Genetic and molecular backgrounds of the development of glioblastoma / Genetyczne i molekularne podloza rozwoju glejaka.

Stage IV glioblastoma is the most frequently diagnosed and the worst prognosis tumor of the central nervous system (CNS). Patients suffering from this type of cancer usually survive several months with the use of surgical treatment, radiotherapy and chemotherapy. The development of glioblastoma is determined by a number of mutations, the most common of which are the p16, p19, p53, pRB, PTEN, PDGFR, CDK4 and EGFR protein genes as well as the loss of heterozygosity on chromosomes 10, 17 and 19. The occurrence of mutations within the IDH1 and IDH2 genes and increased methylation of MGMT promoter improves patient survival, but few patients live more than 3 years after diagnosis. The most important cell signaling pathways in glioblastoma are PI3K/Akt/mTOR and Wnt/ß-catenin, which play a key role in tumor cell function. However, these cells are highly resistant to anticancer drugs, including inhibitors of cell signaling pathways. Currently, the potential methods of effectively combating malignant gliomas are alternating electric field therapy and the implementation of new immunotherapeutic strategies.

IRAK1 Duplication in MECP2 Duplication Syndrome Does Not Increase Canonical NF-κB-Induced Inflammation.

PURPOSE: Besides their developmental and neurological phenotype, most patients with MECP2/IRAK1 duplication syndrome present with recurrent and severe infections, accompanied by strong inflammation. Respiratory infections are the most common cause of death. Standardized pneumological diagnostics, targeted anti-infectious treatment, and knowledge of the underlying pathomechanism that triggers strong inflammation are unmet clinical needs. We investigated the influence of IRAK1 overexpression on the canonical NF-κB signaling as a possible cause for excessive inflammation in these patients. METHODS: NF-κB signaling was examined by measuring the production of proinflammatory cytokines and evaluating the IRAK1 phosphorylation and degradation as well as the IκBα degradation upon stimulation with IL-1ß and TLR agonists in SV40-immortalized fibroblasts, PBMCs, and whole blood of 9 patients with MECP2/IRAK1 duplication syndrome, respectively. RESULTS: Both, MECP2/IRAK1-duplicated patients and healthy controls, showed similar production of IL-6 and IL-8 upon activation with IL-1ß and TLR2/6 agonists in immortalized fibroblasts. In PBMCs and whole blood, both patients and controls had a similar response of cytokine production after stimulation with IL-1ß and TLR4/2/6 agonists. Patients and controls had equivalent patterns of IRAK1 phosphorylation and degradation as well as IκBα degradation upon stimulation with IL-1ß. CONCLUSION: Patients with MECP2/IRAK1 duplication syndrome do not show increased canonical NF-κB signaling in immortalized fibroblasts, PBMCs, and whole blood. Therefore, we assume that these patients do not benefit from a therapeutic suppression of this pathway.

Biallelic variants in PIGN cause Fryns syndrome, multiple congenital anomalies-hypotonia-seizures syndrome, and neurologic phenotypes: A genotype-phenotype correlation study.

PURPOSE: Biallelic PIGN variants have been described in Fryns syndrome, multiple congenital anomalies-hypotonia-seizure syndrome (MCAHS), and neurologic phenotypes. The full spectrum of clinical manifestations in relation to the genotypes is yet to be reported. METHODS: Genotype and phenotype data were collated and analyzed for 61 biallelic PIGN cases: 21 new and 40 previously published cases. Functional analysis was performed for 2 recurrent variants (c.2679C>G p.Ser893Arg and c.932T>G p.Leu311Trp). RESULTS: Biallelic-truncating variants were detected in 16 patients-10 with Fryns syndrome, 1 with MCAHS1, 2 with Fryns syndrome/MCAHS1, and 3 with neurologic phenotype. There was an increased risk of prenatal or neonatal death within this group (6 deaths were in utero or within 2 months of life; 6 pregnancies were terminated). Incidence of polyhydramnios, congenital anomalies (eg, diaphragmatic hernia), and dysmorphism was significantly increased. Biallelic missense or mixed genotype were reported in the remaining 45 cases-32 showed a neurologic phenotype and 12 had MCAHS1. No cases of diaphragmatic hernia or abdominal wall defects were seen in this group except patient 1 in which we found the missense variant p.Ser893Arg to result in functionally null alleles, suggesting the possibility of an undescribed functionally important region in the final exon. For all genotypes, there was complete penetrance for developmental delay and near-complete penetrance for seizures and hypotonia in patients surviving the neonatal period. CONCLUSION: We have expanded the described spectrum of phenotypes and natural history associated with biallelic PIGN variants. Our study shows that biallelic-truncating variants usually result in the more severe Fryns syndrome phenotype, but neurologic problems, such as developmental delay, seizures, and hypotonia, present across all genotypes. Functional analysis should be considered when the genotypes do not correlate with the predicted phenotype because there may be other functionally important regions in PIGN that are yet to be discovered.

