The EphA2 receptor drives self-renewal and tumorigenicity in stem-like tumor-propagating cells from human glioblastomas

In human glioblastomas (hGBMs), tumor-propagating cells with stem-like characteristics (TPCs) represent a key therapeutic target. We found that the EphA2 receptor tyrosine kinase is overexpressed in hGBM TPCs. Cytofluorimetric sorting into EphA2(High) and EphA2(Low) populations demonstrated that EphA2 expression correlates with the size and tumor-propagating ability of the TPC pool in hGBMs. Both ephrinA1-Fc, which caused EphA2 downregulation in TPCs, and siRNA-mediated knockdown of EPHA2 expression suppressed TPCs self-renewal ex vivo and intracranial tumorigenicity, pointing to EphA2 downregulation as a causal event in the loss of TPCs tumorigenicity. Infusion of ephrinA1-Fc into intracranial xenografts elicited strong tumor-suppressing effects, suggestive of therapeutic applications.

Post-traumatic hydrocephalus after decompressive craniectomy: an underestimated risk factor

The incidence of post-traumatic hydrocephalus (PTH) has been reported to be 0.7-51.4%, and we have frequently observed the development of PTH in patients undergoing decompressive craniectomy (DC). For this reason we performed a retrospective review of a consecutive series of patients undergoing DC after traumatic brain injury (TBI). From January 2006 to December 2009, 41 patients underwent DC after closed head injury. Study outcomes focused specifically on the development of hydrocephalus after DC. Variables described by other authors to be associated with PTH were studied, including advanced age, the timing of cranioplasty, higher score on the Fisher grading system, low post-resuscitation Glasgow Coma Scale (GCS) score, and cerebrospinal fluid (CSF) infection. We also analyzed the influence of the area of craniotomy and the distance of craniotomy from the midline. Logistic regression was used with hydrocephalus as the primary outcome measure. Of the nine patients who developed hydrocephalus, eight patients (89%) had undergone craniotomy with the superior limit <25 mm from the midline. This association was statistically significant (p = 0.01 - Fisher's exact test). Logistic regression analysis showed that the only factor independently associated with the development of hydrocephalus was the distance from the midline. Patients with craniotomy whose superior limit was <25 mm from the midline had a markedly increased risk of developing hydrocephalus (OR = 17). Craniectomy with a superior limit too close to the midline can predispose patients undergoing DC to the development of hydrocephalus. We therefore suggest performing wide DCs with the superior limit >25 mm from the midline.

Lipid nanoparticles for intranasal administration: application to nose-to-brain delivery

INTRODUCTION

The blood brain barrier is a functional barrier allowing the entry into the brain of only essential nutrients, excluding other molecules. Its structure, although essential to keep the harmful entities out, is also a major roadblock for pharmacological treatment of brain diseases. Several alternative invasive drug delivery approaches, such as transcranial drug delivery and disruption of blood brain barrier have been explored, with limited success and several challenges. Intranasal delivery is a non-invasive methodology, which bypasses the systemic circulation, and, through the intra- and extra- neuronal pathways, provides direct brain drug delivery. Colloidal drug delivery systems, particularly lipidic nanoparticles offer several unique advantages for this goal.

AREAS COVERED

This review focuses on key brain diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis, and provide a detailed overview of the current lipid nanoparticle based treatment options explored thus far. The review also delves into basic preparation, challenges and evaluation methods of lipid drug delivery systems.

EXPERT OPINION

Brain diseases present complex pathophysiology, in addition to the practically inaccessible brain tissues, hence according to the authors, a two-pronged approach utilizing new target discovery coupled with new drug delivery systems such as lipid carriers must be adopted.

Cranial repair: how complicated is filling a "hole"?

