Intraoperative Integrated Diagnostic System for Malignant Central Nervous System Tumors

PURPOSE

The 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors uses an integrated approach involving histopathology and molecular profiling. Because majority of adult malignant brain tumors are gliomas and primary CNS lymphomas (PCNSL), rapid differentiation of these diseases is required for therapeutic decisions. In addition, diffuse gliomas require molecular information on single-nucleotide variants (SNV), such as IDH1/2. Here, we report an intraoperative integrated diagnostic (i-ID) system to classify CNS malignant tumors, which updates legacy frozen-section (FS) diagnosis through incorporation of a qPCR-based genotyping assay.

EXPERIMENTAL DESIGN

FS evaluation, including GFAP and CD20 rapid IHC, was performed on adult malignant CNS tumors. PCNSL was diagnosed through positive CD20 and negative GFAP immunostaining. For suspected glioma, genotyping for IDH1/2, TERT SNV, and CDKN2A copy-number alteration was routinely performed, whereas H3F3A and BRAF SNV were assessed for selected cases. i-ID was determined on the basis of the 2021 WHO classification and compared with the permanent integrated diagnosis (p-ID) to assess its reliability.

RESULTS

After retrospectively analyzing 153 cases, 101 cases were prospectively examined using the i-ID system. Assessment of IDH1/2, TERT, H3F3AK27M, BRAFV600E, and CDKN2A alterations with i-ID and permanent genomic analysis was concordant in 100%, 100%, 100%, 100%, and 96.4%, respectively. Combination with FS and intraoperative genotyping assay improved diagnostic accuracy in gliomas. Overall, i-ID matched with p-ID in 80/82 (97.6%) patients with glioma and 18/19 (94.7%) with PCNSL.

CONCLUSIONS

The i-ID system provides reliable integrated diagnosis of adult malignant CNS tumors.

Arteries Around the Superior Limiting Sulcus: Motor Complication Avoidance in Insular and Insulo-Opercular Surgery

BACKGROUND AND OBJECTIVES

Insulo-opercular surgery can cause ischemic motor complications. A source of this is the arteries around the superior limiting sulcus (SLS), which reach the corona radiata, but the detailed anatomy remains unclear. To characterize arteries around the SLS including the long insular arteries (LIAs) and long medullary arteries, we classified them and examined their distribution in relation to the SLS, which helps reduce the risk of ischemia.

METHODS

Twenty adult cadaveric hemispheres were studied. Coronal brain slices were created perpendicular to the SLS representing insular gyri (anterior short, middle short, posterior short, anterior long, and posterior long). The arteries within 10-mm proximity of the SLS that reached the corona radiata were excavated and classified by the entry point.

RESULTS

A total of 122 arteries were identified. Sixty-three (52%), 20 (16%), and 39 (32%) arteries penetrated the insula (LIAs), peak of the SLS, and operculum (long medullary arteries), respectively. 100 and six (87%) arteries penetrated within 5 mm of the peak of the SLS. The arteries were distributed in the anterior short gyrus (19%), middle short gyrus (17%), posterior short gyrus (20%), anterior long gyrus (19%), and posterior long gyrus (25%). Seven arteries (5.7%) had anastomoses after they penetrated the parenchyma.

CONCLUSION

Approximately 90% of the arteries that entered the parenchyma and reached the corona radiata were within a 5-mm radius of the SLS in both the insula and operculum side. This suggests that using the SLS as a landmark during insulo-opercular surgery can decrease the chance of ischemia.

Genetic alterations that deregulate RB and PDGFRA signaling pathways drive tumor progression in IDH2-mutant astrocytoma

In IDH-mutant astrocytoma, IDH2 mutation is quite rare and biological mechanisms underlying tumor progression in IDH2-mutant astrocytoma remain elusive. Here, we report a unique case of IDH2 mutant astrocytoma, CNS WHO grade 3 that developed tumor progression. We performed a comprehensive genomic and epigenomic analysis for primary and recurrent tumors and found that both tumors harbored recurrent IDH2R172K and TP53R248W mutation with CDKN2A/B hemizygous deletion. We also found amplifications of CDK4 and MDM2 with PDGFRA gain in the recurrent tumor and upregulated protein expressions of these genes. We further developed, for the first time, a xenograft mouse model of IDH2R172K and TP53R248W mutant astrocytoma from the recurrent tumor, but not from the primary tumor. Consistent with parent recurrent tumor cells, amplifications of CDK4 and MDM2 and PDGFRA gain were found, while CDKN2A/B was identified as homozygous deletion in the xenografts, qualifying for integrated diagnosis of astrocytoma, IDH2-mutant, CNS WHO grade 4. Cell viability assay found that CDK4/6 inhibitor and PDGFR inhibitor potently decreased cell viability in recurrent tumor cells, as compared to primary tumor cells. These findings suggest that gene alterations that activate retinoblastoma (RB) signaling pathways and PDGFR may drive tumor progression and xenograft formation in IDH2-mutant astrocytoma, which is equivalent to progressive IDH1-mutant astrocytoma. Also, our findings suggest that these genomic alterations may represent therapeutic targets in IDH2-mutant astrocytoma.

Proof-of-Principle Experiment for Testing Strong-Field Quantum Electrodynamics with Exotic Atoms: High Precision X-Ray Spectroscopy of Muonic Neon

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst)  eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

Thigh leiomyosarcoma-derived brain metastasis with intracerebral hematoma: A case report and literature review

Background:

Brain metastases with hematoma are clinically important as they indicate the potential for rapid neurological deterioration. Non-uterine leiomyosarcoma-derived brain metastases are particularly rare, and their clinical features, including the bleeding rate, are unclear. Herein, we present a rare case of thigh leiomyosarcoma-derived brain metastasis with intratumoral hematoma and review previous case reports.

Case Description:

A 68-year-old man with a right thigh leiomyosarcoma presented with multiple brain metastases. The patient received stereotactic radiotherapy; however, he reported sudden right-sided hemiparesis. We found a right frontal irradiated lesion with intratumoral hemorrhage and performed gross total tumor resection. Histopathological examination showed highly atypical cells with prominent necrosis and hemorrhage. Abnormal thin-walled vessels were prominent within the brain tumor, and vascular endothelial growth factor was diffusely expressed immunohistopathologically. To date, 11 cases of brain metastasis from non-uterine leiomyosarcoma, including the present case, have been reported. Of note, six patients had hemorrhage. Three out of six patients presented with hemorrhage before therapeutic intervention, three cases were from residual sites after surgery or radiation.

Conclusion:

More than half the patients with non-uterine leiomyosarcoma-derived brain metastases presented with intracerebral hemorrhage. Furthermore, these patients are at risk of developing rapid neurological deterioration due to intracerebral hemorrhage.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Association between parental occupations, educational levels, and household income and children's psychological adjustment in Japan

OBJECTIVES

Most research on the association between parental or family socio-economic status and psychological adjustment in children has been performed mainly in Western countries, while there is limited evidence of such research in Asian countries. We examined the association of parental occupation and educational levels and household income with children's psychological adjustment in Japan.

STUDY DESIGN

This was a cross-sectional study.

METHODS

Study subjects were 6329 children aged 3 years. Children's psychological adjustment was assessed using the Strengths and Difficulties Questionnaire.

RESULTS

Compared with having an unemployed father, having a father who worked in an administrative and managerial or clerical job was associated with a lower prevalence of peer problems. Compared with having an unemployed mother, having a mother who worked in the professional and engineering, sales, service, or manufacturing process area was associated with a lower prevalence of low prosocial behaviors, whereas having a mother who worked in the clerical, service, or manufacturing process area was associated with an increased prevalence of emotional problems. Having a mother who worked in a clerical area was associated with a higher prevalence of conduct problems. Higher paternal and maternal educational levels were inversely associated with the prevalence of conduct problems and hyperactivity but were positively associated with low prosocial behaviors. A higher household income was inversely associated with the prevalence of emotional problems, conduct problems, and hyperactivity.

