DKK3 Expression in Glioblastoma: Correlations with Biomolecular Markers.

Glioblastoma is the most common malignant primary tumor of the CNS. The prognosis is dismal, with a median survival of 15 months. Surgical treatment followed by adjuvant therapies such as radiotherapy and chemotherapy characterize the classical strategy. The WNT pathway plays a key role in cellular proliferation, differentiation, and invasion. The DKK3 protein, capable of acting as a tumor suppressor, also appears to be able to modulate the WNT pathway. We performed, in a series of 40 patients, immunohistochemical and Western blot evaluations of DKK3 to better understand how the expression of this protein can influence clinical behavior. We used a statistical analysis, with correlations between the expression of DKK3 and overall survival, age, sex, Ki-67, p53, and MGMT and IDH status. We also correlated our data with information included in the cBioPortal database. In our analyses, DKK3 expression, in both immunohistochemistry and Western blot analyses, was reduced or absent in many cases, showing downregulation. To date, no clinical study exists in the literature that reports a potential correlation between IDH and MGMT status and the WNT pathway through the expression of DKK3. Modulation of this pathway through the expression of DKK3 could represent a new tailored therapeutic strategy in the treatment of glioblastoma.

The Role of Nanotechnologies in Brain Tumors.

The treatment of glioma remains one of the most interesting topics in neurooncology. Glioblastoma multiforme is the most aggressive and prevalent malignant brain tumor. Nowadays, technologies and new tools are helping the neurosurgeons to define a tailored surgery. However, there are few pharmaceutical strategies in operated and nonoperated patients. There are still few anticancer drugs approved by FDA and EMA. Moreover, these drugs are not so effective and have a lot of side effects due to their toxicity. Nanoparticles are a new strategy which could help to create and carry new drugs. In fact, NPs improve the pharmacokinetic properties of anticancer drugs, reduce side-effects, and increase drug half-life and its selectivity. Nanoparticle drug delivery system has been studied for targeting different molecular biomarkers and signaling pathways. Furthermore, the first problem of anticancer drugs in the treatment of gliomas is penetrating the blood brain barrier which represents an insurmountable wall for most of synthetic and natural particles. In the last 15 years, a lot of researches tried to design a perfect nanoparticle both able to cross blood-brain barrier and to selectively target glioma cells, unfortunately, without great results. In vivo human trials are still ongoing and many of them have already failed. In this chapter we evaluate the effectiveness of nanotechnologies in the treatment of brain tumors. There is not yet, currently, a nanoparticle drug designed for the treatment of gliomas approved by FDA and EMA. Advancements in discovery of molecular characteristics of tumors lead to the development of targeted nanoparticles that are tested in numerous in vitro and in vivo studies on gliomas. Novel and repurposed drugs, as well as novel drug combinations, have also been already studied but those are not included in this chapter because the carried drugs (active substances) are not included among the approved anticancer drug used in the treatment of gliomas.

The Role of Nanotechnology in Spinal Cord Tumors.

The efficacy of current multimodal therapeutic strategies in spinal cord tumors is limited by the lack of specific therapies. Importantly, sufficient amount of therapeutic materials should be concentrated in tumors in order to be efficient. Overcoming the blood-brain barrier is the major obstacle for chemotherapeutics, which cannot reach the tumor bed in efficacious doses. The intrinsic properties of nanoparticles make them suitable for activating numerous processes both at the cellular and subcellular levels, making them good candidates to be used for different purposes in medicine. Furthermore, the adaptability characteristic of NPs may enable them to pass through the blood-brain barrier and transport different pharmacological compounds. Nanoparticle systems provide prolonged drug delivery directly to the tumor or by functionalizing the material surface with peptides and ligands allowing the drug-loaded material to specifically target the tumor cells. In this chapter, various preclinical and/or clinical studies in treatment of spinal cord tumors are discussed.

Impact of Heavy Metals on Glioma Tumorigenesis.

