AFF2 Is Associated With X-Linked Partial (Focal) Epilepsy With Antecedent Febrile Seizures

The differential expression of AFF3 in cervical cancer and its correlation with clinicopathological features and prognosis

BACKGROUND

Cervical cancer (CC) is the second most common malignancy in women, and identifying biomarkers of CC is crucial for prognosis prediction. Here, we investigated the expression of AF4/FMR2 Family Member 3 (AFF3) in CC and its association with clinicopathological features and prognosis.

METHODS

Tumour and adjacent tissues, along with clinicopathological features and follow-up information, were collected from 78 patients. AFF3 expression was assessed using quantitative real-time polymerase chain reaction and Western blotting. The correlation between AFF3 expression and CC symptoms was using chi-square test. The 5-year overall survival (OS) was analysed using the Kaplan-Meier method. The Univariate analysis of prognostic risk factors was conducted using the COX proportional hazards model, followed by multivariate COX regression analysis including variables with p < 0.01.

RESULTS

AFF3 expression was downregulated in CC, and its levels were correlated with lymph node metastasis (LNM) and International Federation of Gynaecology and Obstetrics (FIGO) stage. Patients with low AFF3 expression had a lower 5-year OS rate (52.78%, 19/36). Postoperative survival was reduced in patients with histological grade 3 (G3), myometrial invasion (depth ≥ 1/2), lymphovascular space invasion, LNM, and advanced FIGO stage. Low expression of AFF3 (HR: 2.848, 95% CI: 1.144-7.090) and histological grade G3 (HR: 4.393, 95% CI: 1.663-11.607) were identified as independent prognostic risk factors in CC patients.

CONCLUSION

Low expression of AFF3 and histological G3 are independent predictors of poor prognosis in CC patients, suggesting that AFF3 could serve as a potential biomarker for prognostic assessment in CC.

Investigation of FRMPD4 variants associated with X-linked epilepsy

BACKGROUND

The etiology of unexplained epilepsy in most patients remains unclear. Variants of FRMPD4 are suggested to be associated with neurodevelopmental disorders. Therefore, we screened for disease-causing FRMPD4 variants in patients with epilepsy.

METHODS

Trios-based whole-exome sequencing was conducted on a cohort of 85 patients with unexplained epilepsy, their parents, and extended family members. Additional cases with FRMPD4 variants were identified from the China Epilepsy Gene Matching Platform V.1.0. The frequency of variants was analyzed, and their subregional effects were predicted using in silico tools. The genotype-phenotype correlation of the newly defined causative genes and protein stability were analyzed using I-Mutant V.3.0 and Grantham scores.

RESULTS

Two novel missense variants of FRMPD4 were identified in two families. Using the gene matching platform, we identified three additional novel missense variants. These variants presented at low or no allele frequencies in the gnomAD database. All the variants were located outside the three FRMPD4 main domains (WW, PDZ, and FERM). In silico analyses revealed that the variants were damaging and were predicted to be the least stable. All patients eventually became seizure-free. Eight of the 21 patients with FRMPD4 variants had epilepsy, of which five (63%) had missense variants located outside the domains, two had deletions involving exon 2, and one had a frameshift variant located outside the domains. Patients with epilepsy caused by missense variants were often free of intellectual disabilities (4/5), whereas patients with epilepsy caused by truncated variants had intellectual disabilities and structural brain abnormalities (3/3).

CONCLUSIONS

The FRMPD4 gene is potentially associated with epilepsy. The genotype-phenotype correlation of FRMPD4 variants indicated that differences in variant types and locations of FRMPD4 may explain their phenotypic variation.

Association of FAT1 with focal epilepsy and correlation between seizure relapse and gene expression stage

PURPOSE

The FAT1 gene encodes FAT atypical cadherin 1, which is essential for foetal development, including brain development. This study aimed to investigate the relationship between FAT1 variants and epilepsy.

METHODS

Trio-based whole-exome sequencing was performed on a cohort of 313 patients with epilepsy. Additional cases with FAT1 variants were collected from the China Epilepsy Gene V.1.0 Matching Platform.

