Early effects of fluoro-edenite: correlation between IL-18 serum levels and pleural and parenchymal abnormalities

Asbestos exposure determined 357 days after death through autopsy: a report of a multidisciplinary approach

Asbestosis is an interstitial lung disease caused by the inhalation of asbestos fibers and poses a significant risk to individuals working in construction, shipping, mining, and related industries. In a forensic context, postmortem investigations are crucial for accurate diagnosis, for which the gold standard is the histopathological examination. This case report describes the autopsy and related investigations conducted on an 84-year-old man, nearly one year (357 days) after his death. After a post-mortem CT scan, an autoptic investigation was performed, followed by histopathological, immunohistochemical, and scanning electron microscopy examinations. The integration of the evidence from these examinations with previously available personal and clinical information conclusively confirmed the diagnosis of asbestosis. We demonstrated the efficacy and reliability of our diagnostic protocol in detecting asbestosis and asbestos fibers and excluding mesothelioma even in decomposed tissues. According to our findings autopsy remains the diagnostic gold standard in cases of suspected asbestosis within a forensic context, even 1 year after death, therefore it is always highly recommended, even in cases where the body has decomposed.

Influence of lead-induced toxicity on the inflammatory cytokines

Lead (Pb2+) is a hazardous heavy metal that is pervasive in the human environment as a result of anthropogenic activity, and poses serious health risks, particularly in children. Due to its innumerable unique physical and chemical properties, it has various applications; therefore, it has become a common environmental pollutant. Lead may cause oxidative stress, and accumulating evidence indicates that oxidative stress influences the pathophysiology of lead poisoning, also called plumbism. The immune system is continually exposed to various environmental pathogens and xenobiotics, including heavy metals such as lead, and appears to be one of the most vulnerable targets. After being exposed to lead, cells are subjected to oxidative stress as a result of reactive oxygen species (ROS) production. When the generation and consumption of ROS are out of equilibrium, various cell structures, particularly phospholipids are disrupted leading to lipid peroxidation. Various inflammatory signalling pathways are activated as a consequence, along with reduced disease resistance, inflammation, autoimmunity, sensitization and disruption of the cell-mediated and humoral immune systems. Lead negatively affects the metabolism of cytokines, including the interleukins IL-2, IL-1b, IL-6, IL-4, IL-8, tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN), as well as the expression and functioning of inflammatory enzymes such as cyclooxygenases. However, the cause of toxicity depends on the kind of lead, dosage, route of entry, exposure period, age, host and genetic predisposition.

Mesothelin methylation, soluble mesothelin related protein levels and inflammation profiling in workers chronically exposed to naturally occurring asbestos fibers

Exposure to asbestiform fibers, including chrysotile and amphibole, is carcinogenic, causing malignant pleural mesothelioma (MPM) when inhaled. Some populations globally face Naturally Occurring Asbestos (NOA) exposure, leading to MPM cases like in Biancavilla, Italy, from Fluoro-edenite (FE) contamination. Studies show NOA exposure causes epigenetic changes, focusing on mesothelin methylation, an MPM marker, and altered inflammation, emphasizing the health risks of FE and asbestos. This research, conducted from February 2022 to October 2022, studied 125 construction workers from Biancavilla and 125 controls from 40 km away without Biancavilla work history. With at least ten years in construction and no respiratory conditions, participants underwent medical assessments and gave blood samples for analysis, including inflammation markers, mesothelin methylation, and soluble mesothelin-related protein levels. The results showed similar demographics but differing inflammation and methylation levels in exposed workers, suggesting long-term cellular changes. Pearson correlation showed intricate biomarker relationships. Significant inflammatory differences were found between FE exposed and non-exposed workers, indicating potential health impacts from FE. This raises concerns for communities like Biancavilla, emphasizing the importance of extensive epigenetic research for public health.