Recently, an increase in the incidence of brain tumors has been observed in the most industrialized countries. This event triggered considerable interest in the study of heavy metals and their presence in the environment (air, water, soil, and food). It is probable that their accumulation in the body could lead to a high risk of the onset of numerous pathologies, including brain tumors, in humans. Heavy metals are capable of generating reactive oxygen, which plays a key role in various pathological mechanisms. Alteration of the homeostasis of heavy metals could cause the overproduction of reactive oxygen species and induce DNA damage, lipid peroxidation, and the alteration of proteins. A large number of studies have shown that iron, cadmium, lead, nickel, chromium, and mercury levels were significantly elevated in patients affected by gliomas. In this study, we try to highlight a possible correlation between the most frequently encountered heavy metals, their presence in the environment, their sources, and glioma tumorigenesis. We also report on the review of the relevant literature.

Medulloblastoma of the adult: results from a multicenter retrospective study by AINO (Italian Association of Neuro-Oncology) and SIN (Italian Society of Neurology).

INTRODUCTION: Medulloblastoma (MB) is the most common primary malignant intracranial tumor in childhood, but it is very rare in adults, and for this reason, the optimal treatment has not yet been defined. We designed a multicentric study in order to define relevant outcome measures for future prospective studies. MATERIALS AND METHODS: The project involved 10 Italian centers. The database shared among the centers contains epidemiological, diagnostic (radiological and histological/molecular), therapeutic, recurrence information, and survival data. RESULTS: A total of 152 patients (102 males and 50 females, median age 32) were included in the study. Twenty-three of 152 patients had a diagnosis of classic medulloblastoma, 52/152 had desmoplastic/extensive nodularity, 2/152 had large-cell anaplastic medulloblastoma, and the remaining had diagnoses not otherwise specified. Almost all patients underwent craniospinal irradiation after surgery; in 85.5% of patients, adjuvant chemotherapy, mainly platinum- and etoposide-based chemotherapy, was performed immediately after RT. Upon recurrence, most patients were retreated with various chemotherapy regimens, including intrathecal chemotherapy in patients with leptomeningeal dissemination. The overall survival (OS) rate at 5 years was 73.3% (95% CI, 65.0-80.0%). The median OS for the whole group of patients was 112 months. CONCLUSIONS: The data collected were mainly consistent with the literature. A limitation of this study was the large number of patients lost to follow-up and the lack of molecular data for most patients diagnosed until 2010. An important challenge for the future will be MB biologic characterization in adults, with the identification of specific genetic patterns. It will be important to have more national and international collaborations to provide evidence-based management strategies that attempt to obtain a standard of care.

Unusual Case of Posterior Fossa Extradural Hematoma in a Child: Review of the Literature.

INTRODUCTION: Posterior fossa extradural hematoma (PFEH) is a rare pathology often due to nuchal region trauma. In children, PFEH causes rapid decline of the neurological status also for brain stem compression. Early brain computed tomography (CT) scan is necessary suspicious for PFEH. Most patients need surgical evacuation. CASE PRESENTATION: In this article, we present a 5-year-old patient arrived for meningitis that came out in favor of PFEH after an accurate history record. DISCUSSION/CONCLUSION: Accurate anamnestic records, especially in pediatric patients, prevent from misleading clinic and neurological presentation. Brain CT scan is an indispensable diagnostic tool in order to promptly recognize and treat PFEH considering that rapid cognitive impairment of patients raises the risk of mortality and morbidity.

High p-mTOR expression is associated with recurrence and shorter disease-free survival in atypical meningiomas.

Due to their widely variable clinical behavior, the post-surgical treatment of atypical meningiomas is controversial. Therefore, prognostic factors able to identify high-risk cases, which may benefit from adjuvant treatments, are warranted. Mammalian target of rapamycin (mTOR) belongs to the PI3K-AKT pathway. Its phosphorylated form (p-mTOR Ser2448) is involved in cell growth, differentiation and tumorigenesis. The aim of this study was to evaluate p-mTOR Ser2448 expression and its eventual correlation with clinicopathological features, recurrence, or disease-free survival (DFS), in atypical meningiomas. p-mTOR immunohistochemical expression was analyzed in 48 atypical meningiomas and correlated with clinicopathological parameters and with DFS. Eighty-one percent of atypical meningiomas expressed p-mTOR Ser2448. High immuno-expression was significantly associated with recurrences (P = 0.01) and lower DFS (P = 0.01). The presence of brain invasion, high mitotic index plus sheeting, and Simpson grade were significant and independent prognostic variables at multivariate analysis. p-mTOR Ser2448 is expressed in atypical meningiomas. High expression predicts development of recurrences and shorter DFS in patients affected by these tumors. Since p-mTOR Ser2448 is a target of anti-neoplastic drugs, evaluation of its expression may be used, not only to identify atypical meningiomas at higher risk of recurrence, but also to select those to submit to adjuvant targeted chemotherapy.