CONCLUSION

Parental occupation, educational levels, and household income may affect children's psychological adjustment in Japan.

HSP90 inhibition overcomes resistance to molecular targeted therapy in BRAFV600E mutant high-grade glioma

PURPOSE

Molecular targeted therapy using BRAF and/or MEK inhibitors has been applied to BRAFV600E mutant high-grade gliomas (HGGs); however, the therapeutic effect is limited by the emergence of drug resistance.

EXPERIMENTAL DESIGN

We established multiple paired BRAFV600E mutant HGG patient-derived xenograft (PDX) models based on tissues collected prior to and at relapse after molecular targeted therapy. Using these models, we dissected treatment resistant mechanisms for molecular targeted therapy and explored therapeutic targets to overcome resistance in BRAFV600E HGG models in vitro and in vivo.

RESULTS

We found that, despite causing no major genetic and epigenetic changes, BRAF and/or MEK inhibitor treatment deregulated multiple negative feedback mechanisms, which led to the re-activation of the MAPK pathway through c-Raf and AKT signaling. This altered oncogenic signaling primarily mediated resistance to molecular targeted therapy in BRAFV600E mutant HGG. To overcome this resistance mechanism, we performed a high-throughput drug screening to identify therapeutic agents that potently induce additive cytotoxicity with BRAF and MEK inhibitors. We discovered that HSP90 inhibition combined with BRAF/MEK inhibition coordinately deactivated the MAPK and AKT/mTOR pathways, and subsequently induced apoptosis via dephosphorylation of GSK3β (Ser9) and inhibition of Bcl-2 family proteins. This mediated potent cytotoxicity in vitro and in vivo in refractory models with acquired resistance to molecular-targeted therapy.

CONCLUSIONS

The combination of an HSP90 inhibitor with BRAF or MEK inhibitors can overcome the limitations of the current therapeutic strategies for BRAFV600E mutant HGG.

Verbal and memory deficits caused by aphasic status epilepticus after resection of a left temporal lobe glioma

Background:

Nonconvulsive status epilepticus (NCSE) is induced by common neurosurgical conditions, for example, trauma, stroke, tumors, and surgical interventions in the brain. The aggressiveness of the treatment for NCSE depends on its neurological prognosis. Aphasic status epilepticus (ASE) is a subtype of focal NCSE without consciousness impairment. The impact of ASE on neurological prognosis is poorly documented. We describe a case of postoperative ASE resulting in verbal and memory deficits.

Case Description:

A 54-year-old, right-handed man with focal impaired awareness seizures underwent partial resection for a left temporal lobe tumor. No neurological deficits were observed immediately after surgery. Three days later, however, a focal to bilateral tonic-clonic seizure (FBTCS) occurred, followed by aphasia. Electroencephalography revealed 1.5 Hz left-sided periodic discharges. He was diagnosed with ASE. Multiple anti-seizure drugs were ineffective for the resolution of the patient’s verbal disturbance. Nine days after the FBTCS, deep sedation with intravenous anesthetics was performed and the ASE stopped. Thereafter, his symptoms gradually improved. However, the prolonged ASE resulted in verbal and memory deficits. Automated hippocampal volumetry revealed an approximate decrease of 20% on the diseased side on magnetic resonance imaging 3 months after surgery.

Conclusion:

Prolonged ASE can induce verbal and memory deficits. Early intervention with intravenous anesthetics is required to obtain a favorable neurological prognosis.

ET-1 Translational research platform for malignant brain tumors

Introduction: The standard therapy for malignant brain tumors includes surgery and combination therapy with radiation and chemotherapy, but to provide individualized treatment based on the biological and molecular genetic background of the tumor, integrate genetic information with various functional data are required. In this study, we present an overview of our integrated approaches for translational research and clinical management. Methods: In glioma, pre-and intra-operative clinical information, including intraoperative genetic diagnosis, and intraoperative rapid immunohistochemistry is obtained, then a multidisciplinary treatment approach is started based on these integrated data. Specimens collected intraoperatively are cryopreserved for future analysis, and primary cultured cells are routinely collected. The cultured cells are transplanted into the brain of immunodeficient mice to establish patient-derived xenograft model (PDX). Genetic screening, such as IDH, TERT, BRAF, H3F3A mutation and MGMT methylation analysis are routinely assessed within a few days after surgery and used as information for integrated diagnosis. In case of PDX establishment or recurrence, we perform whole exon sequencing or comprehensive genomic assessment to identify genetic abnormalities. If genomic alterations for possible molecular targeted therapy are identified, we assess drug sensitivity test in vitro and in vivo, which are utilized for research to develop optimal molecular targeted therapy. The results, such as the therapeutic effects of molecular targeted drugs, are used for clinical applications. Results: Since the platform was established, we have treated a total of 286 patients, including 189 gliomas and 37 central nervous system lymphomas based on the integrated information. We are currently collecting clinical data to examine if this integrated approach could provide clinical benefit.Conclusion: The translational research system for malignant brain tumors plays an important role in the promotion of clinical and basic research.

SPDR-1 HSP90 inhibition overcomes resistant to molecular targeted therapy in BRAFV600E mutant glioblastoma

The BRAFV600E mutation results in the constitutive activation of downstream mitogen activated protein kinase (MAPK) pathway that promotes tumor growth. Recently, molecular targeted therapy using BRAF/MEK inhibitor has been reported for BRAFV600E mutant high-grade glioma, but the therapeutic effect is limited by the emergence of drug resistance. Herein, we established paired BRAFV600E mutant glioblastoma (GBM) patient-derived xenograft (PDX) models, which were derived from tumors at prior to and recurrence after molecular targeted therapy. These PDX models were found to extensively recapitulate the histology, genetic abnormalities, and even the clinical course of the patients. Furthermore, BRAF/MEK inhibitor gradually caused resistance in cell lines derived from specimens that initially responded to molecular targeted therapy. In this study, genomic and epigenomic changes had little effect on the resistance mechanism. On the other hand, we found that hyperactivation of the MAPK pathway through c-Raf and the AKT/mTOR pathway primarily caused resistance to molecular targeted therapy in BRAFV600E mutant GBM. Through a high throughput drug screening, we find that HSP90 inhibitor with BRAF/MEK inhibitor coordinately deactivates MAPK pathway and AKT/mTOR pathway, and mediates potent toxicity in vitro and in vivo in refractory and acquired resistant models. These findings support that this therapeutic approach can overcome the limitation of current molecular targeted therapy in BRAFV600E mutant GBM.

