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1.
Acta Neuropathol ; 139(2): 277-286, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31732806

RESUMO

Atypical teratoid/rhabdoid tumor (ATRT) is a highly malignant brain tumor predominantly occurring in infants. Mutations of the SMARCB1 gene are the characteristic genetic lesion. SMARCB1-mutant tumors in adolescents and adults are rare and may show uncommon histopathological and clinical features. Here we report seven SMARCB1-deficient intracranial tumors sharing distinct clinical, histopathological and molecular features. Median age of the four females and three males was 40 years (range 15-61 years). All tumors were located in the pineal region. Histopathologically, these tumors displayed spindled and epithelioid cells embedded in a desmoplastic stroma alternating with a variable extent of a loose myxoid matrix. All cases showed loss of nuclear SMARCB1/INI1 protein expression, expression of EMA and CD34 was frequent and the Ki67/MIB1 proliferation index was low in the majority of cases (median 3%). Three cases displayed heterozygous SMARCB1 deletions and two cases a homozygous SMARCB1 deletion. On sequencing, one tumor showed a 2 bp deletion in exon 4 (c.369_370del) and one a short duplication in exon 3 (c.237_276dup) both resulting in frameshift mutations. Most DNA methylation profiles were not classifiable using the Heidelberg Brain Tumor Classifier (version v11b4). By unsupervised t-SNE analysis and hierarchical clustering analysis, however, all tumors grouped closely together and showed similarities with ATRT-MYC. After a median observation period of 48 months, three patients were alive with stable disease, whereas one patient experienced tumor progression and three patients had succumbed to disease. In conclusion, our series represents an entity with distinct clinical, histopathological and molecular features showing epigenetic similarities with ATRT-MYC. We propose the designation desmoplastic myxoid tumor (DMT), SMARCB1-mutant, for these tumors.

2.
Pediatr Blood Cancer ; 67(1): e28022, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31571386

RESUMO

BACKGROUND: Case reports have portrayed spinal cord atypical teratoid/rhabdoid tumor (spATRT) as an aggressive form of ATRT. We conducted a retrospective European survey to collect data on clinical characteristics, molecular biology, treatment, and outcome of children with intramedullary spATRT. METHODS: Scrutinizing a French national series and the European Rhabdoid Registry database, we identified 13 patients (median age 32 months; metastatic disease at diagnosis, n = 6). Systemic postoperative chemotherapy was administered to all patients; three received intrathecal therapy and six were irradiated (craniospinal, n = 3; local, n = 3). RESULTS: Median observation time was 8 (range, 1-93) months. Progression-free and overall survival rates at 1 and (2 years) were 35.2% ± 13.9% (26.4% ± 12.9%) and 38.5% ± 13.5% (23.1% ± 11.7%). Four patients (ATRT-SHH, n = 2; ATRT-MYC, n = 1; DNA methylation subgroup not available, n = 1) achieved complete remission (CR); two of them are alive in CR 69 and 72 months from diagnosis. One patient relapsed after CR and is alive with progressive disease (PD) and one died of the disease. Three patients (ATRT-MYC, n = 2; subgroup not available, n = 1) died after 7 to 22 months due to PD after having achieved a partial remission (n = 1) or stabilization (n = 2). Five patients (ATRT-MYC, n = 2; subgroup not available, n = 3) developed early PD and died. One patient (ATRT-MYC) died of intracerebral hemorrhage prior to response evaluation. CONCLUSIONS: Long-term survival is achievable in selected patients with spATRT using aggressive multimodality treatment. Larger case series and detailed molecular analyses are needed to understand differences between spATRT and their inracranial counterparts and the group of extradural malignant rhabdoid tumors.

