BACKGROUND: Presensitized patients with circulating donor-specific antibodies (DSAs) before transplantation are at risk for antibody-mediated rejection (AMR). Peritransplant desensitization mitigates but does not eliminate the alloimmune response. We examined the possibility that subthreshold AMR activity undetected by histology could be operating in some early biopsies. METHODS: Transcriptome of kidney allograft biopsies performed within the first month in presensitized patients (DSA+) who had received desensitization and did not develop active/probable AMR by histology (R-) was compared with biopsies showing active/probable AMR (R+/DSA+). As negative controls, biopsies without rejection by histology in patients without DSA at transplantation were used (R-/DSA-). RNA sequencing from biopsies selected from the biobank was used in cohort 1 (n = 32) and microarray, including the molecular microscope (Molecular Microscope Diagnostic System [MMDx]) algorithm, in recent cohort 2 (n = 30). RESULTS: The transcriptome of R-/DSA+ was similar to R+/DSA+ as these groups differed in 14 transcripts only. Contrarily, large differences were found between both DSA+ groups and negative controls. Fast gene set enrichment analyses showed upregulation of the immune system in both DSA+ groups (gene ontology terms: adaptive immune response, humoral immune response, antigen receptor-mediated signaling, and B-cell receptor signaling or complement activation) when compared with negative controls. MMDx assessment in cohort 2 classified 50% of R-/DSA+ samples as AMR and found no differences in AMR molecular scores between R+ and R- DSA+ groups. In imlifidase desensitization, MMDx series showed a gradual increase in AMR scores over time. CONCLUSIONS: Presensitized kidney transplant recipients exhibited frequent molecular calls of AMR in biopsy-based transcript diagnostics despite desensitization therapy and negative histology.

• Publikační typ
• časopisecké články MeSH

Aim: Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Methods: Blood samples from female volunteers were processed before and after inhalation exposure. Transcriptomic mRNA and miRNA expression changes were analyzed. Results: We detected large interindividual variability, 90 significantly deregulated mRNAs, and 4 miRNAs when samples of participants before and after dental nanocomposite grinding were compared. Conclusion: The results suggest that inhaled dental NPs may present an occupational hazard to human health, as indicated by the changes in the processes related to oxidative stress, synthesis of eicosanoids, and cell division.

• MeSH
• dospělí MeSH
• inhalační expozice * škodlivé účinky   MeSH
• lidé MeSH
• messenger RNA genetika   MeSH
• mikro RNA * genetika   MeSH
• nanočástice chemie   MeSH
• nanokompozity * chemie   MeSH
• oxidační stres účinky léků   MeSH
• pracovní expozice škodlivé účinky   MeSH
• transkriptom * účinky léků   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We analyzed gene expression in THP-1 cells exposed to metal-based nanomaterials (NMs) [TiO2 (NM-100), ZnO (NM-110), SiO2 (NM-200), Ag (NM-300 K)]. A functional enrichment analysis of the significant differentially expressed genes (DEGs) identified the key modulated biological processes and pathways. DEGs were used to construct protein-protein interaction networks. NM-110 and NM-300 K induced changes in the expression of genes involved in oxidative and genotoxic stress, immune response, alterations of cell cycle, detoxification of metal ions and regulation of redox-sensitive pathways. Both NMs shared a number of highly connected protein nodes (hubs) including CXCL8, ATF3, HMOX1, and IL1B. NM-200 induced limited transcriptional changes, mostly related to the immune response; however, several hubs (CXCL8, ATF3) were identical with NM-110 and NM-300 K. No effects of NM-100 were observed. Overall, soluble nanomaterials NM-110 and NM-300 K exerted a wide variety of toxic effects, while insoluble NM-200 induced immunotoxicity; NM-100 caused no detectable changes on the gene expression level.

