A pilot study to evaluate the expression of microRNA­let­7a in patients with intestinal­type sinonasal adenocarcinoma.

Despite its histological resemblance to colorectal adenocarcinoma, there is little information about the molecular events involved in the pathogenesis of intestinal-type sinonasal adenocarcinoma (ITAC). The present study investigated the possible role and clinical value of microRNA (miR)-let-7a, a head and neck squamous cell carcinoma-related miR, in a well-characterized and homogeneous cohort of patients with ethmoidal ITAC associated with occupational exposure, treated by primary surgery. miR-let-7a expression levels were analyzed in 23 pairs of ethmoidal ITAC and adjacent normal formalin-fixed paraffin-embedded tissues by reverse transcription-quantitative PCR. The expression was evaluated in tumor and healthy tissues according to: Tumor grade (G) of differentiation and extension, and pTNM stage, and presence/absence of recurrence. Comparisons within and between groups were performed using two-tailed Student's paired t-test and one-way ANOVA with Tukey's post hoc test. P<0.05 was considered to indicate a statistically significant difference. miR-let-7a expression in ethmoidal ITAC tissues was significantly lower than that in adjacent normal tissues (P<0.05; mean expression level ± SD, 1.452707±1.4367189 vs. 4.094017±2.7465375). miR expression varied with pT stage. miR-let-7a was downregulated (P<0.05) in advanced stages (pT3-pT4) compared with earlier stages (pT1-pT2). Furthermore, downregulation of miR-let-7a in ITAC was associated with poorly-differentiated (G3) cancer (P<0.05). No other associations were observed between miR-let-7a expression and the other clinicopathological parameters, including disease-free survival. In conclusion, downregulation of miR-let-7a in ITAC was associated with advanced-stage (pT3 and pT4) and poorly-differentiated (G3) disease, suggesting that the mutation of this gene, combined with additional genetic events, could serve a role in ITAC pathogenesis.

AGO2-RIP-Seq reveals miR-34/miR-449 cluster targetome in sinonasal cancers.

Sinonasal tumours are heterogeneous malignancies, presenting different histological features and clinical behaviour. Many studies emphasize the role of specific miRNA in the development and progression of cancer, and their expression profiles could be used as prognostic biomarkers to predict the survival. Recently, using the next-generation sequencing (NGS)-based miRNome analysis the miR-34/miR-449 cluster was identified as miRNA superfamily involved in the pathogenesis of sinonasal cancers (SNCs). In the present study, we established an Argonaute-2 (AGO2): mRNA immunoprecipitation followed by high-throughput sequencing to analyse the regulatory role of miR-34/miR-449 in SNCs. Using this approach, we identified direct target genes (targetome), which were involved in regulation of RNA-DNA metabolic, transcript and epigenetic processes. In particular, the STK3, C9orf78 and STRN3 genes were the direct targets of both miR-34c and miR-449a, and their regulation are predictive of tumour progression. This study provides the first evidence that miR-34/miR-449 and their targets are deregulated in SNCs and could be proposed as valuable prognostic biomarkers.

ATG5 as biomarker for early detection of malignant mesothelioma.

OBJECTIVES: Malignant pleural mesothelioma (MPM) is an aggressive disease with grim prognosis due to lack of effective treatment options. Disease prediction in association with early diagnosis may both contribute to improved MPM survival. Inflammation and autophagy are two processes associated with asbestos-induced transformation. We evaluated the level of two autophagic factors ATG5 and HMGB1, microRNAs (miRNAs) such as miR-126 and miR-222, and the specific biomarker of MPM, soluble mesothelin related proteins (Mesothelin) in asbestos-exposed individuals, MPM patients, and healthy subjects. The performance of these markers in detecting MPM was investigated in pre-diagnostic samples of asbestos-subjects who developed MPM during the follow-up and compared for the three groups. RESULTS: The ATG5 best distinguished the asbestos-exposed subjects with and without MPM, while miR-126 and Mesothelin were found as a significant prognostic biomarker for MPM. ATG5 has been identified as an asbestos-related biomarker that can help to detect MPM with high sensitivity and specificity in pre-diagnostic samples for up to two years before diagnosis. To utilize this approach practically, higher number of cases has to be tested in order to give the combination of the two markers sufficient statistical power. Performance of the biomarkers should be confirmed by testing their combination in an independent cohort with pre-diagnostic samples.

