Central neurotoxicity of standard treatment in patients with newly-diagnosed high-grade glioma: a prospective longitudinal study

Long-term neurocognitive function and quality of life after multimodal therapy in adult glioma patients: a prospective long-term follow-up

PURPOSE

Multimodal therapies have significantly improved prognosis in glioma. However, in particular radiotherapy may induce long-term neurotoxicity compromising patients' neurocognition and quality of life. The present prospective multicenter study aimed to evaluate associations of multimodal treatment with neurocognition with a particular focus on hippocampal irradiation.

METHODS

Seventy-one glioma patients (WHO grade 1-4) were serially evaluated with neurocognitive testing and quality of life questionnaires. Prior to (baseline) and following further treatment (median 7.1 years [range 4.6-11.0] after baseline) a standardized computerized neurocognitive test battery (NeuroCog FX) was applied to gauge psychomotor speed and inhibition, verbal short-term memory, working memory, verbal and non-verbal memory as well as verbal fluency. Mean ipsilateral hippocampal radiation dose was determined in a subgroup of 27 patients who received radiotherapy according to radiotherapy plans to evaluate its association with neurocognition.

RESULTS

Between baseline and follow-up mean performance in none of the cognitive domains significantly declined in any treatment modality (radiotherapy, chemotherapy, combined radio-chemotherapy, watchful-waiting), except for selective attention in patients receiving chemotherapy alone. Apart from one subtest (inhibition), mean ipsilateral hippocampal radiation dose > 50 Gy (Dmean) as compared to < 10 Gy showed no associations with long-term cognitive functioning. However, patients with Dmean < 10 Gy showed stable or improved performance in all cognitive domains, while patients with > 50 Gy numerically deteriorated in 4/8 domains.

CONCLUSIONS

Multimodal glioma therapy seems to affect neurocognition less than generally assumed. Even patients with unilateral hippocampal irradiation with > 50 Gy showed no profound cognitive decline in this series.

Combination therapy with interferon-gamma as a potential therapeutic medicine in rat's glioblastoma: A multi-mechanism evaluation

BACKGROUND

This study assessed the effects of single or combined administration of temozolomide (TMZ) and interferon-gamma (IFN-ᵞ) on anxiety-like behaviors, balance disorders, learning and memory, TNF-α, IL-10, some oxidant and antioxidants factors with investigating the toll-like receptor-4 (TLR4) and p-CREB signaling pathway in C6-induced glioblastoma of rats.

METHODS

40 male Sprague-Dawley rats bearing intra-caudate nucleus (CN) culture medium or C6 inoculation were randomly divided into five groups as follows: Sham, Tumor, TMZ, IFN-ᵞ and a TMZ + IFN-ᵞ combination. The open-field test (OFT), elevated plus maze (EPM), rotarod, and passive avoidance test (PAT) were done on days 14-17. On day 17 after tumor implantation, brain tissues were extracted for histopathological evaluation. TNF-α, IL-10, SOD, GPX, TAC, MDA, the protein level of TLR4 and p-CREB was measured.

RESULTS

Combination therapy inhibited the growth of the tumor. Treatment groups alleviated tumor-induced anxiety-like behaviors and improved imbalance and memory impairment. SOD, GPX, and TAC decreased in the tumor group. The combination group augmented GPX and TAC. MDA decreased in treatment groups. TMZ, IFN-ᵞ reduced tumor-increased TNF-α and IL-10 level. The combination group declined TNF-α level in serum and IL-10 level in serum and brain. Glioblastoma induced significant upregulation of TLR4 and p-CREB in the brain which inhibited by IFN-ᵞ and TMZ+ IFN-ᵞ.

CONCLUSION

The beneficial effects of TMZ, IFN-ᵞ, and TMZ+ IFN-ᵞ on neurocognitive functioning of rats with C6-induced glioblastoma may be mediated via modulating oxidative stress, reduced cytokines, and the downregulation of expression of TLR4 and p-CREB. Combination treatment appears to be more effective than single treatment.

Mid-term treatment-related cognitive sequelae in glioma patients

Purpose

Cognitive functioning represents an essential determinant of quality of life. Since significant advances in neuro-oncological treatment have led to prolonged survival it is important to reliably identify possible treatment-related neurocognitive dysfunction in brain tumor patients. Therefore, the present study specifically evaluates the effects of standard treatment modalities on neurocognitive functions in glioma patients within two years after surgery.