3.
Neuro Oncol ; 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31883020

RESUMO

BACKGROUND: Controversy exists as to what may be defined as standard of care (including markers for stratification) for patients with Atypical Teratoid Rhabdoid Tumors (ATRT). The European Rhabdoid Registry, EU-RHAB, recruits uniformly treated patients and offers standardized genetic and DNA methylation analyses. METHODS: Clinical, genetic and treatment data of 143 patients from 13 European countries were analyzed (2009 - 2017). Therapy consisted of surgery, anthracycline-based induction and either radiotherapy or high dose chemotherapy following a consensus among European experts. FISH, MLPA and sequencing were employed for assessment of somatic and germline mutations in SMARCB1. Molecular subgroups (ATRT-SHH, -TYR and -MYC) were determined using DNA-methylation arrays resulting in profiles of 84 tumors. RESULTS: Median age at diagnosis of 67 girls and 76 boys was 29.5 months. 5-year overall survival (OS) and event-free survival (EFS) were 34.7±4.5% and 30.5±4.2%. Tumors displayed allelic partial/whole gene deletions (66%; 122/186 alleles) or single nucleotide variants (34%; 64/186 alleles) of SMARCB1. Germline mutations were detected in 26% of ATRT (30/117). The patient cohort consisted of 47% ATRT-SHH (39/84), 33% ATRT-TYR (28/84), and 20% ATRT-MYC 17/84). Age <1 year, non-TYR signature (ATRT-SHH or -MYC), metastatic or synchronous tumors, germline mutation, incomplete remission and omission of radiotherapy were negative prognostic factors in univariate analyses (p<0.05). An adjusted multivariate model identified age <1 year and a non-TYR signature as independent negative predictors of OS: high risk (<1 year + non-TYR; 5-year OS = 0%), intermediate risk (<1 year + ATRT-TYR or ≥1 year + non-TYR; 5-year OS = 32.5±8.7%) and standard risk (≥1 year + ATRT-TYR, 5-year OS = 71.5±12.2%). CONCLUSIONS: Age and molecular subgroup status are independent risk factors for survival in children with ATRT. Our model warrants validation within future clinical trials.

4.
Blood Cancer J ; 9(12): 91, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748534

RESUMO

MYC is the most altered oncogene in human cancer, and belongs to a large family of genes, including MYCN and MYCL. Recently, while assessing the degree of correlation between MYC gene rearrangement and MYC protein expression in aggressive B-cell lymphomas, we observed few Burkitt lymphoma (BL) cases lacking MYC protein expression despite the translocation involving the MYC gene. Therefore, in the present study we aimed to better characterize such cases. Our results identified two sub-groups of MYC protein negative BL: one lacking detectable MYC protein expression but presenting MYCN mRNA and protein expression; the second characterized by the lack of both MYC and MYCN proteins but showing MYC mRNA. Interestingly, the two sub-groups presented a different pattern of SNVs affecting MYC gene family members that may induce the switch from MYC to MYCN. Particulary, MYCN-expressing cases show MYCN SNVs at interaction interface that stabilize the protein associated with loss-of-function of MYC. This finding highlights MYCN as a reliable diagnostic marker in such cases. Nevertheless, due to the overlapping clinic, morphology and immunohistochemistry (apart for MYC versus MYCN protein expression) of both sub-groups, the described cases represent bona fide BL according to the current criteria of the World Health Organization.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31677197

RESUMO

T-cell prolymphocytic leukemia (T-PLL) is an aggressive tumor with leukemic presentation of mature T-lymphocytes. Here, we aimed at characterizing the initial events in the molecular pathogenesis of T-PLL and particularly, at determining the point in T-cell differentiation when the hallmark oncogenic events, that is, inv(14)(q11q32)/t(14;14)(q11;q32) and t(X;14)(q28;q11) occur. To this end, we mined whole genome and transcriptome sequencing data of 17 and 11 T-PLL cases, respectively. Mapping of the 14q32.1 locus breakpoints identified only TCL1A, which was moreover significantly overexpressed in T-PLL as compared to benign CD4+ and CD8+ T-cells, as the only common oncogenic target of aberrations. In cases with t(14;14), the breakpoints mapped telomeric and in cases with inv(14) centromeric or in the 3'-untranslated region of TCL1A. Regarding the T-cell receptor alpha (TRA) locus-TCL1A breakpoint junctions, all 17 breakpoints involved recombination signal sequences and 15 junctions contained nontemplated (N-) nucleotides. All T-PLL cases studied carried in-frame TRA rearrangements on the intact allele, which skewed significantly toward usage of distal/central TRAV/TRAJ gene segments as compared to the illegitimate TRA rearrangements. Our findings suggest that the oncogenic TRA-TCL1A/MTCP1 rearrangements in T-PLL occur during opening of the TRA locus, that is, during the progression from CD4+ immature single positive to early double positive thymocyte stage, just before physiologic TCL1A expression is silenced. The cell carrying such an oncogenic event continues maturation and rearranges the second TRA allele to achieve a functional T-cell receptor. Thereafter, it switches off RAG and DNTT expression in line with the mature T-cell phenotype at presentation of T-PLL.

