Nonketotic hyperglycinemia (NKH) is a relatively well‐characterized inborn error of metabolism that results in a combination of lethargy, hypotonia, seizures, developmental arrest, and, in severe ...cases, death early in life. Three genes encoding components of the glycine cleavage enzyme system—GLDC, AMT, and GCSH—are independently associated with NKH. We report on a patient with severe NKH in whom the homozygous pathogenic variant in AMT (NM_000481.3):c.602_603del (p.Lys201Thrfs*75) and the homozygous likely pathogenic variant in GLDC(NM_000170.2):c.2852C>A (p.Ser951Tyr) were both identified. Our patient demonstrates a novel combination of two homozygous disease‐causing variants impacting the glycine cleavage pathway at two different components, and elicits management‐ and genetic counseling‐related challenges for the family.
MicroRNA‐10b (miR‐10b) is a unique oncogenic miRNA that is highly expressed in all GBM subtypes, while absent in normal neuroglial cells of the brain. miR‐10b inhibition strongly impairs ...proliferation and survival of cultured glioma cells, including glioma‐initiating stem‐like cells (GSC). Although several miR‐10b targets have been identified previously, the common mechanism conferring the miR‐10b‐sustained viability of GSC is unknown. Here, we demonstrate that in heterogeneous GSC, miR‐10b regulates cell cycle and alternative splicing, often through the non‐canonical targeting via 5′UTRs of its target genes, including MBNL1‐3, SART3, and RSRC1. We have further assessed the inhibition of miR‐10b in intracranial human GSC‐derived xenograft and murine GL261 allograft models in athymic and immunocompetent mice. Three delivery routes for the miR‐10b antisense oligonucleotide inhibitors (ASO), direct intratumoral injections, continuous osmotic delivery, and systemic intravenous injections, have been explored. In all cases, the treatment with miR‐10b ASO led to targets’ derepression, and attenuated growth and progression of established intracranial GBM. No significant systemic toxicity was observed upon ASO administration by local or systemic routes. Our results indicate that miR‐10b is a promising candidate for the development of targeted therapies against all GBM subtypes.
Synopsis
Oncogenic miR‐10b highly expressed in glioblastoma and absent in normal brain tissues promotes the growth of heterogeneous glioma cell types. Teplyuk et al. describe common genes regulated by miR‐10b in glioma stem cells and demonstrate the efficacy of miR‐10b inhibition in established GBM models.
mRNA splicing and processing factors are regulated by miR‐10b through the non‐canonical 5′UTR binding in glioma‐derived neurospheres.
Growth of orthotopic glioblastoma (GBM) xenografts and allografts in mouse models is attenuated by local and systemic delivery of miR+NA inhibitors.
No systemic toxicity of miR‐10b inhibitors’ administration by local or systemic routes was observed.
Oncogenic miR‐10b highly expressed in glioblastoma and absent in normal brain tissues promotes the growth of heterogeneous glioma cell types. Teplyuk et al. describe common genes regulated by miR‐10b in glioma stem cells and demonstrate the efficacy of miR‐10b inhibition in established GBM models.
Mucopolysaccharidosis (MPS) are a group of inherited lysosomal storage disorders which are caused due to deficiencies in enzymes leading to accumulation of glycosaminoglycans. There is extensive ...literature available on the systemic impact of MPS. However, there is a deficit in the number of publications about the prevalence of gynecological problems in women with MPS. In this study, we aim to identify if there is a difference in the menstrual patterns, gynecological problems, and pregnancy complications in women with MPS in comparison to the control population. The study is designed as a case control study in which the cases are women diagnosed with MPS over the age of 12 who have begun menstruating, and the controls are women over the age of 12 without a diagnosis of MPS. Women who underwent a hematopoietic stem cell transplant were excluded from the study as the drugs used for this procedure could influence menstruation and fertility. The study was conducted in the form of a 34-question survey. The survey is divided into questions regarding demographics, menstruation and pregnancy outcomes. The menstrual questionnaire was scored, and chi square analysis was performed to analyze the differences between the case and control group. Data regarding pregnancy complications, age at menarche and use of enzyme replacement therapy were portrayed using descriptive statistics. The results of the study will be presented at the conference. Through this study we shed light on the menstrual and pregnancy complications found in women with MPS. We hope that this study will be the first step towards identifying any effect MPS disease may have on the reproductive system.
