Short Stature in Klinefelter Syndrome From Aggrecan Mutation.

Despite tall stature being a characteristic feature of Klinefelter syndrome, occasional cases of short stature have been reported. These cases are often attributed to GH deficiency. This case report details a unique case of a 16-year-old male with Klinefelter syndrome exhibiting proportionate short stature resulting from a heterozygous, likely pathogenic, variant in the ACAN gene c.7141G > A (p.Asp2381Asn). This specific variant, previously identified once in a family with a recessive inheritance pattern is reported here for the first time in an individual with Klinefelter syndrome. This report emphasizes the importance of a thorough evaluation and consideration of genetic testing for an underlying diagnosis in short-statured individuals with Klinefelter syndrome. Timely detection would enable appropriate therapeutic interventions.

The joint protective function of live- and dead-Lactobacillus plantarum GKD7 on anterior cruciate ligament transection induces osteoarthritis.

Osteoarthritis (OA) is a chronic inflammatory disease accompanied by joint pain, bone degradation, and synovial inflammation. Tumor necrosis factor (TNF)-α and interleukin (IL)-1ß play key roles in chronic inflammation, and matrix metalloproteinase (MMP)3 is the first enzyme released by chondrocytes and synovial cells that promotes MMPs' degrading cartilage matrix (including collage II and aggrecan) function. Using an anterior cruciate ligament transection (ACLT) rat model, Lactobacillus plantarum GKD7 has shown anti-inflammatory and analgesic properties. The present investigation examined the chondroprotective effects of several dosages and formulas of GKD7 on rats in an ACLT-induced OA model. The findings indicate that oral treatment with both live-GKD7 (GKD7-L) and dead-GKD7 (GKD7-D), along with celecoxib (positive control), all reduce post-ACLT pain and inflammation in OA joints. Subsequently, the immunohistochemical staining results demonstrate that following GKD7-L and GKD7-D treatment, there was a reversal of the degradation of collagen II and aggrecan, as well as a decrease in the expression of IL-1ß and TNF-α on the synovial tissue and MMP3 on the cartilage. Accordingly, our findings imply that the treatment of both GKD7-L and GKD7-D has chondroprotective and analgesic effects on the OA rat model, and that celecoxib and GKD7-L at dosages (100 mg/kg) have comparable therapeutic benefits. As a result, we propose that both GKD7-L and GKD7-D are helpful supplements for OA management.

Identification of extracellular matrix proteins in plasma as a potential biomarker for intervertebral disc degeneration.

PURPOSE: Recently, there has been significant focus on extracellular matrix proteolysis due to its importance in the pathological progression of intervertebral disc degeneration (IVDD). The present study investigates the circulating levels of extracellular matrix proteins in the plasma of IVDD and determines their potential relevance as biomarkers in disc degeneration. METHODS: Global proteomic analysis was performed in the plasma samples of 10 healthy volunteers (HV) and 10 diseased subjects (DS) after depletion of highly abundant proteins such as albumin and IgG. RESULTS: We identified 144 and 135 matrix-associated proteins in plasma samples from healthy volunteers (HV) and patients with disc degeneration (DS), respectively. Among these, 49 of the matrix-associated proteins were identical to the proteins found in intervertebral disc (IVD) tissues retrieved from the in-house library. Applying stringent parameters, we selected 28 proteins, with 26 present in DS and 21 in HV. 19 proteins were found common between the groups, two of which-aggrecan (ACAN) and fibulin 1 (FBLN1) - showed statistically significant differences. Specifically, ACAN was up-regulated and FBLN1 was down-regulated in the DS-plasma. In particular, DS-plasma exhibited specific expression of collagen type 2a1 (COL2A1), native to the nucleus pulposus. CONCLUSION: The distinct presence of collagen type 2a1 and the elevated expression of aggrecan in IVDD plasma may serve as the basis for the development of a potential biomarker for monitoring the progression of disc degeneration.

Cant1 Affects Cartilage Proteoglycan Properties: Aggrecan and Decorin Characterization in a Mouse Model of Desbuquois Dysplasia Type 1.