The Epidermal Transcriptome Analysis of a Novel c.639_642dup LORICRIN Variant-Delineation of the Loricrin Keratoderma Pathology.

Loricrin keratoderma (LK) is a rare autosomal dominant genodermatosis caused by LORICRIN gene mutations. The pathogenesis of the disease is not yet fully understood. So far, only 10 pathogenic variants in LORICRIN have been described, with all of them but one being deletions or insertions. The significance of rare nonsense variants remains unclear. Furthermore, no data regarding the RNA expression in affected patients are available. The aim of this study is to describe the two variants in the LORICRIN gene found in two distinct families: the novel pathogenic variant c.639_642dup and a rare c.10C > T (p.Gln4Ter) of unknown significance. We also present the results of the transcriptome analysis of the lesional loricrin keratoderma epidermis of a patient with c.639_642dup. We show that in the LK lesion, the genes associated with epidermis development and keratocyte differentiation are upregulated, while genes engaged in cell adhesion, differentiation developmental processes, ion homeostasis and transport, signaling and cell communication are downregulated. In the context of the p.Gln4Ter clinical significance evaluation, we provide data indicating that LORICRIN haploinsufficiency has no skin consequences. Our results give further insight into the pathogenesis of LK, which may have therapeutic implications in the future and important significance in the context of genetic counseling.

PIGN encephalopathy: Characterizing the epileptology.

OBJECTIVE: Epilepsy is common in patients with PIGN diseases due to biallelic variants; however, limited epilepsy phenotyping data have been reported. We describe the epileptology of PIGN encephalopathy. METHODS: We recruited patients with epilepsy due to biallelic PIGN variants and obtained clinical data regarding age at seizure onset/offset and semiology, development, medical history, examination, electroencephalogram, neuroimaging, and treatment. Seizure and epilepsy types were classified. RESULTS: Twenty six patients (13 female) from 26 families were identified, with mean age 7 years (range = 1 month to 21 years; three deceased). Abnormal development at seizure onset was present in 25 of 26. Developmental outcome was most frequently profound (14/26) or severe (11/26). Patients presented with focal motor (12/26), unknown onset motor (5/26), focal impaired awareness (1/26), absence (2/26), myoclonic (2/26), myoclonic-atonic (1/26), and generalized tonic-clonic (2/26) seizures. Twenty of 26 were classified as developmental and epileptic encephalopathy (DEE): 55% (11/20) focal DEE, 30% (6/20) generalized DEE, and 15% (3/20) combined DEE. Six had intellectual disability and epilepsy (ID+E): two generalized and four focal epilepsy. Mean age at seizure onset was 13 months (birth to 10 years), with a lower mean onset in DEE (7 months) compared with ID+E (33 months). Patients with DEE had drug-resistant epilepsy, compared to 4/6 ID+E patients, who were seizure-free. Hyperkinetic movement disorder occurred in 13 of 26 patients. Twenty-seven of 34 variants were novel. Variants were truncating (n = 7), intronic and predicted to affect splicing (n = 7), and missense or inframe indels (n = 20, of which 11 were predicted to affect splicing). Seven variants were recurrent, including p.Leu311Trp in 10 unrelated patients, nine with generalized seizures, accounting for nine of the 11 patients in this cohort with generalized seizures. SIGNIFICANCE: PIGN encephalopathy is a complex autosomal recessive disorder associated with a wide spectrum of epilepsy phenotypes, typically with substantial profound to severe developmental impairment.

