Analysis of tumor microenvironment composition in vestibular schwannomas: insights into NF2-associated and sporadic variations and their clinical correlations.

Objective: Vestibular schwannomas (VS), benign tumors stemming from the eighth cranial nerve's Schwann cells, are associated with Merlin gene mutations, inflammation, and the tumor microenvironment (TME), influencing tumor initiation, maintenance, and potential neural dysfunction. Understanding TME composition holds promise for systemic therapeutic interventions, particularly for NF2-related schwannomatosis. Methodology: A retrospective analysis of paraffin-embedded tissue from 40 patients (2013-2020), evenly divided by neurofibromatosis type 2 status, with further stratification based on magnetic resonance imaging (MRI) progression and hearing function. Immunohistochemistry assessed TME components, including T-cell markers (CD4, CD8, CD25), NK cells (CD7), and macrophages (CD14, CD68, CD163, CCR2). Fiji software facilitated image analysis. Results: T-cell markers (CD4, CD8, CD7) exhibited low expression in VS, with no significant NF2-associated vs. sporadic distinctions. Macrophage-related markers (CD14, CD68, CD163, CCR2) showed significantly higher expression (CD14: p = 0.0187, CD68: p < 0.0001, CD163: p = 0.0006, CCR2: p < 0.0001). CCR2 and CD163 significantly differed between NF2-associated and sporadic VS. iNOS, an M1-macrophage marker, was downregulated. CD25, a regulatory T-cell marker, correlated significantly with tumor growth dynamics (p = 0.016). Discussion: Immune cells, notably monocytes and macrophages, crucially contribute to VS pathogenesis in both NF2-associated and sporadic cases. Significant differences in CCR2 and CD163 expression suggest distinct immune responses. Regulatory T-cells may serve as growth dynamic markers. These findings highlight immune cells as potential biomarkers and therapeutic targets for managing VS.

Development of a vestibular schwannoma tumor slice model for pharmacological testing.

BACKGROUND: Our goal was to develop a 3D tumor slice model, replicating the individual tumor microenvironment and for individual pharmaceutical testing in vestibular schwannomas with and without relation to NF2. METHODS: Tissue samples from 16 VS patients (14 sporadic, 2 NF2-related) were prospectively analyzed. Slices of 350 µm thickness were cultured in vitro, and the 3D tumor slice model underwent thorough evaluation for culturing time, microenvironment characteristics, morphology, apoptosis, and proliferation rates. Common drugs - Lapatinib (10 µM), Nilotinib (20 µM), and Bevacizumab (10 µg/ml) - known for their responses in VS were used for treatment. Treatment responses were assessed using CC3 as an apoptosis marker and Ki67 as a proliferation marker. Standard 2D cell culture models of the same tumors served as controls. RESULTS: The 3D tumor slice model accurately mimicked VS ex vivo, maintaining stability for three months. Cell count within the model was approximately tenfold higher than in standard cell culture, and the tumor microenvironment remained stable for 46 days. Pharmacological testing was feasible for up to three weeks, revealing interindividual differences in treatment response to Lapatinib and intraindividual variability in response to Lapatinib and Nilotinib. The observed effects were less pronounced in tumor slices than in standard cell culture, indicating the model's proximity to in vivo tumor biology and enhanced realism. Bevacizumab had limited impact in both models. CONCLUSION: This study introduces a 3D tumor slice model for sporadic and NF2-related VS, demonstrating stability for up to 3 months, replication of the schwannoma microenvironment, and utility for individualized pharmacological testing.

Cultivating Ex Vivo Patient-Derived Glioma Organoids Using a Tissue Chopper.

