RESUMO
Inflammasome complexes function as key innate immune effectors that trigger inflammation in response to pathogen- and danger-associated signals. Here, we report that germline mutations in the inflammasome sensor NLRP1 cause two overlapping skin disorders: multiple self-healing palmoplantar carcinoma (MSPC) and familial keratosis lichenoides chronica (FKLC). We find that NLRP1 is the most prominent inflammasome sensor in human skin, and all pathogenic NLRP1 mutations are gain-of-function alleles that predispose to inflammasome activation. Mechanistically, NLRP1 mutations lead to increased self-oligomerization by disrupting the PYD and LRR domains, which are essential in maintaining NLRP1 as an inactive monomer. Primary keratinocytes from patients experience spontaneous inflammasome activation and paracrine IL-1 signaling, which is sufficient to cause skin inflammation and epidermal hyperplasia. Our findings establish a group of non-fever inflammasome disorders, uncover an unexpected auto-inhibitory function for the pyrin domain, and provide the first genetic evidence linking NLRP1 to skin inflammatory syndromes and skin cancer predisposition.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Carcinoma/genética , Predisposição Genética para Doença , Inflamassomos/metabolismo , Ceratose/genética , Neoplasias Cutâneas/genética , Proteínas Adaptadoras de Transdução de Sinal/química , Sequência de Aminoácidos , Proteínas Reguladoras de Apoptose/química , Carcinoma/patologia , Cromossomos Humanos Par 17/genética , Epiderme/patologia , Mutação em Linhagem Germinativa , Humanos , Hiperplasia/genética , Hiperplasia/patologia , Inflamassomos/genética , Interleucina-1/metabolismo , Ceratose/patologia , Proteínas NLR , Comunicação Parácrina , Linhagem , Domínios Proteicos , Pirina/química , Transdução de Sinais , Neoplasias Cutâneas/patologia , SíndromeRESUMO
Genomic instability is a hallmark of cancer, and has a central role in the initiation and development of breast cancer1,2. The success of poly-ADP ribose polymerase inhibitors in the treatment of breast cancers that are deficient in homologous recombination exemplifies the utility of synthetically lethal genetic interactions in the treatment of breast cancers that are driven by genomic instability3. Given that defects in homologous recombination are present in only a subset of breast cancers, there is a need to identify additional driver mechanisms for genomic instability and targeted strategies to exploit these defects in the treatment of cancer. Here we show that centrosome depletion induces synthetic lethality in cancer cells that contain the 17q23 amplicon, a recurrent copy number aberration that defines about 9% of all primary breast cancer tumours and is associated with high levels of genomic instability4-6. Specifically, inhibition of polo-like kinase 4 (PLK4) using small molecules leads to centrosome depletion, which triggers mitotic catastrophe in cells that exhibit amplicon-directed overexpression of TRIM37. To explain this effect, we identify TRIM37 as a negative regulator of centrosomal pericentriolar material. In 17q23-amplified cells that lack centrosomes, increased levels of TRIM37 block the formation of foci that comprise pericentriolar material-these foci are structures with a microtubule-nucleating capacity that are required for successful cell division in the absence of centrosomes. Finally, we find that the overexpression of TRIM37 causes genomic instability by delaying centrosome maturation and separation at mitotic entry, and thereby increases the frequency of mitotic errors. Collectively, these findings highlight TRIM37-dependent genomic instability as a putative driver event in 17q23-amplified breast cancer and provide a rationale for the use of centrosome-targeting therapeutic agents in treating these cancers.
