Polycystin‐1 regulates cell proliferation and migration through AKT/mTORC2 pathway in a human craniosynostosis cell model

Craniosynostosis is the premature fusion of skull sutures and has a severe pathological impact on childrens’ life. Mechanical forces are capable of triggering biological responses in bone cells and regulate osteoblastogenesis in cranial sutures, leading to premature closure. The mechanosensitive proteins polycystin‐1 (PC1) and polycystin‐2 (PC2) have been documented to play an important role in craniofacial proliferation and development. Herein, we investigated the contribution of PC1 to the pathogenesis of non‐syndromic craniosynostosis and the associated molecular mechanisms. Protein expression of PC1 and PC2 was detected in bone fragments derived from craniosynostosis patients via immunohistochemistry. To explore the modulatory role of PC1 in primary cranial suture cells, we further abrogated the function of PC1 extracellular mechanosensing domain using a specific anti‐PC1 IgPKD1 antibody. Effect of IgPKD1 treatment was evaluated with cell proliferation and migration assays. Activation of PI3K/AKT/mTOR pathway components was further detected via Western blot in primary cranial suture cells following IgPKD1 treatment. PC1 and PC2 are expressed in human tissues of craniosynostosis. PC1 functional inhibition resulted in elevated proliferation and migration of primary cranial suture cells. PC1 inhibition also induced activation of AKT, exhibiting elevated phospho (p)‐AKT (Ser473) levels, but not 4EBP1 or p70S6K activation. Our findings indicate that PC1 may act as a mechanosensing molecule in cranial sutures by modulating osteoblastic cell proliferation and migration through the PC1/AKT/mTORC2 cascade with a potential impact on the development of non‐syndromic craniosynostosis.

Histone Mark Profiling in Pediatric Astrocytomas Reveals Prognostic Significance of H3K9 Trimethylation and Histone Methyltransferase SUV39H1

Alterations in global histone methylation regulate gene expression and participate in cancer onset and progression. The profile of histone methylation marks in pediatric astrocytomas is currently understudied with limited data on their distribution among grades. The global expression patterns of repressive histone marks H3K9me3, H3K27me3, and H4K20me3 and active H3K4me3 and H3K36me3 along with their writers SUV39H1, SETDB1, EZH2, MLL2, and SETD2 were investigated in 46 pediatric astrocytomas and normal brain tissues. Associations between histone marks and modifying enzymes with clinicopathological characteristics and disease-specific survival were studied along with their functional impact in proliferation and migration of pediatric astrocytoma cell lines using selective inhibitors in vitro. Upregulation of histone methyltransferase gene expression and deregulation of histone code were detected in astrocytomas compared to normal brain tissues, with higher levels of SUV39H1, SETDB1, and SETD2 as well as H4K20me3 and H3K4me3 histone marks. Pilocytic astrocytomas exhibited lower MLL2 levels compared to diffusely infiltrating tumors indicating a differential pattern of epigenetic regulator expression between the two types of astrocytic neoplasms. Moreover, higher H3K9me3, H3K36me3, and SETDB1 expression was detected in grade IIΙ/IV compared to grade II astrocytomas. In univariate analysis, elevated H3K9me3 and MLL2 and diminished SUV39H1 expression adversely affected survival. Upon multivariate survival analysis, only SUV39H1 expression was revealed as an independent prognostic factor of adverse significance. Treatment of pediatric astrocytoma cell lines with SUV39H1 inhibitor reduced proliferation and cell migration. Our data implicate H3K9me3 and SUV39H1 in the pathobiology of pediatric astrocytomas, with SUV39H1 yielding prognostic information independent of other clinicopathologic variables.

Polycystin-1 modulates RUNX2 activation and osteocalcin gene expression via ERK signalling in a human craniosynostosis cell model

