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Background and Objectives: Endocrine complications have been described in patients affected by RASopathies but no systematic assessment has been reported. In this study, we investigate the prevalence of endocrine disorders in a consecutive unselected cohort of patients with RASopathies. Study Design: 72 patients with a genetically confirmed RASopathy (Noonan syndrome [NS], N=53; 29 LEOPARD syndrome [LS], N=2; cardiofaciocutaneous syndrome [CFCS], N=14; subjects showing co-occurring pathogenic variants in PTPN11 and NF1, N=3) and an age- and sex-matched healthy controls were included in the study. Endocrine system involvement was investigated by assessing the thyroid function, pubertal development, auxological parameters, adrenal function and bone metabolism. Results: Short stature was detected in 40% and 64% of the NS and CFCS subcohorts, respectively. Patients showed lower Z-scores at DXA than controls (p<0.05) when considering the entire case load and both NS and CFCS groups. Vitamin D and Calcitonin levels were significantly lower (p< 0.01), Parathormone levels significantly higher (p<0.05) in patients compared to the control group (p<0.05). Patients with lower BMD showed reduced physical activity and joint pain. Finally, anti-TPO antibody levels were significantly higher in patients than in controls when considering the entire case load and both NS and CFCS groups.Conclusions: The collected data demonstrate a high prevalence of thyroid autoimmunity, confirming an increased risk to develop autoimmune disorders both in NS and CFCS. Reduced BMD, probably associated to reduced physical activity and inflammatory cytokines, also occurs. These findings are expected to have implications for the follow-up and prevention of osteopenia/ osteoporosis in both NS and CFCS. [ABSTRACT FROM AUTHOR]

Background: Abnormalities of the immune system are rarely reported in patients affected by RASopathies. Aim of the current study was to investigate the prevalence of immune system dysfunction in a cohort of patients affected by RASopathies.Study Design: A group of 69 patients was enrolled: 60 at the Federico II University, Naples, 7 at University Magna Graecia of Catanzaro, 2 at "Scuola Medica Salernitana", Salerno. An age- and sex-matched control group was also enrolled. Autoimmune disorders were investigated according to international consensus criteria. Immune framework was also evaluated by immunoglobulin levels, CD3, CD4, CD8, CD19, CD56 lymphocyte subpopulations, autoantibodies levels and panel of inflammatory molecules, in both patients and controls.Results: Frequent upper respiratory tract infections were recorded in 2 patients; pneumonia, psoriasis and alopecia in single patients. Low IgA levels were detected in 8/44 patients (18.18%), low CD8 T cells in 13/35 patients (37.14%). Anti-tg and anti-TPO antibodies were detected in 3/24 patients (12.5%), anti r-TSH in 2 cases (8.33%), all in euthyroidism. Serum IgA and CD8 levels were significantly lower in patients than in controls (p 0.00685; p 0.000656 respectively). All tested patients showed increased inflammatory molecules compared to controls. These findings may anticipate the detection of overt autoimmune disease.Conclusions: Patients affected by RASopathies are at risk to develop autoimmune disorders. Routine screening for autoimmunity is recommended in patients with RASopathy. [ABSTRACT FROM AUTHOR]

Aurora kinase A (AURKA) is a conserved kinase that plays crucial roles in numerous cellular processes. Although AURKA overexpression is frequent in human cancers, its pleiotropic functions and multifaceted regulation present challenges in its therapeutic targeting. Key to overcoming these challenges is to identify and characterize the full range of AURKA interactors, which are often weak and transient. Previous proteomic studies were limited in monitoring dynamic and non‐mitotic AURKA interactions. Here, we generate the proximity interactome of AURKA in asynchronous cells, which consists of 440 proteins involving multiple biological processes and cellular compartments. Importantly, AURKA has extensive proximate and physical interactions to centriolar satellites, key regulators of the primary cilium. Loss‐of‐function experiments identify satellites as negative regulators of AURKA activity, abundance, and localization in quiescent cells. Notably, loss of satellites activates AURKA at the basal body, decreases centrosomal IFT88 levels, and causes ciliogenesis defects. Collectively, our results provide a resource for dissecting spatiotemporal regulation of AURKA and uncover its proteostatic regulation by satellites as a new mechanism for its ciliary functions. SYNOPSIS: This study presents the in vivo proximity interactome of AURKA in asynchronous cells, which reveals a new regulatory and functional relationship between AURKA and centriolar satellites. AURKA proximity interactome is composed of 440 proteins involving diverse biological processes and cellular compartments.AURKA has extensive interactions with centriolar satellite proteins.Depletion of centriolar satellites increases cellular and centrosomal abundance and activation of AURKA.AURKA inhibition rescues the ciliogenesis defects of cells depleted for centriolar satellites. [ABSTRACT FROM AUTHOR]