Desbuquois dysplasia type 1 (DBQD1) is a recessive chondrodysplasia caused by mutations in the CANT1 gene, encoding for the Golgi Calcium-Activated Nucleotidase 1 (CANT1). The enzyme hydrolyzes UDP, the by-product of glycosyltransferase reactions, but it might play other roles in different cell types. Using a Cant1 knock-out mouse, we demonstrated that CANT1 is crucial for glycosaminoglycan (GAG) synthesis; however, its impact on the biochemical properties of cartilage proteoglycans remains unknown. Thus, in this work, we characterized decorin and aggrecan from primary chondrocyte cultures and cartilage biopsies of mutant mice at post-natal day 4 by Western blots and further investigated their distribution in the cartilage extracellular matrix (ECM) by immunohistochemistry. We demonstrated that the GAG synthesis defect caused by CANT1 impairment led to the synthesis and secretion of proteoglycans with shorter GAG chains compared with wild-type animals. However, this alteration did not result in the synthesis and secretion of decorin and aggrecan in the unglycanated form. Interestingly, the defect was not cartilage-specific since also skin decorin showed a reduced hydrodynamic size. Finally, immunohistochemical studies in epiphyseal sections of mutant mice demonstrated that the proteoglycan structural defect moderately affected decorin distribution in the ECM.

Association of ADAMTS-5 gene polymorphisms with the susceptibility to knee osteoarthritis in a Chinese Han population.

BACKGROUND: Osteoarthritis (OA) is the most prevalent type of arthritis and the main reason for progressive disability in middle-aged and older people. Studies of candidate genes may provide a novel insight and treatment strategy for knee osteoarthritis (KOA). The aim of this study was to investigate the relationship between KOA susceptibility and single-nucleotide polymorphism (SNP) of the ADAMTS-5 gene. MATERIALS AND METHODS: The case group included 188 patients from Luoyang Orthopedic Hospital with clinically and radiographically diagnosed primary KOA, and the control group included 100 age-matched individuals without KOA. Fifteen ADAMTS-5 SNPs were assayed using MALDI-TOF MS. Allelic and haplotypic frequencies were compared between the groups. The relationship between genotype distribution and risk of KOA was analyzed by multivariate logistic regression. RESULTS: The frequency of A allele in rs2249350 site in the KOA group was significantly lower (odds ratio [OR]: 0.761; 95% confidence interval [95% CI]: 0.612-0.947; P = 0.016), while that of C allele was higher than that in the control group (OR: 1.176; 95% CI: 1.025-1.351; P = 0.016). AA genotype and gene model, especially recessive gene model at rs2249350 locus, negatively correlated with KOA risk after adjustment for sex, body mass index, age, and occupation (AA vs. CC: OR: 0.288; 95% CI: 0.124-0.669; P = 0.004; AA vs. CA + CC: OR: 0.348; 95% CI: 0.162-0.749; P = 0.007). Meanwhile, one protective haplotype, GA (rs229054, rs2249350) (OR: 0.763; 95% CI: 0.614-0.949; P = 0.017), and one high-risk haplotype, GC (rs229054, rs2249350) (OR: 1.259; 95% CI: 1.032-1.537; P = 0.019), were found in this study. CONCLUSION: Despite a limited sample size, our study suggests that the rs2249350 polymorphism in the ADAMTS-5 gene is one of the genetic factors influencing the risk of KOA. The A allele and AA genotype of rs2249350 may protect from KOA, whereas C allele and CC genotype increase the risk of KOA. In addition, the GA haplotype (rs229054, rs2249350) might be associated with a decreased risk of KOA, whereas the GC haplotype (rs229054, rs2249350) may be a risk factor for KOA. Additional larger-sized studies in more ethnically diverse populations are needed to confirm these findings.

A phase 2b double-blind placebo-controlled randomized clinical trial of SB-061, an aggrecan mimetic, in patients with symptomatic knee osteoarthritis.