6.
J Clin Oncol ; 37(35): 3359-3368, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31498031

RESUMO

PURPOSE: MYC rearrangement (MYC-R) occurs in approximately 10% of diffuse large B-cell lymphomas (DLBCLs) and has been associated with poor prognosis in many studies. The impact of MYC-R on prognosis may be influenced by the MYC partner gene (immunoglobulin [IG] or a non-IG gene). We evaluated a large cohort of patients through the Lunenburg Lymphoma Biomarker Consortium to validate the prognostic significance of MYC-R (single-, double-, and triple-hit status) in DLBCL within the context of the MYC partner gene. METHODS: The study cohort included patients with histologically confirmed DLBCL morphology derived from large prospective trials and patient registries in Europe and North America who were uniformly treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone therapy or the like. Fluorescence in situ hybridization for the MYC, BCL2, BCL6, and IG heavy and light chain loci was used, and results were correlated with clinical outcomes. RESULTS: A total of 5,117 patients were identified of whom 2,383 (47%) had biopsy material available to assess for MYC-R. MYC-R was present in 264 (11%) of 2,383 patients and was associated with a significantly shorter progression-free and overall survival, with a strong time-dependent effect within the first 24 months after diagnosis. The adverse prognostic impact of MYC-R was only evident in patients with a concurrent rearrangement of BCL2 and/or BCL6 and an IG partner (hazard ratio, 2.4; 95% CI, 1.6 to 3.6; P < .001). CONCLUSION: The negative prognostic impact of MYC-R in DLBCL is largely observed in patients with MYC double hit/triple-hit disease in which MYC is translocated to an IG partner, and this effect is restricted to the first 2 years after diagnosis. Our results suggest that diagnostic strategies should be adopted to identify this high-risk cohort, and risk-adjusted therapeutic approaches should be refined further.

9.
Genes Chromosomes Cancer ; 58(6): 365-372, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30578714

RESUMO

Rare cases of hematological precursor neoplasms fulfill the diagnostic criteria of mixed phenotype acute leukemia (MPAL), characterized by expression patterns of at least two hematopoietic lineages, for which a highly aggressive behavior was reported. We present a series of 11 pediatric non-leukemic MPAL identified among 146 precursor lymphoblastic lymphomas included in the prospective trial Euro-LBL 02. Paraffin-embedded biopsies of 10 cases were suitable for molecular analyses using OncoScan assay (n = 7), fluorescence in situ hybridization (FISH; n = 7) or both (n = 5). Except for one case with biallelic KMT2A (MLL) breaks, all cases analyzed by FISH lacked the most common translocations defining molecular subsets of lymphoblastic leukemia/lymphomas. Two non-leukemic B-myeloid MPALs showed the typical genomic profile of hyperdiploid precursor B-cell lymphoblastic leukemia with gains of chromosomes 4, 6, 10, 14, 18, and 21. One B-T MPAL showed typical aberrations of T-cell lymphoblastic lymphoma, such as copy number neutral loss of heterozygosity (CNN-LOH) at 9p targeting a 9p21.3 deletion of CDKN2A and 11q12.2-qter affecting the ATM gene. ATM was also mutated in a T-myeloid MPAL case with additional loss at 7q21.2-q36.3 and mutation of NRAS, two alterations common in myeloid disorders. No recurrent regions of CNN-LOH were observed. The outcome under treatment was good with all patients being alive in first complete remission after treatment according to a protocol for precursor lymphoblastic lymphoma (follow-up 3-10 years, median: 4.9 years). In summary, the present series of non-leukemic MPALs widely lacked recurrently reported translocations in lymphoid/myeloid neoplasias and showed heterogeneous spectrum of chromosomal imbalances.


Assuntos
Fenótipo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética , Adolescente , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia/genética , Criança , Pré-Escolar , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , GTP Fosfo-Hidrolases/genética , Instabilidade Genômica/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/genética , Humanos , Masculino , Proteínas de Membrana/genética , Proteína de Leucina Linfoide-Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
10.
Blood ; 133(9): 962-966, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30567752