EXTH-73. PROTEASOME INHIBITION EXPOSES SELECTIVE VULNERABILITY IN CENTRAL NERVOUS SYSTEM LYMPHOMA

Central nervous system lymphoma (CNSL), including primary and secondary CNSL, has a poor prognosis despite standard intensive chemotherapy. Since the majority of CNSL tumors are highly dependent on NF-κB signaling pathway for survival, Bruton’s kinase inhibitors, which target upstream in the NF-κB pathway, have demonstrated favorable clinical response in PCNSL patients. However, early recurrence is frequently observed. Therefore, novel therapeutic strategies are required in this progressive CNS disease. To understand the underlying tumor biology and explore a novel therapeutic strategy of CNSL, we previously established a panel of patient-derived xenograft (PDX) models, from both immunocompetent and Epstein-Barr virus (EBV)-positive CNSL patients. We confirmed that these PDX models highly recapitulated the phenotypic and genetic features of patient tumors. Using 19 PDX models, including 17 originally established PDXs, we found that NF-κB pathway related genomic alterations and AKT/mTOR signaling did not correlate with sensitivity to BTK inhibitors. We also found that RelA/p65 dephosphorylation as a biomarker of CNSL cells, which are responding to ibrutinib. Through high-throughput and NF-κB pathway-targeted drug screenings, we discovered that proteasome inhibitors suppressed cell viability across all CNSL models. The therapeutic effect, observed at a lower nanomolar range, was mediated by inhibition of the canonical NF-κB and AKT/mTOR pathways and was reversed by silencing of MYD88/CD79B in immunocompetent CNSL or LMP1 in EBV-positive CNSL. The second-generation proteasome inhibitor marizomib prolonged overall survival in CNSL orthotopic xenograft models through simultaneous suppression of RelA/p65 and AKT/mTOR signaling. Proteasome inhibition deregulated Mcl-1 and mediated caspase-dependent apoptosis, which was further enhanced by Bcl-2 family inhibition. Our results demonstrate the potential of proteasome inhibition as a novel therapeutic strategy in patients with immunocompetent and EBV-positive CNSL.

Severe anaphylaxis caused by intravenous anti-cancer drugs

Background

The incidence and risk factors of severe anaphylaxis by intravenous anti‐cancer drugs are unclear, whereas those of milder reactions have been reported.

Study Design

Electronic medical charts of cancer patients who have undergone intravenous chemotherapy between January 2013 and October 2020 in a university hospital were retrospectively reviewed. Non‐epithelial malignancies were also included in the analysis. "Severe anaphylaxis" was judged using Brown's criteria: typical presentation of anaphylaxis and one or more of hypoxia, shock, and neurologic compromise. (UMIN000042887).

Results

Among 5584 patients (2964 males [53.1%], 2620 females [46.9%], median age 66 years), 88,200 person‐day anti‐cancer drug administrations were performed intravenously, and 27 severe anaphylaxes were observed. The causative drugs included carboplatin (14 cases), paclitaxel (9 cases), and cisplatin, docetaxel, trastuzumab, and cetuximab (1 case each). The person‐based lifetime incidence of severe anaphylaxis for patients who received at least one intravenous chemotherapy was 0.48% (27/5584, 95% confidence interval (CI) 0.30%–0.67%) and the administration‐based incidence was 0.031% (27/88,200, 95% CI 0.019%–0.043%). Among 124 patients who received at least 10 carboplatin administrations, 10 patients experienced carboplatin‐induced severe anaphylaxis (10/124, 8.1%, 95% CI 3.0%–13.1%). Carboplatin caused severe anaphylaxis after at least 9‐min interval since the drip started. Thirteen out of 14 patients experienced carboplatin‐induced severe anaphylaxis within a 75‐day interval from the previous treatment. Paclitaxel infusion caused severe anaphylaxis after a median of 5 min after the first drip of the day at a life‐long incidence of 0.93% (9/968, 95% CI 0.27%–1.59%).

Conclusion

We elucidated the high‐risk settings of chemotherapy‐induced severe anaphylaxis.

Deexcitation Dynamics of Muonic Atoms Revealed by High-Precision Spectroscopy of Electronic K X Rays

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kβ x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

Transient Hyperintensity of the Infant Thyroid Gland on T1-Weighted MR Imaging: Correlation with Postnatal Age, Gestational Age, and Signal Intensity of the Pituitary Gland

BACKGROUND AND PURPOSE

The signal intensity of the thyroid in neonates is high on T1WI. It is affected by gestational and postnatal ages. However, the extent of the influence of these ages is unknown. This study investigated the relationship of signal intensities of the infant thyroid with postnatal and gestational ages and anterior pituitary using 3D gradient-echo T1WI.

MATERIALS AND METHODS

This retrospective study included 183 T1-weighted images from 181 infants. Using a multiple linear regression analysis, we evaluated the effects of postnatal and gestational ages on the thyroid-muscle signal intensity ratio. The relationship between the thyroid and anterior pituitary signal intensities on T1WI and the age of the infants was evaluated.

RESULTS

Multiple linear regression analysis showed that the thyroid signal intensity was affected negatively by postnatal age at examination and positively by gestational age at birth (P < .01 and P = .04, respectively). According to the standardized partial regression coefficients, the influence of postnatal age at examination was stronger than that of gestational age at birth (-0.72 and 0.13, respectively). The thyroid and anterior pituitary signal intensities reached constant values at 12 weeks' postnatal age, and the mean thyroid-anterior pituitary signal intensity ratios were almost 1 throughout the entire period.

CONCLUSIONS

The signal intensity of the infant thyroid on T1WI was more strongly influenced by the postnatal age at examination than the gestational age at birth, and it was almost equal to that of the anterior pituitary.

IDH-Mutant Astrocytoma With Chromosome 19q13 Deletion Manifesting as an Oligodendroglioma-Like Morphology

Partial deletions in chromosomes 1p and 19q are found in a subset of astrocytic tumors; however, it remains unclear how these alterations affect their histological features and prognosis. Herein, we present 3 cases of isocitrate dehydrogenase (IDH)-mutant astrocytoma with chromosome 19q13 deletion. In the first case, the primary tumor harbored an IDH1 mutation with chromosome 1p/19q partial deletions, which covered 19q13 and exhibited a durable initial response to radiotherapy and temozolomide (TMZ) treatment. However, the tumor lost the chromosome 1p/19q partial deletions at recurrence and became resistant to TMZ. Histologically, an oligodendroglioma-like feature was found in the primary tumor but not in the recurrent tumor. Capicua transcriptional repressor (CIC), located on 19q13, was less expressed in the primary tumor but was highly expressed in the recurrent tumor. Similar histological findings were observed in 2 other astrocytic tumors with IDH1 or IDH2 mutations. These tumors also had chromosome 19q13 deletion, including the CIC gene, weakly expressed CIC, and oligodendroglioma-like morphology. These tumors recurred at 6 and 32 months, respectively. These findings suggest that IDH-mutant astrocytoma with chromosome 19q13 partial deletion, including the CIC gene, may induce an oligodendroglioma-like phenotype, but the clinical prognosis may not be similar to that of genetically defined oligodendroglioma.

HGG-51. PAIRED EPITHELIOID GLIOBLASTOMA PATIENT DERIVED XENOGRAFT MODELS WITH/WITHOUT MOLECULAR TARGET THERAPY

Epithelioid glioblastoma (E-GBM) predominantly arises at younger age and promotes dismal prognosis. Because of its rare etiology, pathological and genetical characterization of E-GBM remains elusive. Herein, we report 2 patient-derived E-GBM xenograft (PDX) models from young adult patients (YMG62 and YMG89) with BRAFV600E and TERT promoter mutation. The YMG62 patient received dabrafenib with trametinib, while YMG89 patient received dabrafenib monotherapy after recurrence with Stupp regimen. These molecular target therapies were initially responded, but gradually became resistant (YMG62R and YMG89R) and resulted in lethal. Treatment resistant cells were collected from CSF. These primary cells were propagated at multiple passage in vitro. Paired PDX models were established from initial and recurrent cells. All PDX tumors were preferentially disseminated and negative expression of GFAP, which were recapitulated to the patient characteristics. BRAF and MEK inhibitor moderately suppressed cell viability of YMG62 and YMG89 in vitro. However, BRAF and MEK inhibitor became resistant at recurrence in vitro. Western blotting indicated retained phospho-MEK expression after BRAF/MEK inhibitor treatment in recurrent cells, which implies crucial role of MEK activation for tumor maintenance in BRAFV600E mutant E-GBM. Together, paired E-GBM PDX models with/without molecular target therapy recapitulate patient characteristics, which may contribute to elucidate tumor biology and establish novel therapeutic target in E-GBM.