Force-feeding malignant mesothelioma stem-cell like with exosome-delivered miR-126 induces tumour cell killing.

Malignant pleural mesothelioma (MPM) is an aggressive tumour resistant to treatments. It has been postulated that cancer stem cells (CSCs) persist in tumours causing relapse after multimodality treatment. In the present study, a novel miRNA-based therapy approach is proposed. MPM-derived spheroids have been treated with exosome-delivered miR-126 (exo-miR) and evaluated for their anticancer effect. The exo-miR treatment increased MPM stem-cell like stemness and inhibited cell proliferation. However, at a prolonged time, the up taken miR-126 was released by the cells themselves through exosomes; the inhibition of exosome release by an exosome release inhibitor GW4869 induced miR-126 intracellular accumulation leading to massive cell death and in vivo tumour growth arrest. Autophagy is involved in these processes; miR-126 accumulation induced a protective autophagy and the inhibition of this process by GW4869 generates a metabolic crisis that promotes necroptosis, which was associated with PARP-1 over-expression and cyt-c and AIF release. Here, for the first time, we proposed a therapy against CSCs, a heterogeneous cell population involved in cancer development and relapse.

Effects of Animal-Assisted Therapy (AAT) in Alzheimer's Disease: A Case Study.

Alzheimer's disease (AD) is a neurodegenerative disorder, characterized by cortical dementia and irreversibly progressive developments leading to a vegetative state and, finally, to death. Although many aspects of its etiology, diagnosis and treatment still remain obscure and the current approach to the disease mostly suffers from limited and low-efficiency therapeutic means, nevertheless, recent interventions have aimed at improving patients' quality of life through nonpharmacological approaches, including animal-assisted therapy (AAT), arousing growing interest. In order to assess the physiological and neuropsychological effects of AAT on AD, 24 residents of a rest house in northern Italy were enrolled. The intervention consisted of one 45-minute AAT session per week over ten weeks. Twelve residents (six AD and six non-AD) received AAT and twelve (six AD and six non-AD) were controls. In order to evaluate the physiological and clinical effect of AAT on AD residents, three cardiac parameters, including the systolic and diastolic blood pressure and heart rate, were measured. Moreover, the neurocognitive and depressive states were assessed by the Mini Mental State Examination and the Geriatric Depression Scale, respectively. Analyses were performed by a four-way ANOVA model (including two ways for repeated measures) considering each main effect and interaction possible in the design. Our findings, despite the small sample size, suggest that AAT has a positive significant effect on physiological parameters and neurocognitive impairment, while no effect was observed on the depression level.

Mitochondrial Function as Related to Psychological Distress in Health Care Professionals.

OBJECTIVE: The present study evaluated the association of psychological distress and radiation exposure as a work-related stressor with mitochondrial function in health care professionals. METHODS: Health care professionals at a regional hospital in Italy were evaluated for physical health and psychological measures using self-report questionnaires (n = 41; mean age = 47.6 [13.1] years; 66% women). In a second sample, individuals exposed to elevated levels of ionizing radiation (IR; likely effective dose exceeding 6 mSv/y; n = 63, mean age = 45.8 [8.8] years; 62% women) were compared with health care workers with low IR (n = 57; mean age = 47.2 [9.5] years; 65% women) because exposure to a toxic agent might act as a (work-related) stressor. Associations were examined between psychological factors (12-item General Health Questionnaire, Perceived Stress Scale), work ability (Work Ability Index), and IR exposure at the workplace with markers of mitochondrial function, including mitochondrial redox activity, mitochondrial membrane potential, mitochondrial DNA (mtDNA) copy number, biogenesis, and mtDNA damage response measured from peripheral blood mononuclear cells. RESULTS: All participants were in good physical health. Individuals reporting high levels of psychological distress showed lower mitochondrial biogenesis as indicated by peroxisome proliferator-activated receptor-γ coactivator 1-α and lower nuclear factor erythroid 2-related factor 2 (NRF2) expression (2.5 [1.0] versus 1.0 [0.9] relative expression [rel exp], p = .035, and 31.5 [5.0] versus 19.4 [6.9] rel exp, p = .013, respectively). However, exposure to toxic agents (IR) was primarily associated with mitochondrial metabolism and reduced mtDNA integrity. Participants with IR exposure displayed higher mitochondrial redox activity (4480 [1202] mean fluorescence intensity [MFI]/min versus 3376 [983] MFI/min, p < .001) and lower mitochondrial membrane potential (0.89 [0.09] MFI versus 0.95 [0.11] MFI, p = .001), and reduced mtDNA integrity (1.18 [0.21] rel exp versus 3.48 [1.57] rel exp, p < .001) compared with nonexposed individuals. CONCLUSIONS: This study supports the notion that psychological distress and potential stressors related to toxic agents might influence various aspects of mitochondrial biology, and that chronic stress exposure can lead to molecular and functional recalibrations among mitochondria.