RESUMO

The new recently described provisional lymphoma category Burkitt-like lymphoma with 11q aberration comprises cases similar to Burkitt lymphoma (BL) on morphological, immunophenotypic and gene-expression levels but lacking the IG-MYC translocation. They are characterized by a peculiar imbalance pattern on chromosome 11, but the landscape of mutations is not yet described. Thus, we investigated 15 MYC-negative Burkitt-like lymphoma with 11q aberration (mnBLL,11q,) cases by copy-number analysis and whole-exome sequencing. We refined the regions of 11q imbalance and identified the INO80 complex-associated gene NFRKB as a positional candidate in 11q24.3. Next to recurrent gains in 12q13.11-q24.32 and 7q34-qter as well as losses in 13q32.3-q34, we identified 47 genes recurrently affected by protein-changing mutations (each ≥3 of 15 cases). Strikingly, we did not detect recurrent mutations in genes of the ID3-TCF3 axis or the SWI/SNF complex that are frequently altered in BL, or in genes frequently mutated in germinal center-derived B-cell lymphomas like KMT2D or CREBBP An exception is GNA13, which was mutated in 7 of 15 cases. We conclude that the genomic landscape of mnBLL,11q, differs from that of BL both at the chromosomal and mutational levels. Our findings implicate that mnBLL,11q, is a lymphoma category distinct from BL at the molecular level.


Assuntos
Biomarcadores Tumorais/genética , Linfoma de Burkitt/classificação , Linfoma de Burkitt/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 11/genética , Mutação , Adolescente , Adulto , Linfoma de Burkitt/patologia , Criança , Pré-Escolar , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Proto-Oncogênicas c-myc/genética , Estudos Retrospectivos , Adulto Jovem
11.
Blood ; 133(9): 940-951, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30538135

RESUMO

Mantle cell lymphoma (MCL) is characterized by the t(11;14)(q13;q32) translocation resulting in overexpression of cyclin D1. However, a small subset of cyclin D1- MCL has been recognized, and approximately one-half of them harbor CCND2 translocations while the primary event in cyclin D1-/D2- MCL remains elusive. To identify other potential mechanisms driving MCL pathogenesis, we investigated 56 cyclin D1-/SOX11+ MCL by fluorescence in situ hybridization (FISH), whole-genome/exome sequencing, and gene-expression and copy-number arrays. FISH with break-apart probes identified CCND2 rearrangements in 39 cases (70%) but not CCND3 rearrangements. We analyzed 3 of these negative cases by whole-genome/exome sequencing and identified IGK (n = 2) and IGL (n = 1) enhancer hijackings near CCND3 that were associated with cyclin D3 overexpression. By specific FISH probes, including the IGK enhancer region, we detected 10 additional cryptic IGK juxtapositions to CCND3 (6 cases) and CCND2 (4 cases) in MCL that overexpressed, respectively, these cyclins. A minor subset of 4 cyclin D1- MCL cases lacked cyclin D rearrangements and showed upregulation of CCNE1 and CCNE2. These cases had blastoid morphology, high genomic complexity, and CDKN2A and RB1 deletions. Both genomic and gene-expression profiles of cyclin D1- MCL cases were indistinguishable from cyclin D1+ MCL. In conclusion, virtually all cyclin D1- MCLs carry CCND2/CCND3 rearrangements with immunoglobulin genes, including a novel IGK/L enhancer hijacking mechanism. A subset of cyclin D1-/D2-/D3- MCL with aggressive features has cyclin E dysregulation. Specific FISH probes may allow the molecular identification and diagnosis of cyclin D1- MCL.


Assuntos
Ciclina D2/genética , Ciclina D3/genética , Elementos Facilitadores Genéticos , Rearranjo Gênico , Cadeias Leves de Imunoglobulina/genética , Linfoma de Célula do Manto/genética , Idoso , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Humanos , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição SOXC/genética , Translocação Genética
12.
J Clin Endocrinol Metab ; 103(12): 4617-4627, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30124873

RESUMO

Context: Inactivating mutations within the AR gene are present in only ~40% of individuals with clinically and hormonally diagnosed androgen insensitivity syndrome (AIS). Previous studies revealed the existence of an AR gene mutation-negative group of patients with AIS who have compromised androgen receptor (AR) function (AIS type II). Objective: To investigate whether AIS type II can be due to epigenetic repression of AR transcription. Design: Quantification of AR mRNA and AR proximal promoter CpG methylation levels in genital skin-derived fibroblasts (GFs) derived from patients with AIS type II and control individuals. Setting: University hospital endocrine research laboratory. Patients: GFs from control individuals (n = 11) and patients with AIS type II (n = 14). Main Outcome Measure(s): Measurement of AR mRNA and AR promoter CpG methylation as well as activity of AR proximal promoter in vitro. Results: Fifty-seven percent of individuals with AIS type II (n = 8) showed a reduced AR mRNA expression in their GFs. A significant inverse correlation was shown between AR mRNA abundance and methylation at two consecutive CpGs within the proximal AR promoter. Methylation of a 158-bp-long region containing these CpGs was sufficient to severely reduce reporter gene expression. This region was bound by the runt related transcription factor 1 (RUNX1). Ectopic expression of RUNX1 in HEK293T cells was able to inhibit reporter gene expression through this region. Conclusions: Aberrant CpGs methylation within the proximal AR promoter plays an important role in the control of AR gene expression and may result in AIS type II. We suggest that transcriptional modifiers, such as RUNX1, could play roles therein offering new perspectives for understanding androgen-mediated endocrine diseases.