Methods

Eighty-six patients with World Health Organization (WHO) grade 1–4 gliomas were treated between 2004 and 2012 and prospectively followed within the German Glioma Network. They received serial neuropsychological assessment of attention, memory and executive functions using the computer-based test battery NeuroCog FX. As the primary outcome the extent of change in cognitive performance over time was compared between patients who received radiotherapy, chemotherapy or combined radio-chemotherapy and patients without any adjuvant therapy. Additionally, the effect of irradiation and chemotherapy was assessed in subgroup analyses. Furthermore, the potential impact of the extent of tumor resection and histopathological characteristics on cognitive functioning were referred to as secondary outcomes.

Results

After a median of 16.8 (range 5.9–31.1) months between post-surgery baseline neuropsychological assessment and follow-up assessment, all treatment groups showed numerical and often even statistically significant improvement in all cognitive domains. The extent of change in cognitive functioning showed no difference between treatment groups. Concerning figural memory only, irradiated patients showed less improvement than non-irradiated patients (p = 0.029, η² = 0.06). Resected patients, yet not patients with biopsy, showed improvement in all cognitive domains. Compared to patients with astrocytomas, patients with oligodendrogliomas revealed a greater potential to improve in attentional and executive functions. However, the heterogeneity of the patient group and the potentially selected cohort may confound results.

Conclusion

Within a two-year post-surgery interval, radiotherapy, chemotherapy or their combination as standard treatment did not have a detrimental effect on cognitive functions in WHO grade 1–4 glioma patients. Cognitive performance in patients with adjuvant treatment was comparable to that of patients without.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11060-022-04044-1.

Recovery from the damage of cranial radiation modulated by memantine, an NMDA receptor antagonist, combined with hyperbaric oxygen therapy

BACKGROUND

Radiotherapy is an important treatment option for central nervous system malignancies. However, cranial radiation induces hippocampal dysfunction and white matter injury; this leads to cognitive dysfunction, and results in a reduced quality of life in patients. Excitatory glutamate signaling through N-methyl-d-aspartate receptors (NMDARs) plays a central role both in hippocampal neurogenesis and in the myelination of oligodendrocytes in the cerebrum.

METHODS

We provide a method for quantifying neurogenesis in human subjects in live brain during cancer therapy. Neuroimaging using originally created behavioral tasks was employed to examine human hippocampal memory pathway in patients with brain disorders.

RESULTS

Treatment with memantine, a non-competitive NMDAR antagonist, reversed impairment in hippocampal pattern separation networks as detected by functional magnetic resonance imaging. Hyperbaric preconditioning of the patients just before radiotherapy with memantine mostly reversed white matter injury as detected by whole brain analysis with Tract-Based Spatial Statics. Neuromodulation combined with the administration of hyperbaric oxygen therapy and memantine during radiotherapy facilitated the restoration of hippocampal function and white matter integrity, and improved higher cognitive function in patients receiving cranial radiation.

CONCLUSIONS

The method described herein, for diagnosis of hippocampal dysfunction, and therapeutic intervention can be utilized to restore some of the cognitive decline experienced by patients who have received cranial radiation. The underlying mechanism of restoration is the production of new neurons, which enhances functionality in pattern separation networks in the hippocampi, resulting in an increase in cognitive score, and restoration of microstructural integrity of white matter tracts revealed by Tract-Based Spatial Statics Analysis.

Pretreatment patient-reported cognitive function in patients with diffuse glioma

Purpose

Cognitive function is frequently assessed with objective neuropsychological tests, but patient-reported cognitive function is less explored. We aimed to investigate the preoperative prevalence of patient-reported cognitive impairment in patients with diffuse glioma compared to a matched reference group and explore associated factors.

Methods

We included 237 patients with diffuse glioma and 474 age- and gender-matched controls from the general population. Patient-reported cognitive function was measured using the cognitive function subscale in the European Organisation for Research and Treatment of Cancer QLQ-C30 questionnaire. The transformed scale score (0–100) was dichotomized, with a score of ≤ 75 indicating clinically important patient-reported cognitive impairment. Factors associated with preoperative patient-reported cognitive impairment were explored in a multivariable regression analysis.

Results

Cognitive impairment was reported by 49.8% of the diffuse glioma patients and by 23.4% in the age- and gender-matched reference group (p < 0.001). Patients with diffuse glioma had 3.2 times higher odds (95% CI 2.29, 4.58, p < 0.001) for patient-reported cognitive impairment compared to the matched reference group. In the multivariable analysis, large tumor volume, left tumor lateralization, and low Karnofsky Performance Status score were found to be independent predictors for preoperative patient-reported cognitive impairment.

