Potential Role of Selected miRNAs in the Pathogenesis of Autoimmune Thyroid Diseases in Children and Adolescents

BACKGROUND

Many epigenetic factors, including microRNAs, are involved in the process of changing gene expressions. Small non-coding RNA molecules, called miRNAs, are responsible for regulating gene translation by silencing or degrading target mRNAs. It is acknowledged that for many diseases, they may be novel diagnostic and prognostic biomarkers. Patients with autoimmune thyroid diseases are more likely to develop nodules in the thyroid tissue, and Hashimoto's thyroiditis and Graves' disease predispose patients to thyroid cancer. We evaluated the concentrations of microRNA molecules (miR-15a-5p, miR-126-3p, miR-142-5p, miR-21-5p, miR-150-5p) in the blood of children with thyroid disorders. In addition, we wished to identify molecules whose change in concentration predisposes to the development of thyroid cancer.

AIM

The aim of this study is to evaluate selected epigenetic elements by analyzing the levels of miR-15a-5p, miR-126-3p, miR-142-5p, miR-150-5p and miR-21-5p in the blood of pediatric patients with Graves' disease (n = 25), Hashimoto's thyroiditis (n = 26) and thyroid nodular disease (n = 20) compared to a control group of healthy children (n = 17).

MATERIALS AND METHODS

The study consists of groups of children and adolescents aged 10-18 years with autoimmune thyroid disease, with thyroid nodular disease compared to a control group. The miR-15a-5p, miR-126-3p, miR-142-5p, miR-21-5p and miR-150-5p molecules were determined through an immunoenzymatic assay using BioVendor reagents.

RESULTS

There is a statistically significant decrease in the expression of the miR-15a-5p in children with Graves' disease (21.61 vs. 50.22 amol/μL, p = 0.03) and in patients with thyroid nodular disease compared to controls (20.23 vs. 50.22 amol/μL, p = 0.04). Higher levels of the miR-142-5p molecule are found in patients with thyroid disease (with GD-3.8 vs. 3.14 amol/μL, p = 0.01; with HT-3.7 vs. 3.14 amol/μL, p = NS, with thyroid nodular disease-4.16 vs. 3.14 amol/μL, p = 0.04). Lower levels of miR-126-3p were noted in the GD group compared to the control group (7.09 vs. 7.24 amol/μL, p = 0.02). No statistically significant changes in the expressions of miR-150-5p and miR-21-5p molecules were observed in the study groups.

CONCLUSIONS

1. The overexpression of the miR-142-5p molecule occurs in children and adolescents with thyroid diseases. 2. Decreased blood levels of miR-15a-5p predispose patients to the formation of focal lesions in the thyroid gland. 3. Identifying a lower expression of the miR-126-3p molecule in the blood of children with GD requires careful follow-up for the development of focal lesions in the thyroid gland and evaluation for their potential malignancy.

Six-Gene Signature for Differential Diagnosis and Therapeutic Decisions in Non-Small-Cell Lung Cancer-A Validation Study

Non-small-cell lung cancer (NSCLC) poses a challenge due to its heterogeneity, necessitating precise histopathological subtyping and prognostication for optimal treatment decision-making. Molecular markers emerge as a potential solution, overcoming the limitations of conventional methods and supporting the diagnostic-therapeutic interventions. In this study, we validated the expression of six genes (MIR205HG, KRT5, KRT6A, KRT6C, SERPINB5, and DSG3), previously identified within a 53-gene signature developed by our team, utilizing gene expression microarray technology. Real-time PCR on 140 thoroughly characterized early-stage NSCLC samples revealed substantial upregulation of all six genes in squamous cell carcinoma (SCC) compared to adenocarcinoma (ADC), regardless of clinical factors. The decision boundaries of the logistic regression model demonstrated effective separation of the relative expression levels between SCC and ADC for most genes, excluding KRT6C. Logistic regression and gradient boosting decision tree classifiers, incorporating all six validated genes, exhibited notable performance (AUC: 0.8930 and 0.8909, respectively) in distinguishing NSCLC subtypes. Nevertheless, our investigation revealed that the gene expression profiles failed to yield predictive value regarding the progression of early-stage NSCLC. Our molecular diagnostic models manifest the potential for an exhaustive molecular characterization of NSCLC, subsequently informing personalized treatment decisions and elevating the standards of clinical management and prognosis for patients.

