The presence of emphysema is relatively common in patients with fibrotic interstitial lung disease. This has been designated combined pulmonary fibrosis and emphysema (CPFE). The lack of consensus ...over definitions and diagnostic criteria has limited CPFE research.
The objectives of this task force were to review the terminology, definition, characteristics, pathophysiology, and research priorities of CPFE and to explore whether CPFE is a syndrome.
This research statement was developed by a committee including 19 pulmonologists, 5 radiologists, 3 pathologists, 2 methodologists, and 2 patient representatives. The final document was supported by a focused systematic review that identified and summarized all recent publications related to CPFE.
This task force identified that patients with CPFE are predominantly male, with a history of smoking, severe dyspnea, relatively preserved airflow rates and lung volumes on spirometry, severely impaired Dl
, exertional hypoxemia, frequent pulmonary hypertension, and a dismal prognosis. The committee proposes to identify CPFE as a syndrome, given the clustering of pulmonary fibrosis and emphysema, shared pathogenetic pathways, unique considerations related to disease progression, increased risk of complications (pulmonary hypertension, lung cancer, and/or mortality), and implications for clinical trial design. There are varying features of interstitial lung disease and emphysema in CPFE. The committee offers a research definition and classification criteria and proposes that studies on CPFE include a comprehensive description of radiologic and, when available, pathological patterns, including some recently described patterns such as smoking-related interstitial fibrosis.
This statement delineates the syndrome of CPFE and highlights research priorities.
Engineered carbon nanotubes are currently used in many consumer and industrial products such as paints, sunscreens, cosmetics, toiletries, electronic processes and industrial lubricants. Carbon ...nanotubes are among the more widely used nanoparticles and come in two major commercial forms, single-walled carbon nanotubes (SWCNT) and the more rigid, multi-walled carbon nanotubes (MWCNT). The low density and small size of these particles makes respiratory exposures likely. Many of the potential health hazards have not been investigated, including their potential for carcinogenicity. We, therefore, utilized a two stage initiation/promotion protocol to determine whether inhaled MWCNT act as a complete carcinogen and/or promote the growth of cells with existing DNA damage. Six week old, male, B6C3F1 mice received a single intraperitoneal (ip) injection of either the initiator methylcholanthrene(MCA, 10 μg/g BW, i.p.), or vehicle (corn oil). One week after i.p. injections, mice were exposed by inhalation to MWCNT (5 mg/m³, 5 hours/day, 5 days/week) or filtered air (controls) for a total of 15 days. At 17 months post-exposure, mice were euthanized and examined for lung tumor formation.
Twenty-three percent of the filtered air controls, 26.5% of the MWCNT-exposed, and 51.9% of the MCA-exposed mice, had lung bronchiolo-alveolar adenomas and lung adenocarcinomas. The average number of tumors per mouse was 0.25, 0.81 and 0.38 respectively. By contrast, 90.5% of the mice which received MCA followed by MWCNT had bronchiolo-alveolar adenomas and adenocarcinomas with an average of 2.9 tumors per mouse 17 months after exposure. Indeed, 62% of the mice exposed to MCA followed by MWCNT had bronchiolo-alveolar adenocarcinomas compared to 13% of the mice that received filtered air, 22% of the MCA-exposed, or 14% of the MWCNT-exposed. Mice with early morbidity resulting in euthanasia had the highest rate of metastatic disease. Three mice exposed to both MCA and MWCNT that were euthanized early had lung adenocarcinoma with evidence of metastasis (5.5%). Five mice (9%) exposed to MCA and MWCNT and 1 (1.6%) exposed to MCA developed serosal tumors morphologically consistent with sarcomatous mesotheliomas, whereas mice administered MWCNT or air alone did not develop similar neoplasms.
These data demonstrate that some MWCNT exposures promote the growth and neoplastic progression of initiated lung cells in B6C3F1 mice. In this study, the mouse MWCNT lung burden of 31.2 μg/mouse approximates feasible human occupational exposures. Therefore, the results of this study indicate that caution should be used to limit human exposures to MWCNT.
This guideline addresses the diagnosis of hypersensitivity pneumonitis (HP). It represents a collaborative effort among the American Thoracic Society, Japanese Respiratory Society, and Asociación ...Latinoamericana del Tórax.
Systematic reviews were performed for six questions. The evidence was discussed, and then recommendations were formulated by a multidisciplinary committee of experts in the field of interstitial lung disease and HP using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach.