CBMS-04 Novel xenograft model to clarify tumor progressive mechanism and therapeutic target in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare lymphoma of the central nervous system and has a dismal prognosis despite intensive chemotherapy. Recent genomic analyses have identified recurrent genetic alterations in Primary central nervous system lymphoma (PCNSL). However, lack of clinically representative PCNSL models has diminished our understanding of the pathogenic mechanisms of those genetic events. Here, we established 14 patient-derived orthotopic xenografts (PDOXs). Comprehensive analysis showed that PDOXs faithfully retained the phenotypic, metabolic, and genetic features with 100 % concordance of MYD88 and CD79B mutations present in immuno-competent PCNSL patients. Notably, orthotopic xenograft formation was consistently dependent on deregulated signaling through the RelA/p65-hexokinase 2 (HK-2) axis. MYD88/CD79B mutations and Pin1 activation, or LMP1 and Pin1 activation, converge on the RelA/p65-HK-2 signaling in immunocompetent and EBV-positive PCNSL, respectively. Genetic and pharmacological inhibition of this key signaling axis potently suppressed PCNSL tumor growth in vitro and in vivo. Additionally, our models further offer a platform for predicting clinical chemotherapeutics efficacy. Therefore, our models provide critical insights into pathogenic mechanisms and therapeutic discovery in PCNSL.

CS-03 BRAF V600E mutation mediates FDG-methionine uptake mismatch in polymorphous low-grade neuroepithelial tumor of the young

We present a case of a 14-year old boy with tumor-associated refractory epilepsy. Positron emission tomography imaging demonstrated a region with heterogeneous high 11 C-methionine uptake and a region with homogenous low 18 F- fluorodeoxyglucose uptake within the tumor. Histopathological and genomic analyses confirmed the tumor as BRAF V600E-mutated PLNTY (polymorphous low-grade neuroepithelial tumor of the young). Within the high-methionine-uptake region, we observed increased protein levels of L-type amino acid transporter 1 (LAT1) and constituents of the mitogen-activated protein kinase (MAPK) pathway. We also found that LAT1 expression was linked to BRAF V600E mutation and subsequent activation of MAPK signaling. Pharmacological inhibition of the MAPK pathway suppressed LAT1 expression and cell viability in PLNTY cells. Collectively, our results indicate that BRAF V600E mutation-activated MAPK signaling induces specific metabolic alterations in PLNTY, and may represent an attractive target in the treatment of the disease.

SPDR-01 Paired epithelioid glioblastoma patient-derived xenograft models to evaluate resistant mechanism for molecular target therapy

Epithelioid glioblastoma (E-GBM) arises at younger age, commonly disseminates to cerebrospinal fluid, and results in dismal prognosis. About half of E-GBM harbors BRAF V600E mutation, thus BRAF/MEK inhibitors are expected to be specifically sensitive to E-GBM like other BRAF V600E mutant carcinomas. However, therapeutic effect is limited by the emergence of drug resistance. To overcome this issue, it is crucial to elucidate the treatment resistance mechanisms by clinically representative models. Herein, we establish 2 paired E-GBM patient-derived xenograft (PDX) models from young adult patients (YMG62 and YMG89) with BRAF V600E, TERT promoter mutations and CDKN2A homozygous deletions. The YMG62 patient received dabrafenib with trametinib, while YMG89 patient received dabrafenib monotherapy after recurrence with standard treatment. The YMG62 patient was refractory to combination therapy. The YMG89 patient was initially responded to dabrafenib, but gradually became resistant and the 2 patients died due to CNS dissemination. Paired PDX models were established from tumors prior and after molecular target therapy. All PDXs were formed as CNS dissemination model, which were recapitulated to the patient characteristics. BRAF/MEK inhibitors strongly suppressed cell viability in primary tumor (YMG89P). However, BRAF/MEK inhibitors became resistant in recurrent tumor (YMG89R). YMG62 paired PDXs were resistant to molecular target therapy. Western blotting indicated retained MAPK signaling pathway and/or increased AKT phosphorylation after BRAF/MEK inhibitors treatment in refractory and recurrent cells, which indicates crucial role of re-activation in the MAPK signaling pathway and/or PI3 kinase pathway for tumor maintenance in BRAF V600E mutant E-GBM. We have done high throughput drug screening to identify compounds to overcome resistant to molecular target therapy. Our established E-GBM paired PDX models recapitulate patient characteristics, which may uncover treatment resistant mechanism and novel therapeutic target in E-GBM.

TERT promoter mutation confers favorable prognosis regardless of 1p/19q status in adult diffuse gliomas with IDH1/2 mutations

TERT promoter mutations are commonly associated with 1p/19q codeletion in IDH-mutated gliomas. However, whether these mutations have an impact on patient survival independent of 1p/19q codeletion is unknown. In this study, we investigated the impact of TERT promoter mutations on survival in IDH-mutated glioma cases. Detailed clinical information and molecular status data were collected for a cohort of 560 adult patients with IDH-mutated gliomas. Among these patients, 279 had both TERT promoter mutation and 1p/19q codeletion, while 30 had either TERT promoter mutation (n = 24) or 1p/19q codeletion (n = 6) alone. A univariable Cox proportional hazard analysis for survival using clinical and genetic factors indicated that a Karnofsky performance status score (KPS) of 90 or 100, WHO grade II or III, TERT promoter mutation, 1p/19q codeletion, radiation therapy, and extent of resection (90-100%) were associated with favorable prognosis (p < 0.05). A multivariable Cox regression model revealed that TERT promoter mutation had a significantly favorable prognostic impact (hazard ratio = 0.421, p = 0.049), while 1p/19q codeletion did not have a significant impact (hazard ratio = 0.648, p = 0.349). Analyses incorporating patient clinical and genetic information were further conducted to identify subgroups showing the favorable prognostic impact of TERT promoter mutation. Among the grade II-III glioma patients with a KPS score of 90 or 100, those with IDH-TERT co-mutation and intact 1p/19q (n = 17) showed significantly longer survival than those with IDH mutation, wild-type TERT, and intact 1p/19q (n = 185) (5-year overall survival, 94% and 77%, respectively; p = 0.032). Our results demonstrate that TERT promoter mutation predicts favorable prognosis independent of 1p/19q codeletion in IDH-mutated gliomas. Combined with its adverse effect on survival among IDH-wild glioma cases, the bivalent prognostic impact of TERT promoter mutation may help further refine the molecular diagnosis and prognostication of diffuse gliomas.

A Hyperactive RelA/p65-Hexokinase 2 Signaling Axis Drives Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is an isolated type of lymphoma of the central nervous system and has a dismal prognosis despite intensive chemotherapy. Recent genomic analyses have identified highly recurrent mutations of MYD88 and CD79B in immunocompetent PCNSL, whereas LMP1 activation is commonly observed in Epstein-Barr virus (EBV)-positive PCNSL. However, a lack of clinically representative preclinical models has hampered our understanding of the pathogenic mechanisms by which genetic aberrations drive PCNSL disease phenotypes. Here, we establish a panel of 12 orthotopic, patient-derived xenograft (PDX) models from both immunocompetent and EBV-positive PCNSL and secondary CNSL biopsy specimens. PDXs faithfully retained their phenotypic, metabolic, and genetic features, with 100% concordance of MYD88 and CD79B mutations present in PCNSL in immunocompetent patients. These models revealed a convergent functional dependency upon a deregulated RelA/p65-hexokinase 2 signaling axis, codriven by either mutated MYD88/CD79B or LMP1 with Pin1 overactivation in immunocompetent PCNSL and EBV-positive PCNSL, respectively. Notably, distinct molecular alterations used by immunocompetent and EBV-positive PCNSL converged to deregulate RelA/p65 expression and to drive glycolysis, which is critical for intracerebral tumor progression and FDG-PET imaging characteristics. Genetic and pharmacologic inhibition of this key signaling axis potently suppressed PCNSL growth in vitro and in vivo. These patient-derived models offer a platform for predicting clinical chemotherapeutics efficacy and provide critical insights into PCNSL pathogenic mechanisms, accelerating therapeutic discovery for this aggressive disease. SIGNIFICANCE: A set of clinically relevant CNSL xenografts identifies a hyperactive RelA/p65-hexokinase 2 signaling axis as a driver of progression and potential therapeutic target for treatment and provides a foundational preclinical platform. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/23/5330/F1.large.jpg.

