Parney, Ian F.

Abstract PURPOSE We investigated the long term impact of SRS and WBRT in two large prospective phase III trials. METHODS Patients with 1–4 BMs +/- resection were randomized to SRS or WBRT. Cognitive deterioration was a drop of >1 standard deviation from baseline in >2/6 cognitive measures (CM). Quality of life (QOL) scores were scored 0–100 point scale. CM and QOL scores were modeled using baseline adjusted Linear Mixed Models (LMM) with uncorrelated random intercept for subject and random slopes for time. Differences over time between groups and the effect of >2 cognitive scores with >2 SD change from baseline were assessed. RESULTS 88 patients were included with median follow up of 24 months. We observed decreasing CM over time (SRS: 4/6; WBRT: 5/6). Mean CM was significantly higher in SRS for Total recall and Delayed Recall at 3, 6, 9, 12 months. More patients in WBRT arm declined 1 SD in >1 and >2 CM at the 3, 6, 9, and 12 months. A 1 SD decline in >3 CM at 1 year was 21% SRS vs 47% WBRT (p=0.02). SRS had fewer patients with a 2 SD decline in >1 CM at every time point. SRS had fewer patients with a 2 SD decline at >2 and >3 CM. WBRT had lower QOL at 3 months, but switched to SRS having lower QOL at 24 months for PWB, EWB, FWB, FactG, BR, and FactBR (p< 0.05). A 2 SD decline in cognition decreased mean FWB by 6.4 units (95% CI: -11, -1.75; p=0.007) and decreased QOL by 5.1 units (95% CI: -7.7, -2.5; p< 0.001). CONCLUSIONS We report the first pooled prospective study demonstrating the long term outcomes of patients with BMs after cranial radiation. WBRT was associated with worse cognitive outcomes. Impaired cognition is associated with worse QOL.

Abstract BACKGROUND Glioblastoma (GBM) is an infiltrative, uniformly fatal brain tumor, treated with surgery, radiation, and Temozolomide (TMZ). Chemoradiation induces a senescent-like phenotype, which contributes to disease recurrence. We recently found that, radiated GBM cells can be eliminated by inhibition of BCL-XL. However, it remains unknown whether p53 is involved in this process and whether the elimination of senescent cells by BCL-XL inhibition could be augmented by MDM2 inhibition, a negative p53 regulator. METHODS p53-mutant (GBM6/GBM123) and p53-WT (GBM39/GBM76) human GBM cells were treated with 5Gy or TMZ following 48 hours of MDM2 inhibitor (AMG232) or vehicle treatment and maintained for seven days to establish a senescent-like phenotype. We evaluated the IC50 for BCL-XL inhibitor (A1331852) in radiated vs. non-radiated cells with or without MDM2 inhibitor pre-treatment. RESULTS MDM2-inhibitor treatment prior to radiation increased the expression of p21 and lead to increased cell death when combined with BCL-XL inhibition in p53-WT GBM cells. IC50 of BCL-XL inhibitor after prior MDM2 pretreatment and radiation in GBM76 was 4.5□M compared to 33.5□M, 18.1□M, and 32.3□M in vehicle without radiation, vehicle with radiation, and MDM2 inhibitor-alone treatment groups, respectively(p=0.0036). The IC50 of BCL-XL inhibitor without MDM2-inhibition in non-irradiated and radiated, as well as pre-administration of MDM2 inhibitor in non-irradiated and radiated GBM39 cells was 5618nM, 16117nM, 3926nM and 276.5nM, respectively(p=0.0003). Conversely, MDM2 co-inhibition with BCL-XL did not lead to increased rates of cell death in p53-mutant cell(p>0.05). CONCLUSION We previously identified that BCL-XL inhibition promotes cell death in senescent GBM cells. We build upon that work, demonstrating the increased rates of cell death can be augmented by MDM2 inhibition, but only in p53-WT cells. These findings highlight a novel therapeutic target for treating latent GBM tumors prior to recurrence, with the additional of MDM2 inhibition greatly increasing the efficacy of BCL-XL targeting agents.

