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PurposeTo analyse the clinical spectrum, genetic features, specific D4Z4 hypomethylation status and genotype–phenotype correlations for somatic mosaicism in facioscapulohumeral dystrophy (FSHD).MethodsThis was a prospective, hospital-based, case–control, observational study of 35 participants with FSHD with somatic mosaicism recruited over 10 years, with 17 penetrant patients and 18 non-penetrant mutation carriers. This study also included a univariate comparison of 17 paired mosaic and non-mosaic patients with FSHD.ResultsMosaic participants with FSHD varied in age of diagnosis (median 45; range 15–65 years), muscle strength (FSHD clinical score median 0; range 0–10 points), clinical severity (age-corrected clinical severity score (ACSS) median 0; range 0–467 points), D4Z4 repeats (median 3; range 2–5 units), mosaic proportion (median 55%; range 27%–72%) and D4Z4 methylation extent (median 49.82%; range 27.17%–64.51%). The genotypic severity scale and D4Z4 methylation extent were significantly associated with ACSS (p1=0.003; p2=0.002). Among the matched pairs, the 17 mosaic patients had shorter D4Z4 repeats, lower FSHD clinical scores and lower ACSS than non-mosaic patients. Additionally, 34 of 35 (97%) participants carried two mosaic arrays, while a single patient had three mosaic arrays (3%). Two cases also carried four-type non-mosaic arrays on chromosome 10 (translocation configuration).ConclusionsBroadly, this large mosaic FSHD cohort exhibited significant clinical heterogeneity and relatively slight disease severity. Both genotypic severity scale and D4Z4 hypomethylation status served as modifiers of clinical phenotypes. Consistent with previous reports, mitotic interchromosomal/intrachromosomal gene conversion without crossover was here identified as a major genetic mechanism underlying mosaic FSHD.

Limb girdle muscular dystrophy LGMD R7 telethonin-related is a rare autosomal recessive muscle disorder characterized by proximal muscle weakness of pelvic and shoulder girdles. Mutation in TCAP is responsible for LGMD R7, and the disease has a wide geographic distribution in diverse populations, but genotype-phenotype relationships remain unclear. We collected 5 LGMD R7 patients from three unrelated Chinese families. The average onset age was 16 ± 1.41; the initial symptoms included progressive proximal muscle weakness in limbs, difficulty in fast running, and asymmetric muscle atrophy in calves. Muscle MR imaging showed varying severity of fatty infiltration in the pelvic girdle, thigh, and calf muscles, and the severity of muscle infiltration was related to the length of the disease course. Muscle histopathology revealed aberrantly sized muscle fibers, internal nuclei, split fibers, rimmed vacuoles, monocyte invasion, and necrotic fibers. Sequencing identified one novel and one previously reported TCAP mutation. Our study extends the known distribution of this rare muscular dystrophy and presents the first detailed clinical and genetic characterizations of LGMD R7 cases from the Chinese population. Our work expands the mutation spectrum known for LGMD R7 and emphasizes the need for clinicians to consider TCAP mutations when evaluating patients with symptoms of limb girdle muscular dystrophy.

We here report a genome-editing strategy to correct spinal muscular atrophy (SMA). Rather than directly targeting the pathogenic exonic mutations, our strategy employed Cas9 and guide-sgRNA for the targeted disruption of intronic splicing-regulatory elements. We disrupted intronic splicing silencers (ISSs, including ISS-N1 and ISS + 100) of survival motor neuron (SMN) 2, a key modifier gene of SMA, to enhance exon 7 inclusion and full-length SMN expression in SMA iPSCs. Survival of splicing-corrected iPSC-derived motor neurons was rescued with SMN restoration. Furthermore, co-injection of Cas9 mRNA from Streptococcus pyogenes (SpCas9) or Cas9 from Staphylococcus aureus (SaCas9) alongside their corresponding sgRNAs targeting ISS-N1 into zygotes rescued 56% and 100% of severe SMA transgenic mice (Smn−/−, SMN2tg/−). The median survival of the resulting mice was extended to >400 days. Collectively, our study provides proof-of-principle for a new strategy to therapeutically intervene in SMA and other RNA-splicing-related diseases.

Due to the rarity of angioimmunoblastic T-cell lymphoma (AITL), very limited data concerning its incidence patterns and prognostic factors are available. This study aimed to explore the incidence, characteristics, survival outcomes, and prognostic factors of AITL.Age-adjusted incidence and temporal trends were calculated based on 1247 AITL patients from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER)-13 database. A total of 1525 AITL patients from the SEER-18 database and 43 patients from our single center were included for survival analysis and nomogram construction.The age-adjusted incidence for overall cohort was 0.123 [95% confidence interval (CI), 0.117-0.131) per 100 000 during 1992-2017. The overall incidence increased steeply at the rate of 15.3% (95%CI 11.0%-19.8%, P0.001) per year during 1992-2004, but remained stable during 2004-2017 (P=0.200). Similar incidence trends were observed in age, sex, and stage subgroups. The final nomograms consisted of four variables: age at diagnosis, sex, Ann Arbor stage, and primary site. The concordance index (C-index) of the nomogram for 5-year overall survival prediction was 0.717, 0.690 and 0.820 in the training cohort, validation cohort-1 and cohort-2, respectively. Regarding the disease-specific survival (DSS), the nomogram also demonstrated a good discrimination level, with the C-index for predicting the probability of DSS at 5 years of 0.716, 0.682 and 0.813 for the three cohorts, respectively. The calibration displayed good concordance between the nomogram-predicted and actual observed outcomes.The age-adjusted incidence for AITL was low during 1992-2017. The incidence continuously increased during 1992-2004, but remained stable during 2004-2017. The nomograms as proposed may provide a favorable and accurate prognostic survival prediction in AITL.