The guideline committee defined HP, and clinical, radiographic, and pathological features were described. HP was classified into nonfibrotic and fibrotic phenotypes. There was limited evidence that was directly applicable to all questions. The need for a thorough history and a validated questionnaire to identify potential exposures was agreed on. Serum IgG testing against potential antigens associated with HP was suggested to identify potential exposures. For patients with nonfibrotic HP, a recommendation was made in favor of obtaining bronchoalveolar lavage (BAL) fluid for lymphocyte cellular analysis, and suggestions for transbronchial lung biopsy and surgical lung biopsy were also made. For patients with fibrotic HP, suggestions were made in favor of obtaining BAL for lymphocyte cellular analysis, transbronchial lung cryobiopsy, and surgical lung biopsy. Diagnostic criteria were established, and a diagnostic algorithm was created by expert consensus. Knowledge gaps were identified as future research directions.
The guideline committee developed a systematic approach to the diagnosis of HP. The approach should be reevaluated as new evidence accumulates.
Hypersensitivity pneumonitis (HP) is an interstitial lung disease with a better prognosis, on average, than idiopathic pulmonary fibrosis (IPF). We compare survival time and pulmonary function ...trajectory in patients with HP and IPF by radiologic phenotype.
HP (n = 117) was diagnosed if surgical/transbronchial lung biopsy, BAL, and exposure history results suggested this diagnosis. IPF (n = 152) was clinically and histopathologically diagnosed. All participants had a baseline high-resolution CT (HRCT) scan and FVC % predicted. Three thoracic radiologists documented radiologic features. Survival time is from HRCT scan to death or lung transplant. Cox proportional hazards models identify variables associated with survival time. Linear mixed models compare post-HRCT scan FVC % predicted trajectories.
Subjects were grouped by clinical diagnosis and three mutually exclusive radiologic phenotypes: honeycomb present, non-honeycomb fibrosis (traction bronchiectasis and reticulation) present, and nonfibrotic. Nonfibrotic HP had the longest event-free median survival (> 14.73 years) and improving FVC % predicted (1.92%; 95% CI, 0.49-3.35; P = .009). HP with non-honeycomb fibrosis had longer survival than IPF (> 7.95 vs 5.20 years), and both groups experienced a significant decline in FVC % predicted. Subjects with HP and IPF with honeycombing had poor survival (2.76 and 2.81 years, respectively) and significant decline in FVC % predicted.
Three prognostically distinct, radiologically defined phenotypes are identified among patients with HP. The importance of pursuing a specific diagnosis (eg, HP vs IPF) among patients with non-honeycomb fibrosis is highlighted. When radiologic honeycombing is present, invasive diagnostic testing directed at determining the diagnosis may be of limited value given a uniformly poor prognosis.
Transmission electron microscopy (TEM) is widely used as an imaging modality to provide high-resolution details of subcellular components within cells and tissues. Mitochondria and endoplasmic ...reticulum (ER) are organelles of particular interest to those investigating metabolic disorders. A straightforward method for quantifying and characterizing particular aspects of these organelles would be a useful tool. In this protocol, we outline how to accurately assess the morphology of these important subcellular structures using open source software
, originally developed by the National Institutes of Health (NIH). Specifically, we detail how to obtain mitochondrial length, width, area, and circularity, in addition to assessing cristae morphology and measuring mito/endoplasmic reticulum (ER) interactions. These procedures provide useful tools for quantifying and characterizing key features of sub-cellular morphology, leading to accurate and reproducible measurements and visualizations of mitochondria and ER.
Carbon nanotubes are commercially-important products of nanotechnology; however, their low density and small size makes carbon nanotube respiratory exposures likely during their production or ...processing. We have previously shown mitotic spindle aberrations in cultured primary and immortalized human airway epithelial cells exposed to single-walled carbon nanotubes (SWCNT). In this study, we examined whether multi-walled carbon nanotubes (MWCNT) cause mitotic spindle damage in cultured cells at doses equivalent to 34 years of exposure at the NIOSH Recommended Exposure Limit (REL). MWCNT induced a dose responsive increase in disrupted centrosomes, abnormal mitotic spindles and aneuploid chromosome number 24 hours after exposure to 0.024, 0.24, 2.4 and 24 μg/cm² MWCNT. Monopolar mitotic spindles comprised 95% of disrupted mitoses. Three-dimensional reconstructions of 0.1 μm optical sections showed carbon nanotubes integrated with microtubules, DNA and within the centrosome structure. Cell cycle analysis demonstrated a greater number of cells in S-phase and fewer cells in the G2 phase in MWCNT-treated compared to diluent control, indicating a G1/S block in the cell cycle. The monopolar phenotype of the disrupted mitotic spindles and the G1/S block in the cell cycle is in sharp contrast to the multi-polar spindle and G2 block in the cell cycle previously observed following exposure to SWCNT. One month following exposure to MWCNT there was a dramatic increase in both size and number of colonies compared to diluent control cultures, indicating a potential to pass the genetic damage to daughter cells. Our results demonstrate significant disruption of the mitotic spindle by MWCNT at occupationally relevant exposure levels.