Small RNA-Seq Transcriptome Profiling of Mesothelial and Mesothelioma Cell Lines Revealed microRNA Dysregulation after Exposure to Asbestos-like Fibers

Environmental exposure to fibers of respirable size has been identified as a risk for public health. Experimental evidence has revealed that a variety of fibers, including fluoro-edenite, can develop chronic respiratory diseases and elicit carcinogenic effects in humans. Fluoro-edenite (FE) is a silicate mineral first found in Biancavilla (Sicily, Italy) in 1997. Environmental exposure to its fibers has been correlated with a cluster of malignant pleural mesotheliomas. This neoplasm represents a public health problem due to its long latency and to its aggression not alerted by specific symptoms. Having several biomarkers providing us with data on the health state of those exposed to FE fibers or allowing an early diagnosis on malignant pleural mesothelioma, still asymptomatic patients, would be a remarkable goal. To these purposes, we reported the miRNA transcriptome in human normal mesothelial cell line (MeT-5A) and in the human malignant mesothelioma cell line (JU77) exposed and not exposed to FE fibers. The results showed a difference in the number of deregulated miRNAs between tumor and nontumor samples both exposed and not exposed to FE fibers. As a matter of fact, the effect of exposure to FE fibers is more evident in the expression of miRNA in the tumor samples than in the nontumor samples. In the present paper, several pathways involved in the pathogenesis of malignant pleural mesothelioma have been analyzed. We especially noticed the involvement of pathways that have important functions in inflammatory processes, angiogenesis, apoptosis, and necrosis. Besides this amount of data, further studies will be designed for the selection of the most significant miRNAs to test and validate their diagnostic potential, alone or in combination with other protein biomarkers, in high-risk individuals' liquid biopsy to have a noninvasive tool of diagnosis for this neoplasm.

New Trends in Immunohistochemical Methods to Estimate the Time since Death: A Review

The identification of a reliable and accurate post-mortem interval (PMI) is a major challenge in the field of forensic sciences and criminal investigation. Several laboratory techniques have recently been developed that offer a better contribution to the estimation of PMI, in addition to the traditional physical or physico-chemical (body cooling, lividity, radiocarbon dating, rigor mortis), chemical (autolysis), microbiological (putrefaction), entomological, as well as botanical parameters. Molecular biology (degradation pattern of macromolecules such as proteins, DNA, RNA), biochemical analysis of biological fluids (such as blood, cerebrospinal fluid, and vitreous humor), and immunohistochemistry are some of the most recent technological innovations. A systematic review of the literature was performed with the aim of presenting an up-to-date overview on the correlation between the immunohistochemical (IHC) expression of specific antigenic markers at different PMIs. The systematic review was performed according to PRISMA guidelines. Scopus and PubMed were used as search engines from January 1, 1998 to March 1, 2022 to evaluate the effectiveness of immunohistochemistry in estimating PMI. The following keywords were used: (immunohistochemical) OR (immunohistochemistry) AND (time since death) OR (post-mortem interval) OR (PMI). A total of 6571 articles were collected. Ultimately, 16 studies were included in this review. The results of this systematic review highlighted that IHC techniques, in association with traditional methods, add, in Bayesian terms, additional information to define a more accurate time of death and PMI. However, current IHC results are numerically limited and more data and studies are desirable in the near future.

Dysregulation of microRNAs and tRNA-derived ncRNAs in mesothelial and mesothelioma cell lines after asbestiform fiber exposure

Experimental evidence demonstrated that fluoro-edenite (FE) can develop chronic respiratory diseases and elicit carcinogenic effects. Environmental exposure to FE fibers is correlated with malignant pleural mesothelioma (MPM). An early diagnosis of MPM, and a comprehensive health monitoring of the patients exposed to FE fibers are two clinical issues that may be solved by the identification of specific biomarkers. We reported the microRNA (miRNA) and transfer RNA-derived non coding RNA (tRNA-derived ncRNA) transcriptome in human normal mesothelial and malignant mesothelioma cell lines exposed or not exposed to several concentration FE fibers. Furthermore, an interactive mesothelioma-based network was derived by using NetME tool. In untreated condition, the expression of miRNAs and tRNA-derived ncRNAs in tumor cells was significantly different with respect to non-tumor samples. Moreover, interesting and significant changes were found after the exposure of both cells lines to FE fibers. The network-based pathway analysis showed several signaling and metabolic pathways potentially involved in the pathogenesis of MPM. From papers analyzed by NetME, it is clear that many miRNAs can positively or negatively influence various pathways involved in MPM. For the first time, the analysis of tRNA-derived ncRNAs molecules in the context of mesothelioma has been made by using in vitro systems. Further studies will be designed to test and validate their diagnostic potential in high-risk individuals' liquid biopsies.

