Bevacizumab plus hypofractionated radiotherapy versus radiotherapy alone in elderly patients with glioblastoma: the randomized, open-label, phase II ARTE trial.

Background: The addition of bevacizumab to temozolomide-based chemoradiotherapy (TMZ/RT â†’ TMZ) did not prolong overall survival (OS) in patients with newly diagnosed glioblastoma in phase III trials. Elderly and frail patients are underrepresented in clinical trials, but early reports suggested preferential benefit in this population. Patients and methods: ARTE was a 2 : 1 randomized, multi-center, open-label, non-comparative phase II trial of hypofractionated RT (40 Gy in 15 fractions) with bevacizumab (10 mg/kg×14 days) (arm A, N = 50) or without bevacizumab (arm B, N = 25) in patients with newly diagnosed glioblastoma aged ≥65 years. The primary objective was to obtain evidence for prolongation of median OS by the addition of bevacizumab to RT. Response was assessed by RANO criteria. Quality of life (QoL) was monitored by the EORTC QLQ-C30/BN20 modules. Exploratory studies included molecular subtyping by 450k whole methylome and gene expression analyses. Results: Median PFS was longer in arm A than in arm B (7.6 and 4.8 months, P = 0.003), but OS was similar (12.1 and 12.2 months, P = 0.77). Clinical deterioration was delayed and more patients came off steroids in arm A. Prolonged PFS in arm A was confined to tumors with the receptor tyrosine kinase (RTK) I methylation subtype (HR 0.25, P = 0.014) and proneural gene expression (HR 0.29, P = 0.025). In a Cox model of OS controlling for established prognostic factors, associations with more favorable outcome were identified for age <70 years (HR 0.52, P = 0.018) and Karnofsky performance score 90%-100% (HR 0.51, P = 0.026). Including molecular subtypes into that model identified an association of the RTK II gene methylation subtype with inferior OS (HR 1.73, P = 0.076). Conclusion: Efficacy outcomes and exploratory analyses of ARTE do not support the hypothesis that the addition of bevacizumab to RT generally prolongs survival in elderly glioblastoma patients. Molecular biomarkers may identify patients with preferential benefit from bevacizumab. Clinical trial registration number: NCT01443676.

Bevacizumab may improve quality of life, but not overall survival in glioblastoma: an epidemiological study.

Background: The vascular endothelial growth factor antibody bevacizumab (Avastin®), received approval for the treatment of recurrent glioblastoma in many countries including the USA and Switzerland, but not the European Union, in 2009. Here, we explored the hypothesis that the approval of bevacizumab improved outcome with glioblastoma on a population level. Patients and methods: The prognostic significance of epidemiological, molecular genetic, and clinical data including treatment for glioblastoma patients diagnosed from 2010 to 2014 in the Canton of Zurich, Switzerland, was retrospectively analyzed using log-rank test and Cox proportional hazards models. Data were compared with data for the years 2005-2009. Results: In total, 310 glioblastoma patients were identified in the years 2010-2014. Median overall survival was 13.5 months for patients with known isocitrate dehydrogenase (IDH) wild-type (wt) (IDH1R132H-non-mutant) tumors (N = 248), compared with 11.3 months for IDH wt patients (P = 0.761) before (2005-2009). In the IDH wt cohort, bevacizumab use at any time increased from 19% in 2005-2009 to 49% in 2010-2014. Multivariate analysis did not identify bevacizumab exposure at any time to be associated with survival. Yet, upon the second-line treatment, baseline doses of corticosteroids were reduced by more than half in 83% of patients on bevacizumab compared with 48% of the patients treated with bevacizumab-free regimens (P = 0.007). Conclusion: This epidemiological study of a small, but clinically well-annotated patient cohort fails to support the assumption that the strong increase of bevacizumab use since 2010 improved survival in glioblastoma although clinical benefit associated with decreased steroid use may have been achieved.

The aryl hydrocarbon receptor links integrin signaling to the TGF-ß pathway.