Abstract BACKGROUND Glioblastoma is a fatal infiltrative primary brain tumor, and standard care includes maximal safe surgical resection followed by radiation and Temozolomide (TMZ). Therapy-resistant residual cells persist in a latent state a long time before inevitable recurrence. Conventional radiation and Temozolomide (TMZ) treatment cause oxidative stress and DNA damage resulting senescent-like state of cell-cycle arrest. However, increasing evidence demonstrates escaping senescence leads to tumor recurrence. Thus, the ablation of senescent tumor cells after chemoradiation may be an avenue to limit tumor recurrence. METHODS 100uM TMZ for 7days or 10-20Gy radiation (cesium gamma radiator) was used for senescence induction in human glioblastoma in vitro and confirmed by SA-Beta gal staining and PCR. Replication arrest assessed by automated quantification of cellular confluence (Thermo Scientific Series 8000 WJ Incubator). We evaluated the IC50 for several senolytics targeting multiple SCAPs, including Dasatinib, Quercetin, AMG-232, Fisetin, Onalespib, Navitoclax, and A1331852, and in senescent vs. proliferating cells. RESULTS Among the senolytic tested, the Bcl-XL inhibitors A1331852 and Navitoclax both shown senolytic effect by selectively killing radiated, senescent tumor cells at lower concentrations as compared to 0Gy treated non-senescent cells. Across 12 GBM cell lines, IC50 for senescent cells was 6–500 times lower than non-senescent GBM(p< 0.005). Such differential sensitivity to Bcl-XL inhibition after radiation has also observed by BCL-XL knockdown in radiated glioma. CONCLUSION These findings suggest the potential to harness radiation-induced biology to ablate surviving quiescent cells and demonstrate Bcl-XL dependency as a potential vulnerability of surviving tumor cells after exposure to chemoradiation.

Abstract Patients with glioblastoma (GBM) have a median survival of 15 months despite aggressive treatment. Immunosuppressive monocytes are heavily infiltrated in these tumors and in patients’ circulation. Treatment-related pseudo-progression confounds outcome assessment by MRI. Thus, there is a need for additional non-invasive methods to assess treatment response. Extracellular vesicles (EVs) contain tumor-specific microRNA (miRNA) cargo that could serve as a liquid biopsy to distinguish true progression from treatment-related pseudo-progression. We had found significant differences in plasma EVs molecular profile (i.e. miRNA signatures) between GBM patients and healthy donors. Our overall hypothesis is that these differences reflect the EVs cell of origin. Our goal in this project was to develop a fluorescent staining paradigm by flow cytometry to distinguish EVs from different cells in vitro and determine differences in EV miRNA expression profile between GBM and monocytic cell-derived EVs. Gleolan (5-ALA) is an FDA-approved orally available agent for fluorescence-guided resection of GBM tumors. It is metabolized to protoporphyrin IX (PpIX) in GBM cells but not in non-neoplastic cells and has been reported to aid in the detection of GBM-derived EVs by flow cytometry. However, distinguishing between GBM-derived EVs and EVs from other cells of origin has not been described. We co-cultured human GBM cells (dBT114 or dBT116) and CD14+ monocytes for 72 hours in the presence or absence of 5-ALA. EVs were isolated by ultracentrifugation and stained for CD11b (myeloid cell marker). ImageStream Imaging Flow Cytometry was performed showing clear differentiation between PpIX+ EVs from GBM cells and CD11b+ EVs from monocytes. Interestingly, a small number of double-positive EVs (presumably representing monocyte-derived EVs that had taken up PpIX after phagocytizing GBM cells) were also present. Taken together, we were able to optimize a technique to distinguish EVs originating from GBM and monocytes for further characterization by short non-coding RNA sequencing.