Craniosynostosis refers to the premature fusion of one or more cranial sutures leading to skull shape deformities and brain growth restriction. Among the many factors that contribute to abnormal suture fusion, mechanical forces seem to play a major role. Nevertheless, the underlying mechanobiology-related mechanisms of craniosynostosis still remain unknown. Understanding how aberrant mechanosensation and mechanotransduction drive premature suture fusion will offer important insights into the pathophysiology of craniosynostosis and result in the development of new therapies, which can be used to intervene at an early stage and prevent premature suture fusion. Herein, we provide evidence for the first time on the role of polycystin-1 (PC1), a key protein in cellular mechanosensitivity, in craniosynostosis, using primary cranial suture cells isolated from patients with trigonocephaly and dolichocephaly, two common types of craniosynostosis. Initially, we showed that PC1 is expressed at the mRNA and protein level in both trigonocephaly and dolichocephaly cranial suture cells. Followingly, by utilizing an antibody against the mechanosensing extracellular N-terminal domain of PC1, we demonstrated that PC1 regulates runt-related transcription factor 2 (RUNX2) activation and osteocalcin gene expression via extracellular signal-regulated kinase (ERK) signalling in our human craniosynostosis cell model. Altogether, our study reveals a novel mechanotransduction signalling axis, PC1-ERK-RUNX2, which affects osteoblastic differentiation in cranial suture cells from trigonocephaly and dolichocephaly patients.

Antiepileptics for Post-Traumatic Seizure Prophylaxis after Traumatic Brain Injury

Traumatic brain injury (TBI) is an important public health concern plagued by high rates of mortality and significant long-term disability in many survivors. Post-traumatic seizures (PTS) are not uncommon following TBI, both in the early (within 7 days post-injury) and late (after 7 days post-injury) period. Due to the potential of PTS to exacerbate secondary injury following TBI and the possibility of developing post-traumatic epilepsy (PTE), the medical community has explored preventative treatment strategies. Prophylactic antiepileptic drug (AED) administration has been proposed as a measure to reduce the incidence of PTS and the ultimate development of PTE in TBI patients. In this topical review, we discuss the pathophysiologic mechanisms of early and late PTS and the development of PTE following TBI, the pharmacodynamic and pharmacokinetic properties of AEDs commonly used to prevent post-traumatic seizures, and summarize the available clinical evidence for employing AEDs for seizure prophylaxis after TBI.

Fibrous dysplasia of occipital and temporal bone. A case report

Fibrous dysplasia is a rare non-malignant condition where fibrous tissue replaces the normal bone architecture. Involvement of temporal and occipital bones is exceptionally rare and is associated with unique complications. A 10-year-old boy presented with right retroauricular enlargement and pain. Imaging studies and biopsy revealed fibrous dysplasia of the temporal and occipital bones. There was no hearing loss or sequelae arising from posterior fossa compression. The patient was discharged with follow-up instructions. Only 10 cases of occipital bone fibrous dysplasia have been reported in the medical literature. Occipital bone fibrous dysplasia can be complicated with Chiari malformation and syringomyelia while temporal bone involvement is associated with hearing loss. These potential developments require close follow-up that includes detailed neurologic examination, imaging and audiology.

Giant intracranial congenital hemangiopericytoma/solitary fibrous tumor: A case report and literature review

BACKGROUND

Hemangiopericytoma and solitary fibrous tumor (HPC/SFT) are considered to be one category according to the WHO 2016 classification of central nervous system tumors. HPC/SFT are subdivided into infantile (congenital) and adult type. Both are extremely rare entities, with little knowledge about etiology, prognosis, and optimal therapeutic strategy.

CASE DESCRIPTION

A 10-day-old girl was referred to our neurosurgical department due to hypotonia, palsy of the right oculomotor nerve, and prominent frontal fontanel. Imaging studies revealed a large occupying mass in the right middle cerebral fossa and the suprasellar cisterns. Only a subtotal resection of the tumor was possible, and postoperatively, she underwent chemotherapy (CHx). After a 3-year follow-up, the girl has minimum neurologic signs and receives no medications, and she can walk when she is supported.

CONCLUSION

Congenital HPC/SFT is considered to have a benign behavior with a good prognosis. Treatment with gross total resection, when it is feasible, is the key to a good prognosis and low rates of recurrence. However, there is no consensus on the therapeutic strategy of a HPC/SFT, which is difficult to be completely resected. Literature lacks a therapeutic algorithm for these tumors, and thus, more clinical studies are needed to reach a consensus.

Pediatric infratentorial subdural empyema: A case report

Background:

Infratentorial subdural empyemas in children are extremely rare and potentially lethal intracranial infections. Delay in diagnosis and therapy is associated with increased morbidity and mortality.

Case Description:

A 4-year-old boy presented with cerebellar signs following a failed treatment of otitis media. Imaging studies revealed a subdural empyema and left transverse and sigmoid sinus thrombosis. The empyema was evacuated operatively and antibiotic treatment was initiated and administered for 6 weeks. The patient recovered fully and was discharged 4 weeks following the evacuation of the empyema.

