Head and neck paragangliomas, rare neoplasms of the paraganglia composed of nests of neurosecretory and glial cells embedded in vascular stroma, provide a remarkable example of organoid tumor architecture. To identify genes and pathways commonly deregulated in head and neck paraganglioma, we integrated high-density genome-wide copy number variation (CNV) analysis with microRNA and immunomorphological studies. Gene-centric CNV analysis of 24 cases identified a list of 104 genes most significantly targeted by tumor-associated alterations. The “NOTCH signaling pathway” was the most significantly enriched term in the list (P = 0.002 after Bonferroni or Benjamini correction). Expression of the relevant NOTCH pathway proteins in sustentacular (glial), chief (neuroendocrine) and endothelial cells was confirmed by immunohistochemistry in 47 head and neck paraganglioma cases. There were no relationships between level and pattern of NOTCH1/JAG2 protein expression and germline mutation status in the SDH genes, implicated in paraganglioma predisposition, or the presence/absence of immunostaining for SDHB, a surrogate marker of SDH mutations. Interestingly, NOTCH upregulation was observed also in cases with no evidence of CNVs at NOTCH signaling genes, suggesting altered epigenetic modulation of this pathway. To address this issue we performed microarray-based microRNA expression analyses. Notably 5 microRNAs (miR-200a,b,c and miR-34b,c), including those most downregulated in the tumors, correlated to NOTCH signaling and directly targeted NOTCH1 in in vitro experiments using SH-SY5Y neuroblastoma cells. Furthermore, lentiviral transduction of miR-200s and miR-34s in patient-derived primary tympano-jugular paraganglioma cell cultures was associated with NOTCH1 downregulation and increased levels of markers of cell toxicity and cell death. Taken together, our results provide an integrated view of common molecular alterations associated with head and neck paraganglioma and reveal an essential role of NOTCH pathway deregulation in this tumor type.Electronic supplementary materialThe online version of this article (doi:10.1007/s00401-013-1165-y) contains supplementary material, which is available to authorized users.
AimThe aim of the study was to investigate whether human megakaryocytic cells have an adaptive response to aspirin treatment, leading to an enhancement of multidrug resistance protein-4 (MRP4) expression in circulating platelets responsible for a reduced aspirin action. We recently found that platelet MRP4 overexpression has a role in reducing aspirin action in patients after by-pass surgery. Aspirin enhances MRP4-mRNA levels in rat liver and drug administration transcriptionally regulates MRP4 gene expression through peroxisome proliferator-activated receptor-α (PPARα).MethodsThe effects induced by aspirin or PPARα agonist (WY14643) on MRP4 modulation were evaluated in vitro in a human megakaryoblastic DAMI cell line, in megakaryocytes (MKs) and in platelets obtained from human haematopoietic progenitor cell (HPC) cultures, and in vivo platelets obtained from aspirin treated healthy volunteers (HV).ResultsIn DAMI cells, aspirin and WY14643 treatment induced a significant increase in MRP4 and PPARα expression. In human MKs grown in the presence of either aspirin or WY14643, MRP4 and PPARα-mRNA were higher than in control cultures and derived platelets showed an enhancement in MRP4 protein expression. The ability of aspirin to modulate MRP4 expression in MKs and to transfer it to platelets was also confirmed in vivo. In fact, we found the highest MRP4 mRNA and protein expression in platelets obtained from HV after 15 days' aspirin treatment.ConclusionsThe present study provides evidence, for the first time, that aspirin treatment affects the platelet protein pattern through MK genomic modulation. This work represents an innovative and attractive approach, useful both to identify patients less sensitive to aspirin and to improve pharmacological treatment in cardiovascular high-risk patients.
The development of thrombotic obstruction in the portal bed of cirrhotic patients presents special problems in diagnosis and treatment. In the cirrhotic population treated for portal hypertension at our Surgical Department during the period 1967-1983 (512 patients), the incidence of thrombosis in the portal bed was 16.6% (85 patients). Bleeding was the main presenting symptom (70/85), with a mean of four episodes prior to treatment. Careful angiographic studies and intraoperative evaluation are fundamental steps to determine the exact anatomical involvement, the presence of recanalized veins or fresh occluding clots, and the applicability of shunt procedures. A massive portosplenomesenteric involvement often associated with poor surgical possibilities was found in 19 patients (22.3%). The presence of partially recanalized veins and fresh occluding clot suitable for disobliterative techniques prior to shunt was found in 16 patients, and out of 73 operated patients a total of 55 shunt procedures could be performed. Fifty-three patients who bled from varices could be followed up to 5 years: 39 underwent a shunt procedure with a 51.2% 5-year survival rate, while only one of 14 nonshunted or nonoperated survived up to 3 years, and a lethal bleeding was the cause of death in all but one. Disobliterative techniques (Fogarty thrombectomy and endovenectomy of intimal fibrotic thickenings) prior to shunting provided a good long-term patency rate with a 50% protection from lethal bleeding recurrences. Nonshunt procedures and the extensive involvement of the portal bed are associated with bad prognosis. Also, endoscopic sclerotherapy, attempted in patients with massive thrombosis, could not prevent recurrences and death from bleeding. Despite a 30% failure rate in our study, shunting surgery should be considered the only therapeutical possibility of preventing further thrombotic recurrences and consequent life threatening bleeding episodes.
OBJECTIVES During the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) pandemic, Northern Italy had to completely reorganize its hospital activity. In Lombardy, the hub-and-spoke system was introduced to guarantee emergency and urgent cardiovascular surgery, whereas most hospitals were dedicated to patients with coronavirus disease 2019 (COVID-19). The aim of this study was to analyse the results of the hub-and-spoke organization system. METHODS Centro Cardiologico Monzino (Monzino) became one of the four hubs for cardiovascular surgery, with a total of eight spokes. SARS-CoV-2 screening became mandatory for all patients. New flow charts were designed to allow separated pathways based on infection status. A reorganization of spaces guaranteed COVID-19-free and COVID-19-dedicated areas. Patients were also classified into groups according to their pathological and clinical status: emergency, urgent and non-deferrable (ND). RESULTS A total of 70 patients were referred to the Monzino hub-and-spoke network. We performed 41 operations, 28 (68.3%) of which were emergency/urgent and 13 of which were ND. The screening allowed the identification of COVID-19 (three patients, 7.3%) and non-COVID-19 patients (38 patients, 92.7%). The newly designed and shared protocols guaranteed that the cardiac patients would be divided into emergency, urgent and ND groups. The involvement of the telematic management heart team allowed constant updates and clinical discussions. CONCLUSIONS The hub-and-spoke organization system efficiently safeguards access to heart and vascular surgical services for patients who require ND, urgent and emergency treatment. Further reorganization will be needed at the end of this pandemic when elective cases will again be scheduled, with a daily increase in the number of operations.
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