ABSTRACT
8q21.11 microdeletions encompassing the gene encoding transcription factor ZFHX4, have previously been associated by us with a syndromic form of intellectual disability, hypotonia, decreased balance and hearing loss. Here, we report on 57 individuals, 52 probands and 5 affected family members, with protein truncating variants (n=36), (micro)deletions (n=20) or an inversion (n=1) affecting ZFHX4 with variable developmental delay and intellectual disability, distinctive facial characteristics, morphological abnormalities of the central nervous system, behavioral alterations, short stature, hypotonia, and occasionally cleft palate and anterior segment dysgenesis. The phenotypes associated with 8q21.11 microdeletions and ZFHX4 intragenic loss-of-function variants largely overlap, identifying ZFHX4 as the main driver for the microdeletion syndrome, although leukocyte-derived DNA shows a mild common methylation profile for (micro)deletions only. We identify ZFHX4 as a transcription factor that is increasingly expressed during human brain development and neuronal differentiation. Furthermore, ZFHX4 interacting factors identified via IP-MS in neural progenitor cells, suggest an important role for ZFHX4 in cellular and developmental pathways, especially during histone modifications, cytosolic transport and development. Additionally, using CUT&RUN, we observed that ZFHX4 binds with the promoter regions of genes with crucial roles in embryonic, neuron and axon development. Since loss-of-function variants in ZFHX4 are found with consistent dysmorphic facial features, we investigated whether the disruption of zfhx4 causes craniofacial abnormalities in zebrafish. First-generation (F0) zfhx4 crispant zebrafish, (mosaic) mutant for zfhx4 loss-of-function variants, have significantly shorter Meckel's cartilages and smaller ethmoid plates compared to control zebrafish. Furthermore, behavioral assays show a decreased movement frequency in the zfhx4 crispant zebrafish in comparison with control zebrafish larvae. Although further research is needed, our in vivo work suggests a role for zfhx4 in facial skeleton patterning, palatal development and behavior.
ABSTRACT
Non-small cell lung cancer (NSCLC) is known for high relapse rates despite resection in early stages. Here, we present the results of a phase I clinical trial in which a dendritic cell (DC) vaccine targeting patient-individual neoantigens is evaluated in patients with resected NSCLC. Vaccine manufacturing is feasible in six of 10 enrolled patients. Toxicity is limited to grade 1-2 adverse events. Systemic T cell responses are observed in five out of six vaccinated patients, with T cell responses remaining detectable up to 19 months post vaccination. Single-cell analysis indicates that the responsive T cell population is polyclonal and exhibits the near-entire spectrum of T cell differentiation states, including a naive-like state, but excluding exhausted cell states. Three of six vaccinated patients experience disease recurrence during the follow-up period of 2 years. Collectively, these data support the feasibility, safety, and immunogenicity of this treatment in resected NSCLC.
Subject(s)
Antigens, Neoplasm , Cancer Vaccines , Carcinoma, Non-Small-Cell Lung , Cell Differentiation , Dendritic Cells , Lung Neoplasms , T-Lymphocytes , Vaccination , Humans , Dendritic Cells/immunology , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Cancer Vaccines/immunology , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/therapy , Male , Female , Middle Aged , Antigens, Neoplasm/immunology , Cell Differentiation/immunology , Aged , T-Lymphocytes/immunologyABSTRACT
STUDY QUESTION: Is pronuclear transfer (PNT) capable of restoring embryo developmental arrest caused by cytoplasmic inferiority of in vitro-grown (IVG) mouse oocytes? SUMMARY ANSWER: PNT to in vivo matured cytoplasm significantly improved embryo development of IVG mouse oocytes, leading to living, fertile offspring. WHAT IS KNOWN ALREADY: In vitro follicle culture has been considered as a fertility preservation option for cancer patients. Studies describing the culture of human follicles remain scarce, owing to low availability of tissue. Mouse models have extensively been used to study and optimize follicle culture. Although important achievements have been accomplished, including the production of healthy offspring in mice, IVG oocytes are of inferior quality when compared to in vivo-grown oocytes, likely because of cytoplasmic incompetence. STUDY DESIGN SIZE DURATION: The study was carried out from September 2020 to February 2022. In total, 120 15-day-old B6D2 mice were used to perform secondary follicle culture and assess the quality of IVG oocytes. In vivo-grown control oocytes were obtained from 85 8- to 12-week-old B6D2 mice, following ovarian stimulation. For sperm collection, four B6D2 males between 10 and 14 weeks old were used. For embryo transfer, 14 8- to 12-week-old CD1 females served as surrogate mothers and 10 CD1 vasectomized males 10-24 weeks old were used to generate pseudo-pregnant females. Finally, for mating, four B6D2 female mice aged 8-10 weeks and two B6D2 male mice aged 10 weeks old were used to confirm the fertility of nuclear transfer (NT)-derived pups. PARTICIPANTS/MATERIALS SETTING METHODS: Secondary follicles from 15-day-old B6D2 mice were isolated from the ovaries and cultured for 9 days, before a maturation stimulus was given. Following 16-18 h of