Conclusion:

While prompt identification and treatment of subdural infratentorial empyemas are crucial for favorable outcomes, their diagnosis in children might be initially missed. This is, in part because they are so rare and in part, because imaging artifacts arising from the complex posterior fossa anatomy may obscure their presence in the computer tomography (CT) scan. Therefore, high level of suspicion is necessary, given the appropriate history and clinical presentation. In children, this is a recent history of protracted otitis media and central nervous system symptomatology—cerebellar or other.

Chromatin remodeling defects in pediatric brain tumors

Brain tumors are regarded as the most prevalent solid neoplasms in children and the principal reason of death in this population. Even though surgical resection, radiotherapy and chemotherapy have improved outcome, a significant number of patients die in 6-12 months after diagnosis while those who survive, frequently experience side effects and relapses. Several studies suggest that many types of cancer including pediatric brain tumors are characterized by alterations in epigenetic profiles with deregulated chromatin remodeling and posttranslational covalent histone modifications playing a prominent role. Moreover, interplay of genetic and epigenetic changes has been associated to tumor growth and invasion as well as to modulation of patient's response to current treatment. Therefore, detection of tumor-specific histone changes and elucidation of the underlying gene defects will allow successful tailoring of personalized treatment. The goal of this review is to provide an update of genetic and epigenetic alterations that characterize pediatric brain tumors focusing on histone modifications, aiming at directing future molecular and epigenetic therapeutic targeting.

Paediatric gliomas: diagnosis, molecular biology and management

Paediatric gliomas represent the most common brain tumour in children. Early diagnosis and treatment greatly improve survival. Histological grade is the most significant classification system affecting treatment planning and prognosis. Paediatric gliomas depend on pathways and genes responsible for mitotic activity and cell proliferation as well as angiogenesis (MAPK, VEGF, EFGR pathways). Symptoms such as focal neurologic deficit or seizures can facilitate diagnosis, but they are not always present and therefore diagnosis is occasionally delayed. Imaging has adequate diagnostic accuracy (surpassing 90%), and novel imaging techniques such as MR spectroscopy and PET increase only slightly this percentage. Low grade gliomas (LGG) can be approached conservatively but most authors suggest surgical excision. High grade gliomas (HGG) are always operated with exception of specific contradictions including butterfly or extensive dominant hemisphere gliomas. Surgical excision is universally followed by radiotherapy and chemotherapy, which slightly increase survival. Inoperable cases can be managed with or without radiosurgery depending on location and size, with adjunctive use of radiotherapy and chemotherapy. Surgical excision must be aggressive and gross total resection (GTR) should be attempted, if possible, since it can triple survival. Radiosurgery is effective on smaller tumours of <2 cm2. Surgical excision is always the treatment of choice, but glioma recurrences, and residual tumours in non-critical locations are candidates for radiosurgery especially if tumour volume is low. Management of recurrences includes surgery, radiosurgery and chemoradiotherapy and it should be individualized according to location and size. In combination with molecular targeted therapeutic schemes, glioma management will be immensely improved in the next years.

Colchicine in Neurosurgery

BACKGROUND

Colchicine is an ancient drug. Many uses have been reported in medical books and reports through the centuries. Currently the understanding of its mechanism of action has opened new horizons to its use.

OBJECTIVE

This article aims to discuss the use of colchicine in various neurosurgical conditions.

METHODS

A pubmed database and clinical trials search was performed, using the key words "colchicine", "Neurosurgery", "low back pain", "stroke" and glioma".

RESULTS

Various reports were found contemplating the use of colchicine in chronic low-back pain. The effect of the drug on neutrophil chemotaxis and its role as an anti-inflammatory agent has been the main argument upon which such use of colchicine has been structured. These characteristics have been the key to initiate colchicine as a preventive agent in vascular conditions. Furthermore, as colchicine is an antimitotic drug, it is currently being studied as a potential anti-glioma agent. However, the narrow therapeutic index of the drug is a discouraging factor in clinical application of colchicine in these entities. Therefore, colchicine derivatives that can exert the same effectiveness in lower doses are being studied, forming a new direction in colchicine use.

CONCLUSION

Colchicine is a drug that over the years has shown promising results in certain neurosurgical entities. Its derivatives or potential colchicine-like agents might have a more significant place in neurosurgical practice.