Postzygotic mutations of the PIK3CA [phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha] gene constitutively activate the PI3K/AKT/mTOR pathway in PIK3CA-related overgrowth spectrum (PROS) patients, causing congenital mosaic tissue overgrowth that even multiple surgeries cannot solve. mTOR inhibitors are empirically tested and given for compassionate use in these patients. PROS patients could be ideal candidates for enrolment in trials with PI3K/AKT pathway inhibitors, considering the “clean” cellular setting in which a unique driver, a PIK3CA mutation, is present. We aimed to assess the effects of blocking the upstream pathway of mTOR on PROS patient-derived cells by using ARQ 092, a potent, selective, allosteric, and experimental orally bioavailable and highly selective AKT-inhibitor with activity and long-term tolerability, currently under clinical development for treatment of cancer and Proteus syndrome. Cell samples (i.e., primary fibroblasts) were derived from cultured tissues obtained from six PROS patients [3 boys, 3 girls; aged 2 to 17 years] whose spectrum of PIK3A-related overgrowth included HHML [hemihyperplasia multiple lipomatosis; n = 1], CLOVES [congenital lipomatosis, overgrowth, vascular malformations, epidermal nevi, spinal/skeletal anomalies, scoliosis; n = 1], and MCAP [megalencephaly capillary malformation syndrome; n = 4]. We performed the following: (a) a deep sequencing assay of PI3K/AKT pathway genes in the six PROS patients’ derived cells to identify the causative mutations and (b) a pathway analysis to assess the phosphorylation status of AKT [Ser473 and Thr308] and its downstream targets [pAKTS1 (Thr246), pRPS6 (Ser235/236), and pRPS6Kβ1 (Ser371)]. The anti-proliferative effect of ARQ 092 was tested and compared to other PI3K/AKT/mTOR inhibitors [i.e., wortmannin, LY249002, and rapamycin] in the six PROS patient-derived cells. Using ARQ 092 to target AKT, a critical node connecting PI3K and mTOR pathways, we observed the following: (1) strong anti-proliferative activity [ARQ 092 at 0.5, 1, and 2.5 μM blunted phosphorylation of AKT and its downstream targets (in the presence or absence of serum) and inhibited proliferation after 72 h; rapamycin at 100 nM did not decrease AKT phosphorylation] and (2) less cytotoxicity as compared to rapamycin and wortmannin. We demonstrated the following: (a) that PROS cells are dependent on AKT; (b) the advantage of inhibiting the pathway immediately downstream of PI3K to circumventing problems depending on multiple classes a PI3K kinases; and (c) that PROS patients benefit from inhibition of AKT rather than mTOR. Clinical development of ARQ 092 in PROS patients is on going in these patients. [ABSTRACT FROM AUTHOR]

Coordination between membrane trafficking and actin polymerization is fundamental in cell migration, but a dynamic view of the underlying molecular mechanisms is still missing. The Rac1 GTPase controls actin polymerization at protrusions by interacting with its effector, the Wave regulatory complex (WRC). The exocyst complex, which functions in polarized exocytosis, has been involved in the regulation of cell motility. Here, we show a physical and functional connection between exocyst and WRC. Purified components of exocyst and WRC directly associate in vitro, and interactions interfaces are identified. The exocyst-WRC interaction is confirmed in cells by co-immunoprecipitation and is shown to occur independently of the Arp2/3 complex. Disruption of the exocyst-WRC interaction leads to impaired migration. By using time-lapse microscopy coupled to image correlation analysis, we visualized the trafficking of the WRC towards the front of the cell in nascent protrusions. The exocyst is necessary for WRC recruitment at the leading edge and for resulting cell edge movements. This direct link between the exocyst and WRC provides a new mechanistic insight into the spatio-temporal regulation of cell migration. [ABSTRACT FROM AUTHOR]