Classification of human meningiomas: lights, shadows, and future perspectives.

Meningiomas represent the most common primary tumors of the central nervous system (CNS) in adulthood. They are currently classified into several histotypes and into three grades of malignancy according to the criteria of the World Health Organization (WHO) classification of tumors of the CNS. WHO histological grade is currently the most significant morphological predictor of recurrence risk of meningiomas. For this reason, it is fully taken into consideration in postsurgical therapeutic decision making in patients with meningioma. However, the main drawback of the WHO grading system system is that criteria for its assessment are rather subjective and poorly standardized. Hence, additional factors are warranted to predict recurrence risk of meningiomas, so that patients may actually receive the most appropriate therapy. In recent years, biomolecular pathogenesis of meningiomas has been partially clarified, and many efforts have been made in the identification of molecular factors associated with recurrence risk of meningioma. Here we review WHO criteria currently used for classification of meningiomas and discuss on pitfalls and limits of grading assessment. In addition we present the latest advancement in the knowledge of biomolecular alterations involved in the pathogenesis and progression of meningiomas. Similarly to what has already happened for gliomas, a novel classification integrating histology and molecular information might overcome the limits of histological classification in terms of reproducibility as well as of prognostic and predictive relevance. © 2016 Wiley Periodicals, Inc.

Atypical teratoid rhabdoid tumor involving the nasal cavities and anterior skull base.

Rhabdoid tumors are a spectrum of neoplasias composed of cells which show rhabdoid morphology but are devoid of skeletal muscle differentiation. These tumors are characterized by inactivation of the INI1/SMARCB1 gene and they have been described in virtually every anatomical site, including the central nervous system (CNS) and sinonasal tract. Rhabdoid tumor of the CNS was named atypical teratoid rhabdoid tumor (ATRT) and it mainly affects children under the age of 3 years with supra- or infra-tentorial location.Herein we report the first case of ATRT infiltrating the nasal cavities and skull base in an adolescent. Due to its unusual location, differential diagnosis was challenging and included several other entities such as sinonasal carcinoma or meningioma. Awareness that ATRT may infiltrate the nasal tract and knowledge of its clinico-pathological, immunohistochemical and biomolecular features are essential for its distinction from other rhabdoid tumors which more frequently involve this anatomical site and for appropriate therapeutic management.

ROS and Brain Gliomas: An Overview of Potential and Innovative Therapeutic Strategies.

Reactive oxygen species (ROS) represent reactive products belonging to the partial reduction of oxygen. It has been reported that ROS are involved in different signaling pathways to control cellular stability. Under normal conditions, the correct function of redox systems leads to the prevention of cell oxidative damage. When ROS exceed the antioxidant defense system, cellular stress occurs. The cellular redox impairment is strictly related to tumorigenesis. Tumor cells, through the generation of hydrogen peroxide, tend to the alteration of cell cycle phases and, finally to cancer progression. In adults, the most common form of primary malignant brain tumors is represented by gliomas. The gliomagenesis is characterized by numerous molecular processes all characterized by an altered production of growth factor receptors. The difficulty to treat brain cancer depends on several biological mechanisms such as failure of drug delivery through the blood-brain barrier, tumor response to chemotherapy, and intrinsic resistance of tumor cells. Understanding the mechanisms of ROS action could allow the formulation of new therapeutic protocols to treat brain gliomas.

p-CREB expression in human meningiomas: correlation with angiogenesis and recurrence risk.