Aplasia cutis congenita: Two case reports and discussion of the literature

Background:

Aplasia cutis congenita (ACC) is a part of a heterogeneous group of conditions characterized by the congenital absence of epidermis, dermis, and in some cases, subcutaneous tissues or bone usually involving the scalp vertex. There is an estimated incidence of 3 in 10,000 births resulting in a total number of 500 reported cases to date. The lesions may occur on every body surface although localized scalp lesions form the most frequent pattern (70%). Complete aplasia involving bone defects occurs in approximately 20% of cases. ACC can occur as an isolated defect or can be associated with a number of other congenital anomalies such as limb anomalies or embryologic malformations. In patients with large scalp and skull defects, there is increased risk of infection and bleeding along with increased mortality and therefore prompt and effective management is advised.

Case Description:

We describe two cases of ACC, involving a 4 × 3 cm defect managed conservatively and a larger 10 × 5 cm defect managed surgically with the use of a temporo-occipital scalp flap. Both cases had an excellent outcome.

Conclusions:

Multiple treatment regimens exist for ACC, but there is no consensus on treatment strategies. Conservative treatment has been described and advocated, but many authors have emphasized the disadvantages of this treatment modality. Decision between conservative and surgical management must be individualized according to lesion size and location.

AED Strategy after Refractory Epilepsy Surgery

Post-epilepsy surgery antiepileptic drug discontinuation (AED) practices remain unclear and little evidence about the optimum timing exists. In the present study, we reviewed the types of surgery for epilepsy and their outcome. The current concepts for discontinuation of AED after surgery are presented and all contributing factors that should be taken into consideration are discussed.

The Use of Antiepileptic Drugs in Paediatric Neurosurgical Conditions

BACKGROUND

Epileptic seizures are a relatively common problem in pediatric neurosurgery that can have physical, mental and/or behavioral implications. Pediatric neurosurgery is involved in the treatment of secondary epilepsy, which is mainly associated with brain tumors, traumatic brain injury and intracranial vascular malformations.

OBJECTIVE

The aim of this article is to review the current literature for commonly used antiepileptic drugs in pediatric neurosurgery and offer an updated view on epilepsy treatment with antiepileptic drugs in the most commonly encountered neurosurgical entities in the pediatric population.

METHODS AND MATERIALS

Current literature has been reviewed for epilepsy, antiepileptic drugs and common neurosurgical conditions in children that cause seizures and/or epilepsy. Epidemiological features, epileptogenesis and treatment have been thoroughly examined.

CONCLUSION

The most common neurosurgical conditions that cause seizures and/or epilepsy in the pediatric population are brain tumors and traumatic brain injury. Newer antiepileptic drugs are powerful instruments in the management of epilepsy and they improve the quality of life of patients as well as decrease the epilepsy associated morbidity.

The Insertion of Electrodes in the Brain for Electrophysiological Recording or Chronic Stimulation Is Not Associated With Any Biochemically Detectable Neuronal Injury

OBJECTIVE

The aim of this study was to evaluate the degree of brain tissue injury that could be potentially induced by the introduction of a) microrecording electrodes, b) macrostimulation electrodes, or c) chronic stimulation electrodes. We aimed to evaluate whether the use of five simultaneous microrecording tracks is associated with any brain injury not detectable by conventional imaging such as CT or MRI.

MATERIALS AND METHODS

The study included 61 patients who underwent surgery for implantation of 121 DBS leads. In all cases, five simultaneous tracts were utilized for microelectrode recordings. All patients underwent measurements of serum S-100b at specific time points as follows: a) prior to the operation, and b) intraoperatively at specific stages of the procedure: 1) after opening the burr hole, 2) after the insertion of microrecording electrodes, 3) during macrostimulation, 4) at the end of the operation, and 5) on the first postoperative day.

RESULTS

The levels of serum S-100B protein remained within the normal range during the entire period of investigation in all patients with the exception of two cases. In both patients, the procedure was complicated by intraparenchymal hemorrhage visible in neuro-imaging. The first patient developed a small intraparenchymal hemorrhage, visible on the postoperative MRI, with no neurological deficit. The second patient experienced a focal epileptic seizure after the insertion of the right DBS chronic lead and the postoperative CT scan revealed a right frontal lobe hemorrhage.

CONCLUSION

These results strongly indicate that the insertion of either multiple recording electrodes or the implantation of chronic electrodes in DBS does not increase the risk of brain hemorrhage or of other intracranial complications, and furthermore it does not cause any biochemically detectable brain tissue damage.

