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Duchenne muscular dystrophy (DMD) is an X-linked syndrome that affects skeletal and cardiac muscle and is caused by mutation of the dystrophin gene. Induced pluripotent stem cells (iPSCs) were generated from dermal fibroblasts by electroporation with episomal vectors containing the reprogramming factors (OCT4, SOX2, LIN28, KLF4, and l-MYC). The donor carried an out-of-frame deletion of exons 45-50 of the dystrophin gene. The established iPSC line exhibited normal morphology, expressed pluripotency markers, had normal karyotype and possessed trilineage differentiation potential.

In the past, cannabis was commonly associated with mysticism and illegality. Fortunately, in recent years perspectives and discourses have changed. More prominence has been given to the rigorous scientific effort that led to the discovery of cannabis’ many physiological actions and endogenous signalling mechanisms. The endocannabinoid system is a complex and heterogeneous pro-homeostatic network comprising different receptors with several endogenous ligands, numerous metabolic enzymes and regulatory proteins. Therefore, it is not surprising that alterations and dysfunctions of the endocannabinoid system are observed in almost every category of disease. Such high degree of pathophysiological involvement suggests the endocannabinoid system is a promising therapeutic target and prompted the translation of resurgent scientific findings into clinical therapies. Shifting attitudes toward cannabis also raised other matters such as increased patient awareness, prescription requests, self-medication, recreational use, recognition of new knowledge gaps, renewed scientific activity, and seemingly exponential growth of the cannabis industry. This review, following a general overview of cannabis and the endocannabinoid system, assiduously describes its role within the context of cardiovascular diseases, paying particular attention to the Janus influence that endocannabinoid system modulators can have on the cardiovascular system.

Despite major progress in treating skeletal muscle disease associated with dystrophinopathies, cardiomyopathy is emerging as a major cause of death in people carrying dystrophin gene mutations that remain without a targeted cure even with new treatment directions and advances in modelling abilities. The reasons for the stunted progress in ameliorating dystrophin-associated cardiomyopathy (DAC) can be explained by the difficulties in detecting pathophysiological mechanisms which can also be efficiently targeted within the heart in the widest patient population. New perspectives are clearly required to effectively address the unanswered questions concerning the identification of authentic and effectual readouts of DAC occurrence and severity. A potential way forward to achieve further therapy breakthroughs lies in combining multiomic analysis with advanced preclinical precision models. This review presents the fundamental discoveries made using relevant models of DAC and how omics approaches have been incorporated to date.

X-linked intellectual disability (XLID) refers to a clinically and genetically heterogeneous neurodevelopmental disorder, in which males are more heavily affected than females. Among the syndromic forms of XLID, identified by additional clinical signs as part of the disease spectrum, the association between XLID and severe myopia has been poorly characterized. We used whole exome sequencing (WES) to study two Italian male twins presenting impaired intellectual function and adaptive behavior, in association with severe myopia and mild facial dysmorphisms. WES analysis detected the novel, maternally inherited, mutation c.916G > C (G306R) in the X-linked heparan sulfate 6-O-sulfotransferase 2 (HS6ST2) gene. HS6ST2 transfers sulfate from adenosine 3'-phosphate, 5'-phosphosulfate to the sixth position of the N-sulphoglucosamine residue in heparan sulfate (HS) proteoglycans. Low HS sulfation levels are associated with defective optic disc and stalk morphogenesis during mammalian visual system development. The c.916G>C variant affects the HS6ST2 substrate binding site, and its effect was considered "deleterious" by in-silico tools. An in-vitro enzymatic assay showed that the HS6ST2 mutant isoform had significantly reduced sulphotransferase activity. Taken together, the results suggest that mutant HS6ST2 is possibly involved in the development of myopia and cognitive impairment, characteristics of the probands reported here.

Beckwith-Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS) are imprinting-related disorders associated with genetic/epigenetic alterations of the 11p15.5 region, which harbours two clusters of imprinted genes (IGs). 11p15.5 IGs are regulated by the methylation status of imprinting control regions ICR1 and ICR2. 3D chromatin structure is thought to play a pivotal role in gene expression control; however, chromatin architecture models are still poorly defined in most cases, particularly for IGs. Our study aimed at elucidating 11p15.5 3D structure, via 3C and 3D FISH analyses of cell lines derived from healthy, BWS or SRS children. We found that, in healthy cells, IGF2/H19 and CDKN1C/KCNQ1OT1 domains fold in complex chromatin conformations, that facilitate the control of IGs mediated by distant enhancers. In patient-derived cell lines, we observed a profound impairment of such a chromatin architecture. Specifically, we identified a cross-talk between IGF2/H19 and CDKN1C/KCNQ1OT1 domains, consisting in in cis, monoallelic interactions, that are present in healthy cells but lost in patient cell lines: an inter-domain association that sees ICR2 move close to IGF2 on one allele, and to H19 on the other. Moreover, an intra-domain association within the CDKN1C/KCNQ1OT1 locus seems to be crucial for maintaining the 3D organization of the region.