Conclusions

Our findings demonstrate that patient-reported cognitive impairment is a common symptom in patients with diffuse glioma pretreatment, especially in patients with large tumor volumes, left tumor lateralization, and low functional levels. Patient-reported cognitive function may provide important information about patients’ subjective cognitive health and disease status and may serve as a complement to or as a screening variable for subsequent objective testing.

Sociocognitive Functioning and Psychosocial Burden in Patients with Brain Tumors

Simple Summary

After years of gauging the efficacy of tumor-directed therapies primarily by means of survival, a broader perspective on therapeutic outcome also focusses on patients’ everyday functional abilities. Besides neurocognition, a matter of high clinical relevance, “social cognition” may also affect well-being and quality of life (QoL) in brain tumor patients. Abilities that enable individuals to establish and maintain social relationships are summarized under the umbrella term “sociocognitive functioning”. These abilities encompass the understanding and sharing of emotional and mental states of other individuals as well as skills to detect and resolve interpersonal problems. These sociocognitive abilities may be challenged in highly demanding life situations such as brain tumor diagnosis and treatment. Therefore, we summarize the literature on psychosocial burden and sociocognitive functioning in adult brain tumor patients.

Abstract

Brain tumors may represent devastating diseases and neuro-oncological research in the past solely focused on development of better treatments to achieve disease control. The efficacy of tumor-directed treatment was evaluated by progression-free and overall survival. However, as neuro-oncological treatment became more effective, preservation and improvement of quality of life (QoL) was noticed to represent an important additional outcome measure. The need to balance between aggressive tumor-directed treatment and preservation of QoL was increasingly acknowledged in brain tumor patients. QoL is comprised by many determinants; one of those may have been rather neglected so far: social cognition. Since diagnosis and treatment of brain tumors represent demanding life situations, patients may experience increased psychosocial burden and the negative consequences of illness on well-being may be buffered by intact social relationships. These skills to build and maintain supportive social relationships essentially depend on the ability to empathize with others and to recognize and appropriately address social conflicts, i.e., “sociocognitive functioning”. Therefore, sociocognitive functions may influence QoL and treatment outcome. In this article, we review the literature on psychosocial burden and sociocognitive functioning in adult brain tumor patients.

Cumulative incidence and risk factors for radiation induced leukoencephalopathy in high grade glioma long term survivors

The incidence and risk factors associated with radiation-induced leukoencephalopathy (RIL) in long-term survivors of high-grade glioma (HGG) are still poorly investigated. We performed a retrospective research in our institutional database for patients with supratentorial HGG treated with focal radiotherapy, having a progression-free overall survival > 30 months and available germline DNA. We reviewed MRI scans for signs of leukoencephalopathy on T2/FLAIR sequences, and medical records for information on cerebrovascular risk factors and neurological symptoms. We investigated a panel of candidate single nucleotide polymorphisms (SNPs) to assess genetic risk. Eighty-one HGG patients (18 grade IV and 63 grade III, 50M/31F) were included in the study. The median age at the time of radiotherapy was 48 years old (range 18-69). The median follow-up after the completion of radiotherapy was 79 months. A total of 44 patients (44/81, 54.3%) developed RIL during follow-up. Twenty-nine of the 44 patients developed consistent symptoms such as subcortical dementia (n = 28), gait disturbances (n = 12), and urinary incontinence (n = 9). The cumulative incidence of RIL was 21% at 12 months, 42% at 36 months, and 48% at 60 months. Age > 60 years, smoking, and the germline SNP rs2120825 (PPARg locus) were associated with an increased risk of RIL. Our study identified potential risk factors for the development of RIL (age, smoking, and the germline SNP rs2120825) and established the rationale for testing PPARg agonists in the prevention and management of late-delayed radiation-induced neurotoxicity.