maturation, oocytes were collected and evaluated on maturation rate, oocyte diameter, activation rate, spindle morphology, calcium-releasing ability, and mitochondrial membrane potential. For every experiment, in vivo-grown oocytes were used as a control for comparison. When cytoplasmic immaturity and poor embryo development were confirmed in IVG oocytes, PNT was performed. For this, the pronuclei from IVG oocytes, created following parthenogenetic activation and IVF, were transferred to the cytoplasm of fertilized, in vivo-grown oocytes. Genetic analysis and embryo transfer of the generated embryos were implemented to confirm the safety of the technique. MAIN RESULTS AND THE ROLE OF CHANCE: Following 9 days of follicle culture, 703 oocytes were collected, of which 76% showed maturation to the metaphase II stage. Oocyte diameters were significantly lower in IVG oocytes, measuring 67.4 µm versus 73.1 µm in controls (P < 0.001). Spindle morphology did not differ significantly between IVG and control oocytes, but calcium-releasing ability was compromised in the IVG group. An average calcium release of 1.62 arbitrary units was observed in IVG oocytes, significantly lower than 5.74 in control oocytes (P < 0.001). Finally, mitochondrial membrane potential was inferior in IVG compared to the control group, reaching an average value of 0.95 versus 2.27 (P < 0.001). Developmental potential of IVG oocytes was assessed following parthenogenetic activation with strontium chloride (SrCl2). Only 59.4% of IVG oocytes cleaved to two cells and 36.3% reached the blastocyst stage, significantly lower than 89.5% and 88.2% in control oocytes, respectively (P < 0.001 and 0.001). Both PNT and spindle transfer (ST) were explored in pilot experiments with parthenogenetically activated oocytes, as a means to overcome poor embryo development. After the added value of NT was confirmed, we continued with the generation of biparental embryos by PNT. For this purpose, IVG and control oocytes first underwent IVF. Only 15.5% of IVG oocytes were normally fertilized, in contrast to 45.5% in controls (P < 0.001), with resulting failure of blastocyst formation in the IVG group (0 versus 86.2%, P < 0.001). When the pronuclei of IVG zygotes were transferred to the cytoplasm of control zygotes, the blastocyst rate was restored to 86.9%, a similar level as the control. Genetic analysis of PNT embryos revealed a normal chromosomal profile, to a rate of 80%. Finally, the generation of living, fertile offspring from PNT was possible following embryo transfer to surrogate mothers. LARGE-SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: Genetic profiles of analysed embryos from PNT originate from groups that are too small to draw concrete conclusions, whilst ST, which would be the preferred NT approach, could not be used for the generation of biparental embryos owing to technical limitations. Even though promising, the use of PNT should be considered as experimental. Furthermore, results were acquired in a mouse model, so validation of the technique in human IVG oocytes needs to be performed to evaluate the clinical relevance of the technology. The genetic profiles from IVG oocytes, which would be the ultimate characterization for chromosomal abnormalities, were not analysed owing to limitations in the reliable analysis of single cells. WIDER IMPLICATIONS OF THE FINDINGS: PNT has the ability to overcome the poor cytoplasmic quality of IVG mouse oocytes. Considering the low maturation efficiency of human IVG oocytes and potential detrimental effects following long-term in vitro culture, NT could be applied to rescue embryo development and could lead to an increased availability of good quality embryos for transfer. STUDY FUNDING/COMPETING INTERESTS: A.C. is a holder of FWO (Fonds voor Wetenschappelijk Onderzoek) grants (1S80220N and 1S80222N). B.H. and A.V.S. have been awarded with a special BOF (Bijzonder Onderzoeksfonds), GOA (Geconcerteerde onderzoeksacties) 2018000504 (GOA030-18 BOF) funding. B.H. has been receiving unrestricted educational funding from Ferring Pharmaceuticals (Aalst, Belgium). The authors declare that they have no conflict of interest.
ABSTRACT
Neurodevelopmental disorders (NDDs) result from impaired development and functioning of the brain. Here, we identify loss-of-function (LoF) variation in ZFHX3 as a cause for syndromic intellectual disability (ID). ZFHX3 is a zinc-finger homeodomain transcription factor involved in various biological processes, including cell differentiation and tumorigenesis. We describe 42 individuals with protein-truncating variants (PTVs) or (partial) deletions of ZFHX3, exhibiting variable intellectual disability and autism spectrum disorder, recurrent facial features, relative short stature, brachydactyly, and, rarely, cleft palate. ZFHX3 LoF associates with a specific methylation profile in whole blood extracted DNA. Nuclear abundance of ZFHX3 increases during human brain development and neuronal differentiation. ZFHX3 was found to interact with the chromatin remodeling BRG1/Brm-associated factor complex and the cleavage and polyadenylation complex, suggesting a function in chromatin remodeling and mRNA processing. Furthermore, ChIP-seq for ZFHX3 revealed that it predominantly binds promoters of genes involved in nervous system development. We conclude that loss-of-function variants in ZFHX3 are a cause of syndromic ID associating with a specific DNA methylation profile.