• MeSH
• hemoxygenasa-1 MeSH
• interleukin-8 metabolismus   genetika   MeSH
• kovové nanočástice toxicita   MeSH
• lidé MeSH
• mapy interakcí proteinů * účinky léků   MeSH
• nanostruktury toxicita   MeSH
• oxid křemičitý toxicita   MeSH
• oxid zinečnatý toxicita   chemie   MeSH
• stříbro * toxicita   MeSH
• THP-1 buňky MeSH
• titan * toxicita   MeSH
• transkripční faktor ATF3 genetika   metabolismus   MeSH
• transkriptom účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Operational tolerance (OT) has been observed in patients who stopped their immunosuppression for more than a year and no destructive alloimmune response was noticed. B cell-related immunophenotypic and transcriptomic signatures were identified so far among OT kidney transplant recipients. The aim of this project is to evaluate peripheral blood transcriptomic profile using RNA-sequencing in newly identified european cohort of OT patients and compared it with well-defined controls. Moreover, we plan to validate protective role of several transcripts associated with OT in a large patient population. Next, we plan to evaluate B cell immunophenotypes in patients with long-term graft function and with chronic rejection. The identification and validation of biomarkers of operational tolerance / immune quiescence may thus allow construct bedside clinical tests enable to guide immunosuppression.

Operační tolerance (OT) byla pozorována u nemocných, kteří přestali užívat imunosupresi po více jak 1 rok a nebyla u nich zaznamenána žádná destruktivní imunitní odpověď. Imunofenotypy B lymfocytů a transcripty spojené s B lymfocyty byly identifikovány mezi nemocnými s OT. Cílem projektu je vyšetřit transkriptomický profil periferní krve nově identifikovaných evropských pacientů s OT ve srovnání s dobře definovanými kontrolními skupinami. Dále plánujeme validovat prognostickou roli několika periferních transkriptů spojených s OT na velké kohortě nemocných po transplantaci ledviny léčených imunosupresí. Dále zamýšlíme ověřit protektivní roli fenotypů B lymfocytů u nemocných s dlouhodobě stabilní funkcí štěpu ve srovnání s nemocnými s biopticky potvrzenou chronickou rejekcí. Identifikace a validace biomarkerů OT / imunitní neodpovídavosti může umožnit konstrukci jednoduchých klinických testů k řízení imunosupresivní terapie.

• Klíčová slova
• imunosuprese, B lymfocyty, immunosuppression, kidney transplantation, transplantace ledvin, operační tolerance, operational tolerance, B-cells,

• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Mutations in the splicing factor 3b subunit 1 (SF3B1) gene are frequent in myelodysplastic neoplasms (MDS). Because the splicing process is involved in the production of circular RNAs (circRNAs), we investigated the impact of SF3B1 mutations on circRNA processing. Using RNA sequencing, we measured circRNA expression in CD34+ bone marrow MDS cells. We defined circRNAs deregulated in a heterogeneous group of MDS patients and described increased circRNA formation in higher-risk MDS. We showed that the presence of SF3B1 mutations did not affect the global production of circRNAs; however, deregulation of specific circRNAs was observed. Particularly, we demonstrated that strong upregulation of circRNAs processed from the zinc finger E-box binding homeobox 1 (ZEB1) transcription factor; this upregulation was exclusive to SF3B1-mutated patients and was not observed in those with mutations in other splicing factors or other recurrently mutated genes, or with other clinical variables. Furthermore, we focused on the most upregulated ZEB1-circRNA, hsa_circ_0000228, and, by its knockdown, we demonstrated that its expression is related to mitochondrial activity. Using microRNA analyses, we proposed miR-1248 as a direct target of hsa_circ_0000228. To conclude, we demonstrated that mutated SF3B1 leads to deregulation of ZEB1-circRNAs, potentially contributing to the defects in mitochondrial metabolism observed in SF3B1-mutated MDS.

• MeSH
• akutní myeloidní leukemie * MeSH
• fosfoproteiny genetika   MeSH
• kruhová RNA genetika   MeSH
• lidé MeSH
• mutace genetika   MeSH
• myelodysplastické syndromy * genetika   MeSH
• sestřihové faktory genetika   MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Recent research has already shown that circular RNAs (circRNAs) are functional in gene expression regulation and potentially related to diseases. Due to their stability, circRNAs can also be used as biomarkers for diagnosis. However, the function of most circRNAs remains unknown, and it is expensive and time-consuming to discover it through biological experiments. In this paper, we predict circRNA annotations from the knowledge of their interaction with miRNAs and subsequent miRNA-mRNA interactions. First, we construct an interaction network for a target circRNA and secondly spread the information from the network nodes with the known function to the root circRNA node. This idea itself is not new; our main contribution lies in proposing an efficient and exact deterministic procedure based on the principle of probability-generating functions to calculate the p-value of association test between a circRNA and an annotation term. We show that our publicly available algorithm is both more effective and efficient than the commonly used Monte-Carlo sampling approach that may suffer from difficult quantification of sampling convergence and subsequent sampling inefficiency. We experimentally demonstrate that the new approach is two orders of magnitude faster than the Monte-Carlo sampling, which makes summary annotation of large circRNA files feasible; this includes their reannotation after periodical interaction network updates, for example. We provide a summary annotation of a current circRNA database as one of our outputs. The proposed algorithm could be generalized towards other types of RNA in way that is straightforward.