Older age is a protective factor for academic achievements irrespective of treatment modalities for posterior fossa brain tumours in children

The treatment of children with posterior fossa brain tumours (PFBT) impacts their long term functional and imaging outcomes. This study aimed to evaluate academic achievement correlated with long-term sequelae after different PFBT treatment modalities. The study cohort consisted of 110 survivors (median age at diagnosis 10.1 years and median time of follow up 13.2 years) who completed hearing questionnaires, neurological assessment and MRI of the brain ≥5 years after the end of treatment. There were three treatment groups. A cisplatin group which underwent cisplatin chemotherapy, radiotherapy and surgery (medulloblastoma N = 40), a radiotherapy group which underwent radiotherapy and surgery (astrocytoma/ependymoma N = 30), and a surgery group (astrocytoma N = 40). Academic achievement was correlated to the age at diagnosis, ototoxicity, Karnofsky score (KS), and MRI findings (Fazekas Score (FS)- treatment related parenchymal changes). For a modelled age at diagnosis of five years, the cisplatin group had lower academic achievements compared to the radiotherapy (p = 0.028) and surgery (p = 0.014) groups. Academic achievements evaluated at a modelled age of 10 years at diagnosis did not significantly differ among the treatment groups. The cisplatin group exhibited a higher occurrence of ototoxicity than the radiotherapy (p<0.019) and surgery groups (p<0.001); however, there was no correlation between ototoxicity and academic achievements (p = 0.722) in older age at diagnosis. The radiotherapy group exhibited lower KS than the surgery group (p<0.001). KS significantly influenced academic achievements in all groups (p<0.000). The cisplatin group exhibited higher FS than the surgery group (p<0.001) while FS did not correlate with academic achievement (p = 0.399). Older age is a protective factor for academic achievements irrespective of a treatment modality.

Longitudinal study of cognitive function in glioma patients treated with modern radiotherapy techniques and standard chemotherapy

Introduction: Cognitive function is an important outcome measure in patients with brain tumor, providing information about the patient's clinical situation, treatment effects and possible progressive disease. The aim of this longitudinal study was to evaluate effects of the currently used radiation and chemotherapy treatment on cognitive function and to investigate associations between cognitive function at baseline and progression as well as overall survival.Methods: 32 patients newly diagnosed with malignant glioma were evaluated at baseline with CNS Vital Signs (CNS-VS), a computerized standardized neuropsychological test battery, prior to arc-based radiotherapy and concomitant chemotherapy with Temozolomide. CNS-VS measures the cognitive functions known to be affected in patients with brain tumor, covering nine cognitive domains. Follow-up cognitive evaluations were performed in 26 patients after 3.5 months and in 13 patients 1 year after treatment start.Results: Overall cognitive scores were lower in the studied patient cohort at baseline compared to standardized domain scores. At 3.5 months follow-up cognitive functioning was slightly decreased, but only in 1/9 cognitive domains - visual memory - where significant changes were found compared to baseline test results. Similarly, at 12 months follow-up no significant changes in cognitive test results were seen compared to baseline examination, except for a decrease in the visual memory domain. In relation to early progression, the most significant cognitive deficits were dysfunctional visual memory and low executive functioning at baseline. Low executive function at baseline correlated most significantly with shorter overall survival.Conclusion: The present study suggests that the currently used arc-based radiotherapy and chemotherapy might affect cognitive function less negatively than previously described during treatment and in the first year after treatment in malignant glioma patients. In general, a high cognitive test score at baseline was associated with longer time to progression and with longer survival.

AVNP2 protects against cognitive impairments induced by C6 glioma by suppressing tumour associated inflammation in rats

Glioblastoma is a kind of malignant tumour and originates from the central nervous system. In the last century, some researchers and clinician have noticed that the psychosocial and neurocognitive functioning of patients with malignant gliomas can be impaired. Many clinical studies have demonstrated that part of patients, adults or children, diagnosed with glioblastoma will suffer from cognitive deficiency during their clinical course, especially in long-term survivors. Many nanoparticles (NPs) can inhibit the biological functions of tumours by modulating tumour-associated inflammation, which provokes angiogenesis and tumour growth. As one of the best antiviral nanoparticles (AVNPs), AVNP2 is the 2nd generation of AVNP2 that have been conjugated to graphite-graphene for improving physiochemical performance and reducing toxicity. AVNP2 inactivates viruses, such as the H1N1 and H5N1influenza viruses and even the SARS coronavirus, while it inhibits bacteria, such as MRSA and E. coli. As antimicrobials, nanoparticles are considered to be one of the vectors for the administration of therapeutic compounds. Yet, little is known about their potential functionalities and toxicities to the neurotoxic effects of cancer. Herein, we explored the functionality of AVNP2 on inhibiting C6 in glioma-bearing rats. The novel object-recognition test and open-field test showed that AVNP2 significantly improved the neuro-behaviour affected by C6 glioma. AVNP2 also alleviated the decline of long-term potentiation (LTP) and the decreased density of dendritic spines in the CA1 region induced by C6. Western blot assay and immunofluorescence staining showed that the expressions of synaptic-related proteins (PSD-95 and SYP) were increased, and these findings were in accordance with the results mentioned above. It revealed that the sizes of tumours in C6 glioma-bearing rats were smaller after treatment with AVNP2. The decreased expression of inflammatory factors (IL-1β, IL-6 and TNF-α) by Western blotting assay and ELISA, angiogenesis protein (VEGF) by Western blotting assay and other related proteins (BDNF, NF-ĸB, iNOS and COX-2) by Western blotting assay in peri-tumour tissue indicated that AVNP2 could control tumour-associated inflammation, thus efficiently ameliorating the local inflammatory condition and, to some extent, inhibiting angiogenesis in C6-bearing rats. In conclusion, our results suggested that AVNP2 could have an effect on the peri-tumor environment, obviously restraining the growth progress of gliomas, and eventually improving cognitive levels in C6-bearing rats.