Background Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is the most common form of lipid storage myopathy. The disease is mainly caused by mutations in electron-transfer flavoprotein dehydrogenase gene (ETFDH), which leads to decreased levels of ETF:QO in skeletal muscle. However, the specific underlying mechanisms triggering such degradation remain unknown. Methods We constructed expression plasmids containing wild type ETF:QO and mutants ETF:QO-A84T, R175H, A215T, Y333C, and cultured patient-derived fibroblasts containing the following mutations in ETFDH: c.250G>A (p.A84T), c.998A>G (p.Y333C), c.770A>G (p.Y257C), c.1254_1257delAACT (p. L418TfsX10), c.524G>A (p.R175H), c.380T>A (p.L127P) and c.892C>T (p.P298S). We used in vitro expression systems and patient-derived fibroblasts to detect stability of ETF:QO mutants then evaluated their interaction with Hsp70 interacting protein CHIP with active/inactive ubiquitin E3 ligase carboxyl terminus using western blot and immunofluorescence staining. This interaction was confirmed in vitro and in vivo by co-immunoprecipitation and immunofluorescence staining. We confirmed the existence two ubiquitination sites in mutant ETF:QO using mass spectrometry (MS) analysis. Results We found that mutant ETF:QO proteins were unstable and easily degraded in patient fibroblasts and in vitro expression systems by ubiquitin-proteasome pathway, and identified the specific ubiquitin E3 ligase as CHIP, which forms complex to control mutant ETF:QO degradation through poly-ubiquitination. CHIP-dependent degradation of mutant ETF:QO proteins was confirmed by MS and site-directed mutagenesis of ubiquitination sites. Hsp70 is directly involved in this process as molecular chaperone of CHIP. Conclusions CHIP plays an important role in ubiquitin-proteasome pathway dependent degradation of mutant ETF:QO by working as a chaperone-assisted E3 ligase, which reveals CHIP's potential role in pathological mechanisms of late-onset MADD. This article is protected by copyright. All rights reserved.

Loss of CD20 is a major obstacle for the retreatment of relapsed/refractory diffuse large B cell lymphoma (DLBCL) with Rituximab-associated regimens. Histone deacetylation causes gene silencing and inhibits CD20 expression. Chidamide is a novel inhibitor for histone deacetylases (HDACs). We hypothesize that Chidamide could overcome Rituximab-mediated down-regulation of CD20 and facilitate Rituximab-induced killing. In this study, we determine the mechanism of synergy of Chidamide with Rituximab in DLBCL using in vitro and in vivo models. We found that the levels of CD20 protein surface expression on five DLBCL cell lines were significantly and positively correlated with the sensitivities of cells to Rituximab. Treatment with Rituximab significantly reduced CD20 surface expression at the protein levels. RNA sequencing showed that Chidamide significantly increased expression of more than 2000 transcriptomes in DLBCL cells, around 1000 transcriptomes belong to the cell membrane and cell periphery pathways, including MS4A1. Chidamide significantly increased CD20 surface expression in DLBCL cell lines. Combination with Chidamide significantly synergized Rituximab-induced cell death in vitro and significantly inhibited tumour growth in DLBCL-bearing xenograft mice. A patient with relapsed/refractory DLBCL achieved a complete response after three cycles combined treatment with Chidamide and Rituximab. In conclusion, our data demonstrate for the first time that inhibition of HDACs by Chidamide significantly enhanced Rituximab-induced tumour growth inhibition in vitro and in vivo. We propose that CD20 surface expression should be used clinically to evaluate treatment response in patients with DLBCL. Chidamide is a promising sensitizer for the retreatment of DLBCL with Rituximab.

