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International Journal of Molecular... Feb 2018Asbestos is a known carcinogen and exposure can lead to lung cancer and malignant mesothelioma. To examine the effects of asbestos fibers on human immune cells, the... (Review)
Review
Asbestos is a known carcinogen and exposure can lead to lung cancer and malignant mesothelioma. To examine the effects of asbestos fibers on human immune cells, the human T cell leukemia/lymphoma virus (HTLV)-1 immortalized human T cell line MT-2 was employed. Following continuous exposure to asbestos fibers for more than eight months, MT-2 sublines showed acquisition of resistance to asbestos-induced apoptosis with decreased death signals and increased surviving signals. These sublines showed various characteristics that suggested a reduction in anti-tumor immunity. On the other hand, inflammatory changes such as expression of MMP7, CXCR5, CXCL13 and CD44 was found to be markedly higher in sublines continuously exposed to asbestos compared with original MT-2 cells. All of these molecules contribute to lung inflammation, T and B cell interactions and connections between mesothelial cells and T cells. Thus, further investigation focusing on these molecules may shed light on the role of chronic inflammation caused by asbestos exposure and the occurrence of malignant mesothelioma. Finally, regarding peripheral T cells from healthy donors (HD) and asbestos-exposed patients with pleural plaque (PP) or malignant pleural mesothelioma (MPM), following stimulation of CD4+ T cells, T cells from MPM patients showed reduced potential of interferon (IFN)-γ expression. Moreover, levels of interleukin (IL)-6, one of the most important cytokines in chronic inflammation, in cultured supernatants were higher in PP and MPM patients compared with HD. Overall, asbestos-induced chronic inflammation in the lung as well as the pleural cavity may facilitate the onset of asbestos-induced cancers due to alterations in the interactions among fibers, immune cells such as T and B cells and macrophages, and mesothelial and lung epithelial cells. Further investigations regarding chronic inflammation caused by asbestos fibers may assist in identifying molecular targets for preventive and therapeutic strategies related to the effects of asbestos exposure.
Topics: Animals; Apoptosis; Asbestos; Biomarkers; Carcinogens; Cytokines; Environmental Exposure; Humans; Inflammation; Inflammation Mediators; Lung Neoplasms; Mesothelioma; Mesothelioma, Malignant; T-Lymphocytes
PubMed: 29419731
DOI: 10.3390/ijms19020504 -
Translational Research : the Journal of... Apr 2009Asbestos causes asbestosis (pulmonary fibrosis caused by asbestos inhalation) and malignancies (bronchogenic carcinoma and mesothelioma) by mechanisms that are not fully... (Review)
Review
Asbestos causes asbestosis (pulmonary fibrosis caused by asbestos inhalation) and malignancies (bronchogenic carcinoma and mesothelioma) by mechanisms that are not fully elucidated. Despite a dramatic reduction in asbestos use worldwide, asbestos-induced lung diseases remain a substantial health concern primarily because of the vast amounts of fibers that have been mined, processed, and used during the 20th century combined with the long latency period of up to 40 years between exposure and disease presentation. This review summarizes the important new epidemiologic and pathogenic information that has emerged over the past several years. Whereas the development of asbestosis is directly associated with the magnitude and duration of asbestos exposure, the development of a malignant clone of cells can occur in the setting of low-level asbestos exposure. Emphasis is placed on the recent epidemiologic investigations that explore the malignancy risk that occurs from nonoccupational, environmental asbestos exposure. Accumulating studies are shedding light on novel mechanistic pathways by which asbestos damages the lung. Attention is focused on the importance of alveolar epithelial cell (AEC) injury and repair, the role of iron-derived reactive oxygen species (ROS), and apoptosis by the p53- and mitochondria-regulated death pathways. Furthermore, recent evidence underscores crucial roles for specific cellular signaling pathways that regulate the production of cytokines and growth factors. An evolving role for epithelial-mesenchymal transition (EMT) is also reviewed. The translational significance of these studies is evident in providing the molecular basis for developing novel therapeutic strategies for asbestos-related lung diseases and, importantly, other pulmonary diseases, such as interstitial pulmonary fibrosis and lung cancer.