We provide data on fetal growth pattern on the molecular subtypes of Beckwith-Wiedemann syndrome ( BWS): IC1 gain of methylation ( IC1-GoM), IC2 loss of methylation ( IC2-LoM), 11p15.5 paternal uniparental disomy ( UPD), and CDKN1C mutation. In this observational study, gestational ages and neonatal growth parameters of 247 BWS patients were compared by calculating gestational age-corrected standard deviation scores ( SDS) and proportionality indexes to search for differences among IC1-GoM ( n = 21), UPD ( n = 87), IC2-LoM ( n = 147), and CDKN1C mutation ( n = 11) patients. In IC1-GoM subgroup, weight and length are higher than in other subgroups. Body proportionality indexes display the following pattern: highest in IC1-GoM patients, lowest in IC2-LoM/ CDKN1C patients, intermediate in UPD ones. Prematurity was significantly more prevalent in the CDKN1C (64%) and IC2-LoM subgroups (37%). Fetal growth patterns are different in the four molecular subtypes of BWS and remarkably consistent with altered gene expression primed by the respective molecular mechanisms. IC1-GoM cases show extreme macrosomia and severe disproportion between weight and length excess. In IC2-LoM/ CDKN1C patients, macrosomia is less common and associated with more proportionate weight/length ratios with excess of preterm birth. UPD patients show growth patterns closer to those of IC2-LoM, but manifest a body mass disproportion rather similar to that seen in IC1-GoM cases. [ABSTRACT FROM AUTHOR]

Background: Glycogen storage disease type 1 (GSD1) is a rare and genetically heterogeneous metabolic defect of gluconeogenesis due to mutations of either the G6PC gene (GSD1a) or the SLC37A4 gene (GSD1b). Osteopenia is a known complication of GSD1. Objectives: The aim of this study was to investigate the effects of poor metabolic control and/or use of GSD1-specific treatments on bone mineral density (BMD) and metabolism in GSD1 patients. Methods: In a multicenter, cross-sectional case-control study, we studied 38 GSD1 (29 GSD1a and 9 GSD1b) patients. Clinical, biochemical and instrumental parameters indicative of bone metabolism were analyzed; BMD was evaluated by dual-emission X-ray absorptiometry and quantitative ultrasound. Results: Both GSD1a and GSD1b patients showed reduced BMD compared with age-matched controls. In GSD1a patients, these abnormalities correlated with compliance to diet and biochemical indicators of metabolic control. In GSD1b patients, BMD correlated with the age at first administration and the duration of granulocyte colony-stimulating factor (G-CSF) therapy. Conclusions: Our data indicate that good metabolic control and compliance with diet are highly recommended to improve bone metabolism in GSD1a patients. GSD1b patients on G-CSF treatment should be carefully monitored for the risk of osteopenia/osteoporosis. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Noonan-like syndrome with loose anagen hair (NS/LAH; OMIM 607721), recently related to the invariant c.4A>G missense change in SHOC2, is characterized by features reminiscent of Noonan syndrome. Ectodermal involvement, short stature associated with growth hormone (GH) deficiency (GHD), and cognitive deficits are common features. We report on a patient with molecularly confirmed NS/LAH exhibiting severe short stature associated with GH insensitivity (GHI), and chronic complex tics, a neurological feature never described before in this syndrome. IGF1 generation test revealed only a blunted increase in IGF1 after exogenous GH treatment, revealing mild GH insensitivity associated with proper STAT5 activation. Most common causes of secondary tics in childhood were excluded. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background: Neutropenia and/or neutrophil dysfunction are part of glycogen storage disease type 1b (GSD1b) phenotype. Recent studies indicated that activation of apoptosis and increased reactive oxygen species are implicated in the pathogenesis of neutropenia in GSD1b.Methods: We studied seven GSD1b patients over a 2-year-period to evaluate the efficacy of vitamin E, a known antioxidant, in preventing or improving the clinical manifestations associated with neutropenia and neutrophil dysfunction. Frequency and severity of infections, neutrophil counts and function, ileocolonoscopy and intestinal histology, were monitored. During the first year, patients did not assume vitamin E; during the second year of the study, vitamin E supplementation was added to their therapeutic regimens.Results: During vitamin E supplementation, the mean values of neutrophil counts were significantly higher (p < 0.05) and neutrophil counts lower than 500/mm(3) were found less frequently (p < 0.05); the frequency and severity of infections, mouth ulcers and perianal lesions, was reduced (p < 0.05); ileocolonoscopy and histology showed a mild improvement. Vitamin E supplementation did not result in changes in neutrophil function.Conclusions: These results suggest that vitamin E supplementation might be beneficial in GSD1b patients and may alleviate disease manifestations associated with neutropenia. [ABSTRACT FROM AUTHOR]