MicroRNA‐10b (miR‐10b) is a unique oncogenic miRNA that is highly expressed in all GBM subtypes, while absent in normal neuroglial cells of the brain. miR‐10b inhibition strongly impairs ...proliferation and survival of cultured glioma cells, including glioma‐initiating stem‐like cells (GSC). Although several miR‐10b targets have been identified previously, the common mechanism conferring the miR‐10b‐sustained viability of GSC is unknown. Here, we demonstrate that in heterogeneous GSC, miR‐10b regulates cell cycle and alternative splicing, often through the non‐canonical targeting via 5′UTRs of its target genes, including MBNL1‐3, SART3, and RSRC1. We have further assessed the inhibition of miR‐10b in intracranial human GSC‐derived xenograft and murine GL261 allograft models in athymic and immunocompetent mice. Three delivery routes for the miR‐10b antisense oligonucleotide inhibitors (ASO), direct intratumoral injections, continuous osmotic delivery, and systemic intravenous injections, have been explored. In all cases, the treatment with miR‐10b ASO led to targets’ derepression, and attenuated growth and progression of established intracranial GBM. No significant systemic toxicity was observed upon ASO administration by local or systemic routes. Our results indicate that miR‐10b is a promising candidate for the development of targeted therapies against all GBM subtypes.
Abstract
In the field of rare diseases, progress in molecular diagnostics led to the recognition that variants linked to autosomal-dominant neurodegenerative diseases of later onset can, in the ...context of biallelic inheritance, cause devastating neurodevelopmental disorders and infantile or childhood-onset neurodegeneration. TOR1A-associated arthrogryposis multiplex congenita 5 (AMC5) is a rare neurodevelopmental disorder arising from biallelic variants in TOR1A, a gene that in the heterozygous state is associated with torsion dystonia-1 (DYT1 or DYT-TOR1A), an early-onset dystonia with reduced penetrance. While 15 individuals with AMC5-TOR1A have been reported (less than 10 in detail), a systematic investigation of the full disease-associated spectrum has not been conducted.
Here, we assess the clinical, radiological and molecular characteristics of 57 individuals from 40 families with biallelic variants in TOR1A. Median age at last follow-up was 3 years (0–24 years). Most individuals presented with severe congenital flexion contractures (95%) and variable developmental delay (79%). Motor symptoms were reported in 79% and included lower limb spasticity and pyramidal signs, as well as gait disturbances. Facial dysmorphism was an integral part of the phenotype, with key features being a broad/full nasal tip, narrowing of the forehead and full cheeks. Analysis of disease-associated manifestations delineated a phenotypic spectrum ranging from normal cognition and mild gait disturbance to congenital arthrogryposis, global developmental delay, intellectual disability, absent speech and inability to walk. In a subset, the presentation was consistent with foetal akinesia deformation sequence with severe intrauterine abnormalities. Survival was 71%, with higher mortality in males. Death occurred at a median age of 1.2 months (1 week–9 years), due to respiratory failure, cardiac arrest or sepsis. Analysis of brain MRI studies identified non-specific neuroimaging features, including a hypoplastic corpus callosum (72%), foci of signal abnormality in the subcortical and periventricular white matter (55%), diffuse white matter volume loss (45%), mega cisterna magna (36%) and arachnoid cysts (27%). The molecular spectrum included 22 distinct variants, defining a mutational hotspot in the C-terminal domain of the Torsin-1A protein. Genotype-phenotype analysis revealed an association of missense variants in the 3-helix bundle domain to an attenuated phenotype, while missense variants near the Walker A/B motif as well as biallelic truncating variants were linked to early death.
In summary, this systematic cross-sectional analysis of a large cohort of individuals with biallelic TOR1A variants across a wide age-range delineates the clinical and genetic spectrum of TOR1A-related autosomal-recessive disease and highlights potential predictors for disease severity and survival.
In this cross-sectional analysis, Saffari et al. systematically assess the clinical, radiological, and molecular characteristics of 56 individuals with autosomal-recessive TOR1A-related disease. They delineate a broad and variable phenotypic spectrum, define core clinical symptoms, and highlight predictors for disease severity and survival.
Autosomal dominant variants in LDB3 (also known as ZASP), encoding the PDZ-LIM domain-binding factor, have been linked to a late onset phenotype of cardiomyopathy and myofibrillar myopathy in humans. ...However, despite knockout mice displaying a much more severe phenotype with premature death, bi-allelic variants in LDB3 have not yet been reported. Here we identify biallelic loss-of-function variants in five unrelated cardiomyopathy families by next-generation sequencing. In the first family, we identified compound heterozygous LOF variants in LDB3 in a fetus with bilateral talipes and mild left cardiac ventricular enlargement. Ultra-structural examination revealed highly irregular Z-disc formation, and RNA analysis demonstrated little/no expression of LDB3 protein with a functional C-terminal LIM domain in muscle tissue from the affected fetus. In a second family, a homozygous LDB3 nonsense variant was identified in a young girl with severe early-onset dilated cardiomyopathy with left ventricular non-compaction; the same homozygous nonsense variant was identified in a third unrelated female infant with dilated cardiomyopathy. We further identified homozygous LDB3 frameshift variants in two unrelated probands diagnosed with cardiomegaly and severely reduced left ventricular ejection fraction. Our findings demonstrate that recessive LDB3 variants can lead to an early-onset severe human phenotype of cardiomyopathy and myopathy, reminiscent of the knockout mouse phenotype, and supporting a loss of function mechanism.
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