Pemetrexed for Recurrent Primary Central Nervous System Lymphoma in the Elderly: Results of a Retrospective Study.

Aim: Primary central nervous system lymphoma (PCNSL) is an aggressive, destructive, and rapidly progressive malignant brain tumor. Although aggressive therapies were studied trying to increase the median survival of PCNSL, the high relapse rate of PCNSL is still a big problem for the oncology medicine. A retrospective study was made to evaluate the efficacy and safety of pemetrexed in the treatment of patients with recurrent PCNSL. Methods: Twenty-three confirmed recurrent PCNSL patients were selected during April 2012 and August 2016. Dexamethasone, B12, and folic acid were used to produce the toxicity related to pemetrexed. The patients were intravenously given pemetrexed (900 mg/m2) every three weeks for 6 weeks. Results: After the treatment, 7 patients were in complete remission, 6 patients in partial remission, 4 patients in stable condition, and 6 patients in progression. There were 56.5% and 73.9% in the overall response rate and the disease control rate, respectively. The median overall survival (OS) was 6.6 months (95% CI, 4.6-8.6). Conclusion: This study has been the first time to evaluate the safety and effectiveness of pemetrexed on elderly recurrent PCNSL patients. Results demonstrate that using high-dose pemetrexed might be a feasible and effective treatment for recurrent PCNSL in the elderly, and clinical trials should be conducted to further confirm it.

High-dose methotrexate and rituximab induction regimen in immunocompetent patients with primary CNS lymphoma: a retrospective single-center study of survival predictors.

PURPOSE: Primary Central Nervous System Lymphoma (PCNSL) is an aggressive tumor that is confined to the CNS. Although the provision of high-dose methotrexate (HD-MTX) has remarkably improved outcomes in PCNSL patients, the optimal treatment regimens and standard MTX dose for induction therapy have been largely controversial. Herein, we sought to explore the impact of adjuvant rituximab and different dosages of induction HD-MTX on survival outcomes of immunocompetent patients with PCNSL. METHODS: In this study, we examined patients with PCNSL treated at a single NCI-designated comprehensive cancer center to evaluate their survival outcomes. We conducted a retrospective analysis of 51 immunocompetent patients with PCNSL who received their induction chemotherapy at the University of Alabama at Birmingham (UAB) between 2001 and 2019. Only adult patients with a confirmed diagnosis of PCNSL who had either HD-MTX alone or in combination with rituximab were included. Patients' demographics, clinical characteristics, and survival data were collected and analyzed. RESULTS: There is no significant difference in survival among patients who received MTX alone versus MTX plus rituximab (HR = 0.996 (95% CI: 0.398-2.493), p = 0.994). Lower doses of MTX were associated with worse survival outcomes (HR = 0.680 (95% CI: 0.530-0.872), p = 0.002); however, this difference in survival was not significant when adjusted to age (HR = 0.797 (95% CI: 0.584-1.088), p = 0.153). CONCLUSION: Our experience challenges the role of rituximab in PCNSL during induction therapy. Our study also highlights the shorter survival in elderly patients with PCNSL which can be related, to some extent, to the relatively lower doses of HD-MTX. There is an unmet need to establish a consensus on the most effective upfront regimen in PCNSL through prospective studies.

Efficacy of Boron Neutron Capture Therapy in Primary Central Nervous System Lymphoma: In Vitro and In Vivo Evaluation.

BACKGROUND: Boron neutron capture therapy (BNCT) is a nuclear reaction-based tumor cell-selective particle irradiation method. High-dose methotrexate and whole-brain radiation therapy (WBRT) are the recommended treatments for primary central nervous system lymphoma (PCNSL). This tumor responds well to initial treatment but relapses even after successful treatment, and the prognosis is poor as there is no safe and effective treatment for relapse. In this study, we aimed to conduct basic research to explore the possibility of using BNCT as a treatment for PCNSL. METHODS: The boron concentration in human lymphoma cells was measured. Subsequently, neutron irradiation experiments on lymphoma cells were conducted. A mouse central nervous system (CNS) lymphoma model was created to evaluate the biodistribution of boron after the administration of borono-phenylalanine as a capture agent. In the neutron irradiation study of a mouse PCNSL model, the therapeutic effect of BNCT on PCNSL was evaluated in terms of survival. RESULTS: The boron uptake capability of human lymphoma cells was sufficiently high both in vitro and in vivo. In the neutron irradiation study, the BNCT group showed a higher cell killing effect and prolonged survival compared with the control group. CONCLUSIONS: A new therapeutic approach for PCNSL is urgently required, and BNCT may be a promising treatment for PCNSL. The results of this study, including those of neutron irradiation, suggest success in the conduct of future clinical trials to explore the possibility of BNCT as a new treatment option for PCNSL.