Glycogen storage disease type Ib (GSD Ib, OMIM 232220) is an inborn disorder of glucose metabolism, caused by mutations in the G6PT gene, encoding a glucose 6-phosphate transporter (G6PT). GSD Ib is mainly associated with fasting hypoglycaemia and hepatomegaly. Most GSD Ib patients also show neutropenia and neutrophil dysfunction and therefore are at risk of developing severe infections and inflammatory bowel disease (IBD). An increased risk for autoimmune disorders, such as thyroid autoimmunity and Crohn-like disease, has also been demonstrated, but no systematic study on the prevalence of autoimmune disorders in GSD Ib patients has ever been performed. We describe a 25-year-old patient affected by GSD Ib who developed 'seronegative' myasthenia gravis (MG), presenting with bilateral eyelid ptosis, diplopia, dysarthria, severe dysphagia, dyspnoea and fatigue. The repetitive stimulation of peripheral nerves test showed signs of exhaustion of neuromuscular transmission, particularly evident in the cranial area. Even in the absence of identifiable anti-acetylcholine receptor antibodies, seronegative MG is considered an autoimmune disorder and may be related to the disturbed immune function observed in GSD Ib patients. [ABSTRACT FROM AUTHOR]

We describe three patients with type A Niemann-Pick disease (NPD-A). NPD-A is an autosomal recessive neuronal storage disease classified among the sphingolipidoses, characterized by accumulation of sphingomyelin in various tissues and in the brain. Magnetic Resonance imaging (MRI) of our three patients showed a marked delay of myelination with frontal atrophy. Few descriptions of this MRI pattern of delayed myelination have been published to date. [ABSTRACT FROM AUTHOR]

Estimated glomerular filtration rate (eGFR) predicts mortality in non-diabetic populations, but its role in people with type 2 diabetes is unknown. We assessed to what extent a reduction in eGFR in people with type 2 diabetes predicts 11-year all-cause and cardiovascular mortality, independently of AER and other cardiovascular risk factors. The study population was the population-based cohort (n = 1,538; median age 68.9 years) of the Casale Monferrato Study. GFR was estimated by the abbreviated Modification of Diet in Renal Disease Study equation. At baseline, the prevalence of chronic kidney disease (eGFR <60 ml min−1 1.73 m−2) was 34.3% (95% CI 33.0–36.8). There were 670 deaths in 10,708 person-years of observation. Hazard ratios of 1.23 (95% CI 1.03–1.47) for all-cause mortality and 1.18 (95% CI 0.92–1.52) for cardiovascular mortality were observed after adjusting for cardiovascular risk factors and AER. When five levels of eGFR were analysed we found that most risk was conferred by eGFR 15–29 ml min−1 1.73 m−2, whereas no increased risk was evident in people with eGFR values between 30 and 59 ml min−1 1.73 m−2. In an analysis stratified by AER categories, a significant increasing trend in risk with decreasing eGFR was evident only in people with macroalbuminuria. Our study suggests that in type 2 diabetes macroalbuminuria is the main predictor of mortality, independently of both eGFR and cardiovascular risk factors, whereas eGFR provides no further information in normoalbuminuric people. [ABSTRACT FROM AUTHOR]