Glioblastoma is the most common and aggressive form of intrinsic brain tumor. Transforming growth factor (TGF)-ß represents a central mediator of the malignant phenotype of these tumors by promoting invasiveness and angiogenesis, maintaining tumor cell stemness and inducing profound immunosuppression. Integrins, which are highly expressed in glioma cells, interact with the TGF-ß pathway. Furthermore, a link has been described between activity of the transcription factor aryl hydrocarbon receptor (AhR) and TGF-ß expression. Here we demonstrate that integrin inhibition, using αv, ß3 or ß5 neutralizing antibodies, RNA interference-mediated integrin gene silencing or pharmacological inhibition by the cyclic RGD peptide EMD 121974 (cilengitide) or the non-peptidic molecule GLPG0187, inhibits AhR activity. These effects are independent of cell detachment or cell density. While AhR mRNA expression was not affected by integrin inhibition, AhR total and nuclear protein levels were reduced, suggesting that integrin inhibition-mediated regulation of AhR may occur at a post-transcriptional level. AhR-null astrocytes, AhR-null hepatocytes or glioblastoma cells with a transiently silenced AhR gene showed reduced sensitivity to integrin inhibition-mediated alterations in TGF-ß signaling, indicating that AhR mediates integrin control of the TGF-ß pathway. Accordingly, there was a significant correlation of αv integrin levels with nuclear AhR and pSmad2 levels as determined by immunohistochemistry in human glioblastoma in vivo. In summary, this study identifies a signaling network comprising integrins, AhR and TGF-ß and validates integrin inhibition as a promising strategy not only to inhibit angiogenesis, but also to block AhR- and TGF-ß-controlled features of malignancy in human glioblastoma.

Depletion of the novel p53-target gene carnitine palmitoyltransferase 1C delays tumor growth in the neurofibromatosis type I tumor model.

Despite the prominent pro-apoptotic role of p53, this protein has also been shown to promote cell survival in response to metabolic stress. However, the specific mechanism by which p53 protects cells from metabolic stress-induced death is unknown. Earlier we reported that carnitine palmitoyltransferase 1C (CPT1C), a brain-specific member of a family of mitochondria-associated enzymes that have a central role in fatty acid metabolism promotes cell survival and tumor growth. Unlike other members of the CPT family, the subcellular localization of CPT1C and its cellular function remains elusive. Here, we report that CPT1C is a novel p53-target gene with a bona fide p53-responsive element within the first intron. CPT1C is upregulated in vitro and in vivo in a p53-dependent manner. Interestingly, expression of CPT1C is induced by metabolic stress factors such as hypoxia and glucose deprivation in a p53 and AMP activated kinase-dependent manner. Furthermore, in a murine tumor model, depletion of Cpt1c leads to delayed tumor development and a striking increase in survival. Taken together, our results indicate that p53 protects cells from metabolic stress via induction of CPT1C and that CPT1C may have a crucial role in carcinogenesis. CPT1C may therefore represent an exciting new therapeutic target for the treatment of hypoxic and otherwise treatment-resistant tumors.

Occult leptomeningeal large cell medulloblastoma in an adult.

OBJECTIVE AND IMPORTANCE: Large cell medulloblastoma is an uncommon malignancy of childhood that often pursues an aggressive clinical course. We report the first case of this entity in an adult that proved to be an unsuspected primary leptomeningeal tumor. CLINICAL PRESENTATION: A 30-year-old man complained of worsening neck pain over the course of 3 months. Neck pain increased a few days prior to admission and a cervical spine CT revealed tonsillar herniation. Cervical spine MRI performed the day prior to admission confirmed the diagnosis of Chiari I malformation and C3-4 disk herniation without spinal cord compression. On the day of admission, the patient became unresponsive and resuscitative measures were unsuccessful. Postmortem examination of the brain was notable for necrotic cerebellar tonsils, but demonstrated no evidence of an intraparenchymal mass lesion. Microscopic examination of the cerebellum revealed discohesive neoplastic cells, which showed characteristic dot-like immunoreactivity for synaptophysin, diagnostic of large cell medulloblastoma within the subarachnoid space. CONCLUSIONS: Our experience with this unique case illustrates the challenges of diagnosing a primary leptomeningeal neoplasm. This case also underscores the importance of maintaining a high degree of suspicion for leptomeningeal neoplasms in patients who present with imaging studies suspicious for Chiari I malformation.

