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The German Society of Neurosurgery (DGNC) was founded in Bonn in 1950 and saw itself as the all-German representation of neurosurgeons. The development of neurosurgery in divided Germany was different in each case as part of a system and was not unaffected by the confrontation between the two blocs (cold war), which also had a negative impact on the field of science. Thus, early on, restrictions on intra-German travel from the East made normal relations difficult. But travel restrictions also came from the West, where an Allied Travel Office in West Berlin decided whether an East German could enter a North Atlantic Treaty Organization (NATO) country. Nevertheless, it was possible that Georg Merrem from Leipzig took over the second chairmanship of the board of the DGNC of the election period from 1960 to 1962 and eight individual memberships of German Democratic Republic (GDR) neurosurgeons were still tolerated by the state side. The construction of the Berlin Wall on August 13, 1961 meant that these connections also collapsed. Merrem, at that time the only full professor of neurosurgery in the GDR, founded the “Association of Neurosurgeons in the GDR” in 1962 in agreement with the state authorities. With the foundation of a GDR neurosurgeons' society, the demarcation from the DGNC desired by the state was visibly accomplished. There were no official relations between the two neurosurgical societies. During the period of its existence until 1990, the entire work of the East German society was under the guidance and control of state institutions, which in turn derived their work from the guidelines of the party and the decisions of the council of ministers. Using the example of the congress activities of the first 5 years after the Wall was built, we show this dependence on state institutions. It extends from congress planning to reporting. With available figures of participating speakers from West Germany and other countries, it is demonstrated for the individual congresses in Leipzig, Magdeburg, and Erfurt that the German–German connection was continued despite all adverse circumstances. The presence of West German colleagues, who were not deterred from attending the congress even by the construction of the Berlin Wall, can be seen as a visible expression of an unbroken togetherness. However, already in 1967, the party and the council of ministers passed the resolution “On the organization of work in the field of science and culture of the GDR to West Germany as well as West Berlin.” This regulated membership, the associated travel, and the conditions for publications in West German journals. Among other things, this directive prohibited membership in scientific societies, including the DGNC, based in West Germany. The organization of its own congresses took on a special significance because a congress visit from East to West was regulated by the state and thus only possible in isolated cases.

Glioblastoma (GBM) is a poorly treatable disease due to the fast development of tumor recurrences and high resistance to chemo- and radiotherapy. To overcome the highly adaptive behavior of GBMs, especially multimodal therapeutic approaches also including natural adjuvants have been investigated. However, despite increased efficiency, some GBM cells are still able to survive these advanced treatment regimens. Given this, the present study evaluates representative chemoresistance mechanisms of surviving human GBM primary cells in a complex in vitro co-culture model upon sequential application of temozolomide (TMZ) combined with AT101, the R(-) enantiomer of the naturally occurring cottonseed-derived gossypol. Treatment with TMZ+AT101/AT101, although highly efficient, yielded a predominance of phosphatidylserine-positive GBM cells over time. Analysis of the intracellular effects revealed phosphorylation of AKT, mTOR, and GSK3ß, resulting in the induction of various pro-tumorigenic genes in surviving GBM cells. A Torin2-mediated mTOR inhibition combined with TMZ+AT101/AT101 partly counteracted the observed TMZ+AT101/AT101-associated effects. Interestingly, treatment with TMZ+AT101/AT101 concomitantly changed the amount and composition of extracellular vesicles released from surviving GBM cells. Taken together, our analyses revealed that even when chemotherapeutic agents with different effector mechanisms are combined, a variety of chemoresistance mechanisms of surviving GBM cells must be taken into account.

APLNR expression is upregulated in the infiltrating tumor zone in glioblastoma.

APLN co-expressed genes are enriched for angiogenesis in glioblastoma subtypes

Antiangiogenic therapy of glioblastoma (GBM) with bevacizumab, a VEGFA-blocking antibody, may accelerate tumor cell invasion and induce alternative angiogenic pathways. Here we investigate the roles of the proangiogenic apelin receptor APLNR and its cognate ligand apelin in VEGFA/VEGFR2 antiangiogenic therapy against distinct subtypes of GBM. In proneural GBM, apelin levels were downregulated by VEGFA or VEGFR2 blockade. A central role for apelin/APLNR in controlling GBM vascularization was corroborated in a serial implantation model of the angiogenic switch that occurs in human GBM. Apelin and APLNR are broadly expressed in human GBM, and knockdown or knockout of APLN in orthotopic models of proneural or classical GBM subtypes significantly reduced GBM vascularization compared with controls. However, reduction in apelin expression led to accelerated GBM cell invasion. Analysis of stereotactic GBM biopsies from patients as well as from in vitro and in vivo experiments revealed increased dissemination of APLNR-positive tumor cells when apelin levels were reduced. Application of apelin-F13A, a mutant APLNR ligand, blocked tumor angiogenesis and GBM cell invasion. Furthermore, cotargeting VEGFR2 and APLNR synergistically improved survival of mice bearing proneural GBM. In summary, we show that apelin/APLNR signaling controls GBM angiogenesis and invasion and that both pathologic features are blunted by apelin-F13A. We suggest that apelin-F13A can improve the efficiency and reduce the side effects of established antiangiogenic treatments for distinct GBM subtypes.Significance:Pharmacologic targeting of the APLNR acts synergistically with established antiangiogenic treatments in glioblastoma and blunts therapy resistance to current strategies for antiangiogenesis.See related commentary by Amoozgar et al., p. 2104

Supplementary Figure 1 from A1 Adenosine Receptors in Microglia Control Glioblastoma-Host Interaction

