OBJECTIVE: The clinicopathological risk factors in the prognosis of stage IV gastric cancer have been comprehensively studied. However, the influencing factors of stage IV gastric cancer prognosis at genomic and transcriptional levels have not been well defined.
METHODS: The mutational and transcriptional data, along with demographic, clinicopathological and prognostic information of 44 stage IV gastric cancer patients were downloaded from the TCGA database. Univariate and multivariate analyses were performed to identify the significant risk factors and a Nomogram model was established to predict the patient prognosis.
RESULTS: TTN, TP53, FLG, LRP1B, SYNE1 and ARID1A were among the top mutated genes without hot-spot mutations. The mutational status of AHNAK2, ASCC3, DNAH3, DOP1A, MYLK, SIPA1L1, SORBS2, SYNE1 and ANF462 significantly stratified the patient prognosis. The transcription of several genes, such as AQP10, HOXC8/9/10, COL10A1/COL11A1, WNT7B, KRT17 and KLK6 was significantly up-regulated or down-regulated. Enrichment analysis on mutations and transcription revealed cell skeleton and membrane function, extracellular matrix function, HPV infection, and several cancer-related pathways as the main aberrancies. Univariate analyses revealed a series of significant factors stratifying patient prognosis, mainly including cancer location, several mutated genes and many up- or down-regulated genes. However, subsequent multivariate analysis revealed SYNE1 mutation, DNAH3 mutation, COMMD3 transcription level, and cancer location as the independent risk factors. A Nomogram model has been established with these significant risk factors to predict the patient prognosis. Further validation is needed to ensure the effectiveness of the model in real clinical practice.
CONCLUSIONS: Cancer location, along with the mutational status of SYNE1 and DNAH3 and the transcriptional level of COMMD3 were independent risk factors of stage IV gastric cancer. A Nomogram model was established with these factors for prognosis prediction.

Mitochondrial disorders are characterized by a huge clinical, biochemical, and genetic heterogeneity, which poses significant diagnostic challenges. Several studies report that more than 50% of patients with suspected mitochondrial disease could have a non-mitochondrial disorder. Thus, only the identification of the causative pathogenic variant can confirm the diagnosis. Herein, we describe the diagnostic journey of a family suspected of having a mitochondrial disorder who were referred to our Genetics Department. The proband presented with the association of cerebellar ataxia, COX-negative fibers on muscle histology, and mtDNA deletions. Whole exome sequencing (WES), supplemented by a high-resolution array, comparative genomic hybridization (array-CGH), allowed us to identify two pathogenic variants in the non-mitochondrial SYNE1 gene. The proband and her affected sister were found to be compound heterozygous for a known nonsense variant (c.13258C>T, p.(Arg4420Ter)), and a large intragenic deletion that was predicted to result in a loss of function. To our knowledge, this is the first report of a large intragenic deletion of SYNE1 in patients with cerebellar ataxia (ARCA1). This report highlights the interest in a pangenomic approach to identify the genetic basis in heterogeneous neuromuscular patients with the possible cause of mitochondrial disease. Moreover, even rare copy number variations should be considered in patients with a phenotype suggestive of SYNE1 deficiency.

SYNE1, a nuclear envelope protein critical for cellular structure and signaling, is downregulated in numerous malignancies. SYNE1 alterations are found in 10% of gynecologic malignancies and 5% of epithelial ovarian cancers. Previous studies demonstrated an association between SYNE1 mutation, increased tumor mutation burden (TMB), and immunotherapy response. This study evaluates the SYNE1 mutation frequency, association with TMB, and downstream effects of SYNE1 mutation in ovarian cancer. Genetic information, including whole-exome sequencing, RNA analysis, and somatic tumor testing, was obtained for consenting ovarian cancer patients at an academic medical center. Mutation frequencies were compared between the institutional cohort and The Cancer Genome Atlas (TCGA). Bioinformatics analyses were performed. In our cohort of 50 patients, 16 had a SYNE1 mutation, and 15 had recurrent disease. Median TMB for SYNE1 mutated patients was 25 compared to 7 for SYNE1 wild-type patients (p < 0.0001). Compared to the TCGA cohort, our cohort had higher SYNE1 mutation rates (32% vs. 6%, p < 0.001). Gene expression related to immune cell trafficking, inflammatory response, and immune response (z > 2.0) was significantly increased in SYNE1 mutated patients. SYNE1 mutation is associated with increased TMB and immune cell infiltration in ovarian cancer and may serve as an additional biomarker for immunotherapy response.