Serum Insights: Leveraging the Power of miRNA Profiling as an Early Diagnostic Tool for Non-Small Cell Lung Cancer

Non-small cell lung cancer is the predominant form of lung cancer and is associated with a poor prognosis. MiRNAs implicated in cancer initiation and progression can be easily detected in liquid biopsy samples and have the potential to serve as non-invasive biomarkers. In this study, we employed next-generation sequencing to globally profile miRNAs in serum samples from 71 early-stage NSCLC patients and 47 non-cancerous pulmonary condition patients. Preliminary analysis of differentially expressed miRNAs revealed 28 upregulated miRNAs in NSCLC compared to the control group. Functional enrichment analyses unveiled their involvement in NSCLC signaling pathways. Subsequently, we developed a gradient-boosting decision tree classifier based on 2588 miRNAs, which demonstrated high accuracy (0.837), sensitivity (0.806), and specificity (0.859) in effectively distinguishing NSCLC from non-cancerous individuals. Shapley Additive exPlanations analysis improved the model metrics by identifying the top 15 miRNAs with the strongest discriminatory value, yielding an AUC of 0.96 ± 0.04, accuracy of 0.896, sensitivity of 0.884, and specificity of 0.903. Our study establishes the potential utility of a non-invasive serum miRNA signature as a supportive tool for early detection of NSCLC while also shedding light on dysregulated miRNAs in NSCLC biology. For enhanced credibility and understanding, further validation in an independent cohort of patients is warranted.

miRNA Studies in Glaucoma: A Comprehensive Review of Current Knowledge and Future Perspectives

Glaucoma, a neurodegenerative disorder that leads to irreversible blindness, remains a challenge because of its complex nature. MicroRNAs (miRNAs) are crucial regulators of gene expression and are associated with glaucoma and other diseases. We aimed to review and discuss the advantages and disadvantages of miRNA-focused molecular studies in glaucoma through discussing their potential as biomarkers for early detection and diagnosis; offering insights into molecular pathways and mechanisms; and discussing their potential utility with respect to personalized medicine, their therapeutic potential, and non-invasive monitoring. Limitations, such as variability, small sample sizes, sample specificity, and limited accessibility to ocular tissues, are also addressed, underscoring the need for robust protocols and collaboration. Reproducibility and validation are crucial to establish the credibility of miRNA research findings, and the integration of bioinformatics tools for miRNA database creation is a valuable component of a comprehensive approach to investigate miRNA aberrations in patients with glaucoma. Overall, miRNA research in glaucoma has provided significant insights into the molecular mechanisms of the disease, offering potential biomarkers, diagnostic tools, and therapeutic targets. However, addressing challenges such as variability and limited tissue accessibility is essential, and further investigations and validation will contribute to a deeper understanding of the functional significance of miRNAs in glaucoma.

miRNA-Seq Tissue Diagnostic Signature: A Novel Model for NSCLC Subtyping

Non-small cell lung cancer (NSCLC) encompasses distinct histopathological subtypes, namely adenocarcinoma (AC) and squamous cell lung carcinoma (SCC), which require precise differentiation for effective treatment strategies. In this study, we present a novel molecular diagnostic model that integrates tissue-specific expression profiles of microRNAs (miRNAs) obtained through next-generation sequencing (NGS) to discriminate between AC and SCC subtypes of NSCLC. This approach offers a more comprehensive and precise molecular characterization compared to conventional methods such as histopathology or immunohistochemistry. Firstly, we identified 31 miRNAs with significant differential expression between AC and SCC cases. Subsequently, we constructed a 17-miRNA signature through rigorous multistep analyses, including LASSO/elastic net regression. The signature includes both upregulated miRNAs (hsa-miR-326, hsa-miR-450a-5p, hsa-miR-1287-5p, hsa-miR-556-5p, hsa-miR-542-3p, hsa-miR-30b-5p, hsa-miR-4728-3p, hsa-miR-450a-1-3p, hsa-miR-375, hsa-miR-147b, hsa-miR-7705, and hsa-miR-653-3p) and downregulated miRNAs (hsa-miR-944, hsa-miR-205-5p, hsa-miR-205-3p, hsa-miR-149-5p, and hsa-miR-6510-3p). To assess the discriminative capability of the 17-miRNA signature, we performed receiver operating characteristic (ROC) curve analysis, which demonstrated an impressive area under the curve (AUC) value of 0.994. Our findings highlight the exceptional diagnostic performance of the miRNA signature as a stratifying biomarker for distinguishing between AC and SCC subtypes in lung cancer. The developed molecular diagnostic model holds promise for providing a more accurate and comprehensive molecular characterization of NSCLC, thereby guiding personalized treatment decisions and improving clinical management and prognosis for patients.

