Glutathione S-transferase M1 modulates allergen-induced NF-κB activation in asthmatic airway epithelium.

BACKGROUND: Glutathione S-transferase M1 (GSTM1) is a phase II enzyme and regulator of inflammatory signaling in airway epithelial cells. We have found upregulation of neutrophilic airway inflammation in atopic asthmatics expressing GSTM1 gene (GSTM1+) compared to GSTM1null asthmatics. We hypothesized that GSTM1 modulates NF-κB activation in bronchial epithelium in atopic asthmatics. We determined regulation of allergen-induced NF-κB activation in bronchial epithelium by GSTM1 in human atopic asthmatics in vivo. METHODS: Endobronchial biopsies and bronchoalveolar lavage fluid samples were collected from 13 GSTM1+ and 12 GSTM1null human atopic asthmatics at baseline and 24 h after segmental allergen challenge. A quantitative analysis of NF-κB activation in airway epithelium was accomplished using a polyclonal antibody against the phosphorylated p65 component of NF-κB. Elastase-positive neutrophils in the bronchial wall were quantified. RESULTS: Postallergen neutrophilia in airway subepithelium and epithelial lining fluid was greater in GSTM1+ compared to GSTM1null asthmatics. Airway eosinophilia was similar in GSTM1+ and GSTM1null asthmatics. Allergen-provoked NF-κB induction in bronchial epithelium was significantly greater in GSTM1+ compared to GSTM1null asthmatics. Activation of NF-κB activation in airway epithelial cells correlated with interleukin-8 concentrations and absolute neutrophil numbers in bronchoalveolar lavage fluid in GSTM1+ but not GSTM1null asthmatics. CONCLUSIONS: Allergen-induced neutrophilic airway inflammation in GSTM1+ asthmatics is associated with NF-κB activation in airway epithelial cells in vivo. These novel data provide a potential mechanism of the genomic link between GSTM1 polymorphism and airway neutrophilia in atopic asthma.

Autoimmune pancreatitis results from loss of TGFbeta signalling in S100A4-positive dendritic cells.

BACKGROUND AND AIMS: Autoimmune pancreatitis (AIP) is a poorly understood human disease affecting the exocrine pancreas. The goal of the present study was to elucidate the pathogenic mechanisms underlying pancreatic autoimmunity in a murine disease model. METHODS: A transgenic mouse with an S100A4/fibroblast-specific protein 1 (FSP1) Cre-mediated conditional knockout of the transforming growth factor beta (TGFbeta) type II receptor, termed Tgfbr2(fspKO), was used to determine the direct role of TGFbeta in S100A4(+) cells. Immunohistochemical studies suggested that Tgfbr2(fspKO) mice develop mouse AIP (mAIP) characterised by interlobular ductal inflammatory infiltrates and pancreatic autoantibody production. Fluorescence-activated cell sorting (FACS)-isolated dendritic cells (DCs) from diseased pancreata were verified to have S100A4-Cre-mediated DNA recombination. RESULTS: The Tgfbr2(fspKO) mice spontaneously developed mAIP by 6 weeks of age. DCs were confirmed to express S100A4, a previously reported protein expressed by fibroblasts. Adoptive transfer of bone marrow-derived DCs from Tgfbr2(fspKO) mice into 2-week-old syngenic wild-type C57BL/6 mice resulted in reproduction of pancreatitis within 6 weeks. Similar adoptive transfer of wild-type DCs had no effect on pancreas pathology of the host mice. The inability to induce pancreatitis by adoptive transfer of Tgfbr2(fspKO) DCs in adult mice suggested a developmental event in mAIP pathogenesis. Tgfbr2(fspKO) DCs undergo elevated maturation in response to antigen and increased activation of naïve CD4-positive T cells. CONCLUSION: The development of mAIP in the Tgfbr2(fspKO) mouse model illustrates the role of TGFbeta in maintaining myeloid DC immune tolerance. The loss of immune tolerance in myeloid S100A4(+) DCs can mediate mAIP and may explain some aspects of AIP disease pathogenesis.