Environmental asbestos exposure and nonmalignant pleural findings: a retrospective evaluation of a five-year chest CT repository

This registry-based case-control study aimed to assess the association between asbestos deposits in the birthplace and/or residence and nonmalignant pleural findings, namely pleural plaques (PPs) and pleural thickening (PT), on chest CT scans. In total, 39,472 CT scans obtained over five years in a tertiary referral hospital in Ankara, Turkey, were evaluated. Cases involving patients with PP (n = 537), PT (n = 263), PP&PT (n = 69), and controls (n = 543) from the same study base without those conditions were included. Each case group was compared to controls using unconditional logistic regression. The presence of asbestos deposits in the district of birthplace (adjusted OR = 2.13, 95% CI: 1.35-3.37) and both birthplace and residence (aOR = 4.32, 95% CI: 2.26-8.27) was significantly related to the PPs. As the importance of environmental asbestos exposure in Turkey continues, future prospective studies could contribute to developing screening strategies.

Diagnostic and Prognostic Value of Three microRNAs in Environmental Asbestiform Fibers-Associated Malignant Mesothelioma

Fluoro-edenite (FE) is an asbestiform fiber identified in Biancavilla (Sicily, Italy). Environmental exposure to FE has been associated with a higher incidence of malignant mesothelioma (MM). The present study aimed to validate the predicted diagnostic significance of hsa-miR-323a-3p, hsa-miR-101-3p, and hsa-miR-20b-5p on a subset of MM patients exposed to FE and matched with healthy controls. For this purpose, MM tissues vs. nonmalignant pleura tissues were analyzed through droplet digital PCR (ddPCR) to evaluate differences in the expression levels of the selected miRNAs and their MM diagnostic potential. In addition, further computational analysis has been performed to establish the correlation of these miRNAs with the available online asbestos exposure data and clinic-pathological parameters to verify the potential role of these miRNAs as prognostic tools. ddPCR results showed that the three analyzed miRNAs were significantly down-regulated in MM cases vs. controls. Receiver operating characteristic (ROC) analysis revealed high specificity and sensitivity rates for both hsa-miR-323a-3p and hsa-miR-20b-5p, which thus acquire a diagnostic value for MM. In silico results showed a potential prognostic role of hsa-miR-101-3p due to a significant association of its higher expression and increased overall survival (OS) of MM patients.

Early Surgical Intervention Improves Survival in Acute Intestinal Ischemia in the Intensive Care Unit

The study is aimed at assessing whether the early surgical intervention improves survival in acute mesenteric ischemia with septic shock. A retrospective study design was applied to review the charts of patients admitted to the intensive care unit. The data were collected through a review of the full patient chart including physician and nursing notes, pathology reports, intraoperative findings, CT findings, and endoscopy. The diagnosis of AMI for each patient was determined through clinical presentation/endoscopic visualization/laboratory results/radiographic imaging, surgical exam (tissue or visual) and/or autopsy. Death and survival were evaluated between short and long-time-interval for septic shock groups using the chi-square test followed by calculating the P value. Total survival among the surgery group was 60 patients (95.24%) compared to 3 (4.76%) survival among patients who did not have surgery. The time from the onset of a shock to the time of surgical incision was calculated. The mean time to surgery was 17.7 hours. Total 65 patients (29.52%) had surgery between 4 and 12 hours from the onset of hypotension. Survivals among this group of patients were 41.7% (n = 25). The survival difference was statistically significant than died patients with respect to the time of surgical intervention (P = <0.001). Early removal of ischemic bowel in patients with AII-related surgery has improved survival.

Pathway of Inflammation due to Asbestiform Fiber “Fluoro-edenite” Exposure: An Update

:

FluorFluoro-edenite (FE) is an asbestos-like amphibole present in the bentonitic lavas extracted from a stone quarry in Biancavilla, a village sited in the Etnean Volcanic Area (Italy).o-edenite (FE) is an asbestos-like amphibole present in the bentonitic lavas extracted from a stone quarry in Biancavilla, a village sited in the Etnean Volcanic Area (Italy).

:

Thoracic pathologies are the results of excessive inflammatory processes that are the early response of the immune system to inhaled fibers. As demonstrated for asbestos, fibers may trigger immune system cells in an acute and/or chronic manner. This review aims to clarify the pathways of inflammation in workers exposed to FE fibers.