Assuntos
Neoplasias da Mama/genética , Centrossomo/metabolismo , Centrossomo/patologia , Cromossomos Humanos Par 17/genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Centrossomo/efeitos dos fármacos , Feminino , Fase G2 , Instabilidade Genômica , Humanos , Mitose/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
Centrosomes catalyse the formation of microtubules needed to assemble the mitotic spindle apparatus1. Centrosomes themselves duplicate once per cell cycle, in a process that is controlled by the serine/threonine protein kinase PLK4 (refs. 2,3). When PLK4 is chemically inhibited, cell division proceeds without centrosome duplication, generating centrosome-less cells that exhibit delayed, acentrosomal spindle assembly4. Whether PLK4 inhibitors can be leveraged as a treatment for cancer is not yet clear. Here we show that acentrosomal spindle assembly following PLK4 inhibition depends on levels of the centrosomal ubiquitin ligase TRIM37. Low TRIM37 levels accelerate acentrosomal spindle assembly and improve proliferation following PLK4 inhibition, whereas high TRIM37 levels inhibit acentrosomal spindle assembly, leading to mitotic failure and cessation of proliferation. The Chr17q region containing the TRIM37 gene is frequently amplified in neuroblastoma and in breast cancer5-8, rendering these cancer types highly sensitive to PLK4 inhibition. We find that inactivating TRIM37 improves acentrosomal mitosis because TRIM37 prevents PLK4 from self-assembling into centrosome-independent condensates that serve as ectopic microtubule-organizing centres. By contrast, elevated TRIM37 expression inhibits acentrosomal spindle assembly through a distinct mechanism that involves degradation of the centrosomal component CEP192. Thus, TRIM37 is an essential determinant of mitotic vulnerability to PLK4 inhibition. Linkage of TRIM37 to prevalent cancer-associated genomic changes-including 17q gain in neuroblastoma and 17q23 amplification in breast cancer-may offer an opportunity to use PLK4 inhibition to trigger selective mitotic failure and provide new avenues to treatments for these cancers.
Assuntos
Mitose/efeitos dos fármacos , Mitose/genética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona/metabolismo , Cromossomos Humanos Par 17/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Centro Organizador dos Microtúbulos/efeitos dos fármacos , Centro Organizador dos Microtúbulos/metabolismo , Neoplasias/enzimologia , Neoplasias/patologia , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade Proteica , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Fuso Acromático/efeitos dos fármacos , Fuso Acromático/metabolismo , Sulfonas/farmacologia , Sulfonas/uso terapêutico , Ubiquitina/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Single nucleotide polymorphisms (SNPs) in genes on chromosome 17q12-q21 are associated with childhood-onset asthma and rhinovirus-induced wheeze. There are few mechanistic data linking chromosome 17q12-q21 to wheezing illness. OBJECTIVE: We investigated whether 17q12-q21 risk alleles were associated with impaired interferon responses to rhinovirus. METHODS: In a population-based birth cohort of European ancestry, we stimulated peripheral blood mononuclear cells with rhinovirus A1 (RV-A1) and rhinovirus A16 (RV-A16) and measured IFN and IFN-induced C-X-C motif chemokine ligand 10 (aka IP10) responses in supernatants. We investigated associations between virus-induced cytokines and 6 SNPs in 17q12-q21. Bayesian profile regression was applied to identify clusters of individuals with different immune response profiles and genetic variants. RESULTS: Five SNPs (in high linkage disequilibrium, r2 ≥ 0.8) were significantly associated with RV-A1-induced IFN-ß (rs9303277, P = .010; rs11557467, P = .012; rs2290400, P = .006; rs7216389, P = .008; rs8079416, P = .005). A reduction in RV-A1-induced IFN-ß was observed among individuals with asthma risk alleles. There were no significant associations for RV-A1-induced IFN-α or CXCL10, or for any RV-A16-induced IFN/CXCL10. Bayesian profile regression analysis identified 3 clusters that differed in IFN-ß induction to RV-A1 (low, medium, high). The typical genetic profile of the cluster associated with low RV-A1-induced IFN-ß responses was characterized by a very high probability of being homozygous for the asthma risk allele for all SNPs. Children with persistent wheeze were almost 3 times more likely to be in clusters with reduced/average RV-A1-induced IFN-ß responses than in the high immune response cluster. CONCLUSIONS: Polymorphisms on chromosome 17q12-q21 are associated with rhinovirus-induced IFN-ß, suggesting a novel mechanism-impaired IFN-ß induction-links 17q12-q21 risk alleles with asthma/wheeze.
