Sterol profiles in plasma and erythrocyte membranes in patients with Smith-Lemli-Opitz syndrome: a six-year experience

Background: This study reports our experience over the last six years in the diagnosis of Smith-Lemli-Opitz syndrome and other inborn errors of cholesterol biosynthesis. Methods: Gas chromatography/mass spectrometry was used to obtain sterol profiles in plasma and erythrocyte membranes of suspected patients. Results: Plasma sterol reference values calculated in unaffected subjects (ns276) were in agreement with those previously reported. Among patients investigated from 2005 to 2010, we report 16 patients affected by Smith-Lemli-Opitz syndrome, three of whom represent new cases and 13 of whom were follow-up patients. In this period we also identified a new case of chondrodysplasia punctata 2 X-linked. The estimated incidence obtained for Smith-Lemli-Opitz syndrome was 1:93 suspected patients (1.08%). We also studied the effect of storage on the dehydrocholesterols/ cholesterol ratio in plasma and erythrocyte membranes of patients affected by Smith-Lemli-Opitz syndrome stored at –208C for up to 22 and 20 months, respectively. A significant negative linear correlation between storage time and the dehydrocholesterols/cholesterol ratio was identified in both plasma and erythrocyte membranes. The decrease in the dehydrocholesterols/cholesterol ratio in erythrocyte membranes was at least two-fold higher than in plasma. Conclusions: The results of this study may be helpful for diagnosis and interpretation of data in patients with findings suggestive of a cholesterol biosynthesis defect

Diagnostic criteria and tumor screening for individuals with isolated hemihyperplasia

Isolated hemihyperplasia, formerly termed isolated hemihypertrophy, is a congenital overgrowth disorder associated with an increased risk for embryonal tumors, mainly Wilms tumor and hepatoblastoma. This practice guideline will set forth the diagnostic criteria and tumor screening recommendations for children with isolated hemihyperplasia, based on the best information available. There is clinical overlap between isolated hemihyperplasia with Beckwith-Wiedemann syndrome. The majority of Beckwith-Wiedemann syndrome patients have a molecular abnormality involving the imprinted cluster of genes at 11p15.5. In contrast, the preponderance of isolated hemihyperplasia patients studied have no identified etiology. Tumors have developed in isolated hemihyperplasia patients with and without molecular abnormalities. For this reason, molecular diagnostics are not helpful in identifying the subset of isolated hemihyperplasia patients with tumor risk and all isolated hemihyperplasia patients should undergo tumor screening

