Loredana Cavalli

The Negative Feedback-Loop between the Oncomir Mir-24-1 and Menin Modulates the Men1 Tumorigenesis by Mimicking the “Knudson’s Second Hit”

Multiple endocrine neoplasia type 1 (MEN1) syndrome is a rare hereditary cancer disorder characterized by tumors of the parathyroids, of the neuroendocrine cells, of the gastro-entero-pancreatic tract, of the anterior pituitary, and by non-endocrine neoplasms and lesions. MEN1 gene, a tumor suppressor gene, encodes menin protein. Loss of heterozygosity at 11q13 is typical of MEN1 tumors, in agreement with the Knudson’s two-hit hypothesis. In silico analysis with Target Scan, Miranda and Pictar-Vert softwares for the prediction of miRNA targets indicated miR-24-1 as capable to bind to the 3′UTR of MEN1 mRNA. We investigated this possibility by analysis of miR-24-1 expression profiles in parathyroid adenomatous tissues from MEN1 gene mutation carriers, in their sporadic non-MEN1 counterparts, and in normal parathyroid tissue. Interestingly, the MEN1 tumorigenesis seems to be under the control of a “negative feedback loop” between miR-24-1 and menin protein, that mimics the second hit of Knudson’s hypothesis and that could buffer the effect of the stochastic factors that contribute to the onset and progression of this disease. Our data show an alternative way to MEN1 tumorigenesis and, probably, to the “two-hit dogma”. The functional significance of this regulatory mechanism in MEN1 tumorigenesis is also the basis for opening future developments of RNA antagomir(s)-based strategies in the in vivo control of tumorigenesis in MEN1 carriers.

Multiple endocrine neoplasia type 1 (MEN1): Not only inherited endocrine tumors

Abstract: MEN 1 is a rare hereditary cancer syndrome which manifests a variety of endocrine and non-endocrine neoplasms and lesions. Growing knowledge of this condition in both its molecular genetic underpinnings and its clinical implications have affected the entire spectrum of the clinical management of MEN patients. The MEN1 gene is a tumor suppressor gene, and mutations in it account for the development of the MEN1 clinical syndrome through impairment of several cell functions, such as cell proliferations, cell growth control, apoptosis, DNA replication and repair, gene expression, transcriptional machinery control, and hormone secretion. Currently, DNA testing makes possible the early identification of germline mutations in asymptomatic mutation carriers. The ever increrasing combination of genetic and clinical tools will allow early detection of MEN1-associated neoplasms, potentially improving clinical outcomes and quality of life for both affected patients and their relatives.

Hereditary hyperparathyroidism syndromes.

Primary hyperparathyroidism is a common endocrine disorder, resulting from a persistent hypercalcemia along with an inadequate secretion of parathyroid hormone. In approx 95% of cases, it occurs sporadically; rarely, it is part of familial syndromes. These inherited syndromes typically present at an earlier age than the nonheritable form and occur with equal frequencies in both sexes. The differential diagnosis is often difficult, but it is of fundamental importance for the management of patients and their family. The availability of specific genetic tests has improved the diagnostic accuracy allowing early diagnosis in asymptomatic family members. Before the advent of genetic testing, a definitive diagnosis could be made only in symptomatic cases based on clinical data and family history.

Vitamin D levels in children, adolescents, and young adults with juvenile-onset systemic lupus erythematosus: a cross-sectional study.

Background SS and LC contributed equally to this manuscript. Hypovitaminosis D is common in the general population. Although many studies on 25-hydroxyvitamin D (25(OH)D) are available on systemic lupus erythematosus (SLE), few data are reported in juvenile-onset SLE (JSLE) patients. Design This study aimed to assess serum 25(OH)D levels in JSLE patients and to identify risk factors for vitamin D deficiency in this population. Methods Forty-five Caucasian JSLE patients (36 females, nine males; mean age 18.9 ± 6.3 years) and 109 age- and sex-matched healthy controls entered the study. Dual-energy X-ray absorptiometry (DXA) scans of the lumbar spine, serum calcium and phosphate, bone-specific alkaline phosphatase (BSAP), parathyroid hormone (PTH), and 25(OH)D were assessed. The data were compared with an age- and sex-matched control group including 109 Caucasian healthy subjects. Results JSLE patients exhibited lower 25(OH)D levels than controls (p < 0.005), with the lower values observed in patients with active vs. inactive disease (p < 0.05). JSLE patients exhibited reduced total calcium levels (p < 0.001) and higher phosphate levels (p < 0.001), BSAP (p < 0.001) and PTH (p < 0.001) than controls. In addition, JSLE patients exhibited lower spine bone mineral apparent density (BMAD) SDS values than controls (p < 0.001), with higher values in patients with 25(OH)D sufficiency and insufficiency than in those with 25(OH)D deficiency (p < 0.001). Conclusions Patients with JSLE have significantly lower 25(OH)D levels than controls. Therefore, vitamin D supplementation may be useful to normalize bone mass and quality in subjects with JSLE.