We report that experimental glioblastoma grow more vigorously in A1 adenosine receptor (A1AR)–deficient mice associated with a strong accumulation of microglial cells at and around the tumors. A1ARs were prominently expressed in microglia associated with tumor cells as revealed with immunocytochemistry but low in microglia in the unaffected brain tissue. The A1AR could also be detected on microglia from human glioblastoma resections. To study functional interactions between tumor and host cells, we studied glioblastoma growth in organotypical brain slice cultures. A1AR agonists suppressed tumor growth. When, however, microglial cells were depleted from the slices, the agonists even stimulated tumor growth. Thus, adenosine attenuates glioblastoma growth acting via A1AR in microglia. (Cancer Res 2006; 66(17): 8550-7)

In neurosurgery, an exact delineation of functional areas is of great interest to spare important regions to ensure the best possible outcome for the patient, i.e. maximum removal while maintaining the highest possible quality of life. Preoperative imaging is routinely performed, including the visualization of not only structural but also functional information. During surgery however, brain shift can occur, leading to an offset between the previously defined and the real position. Real-time imaging during the procedure is therefore desired to obtain this information while performing surgery. In this study 15 patients suffering from glioblastoma multiforme were included. These patients underwent structural and perfusion imaging using Arterial Spin Labeling during the procedure. The latter has been used for gathering information about tumor residual perfusion. However, special post-processing of this data allows for additional mapping of resting state networks and is intended to be used to gather deeper insights to aid the surgeon in planning the further procedure. The data of each patient could be successfully post-processed and used to map different resting state networks alongside the default mode network. Based on this study, it is feasible to use the information obtained from perfusion imaging to not only visualize vascular signal but also functional activation of resting state networks without acquiring any additional data besides the already available information. This may help guide the neurosurgeon in real time to adjust the surgical plan.

The cellular and molecular mechanisms that presumably underlie the progressive functional decline of the myelomeningocele (MMC) placode are not well understood. We previously identified key players in post-traumatic spinal cord injury cascades in human MMC tissues obtained during postnatal repair. In this study, we conducted experiments to further investigate these mediators in the prenatal time course under standardized conditions in a retinoic acid-induced MMC rat model. A retinoic acid MMC model was established using time-dated Sprague-Dawley rats, which were gavage-fed with all-trans retinoic acid (RA; 60 mg/kg) dissolved in olive oil at E10. Control animals received olive oil only. Fetuses from both groups were obtained at E16, E18, and E22. The spinal cords (SCs) of both groups were formalin-fixed or snap-frozen. Tissues were screened by real-time reverse transcription polymerase chain reaction for the expression of cytokines and chemokines known to play a role in the lesion cascades of the central nervous system after trauma. MMC placodes exhibited inflammatory cells and glial activation in the later gestational stages. At the messenger RNA (mRNA) level, interleukin-1 beta, tumor necrosis factor alpha, and tumor necrosis factor receptor type 1 exhibited significant induction at E22. interleukin-1 beta receptor type 1 mRNA was induced significantly at E16 and E22. Double labeling experiments confirmed the co-staining of these cytokines and their receptors with ionized calcium-binding adapter molecule 1 (i.e., inflammatory cells), vimentin, and nestin in different anatomical SC areas and neuronal nuclear protein in ventral horn neurons. C-X-C motif chemokine 12 mRNA was elevated in control and MMC animals at E16 compared with E18 and E22. C-X3-C motif ligand 1 mRNA was lower in MMC tissues than in control tissues on E16. The presented findings contribute to the concept that pathophysiological mechanisms, such as cytokine induction in the neuroplacode, in addition to the "first hit," promote secondary spinal cord injury with functional loss in the late fetal time course. Further, these mediators should be taken into consideration in the development of new therapeutic approaches for open spinal dysraphism.

Background The activating Natural killer group 2 member D (NKG2D) receptor is typically expressed on NK cells, CD8 T lymphocytes, γδ T cells and small subsets of CD4 T lymphocytes. During the course of an extensive flow cytometry phenotyping of immune cells in the peripheral blood of patients with glioblastoma multiforme (GBM) we noticed an unexpected expression of NKG2D receptor on granulocytes using the phycoerythrin (PE)-conjugated clone 149810 antibody. Methods Peripheral blood samples from 35 patients with GBM and 22 age-matched healthy control (HC) donors were analyzed using flow cytometry, imaging cytometry and real-time quantitative reverse transcription PCR to validate the observed expression of NKG2D receptor on myeloid cells. Results Reactivity with PE-149810 was mostly observed on granulocytes from GBM patients on dexamethasone treatment where it correlated with inferior survival rates. Surprisingly, such NKG2D expression on granulocytes was not observed using the allophycocyanin (APC)-conjugate of the same clone 149810 antibody or an indirect staining procedure with unconjugated clone 149810 antibody. Moreover, the PE-conjugate of a different anti-NKG2D clone (1D11) also did not stain granulocytes. Imaging cytometry indicated cell surface and intracellular localization of PE-149810 but not of PE-1D11 in granulocytes. Conclusion Our results uncover an erroneous and false positive reactivity of PE-labeled (but not of APC-labeled or unconjugated) anti-NKG2D antibody 149810 on granulocytes from dexamethasone-treated GBM patients and raise a note of caution for studies of NKG2D expression on non-lymphoid cells.

Introduction AT101, the R-(-)-enantiomer of the cottonseed-derived polyphenol gossypol, is a promising drug in glioblastoma multiforme (GBM) therapy due to its ability to trigger autophagic cell death but also to facilitate apoptosis in tumor cells. It does have some limitations such as poor solubility in water-based media and consequent low bioavailability, which affect its response rate during treatment. To overcome this drawback and to improve the anti-cancer potential of AT101, the use of cubosome-based formulation for AT101 drug delivery has been proposed. This is the first report on the use of cubosomes as AT101 drug carriers in GBM cells. Materials and methods Cubosomes loaded with AT101 were prepared from glyceryl monooleate (GMO) and the surfactant Pluronic F-127 using the top-down approach. The drug was introduced into the lipid prior to dispersion. Prepared formulations were then subjected to complex physicochemical and biological characterization. Results Formulations of AT101-loaded cubosomes were highly stable colloids with a high drug entrapment efficiency (97.7%) and a continuous, sustained drug release approaching 35% over 72 h. Using selective and sensitive NMR diffusometry, the drug was shown to be efficiently bound to the lipid-based cubosomes. In vitro imaging studies showed the high efficiency of cubosomal nanoparticles uptake into GBM cells, as well as their marked ability to penetrate into tumor spheroids. Treatment of GBM cells with the AT101-loaded cubosomes, but not with the free drug, induced cytoskeletal rearrangement and shortening of actin fibers. The prepared nanoparticles revealed stronger in vitro cytotoxic effects against GBM cells (A172 and LN229 cell lines), than against normal brain cells (SVGA and HMC3 cell lines). Conclusion The results indicate that GMO-AT101 cubosome formulations are a promising basic tool for alternative approaches to GBM treatment.