BRAF V600E mutation mediates FDG-methionine uptake mismatch in polymorphous low-grade neuroepithelial tumor of the young

We present a case of a 14-year old boy with tumor-associated refractory epilepsy. Positron emission tomography imaging demonstrated a region with heterogeneous high ¹¹C-methionine uptake and a region with homogenous low ¹⁸F-fluorodeoxyglucose uptake within the tumor. Histopathological and genomic analyses confirmed the tumor as BRAF V600E-mutated polymorphous low-grade neuroepithelial tumor of the young (PLNTY). Within the high-methionine-uptake region, we observed increased protein levels of L-type amino acid transporter 1 (LAT1), a major transporter of methionine; c-Myc; and constituents of the mitogen-activated protein kinase (MAPK) pathway. We also found that LAT1 expression was linked to the BRAF V600E mutation and subsequent activation of MAPK signaling and c-Myc. Pharmacological and genetic inhibition of the MAPK pathway suppressed c-Myc and LAT1 expression in BRAF V600E-mutated PLNTY and glioblastoma cells. The BRAF inhibitor dabrafenib moderately suppressed cell viability in PLNTY. Collectively, our results indicate that BRAF V600E mutation-activated MAPK signaling and downstream c-Myc induces specific metabolic alterations in PLNTY, and may represent an attractive target in the treatment of the disease.

BRAF V600E mutation mediates FDG-methionine uptake mismatch in polymorphous low-grade neuroepithelial tumor of the young

We present a case of a 14-year old boy with tumor-associated refractory epilepsy. Positron emission tomography imaging demonstrated a region with heterogeneous high ¹¹C-methionine uptake and a region with homogenous low ¹⁸F-fluorodeoxyglucose uptake within the tumor. Histopathological and genomic analyses confirmed the tumor as BRAF V600E-mutated polymorphous low-grade neuroepithelial tumor of the young (PLNTY). Within the high-methionine-uptake region, we observed increased protein levels of L-type amino acid transporter 1 (LAT1), a major transporter of methionine; c-Myc; and constituents of the mitogen-activated protein kinase (MAPK) pathway. We also found that LAT1 expression was linked to the BRAF V600E mutation and subsequent activation of MAPK signaling and c-Myc. Pharmacological and genetic inhibition of the MAPK pathway suppressed c-Myc and LAT1 expression in BRAF V600E-mutated PLNTY and glioblastoma cells. The BRAF inhibitor dabrafenib moderately suppressed cell viability in PLNTY. Collectively, our results indicate that BRAF V600E mutation-activated MAPK signaling and downstream c-Myc induces specific metabolic alterations in PLNTY, and may represent an attractive target in the treatment of the disease.

Evaluating the anti-inflammatory and analgesic properties of maropitant: A systematic review and meta-analysis

The neurotransmitter Substance P, and its neurokinin-1 receptor (NK-1R) are involved in the regulation of many pathophysiological processes including emesis, inflammation and nociceptive processing. This review provides a brief summary of the anti-inflammatory and analgesic properties of experimental NK-1R antagonists followed by a systematic review and meta-analysis on maropitant, the only NK-1R antagonist with a label indication for emesis in veterinary patients. There is very limited evidence based information on the putative clinical utilisation of maropitant for pain and inflammation. The aim of this systematic review and meta-analysis was to evaluate published reports on anti-inflammatory, analgesic and anaesthesia-sparing effects of maropitant. Medline, Pubmed, Science direct and Web of Science were searched to identify all published studies on maropitant, followed by a meta-analysis. Fourteen studies with 128 animals receiving maropitant and 127 controls met the inclusion criteria. Overall, maropitant had a significant inhalation anaesthetic-sparing effect (SMD -0.92, 95% CI -1.30, -0.54; P < 0.00001). However, treatment with maropitant had no effect on pain (SMD 0.06, 95% CI -0.37, 0.48; P = 0.80), or leukocyte cell infiltration in different inflammatory conditions (SMD -0.60, 95% CI -1.31, 0.11; P = 0.10). Based on all eligible studies for this review, it can be deduced that maropitant significantly reduced the minimum alveolar concentrations for isoflurane and sevoflurane for many different surgical procedures but it had no clearly proven effect on inflammation and pain.

Characteristics of plasma window with various channel diameters for accelerator applications

Plasma window is a feasible device as an atmosphere-vacuum interface, which can withstand energetic particle beams. It is, however, essential to enlarge the diameter to several tens of millimeters for actual beam passing in the accelerator applications. The pressure separation performance and discharge voltage V current I characteristics should be investigated in detail to design the plasma window for each purpose. Therefore, a cascade arc discharge device with a diameter of up to 20 mm was developed, and its characteristics as a function of diameter were examined. As a result, with an increase in the channel diameter, the discharge pressure that was achieved decreased, whose values were smaller compared with the values by the prediction formula, assuming the viscous gas flow with a constant plasma temperature. It showed that the bulk plasma temperature for the larger discharge channel was low because of the low-current density over the channel. Furthermore, the transition of the V-I slope was observed with an increase in the diameter.

Preliminary study: Measurement of ion beam energy spreads produced by a Penning ionization gauge-type ion source using electromagnets for a mega-electron volt compact ion microbeam system

The energy spreads of ion beams generated from a penning ionization gauge-type ion source with electromagnets were measured using a parallel electrostatic analyzer. The ion source was developed to be installed in a mega-electron volt (MeV) compact ion microbeam system. A gaseous ion beam of expectedly high brightness and narrow energy spread was generated from the ion source to form a microbeam. To produce such an ion beam, a high-density plasma with a small volume was generated using a strong magnetic field in the ion source. The beam energy spread width was of particular importance because it forms an ion microbeam by reducing the chromatic aberration at a focusing lens. In this report, the energy spread was investigated by changing the parameters of the ion source, e.g., extraction voltage, excitation current of electromagnets, vacuum, and anode voltage. The investigation showed that spread widths are influenced by the extraction voltage, vacuum, and anode voltage. The minimum width of ∼5.0 ± 0.1 eV was obtained at a beam energy of 200 eV. This value is acceptable for the MeV compact ion microbeam system.