POS0424 DETERMINING CIRCULATING ENDOTHELIAL CELLS USING CELLSEARCH SYSTEM IN SYSTEMIC SCLEROSIS PATIENTS

Background:Endothelial damage and fibroproliferative vasculopathy of small vessels are pathological hallmarks of Systemic Sclerosis (SSc). Detection and analysis of circulating endothelial cells (CECs) detached from affected blood vessels may be an informative tool to study vascular dysfunction and could be considered a novel biomarker of scleroderma vasculopathy. Our group first showed the presence of CECs in SSc by fluorescence-activated cell sorting (FACS), demonstrating that a raised counts of active CECs may represent direct evidence of active vascular disease in SSc. Despite these interesting data, issues related to difficulties in CEC counting through FACS analysis, due their very low concentration in peripheral blood, prevented further investigations in this field. Recently, a specific kit for the detection of CECs has been developed through the CellSearch System (CS), a semi-automated device for the standardized analysis of rare cells, such as CECs, in peripheral blood.Objectives:To assess the counts of CECs determined by the CS in SSc patients and to evaluate their clinical implication and potential as vascular biomarker in SSc.Methods:10mL of blood samples were collected from 29 subjects (19 SSc patients and 10 healthy donors - HDs) and stored in tubes containing a specific preservative, to allow the analysis of 4mL of blood within 72 hours, according to manufacturer instructions. Out of 19 SSc patients, 18 were female, 10 had the limited form and 9 the diffuse cutaneous variant of SSc. CS uses a proprietary kit containing a ferrofluid-based reagent, that target CD146 to magnetically capture CECs, and the immunofluorescent reagents to stain the CECs, defined as CD146+, CD105-PE+, DAPI+ and CD45-APC-. Clinical, laboratoristic and demographic data were also collected.Results:The mean number of CECs in patients with SSc was significantly higher in comparison to HDs (554/4mL vs. 53.5/4 mL, p=0.0042). When analyzed according to disease subset, both lcSSc and dcSSc showed significantly increased levels of CECs in comparison with HDs (p=0.003 and p=0.005, respectively). No statistical difference was observed in the mean number of CECs in patients with lcSSc compared to those with dcSSc. Regarding vascular involvement, the CECs counts strictly correlated with the presence of digital ulcers (DUs) (p=0.0001) showing a median of 863cells/4mL for the SSc patients with DUs versus a median of 276.2/4mL for the SSc patients without DUs. No statistical correlation was found between CECs and serological autoantibody pattern, skin parameters, or joint and muscle involvement. Patients with active disease, according to the EUSTAR Activity Index, showed a higher CECs value than those with inactive disease (p=0.0012).Conclusion:The amount of CECs detectable in peripheral blood has been recently proposed as a marker of endothelial damage in different vascular diseases, including SSc. However, currently no standardized method is available to determine CEC counts, which makes reported data on CECs reliable and suitable. The CS system is a commercially available semi-automated system that enables standardized determination of CECs. Thus, we examined clinical utility of CECs count by this system in SSc patients. Our results confirm that baseline CEC counts, evaluated by a new standardized method, may represent direct evidence of endothelial damage in SSc and could be a promising tool for monitoring active disease and evaluating therapeutic responses to vascular and immunosuppressive treatments.References:[1]Del Papa N, Pignataro F. Front Immunol. 2018 Jun 18;9:1383[2]De Simone C et al. J Eur Acad Dermatol Venereol. 2014 May;28(5):590-6[3]Del Papa N et al. Arthritis Rheum. 2004 Apr;50(4):1296-304Disclosure of Interests:Francesca Pignataro: None declared, Laura Zorzino: None declared, Wanda Maglione: None declared, Antonina Minniti: None declared, Giulia Clericuzio: None declared, Marco Picozzi: None declared, Cecilia Simonelli Employee of: Menarini Silicon Biosystems, Francesco Picardo Employee of: Menarini Silicon Biosystems, Roberto Caporali: None declared, Nicoletta Del Papa: None declare

Germline mutations in the oncogene EZH2 cause Weaver syndrome and increased human height.

The biological processes controlling human growth are diverse, complex and poorly understood. Genetic factors are important and human height has been shown to be a highly polygenic trait to which common and rare genetic variation contributes. Weaver syndrome is a human overgrowth condition characterised by tall stature, dysmorphic facial features, learning disability and variable additional features. We performed exome sequencing in four individuals with Weaver syndrome, identifying a mutation in the histone methyltransferase, EZH2, in each case. Sequencing of EZH2 in additional individuals with overgrowth identified a further 15 mutations. The EZH2 mutation spectrum in Weaver syndrome shows considerable overlap with the inactivating somatic EZH2 mutations recently reported in myeloid malignancies. Our data establish EZH2 mutations as the cause of Weaver syndrome and provide further links between histone modifications and regulation of human growth

Structural Characterisation of Metabolites from Pholiota spumosa (Basidiomycetes)

Three compounds of different biosynthetic origin were isolated from the fruiting bodies of the gilled mushroom Pholiota spumosa (Basidiomycetes, Strophariaceae). Fasciculol E, a lanostane triterpenoid conjugated to a depsipeptide unit, was isolated for the first time from genus Pholiota. In addition, the first isolation of putrescine-1,4-dicinnamamide as a natural compound is reported: its structure was established by single crystal X-ray diffraction, and by spectroscopic methods. Crystallographic analysis indicated the presence of a co-crystallised related dicinnamamide, namely the new compound (E)-2,3-dehydroputrescine-1,4-dicinnamamide, whose occurrence was confirmed by LC-MS analysis. An interesting evolutionary issue arises, following the observation that the cinnamamides produced by Pholiota spumosa bear an unsubstituted benzene ring, contrarily to those found in plants, which have always phenolic functionalities, and as such perform a variety of biological roles