OBJECTIVERechargeable neurostimulators for deep brain stimulation have been available since 2008, promising longer battery life and fewer replacement surgeries compared to non-rechargeable systems. Long-term data on how recharging affects movement disorder patients are sparse. This is the first multicenter, patient-focused, industry-independent study on rechargeable neurostimulators.METHODSFour neurosurgical centers sent a questionnaire to all adult movement disorder patients with a rechargeable neurostimulator implanted at the time of the trial. The primary endpoint was the convenience of the recharging process rated on an ordinal scale from “very hard” (1) to “very easy” (5). Secondary endpoints were charge burden (time spent per week on recharging), user confidence, and complication rates. Endpoints were compared for several subgroups.RESULTSDatasets of 195 movement disorder patients (66.1% of sent questionnaires) with Parkinson’s disease (PD), tremor, or dystonia were returned and included in the analysis. Patients had a mean age of 61.3 years and the device was implanted for a mean of 40.3 months. The overall convenience of recharging was rated as “easy” (4). The mean charge burden was 122 min/wk and showed a positive correlation with duration of therapy; 93.8% of users felt confident recharging the device. The rate of surgical revisions was 4.1%, and the infection rate was 2.1%. Failed recharges occurred in 8.7% of patients, and 3.6% of patients experienced an interruption of therapy because of a failed recharge. Convenience ratings by PD patients were significantly worse than ratings by dystonia patients. Caregivers recharged the device for the patient in 12.3% of cases. Patients who switched from a non-rechargeable to a rechargeable neurostimulator found recharging to be significantly less convenient at a higher charge burden than did patients whose primary implant was rechargeable. Age did not have a significant impact on any endpoint.CONCLUSIONSOverall, patients with movement disorders rated recharging as easy, with low complication rates and acceptable charge burden.

Purpose Circumferential enhancement on MR vessel wall imaging has been proposed as a biomarker of a higher risk of rupture in intracranial aneurysms. Focal enhancement is frequently encountered in unruptured aneurysms, but its implication for risk stratification and patient management remains unclear. This study investigates the association of focal wall enhancement with hemodynamic and morphological risk factors and histologic markers of wall inflammation and degeneration. Methods Patients with an unruptured middle cerebral artery aneurysm who underwent 3D rotational angiography and 3T MR vessel wall imaging showing focal wall enhancement were included. Hemodynamic parameters were calculated based on flow simulations and compared between enhanced regions and the entire aneurysm surface. Morphological parameters were semiautomatically extracted and quantitatively associated with wall enhancement. Histological analysis included detection of vasa vasorum, CD34, and myeloperoxidase staining in a subset of patients. Results Twenty-two aneurysms were analyzed. Enhanced regions were significantly associated with lower AWSS, lower maxOSI, and increased LSA. In multivariate analysis, higher ellipticity index was an independent predictor of wall enhancement. Histologic signs of inflammation and degeneration and higher PHASES score were significantly associated with focal enhancement. Conclusion Focal wall enhancement is colocalized with hemodynamic factors that have been related to a higher rupture risk. It is correlated with morphological factors linked to rupture risk, higher PHASES score, and histologic markers of wall destabilization. The results support the hypothesis that focal enhancement could serve as a surrogate marker for aneurysm instability.

Glioblastoma multiforme (GBM) is a malignant brain tumor that evades therapy regimens. Since cellular dormancy is one strategy for surviving, and since chemokines determine the environmental conditions in which dormancy occurs, we investigated how chemokines affect temozolomide (TMZ)-promoted cellular dormancy entry and exit in GBM cells. TMZ administration over ten days promoted cellular dormancy entry, whereas discontinuing TMZ for a further 15 days resulted in resumption of proliferation. Co-administration of a chemokine cocktail containing CXCL12, CXCL16, and CX3CL1 resulted in both delayed entry and exit from cellular dormancy. A microarray-based transcriptome analysis in LN229 GBM cells revealed that cellular dormancy entry was characterized by an increased expression of CCL2 and SAA2, while THSD4, FSTL3, and VEGFC were upregulated during dormancy exit. Co-stimulation with the chemokine cocktail reduced upregulation of identified genes. After verifying the appearance of identified genes in human GBM primary cultures and ex vivo samples, we clarified whether each chemokine alone impacts cellular dormancy mechanisms using specific antagonists and selective CRISPR/Cas9 clones. While expression of CCL2 and SAA2 in LN229 cells was altered by the CXCL12-CXCR4-CXCR7 axis, CXCL16 and CX3CL1 contributed to reduced upregulation of THSD4 and, to a weaker extent, of VEGFC. The influence on FSTL3 expression depended on the entire chemokine cocktail. Effects of chemokines on dormancy entry and exit-associated genes were detectable in human GBM primary cells, too, even if in a more complex, cell-specific manner. Thus, chemokines play a significant role in the regulation of TMZ-promoted cellular dormancy in GBMs.