Background: Hereditary spastic paraplegia type 5 (SPG5) is an ultra-rare neurogenetic axon-degenerative disease. The absence of treatment to prevent disease progression represents a major unmet clinical need. With a greater understanding of the pathophysiological basis of SPG5, opportunities have emerged for providing a targeted mechanistic therapy. The aims of this preliminary study were to investigate the efficacy of a PCSK9 inhibitor, Evolocumab, as a cholesterol-lowering therapy for reducing the accumulation of neurotoxic oxysterols and to evaluate the effects on axonal degeneration. Methods: This was as an open-label, evaluator-blind, single-center pilot study in which 23 SPG5 patients each received a single subcutaneous injections of 420 mg Evolocumab. Clinical data, CSF and blood were collected for analysis at enrollment and subsequent day 30. Induced pluripotent stem cells (iPSCs) were generated from the fibroblasts of a SPG5 patient to assess the mechanism of PCSK9 inhibitor’s effect on treatment. Findings: This trial is the largest sample-size prospective study among any treatment trial for SPG5. In this relatively homogeneous group of SPG5 patients (96% carried the same known nonsense mutation c.334 C>T; the median age was 34 years; disease duration was 16 years), we found that PCSK9 inhibitor significantly lowered levels of the toxic metabolite 27-hydroxycholesterol (27-OHC) in plasma (median (IQR), 589(487-644) vs. 396(348-468) ng/ml , P < 0.001). CSF 27-OHC decreased in 12 (71%) patients with a median reduction by 11% from the median 10 ng/ml before treatment to 8.3 ng/ml after treatment (P = 0.012). Most importantly, axonal degeneration, assessed by using neurofilament light (NFL) as a quantitative biomarker, receded at 30 days after single-dose Evolocumab treatment. Additionally, using iPSC-derived motor neurons, this study also showed that PCSK9 inhibitor had anti-apoptosis activity in SPG5 patients. Interpretation: The potential biological activity of cholesterol modulation for SPG5 patients, that is, alleviation of damage to axons from the effects of neurotoxic oxysterol, as well as the absence of adverse effects associated with the use of PCSK9 inhibitor therapy documented here deserves, in fact urges, full evaluation by well-designed long-term clinical trials. Trial Registration: This study is registered with ClinicalTrials.gov, number: NCT01892345. Funding Statement: This work has been supported by grants U1905210 (W.-J.C.), 81771230(W.-J.C.) and 81801130 (X.L.) from the National Natural Science Foundation of China, Joint Funds for the Innovation of Science and Technology of Fujian Province (2017Y9094) (W.-J.C.) and (2018Y9082) (N.W.), the Natural Science Foundation of Fujian Province (2019J02010) (W.-J.C.) and (2019J05076) (X.L.), the Key Clinical Specialty Discipline Construction Program of Fujian (N.W.). Declaration of Interests: All authors report no conflict of interest. Fujian medical university school of public health have received consultant fees as statistician to perform the data analysis. Ethics Approval Statement: The study protocol and informed consent procedures were approved by the institutional review board. Written informed consent was provided by the patients and their health care proxies.

Background: Facioscapulohumeral muscular dystrophy (FSHD) is characterized by asymmetric muscular deficit of facial, shoulder-girdle muscles, and descending to lower limb muscles, but it exists in several extramuscular manifestations or overlapping syndromes. Herein, we report a "complex disease plus" patient with FSHD1, accompanied by peripheral neuropathy and myoclonic epilepsy. Methods: Standard clinical assessments, particular auxiliary examination, histological analysis, and molecular analysis were performed through the new Comprehensive Clinical Evaluation Form, pulsed-field gel electrophoresis-based Southern blot, Multiplex Ligation-dependent Probe Amplification (MLPA), whole exome sequencing (WES), and targeted methylation sequencing. Results: The patient presented with mild facial weakness, humeral poly-hill sign, scapular winging, peroneal weakness, drop foot, pes cavus, and myoclonic epilepsy. Furthermore, electrophysiology revealed severely demyelinated and axonal injury. The muscle and nerve biopsy revealed broadly fiber Type II grouping atrophy and myelinated nerve fibers that significantly decreased with thin myelinated fibers and onion bulbs changes. Generalized sharp and sharp-slow wave complexes on electroencephalography support the diagnosis toward myoclonic epilepsy. In addition, molecular testing demonstrated a co-segregated 20-kb 4q35-EcoRI fragment and permissive allele A, which corresponded with D4Z4 hypomethylation status in the family. Both the patient’s mother and brother only presented the typical FSHD but lacked overlapping syndromes. However, no mutations for hereditary peripheral neuropathy and myoclonic epilepsy were discovered by MLPA and WES. Conclusions: The present study described a "tripe trouble" with FSHD, peripheral neuropathy, and myoclonic epilepsy, adding the spectrum of overlapping syndromes and contributing to the credible diagnosis of atypical phenotype. It would provide a direct clue on medical care and genetic counseling. Key words: Facioscapulohumeral Muscular Dystrophy; Myoclonic Epilepsy; Overlapping Syndromes; Peripheral Neuropathy; Triple Trouble

Spiking neural P systems are a new computing model incorporating the ideas of spiking neurons into membrane computing. It has been shown that they have powerful computational capability and potential capability in solving computationally hard problems. The paper describes the implementation of signed integer arithmetic operations on spiking neural P system with the inputs and outputs encoded as appropriate sequences of spikes. The present work may be considered as the basis for more complex applications, maybe for constructing computer chips or for solving general mathematical problems.