MiRNome analysis identifying miR-205 and miR-449a as biomarkers of disease progression in intestinal-type sinonasal adenocarcinoma.

BACKGROUND: Patients with intestinal-type sinonasal adenocarcinoma (ITAC) have an unfavorable prognosis, and new diagnostic and therapeutic approaches are needed to improve clinical management. METHODS: Next-generation sequencing-based miRNome analysis was performed on 43 ITAC patients who underwent surgical resection, and microRNA (miRNA) data were obtained from 35 cases. Four miRNAs were identified, and their expression levels were detected by reverse-transcription quantitative polymerase chain reaction and related to the relevant patient outcome. Overall survival and disease-free survival rates were evaluated through the Kaplan-Meier method and log-rank test, and multivariate analysis was performed by means of Cox proportional hazard analysis. RESULTS: High levels of miR-205 and miR-34c/miR-449 cluster expression were associated with an increased recurrence risk and, therefore, a worse prognosis. Multivariate analysis confirmed that miR-205 and miR-449 were significant prognostic predictors. CONCLUSIONS: A high expression of miR-205 and miR-449 is independent predictors of poor survival for ITAC patients.

BRCA-associated protein 1 (BAP1) and miR-31 combination predicts outcomes in epithelioid malignant pleural mesothelioma.

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive disease, with few available treatment options. Identification of novel prognostic and predictive biomarkers is a priority. In MPM patients, BRCA-associated protein 1 (BAP1) alterations are detected in about 60% of cases and miR-31 seems to be involved in BAP1 regulation at post-transcriptional level. The aim of this study was to evaluate the interaction between BAP1 and miR-31 in MPM and their prognostic role in MPM. METHODS: The expression of BAP1 and miR-31 was analyzed in tissues of 55 MPM patients treated with first-line chemotherapy. Overall survival (OS) and progression-free survival (PFS) were assessed by Kaplan-Meier method and Log-rank test was used to investigate differences among subgroups. Multivariate Cox regression analysis was used to evaluate independent predictors of survival. RESULTS: In the whole cohort, loss of BAP1 was associated with a significant improvement in OS, but not in PFS. Lower miR-31 levels were detected in epithelioid MPM (e-MPM) compared to the non-epithelioid subtypes and resulted associated with BAP1 loss. By looking at the e-MPM subgroup, loss of BAP1 was not able to predict clinical outcome. Conversely, miR-31 levels were significantly associated with PFS (P=0.028), but not with OS (P=0.059). By combining the two biomarkers, e-MPM patients with BAP1 loss/low miR-31 levels showed a better prognosis compared to the ones with BAP1 retained/high miR-31 levels (median OS 22.6 vs. 17.0 months, P=0.017 and median PFS 8.7 vs. 5.1 months, P=0.020). The BAP1 and miR-31 combination was confirmed at multivariate analysis as an independent prognostic factor for e-MPM patients. CONCLUSIONS: In this preliminary study, we found that the prognostic stratification of e-MPM patients may be improved by simultaneously assessing of BAP1 status and miR-31 levels. The two-biomarker score is useful to identify a subgroup of e-MPM tumors characterized by BAP1 retained and high miR-31 levels with worse clinical outcome.

NGS-based miRNome identifies miR-449 cluster as marker of malignant transformation of sinonasal inverted papilloma.