In general, cranioplasty is viewed as a straightforward surgical procedure, and for many years the complications associated with the procedure have been underestimated. We reviewed our 5-year experience consisting of 218 cranioplasties. Study outcomes focused specifically on the occurrence of complications after cranioplasty. Autologous bone-assisted and prosthetic cranioplasties were considered. Variables described by other authors to be associated with complications were studied, including history of previous cranioplasty, wider craniectomy size, bifrontal craniectomy, and delayed cranioplasty. We also analyzed the influence of material used for craniectomy on the occurrence of complications. The overall complication rate was 19.7%. Nineteen cases of infection (8.7%), 5 cases of postoperative wound dehiscence (2.3%), 6 cases of epidural hemorrhage (2.8%), and 13 cases of cranioplasty dislocation (5.9%) were observed. Bifrontal cranioplasties were more frequently associated with complications (p=0.01; Fisher's exact test) and infection (p<0.0001; Fisher's exact test). Postoperative wound dehiscence was more frequently observed with hand-made or custom-made cranioplasties compared with autologous cranioplasties (p=0.02). Early cranioplasty (<3 months from craniectomy) was significantly associated with cranioplasty dislocation (p=0.03). Logistical regression analysis showed that the only factor independently associated with complication was the site of cranioplasty (p=0.01). In particular, patients with a bifrontal cranioplasty had a 2-fold increased risk of complication (CI 95 1.1-3.6, p=0.017) and a 2.5-fold increased risk of developing infection (CI 95 1.3-4.9, p=0.009) compared with hemispheric/bihemispheric cranioplasty. Our analysis confirms that cranioplasty is burdened by a significant complication rate. In this context, bifrontal cranioplasty is related to a higher risk of complication and, in particular, infection.

The influence of surgery on recurrence pattern of glioblastoma

OBJECTIVES

Glioblastoma recurs within 2 cm from the primary tumor's margins in 90-95% of cases. Natural history of recurrence is not well defined. The aim of this study was to verify if pattern of recurrence can be influenced by the extent of surgery.

PATIENTS AND METHODS

131 patients with glioblastoma underwent tumor removal, followed by standard adjuvant radio-chemotherapy. Depending on the amount of apparently normal white matter measured around the tumor in the surgical specimen, the extent of surgery was classified into: "border resection" (BR, resection margins at the level of tumor border) or "extended resection" (ER, resection margins 1-2 cm far from tumor border). 88 patients had no residual tumor at post-operative MRI. Among these, 60 patients had a local recurrence (LR) - within 2 cm from the primary tumor's margins, 15 patients had a distant recurrence (DR), 13 patients had no recurrence. Survival curves were obtained through the Kaplan-Meier method. Dichotomous data were compared with the chi-square test.

RESULTS

Patients who underwent ER presented a LR in 67% of cases. Patients who underwent BR presented a LR in 87.5% of cases (p=0.03). Survival for 60 patients with LR was 16 months vs 35 months for 15 patients with DR (p=0.06). PFS for patients with LR was 9 months vs 21 months for patients with DR (p=0.05).

CONCLUSIONS

If tumor grows far from eloquent areas, ER may increase the probability to obtain a gross total resection, a greater number of patients with DR and, therefore, a longer survival.

Decompressive craniectomy for traumatic brain injury: patient age and outcome

The overall degree by which different patients may benefit from decompressive craniectomy (DC) remains controversial. In particular, the prognostic value of age has been investigated by very few studies. Many authors state there is no significant benefit in performing a DC in severe head injury after a certain age limit, with most placing the limit at 30-50 years of age. Between 1994 and 2004, 55 patients underwent DC at our institution. Advanced age did not constitute a contraindication to surgery for both ethical and cultural reasons. Thus, the data obtained were not biased by a selection of patients based on age. We analyzed potential predictors of outcome after DC, including sex, age, Glasgow Coma Scale (GCS), and presence of mass lesion. Chi-square test was used to compare categorical variables. The independent contribution of predictive factors to outcome was studied using logistic regression analysis. Initial GCS score was found to be an independent predictor of outcome (p = 0.001). No difference in the outcome was observed between patients with GCS 6-8 and GCS 9-15. These two groups have a better prognosis than patients with GCS 3-5. Logistic regression analysis showed age as an independent predictive factor to outcome (p = 0.005). A difference in outcome exists among patients over 65 and patients aged <or=65, while groups aged <40 and 40-65 showed no difference in outcome. Based on these findings, we believe that the age limit for performing DC should be revised.