Assuntos
Síndrome de Resistência a Andrógenos/genética , Metilação de DNA , Repressão Epigenética , Receptores Androgênicos/genética , Adolescente , Biópsia , Células Cultivadas , Criança , Pré-Escolar , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Ilhas de CpG/genética , Fibroblastos/metabolismo , Genitália Masculina , Células HEK293 , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Receptores Androgênicos/metabolismo , Pele/citologia , Pele/metabolismo , Pele/patologia
13.
Eur J Hum Genet ; 26(8): 1083-1093, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29706634

RESUMO

Germline variants that affect function are found in seven genes of the BAF chromatin-remodeling complex. They are linked to a broad range of diseases that, according to the gene affected, range from non-syndromic or syndromic neurodevelopmental disorders to low-grade tumors and malignancies. In the current meta-analysis, we evaluate genetic and clinical data from more than 400 families and 577 patients affected by BAF germline alterations. We focus on SMARCB1, including 43 unpublished patients from the EU-RHAB registry and our institution. For this gene, we further demonstrate whole gene as well as exon deletions and truncating variants to be associated with malignancy and early-onset disease. In contrast, non-truncating variants are associated with non-malignant disorders, such as Coffin-Siris syndrome or late-onset tumors like schwannoma or meningioma (p < 0.0001). SMARCB1 germline variants are distributed across the gene with variants in exons 1, 2, 8, and 9 being associated with low-grade entities, and single-nucleotide variants or indels outside of exon 9 that appear in patients with malignancies (p < 0.001). We attribute variants in specific BAF genes to certain disease entities. Finally, single-nucleotide variants and indels are sometimes detected in the healthy relatives of tumor patients, while Coffin-Siris syndrome and Nicolaides-Baraitser syndrome generally seem to appear de novo. Our findings add further information on the genotype-phenotype association of germline variants detected in genes of the BAF complex. Functional studies are urgently needed for a deeper understanding of BAF-related disorders and may take advantage from the comprehensive information gathered in this article.


Assuntos
Anormalidades Múltiplas/genética , Face/anormalidades , Mutação em Linhagem Germinativa , Deformidades Congênitas da Mão/genética , Deficiência Intelectual/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Micrognatismo/genética , Pescoço/anormalidades , Neurilemoma/genética , Proteína SMARCB1/genética , Anormalidades Múltiplas/patologia , Face/patologia , Deformidades Congênitas da Mão/patologia , Humanos , Deficiência Intelectual/patologia , Neoplasias Meníngeas/patologia , Meningioma/patologia , Micrognatismo/patologia , Pescoço/patologia , Neurilemoma/patologia , Fenótipo , Polimorfismo de Nucleotídeo Único
14.
Pediatr Blood Cancer ; 65(6): e26999, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29418059

RESUMO

BACKGROUND: Congenital rhabdoid tumors are rare and highly aggressive malignancies. In general, patients are considered to be incurable and are often treated using an exclusive, primarily palliative approach. METHODS: A prospective and retrospective collection of 42 patients from the European Rhabdoid Registry (EU-RHAB), France and Moscow (2006-2016) diagnosed within the first 28 days of life was evaluated. Genetic and clinical reference evaluation included SMARCB1 and/or SMARCA4 (fluorescence-in-situ-hybridization, multiplex ligation-dependent probe amplification, and sequencing) mutation analysis and immunohistochemistry. Forty-eight percent (20/42) of patients were treated according to the EU-RHAB therapy, 7% (3/42) according to the pilot approach Rhabdoid 2007, 33% (14/42) with individual schedules, and 12% (5/42) received no chemotherapy at all. RESULTS: Forty point five percent (17/42) of patients presented with extracranial rhabdoid tumors, 33.5% (14/42) with rhabdoid tumors of the central nervous system (atypical teratoid/rhabdoid tumor), and the remainder 26% (11/42) demonstrated synchronous tumors. Metastases at diagnosis were present in 52% (22/42) of patients. A germline mutation was detected in 66% (25/38) and was associated with a poor prognosis (4.2 ± 4.1% vs. 48 ± 16.4%, P < 0.00005). A gross total resection (GTR) was realized in 17%. A GTR (42.9 ± 18.7% vs. 4.9 ± 4.3%, P = 0.04), therapy according to a standardized approach (20.9 ± 8.7% vs. 7.1 ± 6.9 %, P = 0.0018), and a complete remission (CR) (23.6 ± 9.8% vs. 1.3 ± 3.6%, P = 0.04) were significant prognostic factors. CONCLUSIONS: The management of patients with congenital rhabdoid tumors requires a major multidisciplinary effort. In many instances, cure is not possible and a palliative approach is warranted. Our data indicate a positive impact of standardized therapeutic approaches on survival, making a tailored approach toward affected patients and their families mandatory.