OBJECTIVE: identification of the miRNA expression profile in sinonasal inverted papilloma (SNIP) as a tool to evaluate the risk of transformation into sinonasal squamous cell carcinoma (SNSCC). MATERIALS AND METHODS: paired tumour tissues and adjacent normal tissues were obtained from SNIP and SNSCC patients who had undergone surgical resection and used for next-generation sequencing (NGS)-based miRNome analysis. SNIP tissues with concomitant dysplasia (SNIP-DISP) were used as malignant transition samples. By comparing the deregulated miRNAs in SNIP and SNSCC, an miRNA cluster was identified and its physio- and clinical-pathological value was predicted. RESULTS: NGS identified 54 miRNAs significantly down- and upregulated in SNIP. Among them, the miR-449 cluster was upregulated in SNIP and could differentiate the benign tumour from normal tissue. Notably, the miR-449 cluster was found to be significantly underexpressed in SNSCC, and the cluster markedly changed in SNIP during the malignant transition into SNSCC. miRNA enrichment analysis and GO analysis revealed that miR-449 is involved in apoptotic and cell proliferation pathways. CONCLUSIONS: Our findings suggest that miR-449 may be involved in the molecular pathogenesis of SNIP and its malignant transformation into SNSCC. miR-449 might therefore be a useful tumour biomarker in patients with SNIP and may also have the potential to be used as a tool for detecting and monitoring the course of the possible malignant transformation.

A Priori Activation of Apoptosis Pathways of Tumor (AAAPT) technology: Development of targeted apoptosis initiators for cancer treatment.

Cancer cells develop tactics to circumvent the interventions by desensitizing themselves to interventions. Amongst many, the principle routes of desensitization include a) activation of survival pathways (e.g. NF-kB, PARP) and b) downregulation of cell death pathways (e.g. CD95/CD95L). As a result, it requires high therapeutic dose to achieve tumor regression which, in turn damages normal cells through the collateral effects. Methods are needed to sensitize the low and non-responsive resistant tumor cells including cancer stem cells (CSCs) in order to evoke a better response from the current treatments. Current treatments including chemotherapy can induce cell death only in bulk cancer cells sparing CSCs and cancer resistant cells (CRCs) which are shown to be responsible for high recurrence of disease and low patient survival. Here, we report several novel tumor targeted sensitizers derived from the natural Vitamin E analogue (AMP-001-003). The drug design is based on a novel concept "A priori activation of apoptosis pathways of tumor technology (AAAPT) which is designed to activate specific cell death pathways and inhibit survival pathways simultaneously and selectively in cancer cells sparing normal cells. Our results indicate that AMP-001-003 sensitize various types of cancer cells including MDA-MB-231 (triple negative breast cancer), PC3 (prostate cancer) and A543 (lung cancer) cells resulting in reducing the IC-50 of doxorubicin in vitro when used as a combination. At higher doses, AMP-001 acts as an anti-tumor agent on its own. The synergy between AMP-001 and doxorubicin could pave a new pathway to use AAAPT leading molecules as neoadjuvant to chemotherapy to achieve better efficacy and reduced off-target toxicity compared to the current treatments.

Questioning the prognostic role of BAP-1 immunohistochemistry in malignant pleural mesothelioma: A single center experience with systematic review and meta-analysis.

INTRODUCTION: The prognostic role of BRCA1 associated protein-1 (BAP1) expression in malignant pleural mesothelioma (MPM) is a matter of debate. We aimed to clarify whether MPM patients with loss of BAP1 expression have better overall survival (OS) compared to BAP1 positive patients. METHODS: BAP1 immunohistochemical staining of tumor samples from 60 MPM patients treated at our institution with first-line chemotherapy was evaluated. A systematic literature search was also performed. Only cohort studies that investigated BAP1 by immunohistochemistry (IHC) and reported hazard ratio (HR) values for OS obtained through multivariate analysis (or adjusted for histotype) were considered. A dataset comprising 638 MPM patients was added to our cohort and included in the meta-analysis. RESULTS: In our cohort, 23 samples (38 %) were BAP1 positive/retained (≥1 %) and 37 samples (62 %) were BAP1 negative/loss. BAP1 loss was associated with epithelioid histotype (p 0.01). Median OS times were 14.8 months (95 % CI: 10.7-29.3) and 18.1 months (95 % CI: 11.2-25.8) for negative and positive BAP1 expression, respectively (p 0.2). At multivariate analysis, again no differences were observed among the two groups (p 0.81). Similarly, the meta-analysis consisting of 698 patients showed no difference in terms of OS according to BAP1 status (HR 1.11; 95 % CI, 0·76-1·61; p 0.60). CONCLUSIONS: BAP1 expression is not an independent prognostic factor for MPM patients and it should not be considered without taking into account tumor histotype. Future studies should investigate its predictive role in patients treated with new emerging therapies such as immunotherapy.

Mechanism of miR-222 and miR-126 regulation and its role in asbestos-induced malignancy.

