Person: Plotkin, Scott
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Plotkin
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Scott
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Plotkin, Scott
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Publication Plasma S100β is not a useful biomarker for tumor burden in neurofibromatosis(Elsevier BV, 2013) Smith, Miriam J.; Esparza, Sonia; Merker, Vanessa; Muzikansky, Alona; Bredella, Miriam; Harris, Gordon; Kassarjian, Ara; Cai, Wenli; Walker, James; Mautner, Victor F.; Plotkin, ScottObjectives Neurofibromatosis 1 (NF1), NF2, and schwannomatosis are characterized by a predisposition to develop multiple neurofibromas and schwannomas. Currently, there is no blood test to estimate tumor burden in patients with these disorders. We explored whether S100β would act as a biomarker of tumor burden in NF since S100β is a classic immunohistochemical marker of astrocytes, oligodendrocytes and Schwann cells and a small study showed S100β concentrations correlate with the volume of vestibular schwannomas. Design and methods We calculated whole-body tumor burden in subjects with NF1, NF2, and schwannomatosis using whole-body MRI (WBMRI) and measured the concentration of S100β in plasma using ELISA. We used chi-square tests and Spearman rank correlations to test the relationship between S100β levels and whole-body tumor burden. Results 127 consecutive patients were enrolled in the study (69 NF1 patients, 28 NF2 patients, and 30 schwannomatosis patients). The median age was 40 years, 43% were male, and median whole-body tumor volume was 26.9 mL. There was no relationship between the presence of internal tumors and the presence of detectable S100β in blood for the overall group or for individual diagnoses (p > 0.05 by chi-square for all comparisons). Similarly, there was no correlation between whole-body tumor volume and S100β concentration for the overall group or for individual diagnoses (p > 0.05 by Spearman for all comparisons). Conclusions Plasma S100β is not a useful biomarker for tumor burden in the neurofibromatoses. Further work is needed to identify a reliable biomarker of tumor burden in NF patients.Publication Bevacizumab treatment for symptomatic spinal ependymomas in neurofibromatosis type 2(Wiley-Blackwell, 2015) Farschtschi, S.; Merker, V. L.; Wolf, D.; Schuhmann, M.; Blakeley, J.; Plotkin, Scott; Hagel, C.; Mautner, V. F.Background Neurofibromatosis type 2 (NF2) is a tumor suppressor syndrome associated with vestibular schwannomas, meningiomas, and spinal ependymomas. There have been anecdotal reports of radiographic response of spinal ependymomas in NF2 patients being treated for progressive vestibular schwannomas with bevacizumab, a monoclonal antibody against vascular endothelial growth factor (VEGF). Aims The aim of this study was to review the clinical effects of bevacizumab treatment for symptomatic, NF2-associated ependymomas Methods We conducted a retrospective review of all patients with NF2 treated with bevacizumab for symptomatic ependymoma at three NF2 specialty centers. Tumor size was evaluated by linear measurements; radiographic response was defined as >20% reduction in tumor size. We also performed immunohistochemical evaluation of NF2-associated symptomatic ependymomas from five patients, including two from this clinical series. Results Eight patients with NF2 and symptomatic ependymoma were treated with bevacizumab. All patients had subjective clinical improvement with bevacizumab, although only five of eight patients evaluated had radiographic response. All tumors expressed VEGF-R2. Four of five evaluated ependymomas expressed VEGF-R1; one without VEGF-R1 expression was from a patient who showed clinical but not radiographic response. Conclusions Treatment using bevacizumab improved symptoms related to NF2-associated ependymomas, often without concurrent radiographic responPublication Traditional and systems biology based drug discovery for the rare tumor syndrome neurofibromatosis type 2(Public Library of Science, 2018) Allaway, Robert; Angus, Steve P.; Beauchamp, Roberta L.; Blakeley, Jaishri O.; Bott, Marga; Burns, Sarah S.; Carlstedt, Annemarie; Chang, Long-Sheng; Chen, Xin; Clapp, D. Wade; Desouza, Patrick A.; Erdin, Serkan; Fernandez-Valle, Cristina; Guinney, Justin; Gusella, James; Haggarty, Stephen; Johnson, Gary L.; La Rosa, Salvatore; Morrison, Helen; Petrilli, Alejandra M.; Plotkin, Scott; Pratap, Abhishek; Ramesh, Vijaya; Sciaky, Noah; Stemmer-Rachamimov, Anat; Stuhlmiller, Tim J.; Talkowski, Michael; Welling, Duane; Yates, Charles W.; Zawistowski, Jon S.; Zhao, Wen-NingNeurofibromatosis 2 (NF2) is a rare tumor suppressor syndrome that manifests with multiple schwannomas and meningiomas. There are no effective drug therapies for these