MPC-01 PROGNOSTIC ROLE OF TERT PROMOTER IMPROVES THE STRATIFICATION OF IDH-MUTATED LOWER GRADE GLIOMA

TERT promoter mutation is associated with favorable prognosis and 1p/19q codeletion in IDH-mutated gliomas. The current diagnostic system, however, did not incorporate this change as a diagnostic marker in this entity. We investigated the value of prognostication incorporating TERT using the Japanese original cohort of 560 IDH-mutated adult gliomas. We collected the information of molecular status of IDH, TERT and 1p/19q and patient clinical data including Karnofsky performance status (KPS). TERT mutation and 1p/19q codeletion were found in 303 and 285 cases, respectively. For the purpose of this study, the patient cohort was divided into four groups by a combination of 1p/19q and TERT status, and the characteristics of 1p/19q intact-TERT mutated group (Astro-TERT group) (n=24) were dissected in light of the differences comparing with 1p/19q intact-TERT wild (Astro-group, n=251) or 1p/19q codeleted-TERT mutated (Oligo-group, n=279) cases. Astro-TERT group with any grade showed intermediate overall survival between the Oligo-group and Astro-group although the survival differences were not statistically significant (median OS: not reached (NR) versus NR, and 106 months, respectively. p>0.05). In grade II-III gliomas, the survival curve of the Astro-TERT group overlapped with that of the Oligo-group while the Astro-TERT group showed short survival as well as the Astro-group. We further conducted subgroup analysis by adjusting KPS in grade II-III tumors. In the subgroup with favorable KPS (90–100) and gradeII-III (n=438), The OS of Astro-TERT group (median NR) was significantly longer survival than that of Astro-group (median NR p=0.032), and was comparable with that of the Oligo-group (median NR, p>0.05). Thus, TERT promoter status provides the additional information for prognostication at least in grade II-III gliomas in the current diagnostic system.

TB-02 NF-KB CANONICAL PATHWAY ACTIVATION DRIVES GLYCOLYSIS AND TUMOR PROGRESSION IN PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA

Recent genomic analyses have identified highly recurrent genetic alterations in PCNSL. However, due to the lack of clinically representative PCNSL preclinical models, the pathogenic mechanisms of these alterations remains largely unknown. Here, we established the largest panel of 12 clinically relevant PCNSL patient-derived orthotopic xenografts retained the histopathologic phenotype, lymphoma expression subtype, copy number alterations and 90% of the non-synonymous mutations of primary tumors, with 100% concordance of MYD88 and CD79B mutations, which are highly recurrent in PCNSL. Patient tumor regression with high-dose methotrexate correlated with in vitro sensitivity to methotrexate in corresponding PCNSL models. By knocking down canonical NF-kB pathway genes, we found that successful orthotopic xenograft formation was dependent on NF-kB canonical pathway activation induced by MYD88 mutation or overexpression of EBV-related LMP1. Metabolically, PCNSL xenografts phenocopied the high 18F-fluorodeoxyglucose uptake observed in patients and demonstrated glycolytic dependence, revealing new potential therapeutic strategies in PCNSL. Collectively, we found NF-kB canonical pathway activation as a crucial driver of PCNSL xenograft progression and found that NF-kB canonical pathway induced an addiction to glycolysis, revealing a novel potential therapeutic strategy. Our PCNSL xenograft panel represents a valuable and reproducible preclinical tool that has the potential to help decipher how genetic and/or epigenetic alterations contributes to lymphomagenesis and tumor maintenance and enhance the development of novel therapeutic strategies in PCNSL.

BT-07 PATIENT DERIVED XENOGRAFT MODELS OF EPITHELIOID GLIOBLASTOMA AND THERAPEUTIC VULNERABILITY IN MOLECULAR TARGET THERAPY

Epithelioid glioblastoma (E-GBM) predominantly arises at younger age and promotes dismal prognosis. Because of its rare etiology, pathological and genetical characterization of E-GBM remains elusive. Herein, we report unique patient-derived E-GBM xenograft (PDX) models from 3 E-GBM patients (2 BRAF^V600E mutant and 1 BRAF^V600E wild-type). Two BRAF mutant E-GBM cells (YMG62 and YMG89) were originated from adolescent and young adult patients and harbored TERT promoter mutation and CDKN2A homozygous deletion, while 1 BRAF^V600E E-GBM cell (YMG64) was from elderly patient and had TERT wild-type. YMG62 and YMG89 could be propagated at multiple passage in vitro, while YMG64 could not be maintained. PDX models were established from YMG62, YMG89, and YMG64. All PDX tumors were preferentially disseminated and negative expression of GFAP, which were recapitulated to the patient characteristics. BRAF and MEK inhibitor mildly suppressed cell viability in vitro. Collectively, E-GBM PDX models recapitulate patient characteristics, which may be helpful to elucidate tumor biology and establish novel therapeutic target in E-GBM.

TB-04 TERT PROMOTER MUTATION AS A SUSCEPTIBLE MOLECULAR MARKER OF BCNU LOCAL THERAPY

INTRODUCTION

Alkylating agents, including Temozolomide (TMZ) and CCNU (ACNU) have been widely accepted as a standard treatment in malignant gliomas. Several studies also demonstrated that BCNU wafer placement extended survival in glioblastoma patients. However, little study demonstrated gene-specific efficacy of BCNU local therapy in malignant gliomas. Herein, we investigated BCNU sensitivity for patient-derived primary cultured glioma cells.

MATERIALS AND METHODS

From January 2017 to July 2019, 58 gliomas (grade III, IV) were tested genomic analysis and ATP-based cell viability after BCNU treatment. IDH1/2 mutation and TERT promoter mutation status was determined by Sanger sequencing. MGMT methylation status were evaluated by methylation specific PCR.

RESULTS

Of 58 cases,10 cases (17.2%) and 32 (55.2%) cases harbored IDH1/2 mutation and TERT mutation (C228T, C250T), respectively. Among them, co-mutation was identified in 5/58 cases (8.6%). MGMT was methylated in 17/58 cases (29.3%). Interestingly, the presence of TERT promoter mutation was positively correlated with BCNU sensitivity, particularly in IDH1/2 wild-type tumors (p<0.05). In contrast, there was no significant relationship between TMZ sensitivity and IDH mutation/MGMT methylation status.

CONCLUSION

Although sample size is small, our results imply TERT promoter mutations might be a predictive molecular marker for BCNU sensitivity in malignant gliomas. Since TERT mutations are located at two hot spot loci (C228T and C250T), vast majority of TERT promoter mutations can be evaluated during surgery, which may contribute tailored therapeutic strategy in malignant gliomas.

Determination of Docosahexaenoic Acid and n-3 Fatty Acids in Refined Fish Oils by H-NMR Spectroscopy: IUPAC Interlaboratory Study

A high-resolution proton nuclear magnetic resonance (NMR) method for determining the concentration (mg/g) of docosahexaenoic acid (DHA), the molar proportion (mol%) of DHA, and the molar proportion of total n-3 fatty acids in fish oils was validated by an IUPAC interlaboratory study (the Commission VI-6 on Oils, Fats, and Derivatives WG 3/98). Thirteen laboratories from 5 countries tested 6 pairs of blind duplicate fish oils: a refined tuna oil, 2 extracted tuna oils, an extracted bonito oil, an extracted salmon oil, and an extracted sardine oil ranging from 9 to 30 mol% DHA and from 20 to 35 mol% n-3 fatty acids. Before 1D-proton NMR measurements with 300–500 MHz instruments, oil samples were weighed and diluted with deuterochloroform solution containing ethylene glycol dimethyl ether as internal standard. To achieve precise performance, a detailed procedure for signal area measurement was described in the protocol, and all participants were instructed about the critical importance of following the protocol. Statistical performances with invalid and outlier data removed were as follows: repeatability relative standard deviations (RSDr) ranged from 0.91 to 2.62% and reproducibility relative standard deviation (RSDR) ranged from 1.73 to 4.27% for DHA concentration (mg/g); RSDr ranged from 0.39 to 2.06%, and RSDR ranged from 0.59 to 3.46% for mol% DHA; RSDr ranged from 0.23 to 0.90% and RSDR ranged from 0.85 to 2.01% for mol% total n-3 fatty acids. The method is expected to be recommended by IUPAC.