MiR-222 and miR-126 are associated with asbestos exposure and the ensuing malignancy, but the mechanism(s) of their regulation remain unclear. We evaluated the mechanism by which asbestos regulates miR-222 and miR-126 expression in the context of cancer etiology. An 'in vitro' model of carcinogen-induced cell transformation was used based on exposing bronchial epithelium BEAS-2B cells to three different carcinogens including asbestos. Involvement of the EGFR pathway and the role of epigenetics have been investigated in carcinogen-transformed cells and in malignant mesothelioma, a neoplastic disease associated with asbestos exposure. Increased expression of miR-222 and miR-126 were found in asbestos-transformed cells, but not in cells exposed to arsenic and chrome. Asbestos-mediated activation of the EGFR pathway and macrophages-induced inflammation resulted in miR-222 upregulation, which was reversed by EGFR inhibition. Conversely, asbestos-induced miR-126 expression was affected neither by EGFR modulation nor inflammation. Rather than methylation of the miR-126 host gene EGFL7, epigenetic mechanism involving DNMT1- and PARP1-mediated chromatin remodeling was found to upregulate of miR-126 in asbestos-exposed cells, while miR-126 was downregulated in malignant cells. Analysis of MM tissue supported the role of PARP1 in miR-126 regulation. Therefore, activation of the EGFR pathway and the PARP1-mediated epigenetic regulation both play a role in asbestos-induced miRNA expression, associated with in asbestos-induced carcinogenesis and tumor progression.

Epigenetic Regulation of miRNA Expression in Malignant Mesothelioma: miRNAs as Biomarkers of Early Diagnosis and Therapy.

Asbestos exposure leads to epigenetic and epigenomic modifications that, in association with ROS-induced DNA damage, contribute to cancer onset. Few miRNAs epigenetically regulated in MM have been described in literature; miR-126, however, is one of them, and its expression is regulated by epigenetic mechanisms. Asbestos exposure induces early changes in the miRNAs, which are reversibly expressed as protective species, and their inability to reverse reflects the inability of the cells to restore the physiological miRNA levels despite the cessation of carcinogen exposure. Changes in miRNA expression, which results from genetic/epigenetic changes during tumor formation and evolution, can be detected in fluids and used as cancer biomarkers. This article has reviewed the epigenetic mechanisms involved in miRNA expression in MM, focusing on their role as biomarkers of early diagnosis and therapeutic effects.

Biological Effects of Ciliary Neurotrophic Factor on hMADS Adipocytes.

Administration of ciliary neurotrophic factor (CNTF) to experimental animals exerts anti-obesity effects by acting on multiple targets. In white adipose tissue CNTF reduces lipid content, promotes fatty acid (FA) oxidation and improves insulin sensitivity. This study was performed to establish whether CNTF exerts similar effects on human white adipocytes. To this end, adipose differentiation was induced in vitro in human multipotent adipose-derived stem (hMADS) cells. CNTF receptor α (CNTFRα) expression was assessed in hMADS cells and adipocytes by qRT-PCR, Western blotting, and immunocytochemistry. After administration of human recombinant CNTF, signaling pathways and gene expression were evaluated by Western blotting and qRT-PCR. Glucose uptake was assessed by measuring 2-nitrobenzodeoxyglucose uptake with a fluorescence plate reader. Lastly, CNTF-induced anti-inflammatory responses were evaluated in hMADS adipocytes stressed with tumor necrosis factor α (TNFα) for 24 h. Results showed that CNTFRα protein expression was higher in undifferentiated hMADS cells than in hMADS adipocytes, where it was however clearly detectable. In hMADS adipocytes, 1 nM CNTF strongly activated the JAK-STAT3 (Janus kinase-signaling transducer and activator of transcription 3) pathway and acutely and transiently activated the AMPK (AMP-activated protein kinase) and AKT (protein kinase B) pathways. Acute CNTF treatment for 20 min significantly increased basal glucose uptake and was associated with increased AKT phosphorylation. Longer-term (24 and 48 h) treatment reduced the expression of lipogenic markers (FA synthase and sterol regulatory element-binding protein-1) and increased the expression of lipolytic [hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL)] and mitochondrial (peroxisome proliferator-activated receptor γ coactivator-1α and carnitine palmitoyltransferase 1) markers. In TNFα-treated hMADS adipocytes, CNTF significantly reduced the expression of monocyte chemoattractant protein 1 and TNFα-induced AKT inhibition. Collectively, these findings demonstrate for the first time that CNTF plays a role also in human adipocytes, driving their metabolism toward a less lipid-storing and more energy-consuming phenotype.