OBJECTIVES: To evaluate the efficacy and safety of intra-articular injections of a novel aggrecan mimetic, SB-061, in subjects with knee osteoarthritis (OA). METHODS: This was a randomized, placebo-controlled, double-blind phase II study comparing intra-articular injections of SB-061 with placebo (isotonic saline) for 52 weeks, administered at baseline, Wk 16, and Wk 32. Eligible subjects had a KL grade of 2 or 3 on X-ray of the target knee and a Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) pain score ≥20 out of 50 at screening and baseline visits. Subjects having any other knee condition were excluded. Use of analgesics was prohibited, except for rescue medication. The primary endpoint was change from baseline (CFB) in WOMAC pain at Week 8. Secondary endpoints were CFB in WOMAC function and total, ICOAP, Patient Global Assessment, and 20-meter walk test. Exploratory endpoints included structural CFB in magnetic resonance imaging entities. RESULTS: A total of 288 subjects were randomized to SB-061 (n = 145) or placebo (n = 143), and 252 (87.5%) completed injections. The groups were comparable at baseline. The primary endpoint was not met, as no significant difference in the CFB of the WOMAC pain score at Week 8 between groups was observed, nor at any other time point during the study. Similarly, neither of the secondary or exploratory endpoints indicated any significant difference between groups. The frequency and type of adverse events were similar between groups. SB-061 was well-tolerated. CONCLUSION: Intra-articular injections of SB-061 administered at baseline, Week 16, and Week 32, over one year in subjects with knee OA, were safe but did not show any statistically significant effect on knee pain nor on other symptomatic or structural entities compared to placebo. TRIAL REGISTRATION NUMBER EUDRACT NO: 2019-004515-31.

Phagocytosis of aggrecan-positive perineuronal nets surrounding motor neurons by reactive microglia expressing MMP-9 in TDP-43Q331K ALS model mice.

Perineuronal nets (PNNs) are extracellular matrix structures that surround excitable neurons and their proximal dendrites. PNNs play an important role in neuroprotection against oxidative stress. Oxidative stress within motor neurons can act as a trigger for neuronal death, and this has been implicated in motor neuron degeneration in amyotrophic lateral sclerosis (ALS). We therefore characterised PNNs around alpha motor neurons and the possible contributing cellular factors in the mutant TDP-43Q331K transgenic mouse, a slow onset ALS mouse model. PNNs around alpha motor neurons showed significant loss at mid-stage disease in TDP-43Q331K mice compared to wild type strain control mice. PNN loss coincided with an increased expression of matrix metallopeptidase-9 (MMP-9), an endopeptidase known to cleave PNNs, within the ventral horn. During mid-stage disease, increased numbers of microglia and astrocytes expressing MMP-9 were present in the ventral horn of TDP-43Q331K mice. In addition, TDP-43Q331K mice showed increased levels of aggrecan, a PNN component, in the ventral horn by microglia and astrocytes during this period. Elevated aggrecan levels within glia were accompanied by an increase in fractalkine expression, a chemotaxic protein responsible for the recruitment of microglia, in alpha motor neurons of onset and mid-stage TDP-43Q331K mice. Following PNN loss, alpha motor neurons in mid-stage TDP-43Q331K mice showed increased 3-nitrotyrosine expression, an indicator of protein oxidation. Together, our observations along with previous PNN research provide suggests a possible model whereby microglia and astrocytes expressing MMP-9 degrade PNNs surrounding alpha motor neurons in the TDP-43Q331K mouse. This loss of nets may expose alpha-motor neurons to oxidative damage leading to degeneration of the alpha motor neurons in the TDP-43Q331K ALS mouse model.

Serum ARGS-aggrecan in a phase 2 clinical trial targeting osteoarthritis.

OBJECTIVE: To monitor serum concentrations of the aggrecan alanine-arginine-glycine-serine (ARGS) neoepitope in a clinical trial of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5 inhibition as disease-modifying therapy of knee osteoarthritis, and to investigate relationships between reduction in ARGS and change in cartilage thickness, knee-related pain and function. DESIGN: ROCCELLA trial participants received once-daily oral S201086 75, 150 or 300 mg, or placebo, for 52 weeks. Serum was collected at baseline, 4, 12, 28 and 52 weeks, and 2 weeks post-treatment with ARGS measured by an in-house immunoassay. Change from baseline to week 52 in central medial femorotibial compartment cartilage thickness was measured by magnetic resonance imaging, function and pain by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscores. Associations between cumulative change in ARGS and change in cartilage thickness or WOMAC subscores were evaluated by linear regression. RESULTS: S201086 reduced serum levels of ARGS in a dose-dependent manner throughout the treatment period. Maximal reduction was at 4 weeks with a 58.5% [95% CI 60.8%, 56.2%] reduction of ARGS compared to baseline for 300 mg S201086. Two weeks post-treatment, ARGS concentrations rebounded with a dose-dependent overshoot compared to baseline levels. Cumulative change of ARGS concentration from baseline to week 52 had no effect on change in cartilage thickness (slope -0.8×10-6 [-2.9×10-6, 1.3×10-6]) or change in WOMAC pain and function (slopes -30×10-6 [-64×10-6, 5.2×10-6] and -97×10-6 [-214×10-6, 20×10-6], respectively) at week 52. CONCLUSION: Systemic inhibition of ADAMTS-5 resulted in markedly reduced serum ARGS, but change in serum ARGS concentrations showed no association with the progression of cartilage thinning, or patient reported pain and function.