Herpes simplex virus Type 1 encephalitis in an adolescent presenting with acute hydrocephalus

Herpes simplex virus Type 1 (HSV-1) is a human neurotropic virus causing encephalitis, corneal blindness or several peripheral nervous system disorders. Herpes Simplex encephalitis (HSE) is the most devastating clinical syndrome with severe morbidity and mortality. Hydrocephalus associated with viral meningoencephalitis is an extremely rare entity with only few documented cases, predominantly due to HSV-2 infection. HSV-1 infection of central nervous system present in the majority of the cases as encephalitis. We report a rare case of an 11-year-old child suffering from HSV-1 infection of central nervous system causing hydrocephalus without evidence of encephalitis.

Emerging role of linker histone variant H1x as a biomarker with prognostic value in astrocytic gliomas. A multivariate analysis including trimethylation of H3K9 and H4K20

Although epigenetic alterations play an essential role in gliomagenesis, the relevance of aberrant histone modifications and the respective enzymes has not been clarified. Experimental data implicates histone H3 lysine (K) methyltransferases SETDB1 and SUV39H1 into glioma pathobiology, whereas linker histone variant H1.0 and H4K20me3 reportedly affect prognosis. We investigated the expression of H3K9me3 and its methyltransferases along with H4K20me3 and H1x in 101 astrocytic tumors with regard to clinicopathological characteristics and survival. The effect of SUV39H1 inhibition by chaetocin on the proliferation, colony formation and migration of T98G cells was also examined. SETDB1 and cytoplasmic SUV39H1 levels increased from normal brain through low-grade to high-grade tumors, nuclear SUV39H1 correlating inversely with grade. H3K9me3 immunoreactivity was higher in normal brain showing no association with grade, whereas H1x and H4K20me3 expression was higher in grade 2 than in normal brain or high grades. These expression patterns of H1x, H4K20me3 and H3K9me3 were verified by Western immunoblotting. Chaetocin treatment significantly reduced proliferation, clonogenic potential and migratory ability of T98G cells. H1x was an independent favorable prognosticator in glioblastomas, this effect being validated in an independent set of 66 patients. Diminished nuclear SUV39H1 expression adversely affected survival in univariate analysis. In conclusion, H4K20me3 and H3K9 methyltransferases are differentially implicated in astroglial tumor progression. Deregulation of H1x emerges as a prognostic biomarker.

Sox11 expression in astrocytic gliomas: correlation with nestin/c-Met/IDH1-R132H expression phenotypes, p-Stat-3 and survival

Background:

Sox11 is a transcription factor expressed in foetal and neoplastic brain tissue, including gliomas. It has been shown to suppress the tumourigenicity of glioma stem cells in vivo, thereby being hypothesised to function as a tumour suppressor.

Methods:

We investigated the expression of Sox11 in 132 diffuse astrocytomas in relation to the regulator cell marker nestin, c-Met and IDH1-R132H, which have shown to be differentially expressed among the molecular subgroups of malignant gliomas, as well as to an inducer of astrocytic differentiation, that is, signal transducer and activator of transcription (p-STAT-3), clinicopathological features and survival.

Results:

Sox11 immunoreactivity was identified in all tumours irrespective of grade, but being correlated with p-STAT-3. Three out of seven cases showed partial Sox11 promoter methylation. In >50% of our cases neoplastic cells coexpressed Sox11 and nestin, a finding further confirmed in primary glioblastoma cell cultures. Furthermore, nestin, c-Met and IDH1-R132H expression differed among grade categories. Cluster analysis identified four groups of patients according to c-Met, nestin and IDH1-R132H expression. The c-Met/nestin high-expressor group displayed a higher Sox11 expression. Sox11 expression was an indicator of favourable prognosis in glioblastomas, which remained in multivariate analysis and validated in an independent set of 72 cases. The c-Met/nestin high-expressor group was marginally with shorter survival in univariate analysis.

Conclusions:

We highlight the importance of Sox11 expression as a favourable prognosticator in glioblastomas. c-Met/nestin/IDH1-R132H expression phenotypes recapitulate the molecular subgroups of malignant glioma.

Malignant neuroleptic syndrome following deep brain stimulation surgery: a case report

Background

The neuroleptic malignant syndrome is an uncommon but dangerous complication characterized by hyperthermia, autonomic dysfunction, altered mental state, hemodynamic dysregulation, elevated serum creatine kinase, and rigor. It is most often caused by an adverse reaction to anti-psychotic drugs or abrupt discontinuation of neuroleptic or anti-parkinsonian agents. To the best of our knowledge, it has never been reported following the common practice of discontinuation of anti-parkinsonian drugs during the pre-operative preparation for deep brain stimulation surgery for Parkinson's disease.

