180 research outputs found

    A Drosophila protein-interaction map centered on cell-cycle regulators

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    BACKGROUND: Maps depicting binary interactions between proteins can be powerful starting points for understanding biological systems. A proven technology for generating such maps is high-throughput yeast two-hybrid screening. In the most extensive screen to date, a Gal4-based two-hybrid system was used recently to detect over 20,000 interactions among Drosophila proteins. Although these data are a valuable resource for insights into protein networks, they cover only a fraction of the expected number of interactions. RESULTS: To complement the Gal4-based interaction data, we used the same set of Drosophila open reading frames to construct arrays for a LexA-based two-hybrid system. We screened the arrays using a novel pooled mating approach, initially focusing on proteins related to cell-cycle regulators. We detected 1,814 reproducible interactions among 488 proteins. The map includes a large number of novel interactions with potential biological significance. Informative regions of the map could be highlighted by searching for paralogous interactions and by clustering proteins on the basis of their interaction profiles. Surprisingly, only 28 interactions were found in common between the LexA- and Gal4-based screens, even though they had similar rates of true positives. CONCLUSIONS: The substantial number of new interactions discovered here supports the conclusion that previous interaction mapping studies were far from complete and that many more interactions remain to be found. Our results indicate that different two-hybrid systems and screening approaches applied to the same proteome can generate more comprehensive datasets with more cross-validated interactions. The cell-cycle map provides a guide for further defining important regulatory networks in Drosophila and other organisms

    Acute subdural hematoma in the elderly. outcome analysis in a retrospective multicentric series of 213 patients

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    OBJECTIVE: The objective of this study was to analyze the risk factors associated with the outcome of acute subdural hematoma (ASDH) in elderly patients treated either surgically or nonsurgically. METHODS: The authors performed a retrospective multicentric analysis of clinical and radiological data on patients aged ≥ 70 years who had been consecutively admitted to the neurosurgical department of 5 Italian hospitals for the management of posttraumatic ASDH in a 3-year period. Outcome was measured according to the Glasgow Outcome Scale (GOS) at discharge and at 6 months' follow-up. A GOS score of 1-3 was defined as a poor outcome and a GOS score of 4-5 as a good outcome. Univariate and multivariate statistics were used to determine outcome predictors in the entire study population and in the surgical group. RESULTS: Overall, 213 patients were admitted during the 3-year study period. Outcome was poor in 135 (63%) patients, as 65 (31%) died during their admission, 33 (15%) were in a vegetative state, and 37 (17%) had severe disability at discharge. Surgical patients had worse clinical and radiological findings on arrival or during their admission than the patients undergoing conservative treatment. Surgery was performed in 147 (69%) patients, and 114 (78%) of them had a poor outcome. In stratifying patients by their Glasgow Coma Scale (GCS) score, the authors found that surgery reduced mortality but not the frequency of a poor outcome in the patients with a moderate to severe GCS score. The GCS score and midline shift were the most significant predictors of outcome. Antiplatelet drugs were associated with better outcomes; however, patients taking such medications had a better GCS score and better radiological findings, which could have influenced the former finding. Patients with fixed pupils never had a good outcome. Age and Charlson Comorbidity Index were not associated with outcome. CONCLUSIONS: Traumatic ASDH in the elderly is a severe condition, with the GCS score and midline shift the stronger outcome predictors, while age per se and comorbidities were not associated with outcome. Antithrombotic drugs do not seem to negatively influence pretreatment status or posttreatment outcome. Surgery was performed in patients with a worse clinical and radiological status, reducing the rate of death but not the frequency of a poor outcome

    Frataxin participates to the hypoxia-induced response in tumors

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    Defective expression of frataxin is responsible for the degenerative disease Friedreich's ataxia. Frataxin is a protein required for cell survival since complete knockout is lethal. Frataxin protects tumor cells against oxidative stress and apoptosis but also acts as a tumor suppressor. The molecular bases of this apparent paradox are missing. We therefore sought to investigate the pathways through which frataxin enhances stress resistance in tumor cells. We found that frataxin expression is upregulated in several tumor cell lines in response to hypoxic stress, a condition often associated with tumor progression. Moreover, frataxin upregulation in response to hypoxia is dependent on hypoxia-inducible factors expression and modulates the activation of the tumor-suppressor p53. Importantly, we show for the first time that frataxin is in fact increased in human tumors in vivo. These results show that frataxin participates to the hypoxia-induced stress response in tumors, thus implying that modulation of its expression could have a critical role in tumor cell survival and/or progression

    Preliminary experience with 4K ultra-high definition endoscope: analysis of pros and cons in skull base surgery