Subject(s)
Autism Spectrum Disorder , Intellectual Disability , Neurodevelopmental Disorders , Humans , Intellectual Disability/genetics , Intellectual Disability/complications , Haploinsufficiency/genetics , Neurodevelopmental Disorders/genetics , Brain/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolismABSTRACT
STUDY QUESTION: Does the diagnosis of mosaicism affect ploidy rates across different providers offering preimplantation genetic testing for aneuploidies (PGT-A)? SUMMARY ANSWER: Our analysis of 36 395 blastocyst biopsies across eight genetic testing laboratories revealed that euploidy rates were significantly higher in providers reporting low rates of mosaicism. WHAT IS KNOWN ALREADY: Diagnoses consistent with chromosomal mosaicism have emerged as a third category of possible embryo ploidy outcomes following PGT-A. However, in the era of mosaicism, embryo selection has become increasingly complex. Biological, technical, analytical, and clinical complexities in interpreting such results have led to substantial variability in mosaicism rates across PGT-A providers and clinics. Critically, it remains unknown whether these differences impact the number of euploid embryos available for transfer. Ultimately, this may significantly affect clinical outcomes, with important implications for PGT-A patients. STUDY DESIGN, SIZE, DURATION: In this international, multicenter cohort study, we reviewed 36 395 consecutive PGT-A results, obtained from 10 035 patients across 11 867 treatment cycles, conducted between October 2015 and October 2021. A total of 17 IVF centers, across eight PGT-A providers, five countries and three continents participated in the study. All blastocysts were tested using trophectoderm biopsy and next-generation sequencing. Both autologous and donation cycles were assessed. Cycles using preimplantation genetic testing for structural rearrangements were excluded from the analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: The PGT-A providers were randomly categorized (A to H). Providers B, C, D, E, F, G, and H all reported mosaicism, whereas Provider A reported embryos as either euploid or aneuploid. Ploidy rates were analyzed using multilevel mixed linear regression. Analyses were adjusted for maternal age, paternal age, oocyte source, number of embryos biopsied, day of biopsy, and PGT-A provider, as appropriate. We compared associations between genetic testing providers and PGT-A outcomes, including the number of chromosomally normal (euploid) embryos determined to be suitable for transfer. MAIN RESULTS AND THE ROLE OF CHANCE: The mean maternal age (±SD) across all providers was 36.2 (±5.2). Our findings reveal a strong association between PGT-A provider and the diagnosis of euploidy and mosaicism. Amongst the seven providers that reported mosaicism, the rates varied from 3.1% to 25.0%. After adjusting for confounders, we observed a significant difference in the likelihood of diagnosing mosaicism across providers (P < 0.001), ranging from 6.5% (95% CI: 5.2-7.4%) for Provider B to 35.6% (95% CI: 32.6-38.7%) for Provider E. Notably, adjusted euploidy rates were highest for providers that reported the lowest rates of mosaicism (Provider B: euploidy, 55.7% (95% CI: 54.1-57.4%), mosaicism, 6.5% (95% CI: 5.2-7.4%); Provider H: euploidy, 44.5% (95% CI: 43.6-45.4%), mosaicism, 9.9% (95% CI: 9.2-10.6%)); and Provider D: euploidy, 43.8% (95% CI: 39.2-48.4%), mosaicism, 11.0% (95% CI: 7.5-14.5%)). Moreover, the overall chance of having at least one euploid blastocyst available for transfer was significantly higher when mosaicism was not reported, when we compared Provider A to all other providers (OR = 1.30, 95% CI: 1.13-1.50). Differences in diagnosing and interpreting mosaic results across PGT-A laboratories raise further concerns regarding the accuracy and relevance of mosaicism predictions. While we confirmed equivalent clinical outcomes following the transfer of mosaic and euploid blastocysts, we found that a significant proportion of mosaic embryos are not used for IVF treatment. LIMITATIONS, REASONS FOR CAUTION: Due to the retrospective nature of the study, associations can be ascertained, however, causality cannot be established. Certain parameters such as blastocyst grade were not available in the dataset. Furthermore, certain platform-related and clinic-specific factors may not be readily quantifiable or explicitly captured in our dataset. As such, a full elucidation of all potential confounders accounting for variability may not be possible. WIDER IMPLICATIONS OF THE FINDINGS: Our findings highlight the strong need for standardization and quality assurance in the industry. The decision not to transfer mosaic embryos may ultimately reduce the chance of success of a PGT-A cycle by limiting the pool of available embryos. Until we can be certain that mosaic diagnoses accurately reflect biological variability, reporting mosaicism warrants utmost caution. A prudent approach is imperative, as it may determine the difference between success or failure for some patients. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Torres Quevedo Grant, awarded to M.P. (PTQ2019-010494) by the Spanish State Research Agency, Ministry of Science and Innovation, Spain. M.P., L.B., A.R.L., A.L.R.d.C.L., N.P.P., M.P., D.S., F.A., A.P., B.M., L.D., F.V.M., D.S., M.R., E.P.d.l.B., A.R., and R.V. have no competing interests to declare. B.L., R.M., and J.A.O. are full time employees of IB Biotech, the genetics company of the Instituto Bernabeu group, which performs preimplantation genetic testing. M.G. is a full time employee of Novagen, the genetics company of Cegyr, which performs preimplantation genetic testing. TRIAL REGISTRATION NUMBER: N/A.