Pharmacological chaperone therapy for the treatment of inborn errors of metabolism / Stosowanie farmakologicznych chaperonów w leczeniu wrodzonych chorób metabolicznych.

The article describes the mechanism of molecular and pharmacological chaperones in the treatment of inborn errors of metabolism. The literature review of the usage of ambroxol acting as a pharmacological chaperone for beta-glucocerebrosidase in Gaucher disease and Parkinson's disease associated with GBA variants has been reviewed.

Evidence of the milder phenotypic spectrum of c.1582G>A PIGT variant: Delineation based on seven novel Polish patients.

PIGT is one of over 29 glycosylphosphatidylinositol biosynthesis defect genes. Mutations cause genetically determined disorders characterized mainly by epilepsy with fever-sensitivity, central hypotonia, psychomotor delay and congenital malformations. The disease is known as multiple congenital anomalies-hypotonia-seizures syndrome 3 (MCAHS3) or glycosylphosphatidylinositol biosynthesis defect-7. Twenty-eight cases have been reported until today. We present seven novel Polish patients, all harboring 1582G>A variant in a homozygous or compound heterozygous state which seems to cause a milder phenotype of the disease.

Lessons learned from 40 novel PIGA patients and a review of the literature.

OBJECTIVE: To define the phenotypic spectrum of phosphatidylinositol glycan class A protein (PIGA)-related congenital disorder of glycosylation (PIGA-CDG) and evaluate genotype-phenotype correlations. METHODS: Our cohort encompasses 40 affected males with a pathogenic PIGA variant. We performed a detailed phenotypic assessment, and in addition, we reviewed the available clinical data of 36 previously published cases and assessed the variant pathogenicity using bioinformatical approaches. RESULTS: Most individuals had hypotonia, moderate to profound global developmental delay, and intractable seizures. We found that PIGA-CDG spans from a pure neurological phenotype at the mild end to a Fryns syndrome-like phenotype. We found a high frequency of cardiac anomalies including structural anomalies and cardiomyopathy, and a high frequency of spontaneous death, especially in childhood. Comparative bioinformatical analysis of common variants, found in the healthy population, and pathogenic variants, identified in affected individuals, revealed a profound physiochemical dissimilarity of the substituted amino acids in variant constrained regions of the protein. SIGNIFICANCE: Our comprehensive analysis of the largest cohort of published and novel PIGA patients broadens the spectrum of PIGA-CDG. Our genotype-phenotype correlation facilitates the estimation on pathogenicity of variants with unknown clinical significance and prognosis for individuals with pathogenic variants in PIGA.

Overlapping SETBP1 gain-of-function mutations in Schinzel-Giedion syndrome and hematologic malignancies.

Schinzel-Giedion syndrome (SGS) is a rare developmental disorder characterized by multiple malformations, severe neurological alterations and increased risk of malignancy. SGS is caused by de novo germline mutations clustering to a 12bp hotspot in exon 4 of SETBP1. Mutations in this hotspot disrupt a degron, a signal for the regulation of protein degradation, and lead to the accumulation of SETBP1 protein. Overlapping SETBP1 hotspot mutations have been observed recurrently as somatic events in leukemia. We collected clinical information of 47 SGS patients (including 26 novel cases) with germline SETBP1 mutations and of four individuals with a milder phenotype caused by de novo germline mutations adjacent to the SETBP1 hotspot. Different mutations within and around the SETBP1 hotspot have varying effects on SETBP1 stability and protein levels in vitro and in in silico modeling. Substitutions in SETBP1 residue I871 result in a weak increase in protein levels and mutations affecting this residue are significantly more frequent in SGS than in leukemia. On the other hand, substitutions in residue D868 lead to the largest increase in protein levels. Individuals with germline mutations affecting D868 have enhanced cell proliferation in vitro and higher incidence of cancer compared to patients with other germline SETBP1 mutations. Our findings substantiate that, despite their overlap, somatic SETBP1 mutations driving malignancy are more disruptive to the degron than germline SETBP1 mutations causing SGS. Additionally, this suggests that the functional threshold for the development of cancer driven by the disruption of the SETBP1 degron is higher than for the alteration in prenatal development in SGS. Drawing on previous studies of somatic SETBP1 mutations in leukemia, our results reveal a genotype-phenotype correlation in germline SETBP1 mutations spanning a molecular, cellular and clinical phenotype.

