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The intricate landscape of cellular processes governing gene transcription, chromatin organization, and genome stability is a fascinating field of study. A key player in maintaining this delicate equilibrium is the cohesin complex, a molecular machine with multifaceted roles. This review presents an in‐depth exploration of these intricate connections and their significant impact on various human diseases. [ABSTRACT FROM AUTHOR]

Cohesin is a highly conserved ring-shaped complex involved in topologically embracing chromatids, gene expression regulation, genome compartmentalization, and genome stability maintenance. Genomic analyses have detected mutations in the cohesin complex in a wide array of human tumors. These findings have led to increased interest in cohesin as a potential target in cancer therapy. Synthetic lethality has been suggested as an approach to exploit genetic differences in cancer cells to influence their selective killing. In this study, we show that mutations in ESCO1, NIPBL, PDS5B, RAD21, SMC1A, SMC3, STAG2, and WAPL genes are synthetically lethal with stimulation of WNT signaling obtained following LY2090314 treatment, a GSK3 inhibitor, in several cancer cell lines. Moreover, treatment led to the stabilization of β-catenin and affected the expression of c-MYC, probably due to the occupancy decrease in cohesin at the c-MYC promoter. Finally, LY2090314 caused gene expression dysregulation mainly involving pathways related to transcription regulation, cell proliferation, and chromatin remodeling. For the first time, our work provides the underlying molecular basis for synthetic lethality due to cohesin mutations and suggests that targeting the WNT may be a promising therapeutic approach for tumors carrying mutated cohesin. [ABSTRACT FROM AUTHOR]

The patient reported here underwent hematopoietic stem cell transplantation (HSCT) due to chronic granulomatous disease (CGD) caused by biallelic mutations of the NCF1 gene. Two years later, he developed AML, which was unexpected and was recognized via sex-mismatched chromosomes as deriving from the donor cells; the patient was male, and the donor was his sister. Donor cell leukemia (DCL) is very rare, and it had never been reported in patients with CGD after HSCT. In the subsequent ten years, the AML relapsed three times and the patient underwent chemotherapy and three further HSCTs; donors were the same sister from the first HSCT, an unrelated donor, and his mother. The patient died during the third relapse. The DCL was characterized since onset by an acquired translocation between chromosomes 9 and 11, with a molecular rearrangement between the MLL and MLLT3 genes—a quite frequent cause of AML. In all of the relapses, the malignant clone had XX sex chromosomes and this rearrangement, thus indicating that it was always the original clone derived from the transplanted sister's cells. It exhibited the ability to remain quiescent in the BM during repeated chemotherapy courses, remission periods and HSCT. The leukemic clone then acquired different additional anomalies during the ten years of follow-up, with cytogenetic results characterized both by anomalies frequent in AML and by different, non-recurrent changes. This type of cytogenetic course is uncommon in AML. [ABSTRACT FROM AUTHOR]

Background: Acute traumatic epidural hematoma (EDH) is a complication in 2–3% of pediatric head injuries. Surgery is mandatory in symptomatic cases; otherwise, conservative treatment is a valid approach, especially in the pediatric population. Ossified epidural hematomas (OEHs) have been reported in the pediatric population as a rare complication of conservative EDH management, although the exact incidence remains unknown. The progressive increase in conservative management may lead to increases in the OEH incidence over the next few years. Our study aimed to systematically review OEH incidence, management strategies, characteristics (thickness, inner/outer calcifications), complication rates, time to surgery after the EDH diagnosis, and clinical outcomes. Summary: A systematic review was conducted in accordance with the PRISMA guidelines. Studies reporting diagnoses and clear descriptions of OEH after EDH in pediatric patients were considered eligible. Sixteen studies, including 18 pediatric patients aged 0–18 years, were included. Head trauma was the most common cause of OEH. Seven (38.8%) OEHs were treated less than 1 month after EDH diagnosis. Surgery was performed in 17 cases (94.44%), while 1 asymptomatic case (5.56%) was managed conservatively. Key Messages: Surgery was the most commonly used treatment for OEH. Data for conservative treatment of OEH are limited. Magnetic resonance imaging or ultrasound within the first 2 months, to check for EDH resolution, may be crucial to rule out complications in pediatric patients. [ABSTRACT FROM AUTHOR]