Muscle weakness and myopathy are observed in vitamin D deficiency and chronic renal failure, where concentrations of the active vitamin D3 metabolite, 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3), are ...low. To evaluate the mechanism of action of 1α,25(OH)2D3 in skeletal muscle, we examined mitochondrial oxygen consumption, dynamics, and biogenesis and changes in expression of nuclear genes encoding mitochondrial proteins in human skeletal muscle cells following treatment with 1α,25(OH)2D3. The mitochondrial oxygen consumption rate (OCR) increased in 1α,25(OH)2D3-treated cells. Vitamin D3 metabolites lacking a 1α-hydroxyl group (vitamin D3, 25-hydroxyvitamin D3, and 24R,25-dihydroxyvitamin D3) decreased or failed to increase OCR. 1α-Hydroxyvitamin D3 did not increase OCR. In 1α,25(OH)2D3-treated cells, mitochondrial volume and branching and expression of the pro-fusion protein OPA1 (optic atrophy 1) increased, whereas expression of the pro-fission proteins Fis1 (fission 1) and Drp1 (dynamin 1-like) decreased. Phosphorylated pyruvate dehydrogenase (PDH) (Ser-293) and PDH kinase 4 (PDK4) decreased in 1α,25(OH)2D3-treated cells. There was a trend to increased PDH activity in 1α,25(OH)2D3-treated cells (p = 0.09). 83 nuclear mRNAs encoding mitochondrial proteins were changed following 1α,25(OH)2D3 treatment; notably, PDK4 mRNA decreased, and PDP2 mRNA increased. MYC, MAPK13, and EPAS1 mRNAs, which encode proteins that regulate mitochondrial biogenesis, were increased following 1α,25(OH)2D3 treatment. Vitamin D receptor-dependent changes in the expression of 1947 mRNAs encoding proteins involved in muscle contraction, focal adhesion, integrin, JAK/STAT, MAPK, growth factor, and p53 signaling pathways were observed following 1α,25(OH)2D3 treatment. Five micro-RNAs were induced or repressed by 1α,25(OH)2D3. 1α,25(OH)2D3 regulates mitochondrial function, dynamics, and enzyme function, which are likely to influence muscle strength.
Development of distant metastases involves a complex multistep biological process termed the invasion-metastasis cascade, which includes dissemination of cancer cells from the primary tumor to ...secondary organs. NOTCH developmental signaling plays a critical role in promoting epithelial-to-mesenchymal transition, tumor stemness, and metastasis. Although all four NOTCH receptors show oncogenic properties, the unique role of each of these receptors in the sequential stepwise events that typify the invasion-metastasis cascade remains elusive.
We have established metastatic xenografts expressing high endogenous levels of NOTCH3 using estrogen receptor alpha-positive (ERα
) MCF-7 breast cancer cells with constitutive active Raf-1/mitogen-associated protein kinase (MAPK) signaling (vMCF-7
) and MDA-MB-231 triple-negative breast cancer (TNBC) cells. The critical role of NOTCH3 in inducing an invasive phenotype and poor outcome was corroborated in unique TNBC cells resulting from a patient-derived brain metastasis (TNBC-M25) and in publicly available claudin-low breast tumor specimens collected from participants in the Molecular Taxonomy of Breast Cancer International Consortium database.
In this study, we identified an association between NOTCH3 expression and development of metastases in ERα
and TNBC models. ERα
breast tumor xenografts with a constitutive active Raf-1/MAPK signaling developed spontaneous lung metastases through the clonal expansion of cancer cells expressing a NOTCH3 reprogramming network. Abrogation of NOTCH3 expression significantly reduced the self-renewal and invasive capacity of ex vivo breast cancer cells, restoring a luminal CD44
/CD24
/ERα
phenotype. Forced expression of the mitotic Aurora kinase A (AURKA), which promotes breast cancer metastases, failed to restore the invasive capacity of NOTCH3-null cells, demonstrating that NOTCH3 expression is required for an invasive phenotype. Likewise, pharmacologic inhibition of NOTCH signaling also impaired TNBC cell seeding and metastatic growth. Significantly, the role of aberrant NOTCH3 expression in promoting tumor self-renewal, invasiveness, and poor outcome was corroborated in unique TNBC cells from a patient-derived brain metastasis and in publicly available claudin-low breast tumor specimens.
These findings demonstrate the key role of NOTCH3 oncogenic signaling in the genesis of breast cancer metastasis and provide a compelling preclinical rationale for the design of novel therapeutic strategies that will selectively target NOTCH3 to halt metastatic seeding and to improve the clinical outcomes of patients with breast cancer.
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