Becker Muscular dystrophy (BMD) is an X-linked syndrome characterized by progressive muscle weakness. BMD is generally less severe than Duchenne Muscular Dystrophy. BMD is caused by mutations in the dystrophin gene that normally give rise to the production of a truncated but partially functional dystrophin protein. We generated an induced pluripotent cell line from dermal fibroblasts of a BMD patient carrying a splice mutation in the dystrophin gene (c.1705-8 T>C). The iPSC cell-line displayed the characteristic pluripotent-like morphology, expressed pluripotency markers, differentiated into cells of the three germ layers and had a normal karyotype.

Rubinstein-Taybi syndrome (RSTS) is a neurodevelopmental disorder characterized by growth retardation, skeletal anomalies and intellectual disability, caused by heterozygous mutation in either the CREBBP (RSTS1) or EP300 (RSTS2) genes. We generated an induced pluripotent stem cell line from an RSTS2 patient's blood mononuclear cells by Sendai virus non integrative reprogramming method. The iPSC line (IAIi001RSTS2-65-A) displayed iPSC morphology, expressed pluripotency markers, possessed trilineage differentiation potential and was stable by karyotyping. Mutation and western blot analyses demonstrated in IAIi001RSTS2-65-A the patient's specific non sense mutation in exon 23 c.3829A > T, p.(Lys 1277*) and showed reduced quantity of wild type p300 protein.

Duchenne muscular dystrophy (DMD) is caused by abnormalities in the dystrophin gene and is clinically characterised by childhood muscle degeneration and cardiomyopathy. We produced an induced pluripotent stem cell line from a DMD patient's dermal fibroblasts by electroporation with episomal vectors containing: hL-MYC, hLIN28, hSOX2, hKLF4, hOCT3/4. The resultant DMD iPSC line (CCMi001DMD-A-3) displayed iPSC morphology, expressed pluripotency markers, possessed trilineage differentiation potential and was karyotypically normal. MLPA analyses performed on DNA extracted from CCMi001DMD-A-3 showed a deletion of exons 49 and 50 (CCMi001DMD-A-3, ∆49, ∆50).

Duchenne's muscular dystrophy (DMD) is a neuromuscular disorder affecting skeletal and cardiac muscle function, caused by mutations in the dystrophin (DMD) gene. Dermal fibroblasts, isolated from a DMD patient with a reported deletion of exons 51 to 53 in the DMD gene, were reprogramed into induced pluripotent stem cells (iPSCs) by electroporation with episomal vectors containing the reprograming factors: OCT4, SOX2, LIN28, KLF4, and L-MYC. The obtained iPSC line showed iPSC morphology, expression of pluripotency markers, possessed trilineage differentiation potential and was karyotypically normal.

Background: Tumor epigenetic defects are of increasing relevance to clinical practice, because they are ‘druggable’ targets for cancer therapy using chromatin-remodeling agents (CRAs). New evidences highlight the importance of the microenvironment on the epigenome regulation and the need to use culture models able to preserve tissue morphology, to better understand the action of CRAs. Methods & methods: We studied the epigenetic response induced by culturing and CRAs in a preclinical model, preserving ex vivo the original tissue microenvironment and morphology, assessing different epigenetic signatures. Our overall findings suggest that culturing and CRAs cause heterogeneous effects on the genes methylation; CRAs affect the global DNA methylation and can trigger an active DNA demethylation; the culture induces alterations in the histone deacetylase expression. Conclusion: Despite the limited number of cases, these findings can be considered a proof of concept of the possibility to test CRAs epigenetic effects on ex vivo tissues maintained in their native tissue architecture.

The ultimate goal of precision disease modeling is to artificially recreate the disease of affected people in a highly controllable and adaptable external environment. This field has rapidly advanced which is evident from the application of patient-specific pluripotent stem-cell-derived precision therapies in numerous clinical trials aimed at a diverse set of diseases such as macular degeneration, heart disease, spinal cord injury, graft-versus-host disease, and muscular dystrophy. Despite the existence of semi-adequate treatments for tempering skeletal muscle degeneration in dystrophic patients, nonischemic cardiomyopathy remains one of the primary causes of death. Therefore, cardiovascular cells derived from muscular dystrophy patients’ induced pluripotent stem cells are well suited to mimic dystrophin-associated cardiomyopathy and hold great promise for the development of future fully effective therapies. The purpose of this article is to convey the realities of employing precision disease models of dystrophin-associated cardiomyopathy. This is achieved by discussing, as suggested in the title echoing William Shakespeare’s words, the settlements (or “leagues”) made by researchers to manage the constraints (“betwixt mine eye and heart”) distancing them from achieving a perfect precision disease model.