Background Compression injuries of the thoracolumbar spine without neurological impairment are usually treated with minimally invasive procedures. Intravertebral expandable implants represent an alternative strategy in fractures with low fragments' displacement. Methods Patients with A2, A3 and A4 fractures of the T10--L2 spinal segment without neurological impairment, fracture gap >2 mm, vertebra plana, pedicle rupture, pedicle diameter <6 mm, spinal canal encroachment ≥50%, and vertebral body spread >30% were treated with the SpineJack device. Patients with pathological/ osteoporotic fractures were excluded. Demographic and fracture-related data were assessed together with vertebral kyphosis correction, vertebral height restoration/loss of correction and final kyphosis. The modified Rankin Scale (mRS), Oswestry Disability Index (ODI), Visual Analogue Scale (VAS), Smiley--Webster Pain Scale (SWPS) and EuroQol-5D (EQ-5D) were evaluated at 1 (-post), 6 and 12 months (-fup) after surgery. Statistical analysis was performed and p values ≤0.05 were considered significant. Results Fifty-seven patients were included in the study. Patients aged >60 years reported worse kyphosis correction (<4°) with more postoperative complications, while vertebral plasticity in younger patients, fragmentation-related greater remodeling in A3/ A4 fractures, and treatments within 7 days of trauma determined superior wedging corrections, with better EQ-5D-post and mRS-fup. Cement leakages did not affect functional outcome, while female gender and American Society of Anesthesiologists (ASA) score of 3-4 were associated with worse ODI-fup and VAS-fup. Although fracture characteristics and radiological outcome did not negatively influence the clinical outcome, A2 fracture was a risk factor for complications, thus indirectly compromising both the functional and radiological outcome. Conclusion With spread of <30%, the SpineJack is an alternative to minimally invasive fixations for treating A3/ A4 thoracolumbar fractures, being able to preserve healthy motion segments in younger patients and provide an ultraconservative procedure for elderly and fragile patients. [ABSTRACT FROM AUTHOR]

The screening of cohesin regulator NIPBL-mutation-negative individuals with sporadic and familial Cornelia de Lange syndrome (CdLS) and probands with CdLS-variant phenotypes for mutations in the cohesin complex components SMC3 and SMC1A (structural maintenance of chromosomes 1A) is reported. The analysis has shown that SMC3 and SMC1A mutations result in a consistently mild phenotype with absence of major structural anomalies associated with CdLS.

Autosomal recessive osteopetrosis (ARO) is a paradigm for genetic diseases that cause severe, often irreversible, defects before birth. In ARO, osteoclasts cannot remove mineralized cartilage, bone marrow is severely reduced, and bone cannot be remodeled for growth. More than 50% of the patients show defects in the osteoclastic vacuolar-proton-pump subunit, ATP6a3. We treated ATP6a3-deficient mice by in utero heterologous hematopoietic stem cell (HSC) transplant from outbred GFP transgenic mice. Dramatic phenotype rescue by GFP osteoclasts was obtained with engraftment, which was observed in most cases. Engraftment survived for variable periods. Recipients were not immunosuppressed, and graft-versus-host disease was not observed in all pups born after in utero treatment. Thus, differentiation of unmatched HSC transplanted in utero is sufficient to prevent fatal defects in ARO and may prevent complications of ARO unresponsive to conventional bone marrow transplantation. The presence of defective cells is not a barrier to the rescue of the phenotype by donor HSC. autosomal recessive osteopetrosis | bone marrow transplant | prenatal therapy

Abstract Background Claspin is a nuclear protein involved in DNA replication and damage response and is a key mediator for the S-phase checkpoint. Claspin expression is significantly high in several human solid tumors. Furthermore, high levels of claspin have been found in cervical cancer cell lines. Nevertheless, no data are available regarding claspin expression in cervical tissues. Methods In order to investigate whether claspin immunoreactivity is related to the lesion severity and High-Risk (HR) HPV infection, we analyzed claspin expression by immunohistochemistry in a series of cervical biopsies which represent the steps occurring during cervical carcinogenesis (normal tissues, Cervical Intraepithelial Neoplasias 1, 2 and 3, Squamous Cell Carcinomas). All patients also had a cervico-vaginal sample for HPV testing, collected immediately before the colposcopy-guided biopsy. The HR-HPV DNA detection was performed by the HR-HPV Hybrid Capture 2 test. HPV genotyping was performed using the Linear Array HPV Genotyping Test. Results Our results evidenced a constant and significant increase of the rate of claspin positivity from the normal tissues to carcinomas (pχ2trend 2 Conclusions Our findings indicate that in vivo claspin expression is significantly related to HR-HPV infection and lesion grade both in histological and cytological samples. Therefore, the analysis of claspin expression could be clinically relevant in the diagnosis of HPV-related cervical lesions, in particular when applied to cervico-vaginal cytology. Moreover, giving information on the proliferation rate of each lesion, claspin immunostaining may contribute to the evaluation of progression risk, thus being helpful in patient management. Nevertheless, only large prospective studies may clarify the true clinical usefulness of claspin expression in distinguishing lesions with different progression potential.