Assuntos
Cromossomos Humanos Par 17 , Polimorfismo de Nucleotídeo Único , Rhinovirus , Humanos , Cromossomos Humanos Par 17/genética , Masculino , Feminino , Asma/genética , Asma/imunologia , Interferons , Criança , Sons Respiratórios/genética , Sons Respiratórios/imunologia , Infecções por Picornaviridae/imunologia , Infecções por Picornaviridae/genética , Predisposição Genética para Doença , Quimiocina CXCL10/genética , Leucócitos Mononucleares/imunologia , Pré-EscolarRESUMO
17p13 deletions including TP53 and other genes represent a common cause for reduced/lost p53 function in tumor cells. In this study, we analyzed the impact of 17p13 (TP53) deletions and p53 expression on tumor aggressiveness and patient prognosis in urothelial carcinoma. The 17p13 copy number status was analyzed by fluorescence in situ hybridization (FISH) on more than 2700 urothelial bladder carcinomas in a tissue microarray format. 17p13 deletion data were compared to p53 expression data measured by immunohistochemistry (IHC) in a previous study. Different types of p53 alterations were compared with tumor phenotype and clinical outcome data. Deletions of 17p13 occurred in 23% of 2185 analyzable carcinomas. The fraction of tumors with 17p13 deletions increased from pTa G2 low (9%) to pTa G3 (24%, p < 0.0001). In muscle-invasive carcinomas, 17p13 deletions were associated with advanced pT stage (p = 0.0246), but unrelated to patient prognosis (p > 0.5). 17p13 deletions were significantly related to p53 immunostaining (p = 0.0375). 17p13 deletions were most common in tumors with complete lack of p53 staining (31%), which supports the concept that many of these tumors have a complete loss of p53 function (p53 null phenotype). 17p13 deletions were also increased in tumors with high p53 staining (25%). In conclusion, 17p13 deletions were most commonly seen in p53 negative cancers, supporting their role as a cause for the p53 null phenotype in urothelial cancer. The association of 17p13 deletions with high grade and advanced pT stage may reflect increasing genomic instability going along with stage and grade progression.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 17 , Fenótipo , Proteína Supressora de Tumor p53 , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Prognóstico , Cromossomos Humanos Par 17/genética , Proteína Supressora de Tumor p53/genética , Masculino , Feminino , Hibridização in Situ Fluorescente , Idoso , Pessoa de Meia-IdadeRESUMO
NF1 microdeletion syndrome, accounting for 5-11% of NF1 patients, is caused by a deletion in the NF1 region and it is generally characterized by a severe phenotype. Although 70% of NF1 microdeletion patients presents the same 1.4 Mb type-I deletion, some patients may show additional clinical features. Therefore, the contribution of several pathogenic mechanisms, besides haploinsufficiency of some genes within the deletion interval, is expected and needs to be defined. We investigated an altered expression of deletion flanking genes by qPCR in patients with type-1 NF1 deletion, compared to healthy donors, possibly contributing to the clinical traits of NF1 microdeletion syndrome. In addition, the 1.4-Mb deletion leads to changes in the 3D chromatin structure in the 17q11.2 region. Specifically, this deletion alters DNA-DNA interactions in the regions flanking the breakpoints, as demonstrated by our 4C-seq analysis. This alteration likely causes position effect on the expression of deletion flanking genes.Interestingly, 4C-seq analysis revealed that in microdeletion patients, an interaction was established between the RHOT1 promoter and the SLC6A4 gene, which showed increased expression. We performed NGS on putative modifier genes, and identified two "likely pathogenic" rare variants in RAS pathway, possibly contributing to incidental phenotypic features.This study provides new insights into understanding the pathogenesis of NF1 microdeletion syndrome and suggests a novel pathomechanism that contributes to the expression phenotype in addition to haploinsufficiency of genes located within the deletion.This is a pivotal approach that can be applied to unravel microdeletion syndromes, improving precision medicine, prognosis and patients' follow-up.
Assuntos
Deleção Cromossômica , Epigênese Genética , Haploinsuficiência , Neurofibromatose 1 , Humanos , Neurofibromatose 1/genética , Feminino , Masculino , Neurofibromina 1/genética , Cromossomos Humanos Par 17/genética , Fenótipo , Criança , Regiões Promotoras GenéticasRESUMO
The potential prognostic influence of genetic aberrations on chronic lymphocytic leukaemia (CLL) can vary based on various factors, such as the immunoglobulin heavy variable (IGHV) status. We conducted an integrative analysis on genetic abnormalities identified through cytogenetics and targeted next-generation sequencing in 536 CLL patients receiving first-line chemo(immuno)therapies (CIT) as part of two prospective trials. We evaluated the prognostic implications of the main abnormalities, with specific attention to their relative impact according to IGHV status. In the entire cohort, unmutated (UM)-IGHV, complex karyotype, del(11q) and ATM mutations correlated significantly with shorter progression-free survival (PFS). Focusing on the subset of mutated IGHV (M-IGHV) patients, univariate analysis showed that complex karyotype, del(11q), SF3B1 and SAMHD1 mutations were associated with significant lower PFS. The prognostic influence varied based on the patient's IGHV status, as these abnormalities did not affect outcomes in the UM-IGHV subgroup. TP53 mutations had no significant impact on outcomes in the M-IGHV subgroup. Our findings highlight the diverse prognostic influence of genetic aberrations depending on the IGHV status in symptomatic CLL patients receiving first-line CIT. The prognosis of gene mutations and cytogenetic abnormalities needs to be investigated with a compartmentalized methodology, taking into account the IGVH status of patients receiving first-line BTK and/or BCL2 inhibitors.