Evaluating anticancer activity of emodin by enhancing antioxidant activities and affecting PKC/ADAMTS4 pathway in thioacetamide-induced hepatocellular carcinoma in rats.

Emodin is a naturally occurring anthraquinone derivative with a wide range of pharmacological activities, including neuroprotective and anti-inflammatory activities. We aim to assess the anticancer activity of emodin against hepatocellular carcinoma (HCC) in rat models using the proliferation, invasion, and angiogenesis biomarkers. After induction of HCC, assessment of the liver impairment and the histopathology of liver sections were investigated. Hepatic expression of both mRNA and protein of the oxidative stress biomarkers, HO-1, Nrf2; the mitogenic activation biomarkers, ERK5, PKCδ; the tissue destruction biomarker, ADAMTS4; the tissue homeostasis biomarker, aggregan; the cellular fibrinolytic biomarker, MMP3; and of the cellular angiogenesis biomarker, VEGF were measured. Emodin increased the survival percentage and reduced the number of hepatic nodules compared to the HCC group. Besides, emodin reduced the elevated expression of both mRNA and proteins of all PKC, ERK5, ADAMTS4, MMP3, and VEGF compared with the HCC group. On the other hand, emodin increased the expression of mRNA and proteins of Nrf2, HO-1, and aggrecan compared with the HCC group. Therefore, emodin is a promising anticancer agent against HCC preventing the cancer prognosis and infiltration. It works through many mechanisms of action, such as blocking oxidative stress, proliferation, invasion, and angiogenesis.

Recombinant Human Proteoglycan Aggrecan-G1 Domain-induced Arthritis (GIA) Mouse Model.

The recombinant human proteoglycan aggrecan-G1 domain (rhG1)-induced arthritis (GIA) mouse model is a complex model of rheumatoid arthritis (RA). In GIA, autoimmune arthritis is induced by repeated intraperitoneal immunization of genetically susceptible BALB/c mice with the rhG1 antigen emulsified in the adjuvant dimethyldioctadecylammonium (DDA). This article describes the steps for producing and purifying the rhG1 antigen, the immunization protocol, methods for following the clinical picture of arthritis, and the evaluation of relevant laboratory parameters. In this model, the autoimmune arthritis develops stepwise, similar to RA: First is the preclinical stage (after the first immunization, days 0-20) with no sign of inflammation but detectable T and B cell activation; next, the stage of early arthritis (after the second immunization, days 21-41), where the first definitive signs of arthritis appear together with autoantibody production; and then the severe late-stage arthritis (after the third immunization, after day 42), which presents with massive inflammation of the limbs, leading to cartilage and bone destruction and finally ankylosis. The protocols described here provide sufficient information for investigators to use the GIA model to study different aspects of autoimmune arthritis. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Induction of recombinant human proteoglycan aggrecan-G1 domain (rhG1)-induced arthritis (GIA) Support Protocol 1: Production of rhG1-Xa-mFc2a fusion protein with CHOK1 mammalian expression system Support Protocol 2: Purification of the rhG1-Xa-mFc2a fusion protein by affinity chromatography Support Protocol 3: Preparation of DDA adjuvant Support Protocol 4: Clinical assessment of arthritis Support Protocol 5: Measurement of serum antibody levels and cytokines Support Protocol 6: Measurement of rhG1-induced proliferation and cytokine production in spleen cell culture Support Protocol 7: Histological assessment of arthritic limbs Support Protocol 8: Evaluation of arthritis with micro-computed tomography.

Genotype and phenotype in patients with ACAN gene variants: Three cases and literature review.