Glioblastoma, IDH-wild type, CNS WHO grade 4 (GBM) is a primary brain tumor associated with poor patient survival despite aggressive treatment. Developing realistic ex vivo models remain challenging. Patient-derived 3-dimensional organoid (PDO) models offer innovative platforms that capture the phenotypic and molecular heterogeneity of GBM, while preserving key characteristics of the original tumors. However, manual dissection for PDO generation is time-consuming, expensive and can result in a number of irregular and unevenly sized PDOs. This study presents an innovative method for PDO production using an automated tissue chopper. Tumor samples from four GBM and one astrocytoma, IDH-mutant, CNS WHO grade 2 patients were processed manually as well as using the tissue chopper. In the manual approach, the tumor material was dissected using scalpels under microscopic control, while the tissue chopper was employed at three different angles. Following culture on an orbital shaker at 37 °C, morphological changes were evaluated using bright field microscopy, while proliferation (Ki67) and apoptosis (CC3) were assessed by immunofluorescence after 6 weeks. The tissue chopper method reduced almost 70% of the manufacturing time and resulted in a significantly higher PDOs mean count compared to the manually processed tissue from the second week onwards (week 2: 801 vs. 601, P = 0.018; week 3: 1105 vs. 771, P = 0.032; and week 4:1195 vs. 784, P < 0.01). Quality assessment revealed similar rates of tumor-cell apoptosis and proliferation for both manufacturing methods. Therefore, the automated tissue chopper method offers a more efficient approach in terms of time and PDO yield. This method holds promise for drug- or immunotherapy-screening of GBM patients.

Metastasis Associated in Colorectal Cancer 1 (MACC1) mRNA Expression Is Enhanced in Sporadic Vestibular Schwannoma and Correlates to Deafness.

Vestibular schwannoma (VS) are benign cranial nerve sheath tumors of the vestibulocochlear nerve. Their incidence is mostly sporadic, but they can also be associated with NF2-related schwannomatosis (NF2), a hereditary tumor syndrome. Metastasis associated in colon cancer 1 (MACC1) is known to contribute to angiogenesis, cell growth, invasiveness, cell motility and metastasis of solid malignant cancers. In addition, MACC1 may be associated with nonsyndromic hearing impairment. Therefore, we evaluated whether MACC1 may be involved in the pathogenesis of VS. Sporadic VS, recurrent sporadic VS, NF2-associated VS, recurrent NF2-associated VS and healthy vestibular nerves were analyzed for MACC1 mRNA and protein expression by quantitative polymerase chain reaction and immunohistochemistry. MACC1 expression levels were correlated with the patients' clinical course and symptoms. MACC1 mRNA expression was significantly higher in sporadic VS compared to NF2-associated VS (p < 0.001). The latter expressed similar MACC1 concentrations as healthy vestibular nerves. Recurrent tumors resembled the MACC1 expression of the primary tumors. MACC1 mRNA expression was significantly correlated with deafness in sporadic VS patients (p = 0.034). Therefore, MACC1 might be a new molecular marker involved in VS pathogenesis.

Characterization and Optimization of the Tumor Microenvironment in Patient-Derived Organotypic Slices and Organoid Models of Glioblastoma.

While glioblastoma (GBM) is still challenging to treat, novel immunotherapeutic approaches have shown promising effects in preclinical settings. However, their clinical breakthrough is hampered by complex interactions of GBM with the tumor microenvironment (TME). Here, we present an analysis of TME composition in a patient-derived organoid model (PDO) as well as in organotypic slice cultures (OSC). To obtain a more realistic model for immunotherapeutic testing, we introduce an enhanced PDO model. We manufactured PDOs and OSCs from fresh tissue of GBM patients and analyzed the TME. Enhanced PDOs (ePDOs) were obtained via co-culture with PBMCs (peripheral blood mononuclear cells) and compared to normal PDOs (nPDOs) and PT (primary tissue). At first, we showed that TME was not sustained in PDOs after a short time of culture. In contrast, TME was largely maintained in OSCs. Unfortunately, OSCs can only be cultured for up to 9 days. Thus, we enhanced the TME in PDOs by co-culturing PDOs and PBMCs from healthy donors. These cellular TME patterns could be preserved until day 21. The ePDO approach could mirror the interaction of GBM, TME and immunotherapeutic agents and may consequently represent a realistic model for individual immunotherapeutic drug testing in the future.

Intraoperative MRI-Guided Resection Is Not Superior to 5-Aminolevulinic Acid Guidance in Newly Diagnosed Glioblastoma: A Prospective Controlled Multicenter Clinical Trial.