The nuclear factor kappa-B pathway in airway epithelium regulates neutrophil recruitment and host defence following Pseudomonas aeruginosa infection.

Pseudomonas aeruginosa pneumonia usually results from a deficit of the innate immune system. To investigate whether inflammatory signalling by airway epithelial cells provides a pivotal line of defence against P. aeruginosa infection, we utilized two separate lines of inducible transgenic mice that express a constitutive activator of the nuclear factor kappa-B (NF-kappaB) pathway (IKTA) or a dominant inhibitor of NF-kappaB (DNTA) in airway epithelial cells. Compared with control mice, IKTA mice showed an enhanced host response to P. aeruginosa infection with greater neutrophil influx into the lungs, increased expression of Glu-Leu-Arg-positive (ELR(+)) CXC chemokines macrophage inflammatory protein-2 and keratinocyte chemoattractant (KC), superior bacterial clearance and improved survival at 24 h after infection. Neutrophil depletion abrogated the improvement in host defence identified in IKTA mice. In contrast, DNTA mice showed impaired responses to P. aeruginosa infection with higher bacterial colony counts in the lungs, decreased neutrophilic lung inflammation and lower levels of KC in lung lavage fluid. DNTA mice given recombinant KC at the time of P. aeruginosa infection demonstrated improved neutrophil recruitment to the lungs and enhanced bacterial clearance. Our data indicate that the NF-kappaB pathway in airway epithelial cells plays an essential role in defence against P. aeruginosa through generation of CXC chemokines and recruitment of neutrophils.

Conditional regulation of cyclooxygenase-2 in tracheobronchial epithelial cells modulates pulmonary immunity.

Cyclooxygenase-2 (COX-2) gene expression in the lung is induced in pathological conditions such as asthma and pneumonia; however, the exact impact of COX-2 gene expression in the airway in regulating inflammatory and immunological response in the lung is not understood. To define a physiological role of inducible COX-2 in airway epithelial cells, we developed a novel line of transgenic mice, referred to as CycloOxygenase-2 TransActivated (COTA) mice, that overexpress a COX-2 transgene in the distribution of the CC-10 promoter in response to doxycycline. In response to doxycycline treatment, COX-2 expression was increased in airway epithelium of COTA mice and whole lung tissue contained a three- to sevenfold increase in prostaglandin E(2) (PGE(2)), prostaglandin D(2) (PGD(2)) thromboxane B(2) (TXB(2)) and 6-Keto prostaglandin F(2alpha) (PGF(2alpha)) compared to wild-type and untreated COTA mice. Interestingly, primary mouse tracheal epithelial cells from COTA mice produced only PGE(2) by doxycycline-induced COX-2 activation, providing an indication of cellular specificity in terms of mediator production. In the ovalbumin model, in which doxycycline was given at the sensitization stage, there was an increase in interleukin (IL)-4 level in lung tissue from COTA mice compared to untreated COTA and wild-type mice. In addition, COTA mice that were treated with doxycycline had impaired clearance of Pseudomonas aeruginosa pneumonia compared to wild-type mice. COX-2 gene expression in airway epithelial cells has an important role in determining immunological response to infectious and allergic agents.

Induction of endotoxin tolerance depletes nuclear factor-kappaB and suppresses its activation in rat alveolar macrophages.