Assuntos
Cromossomos Humanos Par 17 , Cadeias Pesadas de Imunoglobulinas , Leucemia Linfocítica Crônica de Células B , Mutação , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Prognóstico , Cadeias Pesadas de Imunoglobulinas/genética , Estudos Prospectivos , Cromossomos Humanos Par 17/genética , Deleção Cromossômica , Adulto , Idoso de 80 Anos ou mais , Região Variável de Imunoglobulina/genética , Imunoterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
The demographic history of human populations in North Africa has been characterized by complex migration processes that have determined the current genetic structure of these populations. We examined the autosomal markers of eight sampled populations in northern Africa (Tunisia and Libya) to explore their genetic structure and to place them in a global context. We genotyped a set of 30 autosomal single-nucleotide polymorphisms (SNPs) extending 9.5 Mb and encompassing the 17q21 inversion region. Our data include 403 individuals from Tunisia and Libya. To put our populations in the global context, we analyzed our data in comparison with other populations, including those of the 1000 Genomes Project. To evaluate the data, we conducted genetic diversity, principal component, STRUCTURE, and haplotype analyses. The analysis of genetic composition revealed the genetic heterogeneity of North African populations. The principal component and STRUCTURE analyses converged and revealed the intermediate position of North Africans between Europeans and Asians. Haplotypic analysis demonstrated that the normal (H1) and inverted (H2) polymorphisms in the chromosome 17q21 region occur in North Africa at frequencies similar to those found in European and Southwest Asian populations. The results highlight the complex demographic history of North Africa, reflecting the influence of genetic flow from Europe and the Near East that dates to the prehistoric period. These gene flows added to demographic factors (inbreeding, endogamy), natural factors (topography, Sahara), and cultural factors that play a role in the emergence of the diverse and heterogeneous genetic structures of North African populations. This study contributes to a better understanding of the complex structure of North African populations.
Assuntos
Cromossomos Humanos Par 17 , Variação Genética , Genética Populacional , Haplótipos , Polimorfismo de Nucleotídeo Único , Humanos , Cromossomos Humanos Par 17/genética , África do Norte , População Negra/genética , Tunísia , Análise de Componente Principal , Líbia , Frequência do Gene , População do Norte da ÁfricaRESUMO
Breast cancer (BC) with average human epidermal growth factor receptor 2 (HER2) signals/cell ≥6 and HER2/chromosome enumeration probe 17 (CEP17) ratio <2 (in situ hybridization [ISH] group 3) is very rare, accounting for 0.4% to 3.0% of cases sent for the dual-probe ISH assay. Although such patients are currently eligible for treatment with HER2-targeted therapy, their characteristics and outcomes remain poorly understood. Sixty-two BCs with equivocal HER2 immunohistochemical score (2+) and reflex ISH group 3 results were identified across 4 institutions. Available clinicopathologic characteristics, MammaPrint and BluePrint molecular results, and follow-up information were retrospectively analyzed. Most BCs with HER2 equivocal immunohistochemical and ISH group 3 results were histologic grade 2 or 3 (100%), estrogen receptor (ER) positive (90.3%), with an average HER2 signals/cell of 7.3. Molecular profiles revealed that 80% (16/20) of tumors were luminal subtypes, and HER2 molecular subtype was identified in 10% of tumors (2/20). Twelve (19.4%) out of 62 patients developed local recurrence and/or distant metastasis with a median follow-up of 50 months. One (10%) of 10 patients achieved pathologic complete response after neoadjuvant chemotherapy. Forty-nine (79%) out of 62 patients completed anti-HER2 agents, and exploratory analysis showed no statistically significant difference in disease outcomes between patients who completed anti-HER2 treatment and those who did not. Univariate analysis revealed advanced clinical stage, and ER/progesterone receptor negativity was associated with unfavorable disease outcomes, and exploratory multivariate analysis demonstrated that clinical stage was the most significant factor associated with disease outcomes in the studied population. These findings increase our understanding of this rare, but clinically important HER2 category. Large-scale prospective randomized studies are needed to further evaluate the role of perioperative HER2-targeted therapy in this patient population.