Topics: Asbestos; Humans; Lung Diseases
PubMed: 19304273
DOI: 10.1016/j.trsl.2009.01.004 -
Report on Carcinogens : Carcinogen... 2011
Topics: Animals; Asbestos; Carcinogens; Humans; Neoplasms
PubMed: 21836646
DOI: No ID Found -
La Medicina Del Lavoro Dec 2023Quantification of asbestos fibers has been mainly performed in the lung but rarely in other organs. However, this may be relevant to understanding better translocation... (Review)
Review
BACKGROUND
Quantification of asbestos fibers has been mainly performed in the lung but rarely in other organs. However, this may be relevant to understanding better translocation pathways and the oncogenic effects of asbestos on the human body. Electron microscopy is the best technology available to assess the type of fiber, dimensions, and distribution of asbestos fibers in different tissues and as a biomarker of cumulative dose.
OBJECTIVES
This scoping review aims to summarize the findings of the studies in which asbestos fibers have been quantified by electron microscopy, occasionally associated with X-ray microanalysis, in normal and pathological tissue of ten abdominal organs.
METHODS
A scoping review has been performed by searching articles that quantified asbestos fibers in abdominal organs by electron microscopy (Scanning- SEM or Transmission- TEM).
RESULTS
The 12 selected studies included 204 cases, and 325 samples were analyzed. The colon and rectum, kidney, bladder, and abdominal lymph nodes were the organs with at least ten samples available with quantification of asbestos fibers. Asbestos fibers were detected in all the abdominal organs considered: the highest value (152,32 million fibers per gram of dry tissue) was found in the colon and was identified using STEM with EDS.
CONCLUSION
The studies included were heterogeneous in terms of exposure and cases, type of samples, as well as analytical techniques, therefore we cannot confirm a specific pattern of distribution in any organ, based on the low homogeneity of the exposure status. The colon is the organ in which the number of fibers is the highest, probably because of exposure arising from both internal distribution of inhaled fibers and ingestion. Additional studies of the number of asbestos fibers in abdominal organs should be made to achieve better representativity.
Topics: Humans; Asbestos; Lung
PubMed: 38060208
DOI: 10.23749/mdl.v114i6.14946 -
International Journal of Environmental... Jan 2022Due to the long lag-time for health outcomes, historical asbestos exposure measurements are valuable to support assessments of associated occupational health effects,...
OBJECTIVES
Due to the long lag-time for health outcomes, historical asbestos exposure measurements are valuable to support assessments of associated occupational health effects, and also to assess time trends and effects of preventive measures.
METHODS
Different sources of stored data were collated, assessed and refined to create a harmonized database on historical asbestos fibre concentrations measured in specific work tasks and different industries. The final database contains 9236 asbestos measurements from Danish workplaces collected from 1971 to 1997.
RESULTS
The geometric mean of asbestos concentrations in different occupations and tasks ranged from 0.003 to 35 fibres cm. Highest concentrations were registered during handling of asbestos products in the construction services during the period 1981-1997. Although all the measured asbestos exposures without the use of respiratory equipment by the worker in the period of 1971-1997 exceeded the current 8-h time-weighted average exposure limit of 0.1 fibres cm, the majority of samples collected in the earlier period of 1971 to 1980 did not exceed the exposure limit of 2 fibres cm, which was in place at the time. All exposure data obtained from 1980 and onwards were found to be one seventh of the mean fibre concentrations in the previous measurement period. The impact of time shows a clear exponentially decreasing trend-line.
CONCLUSIONS
Despite limitations in coverage of different occupations and tasks associated with the inventoried historical asbestos measurements, the data are helpful to identify specific work scenarios within an industry, where relatively high asbestos exposure levels may still occur or have occurred from 1971 to 1997.
Topics: Air Pollutants, Occupational; Asbestos; Denmark; Occupational Exposure; Occupational Health; Occupations
PubMed: 35055465
DOI: 10.3390/ijerph19020643 -
International Journal of Environmental... Jul 2018Although workplace asbestos concentrations (AC) have been reported several times, the past environmental AC are relatively poorly studied. Due to the harmful effects of...