Protective Effect of Resveratrol against Glioblastoma: A Review.

BACKGROUND: One of the most common tumors of the central nervous system is Glioblastoma (GBM). OBJECTIVE: There is not still an appropriate cure for this malignant tumor. Plant-derived natural products have demonstrated great potential in cancer therapy, and Resveratrol (Res) is among them. Therefore, the current study focused on the protective effect of resveratrol against glioblastoma and its underlying mechanism. METHODS: PubMed, Medline, Scopus, Web of Science, and Google Scholar were searched by using the following keywords: Resveratrol, Glioblastoma, Brain tumor, Cancer therapy, Medicinal herbs to July 2020. RESULTS: Res is a non-flavonoid polyphenol responsible for the protection of plants against pathogen attacks. Res has multiple pharmacological effects, including antioxidant, anti-inflammatory, anti-diabetic, and anti-tumor. Res is capable of penetration into the blood-brain barrier, making it suitable for brain tumor therapy. Besides, Res targets various molecular signaling pathways in cancer therapy. CONCLUSION: In the present review, it was found that Res administration is beneficial in GBM therapy by inhibition of proliferation, viability, and migration via modulation of molecular pathways.

Diagnostic Yield of Body CT and Whole-Body FDG PET/CT for Initial Systemic Staging in Patients With Suspected Primary CNS Lymphoma: A Systematic Review and Meta-Analysis.

BACKGROUND. Several guidelines recommend body imaging for the initial work-up of patients with suspected primary CNS lymphoma, to exclude subclinical systemic involvement. However, to our knowledge, the diagnostic yield of body CT (contrast-enhanced CT of the chest, abdomen, and pelvis) and whole-body FDG PET/CT for the evaluation of subclinical systemic lymphoma has not yet been systematically evaluated. OBJECTIVE. The purpose of this study was to investigate and compare the diagnostic yield of body CT and whole-body FDG PET/CT in detecting subclinical systemic lymphoma in patients with suspected primary CNS lymphoma. EVIDENCE ACQUISITION. A systematic search of the MEDLINE and EMBASE databases through July 5, 2020, was conducted to identify studies evaluating the diagnostic yield of body CT or whole-body FDG PET/CT in detecting subclinical systemic lymphoma in patients with suspected primary CNS lymphoma. Pooled estimates of the diagnostic yield of both imaging modalities were calculated using the DerSimonian and Laird random-effects model. The false referral rate and the rate of incidental secondary malignancy were also pooled. EVIDENCE SYNTHESIS. Nine original articles on studies evaluating a total of 1040 patients were included. In detecting subclinical systemic lymphoma, the pooled diagnostic yields of body CT and whole-body FDG PET/CT were 2.5% (95% CI, 1.5-3.9%) and 4.9% (95% CI, 2.8-8.5%), respectively. In the subgroup analysis, the diagnostic yield of whole-body FDG PET/CT was significantly higher than that of body CT (p = .03). Four studies reported changes in the management plan: the R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone) regimen with or without radiation therapy was added if extracranial lymphoma involvement was detected by body CT or whole-body FDG PET/CT. The pooled false referral rate of whole-body FDG PET/CT was 5.3% (95% CI, 2.2-12.0%). The pooled rate of incidental secondary malignancy detected on whole-body FDG PET/CT was 3.1% (95% CI, 1.7-5.6%). CONCLUSION. Body imaging should be used in the initial workup of patients with suspected primary CNS lymphoma, to exclude systemic involvement. Whole-body FDG PET/CT may be a better alternative to body CT. CLINICAL IMPACT. Our results support current National Comprehensive Cancer Network guidelines for the use of body imaging to exclude subclinical systemic involvement in patients with suspected primary CNS lymphoma.

Clinical Follow-Up of Patients with Neurocutaneous Melanosis in a Tertiary Center; Proposed Modification in Diagnostic Criteria.