Despite total surgical resection, a percentage of meningiomas do unexpectedly recur. At present the prediction of recurrence risk and the management of recurrent tumours represent major issues in the patients affected by meningiomas. The present study aims at investigating the prognostic value of the expression of the phosphorylated transcription factor cyclic AMP responsive element binding protein (p-CREB) in a series of meningiomas of different histotype and grade. While no p-CREB expression was found in specimens of normal leptomeninges, 71 % of meningiomas in our cohort expressed p-CREB. In addition, nuclear expression of p-CREB was present in the endothelia of tumor vessels in all of the meningiomas, but not in the vessels of the non-neoplastic meninges. High expression of p-CREB was significantly more frequent in meningiomas showing atypical, chordoid or microcystic histotype (P = 0.0003), high histological grade (P < 0.0001), high Ki-67 labeling index (P = 0.0001), high microvessel density counts (P < 0.0001) and high vascular endothelial growth factor expression (P = 0.0113). In addition, high p-CREB expression was significantly associated with the development of recurrences (P = 0.0031) and it was a significant negative, albeit not independent, prognostic factor for disease free survival in patients with meningiomas submitted to complete surgical removal (P = 0.0019). In conclusion, we showed that p-CREB is expressed in human meningiomas and that it represents a significant predictor of recurrence risk in these tumors. Due to its high expression in more aggressive tumors and in the tumor vessels, it may represent a novel therapeutic target in meningiomas.

Heavy metals and epigenetic alterations in brain tumors.

Heavy metals and their derivatives can cause various diseases. Numerous studies have evaluated the possible link between exposure to heavy metals and various cancers. Recent data show a correlation between heavy metals and aberration of genetic and epigenetic patterns. From a literature search we noticed few experimental and epidemiological studies that evaluate a possible correlation between heavy metals and brain tumors. Gliomas arise due to genetic and epigenetic alterations of glial cells. Changes in gene expression result in the alteration of the cellular division process. Epigenetic alterations in brain tumors include the hypermethylation of CpG group, hypomethylation of specific genes, aberrant activation of genes, and changes in the position of various histones. Heavy metals are capable of generating reactive oxygen assumes that key functions in various pathological mechanisms. Alteration of homeostasis of metals could cause the overproduction of reactive oxygen species and induce DNA damage, lipid peroxidation, and alteration of proteins. In this study we summarize the possible correlation between heavy metals, epigenetic alterations and brain tumors. We report, moreover, the review of relevant literature.

Epigenetic effects of cadmium in cancer: focus on melanoma.

Cadmium is a highly toxic heavy metal, which has a destroying impact on organs. Exposure to cadmium causes severe health problems to human beings due to its ubiquitous environmental presence and features of the pathologies associated with pro-longed exposure. Cadmium is a well-established carcinogen, although the underlying mechanisms have not been fully under-stood yet. Recently, there has been considerable interest in the impact of this environmental pollutant on the epigenome. Be-cause of the role of epigenetic alterations in regulating gene expression, there is a potential for the integration of cadmium-induced epigenetic alterations as critical elements in the cancer risk assessment process. Here, after a brief review of the ma-jor diseases related to cadmium exposure, we focus our interest on the carcinogenic potential of this heavy metal. Among the several proposed pathogenetic mechanisms, particular attention is given to epigenetic alterations, including changes in DNA methylation, histone modifications and non-coding RNA expression. We review evidence for a link between cadmium-induced epigenetic changes and cell transformation, with special emphasis on melanoma. DNA methylation, with reduced expression of key genes that regulate cell proliferation and apoptosis, has emerged as a possible cadmium-induced epigenetic mechanism in melanoma. A wider comprehension of mechanisms related to this common environmental contaminant would allow a better cancer risk evaluation.

Immuno-expression of endoglin and smooth muscle actin in the vessels of brain metastases. Is there a rational for anti-angiogenic therapy?