Exosomal transfer of miR-126 promotes the anti-tumour response in malignant mesothelioma: Role of miR-126 in cancer-stroma communication.

MiR-126 has been shown to suppress malignant mesothelioma (MM) by targeting cancer-related genes without inducing toxicity or histopathological changes. Exosomes provide the opportunity to deliver therapeutic cargo to cancer stroma. Here, a tumour stromal model composed of endothelial cells (HUVECs), fibroblasts (IMR-90 cells), non-malignant mesothelial cells (Met-5A cells) and MM cells (H28 and MM-B1 cells) was used. The cells were treated with exosomes from HUVECs carrying endogenous (exo-HUVEC) and enriched miR-126 (exo-HUVECmiR-126), and the uptake/turnover of exosomes; miR-126 distribution within the stroma; and effect of miR-126 on cell signalling, angiogenesis and cell proliferation were evaluated. Based on the sensitivity of MM cells to exo-HUVEC miR-126 treatment, miR-126 was distributed differently across stromal cells. The reduced miR-126 content in fibroblasts in favour of endothelial cells reduced angiogenesis and suppressed cell growth in an miR-126-sensitive environment. Conversely, the accumulation of miR-126 in fibroblasts and the reduced level of miR-126 in endothelial cells induced tube formation in an miR-126-resistant environment via VEGF/EGFL7 upregulation and IRS1-mediated cell proliferation. These findings suggest that transfer of miR-126 via HUVEC-derived exosomes represents a novel strategy to inhibit angiogenesis and cell growth in MM.

Effect of different anaesthetic techniques on gene expression profiles in patients who underwent hip arthroplasty.

OBJECTIVES: To investigate the modulation of genes whose expression level is indicative of stress and toxicity following exposure to three anaesthesia techniques, general anaesthesia (GA), regional anaesthesia (RA), or integrated anaesthesia (IA). METHODS: Patients scheduled for hip arthroplasty receiving GA, RA and IA were enrolled at Rizzoli Orthopaedic Institute of Bologna, Italy and the expression of genes involved in toxicology were evaluated in peripheral blood mononuclear cells (PBMCs) collected before (T0), immediately after surgery (T1), and on the third day (T2) after surgery in association with biochemical parameters. RESULTS: All three anaesthesia methods proved safe and reliable in terms of pain relief and patient recovery. Gene ontology analysis revealed that GA and mainly IA were associated with deregulation of DNA repair system and stress-responsive genes, which was observed even after 3-days from anaesthesia. Conversely, RA was not associated with substantial changes in gene expression. CONCLUSIONS: Based on the gene expression analysis, RA technique showed the smallest toxicological effect in hip arthroplasty. TRIAL REGISTRATION: ClinicalTrials.gov number NCT03585647.

Four-miRNA Signature to Identify Asbestos-Related Lung Malignancies.

BACKGROUND: Altered miRNA expression is an early event upon exposure to occupational/environmental carcinogens; thus, identification of a novel asbestos-related profile of miRNAs able to distinguish asbestos-induced cancer from cancer with different etiology can be useful for diagnosis. We therefore performed a study to identify miRNAs associated with asbestos-induced malignancies. METHODS: Four groups of patients were included in the study, including patients with asbestos-related (NSCLCAsb) and asbestos-unrelated non-small cell lung cancer (NSCLC) or with malignant pleural mesothelioma (MPM), and disease-free subjects (CTRL). The selected miRNAs were evaluated in asbestos-exposed population. RESULTS: Four serum miRNAs, that is miR-126, miR-205, miR-222, and miR-520g, were found to be implicated in asbestos-related malignant diseases. Notably, increased expression of miR-126 and miR-222 were found in asbestos-exposed subjects, and both miRNAs are involved in major pathways linked to cancer development. Epigenetic changes and cancer-stroma cross-talk could induce repression of miR-126 to facilitate tumor formation, angiogenesis, and invasion. CONCLUSIONS: This study indicates that miRNAs are potentially involved in asbestos-related malignancies, and their expression outlines mechanism(s) whereby miRNAs may be involved in an asbestos-induced pathogenesis. IMPACT: The discovery of a miRNA panel for asbestos-related malignancies would impact on occupational compensation and may be utilized for screening asbestos-exposed populations.