INTRODUCTION: Neurocutaneous melanosis (NCM) is a rare congenital syndrome. Except for some retrospective studies, information on clinical follow-up and management of these patients are limited. This study aimed to review our experience on diagnostic protocol and clinical follow-up of patients with NCM in a referral children's hospital in Iran. METHODS: Between 2012 and 2019, eight patients with NCM were consecutively managed in our center. Brain magnetic resonance imaging and cutaneous biopsy were done in all patients at diagnosis. Follow-up surveillance and characteristics of the disease are described. RESULTS: The mean follow-up period was 25.75 ± 13.81 months, and 75% of patients were male. Most magnetic resonance imaging findings were hypersignal lesions in the temporal lobe (75%), cerebellum (62.5%), brainstem (50%), and thalamus (12.5%). Dandy-Walker syndrome was found in 4 patients (50%), and shunt-dependent hydrocephalus was found in 3 patients (37.5%). Cutaneous malignant melanoma and malignant involvement of the central nervous system were found in 2 (25%) and 3 cases (37.5%), respectively. The mortality rate was 37.5%. CONCLUSIONS: There are no specific guidelines for management of NCM due to the rarity of the disease. This study proposed modifications in diagnostic criteria, as well as recommendations for follow-up surveillance.

Erinacerins, Novel Glioma Inhibitors from Hericium erinaceus, Induce Apoptosis of U87 Cells through Bax/Capase-2 Pathway.

BACKGROUND: Glioma is the most common tumor of the central nervous system. Hericium erinaceus, which has been reported to have a variety of pharmacological activities, is a widely used Traditional Chinese Medicine (TCM), and also a kind of delicious food accepted by the public. METHODS AND RESULTS: In this study, two new natural products, compounds 1 and 2, were isolated and identified from Hericium erinaceus. They were named erinacerin O and erinacerin P, respectively, after the structural identification, and their effects on human glioma cell line U87 were evaluated. Erinacerin P (2) exhibited obvious cytotoxicity on human glioma cell line U87. The IC50 value of 2 was 19.32µg/mL. The results showed that the apoptosis of U87 cells treated with 2 increased and the morphology of U87 cells altered significantly. Flow cytometry experiment showed that 2 could significantly increase the apoptosis rate of U87 cells and reduce DNA replication. Western blot results suggested the Bax/capase-3 pathway was involved in the U87 cell apoptosis induced by 2. CONCLUSION: Erinacerin O and Erinacerin P are novel compounds obtained from Hericium erinaceus and Erinacerin P could be a potential novel glioma inhibitor.

Ibrutinib in primary central nervous system diffuse large B-cell lymphoma.

The standard regimen for the treatment of newly diagnosed primary CNS lymphoma (PCNSL) remains regimens that contain high-dose methotrexate (MTX). While these regimens can provide control for some patients, there is a dearth of options for the treatment of patients with PCNSL who cannot tolerate MTX-containing regimens, or whose cancers are refractory to MTX. In this article, we review a promising new option; ibrutinib, a Bruton tyrosine kinase inhibitor, for patients with relapsed and refractory PCNSL.

Immunohistochemistry for c-myc and bcl-2 overexpression improves risk stratification in primary central nervous system lymphoma.

Overexpression of bcl-2 and c-myc are defining features of double-expressor-lymphoma (DEL) but may also occur separately in patients with primary central nervous system lymphoma (PCNSL). Despite all progress in optimizing treatment regimen, there is lack of sufficient risk stratification models. Here, we first describe the relationship between DEL biology, the National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI), treatment response, disease progression, and mortality in PCNSL. In this study, we determined c-myc and bcl-2 status immunohistochemically in samples of 48 patients with newly diagnosed PCNSL and followed these patients for a median interval of 6.2 years. Twelve, 18, and 17 patients harbored none, one, or both DEL features. Corresponding overall response rates after first-line therapy were strongly associated with DEL biology (100%, 42%, and 44% in patients with 0, 1, or 2 DEL features). Patients with one or both DEL features had a 5-fold and 13-fold higher 5-year risk of progression and/or death than patients without DEL features. These associations prevailed after adjusting for the NCCN-IPI. DEL improved the discriminatory capability of the NCCN-IPI (P = .0001). Furthermore, we could show that addition of DEL biology to the NCCN-IPI significantly improved the score's discriminatory potential both toward progression-free survival (increase in Harell's c = 0.15, P = .005) and overall survival (increase in Harell's c = 0.11, P = .029). In conclusion, DEL biology is a strong and simple-to-use predictor of adverse outcome in PCNSL. Addition of DEL to the NCCN-IPI improves its prognostic potential. Disease progression from PCNSL harboring both DEL features is invariably fatal. This defines a novel PCNSL patient subset with a great unmet need for improved therapy.