Subject(s)
Mosaicism , Preimplantation Diagnosis , Female , Humans , Pregnancy , Aneuploidy , Bias, Implicit , Blastocyst/pathology , Cohort Studies , Genetic Testing/methods , Preimplantation Diagnosis/methods , Retrospective Studies , AdultABSTRACT
Maternally inherited 15q11-q13 duplications are generally found to cause more severe neurodevelopmental anomalies compared to paternally inherited duplications. However, this assessment is mainly inferred from the study of patient populations, causing an ascertainment bias towards patients at the more severe end of the phenotypic spectrum. Here, we analyze the low coverage genome-wide cell-free DNA sequencing data obtained from pregnant women during non-invasive prenatal screening (NIPS). We detect 23 15q11-q13 duplications in 333,187 pregnant women (0.0069%), with an approximately equal distribution between maternal and paternal duplications. Maternally inherited duplications are always associated with a clinical phenotype (ranging from learning difficulties to intellectual impairment, epilepsy and psychiatric disorders), while paternal duplications are normal or associated with milder phenotypes (mild learning difficulties and dyslexia). This data corroborates the difference in impact between paternally and maternally inherited 15q11-q13 duplications, contributing to the improvement of genetic counselling. We recommend reporting 15q11-q13 duplications identified during genome-wide NIPS with appropriate genetic counselling for these pregnant women in the interest of both mothers and future children.
Subject(s)
Mothers , Paternal Inheritance , Pregnancy , Child , Humans , Female , Alleles , Phenotype , Chromosomes, Human, Pair 15/geneticsABSTRACT
Human germline gene correction by targeted nucleases holds great promise for reducing mutation transmission. However, recent studies have reported concerning observations in CRISPR-Cas9-targeted human embryos, including mosaicism and loss of heterozygosity (LOH). The latter has been associated with either gene conversion or (partial) chromosome loss events. In this study, we aimed to correct a heterozygous basepair substitution in PLCZ1, related to infertility. In 36% of the targeted embryos that originated from mutant sperm, only wild-type alleles were observed. By performing genome-wide double-digest restriction site-associated DNA sequencing, integrity of the targeted chromosome (i.e., no deletions larger than 3 Mb or chromosome loss) was confirmed in all seven targeted GENType-analyzed embryos (mutant editing and absence of mutation), while short-range LOH events (shorter than 10 Mb) were clearly observed by single-nucleotide polymorphism assessment in two of these embryos. These results fuel the currently ongoing discussion on double-strand break repair in early human embryos, making a case for the occurrence of gene conversion events or partial template-based homology-directed repair.
