Effect of anti-epileptic drugs on the survival of patients with glioblastoma multiforme: A retrospective, single-center study

Anti-epileptic drug use during adjuvant chemo-radiotherapy is associated with poorer survival in patients with glioblastoma: A nationwide population-based cohort study

INTRODUCTION

There are emerging but inconsistent evidences about anti-epileptic drugs (AEDs) as radio- or chemo-sensitizers to improve survival in glioblastoma patients. We conducted a nationwide population-based study to evaluate the impact of concurrent AED during post-operative chemo-radiotherapy on outcome.

MATERIAL AND METHODS

A total of 1057 glioblastoma patients were identified by National Health Insurance Research Database and Cancer Registry in 2008-2015. Eligible criteria included those receiving surgery, adjuvant radiotherapy and temozolomide, and without other cancer diagnoses. Survival between patients taking concurrent AED for 14 days or more during chemo-radiotherapy (AED group) and those who did not (non-AED group) were compared, and subgroup analyses for those with valproic acid (VPA), levetiracetam (LEV), or phenytoin were performed. Multivariate analyses were used to adjust for confounding factors.

RESULTS

There were 642 patients in the AED group, whereas 415 in the non-AED group. The demographic data was balanced except trend of more patients in the AED group had previous drug history of AEDs (22.6% vs. 18%, P 0.078). Overall, the AED group had significantly increased risk of mortality (HR = 1.18, P 0.016) compared to the non-AED group. Besides, an adverse dose-dependent relationship on survival was also demonstrated in the AED group (HR = 1.118, P 0.0003). In subgroup analyses, the significant detrimental effect was demonstrated in VPA group (HR = 1.29,P 0.0002), but not in LEV (HR = 1.18, P 0.079) and phenytoin (HR = 0.98, P 0.862).

CONCLUSIONS

Improved survival was not observed in patients with concurrent AEDs during chemo-radiotherapy. Our real-world data did not support prophylactic use of AEDs for glioblastoma patients.

Unexplained Causes of Glioma-Associated Epilepsies: A Review of Theories and an Area for Research

Approximately 30% of glioma patients are able to survive beyond one year postdiagnosis. And this short time is often overshadowed by glioma-associated epilepsy. This condition severely impairs the patient's quality of life and causes great suffering. The genetic, molecular and cellular mechanisms underlying tumour development and epileptogenesis remain incompletely understood, leading to numerous unanswered questions. The various types of gliomas, namely glioblastoma, astrocytoma and oligodendroglioma, demonstrate distinct seizure susceptibility and disease progression patterns. Patterns have been identified in the presence of IDH mutations and epilepsy, with tumour location in cortical regions, particularly the frontal lobe, showing a more frequent association with seizures. Altered expression of TP53, MGMT and VIM is frequently detected in tumour cells from individuals with epilepsy associated with glioma. However, understanding the pathogenesis of these modifications poses a challenge. Moreover, hypoxic effects induced by glioma and associated with the HIF-1a factor may have a significant impact on epileptogenesis, potentially resulting in epileptiform activity within neuronal networks. We additionally hypothesise about how the tumour may affect the functioning of neuronal ion channels and contribute to disruptions in the blood-brain barrier resulting in spontaneous depolarisations.

The complexities underlying epilepsy in people with glioblastoma

Seizures are among the most common clinical signs in people with glioblastoma. Advances over the past 5 years, including new clinical trial data, have increased the understanding of why some individuals with glioblastoma are susceptible to seizures, how seizures manifest clinically, and what implications seizures have for patient management. The pathophysiology of epilepsy in people with glioblastoma relates to a combination of intrinsic epileptogenicity of tumour tissue, alterations in the tumour and peritumoural microenvironment, and the physical and functional disturbance of adjacent brain structures. Successful management of epilepsy in people with glioblastoma remains challenging; factors such as drug-drug interactions between cancer therapies and antiseizure medications, and medication side-effects, can affect seizure outcomes and quality of life. Advances in novel therapies provide some promise for people with glioblastoma; however, the effects of these therapies on seizures are yet to be fully determined. Looking forward, insights into electrical activity as a driver of tumour cell growth and the intrinsic hyperexcitability of tumour tissue might represent useful targets for treatment and disease modification. There is a pressing need for large randomised clinical trials in this field.