Purpose Age and etiology play a crucial role in success of endoscopic third ventriculostomy (ETV) as a treatment of obstructive hydrocephalus. Outcome is worse in infants, and controversies still exist whether ETV is superior to shunt placement. We retrospectively analyzed 70 patients below 2 years from 4 different centers treated with ETV and assessed success. Methods Children Results We collected 70 patients. ETV success rate was 41.4%. The highest rate was in tumor-related hydrocephalus and fourth ventricle outlet obstruction (62.5%, 60%) and the lowest rate was in Chiari-type II and following infection (16.7%, 0%). The below 3 months age group showed relatively lower success rate (33.3%) in comparison to older groups which showed similar results (46.4%, 46.6%). Statistically, a previous VP shunt was a predictor for failure (p value Conclusion Factors suggesting a high possibility of failure were age

Current treatment strategies for glioblastoma (GBM) including surgical resection and adjuvant radio/chemotherapy result in a limited progression-free survival time of patients due to rapidly occurring tumor recurrences. The urgent need for more effective treatments has led to the development of different approaches for localized drug delivery systems (DDSs) offering the advantages of reduced systemic side effects. A promising candidate for the treatment of GBMs is AT101, the R-(-)-enantiomer of gossypol due to its ability to induce apoptosis or trigger autophagic cell death in tumor cells. Here, we present an alginate-based drug-releasing mesh ladened with AT101-loaded PLGA microspheres (AT101-GlioMesh). The AT101-loaded PLGA microspheres were fabricated using an oil-in-water emulsion solvent evaporation method obtaining a high encapsulation efficiency. The drug-loaded microspheres enabled the release of AT101 over several days at the tumor site. The cytotoxic effect of the AT101-loaded mesh was evaluated using two different GBM cell lines. Strikingly, encapsulation of AT101 in PLGA-microparticles and subsequent embedding in GlioMesh resulted in a sustained delivery and more efficient cytotoxic effect of AT101 on both GBM cell lines. Thus, such a DDS holds promise for GBM therapy likely by preventing the development of tumor recurrences.

The intraoperative diagnosis of brain tumors remains a clinical challenge despite recent technological advances. The current clinical practice differentiates non-surgical brain tumors from those preferably treated with cytoreductive surgery employing intraoperative frozen section diagnostics. A detailed molecular diagnosis required for this classification task within the timeframe of a routine neurosurgical procedure is currently unavailable. We have analyzed a clinical cohort of several brain tumor entities using Nanopore long-read sequencing on two Oxford Nanopore Technologies sequencing platforms (MinION, PromethION). Since currently available molecular cancer classifiers such as the DKFZ methylation profiling classifier cannot be readily adapted to real-time sequencing analysis, we implemented a novel algorithm (MethyLYZR) to predict the underlying cancer type. Publicly available Illumina Infinium array data were used to train the classifier to distinguish 91 brain tumor classes. For validation of classification accuracy, we conducted a comprehensive validation strategy. Both nanopore platforms could sequence more than 5,000 pre-selected CpG within less than 20 minutes for most of our samples. When combining an optimized library preparation protocol with the time used for sequencing the minimal number of CpGs needed for classification, we saw sample-to-answer times of less than 1 hour – in many cases within 45 minutes - from receiving a fresh biopsy to a robust cancer type prediction. Comparing actual and predicted diagnoses resulted in a favorable error rate, indicating potentially highly clinical validity. Our real-time based molecular diagnostic algorithm enables, in most cases, a reliable diagnostic call within the timeframe of a typical neuro-oncological surgery. MethyLYZR as a predictive tool may allow us to adjust the surgical strategy and deliver the prognosis to our patients right after surgery, thus allowing for as-of-yet unexplored opportunities for the intraoperative application of individualized therapeutic modalities.

Glioblastoma multiforme (GBM) is a poorly curable disease due to its profound chemoresistance. Despite recent advances in surgery, radiotherapy and chemotherapy, the efficient treatment of GBMs is still a clinical challenge. Beside others, AT101, the R-(−) enantiomer of gossypol, and demethoxycurcumin (DMC), a curcumin-related demethoxy compound derived from Curcuma longa, were considered as possible alternative drugs for GBM therapy. Using different human primary GBM cell cultures in a long-term stimulation in vitro model, the cytotoxic and anti-proliferative effects of single and combined treatment with 5 µM AT101 and 5 µM or 10 µM DMC were investigated. Furthermore, western blots on pAkt and pp44/42 as well as JC-1 staining and real-time RT-PCR were performed to understand the influence of the treatment at the molecular and gene level. Due to enhanced anti-proliferative effects, we showed that combined therapy with both drugs was superior to a single treatment with AT101 or DMC. Here, by determination of the combination index, a synergism of the combined drugs was detectable. Phosphorylation and thereby activation of the kinases p44/42 and Akt, which are involved in proliferation and survival processes, were inhibited, the mitochondrial membrane potential of the GBM cells was altered, and genes involved in dormancy-associated processes were regulated by the combined treatment strategy. Combined treatment with different drugs might be an option to efficiently overcome chemoresistance of GBM cells in a long-term treatment strategy.

Wall enhancement of intracranial aneurysms in vessel wall magnetic resonance imaging (MRI) has been linked to aneurysm progression. The clinical significance of aneurysm enhancement after embolization has not yet been investigated. The goal of this study was to identify factors associated with aneurysm wall enhancement and reperfusion after embolization. Patients who underwent treatment of intracranial aneurysms with coils or the Woven Endobridge (WEB) and follow-up MR vessel wall imaging were included. Enhancement of the treated aneurysms was separately recorded for the following locations: a) wall at the neck, b) wall at the dome, and c) in the aneurysmal cavity. Reperfusion was determined on follow-up digital subtraction angiography (DSA) and MR time of flight (TOF) angiography. In this study 48 patients with 53 aneurysms were included. Wall enhancement at the neck and the dome of the aneurysm was significantly associated with time between embolization and follow-up MRI under 6 months. Enhancement inside the aneurysmal cavity was significantly associated with a follow-up time longer than 6 months, and with stable aneurysms without reperfusion. Wall enhancement is a regular feature in intracranial aneurysms after embolization and decreases over time. Enhancement inside the aneurysmal cavity is associated with a stable state and could possibly serve as an imaging marker of completed aneurysm healing.