benign tumors and conventional therapies have limited efficacy. Various model systems have been created and several drug targets have been implicated in NF2-driven tumorigenesis based on known effects of the absence of merlin, the product of the NF2 gene. We tested priority compounds based on known biology with traditional dose-concentration studies in meningioma and schwann cell systems. Concurrently, we studied functional kinome and gene expression in these cells pre- and post-treatment to determine merlin deficient molecular phenotypes. Cell viability results showed that three agents (GSK2126458, Panobinostat, CUDC-907) had the greatest activity across schwannoma and meningioma cell systems, but merlin status did not significantly influence response. In vivo, drug effect was tumor specific with meningioma, but not schwannoma, showing response to GSK2126458 and Panobinostat. In culture, changes in both the transcriptome and kinome in response to treatment clustered predominantly based on tumor type. However, there were differences in both gene expression and functional kinome at baseline between meningioma and schwannoma cell systems that may form the basis for future selective therapies. This work has created an openly accessible resource (www.synapse.org/SynodosNF2) of fully characterized isogenic schwannoma and meningioma cell systems as well as a rich data source of kinome and transcriptome data from these assay systems before and after treatment that enables single and combination drug discovery based on molecular phenotype.Publication Resolving the phylogenetic origin of glioblastoma via multifocal genomic analysis of pre-treatment and treatment-resistant autopsy specimens(Nature Publishing Group UK, 2017) Brastianos, Priscilla; Nayyar, Naema; Rosebrock, Daniel; Leshchiner, Ignaty; Gill, Corey M.; Livitz, Dimitri; Bertalan, Mia S.; D’Andrea, Megan; Hoang, Kaitlin; Aquilanti, Elisa; Chukwueke, Ugonma; Kaneb, Andrew; Chi, Andrew; Plotkin, Scott; Gerstner, Elizabeth; Frosch, Mathew P.; Suva, Mario; Cahill, Daniel; Getz, Gad; Batchelor, TracyGlioblastomas are malignant neoplasms composed of diverse cell populations. This intratumoral diversity has an underlying architecture, with a hierarchical relationship through clonal evolution from a common ancestor. Therapies are limited by emergence of resistant subclones from this phylogenetic reservoir. To characterize this clonal ancestral origin of recurrent tumors, we determined phylogenetic relationships using whole exome sequencing of pre-treatment IDH1/2 wild-type glioblastoma specimens, matched to post-treatment autopsy samples (n = 9) and metastatic extracranial post-treatment autopsy samples (n = 3). We identified “truncal” genetic events common to the evolutionary ancestry of the initial specimen and later recurrences, thereby inferring the identity of the precursor cell population. Mutations were identified in a subset of cases in known glioblastoma genes such as NF1(n = 3), TP53(n = 4) and EGFR(n = 5). However, by phylogenetic analysis, there were no protein-coding mutations as recurrent truncal events across the majority of cases. In contrast, whole copy-loss of chromosome 10 (12 of 12 cases), copy-loss of chromosome 9p21 (11 of 12 cases) and copy-gain in chromosome 7 (10 of 12 cases) were identified as shared events in the majority of cases. Strikingly, mutations in the TERT promoter were also identified as shared events in all evaluated pairs (9 of 9). Thus, we define four truncal non-coding genomic alterations that represent early genomic events in gliomagenesis, that identify the persistent cellular reservoir from which glioblastoma recurrences emerge. Therapies to target these key early genomic events are needed. These findings offer an evolutionary explanation for why precision therapies that target protein-coding mutations lack efficacy in GBM.Publication Pain correlates with germline mutation in schwannomatosis(Wolters Kluwer Health, 2018) Jordan, Justin; Smith, Miriam J.; Walker, James A.; Erdin, Serkan; Talkowski, Michael E.; Merker, Vanessa L.; Ramesh, Vijaya; Cai, Wenli; Harris, Gordon; Bredella, Miriam; Seijo, Marlon; Suuberg, Alessandra; Gusella, James; Plotkin, ScottAbstract Schwannomatosis has been linked to germline mutations in the SMARCB1 and LZTR1 genes, and is frequently associated with pain. In a cohort study, we assessed the mutation status of 37 patients with clinically diagnosed schwannomatosis and compared to clinical data, whole body MRI (WBMRI), visual analog pain scale, and Short Form 36 (SF-36) bodily pain subscale. We identified a germline mutation in LZTR1 in 5 patients (13.5%) and SMARCB1 in 15 patients (40.5%), but found no germline mutation in 17 patients (45.9%). Peripheral schwannomas were detected in 3 LZTR1-mutant (60%) and 10 