Congenital ependymoblastoma arising in the sacrococcygeal soft tissue: a case study.

Ependymoblastomas are distinct embryonal tumors of the central nervous system reported only rarely in the literature. Most examples arise in young children under the age of 2 years, in the supratentorial compartment, and may or may not be related to the ventricular system. We report the case of a one-day-old infant who presented with a 6.4 x 5.6 x 3.5 cm ruptured buttock mass. Ultrasound demonstrated a solid mass at the base of the spine that displaced the bladder anteriorly with resultant hydronephrosis. Magnetic resonance images confirmed the presence of a solid mass surrounding the lower sacrum with an internal component partially encircling and deviating the rectum. Histopathological evaluation confirmed the diagnosis of ependymoblastoma. Of note, immunohistochemical analysis revealed diffuse staining with vimentin and patchy expression of synaptophysin, glial fibrillary acidic protein, neurofilament proteins, neuron-specific enolase, CD99 and nestin. On the 42nd day of life, chemotherapy was initiated with a modified Children's Oncology Group (COG) AGCT-01P1 (cyclophosphamide, cisplatin, 70% etoposide, no bleomycin) regimen. The authors describe their experience and review the literature, emphasizing that ependymoblastomas should be considered in the differential diagnosis of sacral masses in the newborn.

Rare primary CNS anaplastic large cell lymphoma in an immunocompetent adult: a clinical-pathologic case report and review case of the literature.

OBJECTIVE AND IMPORTANCE: Isolated anaplastic large cell lymphoma (ALCL) presenting in the primary central nervous system is distinctly uncommon. The authors describe a case that clinically and radiographically simulated a primary glial neoplasm. CLINICAL PRESENTATION: A 39-year-old immunocompetent male presented with seizures and a rapidly enlarging right occipital/parietal lesion. Magnetic resonance images demonstrated a right occipitoparietal lesion, hypodense on T1WI, with patchy contrast enhancement with gadolinium and significant white matter edema pattern on T2WI along with mass effect and midline shift. INTERVENTION: The patient underwent a frameless stereotactic assisted needle biopsy. There appeared to be a clear demarcation between white matter and tumor with no obvious necrosis. Biopsy showed a proliferation of single cells and poorly cohesive groups of cells with large, pleomorphic nuclei, many containing prominent nucleoli, and a moderate amount of cytoplasm. Immunohistochemical staining revealed CD-30 and ALK-positivity typical of ALCL, a rare form of T-cell lymphoma. An extensive workup revealed neither systemic disease nor evidence of immunocompromise. CONCLUSION: Reported in less than 20 patients, primary ALCL in an immunocompetent patient is rarely found intracranially; however, its ability to mimic glial neoplasms as well as other pathologies underlines its importance.

Relationship between radiation injury and Alzheimer-related neurodegenerative changes.

The relationship between radiation injury and other neurodegenerative changes such as the formation of neuritic or diffuse plaques and tangles have received little attention in the literature. In the current study, archival tissue was examined from 485 patients with the diagnosis of either a primary or metastatic brain tumor, who had received radiation therapy between the initial and subsequent pathological study (either surgical or autopsy). Of those cases, 20 were identified that also contained cerebral cortex in both specimens. Sections were stained with the modified Bielschowsky technique and immunohistochemical preparations for beta-amyloid. Contrary to previous reports, the present study did not identify neurodegenerative changes typical of Alzheimer's disease as a consequence of radiation therapy.

Chromogenic in situ hybridization accurately identifies EGFR amplification in small cell glioblastoma multiforme, a common subtype of primary GBM.

Primary glioblastoma multiforme (GBM) commonly overexpresses the epidermal growth factor receptor (EGFR) gene and its ligand-independent mutant, EGFRvIII. Amplification of the EGFR gene has been implicated in the pathogenesis of primary GBM, in particular the small cell phenotype, and this finding may contribute to its aggressive clinical behavior. Anti-EGFR clinical trials for GBM are being conducted, and it would be useful to identify a rapid technique to determine whether EGFR expression and the small cell phenotype are associated with a response to therapy. In the present study we examined 56 cases of GBM using chromogenic in situ hybridization (CISH). CISH analysis and morphology identified 22 small cell (SCGBM) and 22 non-small cell glioblastoma (NSCGBM), and 12 cases of a mixed phenotype. Fourteen cases of SCGBM (14/22) showed EGFR amplification, while only 5 NSCGBM (5/22) cases showed amplification. We have therefore used CISH as an efficient, economic and reliable means for routinely assessing EGFR amplification in GBM, including the small cell variant.