The efficacy of ACE-inhibitors in decreasing microalbuminuria and proteinuria has been reported in a few patients with glycogen storage disease type 1 (GSD1); however, no case-control study has ever been published. The aim of the current study was to evaluate the efficacy of ACE-inhibitors in reducing glomerular hyperfiltration, microalbuminuria and proteinuria, and in delaying the progression of renal damage. Ninety-five patients (median age at the time of the study: 14·5 years) were enrolled from nine Italian referral centres for metabolic diseases. A retrospective study of a 10-year follow-up was conducted in order to compare the evolution of these parameters in treated patients with those who were not treated with ACE-inhibitors. A significant and progressive decrease of glomerular filtration rate was observed in treated patients vs. those who were not treated with ACE-inhibitors ( P < 0·05). No difference was observed for microalbuminuria and proteinuria between the two groups of patients. Moreover, the ACE-inhibitors significantly delayed the progression from glomerular hyperfiltration to microalbuminuria, but not that from microalbuminuria to proteinuria. The results of the present study underline the importance of a strict follow-up of renal function in GSD1 patients. The detection of glomerular hyperfiltration suggests precocious initiation of ACE-inhibitor treatment to delay the progression of renal damage. A randomized prospective study is needed to establish for certain the real effectiveness of this treatment in GSD1 patients. [ABSTRACT FROM AUTHOR]

Summary: Deficiency of a microsomal phosphate transporter in the liver has been suggested in some patients affected by glycogen storage disease type Ic (GSD Ic). Several Na+/phosphate co-transporters have been characterized as members of the anion-cation symporter family. Recently, the cDNA sequence of two phosphate transporters, NPT3 and NPT4, expressed in liver, kidney and intestine, has been determined. We studied expression of human NPT4 in COS cells and observed an ER localization of the transporter by immunofluorescence microscopy. We speculated that this transporter could play a role in the regulation of the glucose-6-phosphatase (G6-Pase) complex. We revealed the genomic structure of NPT4 and analysed the gene as a candidate for GSD Ic. DNA was collected from five patients without mutations in G6-Pase or the G6-P transporter gene. DNA analysis of NPT4 revealed that one patient was heterozygous for a G>A transition at nucleotide 601 which would result in a G201R substitution. Our results do not confirm the hypothesis that this gene is mutated in GSD Ic patients. However, we cannot exclude that the mutation found reduces the phosphate transport efficiency, possibly modulating the G6-Pase complex. [ABSTRACT FROM AUTHOR]

Aim: To investigate the presence of inflammatory bowel disease (IBD) and to evaluate the progression of bowel involvement after two years' follow-up in seven patients affected by glycogen storage disease type Ib (GSDIb).Methods: Seven patients (5F, 2M, aged 4.5-20.6 y) entered the study. Bowel involvement was evaluated by ileocolonoscopy and specific IBD serologic markers. To evaluate disease activity, Paediatric Crohn's Disease Activity Index (PCDAI), terminal ileum wall thickness detected at ultrasonography (US), 99mTechnetium labelled autologous White Cell Scan (Tc-WCS) and barium meal with follow-through were investigated.Results: Ileocolonoscopy and histology examination revealed variable degrees of bowel involvement in all patients. The results of serologic markers were indicative of a Crohn's-like ileocolitis. US and Tc-WCS, could clearly define patients with severe inflammatory involvement, but failed to identify all patients with mild to moderate disease. For the most severely affected patients, anti-inflammatory agents and steroids were prescribed, whereas nutritional therapy with polymeric formula and antibiotics were assumed by two other patients and antibiotics only by one patient. Granulocyte colony-stimulating factor (G-CSF) was prescribed to all patients. Ileocolonoscopy and histology data improved in all patients. The assumption of G-CSF and/or gastric drip feeding (g.d.f.) was inversely associated with the PCDAI results (p < 0.05).Conclusion: IBD is common in patients affected by GSDIb independently of the severity of gastrointestinal signs and symptoms. Different therapeutic approaches can be used according to the severity of IBD. G-CSF treatment and g.d.f. can be protective factors for IBD. [ABSTRACT FROM AUTHOR]