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    Negli ultimi venti anni la chirurgia endoscopica del basicranio ha osservato continui sviluppi tecnici e tecnologici. Lendoscopia 3D e l alta definizione (HD) 4K hanno fornito grandi vantaggi in termini di visualizzazione e di risoluzione spaziale. L ultra HD 4K, recentemente introdotta nella pratica clinica, determinerà i prossimi passi soprattutto nella chirurgica endoscopica del basicranio. I pazienti sono stati operati attraverso un approccio transnasale transfenoidale endoscopico, utilizzando un endoscopio Olympus NBI 4K UHD con ottica 4 mm 0 ° Ultra Telescope, lampada allo xeno 300 W (CLV-S400) predisposto per la tecnologia narrow band imaging (NBI) collegato con una videocamera ad un alta qualità unità di controllo (OTV-S400 - VISERA 4K UHD) (Olympus, Tokyo, Giappone). Due schermi, un 31 Monitor - (LMD-X310S) e quello principale ultra-HD 55 a pollici ottimizzati per la riproduzione immagini UHD (LMD-X550S). In casi selezionati abbiamo usato un sistema di navigazione (Stealthstation S7, Medtronic, Minneapolis, MN, Stati Uniti). Abbiamo valutato 22 adenomi ipofisari (86,3% macroadenomi; 13,7% microadenomi). Il 50% non erano secernenti (NS), 22,8% GH, 18,2% ACTH, 9% PRLsecernenti. 3/22 erano recidive. Nel 91% dei casi abbiamo raggiunto la rimozione totale, mentre nel 9% la resezione subtotale. Un followup medio di 187 giorni, durata media del ricovero era 3,09 ± 0,61 giorni. Tempo chirurgico 128,18 ± 30,74 minuti. Abbiamo avuto solo 1 caso di fistola intraoperatoria a basso flusso senza ulteriori complicazioni nel follow up. Il 100% dei casi non ha richiesto emotrasfusione. La visualizzazione e lalta risoluzione del campo operatorio hanno fornito una vista dettagliata di tutte le strutture anatomiche e patologie e permesso il miglioramento della sicurezza e lefficacia della procedura chirurgica. Il tempo operatorio è stato simile a quello dellendoscopio HD standard 2D e 3D, come la fatica fisica era paragonabile ad altri in termini di ergonomicità e peso

    Phospho-mTOR expression in human glioblastoma microglia-macrophage cells

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    The glioblastoma (GBM) immune microenvironment is highly heterogeneous, and microglia may represent 30–70% of the entire tumor. However, the role of microglia and other specific immune populations is poorly characterized. Activation of mTOR signaling occurs in numerous human cancers and has roles in microglia-glioma cell interactions. We now show in human tumor specimens (42 patients), that 39% of tumor-associated microglial (TAM) cells express mTOR phosphorylated at Ser-2448; and similar mTOR activation is observed using a human microglia-glioma interaction paradigm. In addition, we confirm previous studies that microglia express urea and ARG1 (taken as M2 marker) in the presence of glioma cells, and this phenotype is down-regulated in the presence of a mTOR inhibitor. These results suggest that mTOR suppression in GBM patients might induce a reduction of the M2 phenotype expression in up to 40% of all TAMs. Since the M2 profile of microglial activation is believed to be associated with tumor progression, reductions in that phenotype may represent an additional anti-tumor mechanism of action of mTOR inhibitors, along with direct anti-proliferative activities

    Detection of ctDNA in plasma of patients with clinically localised prostate cancer is associated with rapid disease progression.

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    BACKGROUND DNA originating from degenerate tumour cells can be detected in the circulation in many tumour types, where it can be used as a marker of disease burden as well as to monitor treatment response. Although circulating tumour DNA (ctDNA) measurement has prognostic/predictive value in metastatic prostate cancer, its utility in localised disease is unknown. METHODS We performed whole-genome sequencing of tumour-normal pairs in eight patients with clinically localised disease undergoing prostatectomy, identifying high confidence genomic aberrations. A bespoke DNA capture and amplification panel against the highest prevalence, highest confidence aberrations for each individual was designed and used to interrogate ctDNA isolated from plasma prospectively obtained pre- and post- (24 h and 6 weeks) surgery. In a separate cohort (n = 189), we identified the presence of ctDNA TP53 mutations in preoperative plasma in a retrospective cohort and determined its association with biochemical- and metastasis-free survival. RESULTS Tumour variants in ctDNA were positively identified pre-treatment in two of eight patients, which in both cases remained detectable postoperatively. Patients with tumour variants in ctDNA had extremely rapid disease recurrence and progression compared to those where variants could not be detected. In terms of aberrations targeted, single nucleotide and structural variants outperformed indels and copy number aberrations. Detection of ctDNA TP53 mutations was associated with a significantly shorter metastasis-free survival (6.2 vs. 9.5 years (HR 2.4; 95% CIs 1.2-4.8, p = 0.014). CONCLUSIONS CtDNA is uncommonly detected in localised prostate cancer, but its presence portends more rapidly progressive disease

    Cancer stem cells from peritumoral tissue of glioblastoma multiforme: the possible missing link between tumor development and progression.