MiR-126 in intestinal-type sinonasal adenocarcinomas: exosomal transfer of MiR-126 promotes anti-tumour responses.

BACKGROUND: Intestinal-type sinonasal adenocarcinomas (ITACs) are aggressive malignancies related to wood dust and leather exposure. ITACs are generally associated with advanced stage at presentation due to the insidious growth pattern and non-specific symptoms. Therefore, biomarkers that can detect the switch from the benign disease to malignancy are needed. Essential for tumour growth, angiogenesis is an important step in tumour development and progression. This process is strictly regulated, and MiR-126 considered its master modulator. METHODS: We have investigated MiR-126 levels in ITACs and compared them to benign sinonasal lesions, such as sinonasal-inverted papillomas (SIPs) and inflammatory polyps (NIPs). The tumour-suppressive functions of MiR-126 were also evaluated. RESULTS: We found that MiR-126 can significantly distinguish malignancy from benign nasal forms. The low levels of MiR-126 in ITACs point to its role in tumour progression. In this context, restoration of MiR-126 induced metabolic changes, and inhibited cell growth and the tumorigenic potential of MNSC cells. CONCLUSIONS: We report that MiR-126 delivered via exosomes from endothelial cells promotes anti-tumour responses. This paracrine transfer of MiRs may represent a new approach towards MiR-based therapy.

DNA damage response in workers exposed to low-dose ionising radiation.

OBJECTIVE: Medical personnel using radiation for diagnosis and therapeutic purposes are potentially at risk of cancer development. In this study, the effect of ionising radiation (IR) exposure was evaluated as DNA damage response (DDR) in the circulating cells of occupationally exposed subjects. METHODS: The study population consisted of IR-exposed workers included both in group B (effective dose ranging between 0.04 and 6 mSv/year) and group A (probable effective dose exceeding 6 mSv/year), and the control group consisted of healthy individuals who had never been occupationally exposed to IR or other known carcinogenic agents. DNA damage (single-strand breaks, oxidised purine and pyrimidine bases) and DNA repair (t1/2, half time to repair DNA damage, amount of repaired DNA and DNA repair activity) were measured in lymphocytes using the comet assay. To evaluate the influence of IR doses and genetic predisposition to cancer, the enrolled population was stratified according to IR exposure level and family history of cancer. RESULTS: Increased DNA repair activity was found in IR-exposed group, and only subjects highly exposed to IR doses accumulated DNA damage in their circulating cells, thus supporting the hypothesis of 'radiation hormesis'. A significant increase in DNA damage accumulation and a reduced 8-oxoguanine glycosylase 1-dependent DNA repair activity were found in IR-exposed subjects with cancer cases across their family. CONCLUSION: Our results indicate that chronic exposure to a low dose of IR in occupational settings induces DDR in exposed subjects and may be mutagenic in workers with family history of cancer, suggesting that periodic surveillance might be advisable, along with exposure monitoring.

Mechanism underlying the effect of long-term exposure to low dose of pesticides on DNA integrity.

Pesticides, including herbicides, insecticides and fungicides, are widely used in intensive agriculture. Recently, the long-term effects of pesticide exposure were found to be associated with many diseases. In this study, we evaluated the long-term effect of low-level exposure to a mixture of pesticides on DNA damage response (DDR) in relation to individual detoxifying variability. A residential population chronically exposed to pesticides was enrolled, biological/environmental pesticide levels; paroxonase 1 (PON-1) activity and 192 Q/R polymorphism and DDR were evaluated at three different periods of pesticide exposure. OGG1-dependent DNA repair activity was decreased in relation to pesticide exposure. The increase of DNA lesions and pesticide levels in the intensive pesticide-spraying period was independent on PON-1 activity. Next, human bronchial epithelial and neuronal cells were used as a model for in vitro evaluation of the mechanistic effect of pesticides. Pesticides induced mitochondrial dysfunction leading to ROS formation. ROS from mitochondria induced DNA damage, which in turn induced OGG1-dependent DNA repair activity through 8-oxoguanine DNA glycosylase 1 (OGG1) expression and activation. Even though OGG1 was overexpressed, an inhibition of its activity, associated with DNA lesion accumulation, was found at prolonged pesticide-exposure. A post-translational regulation of OGG1 by pesticide may be postulated. Taken together, long-term exposure to low-levels of pesticides affects DDR resulting in accumulation of DNA lesions that eventually may lead to cancer or neurological disorders.