Safety and efficacy of Gliadel wafers for newly diagnosed and recurrent glioblastoma

BACKGROUND

Combining Gliadel wafers and radiochemotherapy with TMZ may carry the risk of increased adverse events (AE). We analyzed the efficacy and safety in patients with glioblastoma who underwent multimodal treatment with implantation of Gliadel wafers.

METHODS

One hundred sixty-five consecutive patients with newly diagnosed (77 patients) or recurrent (88 patients) glioblastoma were studied. Forty-seven patients underwent surgery + Gliadel. The impact of age (≥65 vs. <65), resection extent (gross total vs. partial), use of Gliadel and adjuvant treatment (TMZ vs. other schemes/no adjuvant therapy) on overall survival (OS, for patients with newly diagnosed glioblastoma) and on recurrence-survival (for patients with recurrent glioblastoma) was analyzed with Cox regression. The impact of age, history (newly diagnosed vs. recurrent glioblastoma), number of Gliadel wafers implanted (0 vs. <8 vs. 8), resection extent (gross-total vs. partial) and adjuvant treatment (TMZ vs. other schemes/no adjuvant therapy) on the occurrence of AE and on the occurrence of implantation site-related AE (ISAE) was analyzed with the logistic regression model. Significance was set at p < 0.05.

RESULTS

Multivariate analysis showed the only factor associated with longer survival, both for newly diagnosed and for recurrent GBM, was resection extent. Both patients with a higher number of wafers implanted and patients with recurrent tumors were significantly at risk for AE and ISAE. Patients with eight Gliadel wafers implanted had a 3-fold increased risk of AE and a 5.6-fold increased risk of ISAE, and patients with recurrent tumor had a 2.8-fold increased risk of AE and a 9.3-fold increased risk of ISAE.

CONCLUSIONS

Adding Gliadel to standard treatment did not significantly improve the outcome. The toxicity after Gliadel use was significantly higher, both for patients with newly diagnosed and patients with recurrent glioblastoma.

Brain tumors in eloquent areas: A European multicenter survey of intraoperative mapping techniques, intraoperative seizures occurrence, and antiepileptic drug prophylaxis

Intraoperative mapping and monitoring techniques for eloquent area tumors are routinely used world wide. Very few data are available regarding mapping and monitoring methods and preferences, intraoperative seizures occurrence and perioperative antiepileptic drug management. A questionnaire was sent to 20 European centers with experience in intraoperative mapping or neurophysiological monitoring for the treatment of eloquent area tumors. Fifteen centers returned the completed questionnaires. Data was available on 2098 patients. 863 patients (41.1%) were operated on through awake surgery and intraoperative mapping, while 1235 patients (58.8%) received asleep surgery and intraoperative electrophysiological monitoring or mapping. There was great heterogeneity between centers with some totally AW oriented (up to 100%) and other almost totally ASL oriented (up to 92%) (31% SD). For awake surgery, 79.9% centers preferred an asleep-awake-asleep anesthesia protocol. Only 53.3% of the centers used ECoG or transcutaneous EEG. The incidence of intraoperative seizures varied significantly between centers, ranging from 2.5% to 54% (p < 0.001). It there appears to be a statistically significant link between the mastery of mapping technique and the risk of intraoperative seizures. Moreover, history of preoperative seizures can significantly increase the risk of intraoperative seizures (p < 0.001). Intraoperative seizures occurrence was similar in patients with or without perioperative drugs (12% vs. 12%, p = 0.2). This is the first European survey to assess intraoperative functional mapping and monitoring protocols and the management of peri- and intraoperative seizures. This data can help identify specific aspects that need to be investigated in prospective and controlled studies.