Although workplace asbestos concentrations (AC) have been reported several times, the past environmental AC are relatively poorly studied. Due to the harmful effects of the asbestos industry, production has moved from early industrialized countries (Japan), to late industrialized countries (Korea), and finally to industrializing countries (Indonesia). The purpose of this study was to determine current occupational exposure levels and evaluate neighborhood environmental exposure levels in an Indonesian asbestos textile factory through collaboration among three generation of industrialized countries. Asbestos concentrations were measured inside and outside of the factory and compared with simulated data. ACs in the factory were similar to those of 1980s and 1990s levels in the Korean factory that transferred the machines. Environmental ACs were dispersed according to wind direction. There were no significant differences between monitored and simulated data, and correlation coefficients between downwind, upwind, and middle wind directions were high, with some statistical significance. This study can be used to estimate past environmental ACs to understand the causality of asbestos related diseases. Because of the small sample size and specific weather conditions, a large-scale study of various asbestos exposure sources, including asbestos cement factories, shipyards, and mines, and various atmospheric conditions is required.
Topics: Asbestos; Environmental Exposure; Environmental Monitoring; Humans; Indonesia; Occupational Exposure; Textiles; Wind; Workplace
PubMed: 29970825
DOI: 10.3390/ijerph15071398 -
American Journal of Industrial Medicine Mar 2022Vermiculite ore from Libby, Montana contains on average 24% of a mixture of toxic and carcinogenic amphibole asbestiform fibers. These comprise primarily winchite (84%),...
BACKGROUND
Vermiculite ore from Libby, Montana contains on average 24% of a mixture of toxic and carcinogenic amphibole asbestiform fibers. These comprise primarily winchite (84%), with smaller quantities of richterite (11%) and tremolite (6%), which are together referred to as Libby amphibole (LA).
METHODS
A total of 1883 individuals who were occupationally and/or environmentally exposed to LA and were diagnosed with asbestos-related pleuropulmonary disease (ARPPD) following participation in communitywide screening programs supported by the Agency for Toxic Substances and Disease Registry (ATSDR) and followed up at the Center for Asbestos Related Disease (CARD) between 2000 and 2010. There were 203 deaths of patients with sufficient records and radiographs. Best clinical and radiologic evidence was used to determine the cause of death, which was compared with death certificates.
RESULTS
Asbestos-related mortality was 55% (n = 112) in this series of 203 patients. Of the 203 deaths, 34 (17%) were from asbestos-related malignancy, 75 (37%) were from parenchymal asbestosis, often with pleural fibrosis, and 3 (1.5%) were from respiratory failure secondary to pleural thickening.
CONCLUSIONS
Asbestos is the leading cause of mortality following both occupational and nonoccupational exposure to LA in those with asbestos-related disease.
Topics: Asbestos; Asbestos, Amphibole; Asbestosis; Humans; Montana; Pleural Diseases
PubMed: 34961951
DOI: 10.1002/ajim.23320 -
Environmental Health : a Global Access... Jul 2014The fibrogenicity and carcinogenicity of asbestos fibers are dependent on several fiber parameters including fiber dimensions. Based on the WHO (World Health... (Review)
Review
The fibrogenicity and carcinogenicity of asbestos fibers are dependent on several fiber parameters including fiber dimensions. Based on the WHO (World Health Organization) definition, the current regulations focalise on long asbestos fibers (LAF) (Length: L ≥ 5 μm, Diameter: D < 3 μm and L/D ratio > 3). However air samples contain short asbestos fibers (SAF) (L < 5 μm). In a recent study we found that several air samples collected in buildings with asbestos containing materials (ACM) were composed only of SAF, sometimes in a concentration of ≥10 fibers.L-1. This exhaustive review focuses on available information from peer-review publications on the size-dependent pathogenetic effects of asbestos fibers reported in experimental in vivo and in vitro studies. In the literature, the findings that SAF are less pathogenic than LAF are based on experiments where a cut-off of 5 μm was generally made to differentiate short from long asbestos fibers. Nevertheless, the value of 5 μm as the limit for length is not based on scientific evidence, but is a limit for comparative analyses. From this review, it is clear that the pathogenicity of SAF cannot be completely ruled out, especially in high exposure situations. Therefore, the presence of SAF in air samples appears as an indicator of the degradation of ACM and inclusion of their systematic search should be considered in the regulation. Measurement of these fibers in air samples will then make it possible to identify pollution and anticipate health risk.