:

Based on the articles reviewed, it seems that a permanent stimulus created by repeatedly inhaling the FE fibers and their persistence in the body can act as a trigger both in promoting inflammatory processes and in the immunological induction of autoimmune disease.

Update of in vitro, in vivo and ex vivo fluoro-edenite effects on malignant mesothelioma: A systematic review (Review)

Fluoro-edenite (FE), asbestiform fiber found in Biancavilla (Sicily, Italy), presents various characteristics similar to the asbestos group, in particular two fibrous phases tremolite and actinolite. Indeed, epidemiological studies have shown that FE fibers have similar effects to those of asbestos fibers. Such studies have reported a high incidence of malignant mesothelioma (MM), an aggressive neoplasm of the serosal membranes lining the pleural cavity, in individuals residing there due to FE exposure in Biancavilla related to environmental contamination. Evidence has led to the classification of FE as a Group 1 human carcinogen by the International Agency for Research on Cancer (IARC). The aim of this systematic review is to compare the results achieved in in vitro, in vivo and ex vivo experimental studies involving FE in order to update the current knowledge on the pathogenesis and molecular mechanisms responsible for FE-mediated MM development as well as the availability of effective biomarkers for MM prevention and diagnosis. This review is focused on the pathophysiological mechanisms mediated by inflammation induced by FE fiber exposure and which are responsible for MM development. This review also discusses the discovery of new diagnostic and prognostic biomarkers for the management of this pathology. It is known that the risk of cancer development increases with chronic inflammation, arising from enhanced reactive oxygen species (ROS) and NO^• production stimulated by the body to remove exogenous agents, causing DNA damage and enhanced signal transduction that may lead to activation of oncogenes. Studies concerning MM biomarker discovery indicate that several biomarkers have been proposed for MM, but mesothelin is the only Food and Drug Administration (FDA)-approved biomarker for MM, with limitations. In recent studies, in silico analysis to identify selected miRNAs highly deregulated in cancer samples when compared with normal control have been developed. This in silico approach could represent an effort in the field of biomarker discovery for MM.

Modulation of microRNA expression levels after naturally occurring asbestiform fibers exposure as a diagnostic biomarker of mesothelial neoplastic transformation

Fluoro-edenite (FE) is a silicate mineral identified in the lava products of Monte Calvario from stone quarries located in the southeast of Biancavilla, a small city of the Etnean volcanic complex (Sicily, Italy). Inhalation of FE fibers has been associated with a higher incidence of Malignant Mesothelioma (MM), a highly aggressive neoplasm of the serosal membranes lining the pleural cavity. Only 5% of MM patients are diagnosed at an early stage and the median survival is approximate 6-12 months. Many diagnostic biomarkers have been proposed for MM. Several studies demonstrated that microRNAs (miRNAs) may be used as good non-invasive diagnostics, as well as prognostic biomarkers for various human diseases, including cancer. On these bases, the aim of the present study was to identify a set of miRNAs involved in the development and progression of MM and potentially used as diagnostic biomarkers. For these purposes, in silico analyses were performed on healthy/exposed to asbestos fibers subjects vs. patients with MM. These analyses revealed a set of miRNAs strictly involved in MM by merging the lists of miRNAs found differentially expressed in the three miRNA expression datasets analyzed. The result of these computational evaluations allowed the execution of functional in vitro experiments performed on normal pleural mesothelial cell line (MeT-5A) and MM cell line (JU77) in order to test the carcinogenetic effects and epigenetic modulation induced by FE exposure. The in vitro results showed that the expression levels of hsa-miR-323a-3p vary significantly in both supernatant- and cell-derived miRNAs derived from treated and untreated cells. Secreted and cellular hsa-miR-101-3p in MeT-5A treated with FE fibers and JU77 cells showed different trends of expression. As regard hsa-miR-20b-5p, there was no differential expression between secreted and cellular hsa-miR-20b-5p. This miRNA has been shown a significant up-regulation in JU77 cells vs. control and treated MeT-5A. As a future plan, translational analyses will be performed on a subset of patients chronically exposed to FE fibers to further verify the clinical role of such miRNAs in high-risk individuals and their possible use as biomarkers of FE exposure or MM early onset.