We describe a case of severe adult-onset progressive tremulous cerebellar ataxia with pyramidal signs associated with a rare homozygous truncating pathogenic variant in the SYNE1 gene (p.Arg5371*). This contrasts the initial views on SYNE1-related ataxia as a relatively benign, slowly progressive condition, with important implications for clinic-genetic counselling.

BACKGROUND: Bladder cancer has a high rate of recurrence and high mortality rates in those who progress to muscle invasive disease. Biomarkers and molecular sub classification of tumours beyond standard histopathology has been proposed to address therapeutic dilemmas. The Cancer Genome Atlas project and other studies have contributed to the enhanced knowledge base of the mutational landscape of urothelial bladder cancer. Once again, these are mostly from Caucasian and Chinese patients, with data from the rest of Asia and Sri Lanka being sparse. The objective of this study was to assess the genomic variations of a cohort of urothelial bladder cancer patients in Sri Lanka.
METHODS: The molecular genetic study was conducted on formalin fixed paraffin embedded tumour samples of 24 patients, prospectively enrolled from 2013 to 2017. The samples were sequenced and variant distribution performed based on a 70-gene panel.
RESULTS: Total number of filtered mutations in the 24 patients was 10453. Median mutations per patient were 450 (range 22-987). The predominant mutational change was C>T and G>A. The top 5 mutated genes in our cohort were SYNE1, SYNE2, KMT2C, LRP2, and ANK2. The genes were clustered into 3 groups dependent on the number of mutations per patient per gene. The genes of cluster 1 and 2 mapped to Chromatin modifying enzymes and Generic Transcription Pathway. The chromatin remodelling pathway accounted for the largest proportion (22%) of mutations.
CONCLUSIONS: Clinical exome sequencing utilising a gene panel yielded a high mutation rate in our patients. The predominant mutational change was C>T and G>A. Three clusters of genes were identified. SYNE1 was the gene with the most mutations. The mutations comprised predominantly of genes of the chromatin remodelling pathway.

Mutations in the synaptic nuclear envelope protein 1 (SYNE1) gene are associated with substantial clinical heterogeneity. Here, we report the first case of SYNE1 ataxia in Taiwan due to two novel truncating mutations. Our patient, a 53-year-old female, exhibited pure cerebellar ataxia with c.1922del in exon 18 and c. C3883T mutations in exon 31. Previous studies have indicated that the prevalence of SYNE1 ataxia among East Asian populations is low. In this study, we identified 27 cases of SYNE1 ataxia from 22 families in East Asia. Of the 28 patients recruited in this study (including our patient), 10 exhibited pure cerebellar ataxia, and 18 exhibited ataxia plus syndromes. We could not find an exact correlation between genotypes and phenotypes. Additionally, we established a precise molecular diagnosis in our patient\'s family and extended the findings on the ethnic, phenotypic, and genotypic diversity of the SYNE1 mutational spectrum.

Mutations in genes encoding proteins associated with the linker of nucleoskeleton and cytoskeleton (LINC) complex within the nuclear envelope cause different diseases with varying phenotypes including skeletal muscle, cardiac, metabolic, or nervous system pathologies. There is some understanding of the structure of LINC complex-associated proteins and how they interact, but it is unclear how mutations in genes encoding them can cause the same disease, and different diseases with different phenotypes. Here, published mutations in LINC complex-associated proteins were systematically reviewed and analyzed to ascertain whether patterns exist between the genetic sequence variants and clinical phenotypes. This revealed LMNA is the only LINC complex-associated gene in which mutations commonly cause distinct conditions, and there are no clear genotype-phenotype correlations. Clusters of LMNA variants causing striated muscle disease are located in exons 1 and 6, and metabolic disease-associated LMNA variants are frequently found in the tail of lamin A/C. Additionally, exon 6 of the emerin gene, EMD, may be a mutation \"hot-spot\", and diseases related to SYNE1, encoding nesprin-1, are most often caused by nonsense type mutations. These results provide insight into the diverse roles of LINC-complex proteins in human disease and provide direction for future gene-targeted therapy development.