Despite ongoing clinical trials, the efficacy of anti-angiogenic drugs for the treatment of brain metastases (BM) is still questionable. The lower response rate to anti-angiogenic therapy in the presence of BM than in metastatic disease involving other sites suggests that BM may be insensitive to these drugs, although the biological reasons underlining this phenomenon are still to be clarified. With the aim of assessing whether the targets of anti-angiogenic therapies are actually present in BM, in the present study, we analyzed the microvessel density (MVD), a measure of neo-angiogenesis, and the vascular phenotype (mature vs. immature) in the tumor tissue of a series of BM derived from different primary tumors. By using immunohistochemistry against endoglin, a specific marker for newly formed vessels, we found that neo-angiogenesis widely varies in BM depending on the site of the primary tumor, as well as on its histotype. According to our results, BM from lung cancer displayed the highest MVD counts, while those from renal carcinoma had the lowest. Then, among BM from lung cancer, those from large cell and adenocarcinoma histotypes had significantly higher MVD counts than those originating from squamous cell carcinoma (p=0.0043; p=0.0063). Of note, MVD counts were inversely correlated with the maturation index of the endoglin-stained vessels, reflected by the coverage of smooth muscle actin (SMA) positive pericytes (r=-0.693; p<0.0001). Accordingly, all the endoglin-positive vessels in BM from pulmonary squamous cell carcinoma and renal carcinoma, displayed a mature phenotype, while vessels with an immature phenotype were found in highly vascularized BM from pulmonary large cell and adenocarcinoma. The low MVD and mature phenotype observed in BM from some primary tumors may account for their low sensitivity to anti-angiogenic therapies. Although our findings need to be validated in correlative studies with a clinical response, this should be taken into account in therapeutic protocols in order to avoid the adverse effects of useless therapies.

Brain Stem Glioma Recurrence: Exploring the Therapeutic Frontiers.

Gliomas of the brainstem represent a small percentage of central nervous system gliomas in adults. Due to the proximity of the tumor to critical structures, radical surgery is highly challenging and limited to selected cases. In addition, postoperative treatments, which become exclusive to non-operable patients, do not guarantee satisfactory disease control, making the progression of the disease inevitable. Currently, there is a lack of therapeutic options to control tumor growth after the diagnosis of recurrence. The rarity of these tumors, their distinct behavioral characteristics, and the limited availability of tumor tissue necessary for the development of prognostic and predictive biomarkers contribute to the absence of a standardized approach for treating recurrent brainstem gliomas. A salvage radiotherapy (RT) retreatment could represent a promising approach for recurrent brainstem gliomas. However, to date, it has been mainly evaluated in pediatric cases, with few experiences available to assess the most appropriate RT dose, safety, and clinical responses in adult patients. This comprehensive review aims to identify instances of adult patients with recurrent brainstem gliomas subjected to a secondary course of RT, with a specific focus on the analysis of treatment-related toxicity and outcomes. Through this investigation, we endeavor to contribute valuable insights into the viability and efficacy of salvage RT retreatment in managing recurrent brainstem gliomas in the adult population.

Local therapy in glioma: An evolving paradigm from history to horizons (Review).

Despite the implementation of multimodal treatments after surgery, glioblastoma (GBM) remains an incurable disease, posing a significant challenge in neuro-oncology. In this clinical setting, local therapy (LT), a developing paradigm, has received significant interest over time due to its potential to overcome the drawbacks of conventional therapy options for GBM. The present review aimed to trace the historical development, highlight contemporary advances and provide insights into the future horizons of LT in GBM management. In compliance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols criteria, a systematic review of the literature on the role of LT in GBM management was conducted. A total of 2,467 potentially relevant articles were found and, after removal of duplicates, 2,007 studies were screened by title and abstract (Cohen's κ coefficient=0.92). Overall, it emerged that 15, 10 and 6 clinical studies explored the clinical efficiency of intraoperative local treatment modalities, local radiotherapy and local immunotherapy, respectively. GBM recurrences occur within 2 cm of the radiation field in 80% of cases, emphasizing the significant influence of local factors on recurrence. This highlights the urgent requirement for LT strategies. In total, three primary reasons have thus led to the development of numerous LT solutions in recent decades: i) Intratumoral implants allow the blood-brain barrier to be bypassed, resulting in limited systemic toxicity; ii) LT facilitates bridging therapy between surgery and standard treatments; and iii) given the complexity of GBM, targeting multiple components of the tumor microenvironment through ligands specific to various elements could have a synergistic effect in treatments. Considering the spatial and temporal heterogeneity of GBM, the disease prognosis could be significantly improved by a combination of therapeutic strategies in the era of precision medicine.