Assuntos
Biomarcadores Tumorais , Neoplasias da Mama , Imuno-Histoquímica , Receptor ErbB-2 , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/análise , Pessoa de Meia-Idade , Adulto , Idoso , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Hibridização In Situ , Cromossomos Humanos Par 17/genéticaRESUMO
Dermatofibrosarcoma protuberans (DFSP) is a cutaneous sarcoma with a high propensity for local invasion and recurrence. Although it is a rare event, the occurrence of multiple tumors in a single patient raises a diagnostic dilemma, as metastatic disease should be differentiated from multiple primary malignant events. In more than 90% of DFSP, a pathogenic t(17;22) translocation leads to the expression of COL1A1::PDGFB fusion transcripts. Karyotype analysis, fluorescence in situ hybridization, and RT-PCR can be useful ancillary studies in detecting this characteristic rearrangement, and sequencing of the fusion transcript can be used to support a clonal origin in metastatic and multifocal disease. However, previous reports have demonstrated variable sensitivity of these assays, in part due to the high sequence variability of the COL1A1::PDGFB fusion. Here, we report a patient who developed two distinct DFSP tumors over the course of 7 years. Chromosomal microarray analysis identified distinctive genomic alterations in the two tumors, supporting the occurrence of multiple primary malignant events.
Assuntos
Dermatofibrossarcoma , Proteínas de Fusão Oncogênica , Neoplasias Cutâneas , Humanos , Masculino , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 22/genética , Cadeia alfa 1 do Colágeno Tipo I , Dermatofibrossarcoma/genética , Dermatofibrossarcoma/patologia , Dermatofibrossarcoma/diagnóstico , Hibridização in Situ Fluorescente/métodos , Análise em Microsséries/métodos , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Proteínas de Fusão Oncogênica/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Translocação Genética , Pessoa de Meia-IdadeRESUMO
BACKGROUND: TBX6, a member of the T-box gene family, encodes the transcription factor box 6 that is critical for somite segmentation in vertebrates. It is known that the compound heterozygosity of disruptive variants in trans with a common hypomorphic risk haplotype (T-C-A) in the TBX6 gene contribute to 10% of congenital scoliosis (CS) cases. The deletion of chromosome 17q12 is a rare cytogenetic abnormality, which often leads to renal cysts and diabetes mellitus. However, the affected individuals often exhibit clinical heterogeneity and incomplete penetrance. METHODS: We here present a Chinese fetus who was shown to have CS by ultrasound examination at 17 weeks of gestation. Trio whole-exome sequencing (WES) was performed to investigate the underlying genetic defects of the fetus. In vitro functional experiments, including western-blotting and luciferase transactivation assay, were performed to determine the pathogenicity of the novel variant of TBX6. RESULTS: WES revealed the fetus harbored a compound heterozygous variant of c.338_340del (p.Ile113del) and the common hypomorphic risk haplotype of the TBX6 gene. In vitro functional study showed the p.Ile113del variant had no impact on TBX6 expression, but almost led to complete loss of its transcriptional activity. In addition, we identified a 1.85 Mb deletion on 17q12 region in the fetus and the mother. Though there is currently no clinical phenotype associated with this copy number variation in the fetus, it can explain multiple renal cysts in the pregnant woman. CONCLUSIONS: This study is the first to report a Chinese fetus with a single amino acid deletion variant and a T-C-A haplotype of TBX6. The clinical heterogeneity of 17q12 microdeletion poses significant challenges for prenatal genetic counseling. Our results once again suggest the complexity of prenatal genetic diagnosis.