PURPOSE: Prospective data suggested a superiority of intraoperative MRI (iMRI) over 5-aminolevulinic acid (5-ALA) for achieving complete resections of contrast enhancement in glioblastoma surgery. We investigated this hypothesis in a prospective clinical trial and correlated residual disease volumes with clinical outcome in newly diagnosed glioblastoma. METHODS: This is a prospective controlled multicenter parallel-group trial with two center-specific treatment arms (5-ALA and iMRI) and blinded evaluation. The primary end point was complete resection of contrast enhancement on early postoperative MRI. We assessed resectability and extent of resection by an independent blinded centralized review of preoperative and postoperative MRI with 1-mm slices. Secondary end points included progression-free survival (PFS) and overall survival (OS), patient-reported quality of life, and clinical parameters. RESULTS: We recruited 314 patients with newly diagnosed glioblastomas at 11 German centers. A total of 127 patients in the 5-ALA and 150 in the iMRI arm were analyzed in the as-treated analysis. Complete resections, defined as a residual tumor ≤0.175 cm³, were achieved in 90 patients (78%) in the 5-ALA and 115 (81%) in the iMRI arm (P = .79). Incision-suture times (P < .001) were significantly longer in the iMRI arm (316 v 215 [5-ALA] minutes). Median PFS and OS were comparable in both arms. The lack of any residual contrast enhancing tumor (0 cm³) was a significant favorable prognostic factor for PFS (P < .001) and OS (P = .048), especially in methylguanine-DNA-methyltransferase unmethylated tumors (P = .006). CONCLUSION: We could not confirm superiority of iMRI over 5-ALA for achieving complete resections. Neurosurgical interventions in newly diagnosed glioblastoma shall aim for safe complete resections with 0 cm³ contrast-enhancing residual disease, as any other residual tumor volume is a negative predictor for PFS and OS.

BRMS1 in Gliomas-An Expression Analysis.

The metastatic suppressor BRMS1 interacts with critical steps of the metastatic cascade in many cancer entities. As gliomas rarely metastasize, BRMS1 has mainly been neglected in glioma research. However, its interaction partners, such as NFκB, VEGF, or MMPs, are old acquaintances in neurooncology. The steps regulated by BRMS1, such as invasion, migration, and apoptosis, are commonly dysregulated in gliomas. Therefore, BRMS1 shows potential as a regulator of glioma behavior. By bioinformatic analysis, in addition to our cohort of 118 specimens, we determined BRMS1 mRNA and protein expression as well as its correlation with the clinical course in astrocytomas IDH mutant, CNS WHO grade 2/3, and glioblastoma IDH wild-type, CNS WHO grade 4. Interestingly, we found BRMS1 protein expression to be significantly decreased in the aforementioned gliomas, while BRMS1 mRNA appeared to be overexpressed throughout. This dysregulation was independent of patients' characteristics or survival. The protein and mRNA expression differences cannot be finally explained at this stage. However, they suggest a post-transcriptional dysregulation that has been previously described in other cancer entities. Our analyses present the first data on BRMS1 expression in gliomas that can provide a starting point for further investigations.

Tumor Treating Fields (TTFields) Induce Cell Junction Alterations in a Human 3D In Vitro Model of the Blood-Brain Barrier.

In a recent study, we showed in an in vitro murine cerebellar microvascular endothelial cell (cerebEND) model as well as in vivo in rats that Tumor-Treating Fields (TTFields) reversibly open the blood-brain barrier (BBB). This process is facilitated by delocalizing tight junction proteins such as claudin-5 from the membrane to the cytoplasm. In investigating the possibility that the same effects could be observed in human-derived cells, a 3D co-culture model of the BBB was established consisting of primary microvascular brain endothelial cells (HBMVEC) and immortalized pericytes, both of human origin. The TTFields at a frequency of 100 kHz administered for 72 h increased the permeability of our human-derived BBB model. The integrity of the BBB had already recovered 48 h post-TTFields, which is earlier than that observed in cerebEND. The data presented herein validate the previously observed effects of TTFields in murine models. Moreover, due to the fact that human cell-based in vitro models more closely resemble patient-derived entities, our findings are highly relevant for pre-clinical studies.

Glioblastoma-Derived Three-Dimensional Ex Vivo Models to Evaluate Effects and Efficacy of Tumor Treating Fields (TTFields).

