Myotonic dystrophy type 1 (DM1) is a form of muscular dystrophy causing progressive muscle loss and weakness. Although clinical features can manifest at any age, it is the most common form of muscular dystrophy with onset in adulthood. DM1 is an autosomal dominant condition, resulting from an unstable CTG expansion in the 3\'-untranslated region of the myotonic dystrophy protein kinase (DMPK) gene. The age of onset and the severity of the phenotype are roughly correlated with the size of the CTG expansion. Multiple methodologies can be used to diagnose affected individuals with DM1, including polymerase chain reaction, Southern blot, and triplet repeat-primed polymerase chain reaction. Recently, triplet repeat interruptions have been described, which may affect clinical outcomes of a fully-variable allele in DMPK. This document supersedes the Technical Standards and Guidelines for Myotonic Dystrophy originally published in 2009 and reaffirmed in 2015. It is designed for genetic testing professionals who are already familiar with the disease and the methods of analysis.

Myotonic dystrophy type 1 is an autosomal dominant condition due to a CTG repeat expansion in the myotonic dystrophy protein kinase (DMPK) gene. This multisystem disorder affects multiple organ systems. Hypogonadism in males affected by myotonic dystrophy is commonly reported; however, the effect on female hypogonadism remains controversial. A 19-year-old female was referred to our genetics clinic due to primary amenorrhea without any family history of similar symptoms. Initial genetics evaluation identified a variant of uncertain significance in IGSF10, c.2210T>C (p.Phe737Ser). Follow-up genetic evaluation via whole genome sequencing identified at least 100 CTG repeats in the DMPK gene, thus resulting in the diagnosis of myotonic dystrophy type 1. The patient remains otherwise asymptomatic from myotonic dystrophy. This is the first report that demonstrates primary amenorrhea as a possible presenting feature of myotonic dystrophy type 1, thus providing evidence supporting female hypogonadism in myotonic dystrophy type 1.

Congenital myotonic dystrophy (CDM) is a genetic disease caused by an abnormally long CTG repeat expansion in the DMPK gene, which generally increases in size following intergenerational transmission. CDM is the rarest and most severe form of myotonic dystrophy type 1, yet an important number of patient-derived cells are needed to study this heterogeneous disease. Therefore, we have reprogrammed lymphoblastoid cells derived from a 3-year-old male with CDM into induced pluripotent stem cells (iPSCs; CBRCULi015-A) featuring 1800 CTG repeats and characterized their pluripotent state. This cell line constitutes an important resource to study CDM and potential treatments in vitro.

The tumor-associated macrophages (TAMs) play multifaceted roles in the progression of hepatocellular carcinoma (HCC). However, the involvement of circular RNAs in the interplay between TAMs and HCC remains unclear. Based on Transwell co-culturing and circular RNA sequencing, this study revealed that TAMs enhanced tumor glycolysis and progression by upregulating circMRCKα in HCC cells. Patients with HCC who exhibited elevated circMRCKα levels presented significantly reduced overall survival and greater cumulative recurrence. Notably, we identified a novel functional peptide of 227 amino acids named circMRCKα-227aa, encoded by circMRCKα. Mechanistically, circMRCKα-227aa bound to USP22 and enhanced its protein level to obstruct HIF-1α degradation via the ubiquitin-proteasome pathway, thereby augmenting HCC glycolysis and progression. In clinical HCC samples, a positive correlation was observed between the expression of circMRCKα and the number of infiltrating CD68+ TAMs and expression of USP22. Furthermore, circMRCKα emerged as an independent prognostic risk factor both individually and in conjunction with CD68+ TAMs and USP22. This study illustrated that circMRCKα-227aa, a novel TAM-induced peptide, promotes tumor glycolysis and progression via USP22 binding and HIF-1α upregulation, suggesting that circMRCKα and TAMs could be combined as therapeutic targets in HCC.

Myotonic dystrophy type 1 (DM1) is the most prevalent adult-onset muscular dystrophy affecting 1 in 8,000 individuals. It is characterized by multisystemic symptoms, primarily myopathy. The root cause of DM1 is a heterozygous CTG triplet expansion beyond the normal size threshold in the non-coding region of the DM1 protein kinase gene (DMPK). In our study, we generated and characterized three distinct DM1 induced pluripotent stem cell (iPSC) lines with CTG repeat expansions ranging from 900 to 2000 in the DMPK gene. These iPSC lines maintained normal karyotypes, exhibited distinctive colony morphology, robustly expressed pluripotency markers, differentiated into the three primary germ layers, and lacked residual viral vectors.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant disorder caused by an unstable expanded CTG repeat located in the 3\'-UTR of the DM1 protein kinase (DMPK) gene. The pathogenic mechanism results in misregulated alternative splicing of hundreds of genes, creating the dilemma of establishing which genes contribute to the mechanism of DM1 skeletal muscle pathology. In this issue of the JCI, Cisco and colleagues systematically tested the combinatorial effects of DM1-relevant mis-splicing patterns in vivo and identified the synergistic effects of mis-spliced calcium and chloride channels as a major contributor to DM1 skeletal muscle impairment. The authors further demonstrated the therapeutic potential for calcium channel modulation to block the synergistic effects and rescue myopathy.