Neuropathology of the brain and spinal cord in human West Nile virus infection.

OBJECTIVE: To describe the histopathology of the brain and spinal cord in human West Nile virus (WNV) infection. MATERIALS AND METHODS: Single case report, including premortem clinical and laboratory findings, and autopsy. RESULTS: An 83-year-old female presented with acute confusion, high fevers, dysarthria and generalized subjective weakness, with decreased deep tendon reflexes and weakness on physical examination. Electromyography showed evidence of a sensorimotor axonal polyneuropathy of the right-sided extremities. She became ventilator-dependent and died after a 2-week ICU stay, following withdrawal of life support. WNV infection was confirmed premortem by detection of IgM antibodies from serum and CSF and postmortem by RT-PCR from brain tissue. Examination of the brain parenchyma showed scattered microglial aggregates accompanied by perivascular chronic inflammation. The leptomeninges showed focal lymphocytic infiltrates. Examination of the spinal cord showed lymphocytic infiltrates in nerve roots and within the cord proper, with focal microglial nodules and neuronophagia in the ventral horns. Special stains were negative for a demyelinating process. General autopsy revealed only emphysema and atelectasis. CONCLUSIONS: The findings in this case suggest direct viral infection of the spinal cord and nerve roots as the mechanism of the flaccid paralysis often observed in patients infected with WNV. Findings are reviewed in comparison with other reports of neuropathologic findings in human WNV infection.

Alpha-internexin expression in medulloblastomas and atypical teratoid-rhabdoid tumors.

OBJECTIVE: To determine whether medulloblastomas and atypical teratoid/rhabdoid tumors express alpha-internexin, an intermediate filament protein that is expressed in normal neurons undergoing maturation and differentiation. MATERIALS AND METHODS: 28 medulloblastomas and 5 atypical teratoid/rhabdoid tumors were examined for the immunohistochemical expression of alpha-internexin, as well as the neuronal markers peripherin and synaptophysin, and glial fibrillary acidic protein. RESULTS: Overall, 21 of 28 medulloblastomas (75%) expressed alpha-internexin. More specifically, alpha-internexin expression was observed in 6 of 10 (60%) classic medulloblastomas, 12 of 14 (86%) desmoplastic medulloblastomas, 2 of 3 (67%) nodular medulloblastomas, and in one medullomyoblastoma. Similarly, 4 of 5 (80%) atypical teratoid/rhabdoid tumors expressed alpha-internexin. The extent of staining for alpha-internexin tended to be less than that of synaptophysin for both medulloblastomas (75% vs 93%) and atypical teratoid/rhabdoid tumors (80% vs 100%). In contrast to alpha-internexin, peripherin was expressed in only 4 medulloblastomas and one atypical teratoid/rhabdoid tumor. CONCLUSIONS: Alpha-internexin is expressed in the majority of medulloblastomas and atypical teratoid/rhabdoid tumors, indicating that these primitive tumors usually exhibit neuronal differentiation.

Infections of the nervous system.

This article surveys common causes and pathologic features of nervous system infections within the general population. Special consideration is given to infections in people with the HIV virus.

Characterization of initiated cells in N-methylnitrosourea-induced carcinogenesis of the CNS in the adult rat.