To investigate the mechanism of endotoxin tolerance in macrophages, a rat alveolar macrophage cell line (NR8383) was rendered endotoxin tolerant by treatment with endotoxin at 40 ng/mL for 48 h. This treatment induced a state of tolerance such that subsequent exposure to high-dose endotoxin (5 microg/mL) resulted in decreased production of macrophage inflammatory protein-2, tumor necrosis factor alpha, and nitric oxide compared to endotoxin-sensitive cells. Suppressed mediator production by endotoxin-tolerant cells was associated with impaired activation of nuclear factor-kappaB (NF-kappaB) in response to treatment with 5 microg/mL of endotoxin. This impairment of NF-kappaB activation was found to be associated with depletion of latent NF-kappaB (both RelA and p50) in the cytoplasm of endotoxin-tolerant cells. These data suggest that a mechanism of endotoxin tolerance is depletion of RelA/p50, which could limit the amount of NF-kappaB available for activation by subsequent stimuli and thereby inhibit transcription of NF-kappaB-dependent genes. Limiting NF-kappaB-dependent inflammatory gene transcription by inducing endotoxin tolerance is a potential therapeutic strategy for diseases where excessive production of inflammatory mediators leads to tissue injury.

Redox regulation of nuclear factor kappa B: therapeutic potential for attenuating inflammatory responses.

Nuclear factor kappa B (NF-kappaB) is a protein transcription factor that is required for maximal transcription of a wide array of pro-inflammatory mediators that are involved in the pathogenesis of stroke. The purpose of this review article is to describe what is known about the molecular biology of NF NF-kappaB and to review current understanding of the interaction between reactive oxygen species (ROS) in NF-kappaB. ROS seem to play a duel role by participating in the NF-kappaB activation cascade and by directly modulating DNA binding affinity. Exogenous and endogenous antioxidants are effective in blocking activation of NF-kappaB and preventing the consequences of pro-inflammatory gene expression. Phase II enzymes either directly or indirectly play a major in vivo role in minimizing oxidative stress by scavenging peroxides, peroxide breakdown products and dicarbonyls and in regeneration of lipid peroxidation chain-breaker, vitamin E. Dietary phase II enzyme inducers have been demonstrated to increase phase II enzyme activities in a variety of tissues. These data, together, suggest that phase II enzyme inducers could have therapeutic value for ameliorating inflammatory conditions.

Oxidative stress and NF-kappaB activation: correlation in patients following allogeneic bone marrow transplantation.

Although in vitro data has linked reactive oxygen species (ROS) to activation of nuclear factor kappaB (NF-kappaB), little data exist regarding this relationship in human disease. We hypothesized that bone marrow transplantation (BMT) would impart a degree of oxidative stress that might lead to in vivo activation of the redox-sensitive transcription factor NF-kappaB. Because NF-kappaB regulates transcription of many proinflammatory mediators, we reasoned that activation of NF-kappaB might contribute to the development of transplant-related complications. To evaluate NF-kappaB activation in humans, we measured NF-kappaB binding activity in nuclear extracts of bronchoalveolar lavage (BAL) cells obtained before and after allogeneic bone marrow transplantation (BMT) in 7 patients. Changes in BAL cell NF-kappaB binding activity were compared with changes in urinary F2-isoprostane concentration, an indicator of in vivo free radical-catalyzed lipid peroxidation. Although the extent of in vivo lipid peroxidation has substantial interindividual variability over time, we found a strong correlation between the pre/post-BMT ratio of urinary isoprostane concentrations and pre/post-BMT ratio of NF-kappaB binding activity in BAL cells, R = 0.96, p = 0.0005). This correlation is selective, because no relationship was found between the transcription factor CREB and urinary F2-isoprostane excretion. Although limited by the small number of patients studied, our data link oxidant stress to NF-kappaB activation in human alveolar macrophages following BMT. It is possible that such interactions may contribute to the clinical course after BMT by affecting transcription of proinflammatory genes.

Molecular targets for modulating lung inflammation and injury.