Epilepsy and brain tumors: Two sides of the same coin

Epilepsy is the most common symptom in patients with brain tumors. The shared genetic, molecular, and cellular mechanisms between tumorigenesis and epileptogenesis represent 'two sides of the same coin'. These include augmented neuronal excitatory transmission, impaired inhibitory transmission, genetic mutations in the BRAF, IDH, and PIK3CA genes, inflammation, hemodynamic impairments, and astrocyte dysfunction, which are still largely unknown. Low-grade developmental brain tumors are those most commonly associated with epilepsy. Given this strict relationship, drugs able to target both seizures and tumors would be of extreme clinical usefulness. In this regard, anti-seizure medications (ASMs) are optimal candidates as they have well-characterized effects and safety profiles, do not increase the risk of developing cancer, and already offer well-defined seizure control. The most important ASMs showing preclinical and clinical efficacy are brivaracetam, lacosamide, perampanel, and especially valproic acid and levetiracetam. However, the data quality is low or limited to preclinical studies, and results are sometimes conflicting. Future trials with a prospective, randomized, and controlled design accounting for different prognostic factors will help clarify the role of these ASMs and the clinical setting in which they might be used. In conclusion, brain tumor-related epilepsies are clear examples of how close, multidisciplinary collaborations among investigators with different expertise are warranted for pursuing scientific knowledge and, more importantly, for the well-being of patients needing targeted and effective therapies.

Antitumor Potential of Antiepileptic Drugs in Human Glioblastoma: Pharmacological Targets and Clinical Benefits

Glioblastoma (GBM) is characterized by fast-growing cells, genetic and phenotypic heterogeneity, and radio-chemo-therapy resistance, contributing to its dismal prognosis. Various medical comorbidities are associated with the natural history of GBM. The most disabling and greatly affecting patients' quality of life are neurodegeneration, cognitive impairment, and GBM-related epilepsy (GRE). Hallmarks of GBM include molecular intrinsic mediators and pathways, but emerging evidence supports the key role of non-malignant cells within the tumor microenvironment in GBM aggressive behavior. In this context, hyper-excitability of neurons, mediated by glutamatergic and GABAergic imbalance, contributing to GBM growth strengthens the cancer-nervous system crosstalk. Pathogenic mechanisms, clinical features, and pharmacological management of GRE with antiepileptic drugs (AEDs) and their interactions are poorly explored, yet it is a potentially promising field of research in cancer neuroscience. The present review summarizes emerging cooperative mechanisms in oncogenesis and epileptogenesis, focusing on the neuron-to-glioma interface. The main effects and efficacy of selected AEDs used in the management of GRE are discussed in this paper, as well as their potential beneficial activity as antitumor treatment. Overall, although still many unclear processes overlapping in GBM growth and seizure onset need to be elucidated, this review focuses on the intriguing targeting of GBM-neuron mutual interactions to improve the outcome of the so challenging to treat GBM.

From HDAC to Voltage-Gated Ion Channels: What's Next? The Long Road of Antiepileptic Drugs Repositioning in Cancer

Simple Summary

Although in the last decades the clinical outcome of cancer patients considerably improved, the major drawbacks still associated with chemotherapy are the unwanted side effects and the development of drug resistance. Therefore, a continuous effort in trying to discover new tumor markers, possibly of diagnostic, prognostic and therapeutic value, is being made. This review is aimed at highlighting the anti-tumor activity that several antiepileptic drugs (AEDs) exert in breast, prostate and other types of cancers, mainly focusing on their ability to block the voltage-gated Na⁺ and Ca⁺⁺ channels, as well as to inhibit the activity of histone deacetylases (HDACs), all well-documented tumor markers and/or molecular targets. The existence of additional AEDs molecular targets is highly suspected. Therefore, the repurposing of already available drugs as adjuvants in cancer treatment would have several advantages, such as reductions in dose-related toxicity CVs will be sent in a separate mail to the indicated address of combined treatments, lower production costs, and faster approval for clinical use.

Abstract

Cancer is a major health burden worldwide. Although the plethora of molecular targets identified in the last decades and the deriving developed treatments, which significantly improved patients’ outcome, the occurrence of resistance to therapies remains the major cause of relapse and mortality. Thus, efforts in identifying new markers to be exploited as molecular targets in cancer therapy are needed. This review will first give a glance on the diagnostic and therapeutic significance of histone deacetylase (HDAC) and voltage gated ion channels (VGICs) in cancer. Nevertheless, HDAC and VGICs have also been reported as molecular targets through which antiepileptic drugs (AEDs) seem to exert their anticancer activity. This should be claimed as a great advantage. Indeed, due to the slowness of drug approval procedures, the attempt to turn to off-label use of already approved medicines would be highly preferable. Therefore, an updated and accurate overview of both preclinical and clinical data of commonly prescribed AEDs (mainly valproic acid, lamotrigine, carbamazepine, phenytoin and gabapentin) in breast, prostate, brain and other cancers will follow. Finally, a glance at the emerging attempt to administer AEDs by means of opportunely designed drug delivery systems (DDSs), so to limit toxicity and improve bioavailability, is also given.

