The incidence of upper respiratory infections in children is related to the concentration of vanadium in indoor dust aggregates.

Background: It has been reported that the disease-initiated and disease-mediated effects of aerosol pollutants can be related to concentration, site of deposition, duration of exposure, as well as the specific chemical composition of pollutants. Objectives: To investigate the microelemental composition of dust aggregates in primary schools of Vilnius and determine trace elements related to acute upper respiratory infections among 6-to 11-year-old children. Methods: Microelemental analysis of aerosol pollution was performed using dust samples collected in the classrooms of 11 primary schools in Vilnius from 2016 to 2020. Sites included areas of its natural accumulation behind the radiator heaters and from the surface of high cupboards. The concentrations of heavy metals (Pb, W, Sb, Sn, Zr, Zn, Cu, Ni, Mn, Cr, V, and As) in dust samples were analyzed using a SPECTRO XEPOS spectrometer. The annual incidence rates of respiratory diseases in children of each school were calculated based on data from medical records. Results: The mean annual incidence of physician-diagnosed acute upper respiratory infections (J00-J06 according to ICD-10A) among younger school-age children was between 25.1 and 71.3% per school. A significant correlation was found between vanadium concentration and the number of episodes of acute upper respiratory infections during each study year from 2016 to 2020. The lowest was r = 0.67 (p = 0.024), and the highest was r = 0.82 (p = 0.002). The concentration of vanadium in the samples of dust aggregates varied from 12.7 to 52.1 parts per million (ppm). No significant correlations between the other trace elements and the incidence of upper respiratory infections were found, which could be caused by a small number of study schools and relatively low concentrations of other heavy metals found in the samples of indoor dust aggregates. Conclusion: A significant and replicable correlation was found between the concentration of vanadium in the samples of natural dust aggregates collected in primary schools and the incidence of acute upper respiratory infections in children. Monitoring the concentration of heavy metals in the indoor environment can be an important instrument for the prevention and control of respiratory morbidity in children.

Associations of miR-181a with Health-Related Quality of Life, Cognitive Functioning, and Clinical Data of Patients with Different Grade Glioma Tumors.

Gliomas are central nervous system tumors with a lethal prognosis. Small micro-RNA molecules participate in various biological processes, are tissue-specific, and, therefore, could be promising targets for cancer treatment. Thus, this study aims to examine miR-181a as a potent biomarker for the diagnosis and prognosis of glioma patients and, for the first time, to find associations between the expression level of miR-181a and patient quality of life (QoL) and cognitive functioning. The expression level of miR-181a was analyzed in 78 post-operative II-IV grade gliomas by quantitative real-time polymerase chain reaction. The expression profile was compared with patient clinical data (age, survival time after the operation, tumor grade and location, mutation status of isocitrate dehydrogenase 1 (IDH1), and promoter methylation of O-6-methylguanine methyltransferase). Furthermore, the health-related QoL was assessed using the Karnofsky performance scale and the quality of life questionnaires; while cognitive assessment was assessed by the Hopkins verbal learning test-revised, trail-making test, and phonemic fluency tasks. The expression of miR-181a was significantly lower in tumors of grade III and IV and was associated with IDH1 wild-type gliomas and a worse prognosis of patient overall survival. Additionally, a positive correlation was observed between miR-181a levels and functional status and QoL of glioma patients. Therefore, miR-181a is a unique molecule that plays an important role in gliomagenesis, and is also associated with changes in patients' quality of life.

Transcriptome-wide analysis of glioma stem cell specific m6A modifications in long-non-coding RNAs.

The interest in chemical RNA modifications is rapidly growing in the field of molecular biology. Dynamic and reversible alterations of N6-methyladenosine (m6A) RNA modification are responsible for a platter of structural and functional changes in healthy and cancerous cell states. Although many studies reported the link between tumor initiation/progression and m6A modulators, there are few studies exploring transcriptome-wide m6A profile of non-coding RNAs. The aim of current study was to identify glioma stem cell (GSC) specific m6A landscape of long non-coding RNAs (lncRNAs) applying MeRIP-seq approach. MeRIP-seq analysis assigned 77.9% of m6A peaks to mRNAs and 8.16% to lncRNAs. GSCs and differentiated cells showed 76.4% conservation of m6A peaks, while 19.4% were unique to GSCs. Seven novel GSC-specific m6A modified lncRNAs were identified: HRAT92, SLCO4A1-AS1, CEROX1, PVT1, AGAP2-AS1, MIAT, and novel lncRNA gene ENSG00000262223. Analysis disclosed a strong negative correlation between lncRNAs m6A modification rate and expression. MeRIP-seq analysis revealed m6A modifications on previously reported glioma-associated lncRNAs: LINC000461, HOTTIP, CRNDE, TUG1, and XIST. Moreover, current study disclosed that most highly m6A modified lncRNAs primarily contain m6A modifications close to 3' and 5' ends. Our results provide basis and insight for further studies of m6A modifications in non-coding transcriptome of GSCs.