Centrosomes function in key cellular processes ranging from cell division to cellular signaling. Their dysfunction is linked to cancer and developmental disorders. Here, we identify CCDC57 as a pleiotropic regulator of centriole duplication, mitosis, and ciliogenesis. Combining proximity mapping with superresolution imaging, we show that CCDC57 localizes to the proximal end of centrioles and interacts with the microcephaly protein CEP63, centriolar satellite proteins, and microtubules. Loss of CCDC57 causes defects in centriole duplication and results in a failure to localize CEP63 and CEP152 to the centrosome. Additionally, CCDC57 depletion perturbs mitotic progression both in wild-type and centriole-less cells. Importantly, its centrosome-targeting region is required for its interaction with CEP63 and functions during centriole duplication and cilium assembly, whereas the microtubule-targeting region is required for its mitotic functions. Together, our results identify CCDC57 as a critical interface between centrosome and microtubule-mediated cellular processes that are deregulated in microcephaly. • CCDC57 localizes to pericentriolar material, microtubules, and satellites • CCDC57 co-localizes with CEP63 at the proximal end of centrioles • CCDC57 binds to CEP63 and functions during initiation of centriole duplication • CCDC57 interacts with microtubules and ensures proper mitotic progression Centrosome dysfunction is linked to cancer and neurodevelopmental disorders such as primary microcephaly. Gurkaslar et al. identify CCDC57 as a pleiotropic regulator of centriole duplication, mitosis, and ciliogenesis. They show that it mediates its functions by regulating recruitment of centriole duplication proteins to the centrosome and microtubule nucleation. [ABSTRACT FROM AUTHOR]

We report on a 21 month old child referred to us because of facial dysmorphism and psychomotor retardation. The patient's phenotype was characterised by a wide and receding forehead, broad nasal bridge, redundant retronuchal skin, low set and poorly shaped ears, micrognathia, and small hands and feet. High resolution R and G banding karyotype analysis of peripheral blood lymphocytes showed an interstitial deletion of the long arm of chromosome 1 spanning bands q22 to q24. The cytogenetic results were confirmed by molecular analysis. The phenotype observed in our patient was relatively milder than those reported in other patients with an interstitial deletion of chromosome 1q. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented regarding splice-site mutations in CHD7 gene in two patients with CHARGE syndrome (CS) phenotype.

Glycogenosis type III (Cori disease) is an autosomal recessive disorder caused by the deficiency of the glycogen debranching enzyme, encoded by the AGL gene, and existing in six isoforms alternately spliced in a tissue-specific way. Generally, disease onset occurs early on starting from the first year of life, with hepatomegaly, hypoglycemia, hyperlipidemia, increased CK levels, and, in some cases, short stature and slight mental retardation. Frequently, hepatomegaly tends to resolve spontaneously and inexplicably during childhood, when myopathy, often associated with cardiomyopathy, arises. This disease is known to lack almost invariably clear links between the genotype and clinical phenotype. We describe nine new mutations in Italian patients: four nonsense (p.Arg285X, p.Lys422X, p.Arg910X, p.Arg977X), three frameshift (c.442delA, c.753_756delGACA, c.3963delG), and two missense (p.Ala1120Pro, p.Arg524His). Particularly, the nonsense p.Arg285X is linked to an exonic splicing enhancer and it was found to produce two species of transcripts at the same time. Moreover, we discuss a subgroup of subjects carrying c.2681+1G>A, which has proven to be the most frequent mutation among our patients. The previously described c.664+3A>G was also detected in two patients, both homozygous. The present work is yet another confirmation that the individual genetic background plays a pivotal role in influencing the phenotypes, as occurs in other metabolic diseases. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]