the lower esophageal lesions. The procedure of TAE for esophageal hemorrhage seems to be a useful treatment for cases of incomplete endoscopic hemostasis.

Evaluation of the Effect of Tumor Position on Standardized Uptake Value Using Time-of-Flight Reconstruction and Point Spread Function.

OBJECTIVES: The present study was conducted to examine whether the standardized uptake value (SUV) may be affected by the spatial position of a lesion in the radial direction on positron emission tomography (PET) images, obtained via two methods based on time-of-flight (TOF) reconstruction and point spread function (PSF). METHODS: A cylinder phantom with the sphere (30 mm diameter), located in the center was used in this study. Fluorine-18 fluorodeoxyglucose (18F-FDG) concentrations of 5.3 kBq/ml and 21.2 kBq/ml were used for the background in the cylinder phantom and the central sphere respectively. By the use of TOF and PSF, SUV max and SUV mean were determined while moving the phantom in a horizontal direction (X direction) from the center of field of view (FOV: 0 mm) at 50, 100, 150 and 200 mm positions, respectively. Furthermore, we examined 41 patients (23 male, 18 female, mean age: 68±11.2 years) with lymph node tumors, who had undergone 18F-FDG PET examinations. The distance of each lymph node from FOV center was measured, based on the clinical images. RESULTS: As the distance of a lesion from the FOV center exceeded 100 mm, the value of SUV max , which was obtained with the cylinder phantom, was overestimated, while SUV mean by TOF and/or PSF was underestimated. Based on the clinical examinations, the average volume of interest was 8.5 cm3. Concomitant use of PSF increased SUV max and SUV mean by 27.9% and 2.8%, respectively. However, size of VOI and distance from the FOV center did not affect SUV max or SUV mean in clinical examinations. CONCLUSION: The reliability of SUV quantification by TOF and/or PSF decreased, when the tumor was located at a 100 mm distance (or farther) from the center of FOV. In clinical examinations, if the lymph node was located within 100 mm distance from the center of FOV, SUV remained stable within a constantly increasing range by use of both TOF and PSF. We conclude that, use of both TOF and PSF may be helpful.

Evaluation of muscle metabolic activity in the lower limb of a transfemoral amputee using a prosthesis by using (18)F-FDG PET imaging--an application of PET imaging to rehabilitation.

This study used FDG PET to evaluate the lower limb muscles metabolic activities of transfemoral amputees during walking with prostheses. As a preliminary study, FDG PET was applied for two normal adult volunteers to evaluate muscle activity in the lower extremities after gait exercise. This same method was applied for two amputee volunteers with prostheses. We found that FDG accumulated more in both gluteus medius muscles after gait exercise compared to other muscles in normal adult volunteers. In the skilled amputee volunteer, FDG uptake increased in the adductor and gluteus medius in the amputated side, while in the unskilled the adductor, gluteus maximus, and gluteus medius showed increased FDG uptake only in the normal side. This result suggests that basic metabolic changes such as an increase in oxidative metabolism and less reliance on glycolytic activity would occur as a result of skeletal muscle training in amputees.

Analysis of complete response by MRI following neoadjuvant chemotherapy predicts pathological tumor responses differently for molecular subtypes of breast cancer.

In the present study, clinical tumor response following neoadjuvant chemotherapy (NAC) was diagnosed by magnetic resonance imaging (MRI) and clinicopathological factors, including molecular subtypes at baseline, were analyzed for correlations with pathological tumor responses. In addition, clinicopathological factors were analyzed for a correlation with the MRI capacity to predict pathological complete response (pCR). Clinical tumor response evaluated by MRI following NAC was determined as a clinical CR (cCR) or a residual tumor. cCR was confirmed if no gadolinium enhancement or an enhancement equal to or less than that of glandular tissue was observed in any phase of the MRI. Pathological tumor responses following NAC were classified into grades 0 (no change) to 3 (no residual invasive cancer) according to criteria of the Japanese Breast Cancer Society. pCR was defined as grade 3 in the present study. Of 264 cases of invasive breast cancer in 260 patients (4 synchronous bilateral breast cancer cases), 59 (22%) were diagnosed by MRI following NAC as cCR and 98 (37%) were pathologically diagnosed as pCR. In terms of predicting pCR by MRI, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were 44, 90, 73, 73 and 73%, respectively. Tumor size, hormone receptor status, human epidermal growth factor receptor 2 (HER2) status, molecular subtype and histological type were significantly correlated with pathological tumor responses. pCR rates increased in the following order: luminal/HER2-negative (14%), luminal/HER2-positive (32%), triple-negative (46%) and non-luminal/HER2-positive (73%) tumors. Sensitivity and specificity were the highest (60 and 100%, respectively) in triple-negative tumors. PPV decreased in the following order: triple-negative (100%), non-luminal/HER2-positive (92%), luminal/HER2-positive (46%) and luminal/HER2-negative (33%) tumors. In conclusion, MRI evaluation is useful for predicting pCR following NAC, particularly for triple-negative tumors.

Concurrent chemoradiotherapy followed by consolidation chemotherapy with bi-weekly docetaxel and carboplatin for stage III unresectable, non-small-cell lung cancer: clinical application of a protocol used in a previous phase II study.

PURPOSE: To assess the clinical applicability of a protocol evaluated in a previously reported phase II study of concurrent chemoradiotherapy followed by consolidation chemotherapy with bi-weekly docetaxel and carboplatin in patients with stage III, unresectable, non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: Between January 2000 and March 2006, 116 previously untreated patients with histologically proven, stage III NSCLC were treated with concurrent chemoradiotherapy. Radiation therapy was administered in 2-Gy daily fractions to a total dose of 60 Gy in combination with docetaxel, 30 mg/m(2), and carboplatin at an area under the curve value of 3 every 2 weeks during and after radiation therapy. RESULTS: The median survival time for the entire group was 25.5 months. The actuarial 2-year and 5-year overall survival rates were 53% and 31%, respectively. The 3-year cause-specific survival rate was 60% in patients with stage IIIA disease, whereas it was 35% in patients with stage IIIB disease (p = 0.007). The actuarial 2-year and 5-year local control rates were 62% and 55%, respectively. Acute hematologic toxicities of Grade ≥3 severity were observed in 20.7% of patients, while radiation pneumonitis and esophagitis of Grade ≥3 severity were observed in 2.6% and 1.7% of patients, respectively. CONCLUSIONS: The feasibility of the protocol used in the previous phase II study was reconfirmed in this series, and excellent treatment results were achieved.