Neuropathophysiology, Genetic Profile, and Clinical Manifestation of Mucolipidosis IV-A Review and Case Series.

Mucolipidosis type IV (MLIV) is an ultra-rare lysosomal storage disorder caused by biallelic mutations in MCOLN1 gene encoding the transient receptor potential channel mucolipin-1. So far, 35 pathogenic or likely pathogenic MLIV-related variants have been described. Clinical manifestations include severe intellectual disability, speech deficit, progressive visual impairment leading to blindness, and myopathy. The severity of the condition may vary, including less severe psychomotor delay and/or ocular findings. As no striking recognizable facial dysmorphism, skeletal anomalies, organomegaly, or lysosomal enzyme abnormalities in serum are common features of MLIV, the clinical diagnosis may be significantly improved because of characteristic ophthalmological anomalies. This review aims to outline the pathophysiology and genetic defects of this condition with a focus on the genotype-phenotype correlation amongst cases published in the literature. The authors will present their own clinical observations and long-term outcomes in adult MLIV cases.

Post-Translational Modifications of Circulating Alpha-1-Antitrypsin Protein.

Alpha-1-antitrypsin (AAT), an acute-phase protein encoded by the SERPINA1 gene, is a member of the serine protease inhibitor (SERPIN) superfamily. Its primary function is to protect tissues from enzymes released during inflammation, such as neutrophil elastase and proteinase 3. In addition to its antiprotease activity, AAT interacts with numerous other substances and has various functions, mainly arising from the conformational flexibility of normal variants of AAT. Therefore, AAT has diverse biological functions and plays a role in various pathophysiological processes. This review discusses major molecular forms of AAT, including complex, cleaved, glycosylated, oxidized, and S-nitrosylated forms, in terms of their origin and function.

FGF12p.Gly112Ser variant as a cause of phenytoin/phenobarbital responsive epilepsy.

A patient harboring a novel p.Gly112Ser variant in FGF12 gene had a positive response to phenytoin/phenobarbital treatment. All the 11 previously reported FGF12-associated epilepsy cases had a single neighboring p.(Arg114His) variant and presented similar phenotype.

The remarkable phenotypic variability of the p.Arg269HiS variant in the TRPV4 gene.

INTRODUCTION: Mutations in the TRPV4 gene are associated with neuromuscular disorders and skeletal dysplasias, which present a phenotypic overlap. METHODS: Next-generation sequencing and Sanger sequencing were used to analyze the TRPV4 gene. RESULTS: We present 2 Polish families with TRPV4-related disorder harboring the same p.Arg269His mutation. The disease phenotypic expression was extremely variable (from mild scapular winging to severe hypotonia, global weakness, inability to walk unaided, congenital contractures, scoliosis, and respiratory insufficiency), but did not suggest anticipation. The 2 most severely affected patients showed congenital distal contractures of the upper limbs and involvement of cranial nerves (manifesting as facial asymmetry and strabismus). The disease course seemed to be stable, although in later stages it caused respiratory insufficiency and progression of physical disability. DISCUSSION: The phenotypic variability observed in p.Arg269His carriers suggests that an additional modifier or a more complex pathogenic mechanism exists. Muscle Nerve 59:129-133, 2019.

Mild phenotype of glutaric aciduria type 1 in polish patients - novel data from a group of 13 cases.