Herbal Medicine for Glioblastoma: Current and Future Prospects.

BACKGROUND: Glioblastoma is one of the most aggressive and devastating tumours of the central nervous system with short survival time. Glioblastoma usually shows fast cell proliferation and invasion of normal brain tissue causing poor prognosis. The present standard of care in patients with glioblastoma includes surgery followed by radiotherapy and temozolomide (TMZ) based chemotherapy. Unfortunately, these approaches are not sufficient to lead a favorable prognosis and survival rates. As the current approaches do not provide a long-term benefit in those patients, new alternative treatments including natural compounds, have drawn attention. Due to their natural origin, they are associated with minimum cellular toxicity towards normal cells and it has become one of the most attractive approaches to treat tumours by natural compounds or phytochemicals. OBJECTIVE: In the present review, the role of natural compounds or phytochemicals in the treatment of glioblastoma describing their efficacy on various aspects of glioblastoma pathophysiology such as cell proliferation, apoptosis, cell cycle regulation, cellular signaling pathways, chemoresistance and their role in combinatorial therapeutic approaches was described. METHODS: Peer-reviewed literature was extracted using Pubmed, EMBASE Ovid and Google Scholar to be reviewed in the present article. CONCLUSION: Preclinical data available in the literature suggest that phytochemicals hold immense potential to be translated into treatment modalities. However, further clinical studies with conclusive results are required to implement phytochemicals in treatment modalities.

Therapeutic management of neuro-oncologic patients - potential relevance of CSF liquid biopsy.

Background: In the era of precision medicine, cancer treatment is increasingly tailored according to tumor-specific genomic alterations. The analysis of tumor-derived circulating nucleic acids in cerebrospinal fluid (CSF) by next generation sequencing (NGS) may facilitate precision medicine in the field of CNS cancer. We therefore evaluated whether NGS from CSF of neuro-oncologic patients reliably detects tumor-specific genomic alterations and whether this may help to guide the management of patients with CNS cancer in clinical practice. Patient and methods: CSF samples from 27 patients with various primary and secondary CNS malignancies were collected and evaluated by NGS using a targeted, amplicon-based NGS-panel (Oncomine Focus Assay). All cases were discussed within the framework of a molecular tumor board at the Comprehensive Cancer Center Munich. Results: NGS was technically successful in 23/27 patients (85%). Genomic alterations were detectable in 20/27 patients (74%), 11/27 (40%) of which were potentially actionable. After discussion in the MTB, a change of therapeutic management was recommended in 7/27 (26%) of the cases. However, due to rapid clinical progression, only 4/27 (15%) of the patients were treated according to the recommendation. In a subset of patients (6/27, 22%), a high number of mutations of unknown significance suggestive of a high tumor mutational burden (TMB) were detected. Conclusions: NGS from cerebrospinal fluid is feasible in routine clinical practice and yields therapeutically relevant alterations in a large subset of patients. Integration of this approach into a precision cancer medicine program might help to improve therapeutic options for patients with CNS cancer.

Xanthatin induces glioma cell apoptosis and inhibits tumor growth via activating endoplasmic reticulum stress-dependent CHOP pathway.

Xanthatin is a natural sesquiterpene lactone purified from Xanthium strumarium L., which has shown prominent antitumor activity against a variety of cancer cells. In the current study, we investigated the effect of xanthatin on the growth of glioma cells in vitro and in vivo, and elucidated the underlying mechanisms. In both rat glioma C6 and human glioma U251 cell lines, xanthatin (1-15 µM) dose-dependently inhibited cell viability without apparent effect on the cell cycle. Furthermore, xanthatin treatment dose-dependently induced glioma cell apoptosis. In nude mice bearing C6 glioma tumor xenografts, administration of xanthatin (10, 20, 40 mg·kg-1·d-1, ip, for 2 weeks) dose-dependently inhibited the tumor growth, but did not affect the body weight. More importantly, xanthatin treatment markedly increased the expression levels of the endoplasmic reticulum (ER) stress-related markers in both the glioma cell lines as well as in C6 xenografts, including glucose-regulated protein 78, C/EBP-homologous protein (CHOP), activating factor 4, activating transcription factor 6, spliced X-box binding protein-1, phosphorylated protein kinase R-like endoplasmic reticulum kinase, and phosphorylated eukaryotic initiation factor 2a. Pretreatment of C6 glioma cells with the ER stress inhibitor 4-phenylbutyric acid (4-PBA, 7 mM) or knockdown of CHOP using small interfering RNA significantly attenuated xanthatin-induced cell apoptosis and increase of proapoptotic caspase-3. These results demonstrate that xanthatin induces glioma cell apoptosis and inhibits tumor growth via activating the ER stress-related unfolded protein response pathway involving CHOP induction. Xanthatin may serve as a promising agent in the treatment of human glioma.

