TRIAL REGISTRATION: GA trial is registered under EudraCT#: 2013-001639-38.

• MeSH
• antimetabolity antitumorózní terapeutické užití   MeSH
• azacytidin * terapeutické užití   MeSH
• faktor stimulující kolonie granulocytů MeSH
• lidé MeSH
• myelodysplastické syndromy * farmakoterapie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• dopisy MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH

The mechanisms by which myelodysplastic syndrome (MDS) cells resist the effects of hypomethylating agents (HMA) are currently the subject of intensive research. A better understanding of mechanisms by which the MDS cell becomes to tolerate HMA and progresses to acute myeloid leukemia (AML) requires the development of new cellular models. From MDS/AML cell lines we developed a model of 5-azacytidine (AZA) resistance whose stability was validated by a transplantation approach into immunocompromised mice. When investigating mRNA expression and DNA variants of the AZA resistant phenotype we observed deregulation of several cancer-related pathways including the phosphatidylinosito-3 kinase signaling. We have further shown that these pathways can be modulated by specific inhibitors that, while blocking the proliferation of AZA resistant cells, are unable to increase their sensitivity to AZA. Our data reveal a set of molecular mechanisms that can be targeted to expand therapeutic options during progression on AZA therapy.

• MeSH
• anotace sekvence MeSH
• azacytidin farmakologie   MeSH
• biologické modely * MeSH
• chemorezistence * účinky léků   genetika   MeSH
• DNA nádorová genetika   MeSH
• fosfatidylinositol-3-kinasy metabolismus   MeSH
• myši SCID MeSH
• myši MeSH
• protoonkogenní proteiny c-akt metabolismus   MeSH
• reprodukovatelnost výsledků MeSH
• signální transdukce účinky léků   MeSH
• transkriptom genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Hereditary haemorrhagic telangiectasia (HHT) exhibits considerable phenotypic heterogeneity. Therefore, precise mutation screening and evaluation of patient risk must be determined in every HHT family. We present an HHT-2 case with an initial life-threatening bleeding episode that led to identification of a relatively large HHT family. Exome sequencing of the family members determined HHT-associated ACVRL1C1120T variant resulting in Arg374Trp substitution at the Ser/Thr-kinase domain region. The affected members display typical epistaxis symptomatology from early childhood resulting in sideropoenia. In addition, the HHT patients also displayed dermatology findings such as facial teleangiectasias and trunk/limb white spots representing post-inflammatory hypopigmentation. Interestingly, co-segregating with modifying cytochrome P450 (CYP2C) variant in the HHT patients led to NSAID intolerance marked by increased frequency of bleeding episodes. No arterial-venous malformation of the visceral organs and brain or association with cancer were observed. The heterogeneity of clinical presentation and the role of other variants support the need of regular patient monitoring and development of a nation-wide patient registry.

• MeSH
• cytochrom P450 CYP2C9 genetika   MeSH
• epistaxe MeSH
• hereditární hemoragická teleangiektazie genetika   MeSH
• lidé MeSH
• nádory kůže genetika   MeSH
• registrace MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

• MeSH
• azacytidin * aplikace a dávkování   MeSH
• faktor stimulující kolonie granulocytů terapeutické užití   MeSH
• lidé MeSH
• myelodysplastické syndromy * farmakoterapie   MeSH
• statistika jako téma MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• randomizované kontrolované studie MeSH

Azacitidine (AZA) for higher risk MDS patients is a standard therapy with limited durability. To monitor mutation dynamics during AZA therapy we utilized massive parallel sequencing of 54 genes previously associated with MDS/AML pathogenesis. Serial sampling before and during AZA therapy of 38 patients (reaching median overall survival 24 months (Mo) with 60% clinical responses) identified 116 somatic pathogenic variants with allele frequency (VAF) exceeding 5%. High accuracy of data was achieved via duplicate libraries from myeloid cells and T-cell controls. We observed that nearly half of the variants were stable while other variants were highly dynamic. Patients with marked decrease of allelic burden upon AZA therapy achieved clinical responses. In contrast, early-progressing patients on AZA displayed minimal changes of the mutation pattern. We modeled the VAF dynamics on AZA and utilized a joint model for the overall survival and response duration. While the presence of certain variants associated with clinical outcomes, such as the mutations ofCDKN2Awere adverse predictors whileKDM6Amutations yield lower risk of dying, the data also indicate that allelic burden volatility represents additional important prognostic variable. In addition, preceding 5q- syndrome represents strong positive predictor of longer overall survival and response duration in high risk MDS patients treated with AZA. In conclusion, variants dynamics detected via serial sampling represents another parameter to consider when evaluating AZA efficacy and predicting outcome.