Indoor air pollution effects on pediatric asthma are submicron aerosol particle-dependent.

The school environment is crucial for the child's health and well-being. On the other hand, the data about the role of school's aerosol pollution on the etiology of chronic non-communicable diseases remain scarce. This study aims to evaluate the level of indoor aerosol pollution in primary schools and its relation to the incidence of doctor's diagnosed asthma among younger school-age children. The cross-sectional study was carried out in 11 primary schools of Vilnius during 1 year of education from autumn 2017 to spring 2018. Particle number (PNC) and mass (PMC) concentrations in the size range of 0.3-10 µm were measured using an Optical Particle Sizer (OPS, TSI model 3330). The annual incidence of doctor's diagnosed asthma in each school was calculated retrospectively from the data of medical records. The total number of 6-11 years old children who participated in the study was 3638. The incidence of asthma per school ranged from 1.8 to 6.0%. Mean indoor air pollution based on measurements in classrooms during the lessons was calculated for each school. Levels of PNC and PMC in schools ranged between 33.0 and 168.0 particles/cm3 and 1.7-6.8 µg/m3, respectively. There was a statistically significant correlation between the incidence of asthma and PNC as well as asthma and PMC in the particle size range of 0.3-1 µm (r = 0.66, p = 0.028) and (r = 0.71, p = 0.017) respectively. No significant correlation was found between asthma incidence and indoor air pollution in the particle size range of 0.3-2.5 and 0.3-10 µm.   Conclusion: We concluded that the number and mass concentrations of indoor air aerosol pollution in primary schools in the particle size range of 0.3-1 µm are primarily associated with the incidence of doctor's diagnosed asthma among younger school-age children. What is Known: • Both indoor and outdoor aerosol pollution is associated with bronchial asthma in children. What is New: • The incidence of bronchial asthma among younger school age children is related to indoor air quality in primary schools. • Aerosol pollutants in the size range of 0.3-1 µm in contrast to larger size range particles can play major role in the etiology of bronchial asthma in children.

A SEMA3 Signaling Pathway-Based Multi-Biomarker for Prediction of Glioma Patient Survival.

Glioma is a lethal central nervous system tumor with poor patient survival prognosis. Because of the molecular heterogeneity, it is a challenge to precisely determine the type of the tumor and to choose the most effective treatment. Therefore, novel biomarkers are essential to improve the diagnosis and prognosis of glioma tumors. Class 3 semaphorin proteins (SEMA3) play an important role in tumor biology. SEMA3 transduce their signals by using neuropilin and plexin receptors, which functionally interact with the vascular endothelial growth factor-mediated signaling pathways. Therefore, the aim of this study was to explore the potential of SEMA3 signaling molecules for prognosis of glioma patient survival. The quantitative real-time PCR method was used to evaluate mRNA expression of SEMA3(A-G), neuropilins (NRP1 and NRP2), plexins (PLXNA2 and PLXND1), cadherins (CDH1 and CDH2), integrins (ITGB1, ITGB3, ITGA5, and ITGAV), VEGFA and KDR genes in 59 II-IV grade glioma tissues. Seven genes significantly associated with patient overall survival were used for multi-biomarker construction, which showed 64%, 75%, and 68% of accuracy of predicting the survival of 1-, 2-, and 3-year glioma patients, respectively. The results suggest that the seven-gene signature could serve as a novel multi-biomarker for more accurate prognosis of a glioma patient's outcome.

The Anti-Tumorigenic Activity of Sema3C in the Chick Embryo Chorioallantoic Membrane Model.

Sema3C protein, a member of the class 3 family of secreted semaphorins, play an important role in tumor development by regulating cell proliferation, migration, invasion, and angiogenesis processes. Depending on the type and malignancy grade of the tumor, Sema3C function remains controversial. In this study, we constructed a stably overexpressing Sema3C glioblastoma cell line U87 MG and tested it on the chicken embryo chorioallantoic membrane (CAM) model with the aim to reveal Sema3C protein function on angiogenesis process in ovo. Our experiments showed that Sema3C not only affects angiogenesis of CAM by inhibiting neovascularization but also acts as an anti-tumorigenic molecule by hampering U87 MG cell invasion into mesenchyme. The effects of Sema3C on CAM were similar to the effects of anti-epileptic drug sodium valproate (NaVP). Both, anti-angiogenic and anti-tumorigenic activities of Sema3C were enhanced by the treatment of NaVP and, importantly, were not attributed to the cytotoxic effects. Our studies suggest that Sema3C could be a promising target for glioblastoma treatment.