Sensitivity of the Montreal Cognitive Assessment in screening for cognitive impairment in patients with newly diagnosed high-grade glioma

INTRODUCTION

Cognitive impairment is frequent in patients with high-grade glioma and requires cognitive follow-up. Cognitive screening tools such as the Montreal Cognitive Assessment (MoCA) have been used to assess cognition in these patients. Here we assessed the sensitivity of the MoCA in screening for cognitive impairment in a cohort of 156 patients with newly-diagnosed high-grade glioma, after surgery and before radiochemotherapy.

METHODS

We assessed cognitive performance with the MoCA and a neuropsychological battery. Cognitive scores were analyzed in terms of a previously validated framework designed to control false positives and data for 1003 control participants from the GRECOGVASC study. After comparison of performance on the tests, we used stepwise logistic regression to produce a cognitive summary score from the neuropsychological battery. Then we analyzed sensitivity and specificity of the MoCA with receiver operator characteristic (ROC) curve analysis.

RESULTS

Both raw and adjusted MoCA scores showed only moderate sensitivity. The area under the ROC curve was 0.759 (95% CI 0.703-0.815) for the raw score and 0.788 (95% CI 0.734-0.842) for the adjusted score. Optimal discrimination was obtained with a raw score ≤ 25 (sensitivity: 0.526; specificity: 0.832; positive predictive value: 0.2; negative predictive value: 0.96) and an adjusted score - 0.603 (sensitivity: 0.716; specificity: 0.768; positive predictive value: 0.24; negative predictive value: 0.96).

CONCLUSION

The moderate sensitivity of MoCA indicates that it is not a suitable screening tool for detecting cognitive impairment in patients with newly-diagnosed high-grade glioma.

A systematic review of cognitive function in patients with glioblastoma undergoing surgery

Background

Patients with glioblastoma (GB) are more likely to suffer cognitive deficits with poor quality of life as compared with lower-grade glioma patient groups, for whom cognition research is plentiful. The objective of this systematic review is to evaluate the cognitive function of patients with GB before and after surgery.

Methods

This review was prospectively registered with PROSPERO. PubMed and EMBASE searches were performed, most recently March 15, 2018. Inclusion criteria were adult patients, histologically confirmed GB, and cognitive tests conducted before and/or after surgery. Screening and data extraction were carried out independently by 2 authors.

Results

A total of 512 abstracts were screened. Nineteen studies were included with 902 participants, of whom only 423 had histologically confirmed GB. Only 11 studies tested cognitive function both before and after surgery. A total of 114 different cognitive tests were used. The most common test was used in only 9 studies; 82 tests were used only once. Follow-up time ranged from 1 week to 16 months with extremely high dropout rates. Eighteen of 19 studies reported cognitive deficits in their samples, with prevalence ranging from 22% to 100% (median 64%, interquartile range 42%). Only 1/11 longitudinal studies reported normal cognitive function, 3/11 reported initial deficits with improvement after surgery, 3/11 reported static deficits, and 4/11 reported deterioration.

Conclusion

There is a consistently high risk of cognitive deficit for patients with GB undergoing surgery. The included studies showed marked heterogeneity in study design, case-mix of included diagnoses, and the type and timing of cognitive tests used. We highlight considerations for the design of future studies to avoid such bias.

Impact of Cognitive Impairment in Patients with Gliomas

OBJECTIVES

To address the estimated rates of incidence, potential underlying etiologies, and cognitive domains affected from diagnosis and treatment. To describe potential cognitive function interventions.

DATA SOURCES

PubMed.