Applied Molecular-Based Quality Control of Biobanked Samples for Multi-Omics Approach

Biobanks are vital for high-throughput translational research, but the rapid development of novel molecular techniques, especially in omics assays, poses challenges to traditional practices and recommendations. In our study, we used biospecimens from oncological patients in Polish clinics and collaborated with the Indivumed Group. For serum/plasma samples, we monitored hemolysis, controlled RNA extraction, assessed cDNA library quality and quantity, and verified NGS raw data. Tissue samples underwent pathologic evaluation to confirm histology and determine tumor content. Molecular quality control measures included evaluating the RNA integrity number, assessing cDNA library quality and quantity, and analyzing NGS raw data. Our study yielded the creation of distinct workflows for conducting preanalytical quality control of serum/plasma and fresh-frozen tissue samples. These workflows offer customization options to suit the capabilities of different biobanking entities. In order to ensure the appropriateness of biospecimens for advanced research applications, we introduced molecular-based quality control methods that align with the demands of high-throughput assays. The novelty of proposed workflows, rooted in innovative molecular techniques, lies in the integration of these QC methods into a comprehensive schema specifically designed for high-throughput research applications.

A Systematic Review of Progress toward Unlocking the Power of Epigenetics in NSCLC: Latest Updates and Perspectives

Epigenetic research has the potential to improve our understanding of the pathogenesis of cancer, specifically non-small-cell lung cancer, and support our efforts to personalize the management of the disease. Epigenetic alterations are expected to have relevance for early detection, diagnosis, outcome prediction, and tumor response to therapy. Additionally, epi-drugs as therapeutic modalities may lead to the recovery of genes delaying tumor growth, thus increasing survival rates, and may be effective against tumors without druggable mutations. Epigenetic changes involve DNA methylation, histone modifications, and the activity of non-coding RNAs, causing gene expression changes and their mutual interactions. This systematic review, based on 110 studies, gives a comprehensive overview of new perspectives on diagnostic (28 studies) and prognostic (25 studies) epigenetic biomarkers, as well as epigenetic treatment options (57 studies) for non-small-cell lung cancer. This paper outlines the crosstalk between epigenetic and genetic factors as well as elucidates clinical contexts including epigenetic treatments, such as dietary supplements and food additives, which serve as anti-carcinogenic compounds and regulators of cellular epigenetics and which are used to reduce toxicity. Furthermore, a future-oriented exploration of epigenetic studies in NSCLC is presented. The findings suggest that additional studies are necessary to comprehend the mechanisms of epigenetic changes and investigate biomarkers, response rates, and tailored combinations of treatments. In the future, epigenetics could have the potential to become an integral part of diagnostics, prognostics, and personalized treatment in NSCLC.

A Signature of 14 Long Non-Coding RNAs (lncRNAs) as a Step towards Precision Diagnosis for NSCLC