Assuntos
Tumor Rabdoide/congênito , Tumor Rabdoide/terapia , Terapia Combinada , Europa (Continente) , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Tumor Rabdoide/patologia , Taxa de Sobrevida
15.
Am J Surg Pathol ; 42(4): 506-511, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29324471

RESUMO

Atypical teratoid/rhabdoid tumor (ATRT) is a highly malignant brain tumor predominantly encountered in infants. Mutations of the SMARCB1 gene are the characteristic genetic lesion. A small group of ATRT stands out clinically, because these tumors are located in the sellar region of adults. To investigate if sellar region ATRT in adults represents a molecular distinct entity, we characterized molecular alterations in 7 sellar region ATRTs in adults as compared with 150 pediatric ATRTs and 47 pituitary adenomas using SMARCB1 sequencing, multiplex ligation-dependent probe amplification and fluorescence in situ hybridization as well as DNA methylation profiling. The median age of the 6 female and 1 male patients was 56 years. On histopathologic examination, all tumors were malignant rhabdoid tumors showing loss of SMARCB1/INI1 protein expression. Two cases displayed compound heterozygous SMARCB1 point mutations, 3 cases showed heterozygous SMARCB1 deletions with point mutations of the other allele and 1 case a homozygous SMARCB1 deletion; in 1 case, underlying SMARCB1 alterations could not be identified. On unsupervised hierarchical cluster analysis of DNA methylation profiles, sellar region ATRTs did not form a distinct group, but clustered with ATRT-MYC, 1 of 3 recently described molecular subgroups of ATRT. On analysis of DNA methylation array intensity data, only 1 sellar region ATRT showed characteristic features of pediatric ATRT-MYC, that is, major copy number losses affecting the SMARCB1 region. In conclusion, these results suggest that sellar region ATRTs in adults form a clinically distinct entity with a different mutational spectrum, but epigenetic similarities with pediatric ATRTs of the ATRT-MYC subgroup.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Epigênese Genética , Neoplasias Hipofisárias/genética , Tumor Rabdoide/genética , Proteína SMARCB1/genética , Teratoma/genética , Adulto , Fatores Etários , Idoso , Feminino , Deleção de Genes , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Neoplasias Hipofisárias/patologia , Mutação Puntual , Tumor Rabdoide/patologia , Teratoma/patologia , Adulto Jovem
16.
Genes Chromosomes Cancer ; 57(5): 223-230, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29315962

RESUMO

Germ-line interstitial deletions involving the 14q32 chromosomal region, resulting in 14q32 deletion syndrome, are rare. DICER1 is a recently described cancer-predisposition gene located at 14q32.13. We report the case of a male child with a ∼5.8 Mbp 14q32.13q32.2 germ-line deletion, which included the full DICER1 locus. We reviewed available clinical and pathological material, and conducted genetic analyses. In addition to having congenital dysmorphic features, the child developed multiple DICER1 syndrome-related tumors before age 5 y: a pediatric cystic nephroma (pCN), a ciliary body medulloepithelioma (CBME), and a small lung cyst (consistent with occult pleuropulmonary blastoma Type I/Ir cysts seen in DICER1 mutation carriers). He also developed a cerebral spindle-cell sarcoma with myogenous differentiation. Our investigations revealed that the deletion encompassed 31 protein-coding genes. In addition to the germ-line DICER1 deletion, somatic DICER1 RNase IIIb mutations were found in the CBME (c.5437G > A, p.E1813K), pCN (c.5425G > A, p.G1809R), and sarcoma (c.5125G > A, p.D1709N). The sarcoma also harbored a somatic TP53 mutation: c.844C > T, p.R282W. Additional copy number alterations were identified in the CBME and sarcoma using an OncoScan array. Among the 8 cases with molecularly-defined 14q32 deletions involving DICER1 and for whom phenotypic information is available, our patient and one other developed DICER1-related tumors. Biallelic DICER1 mutations have not previously been reported to cause cerebral sarcoma, which now may be considered a rare manifestation of the DICER1 syndrome. Our study shows that DICER1-related tumors can occur in children with 14q32 deletions and suggests surveillance for such tumors may be warranted.