The effect of levetiracetam treatment on survival in patients with glioblastoma: a systematic review and meta-analysis

BACKGROUND

Levetiracetam (LEV) is an anti-epileptic drug (AED) that sensitizes glioblastoma (GBM) to temozolomide (TMZ) chemotherapy by inhibiting O⁶-methylguanine-DNA methyltransferase (MGMT) expression. Adding LEV to the standard of care (SOC) for GBM may improve TMZ efficacy. This study aimed to pool the existing evidence in the literature to quantify LEV's effect on GBM survival and characterize its safety profile to determine whether incorporating LEV into the SOC is warranted.

METHOD

A search of CINAHL, Embase, PubMed, and Web of Science from inception to May 2021 was performed to identify relevant articles. Hazard ratios (HR), median overall survival, and adverse events were pooled using random-effect models. Meta-regression, funnel plots, and the Newcastle-Ottawa Scale were utilized to identify sources of heterogeneity, bias, and statistical influence.

RESULTS

From 20 included studies, 5804 GBM patients underwent meta-analysis, of which 1923 (33%) were treated with LEV. Administration of LEV did not significantly improve survival in the entire patient population (HR 0.89, p = 0.094). Significant heterogeneity was observed during pooling of HRs (I² = 75%, p < 0.01). Meta-regression determined that LEV treatment effect decreased with greater rates of MGMT methylation (RC = 0.03, p = 0.02) and increased with greater proportions of female patients (RC = - 0.05, p = 0.002). Concurrent LEV with the SOC for GBM did not increase odds of adverse events relative to other AEDs.

CONCLUSIONS

Levetiracetam treatment may not be effective for all GBM patients. Instead, LEV may be better suited for treating specific molecular profiles of GBM. Further studies are necessary to identify optimal GBM candidates for LEV.

Levetiracetam as a sensitizer of concurrent chemoradiotherapy in newly diagnosed glioblastoma: An open-label phase 2 study

BACKGROUND

An open-label single-arm phase 2 study was conducted to evaluate the role of levetiracetam as a sensitizer of concurrent chemoradiotherapy (CCRT) for patients with newly diagnosed glioblastoma. This study aimed to determine the survival benefit of levetiracetam in conjunction with the standard treatment for glioblastoma.

METHODS

Major eligibility requirements included histologically proven glioblastoma in the supratentorial region, patients 18 years or older, and Eastern Cooperative Oncology Group (ECOG) performance status of 0-2. Levetiracetam was given at 1,000-2,000 mg daily in two divided doses during CCRT and adjuvant chemotherapy thereafter. The primary and the secondary endpoints were 6-month progression-free survival (6mo-PFS) and 24-month overall survival (24mo-OS), respectively. Outcomes of the study group were compared to those of an external control group.

RESULTS

Between July 2016 and January 2019, 76 patients were enrolled, and 73 patients were included in the final analysis. The primary and secondary outcomes were improved in the study population compared to the external control (6mo-PFS, 84.9% vs. 72.3%, p = 0.038; 24mo-OS, 58.0% vs. 39.9%, p = 0.018), but the differences were less prominent in a propensity score-matched analysis (6mo-PFS, 88.0% vs. 76.9%, p = 0.071; 24mo-OS, 57.1% vs. 38.8%, p = 0.054). In exploratory subgroup analyses, some results suggested that patients with ages under 65 years or unmethylated MGMT promoter might have a greater survival benefit from the use of levetiracetam.

CONCLUSIONS

The use of levetiracetam during CCRT in patients with newly diagnosed glioblastoma may result in improved outcomes, but further investigations are warranted.

Effect of Levetiracetam Use Duration on Overall Survival of Isocitrate Dehydrogenase Wildtype Glioblastoma in Adults: An Observational Study

OBJECTIVES

The association between Levetiracetam and survival of Isocitrate Dehydrogenase (IDH) wildtype glioblastomas is controversial. We investigated whether the duration of Levetiracetam use during the standard chemoradiation protocol impacts overall survival of IDH-wildtype glioblastoma patients.