BACKGROUND In diffuse WHO grade II gliomas (LGG), the extent of resection (EOR) required to achieve significant survival benefits remains elusive. OBJECTIVE To evaluate the association of residual volume (RV) and EOR with progression-free survival (PFS) or overall survival (OS) in LGG in a retrospective, multicenter series by the German study group of intraoperative MRI (GeSGIM). METHODS Consecutive cases were retrospectively assessed from 5 centers. Tumors were volumetrically quantified before and after surgery, and clinical data were analyzed, including IDH mutations and neurologic deficits. Kaplan-Meier estimates, accelerated failure time models (AFT), and multivariate Cox regression models were calculated to identify determinants of survival. RESULTS A total of 140 cases were analyzed. Gross total resection (GTR) was associated with significantly longer PFS compared to any incomplete resection (P = .009). A significant survival disadvantage was evident even for small (>0-5 ml) residuals and increased for moderate (>5-20 ml) and large remnants (>20 ml) P = .001). Accordingly, PFS increased continuously for 20% incremental steps of EOR (P

Objective To examine the results of an anular closure device for prevention of lumbar disc reherniation in daily routine practice. Methods Fifty patients with large anular defects were treated with limited discectomy and a bone‐anchored anular closure device. The device physically occludes the defect in the anulus fibrosus and is intended for prevention of lumbar disc reherniation. Pain scores on a visual analogue scale, back function on the Oswestry Disability Index, and neurological status were noted. Symptomatic reherniation and reoperation rates were assessed at each follow‐up. Surgical findings and complications, device‐related and/or procedure‐related, were recorded. Follow‐up was 6, 12, 26, and 52 weeks. Results Mean anular defect height/width was 4.6 mm/10.1 mm. The overall symptomatic reherniation and reoperation rate was 2%. During the 1‐year follow‐up period, mean back pain decreased from 43 to 8 (P < 0.001), leg pain decreased from 71 to 4 (P < 0.001), and the Oswestry Disability Index decreased from 46 to 5 (P < 0.001). Among 15 patients with preoperative neurological deficits, improvements in neurological function were noted in 14 (93%). There were no serious device‐related complications. Conclusions The presented study shows promising early results in using the anular closure device. The procedure is safe with significantly fewer reherniations than for patients with large anular defects without anular closure. Further studies with longer follow‐up periods are warranted to prove these findings for long‐term outcomes.

Transcriptomic screens of brain tumor (glioblastoma; GBM) parenchymal cells indicated tumor supporting traits of the GBM microenvironment, but largely excluded mitochondrially enriched gene-sets. Here, we show that a mitochondrial transcript of GBM parenchymal cells contributes to therapy resistance. We inspected the non-coding transcriptome of human GBM associated myeloid cells (GAM) and observed an upregulation of the mitochondrial ribosomal subunit MT-RNR2, which contains an open reading frame for the signaling peptide humanin. Immunohistology disclosed that humanin was preponderant in GAM. In vitro assays with a range of human stem-like GBM cells (GSCs) revealed that nanomolar concentrations of humanin can drive tumor cell expansion and chemoresistance to temozolomide. A series of genetic, pharmacological and Western blotting experiments showed that extracellular humanin increased GSC viability via stimulation of the GP130/IL6ST receptor and MAPK (Erk) activation. Humanin responsiveness was subject to inter-individual heterogeneity and predominated in GSC with high expression levels of the IL6ST subunit. Mechanistically, humanin promoted the ATR-dependent DNA-repair machinery in GSCs via induction of the DNA-clamp component HUS1. A slice culture model containing human microglia and GSCs confirmed these observations. Humanin is absent from the mouse brain. Exogenous delivery of humanin into orthotopic GBM mouse models or over-expression specifically of a secreted humanin variant recapitulated the in vitro findings. Blockade of the trimeric interleukin receptor with the brain permeant, FDA-approved drug bazedoxifene blocked humanin-mediated chemoresistance in vitro and in vivo. Overall, we identified a clinically applicable compound together with a predictive marker to prevent chemoresistance in a human-specific GBM model.

Factors released from glioma-associated microglia/macrophages (GAMs) play a crucial role in glioblastoma multiforme (GBM) progression. Here, we study the importance of CCL18, a cytokine expressed in human but not in rodent GAMs, as a modulator of glioma growth. Since CCL18 signaling could not be studied in classical mouse glioma models, we developed an approach by transplanting induced pluripotent stem cell-derived human microglia and human glioma cells into mouse brain slices depleted of their intrinsic microglia. We observe that CCL18 promotes glioma cell growth and invasion. Chemokine (C-C motif) receptor 8 (CCR8) is identified as a functional receptor for CCL18 on glioma cells, and ACP5 (acid phosphatase 5) is revealed as an important part of the downstream signaling cascade for mediating glioma growth. We conclude, based on the results from an in vitro, ex vivo humanized glioma model and an in vivo GBM model that microglia/macrophage-derived CCL18 promotes glioma growth.