Case presentation

We present the first case of neuroleptic malignant syndrome associated with discontinuation of anti-parkinsonian medication prior to deep brain stimulation surgery in a 54-year-old Caucasian man.

Conclusion

The characteristic neuroleptic malignant syndrome symptoms can be attributed to other, more common causes associated with deep brain stimulation treatment for Parkinson's disease, thus requiring a high index of clinical suspicion to timely establish the correct diagnosis. As more centers become eligible to perform deep brain stimulation, neurologists and neurosurgeons alike should be aware of this potentially fatal complication. Timely activation of the deep brain stimulation system may be important in accelerating the patient's recovery.

Infected internal pulse generator: Treatment without removal

Background:

One of the rare but devastating complications of deep brain stimulation (DBS) is internal pulse generator (IPG) infection. In the majority of the cases, removal of the device is required, despite appropriate antibiotic therapy. We demonstrate that eradication of an IPG infection is feasible without removal of the IPG device.

Case Description:

This article reports the authors’ experience on two patients who underwent DBS for advanced Parkinson's disease (PD) and, subsequently, suffered from infection and skin breakdown over the IPG. The patients were treated with antibiotic therapy, surgical revision of the wound, intraoperative disinfection of the IPG and relocation of the subcutaneous pocket. In both cases, the infection was eradicated and DBS therapy was continued uninterrupted.

Conclusion:

Although not generally recommended, DBS IPG may be salvaged in selected cases of superficial device infection. Our experience suggests that it is possible to treat the infection without removing the device. Such an approach decreases the morbidity, duration of hospital stay and health care costs.

High incidence of MGMT and RARbeta promoter methylation in primary glioblastomas: association with histopathological characteristics, inflammatory mediators and clinical outcome

Glioblastomas, the most frequent primary brain tumors in adults, are characterized by a highly aggressive, inflammatory and angiogenic phenotype. Methylation of CpG islands in cancer-related genes may serve as an epigenetic biomarker for glioblastoma diagnosis and prognosis. The aim of this study was to analyze the methylation status of four critical tumor-associated genes (MGMT, RARbeta, RASSF1A, CDH13), and investigate possible links with inflammatory (interleukin [IL]-6, IL-8) and angiogenic mediators (vascular endothelial growth factor [VEGF], cyclooxygenase [COX]-2) and clinical outcome in 23 glioma samples (6 grade II astrocytomas, 17 grade IV glioblastomas). RARbeta and MGMT genes were more frequently methylated in 70.58% and 58.8% of glioblastomas, respectively. RASSF1A and CDH13 displayed a similar methylation frequency (23.52%) in glioblastomas. No gene methylation was observed in grade II astrocytomas. Tumor grade correlated positively with MGMT and RARbeta methylation (P = 0.005 and P = 0.019, respectively) and the extent of necrosis (P = 0.001 and P = 0.003). Interestingly, the marker of chronic inflammation, IL-6, was positively associated with methylation of MGMT (P = 0.004), RARbeta (P = 0.002), and RASSF1A (P = 0.0081) as well as the total number of methylated genes (P < 0.0001), indicating the important role of IL-6 in maintaining promoter methylation of these genes. VEGF expression correlated positively with MGMT and RARbeta methylation although these relationships were of marginal significance (P = 0.0679 and P = 0.0757). Kaplan-Meier univariate survival analysis indicated an unfavorable survival period in patients with MGMT methylation compared with those without methylation (P = 0.0474). Our study highlights the implication of MGMT and RARbeta methylation in the aggressive phenotype of primary glioblastomas. The association of MGMT methylation with clinical outcome indicates its potential prognostic value.

Treatment of idiopathic head drop (camptocephalia) by deep brain stimulation of the globus pallidus internus

Deep brain stimulation of the globus pallidus internus has been shown to be beneficial in a small number of patients suffering from axial dystonias. However, it has not yet been reported as an effective treatment for the alleviation of idiopathic head drop. The authors describe a 49-year-old woman with idiopathic cervical dystonia (camptocephalia) who was unable to raise her head > 30° when standing or sitting; her symptoms would abate when lying down. This disabling neurological condition was treated successfully with bilateral chronic electrical stimulation of the globus pallidus internus.