• MeSH
• biologické markery MeSH
• genové regulační sítě MeSH
• kruhová RNA * MeSH
• messenger RNA genetika   metabolismus   MeSH
• mikro RNA * genetika   metabolismus   MeSH
• pravděpodobnost MeSH
• stanovení celkové genové exprese metody   MeSH
• Publikační typ
• časopisecké články MeSH

Long non-coding RNAs (lncRNAs) regulate hematopoietic lineage differentiation at almost every stage and their abnormal expression may contribute to various hematopoietic disorders. They may become useful diagnostic and prognostic markers contributing to detection of the MDS progression and increase of the patients' survival, and even potential therapeutic targets in future. In the proposed project, genome-wide screening of lncRNA levels in MDS patients will be employed to compare expression profiles between various risk groups of patients with the aim to find lncRNAs with significantly different levels and relevance to MDS diagnostics. Because the knowledge about individual lncRNAs is often limited to the simple transcript annotation, the causes, roles and consequences of deregulated lncRNAs in the pathogenesis of MDS will be studied by experimental and computational approaches.

Dlouhé nekódující RNA (lncRNA) regulují diferenciaci krevních buněk na mnoha úrovních a jejich abnormální exprese tak přispívá k různým hematopoetickým onemocněním. LncRNA se mohou ukázat jako významné diagnostické a prognostické markery přispívajícími k včasné detekci progrese MDS a zlepšení přežití pacientů, či se mohou v budoucnu stát potenciálními terapeutickými cíli. V navrhovaném projektu budou prováděna celogenomová vyšetření hladin lncRNAs u pacientů s MDS a srovnání expresních profilů mezi různými skupinami pacientů s cílem najít lncRNAs s výrazně odlišnými hladinami a potenciálním využitím v diagnostice MDS. Protože znalosti o jednotlivých lncRNA jsou často limitovány na pouhou anotaci transkriptu, budou v rámci projektu dále studovány příčiny, role a důsledky deregulovaných lncRNA pro patogenezi MDS pomocí experimentálních a výpočetních přístupů.

• Klíčová slova
• biomarkery, biomarkers, myelodysplastický syndrom, dlouhé nekódující RNA, exprese, expression, integrace dat, data integration, myelodysplastic syndromes, long non-coding RNA,

• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Patients with lower-risk myelodysplastic syndromes (LR-MDS) have a generally favorable prognosis; however, a small proportion of cases progress rapidly. This study aimed to define molecular biomarkers predictive of LR-MDS progression and to uncover cellular pathways contributing to malignant transformation. The mutational landscape was analyzed in 214 LR-MDS patients, and at least one mutation was detected in 137 patients (64%). Mutated RUNX1 was identified as the main molecular predictor of rapid progression by statistics and machine learning. To study the effect of mutated RUNX1 on pathway regulation, the expression profiles of CD34 + cells from LR-MDS patients with RUNX1 mutations were compared to those from patients without RUNX1 mutations. The data suggest that RUNX1-unmutated LR-MDS cells are protected by DNA damage response (DDR) mechanisms and cellular senescence as an antitumor cellular barrier, while RUNX1 mutations may be one of the triggers of malignant transformation. Dysregulated DDR and cellular senescence were also observed at the functional level by detecting γH2AX expression and β-galactosidase activity. Notably, the expression profiles of RUNX1-mutated LR-MDS resembled those of higher-risk MDS at diagnosis. This study demonstrates that incorporating molecular data improves LR-MDS risk stratification and that mutated RUNX1 is associated with a suppressed defense against LR-MDS progression.