Defense and protection mechanisms in lung exposed to asbestiform fiber: the role of macrophage migration inhibitory factor and heme oxygenase-1

Fluoro-edenite (FE), an asbestiform fiber, is responsible for many respiratory pathologies: chronic obstructive diseases, pleural plaques, fibrosis, and malignant mesothelioma. Macrophage migration inhibitory factor (MIF) is one of the first cytokines produced in response to lung tissue damage. Heme oxygenase-1 (HO-1) is a protein with protective effects against oxidative stress. It is up regulated by several stimuli including pro-inflammatory cytokines and factors that promote oxidative stress. In this research, the in vivo model of sheep lungs naturally exposed to FE was studied in order to shed light on the pathophysiological events sustaining exposure to fibers, by determining immunohistochemical lung expression of MIF and HO-1. Protein levels expression of HO-1 and MIF were also evaluated in human primary lung fibroblasts after exposure to FE fibers in vitro. In exposed sheep lungs, MIF and HO-1 immunoexpression were spread involving the intraparenchymal stroma around bronchioles, interstitium between alveoli, alveolar epithelium and macrophages. High MIF immunoexpression prevails in macrophages. Similar results were obtained in vitro, but significantly higher values were only detected for HO-1 at concentrations of 50 and 100 μg/mL of FE fibers. MIF and HO-1 expressions seem to play a role in lung self-protection against uncontrolled chronic inflammation, thus counteracting the strong link with cancer development, induced by exposure to FE. Further studies will be conducted in order to add more information about the role of MIF and HO-1 in the toxicity FE-induced.

Fibulin-3 as biomarker of malignant mesothelioma

Many malignant diseases are associated with past asbestos exposure; the most lethal and strictly related to previous fiber exposure being malignant mesothelioma (MM). Effective preventive protocols may include sensitive and specific biomarkers. The role of Fb-3 has been recently investigated for MM early detection, but its role is still under debate. After an independent search for scientific literature, nine studies were included for a systematic review. Human Fb-3 levels seem to be able to separate healthy people with previous exposure to asbestiform fibers from MM patients. Fb-3 blood levels can distinguish MM effusions from other malignant and benign effusions. Furthers investigations on more significant groups of patients are desirable to validate and assess the validity of combining Fb-3 with other biomarkers.

Occupational exposure to fluoro-edenite and prevalence of anti-nuclear autoantibodies

An environmental contamination due to an asbestiform mineral fiber, fluoro-edenite (FE), caused a significantly increased mortality rate for malignant mesothelioma in Biancavilla, Italy. Exposure to fluoro-edenite has been associated with inflammatory processes as an early response to inhaled fibers. The aim was to explore prevalence of anti-nuclear autoantibodies (ANA) in a group of construction workers residing and working in the contaminated area. Prevalences for samples positive to ANA were 60% (n = 9) and 13% (n = 2), for exposed and nonexposed, respectively (p-value <0.05), the odds ratio was 9.75 (95% CI: 1.59-59.69). The significance of elevated ANAs in subjects exposed to fibers is unknown; additional studies may provide a better opportunity to establish a correlation between autoimmunity and environmental exposure.

Fibulin-3 immunoexpression in malignant mesothelioma due to fluoro-edenite: a preliminary report

An increased standardized incidence and mortality rate were reported due to malignant mesothelioma (MM) in Biancavilla. Environmental investigations showed the presence of an asbestiform fiber: fluoro-edenite (FE). MM develops with a latency of 20-60 years from exposure and specific and sensitive biomarkers are urgently needed. For this purpose, we evaluated Fibulin-3 (Fb-3) immunoexpression in human cases of MM related to FE exposure and its prognostic role. Immunohistochemical analysis of Fb-3 was carried out in eight MM patients resident in Biancavilla and the analysis showed evidence of environmental exposure to FE fibers. Six MM cases (3 epithelioid and 3 biphasic) showed a high immunoexpression of Fb-3 in neoplastic cells with nuclear and cytoplasmic localization. One epithelioid and one biphasic subtype did not show Fb-3 immunostaining. The results demonstrate the implication of Fb-3 in MM due to FE exposure and may possibly suggest its potential role as a diagnostic and prognostic marker.