Metallothionein Genes are Highly Expressed in Malignant Astrocytomas and Associated with Patient Survival.

Gliomas are heterogeneous, primary brain tumours that originate from glial cells. The main type of gliomas is astrocytomas. There are four grades (I-IV) of astrocytoma malignancy. Astrocytoma grade IV known as glioblastoma multiforme (GBM) is the most common and aggressive type of astrocytic gliomas. Metallothioneins (MT) are low molecular weight, cysteine rich proteins encoded by a family of metallothionein (MT) genes. MT genes play a crucial role in carcinogenesis of diverse malignancies. We proposed MT genes as prognostic markers for malignant astrocytoma. MT1A, MT1E, MT1X, MT2, MT3 gene expression was elevated in grade IV astrocytomas (glioblastomas) as compared to astrocytomas grade I-III. Statistically significant differences were reached for MT1A and MT2 genes (Mann-Whitney test, p < 0.05). High MT1A, MT1X, MT2, MT3 genes expression was associated with shorter patient survival (Log-rank test, p < 0.05). MT1A gene promoter methylation was decreased in glioblastoma (57.6%) while the gene was highly methylated in grade II-III astrocytoma (from 66.7% to 83.3%) and associated with better patient survival (p < 0.05). MT1A gene methylation showed a trend of being associated with higher mRNA expression level in astrocytomas. Increased MT genes expression in grade IV astrocytomas as compared to I-III grade astrocytomas could be associated with malignant tumour behaviour and progression.

Signal transducer and activator of transcription 3 (STAT3) promoter methylation and expression in pituitary adenoma.

BACKGROUND: Pituitary adenoma (PA) is a benign brain tumor that can cause neurological, endocrinological and ophthalmological aberrations. Till now there is a need to identify factors that can influence the tumor invasiveness and recurrence. The aim of this study was to evaluate the associations between the signal transducer and activator of transcription 3 (STAT3) promoter methylation, mRNA expression and the invasiveness or recurrence of PAs and patient clinical characteristics. METHODS: Study participants comprised of 102 subjects with a diagnosis of PA: 54 functioning and 48 non-functioning, 58 invasive and 30 non-invasive PAs and 14 relapses. The bisulfite treatment of tumor DNA and methylation-specific polymerase chain reaction (MS-PCR) method was used to determine the STAT3 gene promoter methylation. For the STAT3 mRNA expression, the first-strand cDNA was produced from total RNA by using reverse transcriptase and quantitative real-time PCR (qRT-PCR) was performed. RESULTS: In 10.78% (11/102) of PA tissues STAT3 gene promoter was methylated. A gender of male and patient group older than 60 years were significantly associated with reduced STAT3 mRNA expression (Mann-Whitney test, p = 0.025, p = 0.047, respectively). However, no more statistical differences were found between STAT3 promoter methylation, mRNA expression and patient clinical characteristics or PA invasiveness or recurrence. CONCLUSIONS: Further investigations are needed to clarify the influence of STAT3 gene promoter methylation and mRNA expression changes in PAs.

N-myc downstream-regulated gene 2 (NDRG2) promoter methylation and expression in pituitary adenoma.

BACKGROUND: Pituitary adenoma (PA) is a benign primary tumor that arises from the pituitary gland and is associated with ophthalmological, neurological and endocrinological abnormalities. However, causes that increase tumor progressing recurrence and invasiveness are still undetermined. Several studies have shown N-myc downstream regulated gene 2 (NDRG2) as a tumor suppressor gene, but the role of NDRG2 gene in pituitary adenoma pathogenesis has not been elucidated. The aim of our research has been to examine NDRG2 mRNA expression in PA and to determine the associations between the NDRG2 gene epigenetic changes and the development of recurrence or invasiveness of PA and patient clinical data. METHODS: The MS-PCR was used for NDRG2 promoter methylation analysis and gene mRNA expression levels were evaluated by qRT-PCR in 68 non-functioning and 73 functioning adenomas. Invasiveness was evaluated using magnetic resonance imaging with Hardy's modified criteria. Statistical analysis was performed to find correlations between NDRG2 gene mRNA expression, promoter methylation and patient clinical characteristics and PA activity. RESULTS: The NDRG2 mRNA expression was significantly lower in the case of acromegaly (GH and IGF-1 hypersecretion) than in other diagnoses of PAs (p < 0.05). Also, the NDRG2 expression was significantly higher in prolactinoma (PRL hypersecretion) than in in other diagnoses of PAs (p < 0.05). The promoter of NDRG2 was methylated in 22.69% (12/58 functioning and 15/61 non-functioning) of patients with PA. However, the NDRG2 gene mRNA expression was not significantly related to its methylation status. Clinical factors, such as: age, gender, relapse and diagnoses of Cushing syndrome were of no significance for NDRG2 promoter methylation and mRNA expression levels, as well as secreting or non-secreting PAs and the invasiveness of PAs. CONCLUSION: The different NDRG2 promoter methylation and expression levels in PA samples showed tumor heterogeneity and indicates a potential role of this gene in pituitary adenoma pathogenesis, but the corresponding details require intensive research.