Primary cerebral lymphomatoid granulomatosis: report of four cases and literature review

BACKGROUND

Lymphomatoid granulomatosis (LYG) is an angiocentric and angiodestructive lymphoreticular proliferation, which usually involves the lungs, but may also involve the central nervous system (CNS). Unique involvement of the CNS has been reported rarely. We report our experience with LYG confined to the brain and review the pertinent literature.

PATIENTS AND METHODS

From January 1995 to September 2007, we identified patients with isolated brain LYG through a search of the histopathology database of the Catholic University of Rome; medical and radiological data were analyzed. Immunophenotype, in situ hybridization analysis of EBV-encoded small RNAs (EBER ISH) and immunoglobulin rearrangement studies were performed on the pathological specimens.

RESULTS

Four patients with brain-LYG (male/female 1:1, mean age 44 years) underwent surgery in the study period. Subsequent therapy was tailored according to LYG grading. At the latest follow-up (range from 18 to 221 months), patient conditions had improved in all cases. EBER ISH was negative in all cases. Study of the IgH chain gene documented a monoclonal pattern in two cases.

CONCLUSIONS

CNS-LYG is a rare disease that should be considered in the differential diagnosis of both diffuse and space-occupying cerebral lesions. Primary cerebral LYG seems not to be associated with EBV and appears to have a better prognosis than systemic LYG with CNS localization, which is frequently EBV positive.

Gene expression profile of glioblastoma peritumoral tissue: an ex vivo study

The gene expression pattern of glioblastoma (GBM) is well documented but the expression profile of brain adjacent to tumor is not yet analysed. This may help to understand the oncogenic pathway of GBM development. We have established the genome-wide expression profiles of samples isolated from GBM tumor mass, white matter adjacent to tumor (apparently free of tumor cells), and white matter controls by using the Affymetrix HG-U133 arrays. Array-CGH (aCGH) was also performed to detect genomic alterations. Among genes dysregulated in peritumoral white matter, 15 were over-expressed, while 42 were down-regulated when compared to white matter controls. A similar expression profile was detected in GBM cells. Growth, proliferation and cell motility/adhesion-associated genes were up-regulated while genes involved in neurogenesis were down-regulated. Furthermore, several tumor suppressor genes along with the KLRC1 (a member of natural killer receptor) were also down-regulated in the peritumoral brain tissue. Several mosaic genomic lesions were detected by aCGH, mostly in tumor samples and several GBM-associated mosaic genomic lesions were also present in the peritumoral brain tissue, with a similar mosaicism pattern. Our data could be explained by a dilution of genes expressed from tumor cells infiltrating the peritumour tissue. Alternatively, these findings could be substained by a relevant amount of “apparently normal” cells presenting a gene profile compatible with a precancerous state or even “quiescent” cancer cells. Otherwise, the recurrent tumor may arise from both infiltrating tumor cells and from an interaction and recruitment of apparently normal cells in the peritumor tissue by infiltrating tumor cells.

Selection of patients with idiopathic normal-pressure hydrocephalus for shunt placement: a single-institution experience

OBJECT

The ability to predict outcome after shunt placement in patients with idiopathic normal-pressure hydrocephalus (NPH) represents a challenge. To date, no single diagnostic tool or combination of tools has proved capable of reliably predicting whether the condition of a patient with suspected NPH will improve after a shunting procedure. In this paper, the authors report their experience with 120 patients with the goal of identifying CSF hydrodynamics criteria capable of selecting patients with idiopathic NPH. Specifically, they focused on the comparison between CSF-outflow resistance (R-out) and intracranial elastance (IE).

METHODS

Between January 1977 and December 2005, 120 patients in whom idiopathic NPH had been diagnosed (on the basis of clinical findings and imaging) underwent CSF hydrodynamics evaluation based on an intraventricular infusion test. Ninety-six patients underwent CSF shunt placement: 32 between 1977 and 1989 (Group I) on the basis of purely clinical and radiological criteria; 44 between 1990 and 2002 (Group II) on the basis of the same criteria as Group I and because they had an IE slope > 0.25; and 20 between 2003 and 2005 (Group III) on the basis of the same criteria as Group II but with an IE slope > or = 0.30. Outcomes were evaluated by means of both Stein-Langfitt and Larsson scores. Patients' conditions were considered improved when there was a stable decrease (at 6- and 12-month follow-up) of at least 1 point in the Stein-Langfitt score and 2 points in the Larsson score.