Prevalence of anti-nuclear autoantibodies in subjects exposed to natural asbestiform fibers: a cross-sectional study

Fluoro-edenite (FE) is an asbestiform mineral fiber spotted in the lava rocks excavated from a stone quarry in Biancavilla (Italy). The derived material had been employed locally for building purposes. Previous studies found evidence that exposure to asbestos may induce autoimmunity, with frequency of anti-nuclear autoantibodies (ANA). The aim of this study was to explore the relationship between FE exposure and autoimmune responses in an exposed population. For the study, 60 subjects living in the area of Biancavilla and 60 subjects as control group were randomly invited to participate. A free medical check, including spirometry and a high-resolution computer tomography chest scan, was given to all participants. ANA were determined by indirect immunofluorescence. On medical check, no subject showed any sign and/or symptoms of illness. Prevalence for samples positive to ANA were 70% (n = 42) and 25% (n = 15), respectively, for exposed and non-exposed subjects (p < 0.05). The presence of pleural plaques (PP) was found in 21 (30%) of the exposed subjects and in 2 (3%) of the non-exposed participants. PP subjects were always ANAs positive. In conclusion, as already it was observed with exposure to asbestos fibers, levels of ANA seemed to significantly increase in subjects who had been exposed to FE. Furthermore, all subjects showing PP were also ANA-positive. This first finding in subjects exposed to FE should encourage researchers to further investigate associations between autoimmune unbalance and environmental exposure to asbestiform fibers.

Aquaporin-1 expression in fluoro-edenite-induced mesothelioma effusions: An approach by cell-block procedure

OBJECTIVE

Aquaporin 1 (AQP-1) is a water channel protein found in cell membranes, whose expression has been considered an independent favourable prognostic factor in pleural malignant mesothelioma (MM). The aim of this study was to evaluate the expression of AQP-1 and its prognostic value in a series of pleural MM effusions, from a geographical area with high concentrations of fluoro-edenite (FE).

METHODS

We selected 25 MM cases from Biancavilla (Italy), an area with high environmental concentrations of FE. Cytological samples, cell-blocks (CB), clinical and follow-up data were available for all cases. Immunohistochemistry for calretinin, CK5/6, WT1, CK7 and TTF1 was used on CB sections to confirm the cytological diagnosis of MM. Immunohistochemistry for AQP-1 was performed and high expression was defined when ≥50% of tumour cells showed linear and circumferential membranous staining.

RESULTS

The cohort included 16 men and nine women (median age: 67.5 years; range: 49-88 years). The median survival was 14 months (range 1.5-60 months), with a significant value (P = 0.006). All cases have been histologically confirmed and classified as epithelioid (16 cases), biphasic (seven cases) and sarcomatoid (two cases). AQP-1 high expression has been observed in 16 cases. Comparing AQP-1 high expression to the survival of corresponding patients, a significant association with a slight increased overall survival of 12 months has been demonstrated. Nine patients with a AQP-1 score less than 50% showed a shorter median overall survival (7 months).

CONCLUSIONS

AQP-1 high expression is detectable on cytological samples of FE-induced MM with a prognostic value.

Biomarkers for Early Diagnosis and Prognosis of Malignant Pleural Mesothelioma: The Quest Goes on

Malignant pleural mesothelioma (MM) is a highly aggressive tumor characterized by a poor prognosis. Although its carcinogenesis mechanism has not been strictly understood, about 80% of MM can be attributed to occupational and/or environmental exposure to asbestos fibers. The identification of non-invasive molecular markers for an early diagnosis of MM has been the subject of several studies aimed at diagnosing the disease at an early stage. The most studied biomarker is mesothelin, characterized by a good specificity, but it has low sensitivity, especially for non-epithelioid MM. Other protein markers are Fibulin-3 and osteopontin which have not, however, showed a superior diagnostic performance. Recently, interesting results have been reported for the HMGB1 protein in a small but limited series. An increase in channel proteins involved in water transport, aquaporins, have been identified as positive prognostic factors in MM, high levels of expression of aquaporins in tumor cells predict an increase in survival. MicroRNAs and protein panels are among the new indicators of interest. None of the markers available today are sufficiently reliable to be used in the surveillance of subjects exposed to asbestos or in the early detection of MM. Our aim is to give a detailed account of biomarkers available for MM.