The NCCN Guidelines for Central Nervous System (CNS) Cancers focus on management of adult CNS cancers ranging from noninvasive and surgically curable pilocytic astrocytomas to metastatic brain disease. The involvement of an interdisciplinary team, including neurosurgeons, radiation therapists, oncologists, neurologists, and neuroradiologists, is a key factor in the appropriate management of CNS cancers. Integrated histopathologic and molecular characterization of brain tumors such as gliomas should be standard practice. This article describes NCCN Guidelines recommendations for WHO grade I, II, III, and IV gliomas. Treatment of brain metastases, the most common intracranial tumors in adults, is also described.

Abstract Background Patterns of recurrence and survival with different surgical and radiotherapy (RT) techniques were evaluated to guide RT target volumes for patients with temporal lobe glioma. Methods and Materials This retrospective cohort study included patients with World Health Organization grades II to IV temporal lobe glioma treated with either partial (PTL) or complete temporal lobectomy (CTL) followed by RT covering both the parenchymal and dural resection bed (whole-cavity radiotherapy [WCRT]) or the parenchymal resection bed only (partial-cavity radiotherapy [PCRT]). Patterns of recurrence, progression-free survival (PFS) and overall survival (OS) were evaluated. Results Fifty-one patients were included and 84.3% of patients had high-grade glioma (HGG). CTL and PTL were performed for 11 (21.6%) and 40 (78.4%) patients, respectively. Median RT dose was 60 Gy (range, 40-76 Gy). There were 82.4% and 17.6% of patients who received WCRT and PCRT, respectively. Median follow-up time was 18.4 months (range, 4-161 months). Forty-six patients (90.2%) experienced disease recurrence, most commonly at the parenchymal resection bed (76.5%). No patients experienced an isolated dural recurrence. The median PFS and OS for the PCRT and WCRT cohorts were 8.6 vs 10.8 months (P = .979) and 19.9 vs 18.6 months (P = .859), respectively. PCRT was associated with a lower RT dose to the brainstem, optic, and ocular structures, hippocampus, and pituitary. Conclusion We identified no isolated dural recurrence and similar PFS and OS regardless of postoperative RT volume, whereas PCRT was associated with dose reduction to critical structures. Omission of dural RT may be considered a reasonable alternative approach. Further validation with larger comparative studies is warranted.

OBJECTIVE Acute traumatic subdural hematoma (atSDH) can be a life-threatening neurosurgical emergency that necessitates immediate evacuation. The elderly population can be particularly vulnerable to tearing bridging veins. The aim of this study was to evaluate inpatient morbidity and mortality, as well as predictors of inpatient mortality, in a national trauma database. METHODS The authors queried the 2016–2017 National Trauma Data Bank registry for patients aged 65 years and older who had undergone evacuation of atSDH. Patients were categorized into three age groups: 65–74, 75–84, and 85+ years. A multivariable logistic regression model was fitted for inpatient mortality adjusting for age group, sex, race, presenting Glasgow Coma Scale (GCS) category (3–8, 9–12, and 13–15), Injury Severity Score, presence of coagulopathy, presence of additional hemorrhages (epidural hematoma [EDH], intraparenchymal hematoma [IPH], and subarachnoid hemorrhage [SAH]), presence of midline shift > 5 mm, and pupillary reactivity (both, one, or none). RESULTS A total of 2508 patients (35% females) were analyzed. Age distribution was as follows: 990 patients at 65–74 years, 1096 at 75–84, and 422 at 85+. Midline shift > 5 mm was present in 72% of cases. With regard to additional hemorrhages, SAH was present in 21%, IPH in 10%, and EDH in 2%. Bilaterally reactive pupils were noted in 90% of patients. A major complication was observed in 14.4% of patients, and the overall mortality rate was 18.3%. In the multivariable analysis, the presenting GCS category was found to be the strongest predictor of postoperative inpatient mortality (3–8 vs 13–15: OR 3.63, 95% CI 2.68–4.92, p < 0.001; 9–12 vs 13–15: OR 2.64, 95% CI 1.79–3.90, p < 0.001; 30% of overall variation), followed by the presence of SAH (OR 2.86, 95% CI 2.21–3.70, p < 0.001; 25% of overall variation) and the presence of midline shift > 5 mm (OR 2.40, 95% CI 1.74–3.32, p < 0.001; 11% of overall variation). Model discrimination was excellent (c-index 0.81). Broken down by age decile group, mortality increased from 8.0% to 15.4% for GCS 13–15 to around 36% for GCS 9–12 to almost as high as 60% for GCS 3–8, particularly in those aged 85 years and older. CONCLUSIONS The present results from a national trauma database will, the authors hope, assist surgeons in preoperative discussions with patients and their families with regard to expected postoperative outcomes following surgical evacuation of an atSDH.