Glioblastoma (GBM) displays a wide range of inter- and intra-tumoral heterogeneity contributing to therapeutic resistance and relapse. Although Tumor Treating Fields (TTFields) are effective for the treatment of GBM, there is a lack of ex vivo models to evaluate effects on patients' tumor biology or to screen patients for treatment efficacy. Thus, we adapted patient-derived three-dimensional tissue culture models to be compatible with TTFields application to tissue culture. Patient-derived primary cells (PDPC) were seeded onto murine organotypic hippocampal slice cultures (OHSC), and microtumor development with and without TTFields at 200 kHz was observed. In addition, organoids were generated from acute material cultured on OHSC and treated with TTFields. Lastly, the effect of TTFields on expression of the Ki67 proliferation marker was evaluated on cultured GBM slices. Microtumors exhibited increased sensitivity towards TTFields compared to monolayer cell cultures. TTFields affected tumor growth and viability, as the size of microtumors and the percentage of Ki67-positive cells decreased after treatment. Nevertheless, variability in the extent of the response was preserved between different patient samples. Therefore, these pre-clinical GBM models could provide snapshots of the tumor to simulate patient treatment response and to investigate molecular mechanisms of response and resistance.

Resilience in Lower Grade Glioma Patients.

Current data show that resilience is an important factor in cancer patients' well-being. We aim to explore the resilience of patients with lower grade glioma (LGG) and the potentially influencing factors. We performed a cross-sectional assessment of adult patients with LGG who were enrolled in the LoG-Glio registry. By phone interview, we administered the following measures: Resilience Scale (RS-13), distress thermometer, Montreal Cognitive Assessment Test for visually impaired patients (MoCA-Blind), internalized stigmatization by brain tumor (ISBI), Eastern Cooperative Oncological Group performance status (ECOG), patients' perspective questionnaire (PPQ) and typical clinical parameters. We calculated correlations and multivariate regression models. Of 74 patients who were assessed, 38% of those showed a low level of resilience. Our results revealed significant correlations of resilience with distress (p < 0.001, −0.49), MOCA (p = 0.003, 0.342), ECOG (p < 0.001, −0.602), stigmatization (p < 0.001, −0.558), pain (p < 0.001, −0.524), and occupation (p = 0.007, 0.329). In multivariate analyses, resilience was negatively associated with elevated ECOG (p = 0.020, ß = −0.383) and stigmatization levels (p = 0.008, ß = −0.350). Occupation showed a tendency towards a significant association with resilience (p = 0.088, ß = −0.254). Overall, low resilience affected more than one third of our cohort. Low functional status is a specific risk factor for low resilience. The relevant influence of stigmatization on resilience is a novel finding for patients suffering from a glioma and should be routinely identified and targeted in clinical routine.

Malignant transformation of a cerebral dermoid cyst into a squamous cell carcinoma with malignant intraperitoneal spreading along a ventriculoperitoneal shunt: illustrative case.

BACKGROUND: Malignant progression of intracranial dermoid cysts into squamous cell carcinoma is extremely rare with only three reports published so far. Intracranial dermoid cysts are uncommon benign tumors lined by stratified squamous epithelium of embryonic ectodermal origin. OBSERVATIONS: Here, the authors present the case of a 64-year-old female with a recurrent temporal dermoid cyst. After surgery for the recurrent dermoid cyst, once in the early 1990s and another 16 years later, the patient presented with headache and nausea due to hydrocephalus. After implantation of a ventriculoperitoneal shunt, she deteriorated rapidly and died only 60 days after admission. Autopsy revealed malignant transformation of the epithelial lining of the dermoid cyst into a squamous cell carcinoma resulting in neoplastic meningiosis and intraperitoneal tumor spread along a previously implanted ventriculoperitoneal shunt. LESSONS: Malignant transformation should be considered in patients with dermoid cyst who show new leptomeningeal contrast enhancement. In the case of hydrocephalus, alternatives to peritoneal shunting should be considered.

Tumor Treating Fields (TTFields) Reversibly Permeabilize the Blood-Brain Barrier In Vitro and In Vivo.

Despite the availability of numerous therapeutic substances that could potentially target CNS disorders, an inability of these agents to cross the restrictive blood-brain barrier (BBB) limits their clinical utility. Novel strategies to overcome the BBB are therefore needed to improve drug delivery. We report, for the first time, how Tumor Treating Fields (TTFields), approved for glioblastoma (GBM), affect the BBB's integrity and permeability. Here, we treated murine microvascular cerebellar endothelial cells (cerebEND) with 100-300 kHz TTFields for up to 72 h and analyzed the expression of barrier proteins by immunofluorescence staining and Western blot. In vivo, compounds normally unable to cross the BBB were traced in healthy rat brain following TTFields administration at 100 kHz. The effects were analyzed via MRI and immunohistochemical staining of tight-junction proteins. Furthermore, GBM tumor-bearing rats were treated with paclitaxel (PTX), a chemotherapeutic normally restricted by the BBB combined with TTFields at 100 kHz. The tumor volume was reduced with TTFields plus PTX, relative to either treatment alone. In vitro, we demonstrate that TTFields transiently disrupted BBB function at 100 kHz through a Rho kinase-mediated tight junction claudin-5 phosphorylation pathway. Altogether, if translated into clinical use, TTFields could represent a novel CNS drug delivery strategy.