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    In glioblastoma multiforme (GBM), cancer stem cells (CSCs) are thought to be responsible for gliomagenesis, resistance to treatment and recurrence. Unfortunately, the prognosis for GBM remains poor and recurrence frequently occurs in the peritumoral tissue within 2 cm from the tumor edge. In this area, a population of CSCs has been demonstrated which may recapitulate the tumor after surgical resection. In the present study, we aimed to characterize CSCs derived from both peritumoral tissue (PCSCs) and GBM (GCSCs) in order to deepen their significance in GBM development and progression. The stemness of PCSC/GCSC pairs obtained from four human GBM surgical specimens was investigated by comparing the expression of specific stem cell markers such as Nestin, Musashi-1 and SOX2. In addition, the growth rate, the ultrastructural features and the expression of other molecules such as c-Met, pMet and MAP kinases, involved in cell migration/invasion, maintenance of tumor stemness and/or resistance to treatments were evaluated. Since it has been recently demonstrated the involvement of the long non-coding RNAs (lncRNAs) in the progression of gliomas, the expression of H19 lncRNA, as well as of one of its two mature products miR-675-5p was evaluated in neurospheres. Our results show significant differences between GCSCs and PCSCs in terms of proliferation, ultrastructural peculiarities and, at a lower extent, stemness profile. These differences might be important in view of their potential role as a therapeutic target

    Subgroup Economic Analysis for Glioblastoma in a Health Resource-Limited Setting

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    BACKGROUND: The aim of this research was to evaluate the economic outcomes of radiotherapy (RT), temozolomide (TMZ) and nitrosourea (NT) strategies for glioblastoma patients with different prognostic factors. METHODOLOGY/PRINCIPAL FINDINGS: A Markov model was developed to track monthly patient transitions. Transition probabilities and utilities were derived primarily from published reports. Costs were estimated from the perspective of the Chinese healthcare system. The survival data with different prognostic factors were simulated using Weibull survival models. Costs over a 5-year period and quality-adjusted life years (QALYs) were estimated. Probabilistic sensitivity and one-way analyses were performed. The baseline analysis in the overall cohort showed that the TMZ strategy increased the cost and QALY relative to the RT strategy by 25,328.4and0.29,respectively;andtheTMZstrategyincreasedthecostandQALYrelativetotheNTstrategyby25,328.4 and 0.29, respectively; and the TMZ strategy increased the cost and QALY relative to the NT strategy by 23,906.5 and 0.25, respectively. Therefore, the incremental cost effectiveness ratio (ICER) per additional QALY of the TMZ strategy, relative to the RT strategy and the NT strategy, amounts to 87,940.6and87,940.6 and 94,968.3, respectively. Subgroups with more favorable prognostic factors achieved more health benefits with improved ICERs. Probabilistic sensitivity analyses confirmed that the TMZ strategy was not cost-effective. In general, the results were most sensitive to the cost of TMZ, which indicates that better outcomes could be achieved by decreasing the cost of TMZ. CONCLUSIONS/SIGNIFICANCE: In health resource-limited settings, TMZ is not a cost-effective option for glioblastoma patients. Selecting patients with more favorable prognostic factors increases the likelihood of cost-effectiveness

    Prostate cancer cell-intrinsic interferon signaling regulates dormancy and metastatic outgrowth in bone

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    The latency associated with bone metastasis emergence in castrate-resistant prostate cancer is attributed to dormancy, a state in which cancer cells persist prior to overt lesion formation. Using single-cell transcriptomics and ex vivo profiling, we have uncovered the critical role of tumor-intrinsic immune signaling in the retention of cancer cell dormancy. We demonstrate that loss of tumor-intrinsic type I IFN occurs in proliferating prostate cancer cells in bone. This loss suppresses tumor immunogenicity and therapeutic response and promotes bone cell activation to drive cancer progression. Restoration of tumor-intrinsic IFN signaling by HDAC inhibition increased tumor cell visibility, promoted long-term antitumor immunity, and blocked cancer growth in bone. Key findings were validated in patients, including loss of tumor-intrinsic IFN signaling and immunogenicity in bone metastases compared to primary tumors. Data herein provide a rationale as to why current immunotherapeutics fail in bone-metastatic prostate cancer, and provide a new therapeutic strategy to overcome the inefficacy of immune-based therapies in solid cancers.Katie L Owen, Linden J Gearing, Damien J Zanker, Natasha K Brockwell, Weng Hua Khoo, Daniel L Roden, Marek Cmero, Stefano Mangiola, Matthew K Hong, Alex J Spurling, Michelle McDonald, Chia-Ling Chan, Anupama Pasam, Ruth J Lyons, Hendrika M Duivenvoorden, Andrew Ryan, Lisa M Butler, John M Mariadason, Tri Giang Phan, Vanessa M Hayes, Shahneen Sandhu, Alexander Swarbrick, Niall M Corcoran, Paul J Hertzog, Peter I Croucher, Chris Hovens, Belinda S Parke
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