SMARCB1-mutant subjects (66.7%). Among those with peripheral tumors, the median tumor number was 4 in the LZTR1 group (median total body tumor volume 30 cc) and 10 in the SMARCB1 group (median volume 85cc), (P=.2915 for tumor number and P = .2289 for volume). mutation was associated with an increased prevalence of spinal schwannomas (100% vs 41%, P = .0197). The median pain score was 3.9/10 in the LZTR1 group and 0.5/10 in the SMARCB1 group (P = .0414), and SF-36 pain-associated quality of life was significantly worse in the LZTR1 group (P = .0106). Pain scores correlated with total body tumor volume (rho = 0.32471, P = .0499), but not with number of tumors (rho = 0.23065, P = .1696). We found no significant difference in quantitative tumor burden between mutational groups, but spinal schwannomas were more common in LZTR1-mutant patients. Pain was significantly higher in LZTR1-mutant than in SMARCB1-mutant patients, though spinal tumor location did not significantly correlate with pain. This suggests a possible genetic association with schwannomatosis-associated pain.Publication Quality of life among adult patients with neurofibromatosis 1, neurofibromatosis 2 and schwannomatosis: a systematic review of the literature(Springer Nature, 2013) Vranceanu, Ana-Maria; Merker, Vanessa; Park, Elyse; Plotkin, ScottThe aim of this study was to review the literature on quality of life among adult patients with neurofibromatosis 1, neurofibromatosis 2 and schwannomatosis, and to identify the specific aspects of quality of life that were studied and reported in this population. We also set out to report predictors of quality of life. Published research reports were included if they described quality of life in this population and met methodological quality according to a list of predefined criteria. Eight studies (7 in NF1, 1 in NF2, 0 in schwannomatosis), conducted between 2001 and 2013, met inclusion criteria. The methodological quality of the eight studies was mostly high according to ratings by predefined criteria. Most studies reported that patients with NF experience decreased quality of life when compared to the general population. Visibility and disease severity were strong predictors of skin-specific quality of life in NF1 patients. However, the majority of findings regarding predictors of quality of life were weak or inconclusive. Given the decreased quality of life in NF patients, it is important to examine more comprehensively the psychosocial factors in this population, especially in patients with NF2 and schwannomatosis. Mind body interventions that address these domains may provide comprehensive and efficacious long term treatment.Publication Outcomes of preimplantation genetic diagnosis in neurofibromatosis type 1(Elsevier BV, 2015) Merker, Vanessa; Murphy, Timothy P.; Hughes, J. Bryan; Muzikansky, Alona; Hughes, Mark; Souter, Irene; Plotkin, ScottObjective To examine the effect of patient and facility level factors on the success of preimplantation genetic diagnosis (PGD) in patients with neurofibromatosis 1 (NF1). Design Retrospective review. Setting Large PGD reference laboratory. Patient(s) All patients with NF1 referred from June 2004 to May 2013. Intervention(s) None. Main Outcome Measure(s) Embryos' NF1 mutation status and live birth rates. Result(s) Seventy-seven couples underwent 156 PGD cycles during the study period. The average maternal age at the time of embryo biopsy was 33.2 years. The majority of embryos had a day 3 single blastomere biopsy without aneuploidy screening. A diagnosis was obtained for 80% of biopsied embryos; 20% of biopsies were nondiagnostic due to technical failures. Diagnosis was more often obtained for embryos of parents with familial disease and for embryos biopsied at centers that referred multiple NF1 cases. Among diagnosed embryos, 483/1,060 (46%) were unaffected by the parental NF1 mutation. Twenty-two (14%) of the 156 cycles had a confirmed live birth; if the observed success rate is applied to cycles with unknown outcomes, 33/156 (21%) cycles are expected to have resulted in live birth. In multivariate logistic regression, having a live birth was significantly associated with having more unaffected embryos available for transfer (odds ratio 1.33 per additional embryo, 95% confidence interval 1.02–1.72). Conclusion(s) Advances in biopsy and diagnostic techniques which increase the number of unaffected embryos identified may improve live birth rates for patients with NF1. Clinicians should counsel patients about their fertility and reproductive options early, with the use of disease-specific data, to set appropriate expectations for the PGD process.Publication Health-related Quality of Life of Individuals With Neurofibromatosis Type 2(Ovid Technologies (Wolters Kluwer Health), 