Patients affected by Duchenne muscular dystrophy (DMD) develop a progressive dilated cardiomyopathy characterized by inflammatory cell infiltration, necrosis, and cardiac fibrosis. Standard treatments consider the use of β-blockers and angiotensin-converting enzyme inhibitors that are symptomatic and unspecific toward DMD disease. Medications that target DMD cardiac fibrosis are in the early stages of development. We found immunoproteasome dysregulation in affected hearts of mdx mice (murine animal model of DMD) and cardiomyocytes derived from induced pluripotent stem cells of patients with DMD. Interestingly, immunoproteasome inhibition ameliorated cardiomyopathy in mdx mice and reduced the development of cardiac fibrosis. Establishing the immunoproteasome inhibition-dependent cardioprotective role suggests the possibility of modulating the immunoproteasome as new and clinically relevant treatment to rescue dilated cardiomyopathy in patients with DMD.

Duchenne’s muscular dystrophy is an X-linked neuromuscular disease that manifests as muscle atrophy and cardiomyopathy in young boys. However, a considerable percentage of carrier females are often diagnosed with cardiomyopathy at an advanced stage. Existing therapy is not disease-specific and has limited effect, thus many patients and symptomatic carrier females prematurely die due to heart failure. Early detection is one of the major challenges that muscular dystrophy patients, carrier females, family members and, research and medical teams face in the complex course of dystrophic cardiomyopathy management. Despite the widespread adoption of advanced imaging modalities such as cardiac magnetic resonance, there is much scope for refining the diagnosis and treatment of dystrophic cardiomyopathy. This comprehensive review will focus on the pertinent clinical aspects of cardiac disease in muscular dystrophy while also providing a detailed consideration of the known and developing concepts in the pathophysiology of muscular dystrophy and forthcoming therapeutic options.

MAP/microtubule affinity-regulating kinase 4 (MARK4) is a serine-threonine kinase that phosphorylates microtubule-associated proteins taking part in the regulation of microtubule dynamics. MARK4 is expressed in two spliced isoforms characterized by inclusion (MARK4S) or exclusion (MARK4L) of exon 16. The distinct expression profiles in the central nervous system and their imbalance in gliomas point to roles of MARK4L and MARK4S in cell proliferation and cell differentiation, respectively. Having ruled out mutations and transcription defects, we hypothesized that alterations in the expression of splicing factors may underlie deregulated MARK4 expression in gliomas. Bioinformatic analysis revealed four putative polypyrimidine-tract binding (PTB) protein binding sites in MARK4 introns 15 and 16. Glioma tissues and glioblastoma-derived cancer stem cells showed, compared with normal brain, significant overexpression of PTB, correlated with high MARK4L mRNA expression. Splicing minigene assays revealed a functional intronic splicing silencer in MARK4 intron 15, but mutagenesis of the PTB binding site in this region did not affect minigene splicing, suggesting that PTB may bind to a splicing silencer other than the predicted one and synergistically acting with the other predicted PTB sites. Electrophoretic mobility shift assays coupled with mass spectrometry confirmed binding of PTB to the polypyrimidine tract of intron 15, and thus its involvement in MARK4 alternative splicing. This finding, along with evidence of PTB overexpression in gliomas and glioblastoma-derived cancer stem cells and differentiated progeny, merged in pointing out the involvement of PTB in the switch to MARK4L, consistent with its established role in driving oncogenic splicing in brain tumors.

Becker muscular dystrophy (BMD) is a dystrophinopathy caused by mutations in the dystrophin gene on chromosome Xp21. BMD mutations result in truncated semi-functional dystrophin isoforms. Consequently, less severe clinical symptoms become apparent later in life compared to Duchenne muscular dystrophy. Dermal fibroblasts from a BMD patient were electroporated with episomal plasmids containing reprogramming factors to create the induced pluripotent stem cell line: CCMi002BMD-A-9 that showed pluripotent markers, were karyotypically normal and capable of trilineage differentiation. MLPA analyses performed on DNA extracted from CCMi002BMD-A-9 showed an in-frame deletion of exons 45 to 55 (CCMi002BMD-A-9 Δ45-55).