Assuntos
Cromossomos Humanos Par 17 , Haplótipos , Heterozigoto , Proteínas com Domínio T , Humanos , Proteínas com Domínio T/genética , Feminino , Cromossomos Humanos Par 17/genética , Gravidez , Adulto , Deleção Cromossômica , Sequenciamento do Exoma , Deleção de Sequência , Feto/anormalidades , Ultrassonografia Pré-NatalRESUMO
Background: Copy number variants (CNVs) contribute significantly to normal and pathogenic genomic variations. Chromosome 17q12 microdeletion is implicated in structural or functional kidney and urethral abnormalities, MODY5 (type 5 diabetes), and neurodevelopmental or neuropsychiatric disorders. Conversely, microduplication of 17q12, though rare, elevates the risk of epilepsy and mental retardation. Case Presentation: This study focuses on a 33-year-old woman (gravida 1, para 0) who underwent amniocentesis at 22 weeks gestation due to bilateral hyperechogenic kidneys observed on prenatal ultrasound. Results: Chromosomal microarray analysis (CMA) unveiled a 1.46-Mb microdeletion on chromosome 17q12 in the fetus, spanning positions 35,802,057 to 37,261,945 (hg19). Trio whole-exome sequencing (WES) revealed 17q12 microdeletion in the fetus and 17q12 microduplication in the father. Notably, at the 3-year follow-up, the baby exhibited a normal phenotype. Conclusions: This research provides a comprehensive description of the phenotype in a rare family featuring 17q12 microdeletion and microduplication. Employing a combination of karyotype analysis, CMA, WES, prenatal ultrasound, and genetic counseling proves helpful in the prenatal diagnosis of chromosomal microdeletions/microduplications.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 17 , Diagnóstico Pré-Natal , Humanos , Feminino , Cromossomos Humanos Par 17/genética , Adulto , Gravidez , Diagnóstico Pré-Natal/métodos , Fenótipo , Análise Citogenética , Duplicação Cromossômica/genética , Ultrassonografia Pré-NatalRESUMO
Duchenne and Becker muscular dystrophies, caused by pathogenic variants in DMD, are the most common inherited neuromuscular conditions in childhood. These diseases follow an X-linked recessive inheritance pattern, and mainly males are affected. The most prevalent pathogenic variants in the DMD gene are copy number variants (CNVs), and most patients achieve their genetic diagnosis through Multiplex Ligation-dependent Probe Amplification (MLPA) or exome sequencing. Here, we investigated a female patient presenting with muscular dystrophy who remained genetically undiagnosed after MLPA and exome sequencing. RNA sequencing (RNAseq) from the patient's muscle biopsy identified an 85% reduction in DMD expression compared to 116 muscle samples included in the cohort. A de novo balanced translocation between chromosome 17 and the X chromosome (t(X;17)(p21.1;q23.2)) disrupting the DMD and BCAS3 genes was identified through trio whole genome sequencing (WGS). The combined analysis of RNAseq and WGS played a crucial role in the detection and characterisation of the disease-causing variant in this patient, who had been undiagnosed for over two decades. This case illustrates the diagnostic odyssey of female DMD patients with complex structural variants that are not detected by current panel or exome sequencing analysis.
Assuntos
Cromossomos Humanos X , Distrofina , Genômica , Distrofia Muscular de Duchenne , Translocação Genética , Humanos , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/diagnóstico , Feminino , Distrofina/genética , Cromossomos Humanos X/genética , Genômica/métodos , Variações do Número de Cópias de DNA , Sequenciamento do Exoma , Transcriptoma/genética , Cromossomos Humanos Par 17/genéticaRESUMO
Survival of Medulloblastoma (MB) depends on various factors, including the gene expression profiles of MB tumor tissues. In this study, we identified 967 MB survival-related genes (SRGs) using a gene expression dataset and the Cox proportional hazards regression model. Notably, the SRGs were over-represented on chromosomes 6 and 17, known for the abnormalities monosomy 6 and isochromosome 17 in MB. The most significant SRG was HMGA1 (high mobility group AT-hook 1) on chromosome 6, which is a known oncogene and a histone H1 competitor. High expression of HMGA1 was associated with worse survival, primarily in the Group 3γ subtype. The high expression of HMGA1 was unrelated to any known somatic copy number alteration. Most SRGs on chromosome 17p were associated with low expression in Group 4ß, the MB subtype, with 93% deletion of 17p and 98% copy gain of 17q. GO enrichment analysis showed that both chromosomes 6 and 17 included SRGs related to telomere maintenance and provided a rationale for testing telomerase inhibitors in Group 3 MBs. We conclude that HMGA1, along with other SRGs on chromosomes 6 and 17, warrant further investigation as potential therapeutic targets in selected subgroups or subtypes of MB.