OBJECTIVE: To characterize the phenotype spectrum, diagnosis, and response to growth-promoting therapy in patients with ACAN variants causing familial short stature. METHODS: Three families with ACAN variants causing short stature were reported. Similar cases in the literature were summarized, and the genotype and phenotype were analyzed. RESULTS: Three novel heterozygous variants, c.757+1G>A, (splicing), c.6229delG, p.(Asp2078Tfs*1), and c.6679C>T, p.(Gln2227*) in the ACAN gene were identified. A total of 314 individuals with heterozygous variants from 105 families and 8 individuals with homozygous variants from 4 families were confirmed to have ACAN variants from literature and our 3 cases. Including our 3 cases, the variants reported comprised 33 frameshift, 39 missense, 23 nonsense, 5 splicing, 4 deletion, and 1 translocation variants. Variation points are scattered throughout the gene, while exons 12, 15, and 10 were most common (25/105, 11/105, and 10/105, respectively). Some identical variants existing in different families could be hot variants, c.532A>T, p.(Asn178Tyr), c.1411C>T, p.(Gln471*), c.1608C>A, p.(Tyr536*), c.2026+1G>A, (splicing), and c.7276G>T, p.(Glu2426*). Short stature, early-onset osteoarthritis, brachydactyly, midfacial hypoplasia, and early growth cessation were the common phenotypic features. The 48 children who received rhGH (and GnRHa) treatment had a significant height improvement compared with before (-2.18 ± 1.06 SD vs. -2.69 ± 0.95 SD, p < 0.001). The heights of children who received rhGH (and GnRHa) treatment were significantly improved compared with those of untreated adults (-2.20 ± 1.10 SD vs. -3.24 ± 1.14 SD, p < 0.001). CONCLUSION: Our study achieves a new understanding of the phenotypic spectrum, diagnosis, and management of individuals with ACAN variants. No clear genotype-phenotype relationship of patients with ACAN variants was found. Gene sequencing is necessary to diagnose ACAN variants that cause short stature. In general, appropriate rhGH and/or GnRHa therapy can improve the adult height of affected pediatric patients caused by ACAN variants.

Current status of immunological therapies for rheumatoid arthritis with a focus on antigen-specific therapeutic vaccines.

Rheumatoid arthritis (RA) is recognized as an autoimmune joint disease driven by T cell responses to self (or modified self or microbial mimic) antigens that trigger and aggravate the inflammatory condition. Newer treatments of RA employ monoclonal antibodies or recombinant receptors against cytokines or immune cell receptors as well as small-molecule Janus kinase (JAK) inhibitors to systemically ablate the cytokine or cellular responses that fuel inflammation. Unlike these treatments, a therapeutic vaccine, such as CEL-4000, helps balance adaptive immune homeostasis by promoting antigen-specific regulatory rather than inflammatory responses, and hence modulates the immunopathological course of RA. In this review, we discuss the current and proposed therapeutic products for RA, with an emphasis on antigen-specific therapeutic vaccine approaches to the treatment of the disease. As an example, we describe published results of the beneficial effects of CEL-4000 vaccine on animal models of RA. We also make a recommendation for the design of appropriate clinical studies for these newest therapeutic approaches, using the CEL-4000 vaccine as an example. Unlike vaccines that create or boost a new immune response, the clinical success of an immunomodulatory therapeutic vaccine for RA lies in its ability to redirect autoreactive pro-inflammatory memory T cells towards rebalancing the "runaway" immune/inflammatory responses that characterize the disease. Human trials of such a therapy will require alternative approaches in clinical trial design and implementation for determining safety, toxicity, and efficacy. These approaches include adaptive design (such as the Bayesian optimal design (BOIN), currently employed in oncological clinical studies), and the use of disease-related biomarkers as indicators of treatment success.

Evaluating the Anti-Osteoarthritis Potential of Standardized Boswellia serrata Gum Resin Extract in Alleviating Knee Joint Pathology and Inflammation in Osteoarthritis-Induced Models.