Cornelia de Lange syndrome (CdLS), Rubinstein–Taybi syndrome (RSTS), and KBG syndrome are three distinct developmental human disorders. Variants in seven genes belonging to the cohesin pathway, NIPBL, SMC1A, SMC3, HDAC8, RAD21, ANKRD11, and BRD4, were identified in about 80% of patients with CdLS, suggesting that additional causative genes remain to be discovered. Two genes, CREBBP and EP300, have been associated with RSTS, whereas KBG results from variants in ANKRD11. By exome sequencing, a genetic cause was elucidated in two patients with clinical diagnosis of CdLS but without variants in known CdLS genes. In particular, genetic variants in EP300 and ANKRD11 were identified in the two patients with CdLS. EP300 and ANKRD11 pathogenic variants caused the reduction of the respective proteins suggesting that their low levels contribute to CdLS‐like phenotype. These findings highlight the clinical overlap between CdLS, RSTS, and KBG and support the notion that these rare disorders are linked to abnormal chromatin remodeling, which in turn affects the transcriptional machinery. [ABSTRACT FROM AUTHOR]

Cornelia de Lange syndrome (CdLS) is a severe genetic disorder characterised by multisystemic malformations. CdLS is due to pathogenetic variants in NIPBL, SMC1A, SMC3, RAD21 and HDAC8 genes which belong to the cohesin pathway. Cohesin plays a pivotal role in chromatid cohesion, gene expression, and DNA repair. in this review, we will discuss how perturbations in those biological processes contribute to CdLS phenotype and will emphasise the state-of-art of CdLS therapeutic approaches. [ABSTRACT FROM AUTHOR]

Cornelia de Lange Syndrome (CdLS), due to mutations in genes of the cohesin protein complex, is described as a disorder of transcriptional regulation. Phenotypes in this expanding field include short stature, microcephaly, intellectual disability, variable facial features and organ involvement, resulting in overlapping presentations, including established syndromes and newly described conditions. Individuals with all forms of CdLS have multifaceted complications, including neurodevelopmental, feeding, craniofacial, and communication. Coping mechanisms and management of challenging behaviors in CdLS, disruption of normal behaviors, and how behavior molds the life of the individual within the family is now better understood. Some psychotropic medications are known to be effective for behavior. Other medications, for example, Indomethacin, are being investigated for effects on gene expression, fetal brain tissue, brain morphology and function in Drosophila, mice, and human fibroblasts containing CdLS‐related mutations. Developmental studies have clarified the origin of cardiac defects and role of placenta in CdLS. Chromosome architecture and cohesin complex structure are elucidated, leading to a better understanding of regulatory aspects and controls. As examples, when mutations are present, the formation of loop domains by cohesin, facilitating enhancer‐promotor interactions, can be eliminated, and embryologically, the nuclear structure of zygotes is disrupted. Several important genes are now known to interact with cohesin, including Brca2. The following abstracts are from the 8th Cornelia de Lange Syndrome Scientific and Educational Symposium, held in June 2018, Minneapolis, MN, before the CdLS Foundation National Meeting, AMA CME credits provided by GBMC, Baltimore, MD. All studies have been approved by an ethics committee. [ABSTRACT FROM AUTHOR]

Telomeres are nucleoprotein complexes that protect the ends of linear chromosomes from incomplete replication, degradation and detection as DNA breaks. Mammalian telomeres are protected by shelterin, a multiprotein complex that binds the TTAGGG telomeric repeats and recruits a series of additional factors that are essential for telomere function. Although many shelterin-associated proteins have been so far identified, the inventory of shelterin-interacting factors required for telomere maintenance is still largely incomplete. Here, we characterize AKTIP/Ft1 (human AKTIP and mouse Ft1 are orthologous), a novel mammalian shelterin-bound factor identified on the basis of its homology with the Drosophila telomere protein Pendolino. AKTIP/Ft1 shares homology with the E2 variant ubiquitin-conjugating (UEV) enzymes and has been previously implicated in the control of apoptosis and in vesicle trafficking. RNAi-mediated depletion of AKTIP results in formation of telomere dysfunction foci (TIFs). Consistent with these results, AKTIP interacts with telomeric DNA and binds the shelterin components TRF1 and TRF2 both in vivo and in vitro. Analysis of AKTIP- depleted human primary fibroblasts showed that they are defective in PCNA recruiting and arrest in the S phase due to the activation of the intra S checkpoint. Accordingly, AKTIP physically interacts with PCNA and the RPA70 DNA replication factor. Ft1-depleted p53-/- MEFs did not arrest in the S phase but displayed significant increases in multiple telomeric signals (MTS) and sister telomere associations (STAs), two hallmarks of defective telomere replication. In addition, we found an epistatic relation for MST formation between Ft1 and TRF1, which has been previously shown to be required for replication fork progression through telomeric DNA. Ch-IP experiments further suggested that in AKTIP-depleted cells undergoing the S phase, TRF1 is less tightly bound to telomeric DNA than in controls. Thus, our results collectively suggest that AKTIP/Ft1 works in concert with TRF1 to facilitate telomeric DNA replication. [ABSTRACT FROM AUTHOR]