Subject(s)
CRISPR-Cas Systems , Gene Editing , Humans , Male , Gene Editing/methods , Semen , Mutation , Alleles , ChromosomesABSTRACT
Neurodevelopmental disorders (NDDs) result from impaired development and functioning of the brain. Here, we identify loss-of-function variation in ZFHX3 as a novel cause for syndromic intellectual disability (ID). ZFHX3, previously known as ATBF1, is a zinc-finger homeodomain transcription factor involved in multiple biological processes including cell differentiation and tumorigenesis. Through international collaboration, we collected clinical and morphometric data (Face2Gene) of 41 individuals with protein truncating variants (PTVs) or (partial) deletions of ZFHX3 . We used data mining, RNA and protein analysis to identify the subcellular localization and spatiotemporal expression of ZFHX3 in multiple in vitro models. We identified the DNA targets of ZFHX3 using ChIP seq. Immunoprecipitation followed by mass spectrometry indicated potential binding partners of endogenous ZFHX3 in neural stem cells that were subsequently confirmed by reversed co-immunoprecipitation and western blot. We evaluated a DNA methylation profile associated with ZFHX3 haploinsufficiency using DNA methylation analysis on whole blood extracted DNA of six individuals with ZFHX3 PTVs and four with a (partial) deletion of ZFHX3 . A reversed genetic approach characterized the ZFHX3 orthologue in Drosophila melanogaster . Loss-of-function variation of ZFHX3 consistently associates with (mild) ID and/or behavioural problems, postnatal growth retardation, feeding difficulties, and recognizable facial characteristics, including the rare occurrence of cleft palate. Nuclear abundance of ZFHX3 increases during human brain development and neuronal differentiation in neural stem cells and SH-SY5Y cells, ZFHX3 interacts with the chromatin remodelling BRG1/Brm-associated factor complex and the cleavage and polyadenylation complex. In line with a role for chromatin remodelling, ZFHX3 haploinsufficiency associates with a specific DNA methylation profile in leukocyte-derived DNA. The target genes of ZFHX3 are implicated in neuron and axon development. In Drosophila melanogaster , z fh2, considered to be the ZFHX3 orthologue, is expressed in the third instar larval brain. Ubiquitous and neuron-specific knockdown of zfh2 results in adult lethality underscoring a key role for zfh2 in development and neurodevelopment. Interestingly, ectopic expression of zfh2 as well as ZFHX3 in the developing wing disc results in a thoracic cleft phenotype. Collectively, our data shows that loss-of-function variants in ZFHX3 are a cause of syndromic ID, that associates with a specific DNA methylation profile. Furthermore, we show that ZFHX3 participates in chromatin remodelling and mRNA processing.
ABSTRACT
In the human thymus, a CD10+ PD-1+ TCRαß+ differentiation pathway diverges from the conventional single positive T cell lineages at the early double-positive stage. Here, we identify the progeny of this unconventional lineage in antigen-inexperienced blood. These unconventional T cells (UTCs) in thymus and blood share a transcriptomic profile, characterized by hallmark transcription factors (i.e., ZNF683 and IKZF2), and a polyclonal TCR repertoire with autoreactive features, exhibiting a bias toward early TCRα chain rearrangements. Single-cell RNA sequencing confirms a common developmental trajectory between the thymic and blood UTCs and clearly delineates this unconventional lineage in blood. Besides MME+ recent thymic emigrants, effector-like clusters are identified in this heterogeneous lineage. Expression of Helios and KIR and a decreased CD8ß expression are characteristics of this lineage. This UTC lineage could be identified in adult blood and intestinal tissues. In summary, our data provide a comprehensive characterization of the polyclonal unconventional lineage in antigen-inexperienced blood and identify the adult progeny.
Subject(s)
Receptors, Antigen, T-Cell, alpha-beta , T-Lymphocytes , Adult , Humans , Cell Lineage , T-Lymphocytes/metabolism , Receptors, Antigen, T-Cell, alpha-beta/genetics , Receptors, Antigen, T-Cell, alpha-beta/metabolism , Cell Differentiation , Thymus GlandABSTRACT
Marfan syndrome is an autosomal dominant genetic disorder resulting from pathogenic variants in FBN1 gene. FBN1 encodes for fibrillin-1, an important extracellular matrix protein. Impaired fibrillin-1 affects multiple organ systems, including the cardiovascular system. We generated an iPSC line carrying a heterozygous variant c.7754 T > C (p.Ile2585Thr, missense) in FBN1 from a patient with Marfan syndrome. Also, an isogenic control is generated, where the pathogenic variant is repaired using CRISPR-Cas9. This isogenic pair provides a valuable resource for in vitro disease modelling.
Subject(s)
Induced Pluripotent Stem Cells , Marfan Syndrome , Humans , CRISPR-Cas Systems , Fibrillin-1/genetics , Heterozygote , Induced Pluripotent Stem Cells/metabolism , Marfan Syndrome/genetics , MutationABSTRACT
Point mutations and structural variants that directly disrupt the coding sequence of MEF2C have been associated with a spectrum of neurodevelopmental disorders (NDDs). However, the impact of MEF2C haploinsufficiency on neurodevelopmental pathways and synaptic processes is not well understood, nor are the complex mechanisms that govern its regulation. To explore the functional changes associated with structural variants that alter MEF2C expression and/or regulation, we generated an allelic series of 204 isogenic human induced pluripotent stem cell (hiPSC)-derived neural stem cells and glutamatergic induced neurons. These neuronal models harbored CRISPR-engineered mutations that involved direct deletion of MEF2C or deletion of the boundary points for topologically associating domains (TADs) and chromatin loops encompassing MEF2C. Systematic profiling of mutation-specific alterations, contrasted to unedited controls that were exposed to the same guide RNAs for each edit, revealed that deletion of MEF2C caused differential expression of genes associated with neurodevelopmental pathways and synaptic function. We also discovered significant reduction in synaptic activity measured by multielectrode arrays (MEAs) in neuronal cells. By contrast, we observed robust buffering against MEF2C regulatory disruption following deletion of a distal 5q14.3 TAD and loop boundary, whereas homozygous loss of a proximal loop boundary resulted in down-regulation of MEF2C expression and reduced electrophysiological activity on MEA that was comparable to direct gene disruption. Collectively, these studies highlight the considerable functional impact of MEF2C deletion in neuronal cells and systematically characterize the complex interactions that challenge a priori predictions of regulatory consequences from structural variants that disrupt three-dimensional genome organization.