Assuntos
Deleção Cromossômica , RNA Helicases DEAD-box/genética , Síndromes Neoplásicas Hereditárias/genética , Ribonuclease III/genética , Criança , Cromossomos Humanos Par 14 , Mutação em Linhagem Germinativa , Humanos , Masculino , Deleção de Sequência
17.
Clin Epigenetics ; 9: 111, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29046733

RESUMO

BACKGROUND: Uniparental disomy of certain chromosomes are associated with a group of well-known genetic syndromes referred to as imprinting disorders. However, the extreme form of uniparental disomy affecting the whole genome is usually not compatible with life, with the exception of very rare cases of patients with mosaic genome-wide uniparental disomy reported in the literature. RESULTS: We here report on a fetus with intrauterine growth retardation and malformations observed on prenatal ultrasound leading to invasive prenatal testing. By cytogenetic (conventional karyotyping), molecular cytogenetic (QF-PCR, FISH, array), and methylation (MS-MLPA) analyses of amniotic fluid, we detected mosaicism for one cell line with genome-wide maternal uniparental disomy and a second diploid cell line of biparental inheritance with trisomy X due to paternal isodisomy X. As expected for this constellation, we observed DNA methylation changes at all imprinted loci investigated. CONCLUSIONS: This report adds new information on phenotypic outcome of mosaic genome-wide maternal uniparental disomy leading to an extreme form of multilocus imprinting disturbance. Moreover, the findings highlight the technical challenges of detecting these rare chromosome disorders prenatally.


Assuntos
Impressão Genômica , Ultrassonografia Pré-Natal/métodos , Dissomia Uniparental/genética , Adulto , Metilação de DNA , Feminino , Estudo de Associação Genômica Ampla , Humanos , Mosaicismo , Gravidez
18.
Histopathology ; 71(6): 960-971, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28730642

RESUMO

AIMS: Low-grade follicular lymphoma (FL) (grade 1/2, FL1/2) has an annual risk of transformation of ≈3%, which is associated with aberrations in CDKN2A/B, TP53, and MYC. As in diffuse large B-cell lymphoma, high MYC expression in transformed FL (tFL) might predict a MYC breakpoint. METHODS AND RESULTS: We quantified MYC expression by immunohistochemistry and digital analysis in 41 paired biopsies from 20 patients with FL1/2 with subsequent transformation and in four isolated biopsies of tFL. As controls, 28 biopsies of FL1/2 without transformation (median follow-up of 105 months) and nine biopsies of FL3A/B were analysed. In the 20 FL1/2-tFL pairs, MYC expression was significantly higher in tFL than in the initial FL1/2 biopsies (median 54% versus 6%; 7% in FL3A, and 35% in FL3B). MYC breaks (MYC-R) were detected in eight of 21 (38%) tFLs analysed by fluorescence in-situ hybridization (FISH), with a median MYC score of 86%. In two of the analysed tFL cases, the translocation was already detected in antecedent FL1/2. MYC partners were immunoglobulin (IG) loci in three of eight cases (one IGL, one IGH, and one IGK) and non-IG in five of eight cases (two PAX5, one BCL6, and two unknown). Of the eight MYC-R+ cases, six were BCL2+/MYC+ double-hit, one was BCL2+/BCL6+/MYC+ triple-hit, and one was MYC+ single-hit. All three IG-MYC+ cases showed a MYC expression level of >85%, whereas the five cases with a non-IG MYC partner had a wider range of expression (median 68%, range 13-86%). Among the 13 MYC-R- tFLs, two groups with almost dichotomous MYC expression could be observed (three cases showed ≥90% MYC expression), suggesting alternative mechanisms of MYC activation. CONCLUSIONS: we show an increase in MYC expression from FL1/2 to tFL. MYC breakpoints were present in ≈40% of the cases, which is markedly higher than in de novo DLBCL. MYC expression was uniformly high in cases with an IG-MYC translocation but much more heterogeneous and in part independent of the presence of a MYC break in non-IG-MYC and MYC-negative cases.