Management of CNS metastases in patients with EGFR mutation-positive NSCLC.

Central nervous system (CNS) metastases are a frequent and severe complication associated with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). The first- and second-generation EGFR tyrosine kinase inhibitors (TKIs) have shown considerable efficacy in EGFR-mutated NSCLC. However, their limited potential to cross the blood-brain barrier (BBB) renders them less effective in the management of CNS metastases in NSCLC. Osimertinib, a third-generation irreversible EGFR-TKI with good potential to cross the BBB, has shown significant clinical activity and acceptable safety profile in patients with EGFR-positive NSCLC brain and leptomeningeal metastases. The progression-free survival (PFS) of up to 15.2 months in CNS metastases patients in the FLAURA trial and the CNS objective response rates (ORRs) of 54% and 43% in the AURA/AURA2 and BLOOM trials, respectively, have established the role of osimertinib in patients with NSCLC with CNS metastases. The AURA3 trial also reported a PFS of 8.5 months and overall ORR of 71%. These data have supported osimertinib to be recognized as a "preferred" first-line treatment for EGFR-positive metastatic NSCLC by the National Comprehensive Cancer Network (NCCN). With limited treatment options available, upfront administration of osimertinib in patients with NSCLC irrespective of EGFR T790M and CNS metastases may improve the overall response rate and potentially reduce the adverse effects of radiotherapy. Our review focuses on the management of EGFR-mutated NSCLC CNS metastases in the context of recent NCCN guidelines.

Phase 1b trial of an ibrutinib-based combination therapy in recurrent/refractory CNS lymphoma.

Ibrutinib is a first-in-class inhibitor of Bruton tyrosine kinase (BTK) and has shown single-agent activity in recurrent/refractory central nervous system (CNS) lymphoma. Clinical responses are often transient or incomplete, suggesting a need for a combination therapy approach. We conducted a phase 1b clinical trial to explore the sequential combination of ibrutinib (560 or 840 mg daily dosing) with high-dose methotrexate (HD-MTX) and rituximab in patients with CNS lymphoma (CNSL). HD-MTX was given at 3.5 g/m2 every 2 weeks for a total of 8 doses (4 cycles; 1 cycle = 28 days). Ibrutinib was held on days of HD-MTX infusion and resumed 5 days after HD-MTX infusion or after HD-MTX clearance. Single-agent daily ibrutinib was administered continuously after completion of induction therapy until disease progression, intolerable toxicity, or death. We also explored next-generation sequencing of circulating tumor DNA (ctDNA) in cerebrospinal fluid (CSF) before and during treatment. The combination of ibrutinib, HD-MTX, and rituximab was tolerated with an acceptable safety profile (no grade 5 events, 3 grade 4 events). No dose-limiting toxicity was observed. Eleven of 15 patients proceeded to maintenance ibrutinib after completing 4 cycles of the ibrutinib/HD-MTX/rituximab combination. Clinical responses occurred in 12 of 15 patients (80%). Sustained tumor responses were associated with clearance of ctDNA from the CSF. This trial was registered at www.clinicaltrials.gov as #NCT02315326.

Novel agents for primary central nervous system lymphoma: evidence and perspectives.

Primary central nervous system lymphoma (PCNSL) is a rare aggressive extranodal non- Hodgkin lymphoma. Although high remission rates can be achieved with high-dose methotrexate-based immunochemotherapy, risk of relapse and associated death is still substantial in at least a third of patients. Novel agents for treating lymphoid malignancies have substantially enriched treatment options for PCNSL. We herein systematically review the existing clinical evidence of novel agents in treatment of PCNSL, summarize ongoing studies, and discuss perspectives. The body of evidence for novel agents is still limited to noncomparative studies, but the most promising approaches include Bruton kinase inhibition with ibrutinib and immunomodulatory treatment (eg, with lenalidomide). Targeting the mammalian target of rapamycin pathway does not seem to have a meaningful clinical benefit, and evidence of checkpoint inhibition with nivolumab is limited to anecdotal evidence. Future studies should embrace the concept of induction and maintenance therapy as well as the combination of drugs with different mechanisms of action. Selection of patients based on molecular profiling and relapse patterns should be another aspect informing future comparative trials, which are urgently needed to improve prognosis for patients with PCNSL.