Abstract Immunosuppression of unknown aetiology is a hallmark feature of glioblastoma and is characterized by decreased CD4 T-cell counts and downregulation of major histocompatibility complex class II expression on peripheral blood monocytes in patients. This immunosuppression is a critical barrier to the successful development of immunotherapies for glioblastoma. We recapitulated the immunosuppression observed in glioblastoma patients in the C57BL/6 mouse and investigated the aetiology of low CD4 T-cell counts. We determined that thymic involution was a hallmark feature of immunosuppression in three distinct models of brain cancer, including mice harbouring GL261 glioma, B16 melanoma, and in a spontaneous model of diffuse intrinsic pontine glioma. In addition to thymic involution, we determined that tumour growth in the brain induced significant splenic involution, reductions in peripheral T cells, reduced MHC II expression on blood leucocytes, and a modest increase in bone marrow resident CD4 T cells. Using parabiosis we report that thymic involution, declines in peripheral T-cell counts, and reduced major histocompatibility complex class II expression levels were mediated through circulating blood-derived factors. Conversely, T-cell sequestration in the bone marrow was not governed through circulating factors. Serum isolated from glioma-bearing mice potently inhibited proliferation and functions of T cells both in vitro and in vivo. Interestingly, the factor responsible for immunosuppression in serum is non-steroidal and of high molecular weight. Through further analysis of neurological disease models, we determined that the immunosuppression was not unique to cancer itself, but rather occurs in response to brain injury. Non-cancerous acute neurological insults also induced significant thymic involution and rendered serum immunosuppressive. Both thymic involution and serum-derived immunosuppression were reversible upon clearance of brain insults. These findings demonstrate that brain cancers cause multifaceted immunosuppression and pinpoint circulating factors as a target of intervention to restore immunity.

Abstract Background Glioblastoma, the most common primary malignant brain tumor, is nearly universally fatal by 5 years. Dendritic cell vaccines are promising but often limited clinically by antigen choice, dendritic cell potency, and/or manufacturing yield. We optimized vaccine manufacture, generating potent mature autologous dendritic cells pulsed with allogeneic glioblastoma lysates. Methods Platelet lysate-based supplement was used to establish human glioblastoma cell lines. Phenotype and genotype were assessed. An improved culture technique to generate mature dendritic cells from glioblastoma patients’ monocytes was developed. The ability of T cells stimulated with autologous dendritic cells pulsed with allogeneic glioblastoma cell lysate to kill HLA-A2-matched glioblastoma cells was assessed. Results Glioblastoma cell lines established with platelet lysate supplement grew faster and expressed more stem-like markers than lines grown in neural stem cell media or in the presence of serum. They expressed a variety of glioma-associated antigens and had genomic abnormalities characteristic of glioblastoma stable up to 15 doublings. Unlike standard culture techniques, our optimized technique produced high levels of mature dendritic cells from glioblastoma patients’ monocytes. Autologous T cells stimulated with mature dendritic cells pulsed with allogeneic glioblastoma cell line lysate briskly killed HLA-A2-matched glioblastoma cells. Conclusions Our glioblastoma culture method provides a renewable source for a broad spectrum glioblastoma neoantigens while our dendritic cell culture technique results in more mature dendritic cells in glioblastoma patients than standard techniques. This broadly applicable strategy could be easily integrated into patient care.