RESULTS

Group I: while no statistically significant difference in mean R-out value between improved and unimproved cases was observed, a clear-cut IE slope value of 0.25 differentiated very sharply between unimproved and improved cases. Group II: R-out values in the 2 unimproved cases were 20 and 47 mm Hg/ml/min, respectively. The mean IE slope in the improved cases was 0.56 (range 0.30-1.4), while the IE slopes in the 2 unimproved cases were 0.26 and 0.27. Group III: the mean IE slope was 0.51 (range 0.31-0.7). The conditions of all patients improved after shunting. A significant reduction of the Evans ratio was observed in 34 (40.5%) of the 84 improved cases and in none of the unimproved cases.

CONCLUSIONS

Our strategy based on the analysis of CSF pulse pressure parameters seems to have a great accuracy in predicting surgical outcome in clinical practice.

Postoperative infection may influence survival in patients with glioblastoma: simply a myth?

BACKGROUND

It is a prevalent myth that a postoperative infection may actually confer a survival advantage in patients with malignant glioma. This contention is based largely on anecdotal reports. Recently, a single-center study showed there was no survival advantage in those patients who had glioblastoma with postoperative infection.

OBJECTIVE

To examine the impact of postoperative infections on outcome in patients with glioblastoma treated at our center.

METHODS

This study included 197 patients with newly diagnosed primary glioblastoma treated from January 2001 to January 2008. Of the 197 patients, 10 (5.08%) had postoperative bacterial infection. The Kaplan-Meier method, log-rank test, and Breslow test were used in the univariate approach; Cox regression was used in the multivariable approach.

RESULTS

The median survival was 16 months (95% confidence interval [CI], 14-18 mo). The infection group had a significant advantage in the median survival: 30 months (95% CI, 21-39) vs 15 months (95% CI, 13-17) for patients without postoperative infection. This advantage was also confirmed by Cox regression; in fact, patients not developing a postoperative infection showed an adjusted hazard ratio for death of 2.3 (95% CI, 1-5.3).

CONCLUSION

The association between infection and prolonged survival is not definitive; we acknowledge the considerable difficulties in undertaking this type of study in a retrospective manner. Our results can instead stimulate further multicentric studies (to increase the number of patients) or experimental studies using genetically modified bacteria for treatment of glioblastoma.

The impact of repeated surgery and adjuvant therapy on survival for patients with recurrent glioblastoma

OBJECTIVE

Treatment of glioblastoma recurrence can have a palliative aim, after considering risks and potential benefits. The aim of this study is to verify the impact of surgery and of palliative adjuvant treatments on survival after recurrence.

METHODS

From January 2002 to June 2008, we treated 76 consecutive patients with recurrent glioblastoma. Treatment was: 1-surgery alone--17 patients; 2-adjuvant-therapy alone--24 patients; 3-surgery and adjuvant therapy--16 patients; no treatment--19 patients. The impact on median overall-survival (OS-time between recurrence and death/last follow-up) of age, Karnofsky performance scale (KPS), resection extent and adjuvant treatment scheme (Temozolomide alone vs low-dose fractionated radiotherapy vs others) was determined. Survival curves were obtained through the Kaplan-Meier method. Cox proportional-hazards was used for multivariate analyses. Significance was set at p<0.05.

RESULTS

Median OS was 7 months. At univariate analysis, patients with a KPS≥70 had a longer OS (9 months vs 5 months--p<0.0001). OS was 6 months for patients treated with surgery alone, 5 months for patients that received no treatment, 8 months for patients treated with chemotherapy alone, 14 months for patients treated with surgery and adjuvant therapy--p=0.01. Patients with a KPS<70 were significantly at risk for death - HR 2.8 - p=0.001. Subgroup analysis showed no significant differences between patients receiving gross total or partial tumor resection and among patients receiving different adjuvant therapy schemes. Major surgical morbidity at tumor recurrence occurred in 16 out of 33 patients (48%).