BACKGROUND Glioblastoma multiforme is a highly malignant brain tumor with a devastating prognosis. Resection followed by radio-chemotherapy leads to an overall survival of only 15 months. Up to 40% of the tumor mass consist of tumor-associated microglia and macrophages (TAMs). These cells were shown to promote tumor growth and invasiveness in many murine glioma models. The interaction between TAMs and tumor cells is crucial for tumor progression and includes several known pathways. Still, murine glioma models only partially mirror the human tumor microenvironment. Several known genes, which are highly upregulated in human glioma and TAMs are only expressed in human tissue and not in mice. To further investigate some of these genes, we aimed at establishing a humanized ex-vivo brain slice model, in which human TAMs and human glioma cells can be studied in a standardized manner. MATERIAL AND METHODS We used 250 micrometer thick murine brain slices, which were depleted of intrinsic microglia by applying clodoronated liposomes. Next, we inoculated human glioma cells (originating from the cell lines mCherryU87, mCherryU251MG, mCherryLN229 and several patient derived cells lines) with or without human microglia derived from induced pluripotent stem cells (iPSCs). Slices were cultivated for 7 to 14 days. Next, we performed a detailed analysis of microglia morphology (sphericity, cell body volume, process length and branching pattern) and tumor volume. RESULTS Clodronation efficacy was high, depending on duration of treatment and length of cultivation. iPSCs and tumor cells integrated into the slice very well. The presence of tumor cells led to an increased sphericity of iPSC-dervied microglia and to an increased cell body volume. Branching pattern and process length did not differ between both conditions. Tumor volume was significantly larger when iPSC-derived microglia were present. This was found in various glioma cells lines and also in patient derived cells. CONCLUSION The newly established humanized ex-vivo brain slice system was shown to be feasible. The method successfully allows to study the interaction between human TAMs and tumor cells. Microglia foster tumor growth not only in murine glioma models, but also in a human paradigm. The humanized ex-vivo brain slice model therefore is the optimal basis to study the role human-specific genes in TAM-glioma interaction.

Glioblastoma (GBM) is a barely treatable disease due to its profound chemoresistance. A distinct inter- and intratumoral heterogeneity reflected by specialized microenvironmental niches and different tumor cell subpopulations allows GBMs to evade therapy regimens. Thus, there is an urgent need to develop alternative treatment strategies. A promising candidate for the treatment of GBMs is AT101, the R(-) enantiomer of gossypol. The present study evaluates the effects of AT101, alone or in combination with temozolomide (TMZ), in a microenvironmental glioma stem cell niche model of two GBM cell lines (U251MG and U87MG). AT101 was found to induce strong cytotoxic effects on U251MG and U87MG stem-like cells in comparison to the respective native cells. Moreover, a higher sensitivity against treatment with AT101 was observed upon incubation of native cells with a stem-like cell-conditioned medium. This higher sensitivity was reflected by a specific inhibitory influence on the p-p42/44 signaling pathway. Further, the expression of CXCR7 and the interleukin-6 receptor was significantly regulated upon these stimulatory conditions. Since tumor stem-like cells are known to mediate the development of tumor recurrences and were observed to strongly respond to the AT101 treatment, this might represent a promising approach to prevent the development of GBM recurrences.

Deep brain stimulation (DBS) seems to modulate inflammatory processes. Whether this modulation leads to an induction or suppression of inflammatory mediators is still controversially discussed. Most studies of the influence of electrical stimulation on inflammation were conducted in rodent models with direct current stimulation and/or long impulses, both of which differ from the pattern in DBS. This makes comparisons with the clinical condition difficult. We established an in-vitro model that simulated clinical stimulation patterns to investigate the influence of electrical stimulation on proliferation and survival of human astroglial cells, microglia, and differentiated neurons. We also examined its influence on the expression of the inflammatory mediators C-X-C motif chemokine (CXCL)12, CXCL16, CC-chemokin-ligand-2 (CCL)2, CCL20, and interleukin (IL)-1β and IL-6 by these cells using quantitative polymerase chain reaction. In addition, protein expression was assessed by immunofluorescence double staining. In our model, electrical stimulation did not affect proliferation or survival of the examined cell lines. There was a significant upregulation of CXCL12 in the astrocyte cell line SVGA, and of IL-1β in differentiated SH-SY5Y neuronal cells at both messenger RNA and protein levels. Our model allowed a valid examination of chemokines and cytokines associated with inflammation in human brain cells. With it, we detected the induction of inflammatory mediators by electrical stimulation in astrocytes and neurons.

Ingredients of brown seaweed like fucoidans are often described for their beneficial biological effects, that might be interesting for a medical application. In this study, we tested an extract from Dictyosiphon foeniculaceus (DF) to evaluate the effects in glioblastoma and uveal melanoma, looking for a possible anti-cancer treatment. We investigated toxicity, VEGF (vascular endothelial growth factor) secretion and gene expression of tumor and non-tumor cells. SVGA (human fetal astrocytes), the human RPE (retinal pigment epithelium) cell line ARPE-19, the tumor cell line OMM-1 (human uveal melanoma), and two different human primary glioblastoma cultures (116-14 and 118-14) were used. Tests for cell viability were conducted with MTS-Assay (3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium), and the proliferation rate was determined with cell counting. VEGF secretion was assessed with ELISA (enzyme-linked immunosorbent assay). The gene expression of VEGF receptor 1 (VEGFR1), VEGF receptor 2 (VEGFR2) and VEGF-A was determined with real-time qPCR (quantitative polymerase chain reaction). DF lowered the cell viability of OMM-1. Proliferation rates of ARPE-19 and OMM-1 were decreased. The VEGF secretion was inhibited in ARPE-19 and OMM-1, whereas it was increased in SVGA and 116-14. The expression of VEGFR1 was absent and not influenced in OMM-1 and ARPE-19. VEGFR2 expression was lowered in 116-14 after 24 h, whereas VEGF-A was increased in 118-14 after 72 h. The extract lowered cell viability slightly and was anti-proliferative depending on the cell type investigated. VEGF was heterogeneously affected. The results in glioblastoma were not promising, but the anti-tumor properties in OMM-1 could make them interesting for further research concerning cancer diseases in the human eye.