Effects of Long-Term Temozolomide Treatment on Glioblastoma and Astrocytoma WHO Grade 4 Stem-like Cells.

Glioblastoma leads to a fatal course within two years in more than two thirds of patients. An essential cornerstone of therapy is chemotherapy with temozolomide (TMZ). The effect of TMZ is counteracted by the cellular repair enzyme O6-methylguanine-DNA methyltransferase (MGMT). The MGMT promoter methylation, the main regulator of MGMT expression, can change from primary tumor to recurrence, and TMZ may play a significant role in this process. To identify the potential mechanisms involved, three primary stem-like cell lines (one astrocytoma with the mutation of the isocitrate dehydrogenase (IDH), CNS WHO grade 4 (HGA)), and two glioblastoma (IDH-wildtype, CNS WHO grade 4) were treated with TMZ. The MGMT promoter methylation, migration, proliferation, and TMZ-response of the tumor cells were examined at different time points. The strong effects of TMZ treatment on the MGMT methylated cells were observed. Furthermore, TMZ led to a loss of the MGMT promoter hypermethylation and induced migratory rather than proliferative behavior. Cells with the unmethylated MGMT promoter showed more aggressive behavior after treatment, while HGA cells reacted heterogenously. Our study provides further evidence to consider the potential adverse effects of TMZ chemotherapy and a rationale for investigating potential relationships between TMZ treatment and change in the MGMT promoter methylation during relapse.

SOAT1: A Suitable Target for Therapy in High-Grade Astrocytic Glioma?

Targeting molecular alterations as an effective treatment for isocitrate dehydrogenase-wildtype glioblastoma (GBM) patients has not yet been established. Sterol-O-Acyl Transferase 1 (SOAT1), a key enzyme in the conversion of endoplasmic reticulum cholesterol to esters for storage in lipid droplets (LD), serves as a target for the orphan drug mitotane to treat adrenocortical carcinoma. Inhibition of SOAT1 also suppresses GBM growth. Here, we refined SOAT1-expression in GBM and IDH-mutant astrocytoma, CNS WHO grade 4 (HGA), and assessed the distribution of LD in these tumors. Twenty-seven GBM and three HGA specimens were evaluated by multiple GFAP, Iba1, IDH1 R132H, and SOAT1 immunofluorescence labeling as well as Oil Red O staining. To a small extent SOAT1 was expressed by tumor cells in both tumor entities. In contrast, strong expression was observed in glioma-associated macrophages. Triple immunofluorescence labeling revealed, for the first time, evidence for SOAT1 colocalization with Iba1 and IDH1 R132H, respectively. Furthermore, a notable difference in the amount of LD between GBM and HGA was observed. Therefore, SOAT1 suppression might be a therapeutic option to target GBM and HGA growth and invasiveness. In addition, the high expression in cells related to neuroinflammation could be beneficial for a concomitant suppression of protumoral microglia/macrophages.

The Emesis Trial: Depressive Glioma Patients Are More Affected by Chemotherapy-Induced Nausea and Vomiting.

PURPOSE: Glioma patients face a limited life expectancy and at the same time, they suffer from afflicting symptoms and undesired effects of tumor treatment. Apart from bone marrow suppression, standard chemotherapy with temozolomide causes nausea, emesis and loss of appetite. In this pilot study, we investigated how chemotherapy-induced nausea and vomiting (CINV) affects the patients' levels of depression and their quality of life. METHODS: In this prospective observational multicentre study (n = 87), nausea, emesis and loss of appetite were evaluated with an expanded MASCC questionnaire, covering 10 days during the first and the second cycle of chemotherapy. Quality of life was assessed with the EORTC QLQ-C30 and BN 20 questionnaire and levels of depression with the PHQ-9 inventory before and after the first and second cycle of chemotherapy. RESULTS: CINV affected a minor part of patients. If present, it reached its maximum at day 3 and decreased to baseline level not before day 8. Levels of depression increased significantly after the first cycle of chemotherapy, but decreased during the further course of treatment. Patients with higher levels of depression were more severely affected by CINV and showed a lower quality of life through all time-points. CONCLUSION: We conclude that symptoms of depression should be perceived in advance and treated in order to avoid more severe side effects of tumor treatment. Additionally, in affected patients, delayed nausea was most prominent, pointing toward an activation of the NK1 receptor. We conclude that long acting antiemetics are necessary totreat temozolomide-induced nausea.