CONCLUSION

It is fundamental, before deciding to operate patients for recurrence, to carefully consider the impact of surgical morbidity on outcome.

Intracranial pressure wave morphological classification: automated analysis and clinical validation

BACKGROUND

Recently, different software has been developed to automatically analyze multiple intracranial pressure (ICP) parameters, but the suggested methods are frequently complex and have no clinical correlation. The objective of this study was to assess the clinical value of a new morphological classification of the cerebrospinal fluid pulse pressure waveform (CSFPPW), comparing it to the elastance index (EI) and CSF-outflow resistance (Rout), and to test the efficacy of an automatic ICP analysis.

METHODS

An artificial neural network (ANN) was trained to classify 60 CSFPPWs in four different classes, according to their morphology, and its efficacy was compared to an expert examiner's classification. The morphology of CSFPPW, recorded in 60 patients at baseline, was compared to EI and Rout calculated at the end of an intraventricular infusion test to validate the utility of the proposed classification in patients' clinical evaluation.

RESULTS

The overall concordance in CSFPPW classification between the expert examiner and the ANN was 88.3 %. An elevation of EI was statistically related to morphological class' progression. All patients showing pathological baseline CSFPPW (class IV) revealed an alteration of CSF hydrodynamics at the end of their infusion test.

CONCLUSIONS

The proposed morphological classification estimates the global ICP wave and its ability to reflect or predict an alteration in CSF hydrodynamics. An ANN can be trained to efficiently recognize four different CSF wave morphologies. This classification seems helpful and accurate for diagnostic use.

The eagle jugular syndrome

BACKGROUND

The elongation of the styloid process is historically associated with two variants of the Eagle syndrome. The classic one, mainly characterized by pain and dysphagia, and the carotid variant characterized by pain and sometimes by cerebral ischemia. We observed a further variant characterized by a styloid elongation coursing adjacent to the transverse process of C1, causing significant compression of the internal jugular vein.

METHODS

We reviewed all the cases of Eagle syndrome, including the jugular variant, admitted in our Hospital in the last six years. We compared symptomatology, associated comorbidities and imaging. Data were statistically analyzed.

RESULTS

Overall 23 patients were admitted to the Hospital for symptomatic elongation of the styloid process, 11 male and 12 females. The jugular variant of the Eagle syndrome is clinically delineated by significant differences, as compared to the classic variant and carotid variants. Headache was the more prominent symptom (p < .009) as well as a documented peri-mesencephalic hemorrhage was the more significant comorbidity (p < .0003). The group classic-carotid variant was characterized by ipsilateral pain respect to the jugular variant (p < .0003). CT angiography with venous phase extended to the neck veins and imaging reconstruction is highly recommended as imaging technique, complemented by color-Doppler ultrasound.

CONCLUSIONS

The elongation of the styloid process may have different paths which creates compression on the surrounding anatomical structures. There may be a possible association of jugular impingement by an elongated styloid process with symptoms.

TRIAL REGISTRATION

Protocol n°45-2013.

Decompressive craniectomy for elderly patients with traumatic brain injury: it's probably not worth the while