Background The transcription factor NF-κB drives neoplastic progression of many cancers including primary brain tumors (glioblastoma [GBM]). Precise therapeutic modulation of NF-κB activity can suppress central oncogenic signaling pathways in GBM, but clinically applicable compounds to achieve this goal have remained elusive. Methods In a pharmacogenomics study with a panel of transgenic glioma cells, we observed that NF-κB can be converted into a tumor suppressor by the non-psychotropic cannabinoid cannabidiol (CBD). Subsequently, we investigated the anti-tumor effects of CBD, which is used as an anticonvulsive drug (Epidiolex) in pediatric neurology, in a larger set of human primary GBM stem-like cells (hGSC). For this study, we performed pharmacological assays, gene expression profiling, biochemical, and cell-biological experiments. We validated our findings using orthotopic in vivo models and bioinformatics analysis of human GBM datasets. Results We found that CBD promotes DNA binding of the NF-κB subunit RELA and simultaneously prevents RELA phosphorylation on serine-311, a key residue that permits genetic transactivation. Strikingly, sustained DNA binding by RELA-lacking phospho-serine 311 was found to mediate hGSC cytotoxicity. Widespread sensitivity to CBD was observed in a cohort of hGSC defined by low levels of reactive oxygen species (ROS), while high ROS content in other tumors blocked CBD-induced hGSC death. Consequently, ROS levels served as a predictive biomarker for CBD-sensitive tumors. Conclusions This evidence demonstrates how a clinically approved drug can convert NF-κB into a tumor suppressor and suggests a promising repurposing option for GBM therapy.

Objective: Infections are feared complications following deep brain stimulation in 1.9 to 17.6% of cases. These infections can necessitate the removal of implants, which carries the risk of life-threatening withdrawal syndromes, especially in patients suffering from Parkinson’s disease. In this report, we describe our procedure of removing an infected implanted pulse generator (IPG) and cables with contralateral replacement in the same session. Methods: We retrospectively analysed all patients with transpositions of an IPG and cables between 2017 and 2020 in a single-centre, university hospital setting. Medical records of all patients undergoing this particular surgical procedure were systematically reviewed. The shortest follow-up time was 12 months. Results: Between 2017 and 2020, we had 6 patients with a high risk of withdrawal syndrome in whom an infected IPG with cables was removed and replaced on the opposite side in the same session. There were postoperative complications in 2 patients: in one, the generator had to be re-affixed, and in the second, a skin transplant was required over one electrode because of skin necrosis. No case of invasive infection was seen, and the stimulation therapy was not interrupted. Conclusion: One-session removal of an IPG and cables with contralateral replacement seems to be an effective therapy for patients at high risk of withdrawal syndrome.

(1) Background: Metabolic reprogramming has been postulated to be one of the hallmarks of cancer, thus representing a promising therapeutic target also in glioblastoma multiforme (GBM). Hypoxic tumor cells produce lactate, and monocarboxylate transporters (MCTs) play an important role in its distribution, (2) Methods: We examined the distribution of lactate by multi voxel magnetic resonance spectroscopic imaging and ELISA in glioblastoma multiforme (GBM) patients. In addition, we investigated the expression and cellular localization of MCT1, MCT4, and of several markers connected to tumor progression by quantitative PCR and immunofluorescence double-staining in human GBM ex vivo tissues, (3) Results: The highest lactate concentration was found at the center of the vital parts of the tumor. Three main GBM groups could be distinguished according to their regional gene expression differences of the investigated genes. MCT1 and MCT4 were found on cells undergoing epithelial to mesenchymal transition and on tumor stem-like cells. GBM cells revealing an expression of cellular dormancy markers, showed positive staining for MCT4, (4) Conclusion: Our findings indicate the existence of individual differences in the regional distribution of MCT1 and MCT4 and suggest that both transporters have distinct connections to GBM progression processes, which could contribute to the drug resistance of MCT-inhibitors.

Introduction AT101, the R-(-)-enantiomer of the cottonseed-derived polyphenol gossypol, is a promising drug in glioblastoma multiforme (GBM) therapy due to its ability to trigger autophagic cell death but also to facilitate apoptosis in tumor cells. It does have some limitations such as poor solubility in water-based media and consequent low bioavailability, which affect its response rate during treatment. To overcome this drawback and to improve the anti-cancer potential of AT101, the use of cubosome-based formulation for AT101 drug delivery has been proposed. This is the first report on the use of cubosomes as AT101 drug carriers in GBM cells. Materials and Methods Cubosomes loaded with AT101 were prepared from glyceryl monooleate (GMO) and the surfactant Pluronic F-127 using the top–down approach. The drug was introduced into the lipid prior to dispersion. Prepared formulations were then subjected to complex physicochemical and biological characterization. Results Formulations of AT101-loaded cubosomes were highly stable colloids with a high drug entrapment efficiency (97.7%) and a continuous, sustained drug release approaching 35% over 72 h. Using selective and sensitive NMR diffusometry, the drug was shown to be efficiently bound to the lipid-based cubosomes. In vitro imaging studies showed the high efficiency of cubosomal nanoparticles uptake into GBM cells, as well as their marked ability to penetrate into tumor spheroids. Treatment of GBM cells with the AT101-loaded cubosomes, but not with the free drug, induced cytoskeletal rearrangement and shortening of actin fibers. The prepared nanoparticles revealed stronger in vitro cytotoxic effects against GBM cells (A172 and LN229 cell lines), than against normal brain cells (SVGA and HMC3 cell lines). Conclusion The results indicate that GMO-AT101 cubosome formulations are a promising basic tool for alternative approaches to GBM treatment.