RESULTS

Four pairs of compound heterozygous missense FAT1 variants were identified in four unrelated patients with partial (focal) epilepsy and/or febrile seizures, but without intellectual disability/developmental abnormalities. These variants presented no/very low frequencies in the gnomAD database, and the aggregate frequencies in this cohort were significantly higher than those in controls. Two additional compound heterozygous missense variants were identified in two unrelated cases using the gene-matching platform. All patients experienced infrequent (yearly/monthly) complex partial seizures or secondary generalised tonic-clonic seizures. They responded well toantiseizure medication, but seizures relapsed in three cases when antiseizure medication were decreased or withdrawn after being seizure-free for three to six years, which correlated with the expression stage of FAT1. Genotype-phenotype analysis showed that epilepsy-associated FAT1 variants were missense, whereas non-epilepsy-associated variants were mainly truncated. The relationship between FAT1 and epilepsy was evaluated to be "Strong" by the Clinical Validity Framework of ClinGen.

CONCLUSIONS

FAT1 is a potential causative gene of partial epilepsy and febrile seizures. Gene expression stage was suggested to be one of the considerations in determining the duration ofantiseizure medication. Genotype-phenotype correlation helps to explain the mechanisms underlying phenotypic variation.

CD40LG-associated X-linked Hyper-IgM Syndrome (XHIGM) with pulmonary alveolar proteinosis: a case report

BACKGROUND

D40LG-associated X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis has rarely been reported, and its genotype-phenotypic correlation remains elusive.

CASE PRESENTATION

We describe a five-month-old boy with CD40LG mutation (c.516T > A, p.Tyr172Ter) X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis as the first manifestation. The patient completely recovered after immunotherapy and allogeneic hematopoietic stem cell transplantation. In addition, four previously reported patients with CD40LG mutation with pulmonary alveolar proteinosis were also analyzed. All of these patients presented with early onset of pulmonary infections and a good response to immunotherapy. The structural model of CD40LG indicated that all mutations caused the X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis to be located within the tumor necrosis factor homology domain.

CONCLUSIONS

A case was presented, and the characteristics of four cases of CD40LG-associated X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis were summarized. The variant locations may explain the phenotypic heterogeneity of patients with the CD40LG mutation.

Automatic Text-Mining Approach to Identify Molecular Target Candidates Associated with Metabolic Processes for Myotonic Dystrophy Type 1

Myotonic dystrophy type 1 (DM1) is an autosomal dominant hereditary disease caused by abnormal expansion of unstable CTG repeats in the 3' untranslated region of the myotonic dystrophy protein kinase (DMPK) gene. This disease mainly affects skeletal muscle, resulting in myotonia, progressive distal muscle weakness, and atrophy, but also affects other tissues and systems, such as the heart and central nervous system. Despite some studies reporting therapeutic strategies for DM1, many issues remain unsolved, such as the contribution of metabolic and mitochondrial dysfunctions to DM1 pathogenesis. Therefore, it is crucial to identify molecular target candidates associated with metabolic processes for DM1. In this study, resorting to a bibliometric analysis, articles combining DM1, and metabolic/metabolism terms were identified and further analyzed using an unbiased strategy of automatic text mining with VOSviewer software. A list of candidate molecular targets for DM1 associated with metabolic/metabolism was generated and compared with genes previously associated with DM1 in the DisGeNET database. Furthermore, g:Profiler was used to perform a functional enrichment analysis using the Gene Ontology (GO) and REAC databases. Enriched signaling pathways were identified using integrated bioinformatics enrichment analyses. The results revealed that only 15 of the genes identified in the bibliometric analysis were previously associated with DM1 in the DisGeNET database. Of note, we identified 71 genes not previously associated with DM1, which are of particular interest and should be further explored. The functional enrichment analysis of these genes revealed that regulation of cellular metabolic and metabolic processes were the most associated biological processes. Additionally, a number of signaling pathways were found to be enriched, e.g., signaling by receptor tyrosine kinases, signaling by NRTK1 (TRKA), TRKA activation by NGF, PI3K-AKT activation, prolonged ERK activation events, and axon guidance. Overall, several valuable target candidates related to metabolic processes for DM1 were identified, such as NGF, NTRK1, RhoA, ROCK1, ROCK2, DAG, ACTA, ID1, ID2 MYOD, and MYOG. Therefore, our study strengthens the hypothesis that metabolic dysfunctions contribute to DM1 pathogenesis, and the exploitation of metabolic dysfunction targets is crucial for the development of future therapeutic interventions for DM1.