• Publikační typ
• časopisecké články MeSH

Primary cutaneous T-cell lymphomas (CTCL) affect the skin and tend to transform and spread. CTCL involves primarily the Mycosis fungoides (MF) and more aggressive Sezary syndrome (SS). Oncogenic microRNAs (miRs) are stable epigenetic inhibitors often deregulated in the tumour and detectable as biomarkers in non-cellular fractions of peripheral blood. The tumour-specific expression of miR-155, miR-203, and miR-205 was shown to correctly diagnose CTCL. We herein asked whether these microRNAs can be used as plasma biomarkers for clinical CTCL monitoring. Patients with CTCL (n = 10) and controls with non-malignant conditions (n = 11) repeatedly donated plasma samples every ca. five months. MicroRNAs were detected in the plasma samples by specifically-primed RT-PCR followed by multivariate analyses of the miR expression dynamics. We herein established the plasma miR-classifier for detecting CTCL based on the miR-155 upregulation and miR-203/miR-205 downregulation with 100% specificity and 94% sensitivity. The 3-miR-score in the consecutive samples coincided with the clinical outcome of MF and SS patients such as the therapy response or changes in the clinical stage or tumor size. Quantitation of the selected microRNAs in plasma is a specific and straightforward approach for evaluating CTCL outcome representing, thus, a valuable tool for CTCL diagnostics and therapy response monitoring.

• MeSH
• cirkulující mikroRNA * MeSH
• kožní T-buněčný lymfom krev   diagnóza   genetika   terapie   MeSH
• kůže patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikro RNA genetika   MeSH
• nádorové biomarkery * MeSH
• prognóza MeSH
• protokoly antitumorózní kombinované chemoterapie terapeutické užití   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• staging nádorů MeSH
• stanovení celkové genové exprese MeSH
• studie případů a kontrol MeSH
• tekutá biopsie MeSH
• výsledek terapie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The imitation switch nuclear ATPase Smarca5 (Snf2h) is one of the most conserved chromatin remodeling factors. It exists in a variety of oligosubunit complexes that move DNA with respect to the histone octamer to generate regularly spaced nucleosomal arrays. Smarca5 interacts with different accessory proteins and represents a molecular motor for DNA replication, repair, and transcription. We deleted Smarca5 at the onset of definitive hematopoiesis (Vav1-iCre) and observed that animals die during late fetal development due to anemia. Hematopoietic stem and progenitor cells accumulated but their maturation toward erythroid and myeloid lineages was inhibited. Proerythroblasts were dysplastic while basophilic erythroblasts were blocked in G2/M and depleted. Smarca5 deficiency led to increased p53 levels, its activation at two residues, one associated with DNA damage (S15Ph°s) second with CBP/p300 (K376Ac), and finally activation of the p53 targets. We also deleted Smarca5 in committed erythroid cells (Epor-iCre) and observed that animals were anemic postnatally. Furthermore, 4-hydroxytamoxifen-mediated deletion of Smarca5 in the ex vivo cultures confirmed its requirement for erythroid cell proliferation. Thus, Smarca5 plays indispensable roles during early hematopoiesis and erythropoiesis. Stem Cells 2017;35:1614-1623.

• MeSH
• adenosintrifosfatasy nedostatek   metabolismus   MeSH
• anemie patologie   MeSH
• buněčná diferenciace * MeSH
• buněčný cyklus MeSH
• chromozomální proteiny, nehistonové nedostatek   metabolismus   MeSH
• delece genu MeSH
• erytroidní buňky cytologie   MeSH
• erytropoéza MeSH
• genotyp MeSH
• hematopoetické kmenové buňky cytologie   metabolismus   MeSH
• hematopoéza MeSH
• messenger RNA genetika   metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• nádorový supresorový protein p53 metabolismus   MeSH
• poškození DNA genetika   MeSH
• proliferace buněk MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

• MeSH
• chronická lymfatická leukemie * diagnóza   genetika   patologie   MeSH
• lidé MeSH
• lymfom z plášťových buněk * diagnóza   genetika   patologie   MeSH
• mikro RNA MeSH
• nádorová transformace buněk MeSH
• nádorové biomarkery analýza   MeSH
• stanovení celkové genové exprese MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH

Richter syndrome represents the transformation of the chronic lymphocytic leukemia (CLL) into an aggressive lymphoma, most frequently the diffuse large B-cell lymphoma (DLBCL). In this report we describe a patient with CLL, who developed a clonally-related pleomorphic highly-aggressive mantle cell lymphoma (MCL) after five cycles of a fludarabine-based second-line therapy for the first relapse of CLL. Molecular cytogenetic methods together with whole-exome sequencing revealed numerous gene alterations restricted to the MCL clone (apart from the canonical t(11;14)(q13;q32) translocation) including gain of one copy of ATM gene or emergence of TP53, CREBBP, NUP214, FUBP1 and SF3B1 gene mutations. Similarly, gene expression analysis revealed vast differences between the MCL and CLL transcriptome, including overexpression of cyclin D1, downregulation of cyclins D2 and D3, or downregulation of IL4R in the MCL clone. Backtracking analysis using quantitative PCR specifically detecting an MCL-restricted focal deletion of TP53 revealed that the pre-MCL clone appeared in the bone marrow and peripheral blood of the patient approximately 4 years before the clinical manifestation of MCL. Both molecular cytogenetic and sequencing data support the hypothesis of a slow development of the pre-MCL clone in parallel to CLL over several years, and thereby exclude the possibility that the transformation event occurred at the stage of the CLL relapse clone by mere t(11;14)(q13;q32) acquisition.

• MeSH
• chronická lymfatická leukemie genetika   metabolismus   patologie   MeSH
• difúzní velkobuněčný B-lymfom genetika   metabolismus   patologie   MeSH
• hybridizace in situ fluorescenční MeSH
• imunohistochemie MeSH
• lidé středního věku MeSH
• lidé MeSH
• lidské chromozomy, pár 11 MeSH
• lidské chromozomy, pár 14 MeSH
• lymfom z plášťových buněk genetika   metabolismus   patologie   MeSH
• nádorové biomarkery genetika   metabolismus   MeSH
• nádorový supresorový protein p53 genetika   metabolismus   MeSH
• translokace genetická MeSH
• ztráta heterozygozity MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

PURPOSE: Here, we studied whether amplicon next-generation deep sequencing (NGS) could improve the detection of emerging BCR-ABL1 kinase domain mutations in chronic phase chronic myeloid leukemia (CML) patients under tyrosine kinase inhibitor (TKI) treatment and discussed the clinical relevance of such sensitive mutational detection. METHODS: For NGS data evaluation including extraction of biologically relevant low-level variants from background error noise, we established and applied a robust and versatile bioinformatics approach. RESULTS: Results from a retrospective longitudinal analysis of 135 samples of 15 CML patients showed that NGS could have revealed emerging resistant mutants 2-11 months earlier than conventional sequencing. Interestingly, in cases who later failed first-line imatinib treatment, NGS revealed that TKI-resistant mutations were already detectable at the time of major or deeper molecular response. Identification of emerging mutations by NGS was mirrored by BCR-ABL1 transcript level expressed either fluctuations around 0.1 %(IS) or by slight transcript level increase. NGS also allowed tracing mutations that emerged during second-line TKI therapy back to the time of switchover. Compound mutants could be detected in three cases, but were not found to outcompete single mutants. CONCLUSIONS: This work points out, that next-generation deep sequencing, coupled with a robust bioinformatics approach for mutation calling, may be just in place to ensure reliable detection of emerging BCR-ABL1 mutations, allowing early therapy switch and selection of the most appropriate therapy. Further, prospective assessment of how to best integrate NGS in the molecular monitoring and clinical decision algorithms is warranted.

• MeSH
• antitumorózní látky terapeutické užití   MeSH
• bcr-abl fúzové proteiny genetika   MeSH
• benzamidy terapeutické užití   MeSH
• chronická myeloidní leukemie farmakoterapie   genetika   MeSH
• dospělí MeSH
• inhibitory proteinkinas terapeutické užití   MeSH
• lidé středního věku MeSH
• lidé MeSH
• longitudinální studie MeSH
• mutace účinky léků   MeSH
• piperaziny terapeutické užití   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• pyrimidiny terapeutické užití   MeSH
• retrospektivní studie MeSH
• senioři MeSH
• tyrosinkinasy antagonisté a inhibitory   MeSH
• výpočetní biologie MeSH
• vysoce účinné nukleotidové sekvenování * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH