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Reardon, David

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Reardon

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Reardon, David

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Now showing 1 - 10 of 10
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    Increased expression of programmed death ligand 1 (PD-L1) in human pituitary tumors
    (Impact Journals LLC, 2016) Mei, Yu; Bi, Wenya; Greenwald, Noah; Du, Ziming; Agar, Nathalie Y. R.; Kaiser, Ursula; Woodmansee, Whitney; Reardon, David; Freeman, Gordon; Fecci, Peter E.; Laws, Edward; Santagata, Sandro; Dunn, Gavin P.; Dunn, Ian
    Purpose Subsets of pituitary tumors exhibit an aggressive clinical courses and recur despite surgery, radiation, and chemotherapy. Because modulation of the immune response through inhibition of T-cell checkpoints has led to durable clinical responses in multiple malignancies, we explored whether pituitary adenomas express immune-related biomarkers that could suggest suitability for immunotherapy. Specifically, programmed death ligand 1 (PD-L1) has emerged as a potential biomarker whose expression may portend more favorable responses to immune checkpoint blockade therapies. We thus investigated the expression of PD-L1 in pituitary adenomas. Methods: PD-L1 RNA and protein expression were evaluated in 48 pituitary tumors, including functioning and non-functioning adenomas as well as atypical and recurrent tumors. Tumor infiltrating lymphocyte populations were also assessed by immunohistochemistry. Results: Pituitary tumors express variable levels of PD-L1 transcript and protein. PD-L1 RNA and protein expression were significantly increased in functioning (growth hormone and prolactin-expressing) pituitary adenomas compared to non-functioning (null cell and silent gonadotroph) adenomas. Moreover, primary pituitary adenomas harbored higher levels of PD-L1 mRNA compared to recurrent tumors. Tumor infiltrating lymphocytes were observed in all pituitary tumors and were positively correlated with increased PD-L1 expression, particularly in the functional subtypes. Conclusions: Human pituitary adenomas harbor PD-L1 across subtypes, with significantly higher expression in functioning adenomas compared to non-functioning adenomas. This expression is accompanied by the presence of tumor infiltrating lymphocytes. These findings suggest the existence of an immune response to pituitary tumors and raise the possibility of considering checkpoint blockade immunotherapy in cases refractory to conventional management.
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    Modeling tumor immunity of mouse glioblastoma by exhausted CD8+ T cells
    (Nature Publishing Group UK, 2018) Nakashima, Hiroshi; Alayo, Quazim; Penaloza-MacMaster, Pablo; Freeman, Gordon; Kuchroo, Vijay; Reardon, David; Fernandez, Soledad; Caligiuri, Michael; Chiocca, E.
    T cell exhaustion occurs during chronic infection and cancers. Programmed cell death protein-1 (PD-1) is a major inhibitory checkpoint receptor involved in T cell exhaustion. Blocking antibodies (Abs) against PD-1 or its ligand, PD-L1, have been shown to reverse T cell exhaustion during chronic infection and cancers, leading to improved control of persistent antigen. However, modeling tumor-specific T cell responses in mouse has been difficult due to the lack of reagents to detect and phenotype tumor-specific immune responses. We developed a novel mouse glioma model expressing a viral epitope derived from lymphocytic choriomeningitis virus (LCMV), which allowed monitoring of tumor-specific CD8 T-cell responses. These CD8 T cells express high levels of PD-1 and are unable to reject tumors, but this can be reversed by anti-PD-1 treatment. These results suggest the efficacy of PD-1 blockade as a treatment for glioblastoma, an aggressive tumor that results in a uniformly lethal outcome. Importantly, this new syngeneic tumor model may also provide further opportunities to characterize anti-tumor T cell exhaustion and develop novel cancer immunotherapies.
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    Progression-free survival as a surrogate endpoint for overall survival in glioblastoma: a literature-based meta-analysis from 91 trials
    (Oxford University Press, 2013) Han, Kelong; Ren, Melanie; Wick, Wolfgang; Abrey, Lauren; Das, Asha; Jin, Jin; Reardon, David
    Background: The aim of this study was to determine correlations between progression-free survival (PFS) and the objective response rate (ORR) with overall survival (OS) in glioblastoma and to evaluate their potential use as surrogates for OS. Method Published glioblastoma trials reporting OS and ORR and/or PFS with sufficient detail were included in correlative analyses using weighted linear regression. Results: Of 274 published unique glioblastoma trials, 91 were included. PFS and OS hazard ratios were strongly correlated; R2 = 0.92 (95% confidence interval [CI], 0.71–0.99). Linear regression determined that a 10% PFS risk reduction would yield an 8.1% ± 0.8% OS risk reduction. R2 between median PFS and median OS was 0.70 (95% CI, 0.59–0.79), with a higher value in trials using Response Assessment in Neuro-Oncology (RANO; R2 = 0.96, n = 8) versus Macdonald criteria (R2 = 0.70; n = 83). No significant differences were demonstrated between temozolomide- and bevacizumab-containing regimens (P = .10) or between trials using RANO and Macdonald criteria (P = .49). The regression line slope between median PFS and OS was significantly higher in newly diagnosed versus recurrent disease (0.58 vs 0.35, P = .04). R2 for 6-month PFS with 1-year OS and median OS were 0.60 (95% CI, 0.37–0.77) and 0.64 (95% CI, 0.42–0.77), respectively. Objective response rate and OS were poorly correlated (R2 = 0.22). Conclusion: In glioblastoma, PFS and OS are strongly correlated, indicating that PFS may be an appropriate surrogate for OS. Compared with OS, PFS offers earlier assessment and higher statistical power at the time of analysis.
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    Rapid Intraoperative Molecular Characterization of Glioma
    (American Medical Association (AMA), 2015) Shankar, Ganesh; Francis, Joshua M.; Rinne, Mikael; Ramkissoon, Shakti H.; Huang, Franklin; Venteicher, Andrew S; Akama-Garren, Elliot H.; Kang, Yun Jee; Lelic, Nina; Kim, James C.; Brown, Loreal E.; Charbonneau, Sarah K; Golby, Alexandra; Sekhar Pedamallu, Chandra; Hoang, Mai; Sullivan, Ryan; Cherniack, Andrew D.; Garraway, Levi; Stemmer-Rachamimov, Anat; Reardon, David; Wen, Patrick; Brastianos, Priscilla; Curry, William; Barker, Frederick; Hahn, William; Nahed, Brian; Ligon, Keith; Louis, David; Cahill, Daniel; Meyerson, Matthew
    IMPORTANCE: Conclusive intraoperative pathologic confirmation of diffuse infiltrative glioma guides the decision to pursue definitive neurosurgical resection. Establishing the intraoperative diagnosis by histologic analysis can be difficult in low-cellularity infiltrative gliomas. Therefore, we developed a rapid and sensitive genotyping assay to detect somatic single-nucleotide variants in the telomerase reverse transcriptase (TERT) promoter and isocitrate dehydrogenase 1 (IDH1). OBSERVATIONS: This assay was applied to tissue samples from 190 patients with diffuse gliomas, including archived fixed and frozen specimens and tissue obtained intraoperatively. Results demonstrated 96% sensitivity (95% CI, 90%–99%) and 100% specificity (95% CI, 95%–100%) for World Health Organization grades II and III gliomas. In a series of live cases, glioma-defining mutations could be identified within 60 minutes, which could facilitate the diagnosis in an intraoperative timeframe. CONCLUSIONS AND RELEVANCE: The genotyping method described herein can establish the diagnosis of low-cellularity tumors like glioma and could be adapted to the point-of-care diagnosis of other lesions that are similarly defined by highly recurrent somatic mutations.
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    Interpretation of meta-analysis evaluating progression-free survival as a surrogate endpoint for overall survival in glioblastoma
    (Oxford University Press, 2015) Han, Kelong; Ren, Melanie; Wick, Wolfgang; Abrey, Lauren; Das, Asha; Jin, Jin; Reardon, David
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    MAPK activation and HRAS mutation identified in pituitary spindle cell oncocytoma
    (Impact Journals LLC, 2016) Miller, Michael B.; Bi, Wenya; Ramkissoon, Lori A.; Kang, Yun Jee; Abedalthagafi, Malak; Knoff, David S.; Agarwalla, Pankaj Kumar; Wen, Patrick; Reardon, David; Alexander, Brian; Laws, Edward; Dunn, Ian; Beroukhim, Rameen; Ligon, Keith; Ramkissoon, Shakti H.
    Pituitary spindle cell oncocytoma (SCO) is an uncommon primary pituitary neoplasm that presents with mass effect on adjacent neurovascular structures, similar to non-hormone-producing pituitary adenomas. To determine the molecular etiology of SCO, we performed exome sequencing on four SCO cases, with matched normal controls, to assess somatic mutations and copy number alterations. Our analysis revealed a low mutation rate and a copy-neutral profile, consistent with the low-grade nature of this tumor. However, we identified a co-occurring somatic HRAS (p.Q61R) activating point mutation and MEN1 frameshift mutation (p.L117fs) present in a primary and recurrent tumor from one patient. Other SCOs demonstrated mutations in SND1 and FAT1, which are associated with MAPK pathway activation. Immunohistochemistry across the SCO cohort demonstrated robust MAPK activity in all cases (n=4), as evidenced by strong phospho-ERK staining, while phospho-AKT levels suggested only basal levels of PI3K pathway activation. Taken together, this identifies the MAPK signaling pathway as a novel therapeutic target for spindle cell oncocytoma, which may offer a powerful adjunct for aggressive tumors refractory to surgical resection.
  • Publication
    Phase II Study of Monthly Pasireotide LAR (SOM230C) for Recurrent or Progressive Meningioma
    (Ovid Technologies (Wolters Kluwer Health), 2014) Norden, A. D.; Ligon, Keith; Hammond, Samantha N.; Muzikansky, A.; Reardon, David; Kaley, Thomas J.; Batchelor, Tracy; Plotkin, Scott; Raizer, Jeffrey J.; Wong, Eric; Drappatz, Jan; Lesser, Glenn J.; Haidar, Sam; Beroukhim, Rameen; Lee, Eudocia; Doherty, Lisa; Lafrankie, Debra; Gaffey, S. C.; Gerard, Mary; Smith, Katrina H.; McCluskey, C.; Phuphanich, Surasak; Wen, Patrick
    Objective: A subset of meningiomas recur after surgery and radiation therapy, but no medical therapy for recurrent meningioma has proven effective. Methods: Pasireotide LAR is a long-acting somatostatin analog that may inhibit meningioma growth. This was a phase II trial in patients with histologically confirmed recurrent or progressive meningioma designed to evaluate whether pasireotide LAR prolongs progression-free survival at 6 months (PFS6). Patients were stratified by histology (atypical [World Health Organization grade 2] and malignant [grade 3] meningiomas in cohort A and benign [grade 3] in cohort B). Results: Eighteen patients were accrued in cohort A and 16 in cohort B. Cohort A had median age 59 years, median Karnofsky performance status 80, 17 (94%) had previous radiation therapy, and 11 (61%) showed high octreotide uptake. Cohort B had median age 52 years, median Karnofsky performance status 90, 11 (69%) had previous radiation therapy, and 12 (75%) showed high octreotide uptake. There were no radiographic responses to pasireotide LAR therapy in either cohort. Twelve patients (67%) in cohort A and 13 (81%) in cohort B achieved stable disease. In cohort A, PFS6 was 17% and median PFS 15 weeks (95% confidence interval: 8–20). In cohort B, PFS6 was 50% and median PFS 26 weeks (12–43). Treatment was well tolerated. Octreotide uptake and insulin-like growth factor–1 levels did not predict outcome. Expression of somatostatin receptor 3 predicted favorable PFS and overall survival. Conclusions: Pasireotide LAR has limited activity in recurrent meningiomas. The finding that somatostatin receptor 3 is associated with favorable outcomes warrants further investigation. Classification of evidence: This study provides Class IV evidence that in patients with recurrent or progressive meningioma, pasireotide LAR does not significantly increase the proportion of patients with PFS at 6 months.