LncRNAs have arisen as new players in the world of non-coding RNA. Disrupted expression of these molecules can be tightly linked to the onset, promotion and progression of cancer. The present study estimated the usefulness of 14 lncRNAs (HAGLR, ADAMTS9-AS2, LINC00261, MCM3AP-AS1, TP53TG1, C14orf132, LINC00968, LINC00312, TP73-AS1, LOC344887, LINC00673, SOX2-OT, AFAP1-AS1, LOC730101) for early detection of non-small-cell lung cancer (NSCLC). The total RNA was isolated from paired fresh-frozen cancerous and noncancerous lung tissue from 92 NSCLC patients diagnosed with either adenocarcinoma (LUAD) or lung squamous cell carcinoma (LUSC). The expression level of lncRNAs was evaluated by a quantitative real-time PCR (qPCR). Based on Ct and delta Ct values, logistic regression and gradient boosting decision tree classifiers were built. The latter is a novel, advanced machine learning algorithm with great potential in medical science. The established predictive models showed that a set of 14 lncRNAs accurately discriminates cancerous from noncancerous lung tissues (AUC value of 0.98 ± 0.01) and NSCLC subtypes (AUC value of 0.84 ± 0.09), although the expression of a few molecules was statistically insignificant (SOX2-OT, AFAP1-AS1 and LOC730101 for tumor vs. normal tissue; and TP53TG1, C14orf132, LINC00968 and LOC730101 for LUAD vs. LUSC). However for subtypes discrimination, the simplified logistic regression model based on the four variables (delta Ct AFAP1-AS1, Ct SOX2-OT, Ct LINC00261, and delta Ct LINC00673) had even stronger diagnostic potential than the original one (AUC value of 0.88 ± 0.07). Our results demonstrate that the 14 lncRNA signature can be an auxiliary tool to endorse and complement the histological diagnosis of non-small-cell lung cancer.

Quantitative parameters of gait imbalance in multiple sclerosis patients

Purpose: The purpose is to identify objective quantitative parameters for a more accurate evaluation of gait imbalance and relate it to Body Mass Index and age. Methods: 25 multiple sclerosis (MS) and 30 healthy people (CG) aged between 22 and 66 years old (50.4 ± 9.5) were examined in static and dynamic tasks. The demographic data were as follows: body mass (72.4 ± 18.4 kg in CG vs. 66.8 ± 11.5 kg in MS); body height (1.78 ± 0.15 m in CG vs. 1.70 ± 0.11 m in MS); BMI (24.7 ± 4.5 kg/m2 in CG vs. 23.5 ± 3.0 kg/m2 in MS). First, all individuals remained static for baropodometric, pulse and saturation evaluation. Later on, a 6-minute walk and timed up and go tests were performed and additionally included quantitative measurements by barometry and pulse oximeter. Results: The dynamic condition revealed meaningful differences in the foot surface and hindfoot loading, in addition to foot max. loading between study groups. TUG disclosed significantly different results between groups in time and the number of steps. For MS in statics, the moderate positive correlations between BMI and the right forefoot and right hindfoot, and in MS statics, the correlation of the age vs. maximal left foot loading, forefoot loading and hindfoot loading was observed. In the dynamic, the age and plantar angle of the foot had weak relation. Conclusions: Quantitative parameters defining balance deviations of MS are related to BMI and age in statics and dynamics, therefore should be taken into account during MS imbalance assessment.

Quantitative parameters of gait imbalance in multiple sclerosis patients

PURPOSE

The purpose is to identify objective quantitative parameters for a more accurate evaluation of gait imbalance and relate it to Body Mass Index and age.

METHODS

25 multiple sclerosis (MS) and 30 healthy people (CG) aged between 22 and 66 years old (50.4 ± 9.5) were examined in static and dynamic tasks. The demographic data were as follows: body mass (72.4 ± 18.4 kg in CG vs. 66.8 ± 11.5 kg in MS); body height (1.78 ± 0.15 m in CG vs. 1.70 ± 0.11 m in MS); BMI (24.7 ± 4.5 kg/m2 in CG vs. 23.5 ± 3.0 kg/m2 in MS). First, all individuals remained static for baropodometric, pulse and saturation evaluation. Later on, a 6-minute walk and timed up and go tests were performed and additionally included quantitative measurements by barometry and pulse oximeter.

RESULTS

The dynamic condition revealed meaningful differences in the foot surface and hindfoot loading, in addition to foot max. loading between study groups. TUG disclosed significantly different results between groups in time and the number of steps. For MS in statics, the moderate positive correlations between BMI and the right forefoot and right hindfoot, and in MS statics, the correlation of the age vs. maximal left foot loading, forefoot loading and hindfoot loading was observed. In the dynamic, the age and plantar angle of the foot had weak relation.