Identification of molecular regulators of hepatocellular carcinoma (HCC) initiation and progression is not well understood. We chemically induced HCC in male Wistar rats by administration of diethyl nitrosamine (DEN) and 2-acetylaminofluorene (2-AFF). Using 2D-electrophoresis and MALDI-TOF-MS/MS analyses, we characterized differentially expressed proteins in liver tissues at early stage of HCC progression. Using RT-PCR analysis, we quantified the mRNA expression of the characterized proteins and validated the transcript expression with tumor tissues of clinically confirmed HCC patients. Using bioinformatic tools, we analyzed a network among the introduced proteins that identified their interacting partners and analyzed the molecular mechanisms associated with signaling pathways during HCC progression. We characterized a protein, namely, pre-mRNA splicing factor 1 homolog (ISY1), which is upregulated at both transcriptome and proteome levels at HCC initiation, progression, and tumor stages. We analyzed the interacting partners of ISY1, namely, APOA-1, SYNE1, MMP10, and MTG1. Real-time PCR analysis confirmed elevated expression of APOA-1 mRNA at HCC initiation, progression, and tumor stages in animals undergoing tumorigenesis. The mRNA expression of the interacting partners was validated with tumor tissues of clinically confirmed liver cancer patients; the analysis revealed significant elevation in expression of transcripts. The transcriptome and proteome analyses complement each other and dysregulation in mRNA and protein expression of these regulators may play critical role in HCC initiation and progression.

BACKGROUND: Myogenic Arthrogryposis Multiplex Congenita type 3 (AMC-3), is a rare congenital condition characterized by severe hypotonia, club feet, and multiple joint contractures often affecting both arms and legs which start prior to birth.
METHODS: We report a full-term neonate born to first-degree cousins from fourth-generation consanguineous families, who had with antenatal history of reduced fetal movements. At birth, he was noticed to have bilateral club feet, arthrogryposis, severe hypotonia, and absent deep tendon reflexes. The patient developed difficulty in breathing probably attributed to his generalized severe hypotonia, necessitating mechanical ventilation. His creatinine-phospho-kinase, electromyogram, and brain magnetic resonance imaging were normal. Whole-exome sequencing (WES) was requested for the genetic diagnosis of the case. WES identified a novel homozygous variant c.23415-3799C > G p. in the synaptic nuclear envelope protein1 [SYNE1] gene. Seven out of 20 bioinformatic in silico programs predicted a pathogenic effect for this variant. Segregation analysis of the variant in the parents and siblings revealed that both parents and one sibling were heterozygous for the same mutation which proved the variant significance and its autosomal recessive pattern of inheritance.
CONCLUSIONS: AMC3 should be suspected in patients with decreased fetal movements, severe hypotonia, absent deep tendon reflexes, and arthrogryposis. SYNE1 gene mutations can be the underlying genetic defect and molecular genetic testing can prove the diagnosis.

BACKGROUND: Autosomal recessive spinocerebellar ataxia type 8 (ARCA1/SCAR8) is caused by mutations of the SYNE1 gene. The disease was initially described in families from Quebec (Canada) with a phenotype of pure cerebellar syndrome, but in recent years has been reported with a more variable clinical phenotype in other countries. Cases have recently been described of muscular dystrophy, arthrogryposis, and cardiomyopathy due to SYNE1 mutations.
OBJECTIVE: To describe clinical and molecular findings from 4 patients (3 men and one woman) diagnosed with ARCA1/SCAR8 from 3 Spanish families from different regions.
METHODS: We describe the clinical, paraclinical, and genetic results from 4 patients diagnosed with ARCA1/SCAR8 at different Spanish neurology departments.
RESULTS: Onset occurred in the third or fourth decade of life in all patients. After 15 years of progression, 3 patients presented pure cerebellar syndrome, similar to the Canadian patients; the fourth patient, with over 30 years\' progression, presented vertical gaze palsy, pyramidal signs, and moderate cognitive impairment. In all patients, MRI studies showed cerebellar atrophy. The genetic study revealed distinct pathogenic SYNE1 mutations in each family.
CONCLUSIONS: ARCA1/SCAR8 can be found worldwide and may be caused by many distinct mutations in the SYNE1 gene. The disease may manifest with a complex phenotype of varying severity.