Chromosomes carrying the mutation causing the fragile X [fra(X)] syndrome have been shown to have an unstable DNA sequence close to or within the fragile site. The length variation is located within a DNA fragment containing a CGG trinucleotide repeat which is unstable in both mitosis and meiosis. We have used the probe StB12.3 from the region to analyze the mutations and the methylation patterns in 21 families segregating for the fra(X) syndrome. Among 40 fra(X) males all showed an abnormal pattern. The normal 2.8 kb band was absent in 36 individuals and replaced by a heterogeneous smear of larger size. The remaining four were shown to be "mosaics" with the presence of both mutated, unmethylated and mutated, methylated fragments. We found four normal transmitting males, one which was a great-grandson of another normal transmitting male indicating that the pre-mutation can remain stable through two meioses in the female. In nine fra(X) positive females the abnormal pattern consisted of a smear, usually seen in affected males, in addition to the normal bands. Five of these females were mentally normal. Of clinical importance is the prediction of mental impairment in females. We suggest that this is not made by the detection of the full mutation alone, but rather by the degree of methylation of the normal X chromosome. Our results suggest that difference of clinical expression in monozygotic twins may be correlated with difference in methylation pattern. Six out of 33 fra(X) negative females at risk were diagnosed as carriers. Our observations indicate that molecular heterogeneity is responsible for variable expression of the fra(X) syndrome in both males and females.

• MeSH
• DNA sondy MeSH
• dvojčata monozygotní MeSH
• fenotyp MeSH
• heterozygot MeSH
• lidé MeSH
• metylace MeSH
• mutační analýza DNA MeSH
• nemoci u dvojčat genetika   MeSH
• rodokmen MeSH
• syndrom fragilního X * genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• práce podpořená grantem MeSH

Focal segmental glomerulosclerosis and minimal change disease represent frequent histological patterns of renal injury in patients with nephrotic syndrome. Few cases carrying NPHS2 gene variants have been described to date. Mutational analysis of the NPHS2 gene was performed in 50 Czech adult patients with histologically proved FSGS/MCD. The common p.P20L and p.R229Q polymorphisms of the NPHS2 gene were tested in 169 patients with IgA nephropathy and in 300 individuals of the control group. No mutation in the NPHS2 gene in patients with adult onset was identified. One homozygous mutation p.V290M in a patient with onset in early childhood was found. One new heterozygous variant in the non-conservative area of the NPHS2 gene, p.G97S, was identified in a patient with childhoodonset FSGS. In one adult patient, there were two polymorphisms, p.P20L and p.R229Q, in trans-heterozygous state, which could contribute to steroid-resistant nephrotic syndrome. The most common polymorphism p.R229Q was identified in 12 % of FSGS/ MCD patients, in 11.8 % of IGAN patients and in 10% of controls. The heterozygosity of p.R229Q polymorphism was similar in the IGAN group, with non-significantly higher prevalence in IGAN patients with progressive form of the disease (15.9 % versus 9.4 %). The prevalence of p.P20L polymorphism was not significantly different among the groups (6 % in FSGS patients, 1.8 % in IGAN patients, 1 % in the control group). To conclude, NPHS2 mutations are rare in patients with adult onset of FSGS/MCD. The R229Q polymorphism is frequent in the Czech population and probably could have some influence on IGAN.

• MeSH
• dospělí MeSH
• genetická predispozice k nemoci genetika   MeSH
• homozygot MeSH
• IgA nefropatie genetika   MeSH
• intracelulární signální peptidy a proteiny genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• membránové proteiny biosyntéza   genetika   MeSH
• mutace MeSH
• mutační analýza DNA metody   MeSH
• nefrotický syndrom imunologie   MeSH
• polymorfismus genetický MeSH
• prevalence MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH

Juvenile myelomonocytic leukemia (JMML) is an aggressive myeloproliferative disorder of early childhood characterized by mutations activating RAS signaling. Established clinical and genetic markers fail to fully recapitulate the clinical and biological heterogeneity of this disease. Here we report DNA methylome analysis and mutation profiling of 167 JMML samples. We identify three JMML subgroups with unique molecular and clinical characteristics. The high methylation group (HM) is characterized by somatic PTPN11 mutations and poor clinical outcome. The low methylation group is enriched for somatic NRAS and CBL mutations, as well as for Noonan patients, and has a good prognosis. The intermediate methylation group (IM) shows enrichment for monosomy 7 and somatic KRAS mutations. Hypermethylation is associated with repressed chromatin, genes regulated by RAS signaling, frequent co-occurrence of RAS pathway mutations and upregulation of DNMT1 and DNMT3B, suggesting a link between activation of the DNA methylation machinery and mutational patterns in JMML.

• MeSH
• biopsie MeSH
• chromatin genetika   metabolismus   MeSH
• dítě MeSH
• DNA-(cytosin-5-)methyltransferasa metabolismus   MeSH
• DNA-(cytosin-5)-methyltransferasa 1 metabolismus   MeSH
• epigenomika MeSH
• juvenilní myelomonocytární leukemie genetika   mortalita   patologie   terapie   MeSH
• kojenec MeSH
• lidé MeSH
• metylace DNA * MeSH
• mutace MeSH
• mutační analýza DNA MeSH
• Noonanové syndrom genetika   patologie   MeSH
• předškolní dítě MeSH
• prognóza MeSH
• prospektivní studie MeSH
• protinádorové látky terapeutické užití   MeSH
• protoonkogenní proteiny c-cbl MeSH
• protoonkogenní proteiny p21(ras) genetika   metabolismus   MeSH
• regulace genové exprese u leukemie MeSH
• signální transdukce genetika   MeSH
• transplantace hematopoetických kmenových buněk MeSH
• tyrosinfosfatasa nereceptorového typu 11 genetika   metabolismus   MeSH
• upregulace MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky MeSH
• multicentrická studie MeSH
• pozorovací studie MeSH
• práce podpořená grantem MeSH

PURPOSE: At the molecular level, myeloma is characterized by copy number abnormalities and recurrent translocations into the immunoglobulin heavy chain locus. Novel methods, such as massively parallel sequencing, have begun to describe the pattern of tumor-acquired mutations, but their clinical relevance has yet to be established. METHODS: We performed whole-exome sequencing for 463 patients who presented with myeloma and were enrolled onto the National Cancer Research Institute Myeloma XI trial, for whom complete molecular cytogenetic and clinical outcome data were available. RESULTS: We identified 15 significantly mutated genes: IRF4, KRAS, NRAS, MAX, HIST1H1E, RB1, EGR1, TP53, TRAF3, FAM46C, DIS3, BRAF, LTB, CYLD, and FGFR3. The mutational spectrum is dominated by mutations in the RAS (43%) and nuclear factor-κB (17%) pathways, but although they are prognostically neutral, they could be targeted therapeutically. Mutations in CCND1 and DNA repair pathway alterations (TP53, ATM, ATR, and ZNFHX4 mutations) are associated with a negative impact on survival. In contrast, those in IRF4 and EGR1 are associated with a favorable overall survival. We combined these novel mutation risk factors with the recurrent molecular adverse features and international staging system to generate an international staging system mutation score that can identify a high-risk population of patients who experience relapse and die prematurely. CONCLUSION: We have refined our understanding of genetic events in myeloma and identified clinically relevant mutations that may be used to better stratify patients at presentation.