2016) Merker, Vanessa; Bergner, Amanda L.; Vranceanu, Ana-Maria; Muzikansky, Alona; Slattery, William; Plotkin, ScottObjective: To explore health-related quality of life (HRQoL) reported by individuals with neurofibromatosis type 2 (NF2) and to assess for correlations between HRQoL and objective measures of disease manifestations. Study Design: Prospective observational study. Setting: Seven international NF2 centers. Subjects: Eighty-one individuals with NF2, 73 adults (>18 years) and 8 children/adolescents (10–17 years). Outcome Measures: Quality of life was measured by Short Form-36 (SF-36) norm-based scores. Objective clinical measures were hearing (categorized by word-recognition scores), facial function (categorized by the House–Brackmann scale) and the volume of subjects’ larger vestibular schwannoma (VS). Results: At baseline, adults showed significant deficits in all but two subscales of the SF-36 compared with age- and gender-adjusted United States population norms. In linear regression models including age, gender, inheritance status, hearing, facial weakness and VS volume, demographic and functional measures showed no relationship to any SF-36 subscale. Larger baseline VS volume was significantly related to reduced physical role performance, reduced mental health, and increased pain (p < 0.05). In bivariate analysis, previous VS surgery was not significantly associated with baseline HRQoL; receipt of VS surgery or tumor growth during the observation period was not significantly associated with changes in HRQoL. Conclusion: NF2 patients report reduced HRQoL in physical, social, and mental domains, but this was not significantly related to objective measures of hearing or facial functioning. Larger baseline VS volume negatively impacted patient-reported HRQoL whereas VS surgery or tumor growth did not. Future studies should explore the relationship between tumor volume and HRQoL and psychosocial factors that may moderate this relationship.Publication Pregnancy complications in women with rare tumor suppressor syndromes affecting central and peripheral nervous system(Elsevier BV, 2015) Terry, Anna R.; Merker, Vanessa; Barker, Frederick; Leffert, Lisa; Bateman, Brian; Souter, Irene; Plotkin, ScottNeurofibromatosis type 2 (NF2), tuberous sclerosis (TS), and von Hippel-Lindau disease (VHL) are tumor suppressor syndromes characterized by multiple benign tumors of the peripheral and central nervous system.1 These tumors may lead to an enhanced obstetric risk in female patients, but it is currently unknown whether women with NF2, TS, or VHL experience increased rates of adverse pregnancy outcomes. Current data consist primarily of case series, even the largest of which may lack power because of the small sample sizes.Publication Relationship between whole-body tumor burden, clinical phenotype, and quality of life in patients with neurofibromatosis(Wiley-Blackwell, 2014) Merker, Vanessa; Bredella, Miriam; Cai, Wenli; Kassarjian, Ara; Harris, Gordon; Muzikansky, Alona; Nguyen, Rosa; Mautner, Victor F.; Plotkin, ScottPatients with neurofibromatosis 1 (NF1), NF2, and schwannomatosis share a predisposition to develop multiple nerve sheath tumors. Previous studies have demonstrated that patients with NF1 and NF2 have reduced quality of life (QOL), but no studies have examined the relationship between whole-body tumor burden and QOL in these patients. We administered a QOL questionnaire (the SF-36) and a visual analog pain scale (VAS) to a previously described cohort of adult neurofibromatosis patients undergoing whole-body MRI. One-sample t-tests were used to compare norm-based SF-36 scores to weighted population means. Spearman correlation coefficients and multiple linear regression analyses controlling for demographic and disease-specific clinical variable were used to relate whole-body tumor volume to QOL scales. Two hundred forty-five patients (142 NF1, 53 NF2, 50 schwannomatosis) completed the study. Subjects showed deficits in selected subscales of the SF-36 compared to adjusted general population means. In bivariate analysis, increased tumor volume was significantly associated with pain in schwannomatosis patients, as measured by the SF-36 bodily pain subscale (rho = −0.287, P = 0.04) and VAS (rho = 0.34, P = 0.02). Regression models for NF2 patients showed a positive relationship between tumor burden and increased pain, as measured by the SF-36 (P = 0.008). Patients with NF1, NF2, and schwannomatosis suffer from reduced QOL, although only pain shows a clear relationship to patient's overall tumor burden. These findings suggest that internal tumor volume is not a primary contributor to QOL and emphasize the need for comprehensive treatment approaches that go beyond tumor-focused therapies such as surgery by including psychosocial interventions.