Subject(s)
Induced Pluripotent Stem Cells , Neural Stem Cells , Humans , Genome , Haploinsufficiency , MEF2 Transcription Factors/genetics , Neurons , Transcription, GeneticABSTRACT
Dystroglycanopathies are a group of congenital muscular dystrophies (CMDs) that include a broad phenotypic spectrum ranging from late-onset limb-girdle muscular dystrophy to severe muscle-eye-brain disease, Walker-Warburg syndrome, and Fukuyama congenital muscular dystrophy. In addition to clinical heterogeneity, CMDs are characterized by genetic heterogeneity. To date, 18 genes have been associated with CMDs. One of them is B3GALNT2, which encodes the ß-1,3-N-acetylgalactosaminyltransferase 2 that glycosylates α-dystroglycan. In this study, using exome sequencing, we identify a homozygous frameshift variant in B3GALNT2 due to a mixed uniparental disomy of chromosome 1 in a 7-year-old girl with global developmental delay, severely delayed active language development, and autism spectrum disorder but without any symptoms of muscular dystrophy. In addition to this case, we also provide an overview of all previously reported cases, further expanding the phenotypic spectrum.
Subject(s)
Autism Spectrum Disorder , Muscular Dystrophies, Limb-Girdle , Muscular Dystrophies , N-Acetylgalactosaminyltransferases , Dystroglycans/genetics , Humans , Muscular Dystrophies/genetics , N-Acetylgalactosaminyltransferases/genetics , PhenotypeABSTRACT
Diagnosis of lung cancer requires histological examination of a tissue sample, which in turn requires an invasive procedure that cannot always be obtained. Circulating tumor DNA can be reliably detected in blood samples of advanced-stage lung cancer patients and might also be a minimally invasive alternative for early-stage lung cancer detection. We wanted to explore the potential of targeted deep sequencing as a test for the diagnosis of early-stage lung cancer in combination with imaging. Mutation detection on cell-free DNA from pretreatment plasma samples of 51 patients with operable non-small cell lung cancer was performed and results were compared with 12 control patients undergoing surgery for a non-malignant lung lesion. By using a variant allele frequency threshold of 1%, somatic variants were detected in 23.5% of patients with a median variant allele fraction of 3.65%. By using this threshold, we could almost perfectly discriminate early-stage lung cancer patients from controls. Our study results are discussed in the light of those from other studies. Notwithstanding the potential of today's techniques for the use of liquid biopsy-based cell-free DNA analysis, sensitivity of this application for early-stage lung cancer detection is currently limited by a biological background of somatic variants with low variant allele fraction.
ABSTRACT
Despite the considerable impact of stroke on both the individual and on society, a neuroprotective therapy for stroke patients is missing. This is partially due to the current lack of a physiologically relevant human in vitro stroke model. To address this problem, we have developed a luminescent human iPSC-derived neurospheroid model that enables real-time read-out of neural viability after ischemia-like conditions. We subjected 1- and 4-week-old neurospheroids, generated from iPSC-derived neural stem cells, to 6 h of oxygen-glucose deprivation (OGD) and measured neurospheroid luminescence. For both, we detected a decrease in luminescent signal due to ensuing neurotoxicity, as confirmed by conventional LDH assay and flow cytometric viability analysis. Remarkably, 1-week-old, but not 4-week-old neurospheroids recovered from OGD-induced injury, as evidenced by their reduced but overall increasing luminescence over time. This underscores the need for more mature neurospheroids, more faithfully recapitulating the in vivo situation. Furthermore, treatment of oxygen- and glucose-deprived neurospheroids with the pan-caspase inhibitor Z-VAD-FMK did not increase overall neural survival, despite its successful attenuation of apoptosis, in a human-based 3D environment. Nevertheless, owing to its three-dimensional organization and real-time viability reporting potential, the luminescent neurospheroids may become readily adopted in high-throughput screens aimed at identification of new therapeutic agents to treat acute ischemic stroke patients.