Malignant gliomas are primary brain tumors with poor prognoses. These tumors are infiltrated by brain intrinsic microglia and peripheral monocytes which promote glioma cell invasion. In our previous studies, we discovered that the activation of Toll-like receptor 2 (TLR2) on microglia/brain macrophages converts them into a protumorigenic phenotype through the induction of matrix metalloproteinases (MMP) 9 and 14. In the present study, we used in vitro and in situ microglia-glioma interaction experimental models to test the impact of a novel inhibitor of TLR 2, ortho vanillin (O-Vanillin) to block TLR2 mediated microglia protumorigenic phenotype. We demonstrate that O-Vanillin inhibits the TLR2 mediated upregulation of MMP 9, MMP 14, IL 6 and iNOS expression. Similarly, the glioma supernatant induced MMP 9 and MMP 14 expression in murine and human microglia is abrogated by O-Vanillin treatment. O-Vanillin is not toxic for microglia, astrocytes or oligodendrocytes. Glioma growth in murine brain slice cultures is significantly reduced after treatment with O-Vanillin, and this reduced glioma growth depends on the presence of microglia. In addition, we also found that O-Vanillin inhibited the glioma induced proliferation of murine primary microglia. In summary, O-Vanillin attenuates the pro-tumorigenic phenotype of microglia/brain macrophages and thus qualifies as a candidate for glioma therapy.

Lumbosacral lipomas (LSLs), one form of closed spinal dysraphism, are congenital disorders of the terminal spinal cord (SC). Delayed neurologic deterioration often occurs in the subsequent developmental course of the patient. Identifying the cellular and molecular factors underlying the progressive damage to neural structures is a prerequisite for developing treatment strategies for LSLs.Nine LSL specimens obtained from the SC/lipoma interface during surgical resection were examined. Normal SC tissue served as a control. Clinical characteristics were obtained, and spinal magnetic resonance imaging was re-evaluated. Cellular marker profiles were established. Immunoreactivity (IR) of hypoxia-inducible factor 1α (HIF-1α/-2α), erythropoietin (Epo)/erythropoietin receptor (EpoR), interleukin-1β (IL-1β)/IL-1R1, and tumor necrosis factor α/tumor necrosis factor receptor type 1 were analyzed qualitatively and semiquantitatively by densitometry. Colabeling with cellular markers was determined by multifluorescence labeling. Cytokines were further analyzed by real-time reverse transcription polymerase chain reaction.LSL specimens showed significant gliosis. HIF-1α/HIF-2α-IR and Epo/Epo-IR were found at significantly higher levels in the LSL specimens, as were IL-1β-/IL-1β receptor type 1 (IL1-R1) and tumor necrosis factor α/tumor necrosis factor receptor type 1 (P0.001), than were the controls. At the messenger RNA level, cytokines appeared partially induced. Double immunofluorescence labeling confirmed the costaining of these factors with inflammatory and glial markers.The expression of hypoxia-related and inflammatory mediators was shown for the first time in LSL specimens. These factors might play a role in multifactorial secondary lesion cascades underlying further damage to the neural placode in closed dysraphism.

In murine experimental glioma models, TLR3 or TLR9 activation of microglial/macrophages has been shown to impair glioma growth, which could, however, not been verified in recent clinical trials. We therefore tested whether combined TLR3 and TLR9 activation of microglia/macrophages would have a synergistic effect. Indeed, combined TLR3/TLR9 activation augmented the suppression of glioma growth in organotypic brain slices from male mice in a microglia-dependent fashion, and this synergistic suppression depended on interferon β release and phagocytic tumor clearance. Combined TLR3/TLR9 stimulation also augmented several functional features of microglia, such as the release of proinflammatory factors, motility, and phagocytosis activity. TLR3/TLR9 stimulation combined with CD47 blockade further augmented glioma clearance. Finally, we confirmed that the coactivation of TLR3/TLR9 also augments the impairment of glioma growth in vivo. Our results show that combined activation of TLR3/TLR9 in microglia/macrophages results in a more efficient glioma suppression, which may provide a potential strategy for glioma treatment. SIGNIFICANCE STATEMENT Glioma-associated microglia/macrophages (GAMs) are the predominant immune cells in glioma growth and are recently considered as antitumor targets. TLRs are involved in glioma growth, but the TLR3 or TLR9 ligands were not successful in clinical trials in treating glioma. We therefore combined TLR3 and TLR9 activation of GAMs, resulting in a strong synergistic effect of tumor clearance in vitro, ex vivo, and in vivo. Mechanisms of this GAM-glioma interaction involve IFNβ signaling and increased tumor clearance by GAMs. Interfering with CD47 signaling had an additional impact on tumor clearance. We propose that these signaling pathways could be exploited as anti-glioma targets.

The literature on histopathological and molecular changes that might underlie secondary tethered cord syndrome (TCS) after myelomeningocele (MMC) repair surgeries remains sparse. To address this problem, we analyzed specimens, which were obtained during untethering surgeries of patients who had a history of MMC repair surgery after birth. Specimens of 12 patients were analyzed in this study. Clinical characteristics were obtained retrospectively including pre-operative neurological and bowel/bladder-function, contractures and spasticity of lower extremities, leg and back pain, syringomyelia, and conus position on spinal MRI. Cellular marker expression profiles were established. Further, immunoreactivities (IR) of IL-1s/IL-1R1, TNF-α/TNF-R1, and HIF-1α/-2α were analyzed qualitatively and semi-quantitatively by densitometry. Co-labeling with cellular markers was determined by multi-fluorescence-labeling. Cytokines were further analyzed on mRNA level. Immunostaining for cleaved PARP and TUNEL was performed to detect apoptotic cells. Astrocytosis, appearance of monocytes, activated microglia, and apoptotic cells in TCS specimens were one substantial finding of these studies. Besides neurons, these cells co-stained with IL-1s and TNF-α and their receptors, which were found on significantly elevated IR-level and partially mRNA-level in TCS specimens. Staining for HIF-1α/-2α confirmed induction of hypoxia-related factors in TCS specimens that were co-labeled with IL-1s. Further, hints for apoptotic cell death became evident by TUNEL and PARP-positive cells in TCS neuroepithelia. Our studies identified pro-inflammatory and pro-apoptotic mediators that, besides mechanical damaging and along with hypoxia, might promote TCS development. Besides optimizing surgical techniques, these factors should also be taken into account when searching for further options to improve TCS treatment.