METHODS

Observational single-institution cohort study (2010-2018). Inclusion criteria were: 1) patients ≥18 years old; 2) newly diagnosed supratentorial tumor; 3) histomolecular diagnosis of IDH-wildtype glioblastoma; 4) standard chemoradiation protocol. To assess the survival benefit of Levetiracetam use during the standard chemoradiation protocol (whole duration, part time, and never subgroups), a Cox proportional hazard model was constructed. We performed a case-matched analysis (1:1) between patients with Levetiracetam use during the whole duration of the standard chemoradiation protocol and patients with Levetiracetam use part time or never according to the following criteria: sex, age, epileptic seizures at diagnosis, RTOG-RPA class, tumor location, preoperative volume, extent of resection, and O6-Methylguanine-DNA methyltransferase promoter methylation status. Patients with unavailable O6-Methylguanine-DNA methyltransferase promoter methylation status (48.5%) were excluded.

RESULTS

460 patients were included. The median overall survival was longer in the 116 patients with Levetiracetam use during the whole duration of the standard chemoradiation protocol (21.0 months; 95%CI, 17.2-24.0) than in the 126 patients with part time Levetiracetam use (16.8 months; 95%CI, 12.4-19.0], and in the 218 patients who never received Levetiracetam (16.0 months; 95%CI, 15.5-19.4; p=0.027). Levetiracetam use during the whole duration of the standard chemoradiation protocol (adjusted Hazard Ratio (aHR) 0.69; 95%CI, 0.52-0.93; p=0.014), O6-Methylguanine-DNA methyltransferase promoter methylation (aHR 0.53; 95%CI, 0.39-0.71; p<0.001), and gross total tumor resection (aHR 0.57; 95%CI, 0.44-0.74; p<0.001) were independent predictors of a longer overall survival. After case matching (n=54 per group), a longer overall survival was found for Levetiracetam use during the whole duration of the standard chemoradiation protocol (HR=0.63; 95%CI, 0.42-0.94, p=0.023).

DISCUSSION

Levetiracetam use during the whole standard chemoradiation protocol possibly improves overall survival of IDH-wildtype glioblastoma patients. It should be considered in the anti-tumor strategy of future multicentric trials.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that in individuals with IDH-wildtype glioblastoma, levetiracetam use throughout the duration of standard chemotherapy is associated with longer median overall survival.

How about Levetiracetam in Glioblastoma? An Institutional Experience and Meta-Analysis

Simple Summary

To date, there is a discrepancy regarding the role of antiepileptic drugs on glioblastoma survival. In the present study, based on large institutional cohort and enhanced with a meta-analysis of seven previously published studies, we show a robust association between the perioperative start of levetiracetam treatment with increased overall and progression-free survival in glioblastoma. Our results encourage the initiation of a prospective clinical trial to analyze the antitumor effect of levetiracetam in glioblastoma patients.

Abstract

Despite multimodal treatment, the prognosis of patients with glioblastoma (GBM) remains poor. Previous studies showed conflicting results on the effect of antiepileptic drugs (AED) on GBM survival. We investigated the associations of different AED with overall survival (OS) and progression-free survival (PFS) in a large institutional GBM cohort (n = 872) treated January 2006 and December 2018. In addition, we performed a meta-analysis of previously published studies, including this study, to summarize the evidence on the value of AED for GBM prognosis. Of all perioperatively administered AED, only the use of levetiracetam (LEV) was associated with longer OS (median: 12.8 vs. 8.77 months, p < 0.0001) and PFS (7 vs. 4.5 months, p = 0.001). In the multivariable analysis, LEV was independently associated with longer OS (aHR = 0.74, p = 0.017) and PFS (aHR = 0.68, p = 0.008). In the meta-analysis with 5614 patients from the present and seven previously published studies, outcome benefit for OS (HR = 0.83, p = 0.02) and PFS (HR = 0.77, p = 0.02) in GBM individuals with LEV was confirmed. Perioperative treatment with LEV might improve the prognosis of GBM patients. We recommend a prospective randomized controlled trial addressing the efficacy of LEV in GBM treatment.