Osteoarthritis is a widespread chronic degenerative disease marked by the deterioration of articular cartilage, modifications in subchondral bone, and a spectrum of symptoms, including pain, stiffness, and disability. Ultimately, this condition impairs the patient's quality of life. This study aimed to evaluate the therapeutic efficacy of standardized Boswellia serrata gum resin extract (BSRE) in a rat model of monosodium iodoacetate (MIA)-induced osteoarthritis. A total of 60 rats were allocated into six groups: normal control group (NC), osteoarthritis control (injected with MIA, OC), O + B50 (injected with MIA and treated with 50 mg/kg body weight (BW) BSRE), O + B75 (injected with MIA and treated with 75 mg/kg BW BSRE), O + B100 (injected with MIA and treated with 100 mg/kg BW BSRE), and O + M (injected with MIA and treated with 150 mg/kg BW methyl sulfonyl methane). Several parameters, including knee joint swelling, histopathological changes, and the expression of collagen type II alpha 1 (COL2A1) and aggrecan, were comprehensively assessed. Concurrently, the serum levels and mRNA expression of inflammatory mediators, cytokines, and matrix metalloproteinases (MMPs) were analyzed in both the serum and knee joint synovium. The results demonstrated that BSRE significantly mitigated knee joint swelling, cartilage destruction, and tissue deformation. Notably, BSRE administration markedly upregulated the expression of COL2A1 and aggrecan while concurrently reducing levels of nitric oxide, prostaglandin E2, leukotriene B4, interleukin (IL)-6, and tumor necrosis factor (TNF)-α. Furthermore, a substantial decrease was observed in the mRNA expression of inducible nitric oxide synthase, cyclooxygenase-2, 5-lipoxygenase, IL-6, TNF-α and MMP-3 and -13, thereby indicating promising therapeutic implications for osteoarthritis. In conclusion, BSRE exhibited anti-inflammatory properties and inhibited cartilage matrix degradation in a rat model of MIA-induced osteoarthritis, with the O + B100 group showing significant reductions in swelling and notable improvements in joint cartilage damage. These findings illuminate the preventive and therapeutic potential of BSRE for osteoarthritis treatment, emphasizing the criticality of exhaustive evaluation of novel compounds.

Growth factors that drive aggrecan synthesis in healthy articular cartilage. Role for transforming growth factor-ß?

Introduction: Articular cartilage makes smooth movement possible and destruction of this tissue leads to loss of joint function. An important biomolecule that determines this function is the large aggregating proteoglycan of cartilage, aggrecan. Aggrecan has a relatively short half-life in cartilage and therefore continuous production of this molecule is essential. Methods: In this narrative review we discuss what is the role of growth factors in driving the synthesis of aggrecan in articular cartilage. A literature search has been done using the search items; cartilage, aggrecan, explant, Transforming Growth factor-ß (TGF-ß), Insulin-like Growth Factor (IGF), Bone Morphogenetic Protein (BMP) and the generic term "growth factors". Focus has been on studies using healthy cartilage and models of cartilage regeneration have been excluded. Results: In healthy adult articular cartilage IGF is the main factor that drives aggrecan synthesis and maintains adequate levels of production. BMP's and TGF-ß have a very limited role but appear to be more important during chondrogenesis and cartilage development. The major role of TGF-ß is not stimulation of aggrecan synthesis but maintenance of the differentiated articular cartilage chondrocyte phenotype. Conclusion: TGF-ß is a factor that is generally considered as an important factor in stimulating aggrecan synthesis in cartilage but its role in this might be very restrained in healthy, adult articular cartilage.

Clinicopathological Features of Three Rare EWSR1::NFATC2 Sarcomas of Bone and Soft Tissues.

Certain undifferentiated round cell sarcomas displaying EWSR1::NFATC2 fusion have recently been reported, mostly in the bones. This report presents clinicopathological features of 3 additional EWSR1::NFATC2 fusion sarcomas of bone and soft tissues. We present 2 soft tissue and 1 bone tumors: A 62-year-old man with pain and a slowly growing, 8-cm-sized soft tissue mass in the anterolateral compartment of his right calf, along with multiple pulmonary metastatic lesions; a 63-year-old man with a 5-cm sized axillary mass of 4 months duration and a cystic renal mass; and a 53-year-old man with a complaint of leg pain was found to have a 2-cm diameter, intramedullary, lytic mass in the diaphysis of his left femur. Microscopic examination of the tumors in all patients revealed round to epithelioid cells arranged in cords and trabeculae in a myxohyaline stroma. Immunohistochemically, the tumor cells were positive for MIC2/CD99 (3/3), EMA (3/3), NKX3.1 (3/3), NKX2.2 (2/2), CD10 (2/2), and aggrecan (1/1), while negative for S100P and GFAP. Various keratins were also negative except focal AE1/AE3 positivity in the third tumor. By fluorescence in-situ hybridization, 2 tumors (#1 and #3) revealed EWSR1 gene rearrangement and amplification. Furthermore, 2 tumors (#1 and #2) displayed EWSR1ex8::NFATC2ex3 fusion with next-generation sequencing (NGS). The first patient was offered chemotherapy. However, he died of pulmonary metastasis. This report highlights the value of combining histopathological features and immunostains such as NXK3.1, NKX2.2, CD10, and aggrecan, along with EWSR1 testing for triaging these tumors for rare gene fusions by NGS that has prognostic implications.