Decompressive craniectomy (DC) has been regarded as an ultima ratio measure in the treatment of refractory intracranial hypertension after brain injury. Most discussion about its benefits is based on studies performed in patients who are <65 years of age. The aim of this study was to identify patients aged ≥66 years who underwent DC after traumatic brain injury (TBI), in order to assess patient outcome and to correlate the values of potential predictors of survival on prognosis. From January 2002 to December 2009, 44 patients aged ≥66 underwent DC (follow-up, 12-102 months). Potential predictors of outcome were analyzed, including age, post-resuscitation Glasgow Coma Scale (GCS) score, presence of mass lesion, Simplified Acute Physiology Score (SAPS) II, Injury Severity Score (ISS), and timing of surgical decompression. Mortality was 48% at discharge from the intensive care unit (ICU), 57% at hospital discharge, and 77% at 1-year follow-up and at last follow-up. A bad outcome Glasgow Outcome Scale Dead-Vegetative State-Severely Disabled (GOS D-VS-SD) was observed in 36/44 patients both at hospital discharge and at 1-year follow-up. Mean SAPS II was 45.2 for patients who survived and 57.3 for patients who had died (p=0.0022). Patients who survived had a higher mean post-resuscitation GCS score (p=0.02). Logistical regression analysis indicated post-resuscitation GCS score as the only independent predictive factor for outcome. None of the 22 patients with a post-resuscitation GCS score of 3-5 had a good outcome, 2/10 (20%) patients with a post-resuscitation GCS score of 6-8 and 6/12 patients (50%) with a post-resuscitation GCS score ≥9 had a good outcome.

The transcriptome and miRNome profiling of glioblastoma tissues and peritumoral regions highlights molecular pathways shared by tumors and surrounding areas and reveals differences between short-term and long-term survivors

Glioblastoma multiforme (GBM) is the most common and deadliest primary brain tumor, driving patients to death within 15 months after diagnosis (short term survivors, ST), with the exception of a small fraction of patients (long term survivors, LT) surviving longer than 36 months. Here we present deep sequencing data showing that peritumoral (P) areas differ from healthy white matter, but share with their respective frankly tumoral (C) samples, a number of mRNAs and microRNAs representative of extracellular matrix remodeling, TGFβ and signaling, of the involvement of cell types different from tumor cells but contributing to tumor growth, such as microglia or reactive astrocytes. Moreover, we provide evidence about RNAs differentially expressed in ST vs LT samples, suggesting the contribution of TGF-β signaling in this distinction too. We also show that the edited form of miR-376c-3p is reduced in C vs P samples and in ST tumors compared to LT ones. As a whole, our study provides new insights into the still puzzling distinction between ST and LT tumors, and sheds new light onto that "grey" zone represented by the area surrounding the tumor, which we show to be characterized by the expression of several molecules shared with the proper tumor mass.

MicroRNA-221 silencing attenuates the degenerated phenotype of intervertebral disc cells

The aim of this study was to investigate the role of an antichondrogenic factor, MIR221 (miR-221), in intervertebral disc degeneration (IDD), and provide basic information for the development of a therapeutic strategy for the disc repair based on specific nucleic acid based drugs, such as miR-221 silencing. We established a relatively quick protocol to minimize artifacts from extended in vitro culture, without selecting the different types of cells from intervertebral disc (IVD) or completely disrupting extracellular matrix (ECM), but by using the whole cell population with a part of resident ECM. During the de-differentiation process miR-221 expression significantly increased. We demonstrated the effectiveness of miR-221 silencing in driving the cells towards chondrogenic lineage. AntagomiR-221 treated cells showed in fact a significant increase of expression of typical chondrogenic markers including COL2A1, ACAN and SOX9, whose loss is associated with IDD. Moreover, antagomiR-221 treatment restored FOXO3 expression and increased TRPS1 expression levels attenuating the severity grade of degeneration, and demonstrating in a context of tissue degeneration and inflammation not investigated before, that FOXO3 is target of miR-221. Data of present study are promising in the definition of new molecules useful as potential intradiscal injectable biological agents.

Cranial and spinal subdural empyema

Subdural empyema represents a loculated suppuration between the dura and the arachnoid. It has been described either intracranially or in the spinal canal, the latter localization being quite rare. It is a rare but serious illness with a declining mortality rate but rather frequent neurological sequelae. Morbidity and mortality in intracranial and spinal subdural empyema directly relate to the delay in diagnosis and therapy. The epidemiology, etiology, pathophysiology and symptoms of spinal subdural empyema and cranial subdural empyema are somewhat different, but brain and spinal subdural empyema are not always two different entities. An adequate treatment strategy should be selected on a case-by-case basis, especially for patients with a massive CNS involvement, where management represents a challenge.