Cinacalcet in the management of primary hyperparathyroidism: post marketing experience of an Italian multicentre group.

To report the Italian experience on cinacalcet use following its approval by the European Medical Agency (EMA) to control hypercalcaemia in patients with primary hyperparathyroidism (PHPT).

Cross-sectional and longitudinal evaluation of bone mass and quality in children and young adults with juvenile onset systemic lupus erythematosus (JSLE): role of bone mass determinants analyzed by DXA, PQCT and QUS

Introduction Stefano Stagi and Loredana Cavalli contributed equally to the manuscript; Maria Luisa Brandi and Fernanda Falcini contributed equally to the manuscript. There are few prospective data on bone mass and quality in patients with juvenile onset systemic lupus erythematosus (JSLE). There are also few studies analyzing bone mass and quality determinants by using at the same time dual-energy X-ray absorptiometry (DXA), peripheral quantitative computed tomography (pQCT) and quantitative ultrasound (QUS). Objective The objective of this paper is to evaluate cross-sectionally and longitudinally bone mass and quality determinants in adolescents and young adults with JSLE, and to identify the main predictors of reduced bone mineral density (BMD) and bone quality using these techniques. Methods Fifty-six patients with JSLE (mean age 18.5 ± 5.7 years) entered the study. In all subjects DXA scan at the lumbar spine, radius pQCT and phalangeal QUS were performed the same day. Of these, 46 patients (mean age 23.1 ± 6.2 years) were revaluated with a second DXA, pQCT and QUS. The data obtained were compared with 72 and 80 age- and sex- matched healthy controls. Results At the first evaluation, JSLE patients had a reduced spine BMAD SDS (p < 0.001), and significantly lower levels of TrabBMD (p < 0.0001), SSIp (p < 0.05), AD-SoS and QUS z-score (p < 0.005) but not reduced muscleCSA and CBA values. CortBMD and FatCSA were significantly increased (p < 0.0001). These data were confirmed at longitudinal evaluation regarding spine BMAD SDS (p < 0.001), TrabBMD (p < 0.0001), FatCSA (p < 0.005), AD-SoS (p < 0.001), and QUS z-score (p < 0.005) but not muscle CSA (p ≤ 0.05) and CBA (p < 0.0001). SSIp and CortBMD longitudinal evaluation showed that JSLE patients did not present significant differences in comparison to controls. Conclusions Patients with JSLE have a low bone mass without catch-up growth over time, causing a reduction of peak bone mass with high risk of osteoporosis in early adulthood. To reduce the risk, close monitoring of BMD, better control of disease activity, physical activity and dietary intake of calcium and vitamin D are advocated to ameliorate the loss of bone mass. In patients with proved osteoporosis therapeutic approaches including bisphosphonates should be considered.

DNA-based test: when and why to apply it to primary hyperparathyroidism clinical phenotypes

Several cancer‐related genes have been discovered and molecular test for the cancer genetic risk assessment has been widely increasing. Disorders such as Multiple Endocrine Neoplasia syndromes have received benefits from the identification of the responsible genes whose mutations account for the genetic susceptibility to develop endocrine tumours. Primary hyperparathyroidism (PHPT)is a clinical phenotype frequently associated to Multiple Endocrine Neoplasia syndromes, but it can also represent the unique endocrinopathy recurring as a familial cluster. In recent years, care options have been made available to patients and families with hereditary PHPT, and the process of systematically assessing the genetic risk has been becoming increasingly important. This review aims to help health providers not frequently dealing with genetic testing use and it will introduce some general concepts concerning genetic diagnosis issues. As an example the role and the practical usefulness of DNA‐based diagnosis in patients affected by different forms of congenital PHPT is described, with a close look on why, when and how genetic testing should be performed in these subjects and their relatives. Some practical recommendations and suggestions concerning on how to deal when a suspect or known case of familial PHPT has to be faced conclude this manuscript.