Immunohistochemical Expression of Aquaporin-1 in Fluoro-Edenite-Induced Malignant Mesothelioma: A Preliminary Report

BACKGROUND

The immunohistochemical expression of aquaporin-1 (AQP1) in asbestos-related malignant pleural mesothelioma (MPM) is emerging as a useful prognostic indicator of improved survival. A significantly increased incidence of MPM in a small town in southern Italy was ascribed to exposure to fluoro-edenite (FE), a naturally occurring asbestos fiber. We investigated the immunohistochemical expression of AQP1 in patients affected by FE-related MPM; taking into consideration its suggested independent prognostic role, its possible correlation with clinicopathological parameters and patient outcome was also evaluated.

METHODS

Ten patients were selected for this study, as neoplastic tissue blocks, clinical and follow-up data were available. The immunohistochemical overexpression of AQP1 was defined as ≥50% of tumor cells showing membranous staining.

RESULTS

Six cases showed AQP1 expression in ≥50% of tumor cells; in this group, a significant association of AQP1 overexpression with an increased median overall survival (OS) of 26.3 months was observed. By contrast, four patients exhibited an AQP1 score of <50% of stained cells, with a shorter median OS of 8.9 months.

CONCLUSIONS

The present study represents further confirmation of the hypothesized prognostic role of AQP1, which seems a reliable prognostic indicator.

Analysis of fibulin-3 after exposure to asbestos-like fibers

A significantly increased incidence of malignant mesothelioma in Biancavilla (Sicily, Italy) has been ascribed to exposure to fluoro-edenite, a fibrous amphibole extracted from a local stone quarry. Fibulin-3 is a highly conserved glycoprotein proposed as a biomarker for malignant mesothelioma that belongs to the family of extracellular matrix proteins. Previous studies demonstrated high Fibulin-3 plasma levels in workers with pleural plaques exposed to fluoro-edenite. Therefore, in order to gain insight into the biomolecular mechanisms of fluoro-edenite toxicity, we performed the analysis of Fibulin-3 expression by immunohistochemistry in the lung samples derived from sheep belonging to the area of Biancavilla. Furthermore, an in vitro model of exposed fluoro-edenite fibroblasts was used to perform functional experiments to better understand the modulation of Fibulin-3 expression. The percentage of immunostained area by Fibulin-3 was very much higher in exposed lungs compared with non-exposed ones. The Fibulin-3 protein level was significantly expressed in primary human lung fibroblasts exposed to 50 and 100µg/ml of fluoro-edenite fibers for 72h, compared to the unexposed controls. The results from the present study further demonstrate the implication of Fibulin-3 during fluoro-edenite exposure. This would endorse our previous results regarding the use of Fibulin-3 as a possible screening biomarker for fluoro-edenite exposed individuals, thereby contributing to the monitoring of the population at risk. The present study also suggested that the Fibulin-3 overexpression may reflect a defensive response of the tissues after exogenous stimuli and may be implicated in cancer development, especially in the context of fluoro-edenite contamination. However, further studies are necessary in order to make Fibulin-3 a customized screening tool.

Immunological effects of occupational exposure to lead (Review)

It is well-known that occupational and environmental exposure to several factors, including benzene, heavy metals, chemicals and mineral fibers, is associated with the risk of developing a great number of diseases. Numerous studies have been carried out in order to investigate the mechanisms of toxicity of these substances, with particular regard to the possible toxic effects on the immune system. However, little is known about the influence of heavy metals, such as lead, on the immune system in human populations. Lead is a heavy metal still used in many industrial activities. Human exposure to lead can induce various biological effects depending upon the level and duration of exposure, such as toxic effects on haematological, cardiovascular, nervous and reproductive systems. Several studies demonstrated that exposure to lead is associated to toxic effects also on the immune system, thus increasing the incidence of allergy, infectious disease, autoimmunity or cancer. However, the effects of lead exposure on the human immune system are not conclusive, mostly in occupationally exposed subjects; nevertheless some immunotoxic abnormalities induced by lead have been suggested. In particular, in vivo, in vitro and ex vivo lead is able to improve T helper 2 (Th2) cell development affecting Th1 cell proliferation. Further studies are required to better understand the mechanisms of lead immunotoxicity and the ability of lead to affect preferentially one type of immune response.