The cluster [Re6Se8I6]3- penetrates biological membranes: drug-like properties for CNS tumor treatment and diagnosis.

Tumorigenic cell lines are more susceptible to [Re6Se8I6]3- cluster-induced death than normal cells, becoming a novel candidate for cancer treatment. Still, the feasibility of using this type of molecules in human patients remains unclear and further pharmacokinetics analysis is needed. Using coupled plasma optical emission spectroscopy, we determined the Re-cluster tissue content in injected mice, as a biodistribution measurement. Our results show that the Re-cluster successfully reaches different tissues, accumulating mainly in heart and liver. In order to dissect the mechanism underlying cluster biodistribution, we used three different experimental approaches. First, we evaluate the degree of lipophilicity by determining the octanol/water partition coefficient. The cluster mostly remained in the octanol fraction, with a coefficient of 1.86 ± 0.02, which indicates it could potentially cross cell membranes. Then, we measured the biological membrane penetration through a parallel artificial membrane permeability assays (PAMPA) assay. The Re-cluster crosses the artificial membrane, with a coefficient of 122 nm/s that is considered highly permeable. To evaluate a potential application of the Re-cluster in central nervous system (CNS) tumors, we analyzed the cluster's brain penetration by exposing cultured blood-brain-barrier (BBB) cells to increasing concentrations of the cluster. The Re-cluster effectively penetrates the BBB, reaching nearly 30% of the brain side after 24 h. Thus, our results indicate that the Re-cluster penetrates biological membranes reaching different target organs-most probably due to its lipophilic properties-becoming a promising anti-cancer drug with high potential for CNS cancer's diagnosis and treatment.

Effects of the Green Tea Polyphenol Epigallocatechin-3-Gallate on Glioma: A Critical Evaluation of the Literature.

The review discusses the effects of Epigallocatechin-3-gallate Gallate (EGCG) on glioma as a basis for future research on clinical application of EGCG. Epidemiological studies on the effects of green tea or EGCG on the risk of glioma is inconclusive due to the limited number of studies, the inclusion of all tea types in these studies, and the focus on caffeine rather than EGCG. In vivo experiments using EGCG monotherapy are inconclusive. Nevertheless, EGCG induces cell death, prevents cellular proliferation, and limits invasion in multiple glioma cell lines. Furthermore, EGCG enhances the efficacy of anti-glioma therapies, including irradiation, temozolomide, carmustine, cisplatin, tamoxifen, and TNF-related apoptosis-inducing ligand, but reduces the effect of bortezomib. Pro-drugs, co-treatment, and encapsulation are being investigated to enhance clinical applicability of EGCG. Mechanisms of actions of EGCG have been partly elucidated. EGCG has both anti-oxidant and oxidant properties. EGCG inhibits pro-survival proteins, such as telomerase, survivin, GRP78, PEA15, and P-gp. EGCG inhibits signaling of PDGFR, IGF-1R, and 67LR. EGCG reduces invasiveness of cancer cells by inhibiting the activities of various metalloproteinases, cytokines, and chemokines. Last, EGCG inhibits some NADPH-producing enzymes, thus disturbing redox status and metabolism of glioma cells. In conclusion, EGCG may be a suitable adjuvant to potentiate anti-glioma therapies.

Clinical significance of polyglutamylation in primary central nervous system lymphoma.