• MeSH
• akutní myeloidní leukemie * genetika   MeSH
• lidé MeSH
• mutace MeSH
• myelodysplastické syndromy * patologie   MeSH
• nádorová transformace buněk genetika   metabolismus   MeSH
• prognóza MeSH
• protein PEBP2A2 genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND/AIM: Prediction of response to azacitidine (AZA) treatment is an important challenge in hematooncology. In addition to protein coding genes (PCGs), AZA efficiency is influenced by various noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs), circular RNAs (circRNAs), and transposable elements (TEs). MATERIALS AND METHODS: RNA sequencing was performed in patients with myelodysplastic syndromes or acute myeloid leukemia before AZA treatment to assess contribution of ncRNAs to AZA mechanisms and propose novel disease prediction biomarkers. RESULTS: Our analyses showed that lncRNAs had the strongest predictive potential. The combined set of the best predictors included 14 lncRNAs, and only four PCGs, one circRNA, and no TEs. Epigenetic regulation and recombinational repair were suggested as crucial for AZA response, and network modeling defined three deregulated lncRNAs (CTC-482H14.5, RP11-419K12.2, and RP11-736I24.4) associated with these processes. CONCLUSION: The expression of various ncRNAs can influence the effect of AZA and new ncRNA-based predictive biomarkers can be defined.

• MeSH
• akutní myeloidní leukemie * farmakoterapie   genetika   MeSH
• azacytidin farmakologie   terapeutické užití   MeSH
• epigeneze genetická MeSH
• lidé MeSH
• myelodysplastické syndromy * farmakoterapie   genetika   MeSH
• RNA dlouhá nekódující * genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Ubiquitin ligases (Ub-ligases) are essential intracellular enzymes responsible for the regulation of proteome homeostasis, signaling pathway crosstalk, cell differentiation and stress responses. Individual Ub-ligases exhibit their unique functions based on the nature of their substrates. They create a complex regulatory network with alternative and feedback pathways to maintain cell homeostasis, being thus important players in many physiological and pathological conditions. However, the functional classification of Ub-ligases needs to be revised and extended. METHODS: In the current study, we used a novel semantic biclustering technique for expression profiling of Ub-ligases and ubiquitination-related genes in the murine gastrointestinal tract (GIT). We accommodated a general framework of the algorithm for finding tissue-specific gene expression clusters in GIT. In order to test identified clusters in a biological system, we used a model of epithelial regeneration. For this purpose, a dextran sulfate sodium (DSS) mouse model, following with in situ hybridization, was used to expose genes with possible compensatory features. To determine cell-type specific distribution of Ub-ligases and ubiquitination-related genes, principal component analysis (PCA) and Uniform Manifold Approximation and Projection technique (UMAP) were used to analyze the Tabula Muris scRNA-seq data of murine colon followed by comparison with our clustering results. RESULTS: Our established clustering protocol, that incorporates the semantic biclustering algorithm, demonstrated the potential to reveal interesting expression patterns. In this manner, we statistically defined gene clusters consisting of the same genes involved in distinct regulatory pathways vs distinct genes playing roles in functionally similar signaling pathways. This allowed us to uncover the potentially redundant features of GIT-specific Ub-ligases and ubiquitination-related genes. Testing the statistically obtained results on the mouse model showed that genes clustered to the same ontology group simultaneously alter their expression pattern after induced epithelial damage, illustrating their complementary role during tissue regeneration. CONCLUSIONS: An optimized semantic clustering protocol demonstrates the potential to reveal a readable and unique pattern in the expression profiling of GIT-specific Ub-ligases, exposing ontologically relevant gene clusters with potentially redundant features. This extends our knowledge of ontological relationships among Ub-ligases and ubiquitination-related genes, providing an alternative and more functional gene classification. In a similar way, semantic cluster analysis could be used for studding of other enzyme families, tissues and systems.

• MeSH
• gastrointestinální trakt metabolismus   MeSH
• lidé MeSH
• myši MeSH
• sémantika * MeSH
• shluková analýza MeSH
• ubikvitin genetika   metabolismus   MeSH
• ubikvitinligasy * genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH