Molecular Classification of Medullobastomas by Whole Genome Expression Profiling.

BACKGROUND: Medulloblastoma (MB) is the most common malignant tumour of the central nervous system in children. MB is considered to be high risk tumour propensity to metastasize. In the Czech Republic, approximately 10-12 children are affected annually by this tumour. Recent progress in molecular diagnostics helps to refine the diagnosis and estimate clinical prognosis of the disease. Currently, MBs are subclassified into WNT-activated, SHH-activated, group 3, and 4 based on molecular pathways that drive their tumorigenesis. Each subtype differs in its histopathology, clinical features, genomic changes and gene expressions. The aim of our study is to classify patients MBs into four basic molecular groups and compare our results with published data. MATERIAL AND METHODS: In our study we analysed expression profiles using Affymetrix GeneChip Human Gene 1.0. ST Array (Thermo Fisher Scientific, MA, USA). As input material RNA extracted from the fresh frozen tissue was used. Molecular classification based on the method established by P. Northcott in 2011 was performed. RESULTS: From April 2015 to February 2019, 21 patients with MBs were included in our study. Median age of the patients at the time of diagnosis was 6 years, 14 boys and 7 girls were enrolled. Gene expression profiling and molecular classification of MBs was performed. Based on this methodology, we found the most frequently represented subgroup of MB was group 4 (9 patients, 43%), followed by group 3 (5 patients, 24%), SHH-activated MB (4 patients, 19%) and the least represented subgroup was WNT-activated MB (3 patients, 14%). Results of molecular subgroup classification of MBs were successfully correlated with histopathological findings and other molecular-genetic examinations. CONCLUSION: Molecular classification of MBs has been established in our institution allowing better understanding of this heterogeneous disease and helping clinicians in therapeutic planning in affected patients. This work was supported by the Czech Ministry of Health grant No. 16-33209A. All rights reserved.  he authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 1. 3. 2019 Accepted: 4. 3. 2019.

[Urinary MicroRNAs as Potential Biomarkers of Bladder Cancer]. / Mocové mikroRNA jako potenciální biomarkery karcinomu mocového mechýre.

BACKGROUND: Currently, there are no urinary-based tumour markers with sufficient sensitivity and specificity to replace cystoscopy in the detection of bladder cancer (BCA). Urinary microRNAs are emerging as clinically useful class of biomarkers for early and non-invasive detection of urologic malignancies. PATIENTS AND METHODS: In this study, 155 patients with BCA and 83 healthy controls were enrolled. Expression profiles of urinary miRNAs were obtained using Affymetrix miRNA microarrays and candidate miRNAs further validated in independent cohort using specific TaqMan assays and quantitative real-time polymerase chain reaction method. RESULTS: Whole-genome profiling identified miRNA signature with significantly different concentrations in urine of BCA compared to controls (p < 0.01). In the independent validation phase of the study, three miRNAs were confirmed to have significantly higher levels in urine of patients with BCA in comparison with control groups (p < 0.0001). In addition, we observed significant decrease in two miRNAs (p < 0.01) concentrations in the urinary samples collected 3 months after surgery compared to pre-operative samples. CONCLUSION: We identified and validated miRNAs to have significantly higher concentrations in urine of patients with BCA in comparison with controls. Our data have shown that urinary miRNAs could serve as sensitive and specific biomarkers enabling non-invasive detection of BCA.Key words: urinary microRNAs - biomarkers - bladder cancer The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. This study was supported by Ministry of Health of the Czech Republic, grant No. 15-31071A. All rights reserved.Submitted: 19. 3. 2018Accepted: 20. 3. 2018.