PATH-37. PROGNOSTIC ROLE OF TERT PROMOTER MUTATIONS IMPROVES THE STRATIFICATION OF IDH-MUTATED LOWER GRADE GLIOMA

TERT promoter mutation is associated with 1p/19q codeletion and favorable prognosis in IDH-mutated gliomas. Prognostic and diagnostic significance of TERT promoter mutation is well-recognized in IDH-wildtype glioblastomas, but not in IDH-mutated gliomas. We investigated prognostic efficacy of TERT mutation in a cohort of 560 Japanese IDH-mutated adult gliomas. The molecular status of IDH, TERT and 1p/19q and patient clinical data including Karnofsky performance status (KPS) were collected in all cases. TERT mutations and 1p/19q codeletions were found in 303 and 285 cases, respectively. The patient cohort was divided into four groups by a combination of the 1p/19q and TERT status. The characteristics of 1p/19q intact-TERT mutated group (Astro-TERT group, n=24) were compared with those of 1p/19q intact-TERT wild (Astro-group, n=251) or 1p/19q codeleted-TERT mutated (Oligo-group, n=279) cases. Astro-TERT group with any grade showed intermediate overall survival between the Oligo-group and Astro-group although the survival differences were not statistically significant (median overall survival (OS) not reached (NR) versus NR, and 106 months, respectively. p >0.05). We further conducted subgroup analysis by adjusting KPS and WHO grade as Cox regression analysis for survival indicated the unfavorable survival impact of KPS < 90 and WHO grade IV. In the subgroup with favorable KPS (90–100) and grade II-III (n=438), The OS of Astro-TERT group (median NR) was significantly longer survival than that of Astro-group (median 120.2 months, p=0.032), and was comparable with that of the Oligo-group (median NR, p >0.05). On the other hand, OS of none of the molecular groups significantly differ in poorer KPS subgroups (p >0.05). In grade IV tumors, the OS of the Astro-TERT group (NR) was comparable with that of Astro-group (29 months, p=0.19) rather than Oligo-group (NR, p=0.051). Thus, TERT promoter status provides a valuable prognostic information for IDH-mutated grade II-III gliomas in the current molecular diagnostic system.

P6578Development of the novel program to diagnose atrial fibrillation using automated blood pressure monitor

Background

Atrial fibrillation (AF) is often asymptomatic and contributes to an increased risk of strokes. The development of proper screening device of AF is unmet medical needs worldwide. Recently, we had reported that multiple measurements using Omron automated blood pressure (BP) monitor with irregular heartbeat detection showed high sensitivity and specificity for AF detection in general cardiac patients, however, this method had limitations in discriminating between AF and other arrhythmias.

Purpose

The aim of this study is to develop a novel program that can accurately diagnose AF by discriminating it from other arrhythmias using the pressure pulse waveform data outputted from Omron automated BP monitor.

Methods

In our previous clinical research, BP measurements were performed 3 times each for 303 general cardiac patients (mean age: 72.2 years, 69.8% male) with recording the real-time single lead ECG, and a total of 909 pressure pulse waveforms were obtained. Among them, 840 pressure pulse waveforms from 280 patients (include 40 AF patients) used for further analysis. We developed a program to analyze and visualize uniquely the characteristics of AF waveform through the autocorrelation-based waveform processing system produced by Melody International Ltd, Kagawa, Japan. All visualized results were judged and classified into Sinus, Non-AF and AF by two individuals blinded to the results. For each patient who obtained 3 results, a two by two contingency table was created and sensitivity, specificity, and accuracy for diagnosing AF were calculated.

Results

Among 840 pressure pulse waveforms, only 21 (2 Sinus and 19 Non-AF) out of 720 Sinus and Non-AF waveforms were judged as AF, and 7 out of 120 AF waveforms were judged as Non-AF. None of AF waveforms was absolutely misjudged as Sinus. In analysis for each patient, when one or more AF judgements were found in 3 waveforms, the diagnosis of AF has sensitivity and specificity of 100% and 95.8%, respectively. When two or more AF judgements were found in 3 waveforms, the diagnosis of AF has sensitivity and specificity of 100% and 97.9%, respectively. In this rule, the diagnostic accuracy of AF reached up to 98.8%, and no sinus patients were misjudged as AF.

Conclusion

The novel program, which applied autocorrelation methods uniquely to analysis of the pressure pulse waveforms recorded by automated BP monitor, showed high sensitivity and high specificity for AF diagnosis in general cardiac patients. This program is expected to be useful for early diagnosis for asymptomatic AF patients.

Acknowledgement/Funding

The present research is supported by a grant through the SCOPE from the Ministry of Internal Affairs and Communications, Japan.

P13.01 TERTpromoter methylation is significantly associated withTERTupregulation and tumor progression in pituitary adenomas

BACKGROUND

Activation of telomerase plays a critical role in tumor development. Somatic alterations in the promoter of the telomerase reverse transcriptase (TERT) gene are a major mechanism of upregulating telomerase. Several mechanisms have been associated with TERT abnormalities, including TERT promoter mutations or methylation. Mutations in the TERT promoter have been observed in a subset of brain tumors, especially in adult gliomas. In pituitary adenomas (PAs), however, TERT abnormalities are not fully understood. The present study aimed to investigate not only mutational but also methylation status changes in the TERT promoter in PAs and to analyze their correlations with clinical variables.

MATERIAL AND METHODS

We retrospectively studied 70 PAs consisting of 53 primary and 17 recurrent samples. Clinical data, including age at surgery, sex, tumor size, tumor subtype, resection rate, presence or absence of postoperative irradiation, and progression-free survival (PFS), were obtained from medical records. First, we investigated TERT promoter hotspot mutations via Sanger sequencing. Next, we quantified the methylation status of the TERT promoter using methylation-sensitive high-resolution melting analysis (MS-HRM). Finally, we investigated TERT mRNA expression levels using real-time quantitative PCR. Fisher’s exact test was applied to evaluate the statistical significance between TERT promoter methylation status and tumor recurrence. PFS was calculated using Kaplan-Meier estimates and compared between methylated with ummethylated PAs with the log-rank test. The correlation between TERT promoter methylation status and mRNA levels was analyzed with the Mann-Whitney U-test. PFS was analyzed using multivariate analysis with the Cox proportional hazards model and included the following variables: age, sex, tumor size, tumor subtype, resection rate, radiation therapy, and methylation status.

RESULTS

TERT promoter hotspot mutations were not observed in any PA sample. Nineteen percent of PAs exhibitedTERT promoter methylation, which was significantly predominant in recurrent PA samples. PFS was significantly shorter in the methylated cases than in the unmethylated cases. Higher TERT expression levels were correlated with methylation status.

CONCLUSION

We found that TERT promoter methylation upregulated TERT expression and was associated with shorter PFS in PAs. Our results suggest thatTERT promoter methylation may be a potential biomarker for predicting tumor recurrence in PAs.

Preterm birth is associated with higher prevalence of wheeze and asthma in a selected population of Japanese children aged three years

BACKGROUND

The present cross-sectional study investigated the associations between low birthweight (LBW), high birthweight, preterm birth (PTB), postterm birth, small for gestational age (SGA), and large for gestational age (LGA) and the prevalence of wheeze and asthma in Japanese children aged three years (age range, 33-54 months; mean age, 38.7 months).

METHODS

Study subjects were 6364 children. A questionnaire was used to collect all data. Wheeze and asthma were defined according to the criteria of the International Study of Asthma and Allergies in Childhood.