Determinants of Vitamin D Levels in Children, Adolescents, and Young Adults with Juvenile Idiopathic Arthritis

Objective. Deficiency of 25-hydroxyvitamin D [25(OH)D] is reported to be common in patients with rheumatoid arthritis (RA); data in patients with juvenile idiopathic arthritis (JIA) are inconsistent. We assessed serum 25(OH)D in children, adolescents and young adults with JIA, in order to identify the risk factors for vitamin D deficiency in patients with JIA. Methods. We evaluated 152 patients with JIA: 115 female, 37 male, mean age 16.2 ± 7.4 yrs; evaluated by onset type, 96 had oligoarticular, 35 polyarticular, 7 systemic, and 14 enthesitis-related arthritis (ERA). Patients were compared with a control group matched for sex and age. All patients and controls underwent laboratory tests of plasma 25(OH)D, parathyroid hormone (PTH), calcium, phosphorus, and bone alkaline phosphatase levels, and dual-energy x-ray absorptiometry examination. Results. Patients with JIA showed significantly reduced 25(OH)D levels compared to controls (p < 0.001), even divided into subtypes (oligoarticular, p < 0.05; polyarticular, p < 0.005; systemic, p < 0.001; ERA, p < 0.005). Patients with active disease and/or frequent relapses had significantly reduced 25(OH)D levels compared to patients with no active disease and no frequent flares (p < 0.005, respectively). Nevertheless, JIA patients had significantly higher PTH levels compared to controls (p < 0.0001). JIA patients with 25(OH)D deficiency showed a significantly lower bone mineral apparent density than those with normal 25(OH)D levels (p < 0.001). Conclusion. JIA patients have reduced 25(OH)D and higher PTH values. This may explain at least in part why JIA patients, despite more effective current drugs, do not achieve bone-normal condition over time. JIA patients with more severe disease could require higher supplementation of vitamin D to maintain normal 25(OH)D serum levels. Longterm studies are needed to investigate the relationship between serum 25(OH)D levels and disease activity in JIA.

Targeted approaches in the treatment of osteoporosis: differential mechanism of action of denosumab and clinical utility.

Denosumab is a breakthrough biological drug approved by the Food and Drug Administration and European Medicines Agency for the treatment of osteoporosis in 2010. It is a fully human monoclonal antireceptor activator of nuclear factor kappa-B ligand antibody, which inhibits the activity of osteoclasts, resulting in an antiresorptive effect with a significant increase in bone mineral density. The FREEDOM (Fracture Reduction Evaluation of Denosumab in Osteoporosis every 6 Months) trial, comparing denosumab with no treatment in 7868 women with postmenopausal osteoporosis, showed an important reduction of fracture risk at hip, vertebral, and nonvertebral sites in the treated group, while no statistically significant difference in the incidence of adverse events was detected between denosumab and placebo groups. The specific action of denosumab directed against a key regulator of osteoclasts makes it a valuable tool in preventing the occurrence of skeletal events caused by bone destruction in patients with advanced malignancies. The drug was approved for postmenopausal osteoporosis in women at increased risk of fracture and for the treatment of bone loss associated with androgen deprivation therapy in men with prostate cancer.

Peripheral quantitative computed tomography (pQCT) for the assessment of bone strength in most of bone affecting conditions in developmental age: a review

Peripheral quantitative computed tomography provides an automatical scan analysis of trabecular and cortical bone compartments, calculating not only their bone mineral density (BMD), but also bone geometrical parameters, such as marrow and cortical Cross-Sectional Area (CSA), Cortical Thickness (CoTh), both periosteal and endosteal circumference, as well as biomechanical parameters like Cross-Sectional Moment of Inertia (CSMI), a measure of bending, polar moment of inertia, indicating bone strength in torsion, and Strength Strain Index (SSI). Also CSA of muscle and fat can be extracted. Muscles, which are thought to stimulate bones to adapt their geometry and mineral content, are determinant to preserve or increase bone strength; thus, pQCT provides an evaluation of the functional ‘muscle-bone unit’, defined as BMC/muscle CSA ratio. This functional approach to bone densitometry can establish if bone strength is normally adapted to the muscle force, and if muscle force is adequate for body size, providing more detailed insights to targeted strategies for the prevention and treatment of bone fragility. The present paper offers an extensive review of technical features of pQCT and its possible clinical application in the diagnostic of bone status as well as in the monitoring of the skeleton’s health follow-up.