The inflammatory response of the lung and airways is one of the main targets for tile development of new therapies for variety of disorders including the acute respiratory distress syndrome, cystic fibrosis, idiopathic pulmonary fibrosis, and chronic obstructive pulmonary disease. Over the last decade our understanding of the molecular biology of the inflammatory response has advanced considerably and has opened up new avenues for therapeutic intervention. Furthermore, the mechanism of action of many of the existing anti-inflammatory agents has been revealed by this burgeoning information. Here, we discuss the functions and therapeutic potential of molecules that might prove promising as targets for treatment of inflammatory lung diseases. These possible molecular targets include cell surface proteins/receptors [toll like receptors (TLRs), triggering receptors expressed on myeloid cells (TREMs), and syndecans)], transcription factors [NF-kappaB, AP-1, PU.1, and high mobility group box 1 (HMGB1)], and regulatory proteins [macrophage migration inhibitory factor (MIF), granulocyte macrophage colony stimulating factor (GM-CSF), cyclooxygenase 2 (COX-2), heme oxygenase 1 (HO-1)].

The role of nuclear factor-kappa B in pulmonary diseases.

Nuclear factor-kappa B (NF-kappaB) is a family of DNA-binding protein factors that are required for transcription of most proinflammatory molecules, including adhesion molecules, enzymes, cytokines, and chemokines. NF-kappaB activation seems to be a key early event in a variety of cell and animal model systems developed to elucidate the pathobiology of lung diseases. The purpose of this short review is to describe what is known about the molecular biology of NF-kappaB and to review information that implicates NF-kappaB in the pathogenesis of lung disease, including ARDS, systemic inflammatory response syndrome, asthma, respiratory viral infections, occupational and environmental lung disease, and cystic fibrosis.

Nuclear factor kappa B: a pivotal role in the systemic inflammatory response syndrome and new target for therapy.

NF-kappaB is an important transcription factor complex that appears to play a fundamental role in regulating acute inflammation through activation of the cytokine cascade and production of other pro-inflammatory mediators. There is increasing evidence that NF-kappaB is important in the pathobiology of disease states such as SIRS, MODS and ARDS; therefore, therapeutic interventions aimed at limiting NF-kappaB activation and down-regulating production of inflammatory mediators could prove to be beneficial in decreasing host-derived tissue injury and organ dysfunction. Specific interventions that hold promise for suppressing NF-kappaB activation include the use of antioxidants, inhibition of NIK and the IKK signalsome, treatment with proteasome inhibitors, induction of endotoxin tolerance and, possibly the use of corticosteroids in selected patients.

Acute lung injury after hepatic cryoablation: correlation with NF-kappa B activation and cytokine production.

BACKGROUND: Previous clinical reports have documented multisystem organ injury after hepatic cryoablation. We hypothesized that hepatic cryosurgery, but not partial hepatectomy, induces a systemic inflammatory response characterized by distant organ injury and overproduction of nuclear factor kappa B (NF-kappa B)-dependent, proinflammatory cytokines. METHODS: In this study, rats underwent either cryoablation of 35% of liver parenchyma or a similar resection of left hepatic tissue. Serum tumor necrosis factor-alpha and macrophage inflammatory protein-2 levels and NF-kappa B activation were assessed by electrophoretic mobility shift assay at 30 minutes 1, 2, 6, and 24 hours after either procedure. RESULTS: Cryoablation of 35% of liver (n = 22 rats) resulted in lung injury and a 45% mortality rate within 24 hours of surgery, whereas 7% treated with 35% hepatectomy (n = 15 rats) died during the 24 hours after surgery (P < .05, cryoablation vs hepatectomy). Serum tumor necrosis factor-alpha and macrophage inflammatory protein-2 levels were markedly increased in rats (n = 10 rats) 1 hour after hepatic cryoablation compared with rats that underwent partial hepatectomy (P < .005). We evaluated NF-kappa B activation by electrophoretic mobility shift assay in nuclear extracts of liver and lung after cryosurgery and found that NF-kappa B activation was strikingly increased in the liver but not the lung at 30 minutes and in both organs 1 hour after cryosurgery, and returned to baseline in both organs by 2 hours. In rats undergoing 35% hepatectomy, no increase in NF-kappa B activation was detected in nuclear extracts of either liver or lung at any time point. CONCLUSIONS: These data show that hepatic cryosurgery results in systemic inflammation with activation of NF-kappa B and increased production of NF-kappa B-dependent cytokines. Our data suggest that lung injury and death in this animal model is mediated by an exaggerated inflammatory response to cryosurgery.