Eloquent Lower Grade Gliomas, a Highly Vulnerable Cohort: Assessment of Patients' Functional Outcome After Surgery Based on the LoG-Glio Registry.

Majority of lower grade glioma (LGG) are located eloquently rendering surgical resection challenging. Aim of our study was to assess rate of permanent deficits and its predisposing risk factors. We retrieved 83 patients harboring an eloquently located LGGs from the prospective LoG-Glio Database. Patients without surgery or incomplete postoperative data were excluded. Sign rank test, explorative correlations by Spearman ρ and multivariable regression for new postoperative deficits were calculated. Eloquent region involved predominantly motor (45%) and language (40%). At first follow up after 3 months permanent neuro-logical deficits (NDs) were noted in 39%. Mild deficits remained in 29% and severe deficits in 10%. Complete tumor removal (CTR) was successfully in 62% of intended cases. Postoperative and 3-month follow up National Institute of Health Stroke Score (NIHSS) showed significantly lower values than preoperatively (p<0.001). 38% cases showed a decreased NIHSS at 3-month, while occurrence was only 14% at 9-12-month follow up. 6/7 patients with mild aphasia recovered after 9-12 months, while motor deficits present at 3-month follow up were persistent in majority of patients. Eastern oncology group functional status (ECOG) significantly decreased by surgery (p < 0.001) in 31% of cases. Between 3-month and 9-12-months follow up no significant improvement was seen. In the multivariable model CTR (p=0.019, OR 31.9), and ECOG>0 (p=0.021, OR 8.5) were independent predictors for permanent postoperative deficit according to NIHSS at 3-month according to multivariable regression model. Patients harboring eloquently located LGG are highly vulnerable for permanent deficits. Almost one third of patients have a permanent reduction of their functional status based on ECOG. Risk of an extended resection has to be balanced with the respective oncological benefit. Especially, patients with impaired pre-operative status are at risk for new permanent deficits. There is a relevant improvement of neurological symptoms in the first year after surgery, especially for patients with slight aphasia.

Differences in stem cell marker and osteopontin expression in primary and recurrent glioblastoma.

BACKGROUND: Despite of a multimodal approach, recurrences can hardly be prevented in glioblastoma. This may be in part due to so called glioma stem cells. However, there is no established marker to identify these stem cells. METHODS: Paired samples from glioma patients were analyzed by immunohistochemistry for expression of the following stem cell markers: CD133, Musashi, Nanog, Nestin, octamer-binding transcription factor 4 (Oct4), and sex determining region Y-box 2 (Sox2). In addition, the expression of osteopontin (OPN) was investigated. The relative number of positively stained cells was determined. By means of Kaplan-Meier analysis, a possible association with overall survival by marker expression was investigated. RESULTS: Sixty tissue samples from 30 patients (17 male, 13 female) were available for analysis. For Nestin, Musashi and OPN a significant increase was seen. There was also an increase (not significant) for CD133 and Oct4. Patients with mutated Isocitrate Dehydrogenase-1/2 (IDH-1/2) status had a reduced expression for CD133 and Nestin in their recurrent tumors. Significant correlations were seen for CD133 and Nanog between OPN in the primary and recurrent tumor and between CD133 and Nestin in recurrent tumors. By confocal imaging we could demonstrate a co-expression of CD133 and Nestin within recurrent glioma cells. Patients with high CD133 expression had a worse prognosis (22.6 vs 41.1 months, p = 0.013). A similar trend was seen for elevated Nestin levels (24.9 vs 41.1 months, p = 0.08). CONCLUSIONS: Most of the evaluated markers showed an increased expression in their recurrent tumor. CD133 and Nestin were associated with survival and are candidate markers for further clinical investigation.

The role of beam density and arrangement in non-coplanar IMRT exemplified by the irradiation of brain tumors - Parallels to computed tomographic imaging.