CONCLUSION

Adults with gliomas report that the most distressing, persistent, and greatest negative impact on their lives relates to the cognitive impairment they experience. However, there are several potential interventions that may prevent cognitive decline during treatment or maintain cognitive function long term.

IMPLICATIONS FOR NURSING PRACTICE

Awareness of cognitive sequela that adults with gliomas face can lead to early identification, full neurocognitive profiling, and implementation of evidence-based interventions for those experiencing cognitive impairments following cancer treatment.

Cognitive impairment and morphological changes after radiation therapy in brain tumors: A review

Life expectancy of patients treated for brain tumors has lengthened due to the therapeutic improvements. Cognitive impairment has been described following brain radiotherapy, but the mechanisms leading to this adverse event remain mostly unknown. Technical evolutions aim at enhancing the therapeutic ratio. Sparing of the healthy tissues has been improved using various approaches; however, few dose constraints have been established regarding brain structures associated with cognitive functions. The aims of this literature review are to report the main brain areas involved in cognitive adverse effects induced by radiotherapy as described in literature, to better understand brain radiosensitivity and to describe potential future improvements.

Group Changes in Cognitive Performance After Surgery Mask Changes in Individual Patients with Glioblastoma

BACKGROUND

There is a growing interest to include evaluations of cognitive performance in the clinical management of patients with glioblastoma (GBM). However, as changes in cognitive performance of a group may mask changes in individual patients, study results are often difficult to transfer into clinical practice. We focused on the comparison of group versus individual changes in neuropsychological performance of patients with GBM after initial surgical treatment.

METHODS

Patients underwent neuropsychological evaluation using CNS Vital Signs 1 day prior to and 3 months after surgery. Two-tailed paired-samples t tests were conducted to assess changes on the group level. Reliable change indices (RCIs) that correct for practice effects and imperfect test-retest reliabilities were used to examine changes in individual patients.

RESULTS

Cognitive dysfunction was common (>80%) both before and 3 months after surgery in this sample of 82 patients with GBM. Whereas group analyses revealed minimal changes in performance over time, RCIs demonstrated that most patients (89%) showed changes in performance in at least 1 cognitive domain. Half of these individual patients solely showed improvements, a quarter solely showed declines, and another quarter showed both improvements and declines.

CONCLUSIONS

This study clearly demonstrates that important individual changes in performance are masked when looking only at group results. Future studies should more often use an individual patient approach to enhance knowledge transfer into clinical practice.

Targeting metabotropic glutamate receptors in the treatment of primary brain tumors

In spite of the recent advancement in the molecular characterization of malignant gliomas and medulloblastomas, the treatment of primary brain tumors remains suboptimal. The use of small molecule inhibitors of intracellular signaling pathways, inhibitors of angiogenesis, and immunotherapic agents is limited by systemic adverse effects, limited brain penetration, and, in some cases, lack of efficacy. Thus, adjuvant chemo-therapy and radiotherapy still remain the gold standard in the treatment of grade-IV astrocytoma (glioblastoma multiforme) and medulloblastoma. We review evidence that supports the development of mGlu3 receptor antagonists as add-on drugs in the treatment of malignant gliomas. These drugs appear to display pleiotropic effect on tumor cells, affecting proliferation, differentiation, and response to chemotherapy. mGlu1 and mGlu4 receptors could also be targeted by potential anticancer agents in the treatment of malignant gliomas and medulloblastoma, but extensive research is required for target validation.

Seizure response to perampanel in drug-resistant epilepsy with gliomas: early observations

Drug-resistant epilepsy (DRE) occurs commonly in gliomas, possibly due to a shared mechanism of AMPA-activation involving both seizure activity and tumor growth. We tested the AMPA-receptor blocker perampanel (PER) in patients with DRE in low- and high-grade gliomas. Seizure response was defined as 50% drop in seizure frequency or as seizure-freedom. Cognitive function was examined by computerized test on cognitive speed (CTCS), which is sensitive to the type of cognitive dysfunction associated with epilepsy and use of anticonvulsants. Treatment policy included reduction of dose or discontinuation of one or more concurrent AEDs, once a seizure-free response was observed. Twelve patients were included patients, median age 41 years, 9 men versus 3 women and 6 months median duration of follow-up. An objective seizure response (75%) was observed in 9 (75%) out of 12 patients: 50%-seizure response in 3, seizure-freedom in 6, which is plainly more than seen with other types of DRE. Side-effects occurred in six patients. Cognitive function as examined by CTCS improved in six out of eight associated withlowering of concurrent AEDs. The final median dose of PER was 8 mg (varying between 2 and 12 mg). These results of an objective seizure response in 9 (75%) out of 12 patients treated by PER in DRE may be interpreted as a surrogate-marker of tumor response secondary to AMPA blockade, advancing confirmation by MR imaging. These results warrant further study of PER on tumor activity in gliomas.

Cognitive outcome after radiotherapy in brain tumor

PURPOSE OF REVIEW

Survival of brain tumor patients has increased with improvements in cancer treatments. However, treatments like radiotherapy can be neurotoxic and thus new end-points in clinical trials, as well as in individual management, have appeared. This article reviews the cognitive outcomes after radiotherapy in brain tumor patients, focusing on radiation-induced impairments, and then discusses actual cognitive assessment limitations.

RECENT FINDINGS

Although physiopathology of radiation-induced cognitive impairments remains elusive, a general course can be described as acute, early-delayed, and late-delayed effects corresponding to different processes. The last is of high interest because the related impairments are irreversible. In this context, a cognitive assessment should be performed as often as possible, but actual tools are unfortunately not developed. Nevertheless, with respect to neuro-oncologic specificities, new cognitive tools could be developed to overcome these limitations.

SUMMARY

Improvements in neuropsychologic assessment for brain tumor patients are urgently needed. A dynamic vision of radiation-induced cognitive impairments appears inevitable and should lead to a change in actual considerations about neurotoxicity follow-up.

Melatonergic system-based two-gene index is prognostic in human gliomas

Gliomas, the most common primary brain tumors in adults, are classified into four malignancy grades according to morphological features. Recent studies have shown that melatonin treatment induces cytotoxicity in glioma-initiating cells and reduces the invasion and migration of glioma cell lines, inhibiting the nuclear factor κB (NFκB) oncopathway. Given that C6 rat glioma cells produce melatonin, we investigated the correlation between the capacity of gliomas to synthesize/metabolize melatonin and their overall malignancy. We first characterized the melatonergic system of human gliomas cell lines with different grades of aggressiveness (HOG, T98G, and U87MG) and demonstrated that glioma-synthesized melatonin exerts an autocrine antiproliferative effect. Accordingly, the sensitivity to exogenous melatonin was higher for the most aggressive cell line, U87MG, which synthesized/accumulated less melatonin. Using The Cancer Genome Atlas RNAseq data of 351 glioma patients, we designed a predictive model of the content of melatonin in the tumor microenvironment, the ASMT:CYP1B1 index, combining the gene expression levels of melatonin synthesis and metabolism enzymes. The ASMT:CYP1B1 index negatively correlated with tumor grade, as well as with the expression of pro-proliferation and anti-apoptotic NFκB target genes. More importantly, the index was a grade- and histological type-independent prognostic factor. Even when considering only high-grade glioma patients, a low ASMT:CYP1B1 value, which suggests decreased melatonin and enhanced aggressiveness, was strongly associated with poor survival. Overall, our data reveal the prognostic value of the melatonergic system of gliomas and provide insights into the therapeutic role of melatonin.

Complications from radiotherapy

Radiotherapy (RT) of the brain is associated with significant stigma in the neuro-oncology community. This is primarily because of the potentially severe complications with which it may be associated. These complications, especially in subacute and latent settings, are often unpredictable, potentially progressive, and irreversible. The onset of complications may start from the first fraction of 2 Gy, continuing over several months after end of RT with persistent drowsiness and apathy. It may also extend over many years with progressive onset of neurocognitive impairments such as memory decline, and diminished focus/attention. For long-term survivors, such as young patients irradiated for a favorable low-grade glioma, quality of life can be seriously impacted by RT. It is essential, as in the pediatric field, to propose patient-specific regimens from the very outset of therapy. The use of molecular biomarkers to better predict survival, control of comorbidities along with judicious use of medications such as steroids and antiepileptics, improved targeting with the help of modern imaging and RT techniques, modulation of the dose, and fractionation aimed at limiting integral dose to the healthy brain all have the potential to minimize treatment-related complications while maintaining the therapeutic efficacy for which RT is known. Sparing "radiosensitive" areas such as hippocampi could have a modest but measurable impact with regard to cognitive preservation, an effect that can possibly be enhanced when used in conjunction with memantine and/or donepezil.

EpiBrainRad: an epidemiologic study of the neurotoxicity induced by radiotherapy in high grade glioma patients

Background

Radiotherapy is one of the most important treatments of primary and metastatic brain tumors. Unfortunately, it can involve moderate to severe complications among which leukoencephalopathy is very frequent and implies cognitive deficits such as memory, attention and executive dysfunctions. However, the incidence of this complication is not well established and the risk factors and process are poorly understood. The main objective of the study is to improve knowledge on radio-induced leukoencephalopathy based on pluridisciplinar approaches combining cognitive, biologic, imagery and dosimetric investigations.

Method/Design

The EpiBrainRad study is a prospective cohort study including newly diagnosed high grade gliomas patients treated by radiotherapy and concomitant-adjuvant temozolomide chemotherapy. Patients are included between their surgery and first day of radio-chemotherapy, and the follow-up lasts for 3 years after treatment. Cognitive functioning assessments, specific blood biomarkers measures and magnetic resonance imagery are performed at different moment during the follow-up, and a specific dosimetric assessment of organs involved in the beam fields is performed. Firstly, leukoencephalopathy incidence rate will be estimated in this population. Secondly, correlations between cognitive impairments and dosimetry, biomarkers ranges and anomalies on imagery will be analyzed in order to better understand the onset and evolution of cognitive decrement associated with radiotherapy. Furthermore, a new cognitive test, quickly and easily performed, will be studied to determine its sensibility to detect leukoencephalopathy decrement.

Discussion

With an original multidisciplinary approach, the EpiBrainRad study aims to improve knowledge on radio-induced leukoencephalopathy in order to improve its early diagnosis and prevention. The main challenge is to preserve quality-of-life after cancer treatments which imply to study the incidence of radiation-induced complications and their associated risk factors.

Trial Registration

NCT02544178

MiR-302c-3p suppresses invasion and proliferation of glioma cells via down-regulating metadherin (MTDH) expression

Glioma is the most common malignant brain tumors with poor prognosis. The molecular events involved in the development and progression of glioma remain unclear. In this study, the expression levels of miR-302c-3p were examined in glioma tissues by qRT-PCR. The in vitro and in vivo functional effects of miR-302c-3p were examined further. Luciferase reporter assays were conducted to confirm the targeting associations. Results showed that the expression level of miR-302c-3p in glioma tissues was significantly lower than those in normal brain tissues (P < 0.001). The decreased expression of mi-302c-3p in glioma was positively associated with WHO grade (P < 0.001). Up-regulation of MTDH was also detected in glioma tumors compared with normal brain tissues (P = 0.0027) and is inversely correlated with miR-302c-3p expression (P = 0.003, R(2) = 0.4065). MTDH mRNA is a direct target of miR-302c-3p, whose ectopic expression decreases MTDH expression through binding to its 3'-untranslated region. Overexpression of miR-302c-3p results in a dramatic inhibition of glioma cells proliferation and invasion in vitro and in vivo. These data suggest that miR-302c-3p play a pivotal role in the progression of glioma by targeting MTDH and is a potential inhibitor in glioma treatment.

Bradykinin antagonists and thiazolidinone derivatives as new potential anti-cancer compounds

Glioblastoma (GB), the most aggressive brain tumour, and mantle cell lymphoma (MCL), a rare but very aggressive type of lymphoma, are highly resistant to chemotherapy. GB and MCL chemotherapy gives very modest results, the vast majority of patients experience recurrent disease. To find out the new treatment modality for drug-resistant GB and MCL cells, combining of bradykinin (BK) antagonists with conventional temozolomide (TMZ) treatment, and screening of thiazolidinones derivatives were the main objectives of this work. As it was revealed here, BKM-570 was the lead compound among BK antagonists under investigation (IC50 was 3.3 μM) in human GB cells. It strongly suppressed extracellular signal-regulated kinases 1/2 (ERK1/2) and protein kinase B (AKT) phosphorylation. BK antagonists did not decrease the viability of MCL cells, thus showing the cell-specific mode, while thiazolidinone derivatives, a novel group of promising anti-tumour compounds inhibited proliferation of MCL cells: IC₅₀ of ID 4526 and ID 4527 compounds were 0.27 μM and 0.16 μM, correspondingly. However, single agents are often not effective in clinic due to activation of collateral pathways in tumour cells. We demonstrated a strong synergistic effect after combinatorial treatment by BKM-570 together with TMZ that drastically increased cytotoxic action of this drug in rat and human glioma cells. Small proportion of cells was still viable after such treatment that could be explained by presence of TMZ-resistant cells in the population. It is possible to expect that the combined therapy aimed simultaneously at different elements of tumourigenesis will be more effective with lower drug concentrations than the first-line drug temozolomide used alone in clinics.