RESULTS

The prevalence values of wheeze and asthma were 19.5% and 7.7%, respectively. Of the 6364 subjects, 8.8% were classified as LBW (<2500g), 90.4% as normal birthweight, 0.8% as high birthweight (≥4000g), 4.8% as PTB (<37 weeks), 94.8% as term birth, 0.4% as postterm birth (≥42 weeks), 7.8% as SGA (<10th percentile), 82.5% as appropriate for gestational age, and 9.7% as LGA (>90th percentile). Compared with term birth, PTB was independently positively associated with wheeze and asthma: the adjusted ORs (95% CI) were 1.47 (1.11-1.92) and 1.52 (1.02-2.20), respectively. An independent positive association was shown between PTB and wheeze only in boys; the interaction between PTB and sex was significant. Such an interaction between PTB and sex was not seen for asthma. No evident associations were observed between LBW, high birthweight, postterm birth, SGA, or LGA and wheeze or asthma.

CONCLUSIONS

This is the first study in Japan to show that PTB, but not LBW or SGA, was significantly positively associated with childhood wheeze and asthma.

PI3K/AKT/mTOR Pathway Alterations Promote Malignant Progression and Xenograft Formation in Oligodendroglial Tumors

PURPOSE

Oligodendroglioma has a relatively favorable prognosis, however, often undergoes malignant progression. We hypothesized that preclinical models of oligodendroglioma could facilitate identification of therapeutic targets in progressive oligodendroglioma. We established multiple oligodendroglioma xenografts to determine if the PI3K/AKT/mTOR signaling pathway drives tumor progression.

EXPERIMENTAL DESIGN

Two anatomically distinct tumor samples from a patient who developed progressive anaplastic oligodendroglioma (AOD) were collected for orthotopic transplantation in mice. We additionally implanted 13 tumors to investigate the relationship between PI3K/AKT/mTOR pathway alterations and oligodendroglioma xenograft formation. Pharmacologic vulnerabilities were tested in newly developed AOD models in vitro and in vivo.

RESULTS

A specimen from the tumor site that subsequently manifested rapid clinical progression contained a PIK3CA mutation E542K, and yielded propagating xenografts that retained the OD/AOD-defining genomic alterations (IDH1 ^R132H and 1p/19q codeletion) and PIK3CA ^E542K, and displayed characteristic sensitivity to alkylating chemotherapeutic agents. In contrast, a xenograft did not engraft from the region that was clinically stable and had wild-type PIK3CA. In our panel of OD/AOD xenografts, the presence of activating mutations in the PI3K/AKT/mTOR pathway was consistently associated with xenograft establishment (6/6, 100%). OD/AOD that failed to generate xenografts did not have activating PI3K/AKT/mTOR alterations (0/9, P < 0.0001). Importantly, mutant PIK3CA oligodendroglioma xenografts were vulnerable to PI3K/AKT/mTOR pathway inhibitors in vitro and in vivo-evidence that mutant PIK3CA is a tumorigenic driver in oligodendroglioma.

CONCLUSIONS

Activation of the PI3K/AKT/mTOR pathway is an oncogenic driver and is associated with xenograft formation in oligodendrogliomas. These findings have implications for therapeutic targeting of PI3K/AKT/mTOR pathway activation in progressive oligodendrogliomas.

New precise measurements of muonium hyperfine structure at J-PARC MUSE

High precision measurements of the ground state hyperfine structure (HFS) of muonium is a stringent tool for testing bound-state quantum electrodynamics (QED) theory, determining fundamental constants of the muon magnetic moment and mass, and searches for new physics. Muonium is the most suitable system to test QED because both theoretical and experimental values can be precisely determined. Previous measurements were performed decades ago at LAMPF with uncertainties mostly dominated by statistical errors. At the J-PARC Muon Science Facility (MUSE), the MuSEUM collaboration is planning complementary measurements of muonium HFS both at zero and high magnetic field. The new high-intensity muon beam that will soon be available at H-Line will provide an opportunity to improve the precision of these measurements by one order of magnitude. An overview of the different aspects of these new muonium HFS measurements, the current status of the preparation for high-field measurements, and the latest results at zero field are presented.

Novel, improved grading system(s) for IDH-mutant astrocytic gliomas

According to the 2016 World Health Organization Classification of Tumors of the Central Nervous System (2016 CNS WHO), IDH-mutant astrocytic gliomas comprised WHO grade II diffuse astrocytoma, IDH-mutant (AII_IDHmut), WHO grade III anaplastic astrocytoma, IDH-mutant (AAIII_IDHmut), and WHO grade IV glioblastoma, IDH-mutant (GBM_IDHmut). Notably, IDH gene status has been made the major criterion for classification while the manner of grading has remained unchanged: it is based on histological criteria that arose from studies which antedated knowledge of the importance of IDH status in diffuse astrocytic tumor prognostic assessment. Several studies have now demonstrated that the anticipated differences in survival between the newly defined AII_IDHmut and AAIII_IDHmut have lost their significance. In contrast, GBM_IDHmut still exhibits a significantly worse outcome than its lower grade IDH-mutant counterparts. To address the problem of establishing prognostically significant grading for IDH-mutant astrocytic gliomas in the IDH era, we undertook a comprehensive study that included assessment of histological and genetic approaches to prognosis in these tumors. A discovery cohort of 211 IDH-mutant astrocytic gliomas with an extended observation was subjected to histological review, image analysis, and DNA methylation studies. Tumor group-specific methylation profiles and copy number variation (CNV) profiles were established for all gliomas. Algorithms for automated CNV analysis were developed. All tumors exhibiting 1p/19q codeletion were excluded from the series. We developed algorithms for grading, based on molecular, morphological and clinical data. Performance of these algorithms was compared with that of WHO grading. Three independent cohorts of 108, 154 and 224 IDH-mutant astrocytic gliomas were used to validate this approach. In the discovery cohort several molecular and clinical parameters were of prognostic relevance. Most relevant for overall survival (OS) was CDKN2A/B homozygous deletion. Other parameters with major influence were necrosis and the total number of CNV. Proliferation as assessed by mitotic count, which is a key parameter in 2016 CNS WHO grading, was of only minor influence. Employing the parameters most relevant for OS in our discovery set, we developed two models for grading these tumors. These models performed significantly better than WHO grading in both the discovery and the validation sets. Our novel algorithms for grading IDH-mutant astrocytic gliomas overcome the challenges caused by introduction of IDH status into the WHO classification of diffuse astrocytic tumors. We propose that these revised approaches be used for grading of these tumors and incorporated into future WHO criteria.

A Case of Suspicious Gangliocytoma with Heterogeneously Distributed Lesions in the Thalamus and Basal Ganglia

We report a case of a 24-year-old woman who presented with an uncomfortable feeling in her right foot with a 6-month history of slight weakness in her right hand. Neuroimaging demonstrated irregular shaped lesions in the left thalamus and basal ganglia in addition to spotty lesions in the contralateral thalamus. The MRI showed high-intensity signals on T2-weighted, fluid-attenuated inversion recovery, and diffusion-weighted images. The lesions demonstrated low-intensity signaling on T1-weighted images and were slightly enhanced with gadolinium. Other examinations including positron emission tomography, MR spectroscopy, and laboratory tests did not reveal any specific information regarding the lesions. The biopsied specimens, from the left basal ganglia, revealed proliferation of dysplastic neuronal cells without any neoplastic glial elements; thus, gangliocytoma (WHO grade I) was the most likely diagnosis. The patient was further observed based on this diagnosis of suspicious gangliocytoma, and the follow-up MRI, performed a year after the biopsy, revealed that the disease was stable. To our knowledge, gangliocytoma in the thalamus and basal ganglia have not been reported. Additionally, the findings of the magnetic resonance imaging (MRI) in this case were unique and different from those previously reported in cases of gangliocytoma. The authors report this unique case and discuss the radiological, pathological, and genetic findings.