Hepatic cryoablation-induced acute lung injury: pulmonary hemodynamic and permeability effects in a sheep model.

HYPOTHESIS: Hepatic cryoablation of 30% to 35% or more of liver parenchyma in a sheep model results in eicosanoid and nuclear factor-kappaB (NF-kappaB)-mediated changes in pulmonary hemodynamics and lung permeability. SETTING: Laboratory. INTERVENTIONS: At initial thoracotomy, catheters were placed in the main pulmonary artery, left atrium, right carotid artery, and efferent duct of the caudal mediastinal lymph node for subsequent monitoring in adult sheep. After a 1- to 2-week period of recovery, animals underwent laparotomy and left-lobe cryoablation (approximately 35% by volume) with subsequent awake monitoring and on postoperative days 1 to 3. MAIN OUTCOME MEASURES: Cryoablation-induced lung permeability and hemodynamic changes were compared with baseline values in sheep that underwent instrumentation. Similarly handled sheep underwent resection of a similar volume of hepatic parenchyma or had pulmonary artery pressure increases induced by mechanical left atrial obstruction. Activation of NF-kappaB was assessed with electrophoretic mobility shift assay, and serum thromboxane levels were measured with mass spectroscopy. RESULTS: Cryoablation resulted in acutely increased mean pulmonary (20 to 35 cm water) and systemic pressures, which returned to baseline at 24 hours with no change in cardiac output. Serum thromboxane levels increased 30 minutes after cryoablation (9-fold) and returned to baseline at 24 hours. Activation of NF-kappaB was present in liver and lung tissue by 30 minutes after cryoablation. Lung lymph-plasma protein clearance markedly exceeded the expected increase from pulmonary pressures alone, and increased lymph-plasma protein ratio persisted after pulmonary artery pressures normalized. Similar changes were not associated with 35% hepatic resection. CONCLUSIONS: This study demonstrates that 35% hepatic cryoablation results in an acute but transient increase in pulmonary artery pressure that may be mediated by increased thromboxane levels. Increases in pulmonary capillary permeability are not accounted for by pressure changes alone, and may be a result of NF-kappaB-mediated inflammatory mechanisms. These data show that cryosurgery causes pathophysiological changes similar to those observed with endotoxin and other systemic inflammatory stimuli.

Mass data massage: an automated data processing system used for NHEXAS, Arizona. National Human Exposure Assessment Survey.

Data entry and management are critical components of all large survey projects; data quality objectives must be met and data must be quickly and readily accessible. We developed a comprehensive system for data entry and management utilizing scannable forms with bubble fields and handwriting recognition. This 'Mass Data Massage' (MDM) system had three components: (1) form creation and database definition; (2) programming of data dictionaries for documentation and preliminary logic and range checks; and (3) data entry, management and documentation using the 'Mass Data Cleaning Program' (MDCP). Scannable forms were written in Teleform, where the data field definition, variable names and ranges were defined as the form was created. Completed forms were returned from the field, subjected to final field quality control (QC) checks, and transferred to the data management section. They were batched and coded as necessary. Once a batch of data was scanned and visually verified, the operator called up the menu for the MDCP. The MDCP had 31 program modules with 500-1200 lines of code each. The operator could select and run the appropriate dictionary on each data batch 'correcting' apparent errors in responses. This process was iterative until the data batch passed all dictionary checks. Proposed 'changes' were forwarded to the data coordinator (DC) for acceptance or rejection. After all errors had been resolved, each data batch was subjected to a 10% quality assurance (QA) check. The original data batch and associated file of applied changes were archived. Time expenditure using the scanning approach varied with the number of questions and the types of responses (handwritten or bubble fields). One-page forms took 42-60% of the time needed for hand entry; forms longer than 10 pages took 35-38% of the time. Use of faster machines will further speed the process. The main advantage of the system was the reduction of systematic errors. Scanning alone reduced errors found on 995 NHEXAS Baseline Questionnaires. Overall, the dictionary identified 0.55% errors on the scanned forms. Ten percent QC checks, performed on corrected batches ready for appendage to the master database, revealed an overall error rate of 0.02%. Similar checks on a laboratory form scanned from numeric handwriting detected 0.3% errors following dictionary application and 0.2% errors during the 10% QA check. This system was faster, more accurate, and more cost-effective than hand entry of data. A batch of data that took >1 week to process using the hand entry method was processed within 1 day using MDM. Human coding of specific answers and the final verification were the most time-consuming processes.