Glutamatergic Mechanisms in Glioblastoma and Tumor-Associated Epilepsy

The progression of glioblastomas is associated with a variety of neurological impairments, such as tumor-related epileptic seizures. Seizures are not only a common comorbidity of glioblastoma but often an initial clinical symptom of this cancer entity. Both, glioblastoma and tumor-associated epilepsy are closely linked to one another through several pathophysiological mechanisms, with the neurotransmitter glutamate playing a key role. Glutamate interacts with its ionotropic and metabotropic receptors to promote both tumor progression and excitotoxicity. In this review, based on its physiological functions, our current understanding of glutamate receptors and glutamatergic signaling will be discussed in detail. Furthermore, preclinical models to study glutamatergic interactions between glioma cells and the tumor-surrounding microenvironment will be presented. Finally, current studies addressing glutamate receptors in glioma and tumor-related epilepsy will be highlighted and future approaches to interfere with the glutamatergic network are discussed.

Antiseizure medication in patients with Glioblastoma- a collaborative cohort study

PURPOSE

We investigated, whether epileptic seizures (ES) as presenting symptom in adult patients with GBM are associated with better Overall Survival (OS) compared to ES presenting later during the course of GBM, and efficacy and safety of different antiseizure medications (ASMs).

METHODS

Retrospective consecutive cohort study of adults with GBM: 50 from Norway and 50 from Italy. We compared the time to changing ASM treatments. OS was investigated with a Cox regression model adjusted for time dependency.

RESULTS

Median follow-up was 17 months from GBM diagnosis. ES were the presenting symptom in 49 patients. All patients received ASM treatment. LEV was the first ASM in the majority of patients and the most effective at one year from the first prescription, (p = 0.004). Occurrence of adverse events (AEs) was similar between LEV and other ASMs (p = 0.47). Poorer OS correlated with older age at GBM diagnosis, country and ASM therapy. A negative impact of ASMs on OS was observed for LEV in a univariate and multivariate analysis, and for VPA (only in multivariate analysis), even when adjusted for O6-methylguanine-DNA-methyltransferase (MGMT) methylation status. Patients with ES as the onset symptom of GBM and patients who had first ES later had similar OS (p = 0.87).

CONCLUSION

ES as the GBM debut symptom did not lead to a longer OS. LEV was a more effective ASM compared to other treatments with no differences regarding AEs between LEV and other ASMs. Surprisingly, in our patients LEV and VPA were associated with worse OS than other ASMs. This result should be interpreted with caution due to the retrospective nature of this study along with the many variables which may affect the outcome in this population.

Ion Channels as Therapeutic Targets in High Grade Gliomas

Simple Summary

Glioblastoma multiforme is an aggressive grade IV lethal brain tumour with a median survival of 14 months. Despite surgery to remove the tumour, and subsequent concurrent chemotherapy and radiotherapy, there is little in terms of effective treatment options. Because of this, exploring new treatment avenues is vital. Brain tumours are intrinsically electrically active; expressing unique patterns of ion channels, and this is a characteristic we can exploit. Ion channels are specialised proteins in the cell’s membrane that allow for the passage of positive and negatively charged ions in and out of the cell, controlling membrane potential. Membrane potential is a crucial biophysical signal in normal and cancerous cells. Research has identified that specific classes of ion channels not only move the cell through its cell cycle, thus encouraging growth and proliferation, but may also be essential in the development of brain tumours. Inhibition of sodium, potassium, calcium, and chloride channels has been shown to reduce the capacity of glioblastoma cells to grow and invade. Therefore, we propose that targeting ion channels and repurposing commercially available ion channel inhibitors may hold the key to new therapeutic avenues in high grade gliomas.

Abstract

Glioblastoma multiforme (GBM) is a lethal brain cancer with an average survival of 14–15 months even with exhaustive treatment. High grade gliomas (HGG) represent the leading cause of CNS cancer-related death in children and adults due to the aggressive nature of the tumour and limited treatment options. The scarcity of treatment available for GBM has opened the field to new modalities such as electrotherapy. Previous studies have identified the clinical benefit of electrotherapy in combination with chemotherapeutics, however the mechanistic action is unclear. Increasing evidence indicates that not only are ion channels key in regulating electrical signaling and membrane potential of excitable cells, they perform a crucial role in the development and neoplastic progression of brain tumours. Unlike other tissue types, neural tissue is intrinsically electrically active and reliant on ion channels and their function. Ion channels are essential in cell cycle control, invasion and migration of cancer cells and therefore present as valuable therapeutic targets. This review aims to discuss the role that ion channels hold in gliomagenesis and whether we can target and exploit these channels to provide new therapeutic targets and whether ion channels hold the mechanistic key to the newfound success of electrotherapies.