Subject(s)
Induced Pluripotent Stem Cells , Ischemic Stroke , Stroke , Apoptosis , Cell Survival/physiology , Glucose , Humans , Luminescence , Oxygen/adverse effectsABSTRACT
Background: Breast cancer and hematological cancers are the most commonly diagnosed malignancies during pregnancy. This case report is the first to describe the ultimate challenge to preserve a pregnancy while the expectant mother is diagnosed and treated simultaneously for two concurrent primary malignancies, a stage IIA Hodgkin lymphoma and pT2N0(Sn) breast cancer. Clinical case: A 36-year-old pregnant primigravida underwent a routine non-invasive prenatal test at 14â¯weeks and 4â¯days of gestation. Genome-wide sequencing was used and revealed an aberrant DNA/chromosome copy number profile among which a strong 2p-gain, possibly related to a maternal malignancy. Physical examination showed an enlarged cervical lymph node and ultrasound guided biopsy confirmed the diagnosis of a nodular sclerosing classical Hodgkin lymphoma subsequently staged as an early stage, unfavorable (IIA) Hodgkin lymphoma. Whole body magnetic resonance imaging for further staging also indicated a suspicious nodule in the right breast. Further investigation resulted in the concurrent diagnosis of a pT2N0(Sn) invasive ductal adenocarcinoma. Patient underwent a mastectomy with sentinel lymph node biopsy at 15â¯weeks and 5â¯days of gestation, followed by 4-weekly chemotherapy administration, consisting of doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD). Pregnancy went further relatively uncomplicated and fetal assessment was reassuring during pregnancy. Due to fever of unknown origin and preterm labor, a cesarean section was performed on a gestational age of 35â¯weeks and 4â¯days. Oncological treatment was completed after delivery with involved-field radiation therapy for the Hodgkin lymphoma. Completion of systemic treatment for breast cancer consisted of docetaxel/cyclophosphamide chemotherapy, and anti-hormonal treatment in the form of ovarian function suppression and letrozole. Conclusion: Here we show for the first time that two concurrent primary malignancies can be treated successfully during pregnancy with respect to maternal and fetal chances. Motivated modifications of breast cancer treatment (mastectomy instead of lumpectomy, AVBD instead of epirubicin-cyclophosphamide chemotherapy), allowed treatment of both cancers during pregnancy. Final treatment was administered after delivery.
ABSTRACT
Copy number alterations (CNAs) have increasingly become part of the diagnostic algorithm of glial tumors. Alterations such as homozygous deletion of CDKN2A/B, 7 +/ 10 - chromosome copy number changes or EGFR amplification are predictive of a poor prognosis. The codeletion of chromosome arms 1p and 19q, typically associated with oligodendroglioma, implies a more favorable prognosis. Detection of this codeletion by the current diagnostic standard, being fluorescence in situ hybridization (FISH), is sometimes however subject to technical and interpretation problems. In this study, we evaluated CNA detection by shallow whole-genome sequencing (sWGS) as an inexpensive, complementary molecular technique. A cohort of 36 glioma tissue samples, enriched with "difficult" and "ambiguous" cases, was analyzed by sWGS. sWGS results were compared with FISH assays of chromosomes 1p and 19q. In addition, CNAs relevant to glioblastoma diagnosis were explored. In 4/36 samples, EGFR (7p11.2) amplifications and homozygous loss of CDKN2A/B were identified by sWGS. Six out of 8 IDH-wild-type glioblastomas demonstrated a prognostic chromosome 7/chromosome 10 signature. In 11/36 samples, local interstitial and terminal 1p/19q alterations were detected by sWGS, implying that FISH's targeted nature might promote false arm-level extrapolations. In this cohort, differences in overall survival between patients with and without codeletion were better pronounced by the sequencing-based distinction (likelihood ratio of 7.48) in comparison to FISH groupings (likelihood ratio of 0.97 at diagnosis and 1.79 ± 0.62 at reobservation), suggesting sWGS is more accurate than FISH. We recognized adverse effects of tissue block age on FISH signals. In addition, we show how sWGS reveals relevant aberrations beyond the 1p/19q state, such as EGFR amplification, combined gain of chromosome 7 and loss of chromosome 10, and homozygous loss of CDKN2A/B. The findings presented by this study might stimulate implementation of sWGS as a complementary, easy to apply technique for copy number detection.