PURPOSE: Parallels between the fields of non-coplanar IMRT and non-coplanar computed tomographic reconstruction are highlighted exemplified by the identification of qualified beam configurations for the irradiation of brain tumors. METHODS AND MATERIALS: Four types of beam configurations, i.e. a pure coplanar, a quasi-isotropic and two transitional arrangements, served to systematically examine the impact of parameters such as the sampling rate and the degree of accessibility on plan quality. The resulting set of treatment techniques was compared by means of a Pinnacle3 based retrospective planning study on 18 brain tumor cases. RESULTS AND DISCUSSION: A consistent ranking of IMRT beam constellations according to plan quality was established, which directly reflects the necessities of high-quality CT imaging. Once a sufficient dense beam sampling is secured (given by compliance to Nyquist's theorem), the quasi-isotropic (QIso) irradiation produced best treatment plans, followed by a coplanar irradiation complemented by a single orthogonal non-coplanar beam (CoPl+1). Beams evenly distributed in two orthogonal planes (2-Pl), although using larger portions of the 4π space, proved to be less favorable as the beam sequence becomes less dense. The most unfavorable technique is the pure coplanar technique (CoPl). Generally, techniques with large interbeam distance, i.e. the 2-Pl technique and, to a lesser extent, QIso, are particularly sensitive to a beam number reduction. CONCLUSIONS: Rules established for high quality non-coplanar tomographic imaging are also relevant for non-coplanar IMRT. In this regard, the degree of coverage of 4π space is less important than a sufficient dense sampling.

First-In-Human Phase I Study of a Next-Generation, Oral, TGFß Receptor 1 Inhibitor, LY3200882, in Patients with Advanced Cancer.

PURPOSE: A novel, selective, next-generation transforming growth factor beta (TGFß) receptor type-1 small molecule inhibitor, LY3200882, demonstrated promising preclinical data. This first-in-human trial evaluated safety, tolerability, recommended phase II dose (RP2D), pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of LY3200882 as monotherapy or with other anticancer agents in patients with advanced cancer. PATIENTS AND METHODS: This phase I multicenter study of oral LY3200882 (NCT02937272) comprised dose escalation, monotherapy expansion in grade 4 glioma, and combination therapy in solid tumors (LY3200882 and PD-L1 inhibitor LY3300054), pancreatic cancer (LY3200882, gemcitabine, and nab-paclitaxel), and head and neck squamous cell cancer (LY3200882, cisplatin, and radiation). RESULTS: Overall, 139 patients with advanced cancer were treated. The majority (93.5%) of patients experienced ≥1 treatment-emergent adverse events (TEAE), with 39.6% LY3200882-related. Grade 3 LY3200882-related toxicities were only observed in combination therapy arms. One patient in the pancreatic cancer arm experienced cardiovascular toxicity. The LY3200882 monotherapy RP2Ds were established in two schedules: 50 mg twice a day 2-weeks-on/2-weeks-off and 35 mg twice a day 3-weeks-on/1-week-off. Four patients with grade 4 glioma had durable Revised Assessment in Neuro Oncology (RANO) partial responses (PR) with LY3200882 monotherapy (n = 3) or LY3200882-LY3300054 combination therapy (n = 1). In treatment-naïve patients with advanced pancreatic cancer, 6 of 12 patients achieved Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 PR and 3 of 12 patients demonstrated stable disease, for an overall 75% disease-control rate with the combination of LY3200882, gemcitabine, and nab-paclitaxel. CONCLUSIONS: LY3200882 as monotherapy and combination therapy was safe and well tolerated with preliminary antitumor activity observed in pancreatic cancer. Further studies to evaluate the efficacy of LY3200882 with gemcitabine and nab-paclitaxel in advanced pancreatic cancer are warranted.

Senescence and associated blood-brain barrier alterations in vitro.

Progressive deterioration of the central nervous system (CNS) is commonly associated with aging. An important component of the neurovasculature is the blood-brain barrier (BBB), majorly made up of endothelial cells joined together by intercellular junctions. The relationship between senescence and changes in the BBB has not yet been thoroughly explored. Moreover, the lack of in vitro models for the study of the mechanisms involved in those changes impede further and more in-depth investigations in the field. For this reason, we herein present an in vitro model of the senescent BBB and an initial attempt to identify senescence-associated alterations within.