Investigation of the relationship between ACAN gene VNTR polymorphism and Alzheimer's disease in Turkish population.

Alzheimer's disease is one of the most common causes of dementia and is a neurodegenerative disease that occurs with memory loss, loss of language, thinking and problem-solving skills. In this study, it was aimed to reveal the relationship between Alzheimer's disease and the variable number tandem repeat (VNTR) polymorphism in the aggrecan (ACAN) gene. Thus, it is thought that it will contribute to enlightenment about disease by contributing to the pathophysiology of Alzheimer's disease. A total of 203 people, including 102 patients diagnosed with Alzheimer's and 101 healthy individuals, were included in the study. Deoxyribonucleic acid (DNA) extraction was performed from the blood samples taken. The variable number tandem repeat (VNTR) polymorphism of the ACAN gene was determined using the Polymerase Chain Reaction (PCR) method. In our study, the 30 R, 31 R and 33 R alleles were the most repetitive alleles in patients and controls. 30 R, 31 R and shorter alleles were more common in patients than in the control group and were found to be statistically significant (p = 0.042). According to our results, 30 R and 31 R alleles of the VNTR polymorphism in the ACAN gene may be associated with Alzheimer's disease. In addition, having less than 30 repeat alleles increases the risk of the disease by 2,202 times. Our study is the first to investigate the relationship between ACAN gene VNTR polymorphism and Alzheimer's disease. Further studies are needed to definitively relate it.

FMRP regulation of aggrecan mRNA translation controls perineuronal net development.

Perineuronal nets (PNNs) are mesh-like structures on the surfaces of parvalbumin-expressing inhibitory and other neurons, and consist of proteoglycans such as aggrecan, brevican, and neurocan. PNNs regulate the Excitatory/Inhibitory (E/I) balance in the brain and are formed at the closure of critical periods of plasticity during development. PNN formation is disrupted in Fragile X Syndrome, which is caused by silencing of the fragile X messenger ribonucleoprotein 1 (Fmr1) gene and loss of its protein product FMRP. FXS is characterized by impaired synaptic plasticity resulting in neuronal hyperexcitability and E/I imbalance. Here, we investigate how PNN formation is altered in FXS. PNNs are reduced in Fmr1 KO mouse brain when examined by staining for the lectin Wisteria floribunda agglutin (WFA) and aggrecan. Examination of PNNs by WFA staining at P14 and P42 in the hippocampus, somatosensory cortex, and retrosplenial cortex shows that they were reduced in these brain regions at P14 but mostly less so at P42 in Fmr1 KO mice. However, some differential FMRP regulation of PNN development in these brain regions persists, perhaps caused by asynchrony in PNN development between brain regions in wild-type animals. During development, aggrecan PNN levels in the brain were reduced in all brain regions in Fmr1 KO mice. Aggrecan mRNA levels were unchanged at these times, suggesting that FMRP is normally an activator of aggrecan mRNA translation. This hypothesis is buttressed by the observations that FMRP binds aggrecan mRNA and that ribosome profiling data show that aggrecan mRNA is associated with reduced numbers of ribosomes in Fmr1 KO mouse brain, indicating reduced translational efficiency. Moreover, aggrecan mRNA poly(A) tail length is also reduced in Fmr1 KO mouse brain, suggesting a relationship between polyadenylation and translational control. We propose a model where FMRP modulates PNN formation through translational up-regulation of aggrecan mRNA polyadenylation and translation.

Dose- and stage-dependent toxic effects of prenatal prednisone exposure on fetal articular cartilage development.