Glutaric aciduria type 1 is a neurometabolic disorder, caused by riboflavin-dependent glutaryl-CoA dehydrogenase deficiency. As its consequence, accumulation of the putatively neurotoxic metabolites (glutaric and 3-hydroxyglutaric acids) in body tissues, but especially within the brain, is observed. Estimated incidence of the disease is 1 in 110,000 newborns, The prevalence however may be higher, depending on a specific ethnic group, and result in phenotypic variation as well. In this paper we present clinical data of 13 patients of Polish nationality. They all present a mild phenotype and clinical course of glutaric aciduria type 1. Based on their clinical data, presented herein, we like to pay attention to the phenotypic and neuroimaging features important for the diagnosis of mild form of this disease. Moreover, we present novel molecular data, which may correlate with such a manifestation.

Clinical expression of Holt-Oram syndrome on the basis of own clinical experience considering prenatal diagnosis.

OBJECTIVES: Holt-Oram syndrome manifests with defects of upper limbs, pectoral girdle and cardiovascular system. The aim of this paper was to present complex clinical picture of the syndrome and its variable expression on the example of the family diagnosed genetically on the neonatal ward, after proband's prenatal examination. MARETIAL AND METHODS: Nine family members were tested for TBX5 gene mutation. RESULTS: Four of family members were diagnosed with Holt-Oram syndrome and five had correct genetic test results. The diagnosis allowed to identify a genetic risk family and enabled to provide them with genetic counselling. CONCLUSIONS: Diagnosis of Holt-Oram syndrome is possible as early as in prenatal period and it can be verified by genetic tests.

Infectious and immunologic phenotype of MECP2 duplication syndrome.

MECP2 (methyl CpG binding protein 2) duplication causes syndromic intellectual disability. Patients often suffer from life-threatening infections, suggesting an additional immunodeficiency. We describe for the first time the detailed infectious and immunological phenotype of MECP2 duplication syndrome. 17/27 analyzed patients suffered from pneumonia, 5/27 from at least one episode of sepsis. Encapsulated bacteria (S.pneumoniae, H.influenzae) were frequently isolated. T-cell immunity showed no gross abnormalities in 14/14 patients and IFNy-secretion upon ConA-stimulation was not decreased in 6/7 patients. In 6/21 patients IgG2-deficiency was detected - in 4/21 patients accompanied by IgA-deficiency, 10/21 patients showed low antibody titers against pneumococci. Supra-normal IgG1-levels were detected in 11/21 patients and supra-normal IgG3-levels were seen in 8/21 patients - in 6 of the patients as combined elevation of IgG1 and IgG3. Three of the four patients with IgA/IgG2-deficiency developed multiple severe infections. Upon infections pronounced acute-phase responses were common: 7/10 patients showed CRP values above 200 mg/l. Our data for the first time show systematically that increased susceptibility to infections in MECP2 duplication syndrome is associated with IgA/IgG2-deficiency, low antibody titers against pneumococci and elevated acute-phase responses. So patients with MECP2 duplication syndrome and low IgA/IgG2 may benefit from prophylactic substitution of sIgA and IgG.

Trends in prenatal diagnosis of non-specific multiple malformations disorders with reference to the own experience and research study on Smith-Lemli-Opitz syndrome.

AIM OF THE STUDY: Biochemical diagnosis of fetuses with multiple malformations--an attempt to determine the frequency of prenatal Smith-Lemli-Opitz syndrome. Discussion on trends in prenatal diagnosis of non-specific multiple malformations disorders. MATERIAL AND METHODS: A total of 117 fetal samples were obtained. They were analyzed with gas chromatography/mass spectrometry (GC/MS) method to assess the concentration of 7-dehydrocholesterol (7DHC) and 8-dehydrocholesterol (8DHC) in amniotic fluid samples and (or) to establish 7-dehydroestriol/estriol and 8-dehydropregnanetriol/pregnanetrio ratios in maternal urine. RESULTS: In 4 cases Smith-Lemll-Opitz syndrome was confirmed. CONCLUSIONS: Biochemical GC/MS sterol analyses of amniotic fluid or maternal urinary metabolites toward Smith- Lemli-Opitz syndrome, as cheap tests, should be performed in all pregnancies with suggestive ultrasound features (holoprosencephaly and(or) atrioventricular canal and(or) genital anomalies), especially when nuchal translucency is increased >3 mm, and after exclusion of chromosomal aberration in routine karyotyping or even arrayCGH.