Analysis of interleukin (IL)-8 expression in human astrocytomas: associations with IL-6, cyclooxygenase-2, vascular endothelial growth factor, and microvessel morphometry

Malignant astrocytomas are highly vascular neoplasms with potent angiogenic activity. The present study aimed to investigate peripheral and local expression of interleukin (IL)-8 in astrocytomas with possible associations to IL-6, cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF) expression, and microvessel morphometry. IL-6- and IL-8-secreting peripheral blood monocytes (PBMCs) were evaluated in 17 glioblastoma (WHO grade IV), 5 anaplastic astrocytoma (WHO grade III), and 6 diffuse astrocytoma patients (WHO grade II), in parallel with 23 healthy controls using enzyme-linked immunosorbent spot (ELISPOT) assay. The IL-8 expression was assessed immunohistochemically in patients' tumor tissue sections and correlated with the expression of COX-2, VEGF, IL-6, and microvessel morphometry (assessed using CD34 antibody). Eighteen cases were also stained for CD31 and used as an additional vessel marker to validate our results regarding microvessel morphometry. IL-6 and IL-8 were highly secreted in the PBMCs of glioma patients compared with controls (p = 0.0001, p < 0.0001, respectively), with a positive correlation between IL-8 expression and secretion levels (p = 0.001). IL-8 immunoreactivity was detected in malignant cells or macrophages in perivascular areas and in pseudopalisading cells around necrosis and was positively correlated with histological grade (p = 0.0175) and tumor necrosis (p = 0.0793). IL-6 and IL-8 expression levels were positively correlated (p = 0.0036) and associated with COX-2 and VEGF expression (IL-6: p = 0.0133, p = 0.065; IL-8: p = 0.0139, p = 0.0101), but not with microvessel morphometry, by either CD31 or CD34. The coordinate expression and topographical relationship of IL-6, IL-8, COX-2, and VEGF in the same tumor areas (e.g., perinecrotic areas) attest to their intimate liaison in terms of cancer-induced angiogenesis, which is probably secondary to the induction of multiple interdependent molecular pathways. Moreover, our study seems to be the first attempt to link IL-8 expression by tumor cells with histological grade, implicating its potent role in gliomagenesis.

Comparative analysis of peripheral and localised cytokine secretion in glioblastoma patients

BACKGROUND

Malignant gliomas are the most common primary brain tumours of both children and adults. The unique aspects of their biology and anatomic site render them refractory to conventional therapeutic strategies such as surgery and chemotherapy. Significant attention has been given, recently, to immunotherapy which, although promising in preclinical studies, has not yet enhanced the survival of patients with glioblastomas.

METHODS

To further understand the immunobiology of glioblastomas in clinical settings, we examined the secretion of four main cytokines in the peripheral blood and in primary cell cultures of 33 human glioblastoma patients. An ELISPOT methodology was used for the first time to examine Th1, and Th2 cytokine secretion from both peripheral lymphocytes and glioma tumour cells.

RESULTS

Th1 cytokines (tumour necrosis factor (TNF-alpha), interferon (IFN-gamma) were markedly reduced compared to control levels (P=0.01 and P<0.001, respectively), whereas in contrast, Th2 (interleukin (IL)-4 and IL-10) were strongly expressed in both peripheral lymphocytes and glioma cell cultures (P=0.05 and P<0.001, respectively).

CONCLUSION

This pattern indicates an 'immunosuppressive status' in glioblastomas which is related to their origination and the evasion of glioma cells from immune surveillance and could account for the failure of immunotherapy in such tumours. Furthermore, ELISPOT methodology can be used for monitoring of cytokine secretion from tumour cells, in addition to the well-established peripheral cytokine secretion.

Impact of age on complications and outcome in meningioma surgery

BACKGROUND

Surgery for benign brain tumors in elderly patients without severe general health problems is an acceptable practice, as results are comparable with the ones of younger patients. Nevertheless, the hypothesis that operative complications and perioperative incidents could differ between the 2 age groups should be controlled; and age-specific strategies in operative technique and perioperative care may be useful.

METHODS

Medical records of 348 patients were reviewed. Demographic data (age, sex), rate of excision, complications of the immediate postoperative period, neurological outcome, and mortality were recorded; and statistical evaluation comparing 2 age groups (19-64 and 65-84 years of age) was performed.