Topics: Air Pollutants; Animals; Asbestos; Environmental Exposure; Humans; Inhalation Exposure; Occupational Exposure; Particle Size
PubMed: 25043725
DOI: 10.1186/1476-069X-13-59 -
Analytical Chemistry Feb 2022This is the first report of the use of laser ablation-inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-TOFMS) to analyze human malignant pleural...
This is the first report of the use of laser ablation-inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-TOFMS) to analyze human malignant pleural mesothelioma (MPM) samples at the cellular level. MPM is an aggressive, incurable cancer associated with asbestos exposure, with a long latency and poor overall survival. Following careful optimization of the laser fluence, the simultaneous ablation of soft biological tissue and hard mineral fibers was possible, allowing the spatial detection of elements such as Si, Mg, Ca, and Fe, which are also present in the glass substrate. A low-dispersion LA setup was employed, which provided the high spatial resolution necessary to identify the asbestos fibers and fiber fragments in the tissue and to characterize the metallome at the cellular level (a pixel size of 2 μm), with a high speed (at 250 Hz). The multielement LA-ICP-TOFMS imaging approach enabled (i) the detection of asbestos fibers/mineral impurities within the MPM tissue samples of patients, (ii) the visualization of the tissue structure with the endogenous elemental pattern at high spatial resolution, and (iii) obtaining insights into the metallome of MPM patients with different pathologies in a single analysis run. Asbestos and other mineral fibers were detected in the lung and pleura tissue of MPM patients, respectively, based on their multielement pattern (Si, Mg, Ca, Fe, and Sr). Interestingly, strontium was detected in asbestos fibers, suggesting a link between this potential toxic element and MPM pathogenesis. Furthermore, monitoring the metallome around the talc deposit regions (characterized by elevated levels of Al, Mg, and Si) revealed significant tissue damage and inflammation caused by talc pleurodesis. LA-ICP-TOFMS results correlated to Perls' Prussian blue and histological staining of the corresponding serial sections. Ultimately, the ultra-high-speed and high-spatial-resolution capabilities of this novel LA-ICP-TOFMS setup may become an important clinical tool for simultaneous asbestos detection, metallome monitoring, and biomarker identification.
Topics: Asbestos; Humans; Laser Therapy; Mass Spectrometry; Mesothelioma, Malignant; Spectrum Analysis
PubMed: 35073065
DOI: 10.1021/acs.analchem.1c04857 -
Cancer Science Aug 2012The emergence of nanotechnology represents an important milestone, as it opens the way to a broad spectrum of applications for nanomaterials in the fields of... (Review)
Review
The emergence of nanotechnology represents an important milestone, as it opens the way to a broad spectrum of applications for nanomaterials in the fields of engineering, industry and medicine. One example of nanomaterials that have the potential for widespread use is carbon nanotubes, which have a tubular structure made of graphene sheets. However, there have been concerns that they may pose a potential health risk due to their similarities to asbestos, namely their high biopersistence and needle-like structure. We recently found that despite these similarities, carbon nanotubes and asbestos differ in certain aspects, such as their mechanism of entry into mesothelial cells. In the study, we showed that non-functionalized, multi-walled carbon nanotubes enter mesothelial cells by directly piercing through the cell membrane in a diameter- and rigidity-dependent manner, whereas asbestos mainly enters these cells through the process of endocytosis, which is independent of fiber diameter. In this review, we discuss the key differences, as well as similarities, between asbestos fibers and carbon nanotubes. We also summarize previous reports regarding the mechanism of carbon nanotube entry into non-phagocytic cells. As the entry of fibers into mesothelial cells is a crucial step in mesothelial carcinogenesis, we believe that a comprehensive study on the differences by which carbon nanotubes and asbestos fibers enter into non-phagocytic cells will provide important clues for the safer manufacture of carbon nanotubes through strict regulation on fiber characteristics, such as diameter, surface properties, length and rigidity.
Topics: Asbestos; Carcinogens, Environmental; Cell Transformation, Neoplastic; Epithelial Cells; Humans; Nanostructures; Nanotechnology; Nanotubes, Carbon; Neoplasms, Mesothelial
PubMed: 22568550
DOI: 10.1111/j.1349-7006.2012.02326.x