Testin (TES) as a candidate tumour suppressor and prognostic marker in human astrocytoma.

Astrocytomas are one of the most common brain tumours; however, the current methods used to characterize these tumours are inadequate. The establishment of molecular markers may identify variables required to improve tumour characterization and subtyping, and may aid to specify targets for improved treatment with essential prognostic value for patient survival. One such candidate is testin (TES), which was reported to have prognostic value for glioblastoma patients. However, the role of TES protein in gliomagenesis is currently unknown. In the present study, the methylation status of the TES promoter was investigated in post-operative astrocytoma tumours of different malignancy grade, and its association with the survival of astrocytoma patients was evaluated. In addition, the expression of TES protein was investigated in the same set of astrocytoma tumours tissue, and the association of protein expression with glioma patients survival was evaluated. The methylation status of TES was assessed by methylation-specific polymerase chain reaction in 138 different grade astrocytoma samples. Western blot analysis was used to characterize the expression pattern of TES in 86 different grade astrocytoma specimens: 13 of pathological grade I, 31 of pathological grade II, 17 of pathological grade III and 25 of pathological grade IV (glioblastoma). Statistical analyses were conducted to investigate the association between tumour molecular pattern, patient clinical variables and overall survival. The methylation analysis of the TES promoter exhibited a distinct profile between astrocytomas of different malignancy grade (P<0.001). Furthermore, gene promoter methylation was significantly associated with patients' age, survival and pathological grade (P<0.001). The protein expression level of TES was significantly lower in glioblastoma (grade IV astrocytoma) than in lower grade (II-III) astrocytoma tissue (P=0.028 and P=0.04, respectively). Additionally, short overall survival of patients was markedly associated with low TES protein expression (P=0.007). However, no association between TES methylation and TES protein expression was noticed. The present study demonstrated that decreased expression of TES may be important in tumour progression and prognosis in human astrocytomas. TES may be a useful marker for predicting the clinical outcome of astrocytoma patients.

MMP-14 and TGFß-1 methylation in pituitary adenomas.

Pituitary adenoma (PA) is one of the most common abnormalities in the sellar region. Despite the fact that PA is a benign monoclonal neoplasm, it can cause serious complications, including ophthalmological, neurological and endocrinological abnormalities. Currently, the causes that increase the progression of tumors are unknown. Epigenetic silencing of the matrix metalloproteinase-14 (MMP-14) and transforming growth factor beta-1 (TGFß-1) genes may be associated with the development of PA, since these genes are important in the processes of tumor metastasis and angiogenesis. The purpose of the present study was to determine if the methylation status of the MMP-14 and TGFß-1 promoters is associated with PA development. In the present study, 120 tissue samples of PA were used. The methylation status of the MMP-14 and TGFß-1 promoters was investigated by methylation specific-polymerase chain reaction. Statistical analysis was conducted to investigate the associations between the methylation status, age and gender of PA patients, PA tumoral activity, recurrence and invasiveness. The MMP-14 gene was methylated in 30.00% (17/56 functioning and 19/64 non-functioning) of patients with PA, while the TGFß-1 gene was methylated in 13.33% (9/56 functioning and 7/64 non-functioning) of patients with PA. It was also observed that promoter methylation of MMP-14 correlated with the male gender (58.8 vs. 35.7%, P=0.022), while unmethylated (non-silenced) MMP-14 correlated with the female gender (64.3 vs. 41.7%, P=0.027). Associations between the promoter methylation status of the MMP-14 and TGFß-1 genes and PA functioning or recurrence were not identified. The present study reveals that silencing of the MMP-14 gene correlates with patients' gender. However, MMP-14 and TGFß-1 promoter methylation cannot be considered as a prognostic marker in PAs.