Comparative proteomic expression profile in all-trans retinoic acid differentiated neuroblastoma cell line

Neuroblastoma (NB) is an infant tumor which frequently differentiates into neurons. We used twodimensional differential in-gel electrophoresis (2D-DIGE) to analyze the cytosolic and nuclear protein expression patterns of LAN-5 cells following neuronal differentiating agent all-trans-retinoic acid treatment. We identified several candidate proteins, from which Gβ2 and Prefoldin 3 may have a role on NB development. These results strength the use of proteomics to discover new putative protein targets in cancer. Keywords

The MURAVES muon telescope: technology and expected performances

The MURAVES project aims to study the inner structure of the upper part of the Mt. Vesuvius volcano by muon radiography (muography) technique. Very high energy muons, produced by cosmic rays in the at- mosphere, can penetrate large thickness of rocks. By measuring the at- tenuation of the muons flux trough the volcano cone is possible to obtain a 2D image of the density structure. Internal discontinuities, with a spa- tial resolution of about 10 m, can be, in principle, resolved. An absolute average density measurement can be provided too. The project, funded by the Italian Ministry of University, Research and Education (MIUR), is led by INGV and INFN. In this article the mechanical structure of the de- tectors and background suppression techniques are reported

Common genetic variants in NEFL influence gene expression and neuroblastoma risk

The genetic etiology of sporadic neuroblastoma is still largely obscure. In a genome-wide association study, we identified single-nucleotide polymorphisms (SNP) associated with neuroblastoma at the CASC15, BARD1, LMO1, DUSP12, HSD17B12, HACE1, and LIN28B gene loci, but these explain only a small fraction of neuroblastoma heritability. Other neuroblastoma susceptibility genes are likely hidden among signals discarded by the multiple testing corrections. In this study, we evaluated eight additional genes selected as candidates for further study based on proven involvement in neuroblastoma differentiation. SNPs at these candidate genes were tested for association with disease susceptibility in 2,101 cases and 4,202 controls, with the associations found replicated in an independent cohort of 459 cases and 809 controls. Replicated associations were further studied for cis-effect using gene expression, transient overexpression, silencing, and cellular differentiation assays. The neurofilament gene NEFL harbored three SNPs associated with neuroblastoma (rs11994014: Pcombined \ubc 0.0050; OR, 0.88; rs2979704: Pcombined \ubc 0.0072; OR, 0.87; rs1059111: Pcombined \ubc 0.0049; OR, 0.86). The protective allele of rs1059111 correlated with increased NEFL expression. Biologic investigations showed that ectopic overexpression of NEFL inhibited cell growth specifically in neuroblastoma cells carrying the protective allele. NEFL overexpression also enhanced differentiation and impaired the proliferation and anchorage-independent growth of cells with protective allele and basal NEFL expression, while impairing invasiveness and proliferation of cells homozygous for the risk genotype. Clinically, high levels of NEFL expression in primary neuroblastoma specimens were associated with better overall survival (P \ubc 0.03; HR, 0.68). Our results show that common variants of NEFL influence neuroblastoma susceptibility and they establish that NEFL expression influences disease initiation and progressio

Morphology of the toe flexor muscles in older people with toe deformities

Objective: Despite suggestions that atrophied, or weak toe flexor muscles are associated with the formation of toe deformities, there has been little evidence to support this theory. This study aimed to determine whether the size of the toe flexor muscles differed in older people with and without toe deformities. Methods: Forty-four older adults (>60 years) were recruited for the study. Each participant had their feet assessed for the presence of hallux valgus or lesser toe deformities. Intrinsic and extrinsic toe flexor muscles were imaged with an ultrasound system using a standardised protocol. Assessor blinded muscle thickness and cross-sectional area was measured using Image J software. Results: Participants with lesser toe deformities (n=20) were found to have significantly smaller quadratus plantae (p=0.003), flexor digitorum brevis (p=0.013), abductor halluces (p=0.004) and flexor halluces brevis (p=0.005) muscles than the participants without any toe deformities (n=19). Female participants with hallux valgus (n=10) were found to have significantly smaller abductor hallucis (p=0.048) and flexor halluces brevis (p=0.013) muscles than the female participants without any toe deformities (n=10; p<0.05). Conclusion: This is the first study to use ultrasound to investigate the size of the toe flexor muscles in older people with hallux valgus and lesser toe deformities compared to otherwise healthy older adults. The size of the abductor hallucis and flexor hallucis brevis muscles were decreased in participants with hallux valgus whereas the quadratus plantae, flexor digitorum brevis, abductor hallucis and flexor halluces brevis muscles were smaller in those participants with lesser toe deformities

Discovery of new therapeutic targets in Neuroblastoma by means of proteomic approach and functional studies