Rubinstein-Taybi syndrome (RSTS) is a neurodevelopmental disorder characterized by growth retardation, skeletal anomalies and intellectual disability, caused by heterozygous mutations in either CREBBP (RSTS1) or EP300 (RSTS2) genes. We characterized 3 iPSC lines generated by Sendai from blood of RSTS1 patients with unique non sense c.4435G > T, p.(Gly1479*), c.3474G > A, p.(Trp1158*) and missense c.4627G > T, p.(Asp1543Tyr) CREBBP mutations. All lines displayed iPSC morphology, pluripotency markers, trilineage differentiation potential, stable karyotype and specific mutations. Western-blot using a CREB-Binding Protein N-terminus antibody demonstrated the same amount of full length protein as control in the missense mutation line and reduced amount in lines with stop mutations.

Multicentric osteolysis, nodulosis and arthropathy (MONA) is a rare autosomal recessive disorder. To date, 13 mutations of the matrix metalloproteinase 2 (MMP2) gene have been detected in 26 patients with MONA and other osteolytic syndromes. Here, we describe the molecular and functional analysis of a novel MMP2 mutation in two adult Italian siblings with MONA. Both siblings displayed palmar-plantar subcutaneous nodules, tendon retractions, limb arthropathies, osteolysis in the toes and pigmented fibrous skin lesions. Molecular analysis identified a homozygous MMP2 missense mutation in exon 8 c.1228G>C (p.G410R), not detected in 260 controls and predicted by several bioinformatic tools to be pathogenic. By protein modelling, the mutant residue was predicted to affect the main chain conformation of the catalytic domain. Gelatin zymography, the gold standard test for MMP2 function, of serum-free conditioned medium from G410R-MMP2-expressing human embryonic kidney (HEK) cells, showed a complete loss of gelatinolytic activity. The novel mutation is located in the catalytic domain, as are 3 (p.E404K, p.V400del and p.G406D) of the other 13 MMP2 mutations described to date; however, p.G410R underlies a phenotype that is only partially overlapping that of other MMP2 exon 8 mutation carriers. Our results further delineate the complexity of genotype-phenotype correlations in MONA, broaden the repertoire of reported MMP2 mutation and enhance the comprehension of the protein motifs crucial for MMP2 catalytic activity.

MARK4 is a serine-threonine kinase that phosphorylates MAP proteins, increasing microtubule dynamics. MARK4 differs from the other members of the MARK family for encoding two isoforms (MARK4L and MARK4S), differentially expressed in the nervous system, and for the peculiar localisation at the centrosome and the midbody. By cytofluorimetric analysis we showed that MARK4 is expressed throughout the cell cycle and preferentially activated during mitosis. Depletion of MARK4S affected the morphology and proliferation of fibroblasts and glioma cells, as the percentages of cells in S and G2/M phases were reduced and the percentage of cells in G1 was increased. In MARK4S silenced cells, centrosomes were duplicated and positioned apically to the nucleus, indicating that the centrosome cycle was altered and the cells arrested in G1 phase. Overexpression of MARK4L or MARK4S reduced the density of the microtubule network, confirming microtubules as the main target of MARK4, and revealed a novel co-localisation of MARK4 and vimentin. Taken together, our data confirm that MARK4 is a key component in the regulation of microtubule dynamics and highlight its major role in cell cycle progression, particularly at the G1/S transition. The co-localisation of vimentin and MARK4L suggests that MARK4 has a wide-ranging influence on cytoskeleton.

Cornelia de Lange syndrome (CdLS) is a rare multisystem disorder characterized by facial dysmorphisms, limb anomalies, and growth and cognitive deficits. Mutations in genes encoding subunits (SMC1A, SMC3, RAD21) or regulators (NIPBL, HDAC8) of the cohesin complex account for approximately 65% of clinically diagnosed CdLS cases. The SMC1A gene (Xp11.22), responsible for 5% of CdLS cases, partially escapes X chromosome inactivation in humans and the allele on the inactive X chromosome is variably expressed. In this study, we evaluated overall and allele-specific SMC1A expression. Real-time PCR analysis conducted on 17 controls showed that SMC1A expression in females is 50% higher than in males. Immunoblotting experiments confirmed a 44% higher protein level in healthy females than in males, and showed no significant differences in SMC1A protein levels between controls and patients. Pyrosequencing was used to assess the reciprocal level of allelic expression in six female carriers of different SMC1A mutations and 15 controls who were heterozygous at a polymorphic transcribed SMC1A locus. The two alleles were expressed at a 1:1 ratio in the control group and at a 2:1 ratio in favor of the wild type allele in the test group. Since a dominant negative effect is considered the pathogenic mechanism in SMC1A-defective female patients, the level of allelic preferential expression might be one of the factors contributing to the wide phenotypic variability observed in these patients. An extension of this study to a larger cohort containing mild to borderline cases could enhance our understanding of the clinical spectrum of SMC1A-linked CdLS.