• MeSH
• analýza přežití MeSH
• dospělí MeSH
• genetická predispozice k nemoci epidemiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mnohočetný myelom genetika   mortalita   patofyziologie   MeSH
• multivariační analýza MeSH
• mutační analýza DNA MeSH
• proporcionální rizikové modely MeSH
• prospektivní studie MeSH
• ras proteiny genetika   MeSH
• variabilita počtu kopií segmentů DNA genetika   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze III MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• srovnávací studie MeSH
• Geografické názvy
• Spojené království MeSH

BACKGROUND: We investigated the features of the genomic rearrangements in a cohort of 50 male individuals with proteolipid protein 1 (PLP1) copy number gain events who were ascertained with Pelizaeus-Merzbacher disease (PMD; MIM: 312080). We then compared our new data to previous structural variant mutagenesis studies involving the Xq22 region of the human genome. The aggregate data from 159 sequenced join-points (discontinuous sequences in the reference genome that are joined during the rearrangement process) were studied. Analysis of these data from 150 individuals enabled the spectrum and relative distribution of the underlying genomic mutational signatures to be delineated. METHODS: Genomic rearrangements in PMD individuals with PLP1 copy number gain events were investigated by high-density customized array or clinical chromosomal microarray analysis and breakpoint junction sequence analysis. RESULTS: High-density customized array showed that the majority of cases (33/50; ~ 66%) present with single duplications, although complex genomic rearrangements (CGRs) are also frequent (17/50; ~ 34%). Breakpoint mapping to nucleotide resolution revealed further previously unknown structural and sequence complexities, even in single duplications. Meta-analysis of all studied rearrangements that occur at the PLP1 locus showed that single duplications were found in ~ 54% of individuals and that, among all CGR cases, triplication flanked by duplications is the most frequent CGR array CGH pattern observed. Importantly, in ~ 32% of join-points, there is evidence for a mutational signature of microhomeology (highly similar yet imperfect sequence matches). CONCLUSIONS: These data reveal a high frequency of CGRs at the PLP1 locus and support the assertion that replication-based mechanisms are prominent contributors to the formation of CGRs at Xq22. We propose that microhomeology can facilitate template switching, by stabilizing strand annealing of the primer using W-C base complementarity, and is a mutational signature for replicative repair.

• MeSH
• body zlomu chromozomu MeSH
• duplikace genu MeSH
• genetická predispozice k nemoci MeSH
• genetické asociační studie MeSH
• genom lidský MeSH
• genomika metody   MeSH
• genová přestavba * MeSH
• jednonukleotidový polymorfismus MeSH
• lidé MeSH
• mutace * MeSH
• myelinový proteolipidový protein genetika   MeSH
• nestabilita genomu MeSH
• srovnávací genomová hybridizace MeSH
• variabilita počtu kopií segmentů DNA * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Acute myeloid leukemia (AML) can be grouped into morphologically or genetically defined subtypes. Today, the AML phenotype-genotype associations, that is, FAB/WHO (French-American-British/World Health Organization) definitions and recurrent molecular mutations, are not fully understood. Therefore, we evaluated the impact of molecular mutations on the AML differentiation stage by molecular profiling of 4373 adult de novo AML patients in 7 cytomorphological subtypes. We investigated mutations in 20 genes, including myeloid transcription factors (CEBPA, RUNX1), tumor suppressors (TP53, WT1), DNA modifiers (DNMT3A, IDH1/2, TET2), chromatin modifiers (ASXL1, MLL), signal transduction genes (FLT3, KRAS, NRAS) and NPM1. The most frequently mutated genes per cytomorphological subtype were RUNX1 in M0 (43%), NPM1 in M1 (42%), DNMT3A in M2 (26%), NPM1 in M4 (57%), M5a (49%) and M5b (70%) and TP53 in M6 (36%). Although some gene mutations were frequent in several cytomorphological subtypes, a series of associations of co-occurring mutations with distinct phenotypes were identified for molecularly defined subcohorts. FLT3, NPM1 and WT1 mutations were associated with an immature phenotype in myeloblastic AML, whereas other combinations involving ASXL1, RUNX1, MLL-PTD, CEBPA or KRAS were more frequent in myeloblastic AML with maturation. Within the NPM1 mutated subcohort, ASXL1 mutations were significantly associated with a monoblastic differentiation and DNMT3A mutations with a monocytic phenotype.