Neuroblatoma (NB) is an embryonal tumor of the sympathetic nervous system which arises from the neural crest cells. This disease rappresents the most common extracranial tumor in infants, accounting for 8% to 10% of all childhood cancer and for approximately 15% of cancer deaths in children. NB is a heterogeneous tumor for which biology dictates clinical behaviour. It comprises cases with divergent outcome ranging from spontaneous differentiation to metastatic forms with poor prognosis. The deep knowledge of NB biology is imperative toward the development of novel therapy. The most favourable subset of NB (stage 4S) can spontaneously differentiate in neurons or regress to a benign tumour phenotype. Retinoic Acid (RA) is a known neural differentiation-inducing agent actually used in NB therapy. In order to get new insights in the molecular mechanism driving neuronal differentiation in vitro, two-Dimensional Differential In-Gel Electrophoresis (2D-DIGE) analyse was performed on the cytosolic and nuclear protein expression patterns of NB cells following RA treatment. The combination of a proteomic approach and sub-cellular fractionation of the proteome provides the identification of 33 differentially expressed proteins during RA treatment in NB. The identified proteins have important roles in a variety of pathways which may have role on NB development and in NB RA-induced differentiation. The results also strength the use of proteomics to discover new putative protein targets in cancer. Expression of Trk receptors is an important prognostic factor in NB. TrkB and its ligand BDNF (brain derived neurotrophin factor) are preferentially expressed in NB with poor prognosis, conferring invasive and metastatic potential to the tumor cells as well as enhancing therapy resistance. TrkA in contrast is high expressed in tumor with good outcome. Galectin-1 (Gal-1), a very promising cancer target, is involved in modulating cell proliferation, cell death and cell migration and was found to be up-regulated in patients with aggressive, relapsing NB. Gal-1 is a down-stream mediator of TrkB signalling, since its espression is increased in human SY5Y NB cells upon activation of ectopically expressed TrkB (SY5Y-TrkB), but not TrkA (SY5Y-TrkA). Functional studies here presented underlined the Gal-1 role to mediate invasion and migration in TrkB over-expressing NB cells, thus being activated by BDNF. This establishes Gal-1 as a potential therapeutic marker in high-risk TrkB-expressing NB

Inhibition of hypoxia inducible factors combined with all-trans retinoic acid treatment enhances glial transdifferentiation of neuroblastoma cells

Neuroblastoma (NBL) is a heterogeneous tumor characterized by a wide range of clinical manifestations. A high tumor cell differentiation grade correlates to a favorable stage and positive outcome. Expression of the hypoxia inducible factors HIF1-α (HIF1A gene) and HIF2-α (EPAS1 gene) and/or hypoxia-regulated pathways has been shown to promote the undifferentiated phenotype of NBL cells. Our hypothesis is that HIF1A and EPAS1 expression represent one of the mechanisms responsible for the lack of responsiveness of NBL to differentiation therapy. Clinically, high levels of HIF1A and EPAS1 expression were associated with inferior survival in two NBL microarray datasets, and patient subgroups with lower expression of HIF1A and EPAS1 showed significant enrichment of pathways related to neuronal differentiation. In NBL cell lines, the combination of all-trans retinoic acid (ATRA) with HIF1A or EPAS1 silencing led to an acquired glial-cell phenotype and enhanced expression of glial-cell differentiation markers. Furthermore, HIF1A or EPAS1 silencing might promote cell senescence independent of ATRA treatment. Taken together, our data suggest that HIF inhibition coupled with ATRA treatment promotes differentiation into a more benign phenotype and cell senescence in vitro. These findings open the way for additional lines of attack in the treatment of NBL minimal residue disease

HIF-1 transcription activity: HIF1A driven response in normoxia and in hypoxia

Abstract Background HIF1A (Hypoxia-Inducible-Factor 1A) expression in solid tumors is relevant to establish resistance to therapeutic approaches. The use of compounds direct against hypoxia signaling and HIF1A does not show clinical efficiency because of changeable oxygen concentrations in solid tumor areas. The identification of HIF1A targets expressed in both normoxia and hypoxia and of HIF1A/hypoxia signatures might meliorate the prognostic stratification and therapeutic successes in patients with high-risk solid tumors. Methods In this study, we conducted a combined analysis of RNA expression and DNA methylation of neuroblastoma cells silenced or unsilenced for HIF1A expression, grown in normoxia and hypoxia conditions. Results The analysis of pathways highlights HIF-1 (heterodimeric transcription factor 1) activity in normoxia in metabolic process and HIF-1 activity in hypoxia in neuronal differentiation process. HIF1A driven transcriptional response in hypoxia depends on epigenetic control at DNA methylation status of gene regulatory regions. Furthermore, low oxygen levels generate HIF1A-dependent or HIF1A-independent signatures, able to stratify patients according to risk categories. Conclusions These findings may help to understand the molecular mechanisms by which low oxygen levels reshape gene signatures and provide new direction for hypoxia targeting in solid tumor