RESULTS

The "young" age group consisted of 240 patients, whereas the "elderly" one had 108. Tumor removal rate was not significantly different in the 2 groups. The elderly age group included significantly more "complicated cases." Regarding each complication, postoperative hematoma, infections, and deep vein thrombosis were more frequent in elderly patients, presenting various degrees of statistical significance, whereas postoperative brain edema, hydrocephalus, and cardiorespiratory incidents presented no statistically significant difference. Finally, more elderly patients presented neurological deterioration, although mortality was not significantly different.

CONCLUSIONS

Operation for intracranial meningioma in elderly patients is justified as long as detailed preoperative evaluation is performed. Planning of modified protocols including intraoperative technical aspects, careful use of steroids antibiotics, and prophylactic low molecular weight heparin, and early mobilization is necessary for optimizing operative outcome of elderly patients.

Application of the ELISPOT method for comparative analysis of interleukin (IL)-6 and IL-10 secretion in peripheral blood of patients with astroglial tumors

Glioblastoma, (grade IV astrocytoma), is characterized by rapid growth and resistance to treatment. Identification of markers of aggressiveness in this tumor could represent new therapeutic targets. Interleukins (IL)-6 and IL-10 may be considered as possible candidates, regulating cell growth, resistance to chemotherapy and angiogenesis. ELISPOT method provides a useful tool for the determination of the exact cell number of peripheral lymphocytes secreting a specific cytokine. IL-6 and IL-10 secretion levels were determined using ELISPOT methodology in peripheral blood mononuclear cells of 18 patients with astrocytic neoplasms (3 grade II and 15 grade IV), in parallel with 18 healthy controls. Additionally, immunohistochemical expression of these two cytokines was performed in paraffin-embedded neoplastic tissue in 12 of these patients. The secretion of IL-6 from peripheral monocytes was significantly higher in glioma patients compared to controls (P = 0.0003). In addition, IL-10 secretion from peripheral mononuclear and tumor cells of glioma patients was also higher as compared to healthy controls (P = 0.0002). Based on immunohistochemical staining, IL-6 expression was localized in tumor cells and macrophages as well as in areas of large ischemic necrosis, while the major source of IL-10 expression in glioblastomas was the microglia/macrophage cells. It is suggested that IL-10 contributes to the progression of astrocytomas by suppressing the patient's immune response, whereas IL-6 provides an additional growth advantage. This study demonstrates for the first time the usefulness of ELISPOT in estimating the secretion of IL-6 and IL-10 from peripheral blood and the correlation of their expression in neoplastic cells.

Connections of the basal ganglia with the limbic system: implications for neuromodulation therapies of anxiety and affective disorders

The basal ganglia are best known for their role in motor planning and execution. However, it is currently widely accepted that they are also involved in cognitive and emotional behaviors. Parts of the basal ganglia play a key role in reward and reinforcement, addictive behaviors and habit formation. Pathophysiological processes underlying psychiatric disorders such as depression, obsessive compulsive disorder and even schizophrenia involve the basal ganglia and their connections to many other structures and particularly to the prefrontal cortex and the limbic system. In this article, we aim, on the basis of current research, to describe in a succinct manner the most important connections of the basal ganglia with the limbic system which are relevant to normal behaviors but also to psychiatric disorders. Currently, we possess sufficiently powerful tools that enable us to modulate brain networks such as cortex stimulation (CS) or deep brain stimulation (DBS). Notably, neuromodulation of basal ganglia function for the treatment of movement disorders has become a standard practice, which provides insights into the psychiatric problems that occur in patients with movement disorders. It is clear that a sound understanding of the currently available knowledge on the circuits connecting the basal ganglia with the limbic system will provide the theoretical platform that will allow precise, selective and beneficial neuromodulatory interventions for refractory psychiatric disorders.

Skeletal growth factor involvement in the regulation of fracture healing process

Skeletal growth factors are peptides that serve as signalling agents for living cells, thereby participating in the autocrine, paracrine, intracrine and endocrine bioregulation of tissues and organs in human physiology. Growth factors elicit their cellular actions after binding to specific receptors, which are large transmembrane proteins located on target cells. These receptors relay signals via specific intracellular signal transduction pathways capable of regulating gene transcription, thereby modifying cell proliferation, cell function, cell differentiation and apoptosis. Notably, growth factors and their specific receptors are expressed in and around a bone fracture repair site, suggesting strongly that they play a significant role in the physio/pathology of fracture healing. Conceivably, fine adjustments of specific growth factor activity during the different stages of the fracture healing process can serve as potential therapeutic targets, enhancing bone repair capacity and reducing irregularities of the healing process.