Variants in BRWD3 associated with X-linked partial epilepsy without intellectual disability

AIMS

Etiology of the majority patients with idiopathic partial epilepsy (IPE) remains elusive. We thus screened the potential disease-associated variants in the patients with IPE.

METHODS

Trios-based whole exome sequencing was performed in a cohort of 320 patients with IPE. Frequency and molecular effects of variants were predicted.

RESULTS

Three novel BRWD3 variants were identified in five unrelated cases with IPE, which were four male cases and one female case. The variants included two recurrent missense variants (c.836C>T/p.Thr279Ile and c.4234A>C/p.Ile1412Leu) and one intronic variant close to splice site (c.2475 + 6A>G). The two missense variants were located in WD40 repeat domain and bromodomain, respectively. They were predicted to be damaging by silico tools and change hydrogen bonds with surrounding amino acids. The frequency of mutant alleles in this cohort was significantly higher than that in the controls of East Asian and all population of gnomAD. All these variants were inherited from the asymptomatic mothers. Four male cases presented frequent seizures at onset, while the female case only had two fever-triggered seizures. They showed good responses to valproate and lamotrigine, then finally became seizure free. All the cases had no intellectual disability. Further analysis demonstrated that all previously reported destructive variants of BRWD3 caused intellectual disability, while missense variants located in WD40 repeat domains and bromodomains of BRWD3 were associated with epilepsy.

CONCLUSION

BRWD3 gene is potentially associated with X-linked partial epilepsy without intellectual disability. The genotypes and locations of BRWD3 variants may explain for their phenotypic variation.

Phenotypic expansion of KCNH1-associated disorders to include isolated epilepsy and its associations with genotypes and molecular sub-regional locations

PURPOSE

Genotype-phenotypic correlation of KCNH1 variant remains elusive. This study aimed to expand the phenotypic spectrum of KCNH1 and explore the correlations between epilepsy and molecular sub-regional locations.

METHODS

We performed whole-exome sequencing in a cohort of 98 patients with familiar febrile seizure (FS) or epilepsy with unexplained etiologies. The damaging effects of variants were predicted by protein modeling and multiple in silico tools. All reported patients with KCNH1 pathogenic variants with detailed neurological phenotypes were analyzed to evaluate the genotype-phenotype correlation.

RESULTS

Two novel KCNH1 variants were identified in three cases, including two patients with FS with inherited variant (p.Ile113Thr) and one boy with epilepsy with de novo variant (p.Arg357Trp). Variant Ile113Thr was located within the eag domain, and variant p.Arg357Trp was located in transmembrane domain 4 of KCNH1, respectively. Two patients experienced refractory status epilepticus (SE), of which one patient died of acute encephalopathy induced by SE. Further analysis of 30 variants in 51 patients demonstrated that de novo variants were associated with epileptic encephalopathy, while mosaic/somatic or germline variants cause isolated epilepsy/FS. All hotspot variants associated with epileptic encephalopathy clustered in transmembrane domain (S4 and S6), while those with isolated epilepsy/seizures or TBS/ZLS without epilepsy were scattered in the KCNH1.

CONCLUSIONS

We found two novel missense variants of KCNH1 in three individuals with isolated FS/epilepsy. Variants in the KCNH1 cause a spectrum of epileptic disorders ranging from a benign form of genetic isolated epilepsy/FS to intractable form of epileptic encephalopathy. The genotypes and variant locations help explaining the phenotypic variation of patients with KCNH1 variant.