Glioblastoma and Internal Carotid Artery Calcium Score: A Possible Novel Prognostic Partnership?

Purpose: Clinical evidence suggests an association between comorbidities and outcome in patients with glioblastoma (GBM). We hypothesised that the internal carotid artery (ICA) calcium score could represent a promising prognostic biomarker in a competing risk analysis in patients diagnosed with GBM. Methods: We validated the use of the ICA calcium score as a surrogate marker of the coronary calcium score in 32 patients with lung cancer. Subsequently, we assessed the impact of the ICA calcium score on overall survival in GBM patients treated with radio-chemotherapy. Results: We analysed 50 GBM patients. At the univariate analysis, methyl-guanine-methyltransferase gene (MGMT) promoter methylation (p = 0.048), gross total tumour resection (p = 0.017), and calcium score (p = 0.011) were significant prognostic predictors in patients with GBM. These three variables also maintained statistical significance in the multivariate analysis. Conclusions: the ICA calcium score could be a promising prognostic biomarker in GBM patients.

Embolized meningiomas: risk of overgrading and neo-angiogenesis.

Pre-operative embolization (POE) of meningiomas may induce histological changes which simulate malignancy, possibly resulting in overgrading. Aims of the present study were to identify clues to distinguish malignancy-related features from POE-related changes and to test for overgrading the grading scheme currently in use, in embolized meningiomas. In addition, we aimed to analyze whether the POE procedure may stimulate neo-angiogenesis in meningiomas. The histological features of a series of embolized meningiomas were evaluated and considered for grading assessment. In the same cases neo-angiogenesis was quantified by the evaluation of microvessel density (MVD) and correlated with the interval between POE and surgery. Necrosis and macronucleoli represented common findings in embolized meningiomas. Nonetheless, in most of the cases, necrosis showed an abrupt line of demarcation from the viable tumour tissue, and macronucleoli were restricted to peri-necrotic areas. Suggesting that these were POE-associated changes, exclusion of necrotic areas with an abrupt line of transition and focal macronucleoli from grading assessment resulted in increased specificity and positive predictive value in the identification of recurring meningiomas. In our cohort, MVD significantly increased with the time between POE and surgery, suggesting that POE procedure may induce neo-angiogenesis in meningiomas. In conclusion, a risk of overgrading there exists in embolized meningiomas, as a consequence of the frequent evidence of necrosis and prominent nucleoli in these tumours. In order to avoid overgrading, we suggest that necrosis showing an abrupt line of demarcation and focal peri-necrotic macronucleoli are not included in grading assessment. Also, caution should be used in the interpretation of MVD as a prognostic factor in embolized meningioma, as it may also result from POE procedure.

Advanced virtual magnetic resonance imaging (MRI) techniques in neurovascular conflict: bidimensional image fusion and virtual cisternography.

PURPOSE: The aim of this study was to evaluate the advantages and limits of virtual magnetic resonance techniques in planning surgery for microvascular decompression in patients with neurovascular conflict. MATERIALS AND METHODS: Between December 2010 and December 2011, we prospectively observed 32 patients (30 with trigeminal neuralgia and two with hemifacial spasm), with a suspected clinical diagnosis of neurovascular conflict. To assess the contact between nerve and vessel, magnetic resonance imaging (MRI) by three-dimensional (3D) constructive interference in steady state (CISS) and high-resolution MR angiography (MRA) were performed in all cases. Moreover, we performed presurgical simulation of microvascular decompression using MR two-dimensional image fusion and virtual cisternography. The neuroradiological findings were compared with the surgical findings. RESULTS: In all cases, we demonstrated the anatomical relations between cranial nerves and offending vessels with an optimal correlation between radiological and surgical patterns. CONCLUSIONS: Advanced virtual MRI techniques, such as image fusion and virtual cisternography, are able to depict the complex anatomical relationships between neural and vascular structures within the cisternal spaces of the skull base. These techniques can be considered an optimal presurgical tool to support traditional MRI evaluation of this region.