Glial tumors may originate from the malignant transformation of multipotent glial progenitor cells, but tools to study malignant transformation leading to gliomas are limited by the lack of biological systems that represent early stages of this disease in adult animals. In order to characterize the initiated cells that give rise to gliomas, we have employed the N-methylnitrosourea (MNU) model for induction of brain tumors in adult rats (Rushing et al., 1998). Specifically, we have isolated and cultured transformed (premalignant) cells from normal-appearing brains of rats exposed to MNU for 10 weeks and from histologically abnormal brains of rats exposed to MNU for 15 weeks. We compared them with cells cultured from control animals under identical conditions. Cultured cells were classified according to their morphology, immunophenotype, karyotype, proliferation capacity, and tumorigenicity in athymic mice. Cultures from untreated normal rat brains grew as monolayers and had normal karyotypes (42 X,Y), epithelioid morphology, and slow proliferative capacity (doubling time > 120 h). In contrast, cultured cells from brains of MNU-exposed animals had karyotypes that ranged from normal to highly aneuploid. Aneuploid lines grew rapidly in multilayers (doubling time < 24 h), had differentiated astrocytic or oligodendroglial morphology and immunohistochemical staining profile, and yielded tumors in athymic mice. Initiated cells with minor chromosomal aberrations assumed mixed bipolar or tripolar morphologies in high density cultures, proliferated rapidly, but showed contact inhibition and failed to induce tumors when injected s.c. in athymic mice. In general, lines showing no evidence of chromosomal aberrations had the most epithelioid morphology, proliferated slowly (doubling time > 72 h), and retained strict contact growth inhibition. The presumed undifferentiated glial progenitor cells in culture from either control or MNU-treated rats variably expressed markers such as vimentin, nestin, and NG2 proteoglycan, and they weakly expressed the mature astrocytic or oligodendroglial markers glial fibrillary acidic protein or galactocerbroside, respectively. These cultures differentiated to bipolar-tripolar morphology with concomitant maturation to a GFAP+ or GalC+ phenotype upon exposure to secondary messengers such as dibutyryl-cyclic-AMP and/or growth factors such as basic fibrillary growth factor. Continuous stimulation with these messengers resulted in terminal differentiation and consequent death upon withdrawal of the stimulus. These results provide information that could lead to detailed characterization of initiated, premalignant cells in the adult brain and to a better understanding of glial carcinogenesis.

Ablation of NF1 function in neurons induces abnormal development of cerebral cortex and reactive gliosis in the brain.

Neurofibromatosis type 1 (NF1) is a prevalent genetic disorder that affects growth properties of neural-crest-derived cell populations. In addition, approximately one-half of NF1 patients exhibit learning disabilities. To characterize NF1 function both in vitro and in vivo, we circumvent the embryonic lethality of NF1 null mouse embryos by generating a conditional mutation in the NF1 gene using Cre/loxP technology. Introduction of a Synapsin I promoter driven Cre transgenic mouse strain into the conditional NF1 background has ablated NF1 function in most differentiated neuronal populations. These mice have abnormal development of the cerebral cortex, which suggests that NF1 has an indispensable role in this aspect of CNS development. Furthermore, although they are tumor free, these mice display extensive astrogliosis in the absence of conspicuous neurodegeneration or microgliosis. These results indicate that NF1-deficient neurons are capable of inducing reactive astrogliosis via a non-cell autonomous mechanism.

Proliferative activity in craniopharyngiomas: clinicopathological correlations in adults and children.

BACKGROUND: Craniopharyngiomas are slow-growing, locally invasive intracranial tumors that can generate considerable morbidity, and recurrences are often difficult to manage. Because reliable morphologic criteria for accurately predicting the clinical outcome of these tumors are lacking, we evaluated the growth potential of craniopharyngiomas by measuring their proliferative activity based on MIB-1 immunostaining for the Ki-67 antigen, which is expressed during all phases of the cell cycle except G(0.) METHODS: Paraffin sections from 37 cases of craniopharyngiomas were immunostained with the monoclonal antibody MIB-1, and a labeling index was derived in each case from an the with the highest labeling. RESULTS: MIB-1 immunoreactivity was mainly confined to the peripheral palisaded epithelium of craniopharyngiomas. In adult craniopharyngiomas, MIB-1 labeling indices (MIB-LI) varied from 0.1% to 34.6% (mean 8.9%; SD 9. 8), and in pediatric tumors the indices ranged from 1.8% to 15.0% (mean 6.3%; SD 3.7). MIB-LI was not found to be an independent predictor of recurrence, although in all the pediatric cases that recurred, MIB-LI in the second specimen was greater. CONCLUSIONS: The actively proliferating compartment in craniopharyngiomas seems to be the peripheral palisaded epithelium. Low MIB-LI observed in the majority of tumors is in concordance with the slow growth and low-grade invasiveness associated with craniopharyngiomas. However, unlike other intracranial neoplasms, where Ki-67 labeling indices have been useful in predicting tumor behavior, a clear relationship could not be demonstrated between MIB-1 immunoreactivity, morphological features and clinical outcomes in adults or children with craniopharyngiomas.