Suppression of lung inflammation in rats by prevention of NF-kappaB activation in the liver.

Activation of NF-kappaB and production of NF-kappaB-dependent chemokines are thought to be involved in the pathogenesis of neutrophilic lung inflammation. Calpain-1 inhibitor (CI-1) blocks activation of NF-kappaB by preventing proteolysis of the inhibitory protein IkappaB-alpha by the ubiquitin/proteasome pathway. We hypothesized that inhibition of proteasome function with CI-1 would block NF-kappaB activation in vivo after intraperitoneal (i.p.) treatment with bacterial lipopolysaccharide (LPS), and that NF-kappaB inhibition would be associated with suppression of chemokine gene expression and attenuation of neutrophilic alveolitis. We treated rats with a single i.p. injection of CI-1 (10 mg/kg) two hours prior to i.p. LPS (7 mg/kg). Treatment with Cl-1 prevented degradation of IkappaB-alpha and activation of NF-kappaB in the liver in response to LPS; however, Cl-1 treatment had no detected effect on NF-kappaB activation in lung tissue. CI-1 treatment prior to LPS resulted in 40% lower MIP-2 concentration in lung lavage fluid compared to rats treated with vehicle prior to LPS (502 +/- 112 pg/ml vs. 859 +/-144 pg/ml, P < 0.05). In addition, CI-1 treatment substantially inhibited LPS-induced neutrophilic alveolitis (2.7+ /- 1.2 x 10(5) vs. 43.7 +/- 12.2 x 10(5) lung lavage neutrophils, P < 0.01). These data indicate that NF-kappaB inhibition in the liver can alter lung inflammation induced by systemic LPS treatment and suggest that a liver-lung interaction contributes to the inflammatory response of the lung.

Dysregulated cytokine production in human cystic fibrosis bronchial epithelial cells.

Although pulmonary inflammation is an important pathologic event in cystic fibrosis (CF), the relationship between expression of the CF gene and the inflammatory response is unclear. We studied tumor necrosis factor (TNF) alpha and IL-1beta stimulated production of IL-6 and IL-8 by CF, corrected CF, and normal human bronchial epithelial cells in culture. During the first 24 hours of TNFalpha stimulation, CF cells produced significantly more IL-8 than normal or corrected CF cells. In the second 24 hours of TNFalpha stimulation, IL-6 and IL-8 generation ceased in normal and corrected CF cells but accelerated in CF cells, resulting in marked IL-6 and IL-8 accumulation in CF cells. Similar results were found when cells were stimulated with IL-1beta. Finally, when CF cells were grown at 27 degrees C (a culture condition which results in transport of CF transmembrane conductance regulator, CFTR, to the cell membrane and normalization of chloride conductance) TNFalpha-stimulated production of IL-6 and IL-8 reverted to normal. We conclude that dysregulation of cytokine generation by CF bronchial epithelial cells is directly related to expression of mutant CFTR and these observations provide a potential mechanism for persistence of airway inflammation in CF.