Learning curve of endoscopic pituitary surgery: Experience of a neurosurgery/ENT collaboration

For neurosurgeons, who are accustomed to the binocular microscope, there is a new learning curve that must be overcome for monocular endoscopic pituitary surgery. Different studies describe a learning curve between 15 and 200 procedures, after which both operative time and complications stabilize. In this retrospective study, we evaluate the endoscopic learning curve of our group, already trained in microsurgical transsphenoidal surgery, with the assistance of ear, nose, and throat (ENT) surgeons. From 2010 to 2015, a total of 95 patients with pituitary adenomas were treated with a purely endoscopic approach. The latest 48 patients treated with the endoscope (L group) were compared with the 47 initial patients treated with the endoscope (E group) and with 43 patients treated with the microscope (M group), in terms of surgical time, complications, and tumor removal rate. The complication rate was similar in all the groups, as was the rate of total adenoma resection. Mean surgical time was shorter in the L group than in the E group (115±36min vs. 157±46 min, p<0.001); the average operative time was also shorter in the L group than in the M group (135±43min). The estimated reduction in duration of surgery per 10 patients was 9min (p<0.001). Over time, blood transfusions discrepantly increased from the E group to the L group (11% vs. 31%). Because of the pivotal role of ENT in the transnasal stage of 50 endoscopic procedures, we obtained an operative time comparable to that of microscopic procedures, with similar complication rate and gross total resections. Neurosurgical-ENT combined follow-up proved to be a fundamental protection from late complications.

Progenitor/Stem Cell Markers in Brain Adjacent to Glioblastoma: GD3 Ganglioside and NG2 Proteoglycan Expression

Characterization of tissue surrounding glioblastoma (GBM) is a focus for translational research because tumor recurrence invariably occurs in this area. We investigated the expression of the progenitor/stem cell markers GD3 ganglioside and NG2 proteoglycan in GBM, peritumor tissue (brain adjacent to tumor, BAT) and cancer stem-like cells (CSCs) isolated from GBM (GCSCs) and BAT (PCSCs). GD3 and NG2 immunohistochemistry was performed in paired GBM and BAT specimens from 40 patients. Double-immunofluorescence was carried out to characterize NG2-positive cells of vessel walls. GD3 and NG2 expression was investigated in GCSCs and PCSCs whose tumorigenicity was also evaluated in Scid/bg mice. GD3 and NG2 expression was higher in tumor tissue than in BAT. NG2 decreased as the distance from tumor margin increased, regardless of the tumor cell presence, whereas GD3 correlated with neoplastic infiltration. In BAT, NG2 was coexpressed with a-smooth muscle actin (a-SMA) in pericytes and with nestin in the endothelium. Higher levels of NG2 mRNA and protein were found in GCSCs while GD3 synthase was expressed at similar levels in the 2 CSC populations. PCSCs had lower tumorigenicity than GCSCs. These data suggest the possible involvement of GD3 and NG2 in pre/pro-tumorigenic events occurring in the complex microenvironment of the tissue surrounding GBM.

Decompressive craniectomy for the treatment of traumatic brain injury: does an age limit exist?

OBJECT

It is generally believed that the outcome of traumatic brain injury is not improved by decompressive craniectomy in patients older than 30-50 years. A literature search was performed to assess the level of evidence with respect to the effect of age on outcome in these cases.

METHODS

References were identified by PubMed searches of journal articles published between 1995 and December 2008. The inclusion criteria were as follows: 1) clinical series including adults; and 2) focus on age as a prognostic factor. Technical notes and laboratory investigations were excluded.

RESULTS

Fourteen English-language articles were finally selected. In 5 of the 14 studies, the authors performed no statistical analysis. In 6 studies they concluded that age was not significantly related to outcome (with 1 of these studies showing a correlation between age and outcome only after 65 years). Three studies showed a correlation between age and outcome.

CONCLUSIONS

With respect to age and effectiveness of decompressive craniectomy, there are no robust data to establish any degree of core evidence and the referred age thresholds are arbitrary.