• MeSH
• akutní myeloidní leukemie klasifikace   genetika   patologie   MeSH
• dospělí MeSH
• genetické asociační studie MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• monocyty MeSH
• mutace * MeSH
• mutační rychlost MeSH
• prekurzorové buňky monocytů-makrofágů MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

TCF3-HLF-positive acute lymphoblastic leukemia (ALL) is currently incurable. Using an integrated approach, we uncovered distinct mutation, gene expression and drug response profiles in TCF3-HLF-positive and treatment-responsive TCF3-PBX1-positive ALL. We identified recurrent intragenic deletions of PAX5 or VPREB1 in constellation with the fusion of TCF3 and HLF. Moreover somatic mutations in the non-translocated allele of TCF3 and a reduction of PAX5 gene dosage in TCF3-HLF ALL suggest cooperation within a restricted genetic context. The enrichment for stem cell and myeloid features in the TCF3-HLF signature may reflect reprogramming by TCF3-HLF of a lymphoid-committed cell of origin toward a hybrid, drug-resistant hematopoietic state. Drug response profiling of matched patient-derived xenografts revealed a distinct profile for TCF3-HLF ALL with resistance to conventional chemotherapeutics but sensitivity to glucocorticoids, anthracyclines and agents in clinical development. Striking on-target sensitivity was achieved with the BCL2-specific inhibitor venetoclax (ABT-199). This integrated approach thus provides alternative treatment options for this deadly disease.

• MeSH
• aktivátorový protein specifický pro B-buňky genetika   MeSH
• akutní lymfatická leukemie farmakoterapie   genetika   mortalita   MeSH
• chemorezistence MeSH
• exprese genu MeSH
• fúzní onkogenní proteiny genetika   metabolismus   MeSH
• genetické asociační studie MeSH
• genomika MeSH
• inhibiční koncentrace 50 MeSH
• Kaplanův-Meierův odhad MeSH
• kohortové studie MeSH
• kokultivační techniky MeSH
• lidé MeSH
• mutace MeSH
• mutační analýza DNA MeSH
• myši inbrední NOD MeSH
• myši SCID MeSH
• náhradní lehké řetězce imunoglobulinů genetika   MeSH
• protinádorové látky farmakologie   terapeutické užití   MeSH
• sekvenční delece MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The gene coding for histone methyltransferase KMT2D is found among the top mutated genes in upper tract urothelial carcinoma (UTUC); however, there is a lack of data regarding its association with clinicopathologic features as well as survival outcomes. Therefore, we aimed to investigate KMT2D expression, mutation patterns, and their utility as prognostic biomarkers in patients with UTUC. A single-center study was conducted on tumor specimens from 51 patients treated with radical nephroureterectomy (RNU). Analysis of KMT2D protein expression was performed using immunohistochemistry (IHC). Customized next-generation sequencing (NGS) was used to assess alterations in KMT2D exons. Cox regression was used to assess the relationship of KMT2D protein expression and mutational status with survival outcomes. KMT2D expression was increased in patients with a previous history of bladder cancer (25% vs. 0%, p = 0.02). The NGS analysis of KMT2D exons in 27 UTUC tumors revealed a significant association between pathogenic KMT2D variants and tumor location (p = 0.02). Pathogenic KMT2D variants were predominantly found in patients with non-pelvic or multifocal tumors (60% vs. 14%), while the majority of patients with a pelvic tumor location (81% vs. 20%) did not harbor pathogenic KMT2D alterations. Both IHC and NGS analyses of KMT2D failed to detect a statistically significant association between KMT2D protein or KMT2D gene alteration status and clinical variables such as stage/grade of the disease or survival outcomes (all p > 0.05). KMT2D alterations and protein expression were associated with UTUC features such as multifocality, ureteral location, and previous bladder cancer. While KMT2D protein expression and KMT2D mutational status do not seem to have prognostic value in UTUC, they appear to add information to improve clinical decision-making regarding the type of therapy.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Aberrant epigenetic patterns are a hallmark of acute myeloid leukemia (AML). Mutations in profound epigenetic regulators DNMT3A and IDH1/2 often occur concurrently in AML. OBJECTIVES: The aim was to analyze DNA methylation, hydroxymethylation and mRNA expression profiles in AML with mutations in DNMT3A and IDH1/2 (individually and in combinations). METHODS: Infinium MethylationEPIC BeadChip (Illumina) covering 850,000 CpGs was utilized. The validation of hydroxy-/methylation data was done by pyrosequencing. HumanHT-12 v4 Expression BeadChip (Illumina) was used for expression examination. RESULTS: Hierarchical clustering analysis of DNA hydroxy-/methylation data revealed clusters corresponding to DNMT3A and IDH1/2 mutations and CD34+ healthy controls. Samples with concurrent presence of DNMT3A and IDH1/2 mutations displayed mixed DNA hydroxy-/methylation profile with preferential clustering to healthy controls. Numbers and levels of DNA hydroxymethylation were low. Uniformly hypermethylated loci in AML patients with IDH1/2 mutations were enriched for immune response and apoptosis related genes, among which hypermethylation of granzyme B (GZMB) was found to be associated with inferior overall survival of AML patients (P= 0.035). CONCLUSIONS: Distinct molecular background results in specific DNA hydroxy-/methylation profiles in AML. Site-specific DNA hydroxymethylation changes are much less frequent in AML pathogenesis compared to DNA methylation. Methylation levels of enhancer located upstream GZMB gene might contribute to AML prognostication models.