CONCLUSIONS

Quantitative parameters defining balance deviations of MS are related to BMI and age in statics and dynamics, therefore should be taken into account during MS imbalance assessment.

Plasmid Mediated mcr-1.1 Colistin-Resistance in Clinical Extraintestinal Escherichia coli Strains Isolated in Poland

Objectives: The growing incidence of multidrug-resistant (MDR) bacteria is an inexorable and fatal challenge in modern medicine. Colistin is a cationic polypeptide considered a “last-resort” antimicrobial for treating infections caused by MDR Gram-negative bacterial pathogens. Plasmid-borne mcr colistin resistance emerged recently, and could potentially lead to essentially untreatable infections, particularly in hospital and veterinary (livestock farming) settings. In this study, we sought to establish the molecular basis of colistin-resistance in six extraintestinal Escherichia coli strains.

Methods: Molecular investigation of colistin-resistance was performed in six extraintestinal E. coli strains isolated from patients hospitalized in Medical University Hospital, Bialystok, Poland. Complete structures of bacterial chromosomes and plasmids were recovered with use of both short- and long-read sequencing technologies and Unicycler hybrid assembly. Moreover, an electrotransformation assay was performed in order to confirm IncX4 plasmid influence on colistin-resistance phenotype in clinical E. coli strains.

Results: Here we report on the emergence of six mcr-1.1-producing extraintestinal E. coli isolates with a number of virulence factors. Mobile pEtN transferase-encoding gene, mcr-1.1, has been proved to be encoded within a type IV secretion system (T4SS)-containing 33.3 kbp IncX4 plasmid pMUB-MCR, next to the PAP2-like membrane-associated lipid phosphatase gene.

Conclusion: IncX4 mcr-containing plasmids are reported as increasingly disseminated among E. coli isolates, making it an “epidemic” plasmid, responsible for (i) dissemination of colistin-resistance determinants between different E. coli clones, and (ii) circulation between environmental, industrial, and clinical settings. Great effort needs to be taken to avoid further dissemination of plasmid-mediated colistin resistance among clinically relevant Gram-negative bacterial pathogens.

Systematic biobanking, novel imaging techniques, and advanced molecular analysis for precise tumor diagnosis and therapy: The Polish MOBIT project

Personalized and precision medicine is gaining recognition due to the limitations by standard diagnosis and treatment; many areas of medicine, from cancer to psychiatry, are moving towards tailored and individualized treatment for patients based on their clinical characteristics and genetic signatures as well as novel imaging techniques. Advances in whole genome sequencing have led to identification of genes involved in a variety of diseases. Moreover, biomarkers indicating severity of disease or susceptibility to treatment are increasingly being characterized. The continued identification of new genes and biomarkers specific to disease subtypes and individual patients is essential and inevitable for translation into personalized medicine, in estimating both, disease risk and response to therapy. Taking into consideration the mostly unsolved necessity of tailored therapy in oncology the innovative project MOBIT (molecular biomarkers for individualized therapy) was designed. The aims of the project are: (i) establishing integrative management of precise tumor diagnosis and therapy including systematic biobanking, novel imaging techniques, and advanced molecular analysis by collecting comprehensive tumor tissues, liquid biopsies (whole blood, serum, plasma), and urine specimens (supernatant; sediment) as well as (ii) developing personalized lung cancer diagnostics based on tumor heterogeneity and integrated genomics, transcriptomics, metabolomics, and radiomics PET/MRI analysis. It will consist of 5 work packages. In this paper the rationale of the Polish MOBIT project as well as its design is presented. (iii) The project is to draw interest in and to invite national and international, private and public, preclinical and clinical initiatives to establish individualized and precise procedures for integrating novel targeted therapies and advanced imaging techniques.

Gene Expression Signature Differentiates Histology But Not Progression Status of Early-Stage NSCLC

Advances in molecular analyses based on high-throughput technologies can contribute to a more accurate classification of non-small cell lung cancer (NSCLC), as well as a better prediction of both the disease course and the efficacy of targeted therapies. Here we set out to analyze whether global gene expression profiling performed in a group of early-stage NSCLC patients can contribute to classifying tumor subtypes and predicting the disease prognosis. Gene expression profiling was performed with the use of the microarray technology in a training set of 108 NSCLC samples. Subsequently, the recorded findings were validated further in an independent cohort of 44 samples. We demonstrated that the specific gene patterns differed significantly between lung adenocarcinoma (AC) and squamous cell lung carcinoma (SCC) samples. Furthermore, we developed and validated a novel 53-gene signature distinguishing SCC from AC with 93% accuracy. Evaluation of the classifier performance in the validation set showed that our predictor classified the AC patients with 100% sensitivity and 88% specificity. We revealed that gene expression patterns observed in the early stages of NSCLC may help elucidate the histological distinctions of tumors through identification of different gene-mediated biological processes involved in the pathogenesis of histologically distinct tumors. However, we showed here that the gene expression profiles did not provide additional value in predicting the progression status of the early-stage NSCLC. Nevertheless, the gene expression signature analysis enabled us to perform a reliable subclassification of NSCLC tumors, and it can therefore become a useful diagnostic tool for a more accurate selection of patients for targeted therapies.

Are anti-Müllerian hormone and its receptor polymorphism associated with the hormonal condition of undescended testes?

PURPOSE

Numerous genetic and endocrine factors are involved in the process of testicular descent, but only a few genetic causes have been reported in human. The aim of this study was to investigate the density and distribution of single nucleotide polymorphisms (SNPs) anti-Müllerian hormone (AMH) and AMHRII receptors in cryptorchid patients and determine potential hormone imbalance connected with undescended testes by assessing the levels of AMH, Insulin-like factor 3 (INSL3) and inhibin B.

MATERIALS AND METHODS

The serum hormone levels (AMH, INSL3 and inhibin B) were compared in the two groups - cryptorchidism (n=105) and control group (n=58). The frequency of AMHRII -482 A>G, AMHRII IVS 10+77 A>G, AMHRII IVS 5-6 C>T, and AMH Ile49Ser polymorphisms among cryptorchid boys were compared with the control group.

RESULTS

None of the hormones levels were different between the cryptorchid and the control groups. All cases of IVS 5-6 C>T homozygote and heterozygote mutation were accompanied by an IVS 10+77 A>G and 482 A>G homozygote and heterozygote mutation. Interestingly, in most cases of all four polymorphisms, homozygote recessive genotype was associated with cases of cryptorchidism. However, the groups of patients were too small to draw definite conclusions.

CONCLUSION

The AMHRII -482 A>G, AMHRII IVS 10+77 A>G, AMHRII IVS 5-6 C>T and AMH Ile49Ser genotypes should be determined in a much larger group of boys with cryptorchidism.

Prognostic value of vascular endothelial growth factor-C and podoplanin mRNA expression in esophageal cancer

Vascular endothelial growth factor-C (VEGF-C), VEGF-D, VEGF receptor-3 (VEGFR-3) and podoplanin (PDPN) are involved in the spread of cancer. The current study evaluated VEGF-C, VEGF-D, VEGFR-3 and PDPN mRNA expression levels in 84 esophageal cancer samples from patients who had undergone surgery according to reverse transcription-quantitative polymerase chain reaction, and correlated the results with the clinicopathological features. The effects on lymph node metastasis and survival were identified by performing univariate and multivariate analyses. VEGF-C, PDPN, VEGF-D and VEGFR-3 were overexpressed in 52.4, 52.4, 32.1 and 51.2% of esophageal cancer samples, respectively. Furthermore, the expression of VEGF-C and PDPN was significantly correlated with lymph node metastasis, depth of tumor invasion and tumor stage (P<0.05). Logistic regression analysis identified tumor size (P=0.001), depth of invasion (P=0.002) and PDPN mRNA expression (P=0.022) as significant multivariable predictors of regional lymph node metastasis. Upon univariate survival analysis, the depth of tumor invasion, lymph node metastasis, histological grade, tumor stage, tumor size, residual tumor, and VEGF-C and PDPN mRNA expression were identified to be significant independent prognostic factors for overall survival (OS) time. Additionally, multivariate analysis identified tumor size (P=0.049), residual tumor (P<0.001) and PDPN mRNA expression (P=0.02) as independent factors for poor OS time. Thus, it was concluded that PDPN mRNA expression may serve as predictor for regional lymph node metastasis, and that VEGF-C and PDPN may be prognostic factors in patients with resected esophageal cancer.

Validation for histology-driven diagnosis in non-small cell lung cancer using hsa-miR-205 and hsa-miR-21 expression by two different normalization strategies

Targeted therapy of non-small cell lung cancer (NSCLC) demands a more accurate tumor classification that is crucial for patient selection in personalized treatment. MicroRNAs constitute a promising class of biomarkers and a helpful tool for the distinction between lung adenocarcinoma (AC) and squamous cell lung carcinoma (SCC). The aim of this study was to evaluate the impact of two different normalization strategies, using U6 snRNA and hsa-miR-103 as reference genes, on hsa-miR-205 and hsa-miR-21 expression levels, in terms of the classification of subtypes of NSCLC. By means of a quantitative real-time polymerase chain reaction (qRT-PCR) microRNA expression levels were evaluated in a classification set of 98 surgically resected NSCLC fresh-frozen samples, and validated findings in an independent set of 42 NSCLC samples. The microRNA expression levels were exploited to develop a diagnostic test using two data normalization strategies. The performance of microRNA profiling in different normalization methods was compared. We revealed the microRNA-based qRT-PCR tests to be appropriate measures for distinguishing between AC and SCC (the concordance of histologic diagnoses and molecular methods greater than 88%). Performance evaluation of microRNA tests, based on the two normalization strategies, showed that the procedure using hsa-miR-103 as reference target has a slight advantage (sensitivity 83.33 and 100% in classification and validation set, respectively) compared to U6 snRNA. Molecular tests based on microRNA expression allow a reliable classification of subtypes for NSCLC and can constitute a useful diagnostic strategy in patient selection for targeted therapy.

Detection of DNA methylation in eucaryotic cells

The methods of molecular biology allow for analyzing the methylation pattern in the whole genome and in particular genes. We differentiate methylated sequences from unmethylated ones by means of cutting the genomic template with methylation-sensitive restriction enzymes or by sodium bisulfite DNA modification. Chemical modification precedes most quantitative and qualitative PCR techniques: MS-PCR, MS-nested PCR, Real-Time PCR, QAMA, HeavyMethyl, MSHRM. Restriction enzymes, on the other hand, may be used together with PCR or hybridisation methods (Southern blot and microarrays). PCRs are conducted with primers specific for methylated and unmethylated sequences and sometimes, similarly to hybridisation techniques, with specifically labeled probes or dyes intercalating to double-stranded nucleic acids. The most advanced methylation detection techniques (MALDI-TOF MS and HPLC) significantly reduce the amount of biological material used for tests, but they require specialist equipment.

Serum soluble Fas ligand (sFasL) in patients with primary squamous cell carcinoma of the esophagus

Esophageal carcinomas have been shown to express Fas ligand (FasL) and down-regulate Fas to escape from host immune surveillance. Circulating soluble FasL (sFasL) has been suggested to provide protection from Fas-mediated apoptosis. The aim of this study was to assess serum sFasL levels in esophageal cancer. The pretreatment levels of sFasL in the serum of 100 patients with esophageal squamous cell cancer and 41 healthy volunteers were determined by ELISA. Probability of survival was calculated according to the method of Kaplan-Meier. The prognostic influence of high and low level of sFasL was analyzed with the log-rank test. The mean serum level of sFasL in patients with esophageal cancer was significantly higher than that in healthy donors (1.567+/-1.786 vs 0.261+/-0.435, p<0.0001). The levels of serum sFasL were significantly higher in advanced stages (II vs IV p<0.034; III vs IV p<0.041; except II vs III p=0.281), patients with lymph node (N0 vs N1 p<0.0389) or distant (M0 vs. M1 p<0.0388) metastases and significantly lower in patients with well differentiated tumors (G1 vs G2 p<0.0272). The serum levels of soluble FasL were not related to gender, age, tumor size, T-stage, tobacco smoking and history of chronic alcohol intake. The survival difference between pretreatment high and low level of sFasL in surgery and chemio- and/or radiotherapy group was not statistically significant (p=0.525; p=0.840). Our results indicate that elevated serum sFasL levels might be associated with a disease progression in patients with esophageal squamous cell carcinoma.