Occupational exposure to Mount Etna's basaltic dust: Assessment of mutagenic and cytotoxic effects

Basalt and volcanic ash are natural constituents of the ground surrounding volcanic areas such as Mount Etna. The dust may be daily inhaled by the general population as well as by several types of workers, such as construction workers. In this experiment, we analyzed the potential mutagenic and cytotoxic effects of the materials used in construction industry, excavated from Mt. Etna. Ground basalt (A), volcanic ash (B), mixed basalt and cement (C) and cement (D) were studied with Ames test, for mutagenic assessment and with MMT assay for cytotoxic evaluation. The Ames test revealed that cement (sample D), showed a higher and significant mutagenicity than the samples A, B and C. MTT assay showed that samples C and D had a slightly more negative impact on cell viability than A and B. In conclusion, no particular risks seem to exist for construction industry workers, while the exploitation of cement and cement mixed with basalt seems to be a risk for workers, given the high percentage of silica and iron.

New insights on 'old' toxicants in occupational toxicology (Review)

In order to deliver the best possible working environment, it is essential to identify professional conditions that could be harmful for worker's health and prevent (or limit) the occurrence of such conditions. The appropriate use of personal protective equipment and the development of appropriate regulations allowed to reduce the prevalence of 'classic' occupational diseases, such as occupational hearing loss or asbestosis, just to name a few. Nowadays, environmental pollution seems to be one of the most relevant concerns for human and animal health, and toxicology is becoming one of the most prominent fields of interest in occupational settings. An increasing number of studies demonstrate that the presence of toxicants in the workplace could be responsible for the development of chronic diseases, even at doses that were considered 'safe'. The present review summarizes some of the most recent advancements in occupational toxicology, focusing on topics that have long been debated in the past and that have recently returned to the fore.

Lead exposure and plasma mRNA expression in ERBB2 gene

Epidemiologic data for carcinogenicity in those exposed to lead (Pb) suggests relations with cancers although the totality of the evidence is inconsistent. Alterations in the expression of ERBB receptors have been studied during the development and malignant transformation of different kinds of human tumors where they induce proliferation, angiogenesis and metastasis generation. Relevant clinical data demonstrate the role of ERBB2 receptors in the development and malignancy of human cancers. Therefore, the objective of the present investigation is to give more information on the link between plasma mRNA expression in ERBB2 gene and lead blood levels in a healthy population. Blood samples, socio‑demographic, exposure and health data were obtained from 48 healthy men. Real‑time polymerase chain reaction assays were performed to detect ERBB2 gene transcripts, ΔΔCt method was used to quantify gene expression. Pb blood level was assayed using high‑resolution sector field inductively coupled mass spectrometry and is expressed in µg/dl. Plasma mRNA expression in ERBB2 gene was 6.44±3.07 ΔΔCt; Pb blood levels was 16.07±6.74 µg/dl. Regression analysis revealed a significant association (r2=0.5345; p<0.0001) between Pb levels and mRNA expression in ERBB2. So far, it has still not been established if the expression of ERBB2 receptors is influenced by Pb exposure. On the base of the above reported data, we believe an in vitro study might be useful, to understand the molecular mechanisms implicated.

Immunomodulatory effects in workers exposed to naturally occurring asbestos fibers

Natural asbestiform fibers are defined 'naturally occurring asbestos' (NOA) and refer to the mineral as a natural component of soils or rocks. The release of NOA fibers into the air from rocks or soils by routine human activities or natural weathering processes represents a risk for human beings. Fluoro-edenite (FE) is a NOA fiber detected in the benmoreitic lava in the area of Biancavilla, South-west slope of Mt. Etna. The aim of the present study was to investigate FE immunotoxicity pathways in a group of 38 occupationally exposed construction workers, in order to find any biological markers of its effect. Subjects underwent respiratory function tests and HRCT total chest scanning. Serum IL-1β, IL-6, IL-8 and TNF-α were measured. The presence of PPs was significantly greater in subjects exposed than in the control (25 vs. 2). In subjects exposed to FE, IL-1β and TNF-α values were significantly higher than the controls. The previously observed increase of IL-1β and IL-18 showed a probable involvement of the proteic complex defined inflammosome by FE fibers.