Assuntos
Regulação Neoplásica da Expressão Gênica , Linfoma Folicular/genética , Proteínas Proto-Oncogênicas c-myc/genética , Translocação Genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Quebra do Cromossomo , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Países Baixos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Estudos Retrospectivos
19.
Cancer Res ; 77(16): 4517-4529, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28646019

RESUMO

RAD51D is a key player in DNA repair by homologous recombination (HR), and RAD51D truncating variant carriers have an increased risk for ovarian cancer. However, the contribution of nontruncating RAD51D variants to cancer predisposition remains uncertain. Using deep sequencing and case-control genotyping studies, we show that in French Canadians, the missense RAD51D variant c.620C>T;p.S207L is highly prevalent and is associated with a significantly increased risk for ovarian high-grade serous carcinoma (HGSC; 3.8% cases vs. 0.2% controls). The frequency of the p.S207L variant did not significantly differ from that of controls in breast, endometrial, pancreas, or colorectal adenocarcinomas. Functionally, we show that this mutation impairs HR by disrupting the RAD51D-XRCC2 interaction and confers PARP inhibitor sensitivity. These results highlight the importance of a functional RAD51D-XRCC2 interaction to promote HR and prevent the development of HGSC. This study identifies c.620C>T;p.S207L as the first bona fide pathogenic RAD51D missense cancer susceptibility allele and supports the use of targeted PARP-inhibitor therapies in ovarian cancer patients carrying deleterious missense RAD51D variants. Cancer Res; 77(16); 4517-29. ©2017 AACR.


Assuntos
Proteínas de Ligação a DNA/genética , Mutação de Sentido Incorreto , Neoplasias Ovarianas/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/patologia , Linhagem , Polimorfismo de Nucleotídeo Único
20.
Pediatr Blood Cancer ; 64(10)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28371317

RESUMO

BACKGROUND: A high-level expression of the CRLF2 gene is frequent in precursor B-cell acute lymphoblastic leukemia (pB-ALL) and can be caused by different genetic aberrations. The presence of the most frequent alteration, the P2RY8/CRLF2 fusion, was shown to be associated with a high relapse incidence in children treated according to ALL-Berlin-Frankfurt-Münster (BFM) protocols, which is poorly understood. Moreover, the frequency of other alterations has not been systematically analyzed yet. PROCEDURE: CRLF2 mRNA expression and potential genetic aberrations causing a CRLF2 high expression were prospectively assessed in 1,105 patients treated according to the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP)-BFM ALL 2009 protocol. Additionally, we determined copy number alterations in selected B-cell differentiation genes for all CRLF2 high-expressing pB-ALL cases, as well as JAK2 and CRLF2 mutations. RESULTS: A CRLF2 high expression was detected in 26/178 (15%) T-cell acute lymphoblastic leukemia (T-ALL) cases, 21 of them (81%) had been stratified as high-risk patients by treatment response. In pB-ALL, a CRLF2 high expression was determined in 91/927 (10%) cases; the P2RY8/CRLF2 rearrangement in 44/91 (48%) of them, supernumerary copies of CRLF2 in 18/91 (20%), and, notably, the IGH/CRLF2 translocation was detected in 16/91 (18%). Remarkably, 7 of 16 (44%) patients with IGH/CRLF2 translocation had already relapsed. P2RY8/CRLF2- and IGH/CRLF2-positive samples (70 and 94%, respectively) were characterized by a high frequency of additional deletions in B-cell differentiation genes such as IKZF1 or PAX5. CONCLUSION: Our data suggest that this high frequency of genetic aberrations in the context of a high CRLF2 expression could contribute to the high risk of relapse in P2RY8/CRLF2- and IGH/CRLF2-positive ALL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Receptores de Citocinas/biossíntese , Adolescente , Asparaginase/administração & dosagem , Criança , Pré-Escolar , Daunorrubicina/administração & dosagem , Feminino , Rearranjo Gênico , Humanos , Fator de Transcrição Ikaros/biossíntese , Fator de Transcrição Ikaros/genética , Lactente , Masculino , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Fator de Transcrição PAX5/biossíntese , Fator de Transcrição PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prednisona/administração & dosagem , Receptores de Citocinas/genética , Receptores Purinérgicos P2Y/biossíntese , Receptores Purinérgicos P2Y/genética , Vincristina/administração & dosagem
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