DNA methylation in states of cell physiology and pathology

DNA methylation is one of epigenetic mechanisms regulating gene expression. The methylation pattern is determined during embryogenesis and passed over to differentiating cells and tissues. In a normal cell, a significant degree of methylation is characteristic for extragenic DNA (cytosine within the CG dinucleotide) while CpG islands located in gene promoters are unmethylated, except for inactive genes of the X chromosome and the genes subjected to genomic imprinting. The changes in the methylation pattern, which may appear as the organism age and in early stages of cancerogenesis, may lead to the silencing of over ninety endogenic genes. It has been found, that these disorders consist not only of the methylation of CpG islands, which are normally unmethylated, but also of the methylation of other dinucleotides, e.g. CpA. Such methylation has been observed in non-small cell lung cancer, in three regions of the exon 5 of the p53 gene (so-called "non-CpG" methylation). The knowledge of a normal methylation process and its aberrations appeared to be useful while searching for new markers enabling an early detection of cancer. With the application of the Real-Time PCR technique (using primers for methylated and unmethylated sequences) five new genes which are potential biomarkers of lung cancer have been presented.

Attempts to detect Helicobacter pylori in atherosclerotic plaques

Cardiovascular and cerebrovascular diseases are regarded to be the main causes of mortality in developed countries, atherosclerosis being at their pathological base. During the recent years, attention was paid to the role of bacterial infections, including Helicobacter pylori, in the process of atherogenesis and coronary heart disease development. The aim of the study was an evaluation of H. pylori presence--by means of PCR technique--in atherosclerotic changes, obtained by endarterectomy, performed during coronary artery bypass grafting (CABG). In the analysed group of patients, the following risk factors were found: hyperlipidaemia, smoking, hypertension, obesity, diabetes mellitus, cardiac infarction. No DNA of the bacteria was traced in any of the patients.

Morphological evaluation of the lungs in rats with experimentally induced renal failure

The study aimed at morphological evaluation of changes in the lungs of rats during experimentally induced uremia. The studies were performed in three (3) groups of rats: C--a control group (15 animals), SO--15 rats, submitted to sham operation, U--an uremic group--21 rats with experimental renal failure. After 1, 2 and 4 weeks from the surgery, the collected lungs were fixed in Bouin's fluid and in 2.5% purified glutaraldehyde for electron microscopy. Paraffin specimens were cut into 5 microm slices and stained by H+E, by Azan's method and with silver, according to Grimelius. Ultra thin sections contrasted with uranyl acetate and lead citrate. Blood serum urea and creatinine levels were determined. In the uremic rats, increased concentrations of serum creatinine and urea were observed. Chronic renal failure affected the progress and the degree of development of the changes in the lungs, the final effect of which was fibrosis. In microscopic pictures of the lungs from the uremic rats, numerous changes were observed, characteristic for chronic oedematous conditions of different intensification.

Pulmonary neuroendocrine cells in physiology and pathology

Pulmonary neuroendocrine cells are scant and widespread within the pulmonary epithelium. The function they play is not fully known, more studies are needed to clearly define it. They have been implicated however, as either the culprit or victim of many pulmonary diseases. That is the reason, why so many scientists take interest in the pulmonary neuroendocrine system. This paper reviews current information regarding pulmonary neuroendocrine cells, their origin, morphology, ontogeny, role, neuroendocrine cell markers, dysplasia and hyperplasia of pulmonary neuroendocrine cells in various conditions, diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, typical carcinoid, atypical carcinoid, small-cell lung carcinoma, large-cell neuroendocrine carcinoma and the unusual spectrum of pulmonary neuroendocrine tumours.

Detection of human papillomavirus in papillomas of oral cavity

The oral cavity is exposed to many harmful factors among others: tobacco, alcohol and viral infection e.g. human papillomaviruses (HPV). HPV belongs to a family of tumorigenic viruses and induces cutaneous and mucosal proliferations of epithelial cells. The aim of our study was to estimate the frequency of HPV occurrence in papillomas of oral cavity in the Podlasie region. The study included 38 papillomas of oral cavity. HPV was found in 14 cases (36.8%). High risk HPV was present in 12 papillomas, while low risk HPV was detected in 2 papillomas.