Epithelial nuclear factor-κB signaling promotes lung carcinogenesis via recruitment of regulatory T lymphocytes.

The mechanisms by which chronic inflammatory lung diseases, particularly chronic obstructive pulmonary disease, confer enhanced risk for lung cancer are not well-defined. To investigate whether nuclear factor (NF)-κB, a key mediator of immune and inflammatory responses, provides an interface between persistent lung inflammation and carcinogenesis, we utilized tetracycline-inducible transgenic mice expressing constitutively active IκB kinase ß in airway epithelium (IKTA (IKKß trans-activated) mice). Intraperitoneal injection of ethyl carbamate (urethane), or 3-methylcholanthrene (MCA) and butylated hydroxytoluene (BHT) was used to induce lung tumorigenesis. Doxycycline-treated IKTA mice developed chronic airway inflammation and markedly increased numbers of lung tumors in response to urethane, even when transgene expression (and therefore epithelial NF-κB activation) was begun after exposure to carcinogen. Studies using a separate tumor initiator/promoter model (MCA+BHT) indicated that NF-κB functions as an independent tumor promoter. Enhanced tumor formation in IKTA mice was preceded by increased proliferation and reduced apoptosis of alveolar epithelium, resulting in increased formation of premalignant lesions. Investigation of inflammatory cells in lungs of IKTA mice revealed a substantial increase in macrophages and lymphocytes, including functional CD4+/CD25+/FoxP3+ regulatory T lymphocytes (Tregs). Importantly, Treg depletion using repetitive injections of anti-CD25 antibodies limited excessive tumor formation in IKTA mice. At 6 weeks following urethane injection, antibody-mediated Treg depletion in IKTA mice reduced the number of premalignant lesions in the lungs in association with an increase in CD8 lymphocytes. Thus, persistent NF-κB signaling in airway epithelium facilitates carcinogenesis by sculpting the immune/inflammatory environment in the lungs.

Inhibition of NF-kappa B activity in mammary epithelium increases tumor latency and decreases tumor burden.

The transcription factor nuclear factor kappa B (NF-κB) is activated in human breast cancer tissues and cell lines. However, it is unclear whether NF-κB activation is a consequence of tumor formation or a contributor to tumor development. We developed a doxycycline (dox)-inducible mouse model, termed DNMP, to inhibit NF-κB activity specifically within the mammary epithelium during tumor development in the polyoma middle T oncogene (PyVT) mouse mammary tumor model. DNMP females and PyVT littermate controls were treated with dox from 4 to 12 weeks of age. We observed an increase in tumor latency and a decrease in final tumor burden in DNMP mice compared with PyVT controls. A similar effect with treatment from 8 to 12 weeks indicates that outcome is independent of effects on postnatal virgin ductal development. In both cases, DNMP mice were less likely to develop lung metastases than controls. Treatment from 8 to 9 weeks was sufficient to impact primary tumor formation. Inhibition of NF-κB increases apoptosis in hyperplastic stages of tumor development and decreases proliferation at least in part by reducing Cyclin D1 expression. To test the therapeutic potential of NF-κB inhibition, we generated palpable tumors by orthotopic injection of PyVT cells and then treated systemically with the NF-κB inhibitor thymoquinone (TQ). TQ treatment resulted in a reduction in tumor volume and weight as compared with vehicle-treated control. These data indicate that epithelial NF-κB is an active contributor to tumor progression and demonstrate that inhibition of NF-κB could have a significant therapeutic impact even at later stages of mammary tumor progression.

Gold pulmonary toxicity in a patient with a normal chest radiograph.

We report a case of gold pulmonary toxicity in a patient with adult-onset Still's disease with dyspnea on exertion and a normal chest radiograph. Withdrawal of gold therapy resulted in complete resolution of pulmonary toxicity in our patient without the need for additional steroid therapy.