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    Randomized Phase II Study of Cilengitide, an Integrin-Targeting Arginine-Glycine-Aspartic Acid Peptide, in Recurrent Glioblastoma Multiforme
    (American Society of Clinical Oncology (ASCO), 2008) Reardon, David; Fink, Karen L.; Mikkelsen, Tom; Cloughesy, Timothy F.; O, Alison; Plotkin, Scott; Glantz, Michael; Ravin, Paula; Raizer, Jeffrey J.; Rich, Keith M.; Schiff, David; Shapiro, William R.; Burdette-Radoux, Susan; Dropcho, Edward J.; Wittemer, Sabine M.; Nippgen, Johannes; Picard, Martin; Nabors, L. Burt
    Purpose Cilengitide, an inhibitor of αvβ3 and αvβ5 integrin receptors, demonstrated minimal toxicity and durable activity across a wide range of doses administered to adults with recurrent glioblastoma multiforme (GBM) in a prior phase I study. The current multicenter phase II study was conducted to evaluate the activity and safety of cilengitide in GBM patients at first recurrence. Patients and Methods Eligible patients were randomly assigned to receive either 500 or 2,000 mg of cilengitide twice weekly on a continuous basis. Patients were assessed every 4 weeks. The primary end point was 6-month progression-free survival (PFS) rate. Secondary end points included PFS, overall survival (OS), and radiographic response, as well as quality-of-life and pharmacokinetic assessments. Results Eighty-one patients were enrolled, including 41 on the 500-mg arm and 40 on the 2,000-mg arm. The safety profile of cilengitide was excellent, with no significant reproducible toxicities observed on either arm. Antitumor activity was observed in both treatment cohorts but trended more favorably among patients treated with 2,000 mg, including a 6-month PFS of 15% and a median OS of 9.9 months. Conclusion Cilengitide monotherapy is well tolerated and exhibits modest antitumor activity among recurrent GBM patients. Additional studies integrating cilengitide into combinatorial regimens for GBM are warranted.
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    Increased expression of the immune modulatory molecule PD-L1 (CD274) in anaplastic meningioma
    (Impact Journals LLC, 2015) Du, Ziming; Abedalthagafi, Malak; Aizer, Ayal A.; McHenry, Allison R.; Sun, Heather H.; Bray, Mark-Anthony; Viramontes, Omar; Machaidze, Revaz; Brastianos, Priscilla; Reardon, David; Dunn, Ian; Freeman, Gordon; Ligon, Keith; Carpenter, Anne E.; Alexander, Brian; Agar, Nathalie Y.; Rodig, Scott; Bradshaw, Elizabeth M.; Santagata, Sandro
    There are no effective medical treatments for WHO grade III (anaplastic) meningioma. Patients with this high-grade malignancy have a median survival of less than two years. Therapeutics that modulate the mechanisms that inhibit local immune responses in the tumor microenvironment are showing significant and durable clinical responses in patients with treatment refractory high-grade tumors. We examined the immune infiltrate of 291 meningiomas including WHO grade I-III meningiomas using immunohistochemistry and we examined the expression of PD-L1 mRNA by RNAscope in situ hybridization and PD-L1 protein by immunohistochemistry. In meningioma, the tumor infiltrating lymphocytes are predominantly T cells. In anaplastic meningioma, there is a sharp decrease in the number of T cells, including the numbers of CD4+ and CD8+ T cells and cells expressing PD-1 and there is also an increase in the number of FOXP3 expressing immunoregulatory (Treg) cells. PD-L1 expression is increased in anaplastic meningioma – both mRNA and protein. Using patient derived meningioma cell, we confirm that PD-L1 is expressed in meningioma cells themselves, and not solely in infiltrating immune cells. This work indicates that high-grade meningioma harbor an immunosuppressive tumor microenviroment and that increased Treg cells and elevated PD-L1 may contribute to the aggressive phenotype of these tumors.
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    Efficacy and Safety of Immune Checkpoint Blockade for Brain Metastases
    (Future Medicine Ltd, 2019-03-11) Harary, Maya; Reardon, David; Iorgulescu, Julian