Subject(s)
Brain Neoplasms , Glioma , Brain Neoplasms/diagnosis , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Chromosome Deletion , Chromosomes, Human, Pair 19 , ErbB Receptors/genetics , Glioma/diagnosis , Glioma/genetics , Glioma/pathology , Homozygote , Humans , In Situ Hybridization, Fluorescence/methods , Isocitrate Dehydrogenase/genetics , Sequence DeletionABSTRACT
PURPOSE: Providing additional insights on the efficacy of human nuclear transfer (NT). Here, and earlier, NT has been applied to minimize transmission risk of mitochondrial DNA (mtDNA) diseases. NT has also been proposed for treating infertility, but it is still unclear which infertility indications would benefit. In this work, we therefore additionally assess the applicability of NT to overcome failed fertilization. METHODS: Patient 1 carries a homoplasmic mtDNA mutation (m.11778G > A). Seventeen metaphase II (MII) oocytes underwent pre-implantation genetic testing (PGT), while five MII oocytes were used for spindle transfer (ST), and one in vitro matured (IVM) metaphase I oocyte underwent early pronuclear transfer (ePNT). Patients 2-3 experienced multiple failed intracytoplasmic sperm injection (ICSI) and ICSI-assisted oocyte activation (AOA) cycles. For these patients, the obtained MII oocytes underwent an additional ICSI-AOA cycle, while the IVM oocytes were subjected to ST. RESULTS: For patient 1, PGT-M confirmed mutation loads close to 100%. All ST-reconstructed oocytes fertilized and cleaved, of which one progressed to the blastocyst stage. The reconstructed ePNT-zygote reached the morula stage. These samples showed an average mtDNA carry-over rate of 2.9% ± 0.8%, confirming the feasibility of NT to reduce mtDNA transmission. For patient 2-3 displaying fertilization failure, ST resulted in, respectively, 4/5 and 6/6 fertilized oocytes, providing evidence, for the first time, that NT can enable successful fertilization in this patient population. CONCLUSION: Our study showcases the repertoire of disorders for which NT can be beneficial, to overcome either mitochondrial disease transmission or failed fertilization after ICSI-AOA.
Subject(s)
Infertility , Mitochondrial Diseases , DNA, Mitochondrial/genetics , Fertilization , Fertilization in Vitro/methods , Humans , Infertility/genetics , Infertility/therapy , Oocytes , Sperm Injections, IntracytoplasmicABSTRACT
BACKGROUND: Paediatric tumours are often characterised by the presence of recurrent DNA copy number alterations (CNAs). These DNA copy number profiles, obtained from a tissue biopsy, can aid in the correct prognostic classification and therapeutic stratification of several paediatric cancer entities (e.g. MYCN amplification in neuroblastoma) and are part of the routine diagnostic practice. Liquid biopsies (LQBs) offer a potentially safer alternative for such invasive tumour tissue biopsies and can provide deeper insight into tumour heterogeneity. PROCEDURE: The robustness and reliability of LQB CNA analyses was evaluated. We performed retrospective CNA profiling using shallow whole-genome sequencing (sWGS) on paired plasma circulating cell-free DNA (cfDNA) and tissue DNA samples from routinely collected samples from paediatric patients (n = 128) representing different tumour entities, including osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, Wilms tumour, brain tumours and neuroblastoma. RESULTS: Overall, we observed a good concordance between CNAs in tissue DNA and cfDNA. The main cause of CNA discordance was found to be low cfDNA sample quality (i.e. the ratio of cfDNA (<700 bp) and high molecular weight DNA (>700 bp)). Furthermore, CNAs were observed that were present in cfDNA and not in tissue DNA, or vice-versa. In neuroblastoma samples, no false-positives or false-negatives were identified for the detection of the prognostic marker MYCN amplification. CONCLUSION: In future prospective studies, CNA analysis on LQBs that are of sufficient quality can serve as a complementary assay for CNA analysis on tissue biopsies, as either cfDNA or tissue DNA can contain CNAs that cannot be identified in the other biomaterial.
Subject(s)
Biomarkers, Tumor/genetics , Cell-Free Nucleic Acids/genetics , DNA Copy Number Variations/genetics , Liquid Biopsy/methods , Adolescent , Child , Child, Preschool , Feasibility Studies , Female , Humans , Male , Prospective Studies , Retrospective StudiesABSTRACT
Pathogenic variants of the myelin transcription factor-1 like (MYT1L) gene include heterozygous missense, truncating variants and 2p25.3 microdeletions and cause a syndromic neurodevelopmental disorder (OMIM#616,521). Despite enrichment in de novo mutations in several developmental disorders and autism studies, the data on clinical characteristics and genotype-phenotype correlations are scarce, with only 22 patients with single nucleotide pathogenic variants reported. We aimed to further characterize this disorder at both the clinical and molecular levels by gathering a large series of patients with MYT1L-associated neurodevelopmental disorder. We collected genetic information on 40 unreported patients with likely pathogenic/pathogenic MYT1L variants and performed a comprehensive review of published data (total = 62 patients). We confirm that the main phenotypic features of the MYT1L-related disorder are developmental delay with language delay (95%), intellectual disability (ID, 70%), overweight or obesity (58%), behavioral disorders (98%) and epilepsy (23%). We highlight novel clinical characteristics, such as learning disabilities without ID (30%) and feeding difficulties during infancy (18%). We further describe the varied dysmorphic features (67%) and present the changes in weight over time of 27 patients. We show that patients harboring highly clustered missense variants in the 2-3-ZNF domains are not clinically distinguishable from patients with truncating variants. We provide an updated overview of clinical and genetic data of the MYT1L-associated neurodevelopmental disorder, hence improving diagnosis and clinical management of these patients.