Assuntos
Cromossomos Humanos Par 17 , Cromossomos Humanos Par 6 , Meduloblastoma , Humanos , Meduloblastoma/genética , Meduloblastoma/mortalidade , Meduloblastoma/patologia , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 6/genética , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/mortalidade , Neoplasias Cerebelares/patologia , Regulação Neoplásica da Expressão Gênica , Variações do Número de Cópias de DNA , Proteína HMGA1a/genética , Proteína HMGA1a/metabolismo , Feminino , Perfilação da Expressão GênicaRESUMO
Despite tremendous improvements in the outcome of patients with multiple myeloma in the past decade, high-risk patients have not benefited from the approval of novel drugs. The most important prognostic factor is the loss of parts of the short arm of chromosome 17, known as deletion 17p (del(17p)). A recent publication (on a small number of patients) suggested that these patients are at very high-risk only if del(17p) is associated with TP53 mutations, the so-called "double-hit" population. To validate this finding, we designed a much larger study on 121 patients presenting del(17p) in > 55% of their plasma cells, and homogeneously treated by an intensive approach. For these 121 patients, we performed deep next generation sequencing targeted on TP53. The outcome was then compared with a large control population (2505 patients lacking del(17p)). Our results confirmed that the "double hit" situation is the worst (median survival = 36 months), but that del(17p) alone also confers a poor outcome compared with the control cohort (median survival = 52.8 months vs 152.2 months, respectively). In conclusion, our study clearly confirms the extremely poor outcome of patients displaying "double hit," but also that del(17p) alone is still a very high-risk feature, confirming its value as a prognostic indicator for poor outcome.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Mieloma Múltiplo/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Mutação , Prognóstico , Adulto JovemRESUMO
Deletion of 17p13.3 has varying degrees of severity on brain development based on precise location and size of the deletion. The most severe phenotype is Miller-Dieker syndrome (MDS) which is characterized by lissencephaly, dysmorphic facial features, growth failure, developmental disability, and often early death. Haploinsufficiency of PAFAH1B1 is responsible for the characteristic lissencephaly in MDS. The precise role of YWHAE haploinsufficiency in MDS is unclear. Case reports are beginning to elucidate the phenotypes of individuals with 17p13.3 deletions that have deletion of YWHAE but do not include deletion of PAFAH1B1. Through our clinical genetics practice, we identified four individuals with 17p13.3 deletion that include YWHAE but not PAFAH1B1. These patients have a similar phenotype of dysmorphic facial features, developmental delay, and leukoencephalopathy. In a review of the literature, we identified 19 patients with 17p13.3 microdeletion sparing PAFAH1B1 but deleting YWHAE. Haploinsufficiency of YWHAE is associated with brain abnormalities including cystic changes. These individuals have high frequency of epilepsy, intellectual disability, and dysmorphic facial features including prominent forehead, epicanthal folds, and broad nasal root. We conclude that deletion of 17p13.3 excluding PAFAH1B1 but including YWHAE is associated with a consistent phenotype and should be considered a distinct condition from MDS.
Assuntos
Lissencefalias Clássicas e Heterotopias Subcorticais em Banda , Deficiência Intelectual , Lisencefalia , Humanos , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/genética , Deleção Cromossômica , Lisencefalia/genética , Fenótipo , Deficiência Intelectual/genética , Cromossomos Humanos Par 17/genética , Encéfalo , Proteínas 14-3-3/genéticaRESUMO
Koolen-de Vries syndrome (KdVS) is a rare multisystemic disorder caused by a microdeletion on chromosome 17q21.31 including KANSL1 gene or intragenic pathogenic variants in KANSL1 gene. Here, we describe the clinical and genetic spectrum of eight Turkish children with KdVS due to a de novo 17q21.31 deletion, and report on several rare/new conditions. Eight patients from unrelated families aged between 17 months and 19 years enrolled in this study. All patients evaluated by a clinical geneticist, and the clinical diagnosis were confirmed by molecular karyotyping. KdVS patients had some common distinctive facial features. All patients had neuromotor retardation, and speech and language delay. Epilepsy, structural brain anomalies, ocular, ectodermal, and musculoskeletal findings, and friendly personality were remarkable in more than half of the patients. Hypertension, hypothyroidism, celiac disease, and postaxial polydactyly were among the rare/new conditions. Our study contributes to the clinical spectrum of patients with KdVS, while also provide a review by comparing them with previous cohort studies.