Congenital myotonic dystrophy (CDM) is an autosomal dominant multisystemic disorder attributed to a large expansion of CTG trinucleotide repeats within the myotonic dystrophy protein kinase (DMPK) gene. In this study, we successfully reprogrammed dermal fibroblasts derived from two pediatric CDM patients and two age-matched individuals into induced pluripotent stem cells (iPSCs) using a non-integrating viral vector. The resulting CDM iPSC lines harbored approximately 2000 CTG repeats in the mutated DMPK allele. These iPSC lines expressed pluripotency markers and exhibited the capacity to differentiate into cells representing all three germinal layers, confirming their reliability as a research tool for investigating CDM and therapeutic strategies.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant multisystemic disease caused by a CTG repeat expansion in the 3\'-untranslated region (UTR) of DMPK gene. DM1 alleles containing non-CTG variant repeats (VRs) have been described, with uncertain molecular and clinical consequences. The expanded trinucleotide array is flanked by two CpG islands, and the presence of VRs could confer an additional level of epigenetic variability. This study aims to investigate the association between VR-containing DMPK alleles, parental inheritance and methylation pattern of the DM1 locus. The DM1 mutation has been characterized in 20 patients using a combination of SR-PCR, TP-PCR, modified TP-PCR and LR-PCR. Non-CTG motifs have been confirmed by Sanger sequencing. The methylation pattern of the DM1 locus was determined by bisulfite pyrosequencing. We characterized 7 patients with VRs within the CTG tract at 5\' end and 13 patients carrying non-CTG sequences at 3\' end of the DM1 expansion. DMPK alleles with VRs at 5\' end or 3\' end were invariably unmethylated upstream of the CTG expansion. Interestingly, DM1 patients with VRs at the 3\' end showed higher methylation levels in the downstream island of the CTG repeat tract, preferentially when the disease allele was maternally inherited. Our results suggest a potential correlation between VRs, parental origin of the mutation and methylation pattern of the DMPK expanded alleles. A differential CpG methylation status could play a role in the phenotypic variability of DM1 patients, representing a potentially useful diagnostic tool.

Myotonic dystrophy type 1 (DM1) is a genetic neuromuscular disorder that affects many organs, including the heart. DM1 is caused by a heterozygous CTG triplet expansion exceeding the normal size threshold in the non-coding region of the DM1 protein kinase gene (DMPK). We generated and characterized a DM1 iPSC line carrying a 700 CTG repeat expansion as well as a control iPSC line from a healthy individual. The two iPSC lines expressed several pluripotency markers, had the capacity to differentiate into the three primary germ layers, had no residual viral vectors, had normal karyotypes, and had a typical colony morphology.

BACKGROUND: Zhuidu Formula (ZDF) is composed of triptolide, cinobufagin and paclitaxel, which are the active ingredients of Tripterygium wilfordii Hook. F, dried toad skin and Taxus wallichiana var. chinensis (Pilg) Florin, respectively. Modern pharmacological studies show that triptolide, cinobufagin, and paclitaxel are well-known natural compounds that exert anti-tumor effects by interfering with DNA synthesis, inducing tumor cell apoptosis, and inhibiting the dynamic balance of the tubulin. However, the mechanism by which the three compounds inhibit triple-negative breast cancer (TNBC) metastasis is unknown.
OBJECTIVE: The objective of this investigation was to examine the inhibitory essences of ZDF on the metastasis of TNBC and elucidate its potential mechanism.
METHODS: Cell viability of triptolide (TPL), cinobufagin (CBF), and paclitaxel (PTX) on MDA-MB-231 cells was assessed employing a CCK-8 assay. The drug interactions of the three drugs on MDA-MB-231 cells were determined in vitro utilizing the Chou-Talalay method. MDA-MB-231 cells were identified for migration, invasion and adhesion in vitro through the implementation of the scratch assay, transwell assay and adhesion assay, respectively. The formation of cytoskeleton protein F-actin was detected by immunofluorescence assay. The expressions of MMP-2 and MMP-9 in the supernatant of the cells were determined by ELISA analysis. The Western blot and RT-qPCR were employed to explore the protein expressions associated with the dual signaling pathways of RhoA/ROCK and CDC42/MRCK. The anti-tumor efficacy of ZDF in vivo and its preliminary mechanism were investigated in the mouse 4T1 TNBC model.
RESULTS: The results demonstrated that ZDF could significantly reduce the viability of the MDA-MB-231 cell, and the combination index (CI) values of actual compatibility experimental points were all less than 1, demonstrating a favorable synergistic compatibility relationship. It was found that ZDF reduces RhoA/ROCK and CDC42/MRCK dual signaling pathways, which are responsible for MDA-MB-231cell migration, invasion, and adhesion. Additionally, there has been a significant reduction in the manifestation of cytoskeleton-related proteins. Furthermore, the expression levels of RhoA, CDC42, ROCK2, and MRCKβ mRNA and protein were down-regulated. ZDF significantly decreased the protein expressions of vimentin, cytokeratin-8, Arp2 and N-WASP, and inhibited actin polymerization and actomyosin contraction. Furthermore, MMP-2 and MMP-9 levels in the high-dose ZDF group were decreased by 30% and 26%, respectively. ZDF significantly reduced the tumor volume and protein expressions of ROCK2 and MRCKβ in tumor tissues without eliciting any perceptible alterations in the physical mass of the mice, and the reduction was more pronounced than that of the BDP5290 treated group.
CONCLUSIONS: The current investigation demonstrates that ZDF exhibits a proficient inhibitory impact on TNBC metastasis by regulating cytoskeletal proteins through the dual signaling pathways of RhoA/ROCK and CDC42/MRCK. Furthermore, the findings indicate that ZDF has significant anti-tumorigenic and anti-metastatic characteristics in breast cancer animal models.