Recurrent (nonfamilial) hemangioblastomas involving spinal nerve roots: case report.

OBJECTIVE AND IMPORTANCE: Spinal nerve root hemangioblastomas are rare and are reported mainly in patients with von Hippel-Lindau (VHL) syndrome. The pathogenesis of so-called nonfamilial lesions is virtually unknown. We discuss, mainly from a molecular perspective, a unique patient with sporadic, recurrent hemangioblastomas restricted to spinal nerve roots. CLINICAL PRESENTATION: A 53-year-old man who had had a surgically corrected lumbosacral meningomyelocele presented on at least three occasions during a 17-year period with multifocal capillary hemangioblastomas involving spinal nerve roots. On each occasion, tumors appeared on a different nerve root, with the majority located in the midcervical segments. The patient had no clinical features or family history of VHL syndrome. TECHNIQUE: To obtain a clearer understanding of the pathogenesis of this unusual case and its relationship to VHL syndrome, molecular analysis of the VHL gene was performed by use of complete sequence analysis and loss of heterozygosity studies on deoxyribonucleic acid derived from the patient's blood leukocytes and three separately resected hemangioblastomas. CONCLUSION: Germ-line molecular analysis performed on all three exons in the VHL gene coding region did not indicate that any mutations were present. Loss of heterozygosity analysis of deoxyribonucleic acid from the three hemangioblastoma resections showed normal heterozygosity in the 3p25-26 region. Complete VHL gene sequence analysis did not demonstrate a somatic mutation in the coding region of the VHL gene in any of the three tumors, thereby supporting the loss of heterozygosity data that a molecular event directly involving the VHL gene may not be the causative factor in their tumorigenesis.

Alpha-synuclein expression in central nervous system tumors showing neuronal or mixed neuronal/glial differentiation.

Alpha-synuclein (alpha-synuclein) is a member of a family of cytoplasmic proteins found predominantly and abundantly in the brain, and concentrated in pre-synaptic nerve terminals, near vesicles. We hypothesized that an antibody to alpha-synuclein could be a useful marker of neuronal differentiation in central nervous system (CNS) tumors. Twenty tumors known to have neuronal or mixed neuronal/glial differentiation ( 11 gangliogliomas, 2 anaplastic gangliogliomas, 5 gangliocytomas, and 2 ganglioneuroblastomas), 5 central neurocytomas, and 1 dysembryoplastic neuroepithelial tumor (DNET) were immunostained with a mouse monoclonal antibody raised against human alpha-synuclein. Intense cytoplasmic staining, in some instances extending into the perikarya, was seen in 6 of 11 gangliogliomas, 2 of 2 anaplastic gangliogliomas, and 2 of 2 ganglioneuroblastomas. Alpha-synuclein-positive cells were usually large in size, resembled dysmorphic neurons, and were variably immunoreactive for anti-neurofilament and/or anti-synaptophysin antibodies. In contrast, central neurocytomas, gangliocytomas, and the DNET were negative for cytoplasmic alpha-synuclein expression. Our findings indicate that alpha-synuclein is expressed within the neuronal component of mixed tumors of the CNS displaying more than 1 histophenotype, and/or showing different degrees of anaplasia. Based on currently available data, we conclude that cytoplasmic alpha-synuclein expression is a marker of maturing neurons in these tumors.

Mouse tumor model for neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterized by increased incidence of benign and malignant tumors of neural crest origin. Mutations that activate the protooncogene ras, such as loss of Nf1, cooperate with inactivating mutations at the p53 tumor suppressor gene during malignant transformation. One hundred percent of mice harboring null Nf1 and p53 alleles in cis synergize to develop soft tissue sarcomas between 3 and 7 months of age. These sarcomas exhibit loss of heterozygosity at both gene loci and express phenotypic traits characteristic of neural crest derivatives and human NF1 malignancies.