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Anormalidades Múltiplas , Deficiência Intelectual , Humanos , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/genética , Deleção Cromossômica , Doenças Raras/genética , Fenótipo , Cromossomos Humanos Par 17/genéticaRESUMO
BACKGROUND: Koolen-de Vries syndrome (KdVS) is a multisystem neurodevelopmental disorder caused by 17q21.31 deletions or mutations in KANSL1. It was mainly described in children. METHODS: A retrospective study on 9 subjects aged 19-45 years and revision of 18 literature patients, with the purpose to get insights into the phenotypic evolution with time, and into the clinical manifestations in adulthood. RESULTS: Seven patients had a 17q21.31 deletion and two a point mutation in KANSL1. All had intellectual disability, which was mild in five (56%) and moderate in four (44%). Epilepsy was diagnosed in four subjects (44%), with onset from 1 to 7 years and full remission before 9 years in 3/4 patients. Scoliosis affected seven individuals (77.7%) and it was substantially stable with age in 5/7 patients, allowing for simple daily activities. Two subjects had severely progressive scoliosis, which was surgically corrected. Overweight or true obesity did occur after puberty in six patients (67%). Behaviour abnormalities were recorded in six patients (67%). The facial phenotype slightly evolved with time to include thick eyebrows, elongated nose and pronounced pointed chin. Despite behaviour abnormalities, happy disposition and sociable attitudes were common. Half of patients had fluent language and were good at writing and reading. Rich language, although limited to single words or short sentences, and very limited or absent skills in writing and reading were observed in the remaining patients. Autonomy in daily activities and personal care was usually limited. CONCLUSIONS: Distinctive features in adult KdVS subjects include intellectual disability, overweight/obesity, behaviour abnormalities with preserved social interest, ability in language, slight worsening of the facial phenotype and no seizures.
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Anormalidades Múltiplas/patologia , Deficiência Intelectual/patologia , Proteínas Nucleares/genética , Anormalidades Múltiplas/genética , Adulto , Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Feminino , Humanos , Deficiência Intelectual/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Estudos Retrospectivos , Adulto JovemRESUMO
The diagnosis of acute promyelocytic leukemia (APL) relies on the identification of PML::RARA fusion. While the majority of APL cases harbor a typical t(15;17)(q24;q21), atypical genetic mechanisms leading to the oncogenic PML::RARA fusion have been reported yet their frequency and scope remain poorly characterized. We assessed the genetic findings of 831 cases with APL investigated with concurrent chromosome banding analysis and dual-color dual-fusion fluorescence in situ hybridization (D-FISH) analysis at our institution over an 18.5-year timeframe. Seven hundred twenty-three (87%) cases had a typical balanced t(15;17) with both testing modalities. Atypical karyotypic results including complex translocations, unbalanced rearrangements and insertional events occurred in 50 (6%) cases, while 6 (0.7%) cases were cryptic by conventional chromosome studies despite PML::RARA fusion by D-FISH evaluation. Atypical FISH patterns were observed in 48 (6%) cases despite apparently balanced t(15;17) on chromosome banding analysis. Two hundred fifty (30%) cases displayed additional chromosome abnormalities of which trisomy/tetrasomy 8 (37%), del(7q)/add(7q) (12%), and del(9q) (7%) were most frequent. Complex and very complex karyotypes were observed in 81 (10%) and 34 (4%) cases, respectively. In addition, 4 (0.5%) cases presented as an apparently doubled, near-tetraploid stemline clone. This report provides the largest appraisal of cytogenetic findings in APL with conventional chromosome and PML::RARA D-FISH analysis. By characterizing the frequency and breadth of typical and atypical results through the lens of these cytogenetic testing modalities, this study serves as a pragmatic source of information for those involved in the investigation of APL in both the clinical and research laboratory settings.
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Leucemia Promielocítica Aguda , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 8 , Humanos , Hibridização in Situ Fluorescente , Leucemia Promielocítica Aguda/genética , Proteínas de Fusão Oncogênica/genética , Estudos Retrospectivos , Translocação Genética , TrissomiaRESUMO
OBJECTIVE: To carry out optical genome mapping (OGM) for a Chinese pedigree with a rare paracentric reverse insertion of chromosome 17. METHODS: A high-risk pregnant woman identified at the Prenatal Diagnosis Center of Hangzhou Women's Hospital in October 2021 and her family members were selected as the study subjects. Chromosome G banding analysis, fluorescence in situ hybridization (FISH), single nucleotide polymorphism array (SNP array) and OGM were applied to verify the balanced structural abnormality of chromosome 17 in the pedigree. RESULTS: Chromosomal karyotyping analysis and SNP array assay have identified a duplication of 17q23q25 in the fetus. Karyotyping analysis of the pregnant woman showed that the structure of chromosome 17 was abnormal, whilst SNP array has detected no abnormality. OGM revealed that the woman has carried a paracentric reverse insertion, which was confirmed by FISH. The karyotype of her husband was normal. CONCLUSION: The duplication of 17q23q25 in the fetus has derived from a paracentric reverse insertion of chromosome 17 in its mother. OGM has the advantage for delineating balanced chromosome structural abnormalities.