The therapeutic response to high-dose methotrexate (HD-MTX) therapy for primary central nervous system lymphoma (PCNSL) varies. Polyglutamylation is a reversible protein modification with a high occurrence rate in tumor cells. MTX incorporated into cells is polyglutamylated and strongly binds to dihydrofolate reductase without competitive inhibition by leucovorin (LV). Tumor cells with high polyglutamylation levels are selectively killed, whereas normal cells with lower polyglutamylation are rescued by LV. We hypothesized that the extent of polyglutamylation in tumor cells determines treatment resistance. Here, we investigated the therapeutic response of PCNSL to HD-MTX therapy with LV rescue based on polyglutamylation status. Among 113 consecutive PCNSL patients who underwent HD-MTX therapy in our department between 2001 and 2014, polyglutamylation was evaluated by immunostaining in 82 cases, with relationships between polyglutamylation and therapeutic response retrospectively examined. Human malignant lymphoma lines were used for in vitro experiments, and folpolyglutamate synthetase (FPGS), which induces polyglutamylation, was knocked down with short-hairpin RNA, and a stable cell line with a low rate of polyglutamylation was established. Cell viability after MTX treatment with LV rescue was evaluated using sodium butyrate (NaBu), a histone-deacetylase inhibitor that induces polyglutamylation by elevating FPGS expression. The complete response rate was significantly higher in the group with polyglutamylation than in the non-polyglutamylation group [58.1% (25/43) and 33.3% (13/39), respectively] (p < 0.05), and progression-free survival was also significantly increased in the group with polyglutamylation (p < 0.01). In vitro, the relief effect of LV after MTX administration was significantly enhanced after FPGS knockdown in al cell lines, whereas enhancement of FPGS expression by NaBu treatment significantly reduced this relief effect. These findings suggested that polyglutamylation could be a predictor of therapeutic response to HD-MTX therapy with LV rescue in PCNSL. Combination therapy with HD-MTX and polyglutamylation-inducing agents might represent a promising strategy for PCNSL treatment.

The Utility of Expert Diagnosis in Surgical Neuropathology: Analysis of Consultations Reviewed at 5 National Comprehensive Cancer Network Institutions.

The aim of this study was to characterize the type and degree of discrepancies between non-expert and expert diagnoses of CNS tumors to identify the value of consultations in surgical neuropathology. Neuropathology experts from 5 National Comprehensive Cancer Network (NCCN) member institutions participated in the review of 1281 consultations selected based on inclusion criteria. The consultation cases were re-reviewed at the NCCN headquarters to determine concordance with the original diagnoses. Among all consultations, 249 (19.4%) were submitted for expert diagnoses without final diagnoses from the submitting institution. Within the remaining 1032 patients, the serious/major discrepancy rate was 4.8%, and less serious and minor discrepancies were seen in 19.4% of the cases. The discrepancy rate was higher among patients who were referred to NCCN institutions for consultation compared to those who were referred for treatment only. The discrepancy rates, patient demographics, type of consultations and submitting institutions varied among participating NCCN institutions. Expert consultations identified a subset of cases with significant diagnostic discrepancies, and constituted the initial diagnoses in some cases. These data indicate that expert consultations in glial tumors and all types of pediatric CNS tumors can improve accurate diagnosis and enable appropriate management.

The inhibiting activity of meadowsweet extract on neurocarcinogenesis induced transplacentally in rats by ethylnitrosourea.

Inhibitory activity of a decoction of meadowsweet, given postnatally, was studied in rats at risk for neurogenic and renal tumors initiated by transplacental exposure to ethylnitrosourea (ENU). Chemical analysis of ethanol and aqueous extracts of meadowsweet has shown high content of biologically active flavonoids and tannins. Pregnant rats of LIO strain were given a single i.v. injection of ENU, 75 mg/kg, оn the 21st day of gestation. After weaning at 3 weeks after birth, the offspring were divided into two groups: the first was a positive control (ENU), while rats in the second group (ENU + meadowsweet) were given daily a decoction of meadowsweet as drinking water throughout their lifetime. All rats of the first group (ENU) developed multiple malignant tumors, which occurred in brain (86%), spinal cord (43%), peripheral and cranial nerves (29%) and in kidney (31%). More than one-third of CNS tumors were oligodendrogliomas. Mixed gliomas (oligoastrocytomas) occurred less frequently. All other types including astrocytomas, glioblastomas, and ependymomas were rare. All PNS tumors were neurinomas (schwannomas). The spectrum of tumors was similar in rats of the second group. Postnatal consumption of meadowsweet significantly reduced number of tumor-bearing rats (by 1.2 times), the incidence and multiplicity of CNS tumors (brain-by 2.0 and 2.1 times, respectively; spinal cord-by 3.1 and 3.0 times, respectively) and significantly increased latency period, compared to rats of the first group. No significant reduction in PNS or renal tumors was seen in rats given meadowsweet. Meadowsweet extract can be considered an effective cancer preventive agent especially as a neurocarcinogenesis inhibitor.