Prednisone is frequently used to treat rheumatoid diseases in pregnant women because of its high degree of safety. Whether prenatal prednisone exposure (PPE) negatively impacts fetal articular cartilage development is unclear. In this study, we simulated a clinical prednisone treatment regimen to examine the effects of different timings and doses of PPE on cartilage development in female and male fetal mice. Prednisone doses (0.25, 0.5, and 1 mg/kg/d) was administered to Kunming mice at different gestational stages (0-9 gestational days, GD0-9), mid-late gestation (GD10-18), or during the entire gestation (GD0-18) by oral gavage. The amount of matrix aggrecan (ACAN) and collagen type II a1(COL2a1), and expression of transforming growth factor ß1 (TGFß1) signaling pathway also demonstrated that the chondrocyte count and ACAN and COL2a1 expression reduced in fetal mice with early and mid-late PPE, with the reduction being more significant in the mice with early PPE than that in those with PPE at other stages. Prenatal exposure to different prednisone doses prevented the reduction of TGFß signaling pathway-related genes [TGFßR1, SMAD family member 3 (Smad3), SRY-box9 (SOX9)] as well as ACAN and COL2a1 mRNA expression levels in fetal mouse cartilage, with the most significant decrease after 1 mg/kg·d PPE. In conclusion, PPE can inhibit/restrain fetal cartilage development, with the greatest effect at higher clinical dose (1 mg/kg·d) and early stage of pregnancy (GD0-9), and the mechanism may be related to TGFß signaling pathway inhibition. The result of this study provide a theoretical and experimental foundation for the rational clinical use of prednisone.

Clinical Characteristics of Pathogenic ACAN Variants and 3-Year Response to Growth Hormone Treatment: Real-World Data.

INTRODUCTION: Heterozygous variants in the ACAN gene may underlie disproportionate short stature with characteristically accelerated bone age (BA) maturation and/or early-onset osteoarthritis (OA). METHODS: The objective of this study was to describe phenotype, analyze genotype-phenotype correlations, and assess the response of growth hormone (GH) treatment in children with a heterozygous ACAN variant. Thirty-six subjects (23 boys, 13 girls) with ACAN deficiency and treated for ≥1 year with GH were identified in the Dutch National Registry of GH treatment in children. RESULTS: We identified 25 different heterozygous ACAN variants in 36 subjects. Median (interquartile range) height SDS at start of GH was -2.6 SDS (-3.2 to -2.2). Characteristic features such as disproportion, advanced BA, early-onset OA, and dysmorphic features like midface hypoplasia and brachydactyly were present in the majority of children, but in ∼20%, no specific features were reported. Subjects with a truncating ACAN variant had a shorter height SDS compared to subjects with a non-truncating variant (-2.8 SDS and -2.1 SDS, respectively, p = 0.002). After 3 years of GH, height gain SDS in prepubertal children was 1.0 SDS (0.9-1.4). In pubertal children, height SDS remained relatively stable. CONCLUSION: The phenotype of subjects with pathogenic heterozygous ACAN variants is highly variable, and genetic testing for ACAN deficiency should be considered in any child with significant short stature, even in the absence of disproportion, specific dysmorphic features, or BA advancement. Furthermore, children with ACAN deficiency may benefit from GH with a modest but significant response, which is sustained during 3 years of treatment.

Prolonged use of temozolomide leads to increased anxiety and decreased content of aggrecan and chondroitin sulfate in brain tissues of aged rats.

Chemotherapy with temozolomide (TMZ) is an essential part of anticancer therapy used for malignant tumors (mainly melanoma and glioblastoma); however, the long-term effects on patient health and life quality are not fully investigated. Considering that tumors often occur in elderly patients, the present study was conducted on long-term (4 months) treatment of adult Wistar rats (9 months old, n=40) with TMZ and/or dexamethasone (DXM) to investigate potential behavioral impairments or morphological and molecular changes in their brain tissues. According to the elevated plus maze test, long-term use of TMZ affected the anxiety of the adult Wistar rats, although no significant deterioration of brain morphology or cellular composition of the brain tissue was revealed. The expression levels of all studied heparan sulfate (HS) proteoglycans (HSPGs) (syndecan-1, syndecan-3, glypican-1 and HSPG2) and the majority of the studied chondroitin sulfate (CS) proteoglycans (CSPGs) (decorin, biglycan, lumican, brevican, neurocan aggrecan, versican, Cspg4/Ng2, Cspg5 and phosphacan) were not affected by TMZ/DXM, except for neurocan and aggrecan. Aggrecan was the most sensitive proteoglycan to TMZ/DXM treatment demonstrating downregulation of its mRNA and protein levels following TMZ (-10-fold), DXM (-45-fold) and TMZ-DXM (-80-fold) treatment. HS content was not affected by TMZ/DXM treatment, whereas CS content was decreased 1.5-2.5-fold in the TMZ- and DXM-treated brain tissues. Taken together, the results demonstrated that treatment of adult Wistar rats with TMZ had long-term effects on the brain tissues, such as decreased aggrecan core protein levels and CS chain content and increased anxiety of the experimental animals.