• MeSH
• akutní myeloidní leukemie genetika   metabolismus   MeSH
• DNA-(cytosin-5-)methyltransferasa genetika   MeSH
• granzymy genetika   MeSH
• isocitrátdehydrogenasa genetika   MeSH
• leukocyty mononukleární metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metylace DNA * MeSH
• mutace MeSH
• prognóza MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• stanovení celkové genové exprese 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

We performed immunohistochemical assessment of p53 expression and TP53 mutational analysis of 15 malignant neoplasms arising from preexisting benign cylindroma, spiradenoma, and spiradenocylindroma, sporadic or associated with Brooke-Spiegler syndrome. At least weak and focal p53 positivity was present in 13 of the 15 lesions. Successful PCR and sequencing were possible in 12 of the 15 cases. In one case only there were 2 p53 mutations, one being a c.673-1G>A splice-site mutation in the 3'-end of intron 6 (position--g.15289G>A, contig gb.AY838696.1) and the second being a c.743G>A (p.R248Q) mutation in exon 7 (position--15360G>A, contig gb.AY838696.1). Single nucleotide polymorphisms were detected in all 12 malignant cases analyzed. As a control group, we included 12 randomly selected sporadic cases of spiradenoma (n = 5), cylindroma (n = 4), and spiradenocylindroma (n = 3). None of the 12 benign control group cases harbored a TP53 mutation, whereas all 12 demonstrated single nucleotide polymorphisms identical to those detected in the malignant tumor group. Immunohistochemically, 1 cylindroma and 2 spiradenomas demonstrated weak and focal p53 positivity. In conclusion, we found a fairly high rate of p53 expression in malignant neoplasms arising from preexisting benign spiradenomas, cylindromas, and spiradenocylindromas. However, the mutation rate of TP53 was low. Whereas immunostaining for p53 has been suggested as an adjunct tool to differentiate benign spiradenoma, cylindroma, and spiradenocylindroma from their malignant counterparts, its utility is limited by its heterogeneous pattern of expression, especially the sometimes lack of staining in clearly malignant areas and the occurrence of focal, weak positivity in the benign residua or in unequivocally benign neoplasms.

• MeSH
• adenoidně cystický karcinom genetika   patologie   MeSH
• adenom genetika   patologie   MeSH
• bodová mutace MeSH
• DNA nádorová genetika   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mnohočetné primární nádory genetika   patologie   MeSH
• mutační analýza DNA MeSH
• nádorový supresorový protein p53 genetika   metabolismus   MeSH
• nádory potních žláz genetika   patologie   MeSH
• regulace genové exprese u nádorů MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• syndrom MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH