The high expression of CD40/CD40L can be used as a biomarker for better prognoses in patients with gliomas. Immunotherapy using FGK45 significantly prolonged survival and represents a potential therapeutic strategy for gliomas including glioma-initiating cells.

BackgroundGlioblastoma is the most malignant human brain tumor and has a dismal prognosis; however, some patients show long-term survival. The interaction between the costimulatory molecule OX40 and its ligand OX40L generates key signals for T-cell activation. The augmentation of this interaction enhances antitumor immunity. In this present study, we explored whether OX40 signaling is responsible for antitumor adaptive immunity against glioblastoma and also established therapeutic antiglioma vaccination therapy.MethodsTumor specimens were obtained from patients with primary glioblastoma (n = 110) and grade III glioma (n = 34). Quantitative polymerase chain reaction (PCR), flow cytometry, and immunohistochemistry were used to analyze OX40L expression in human glioblastoma specimens. Functional consequences of OX40 signaling were studied using glioblastoma cell lines, mouse models of glioma, and T cells isolated from human subjects and mice. Cytokine production assay with mouse regulatory T cells was conducted under hypoxic conditions (1.5% O2).ResultsOX40L mRNA was expressed in glioblastoma specimens and higher levels were associated with prolonged progression-free survival of patients with glioblastoma, who had undergone gross total resection. In this regard, OX40L protein was expressed in A172 human glioblastoma cells and its expression was induced under hypoxia, which mimics the microenvironment of glioblastoma. Notably, human CD4 T cells were activated when cocultured in anti-CD3-coated plates with A172 cells expressing OX40L, as judged by the increased production of interferon-γ. To confirm the survival advantage of OX40L expression, we then used mouse glioma models. Mice bearing glioma cells forced to express OX40L did not die during the observed period after intracranial transplantation, whereas all mice bearing glioma cells lacking OX40L died. Such a survival benefit of OX40L was not detected in nude mice with an impaired immune system. Moreover, compared with systemic intraperitoneal injection, the subcutaneous injection of the OX40 agonist antibody together with glioma cell lysates elicited stronger antitumor immunity and prolonged the survival of mice bearing glioma or glioma-initiating cell-like cells. Finally, OX40 triggering activated regulatory T cells cultured under hypoxia led to the induction of the immunosuppressive cytokine IL10.ConclusionGlioblastoma directs immunostimulation or immunosuppression through OX40 signaling, depending on its microenvironment.Electronic supplementary materialThe online version of this article (doi:10.1186/s12943-015-0307-3) contains supplementary material, which is available to authorized users.

Local delivery of FGK45 significantly prolonged survival in glioma stem cell models. Thus, local delivery of this monoclonal antibody is promising for immunotherapy against gliomas.

After introduction of levetiracetam (LEV), treatment of seizures in patients with malignant brain tumors has prominently improved. On the other hand, we still experience some cases with LEV-uncontrollable epilepsy. Perampanel (PER) is a noncompetitive a -amino-3-hydroxy-5-methyl-4-isoaxazolepropionate acid receptor antagonist that has recently been approved for treating focal epilepsy as a secondary drug of choice. Available literature reporting PER medication in patients with gliomas is still sparse. Here, we report our initial experience with glioma patients and report efficacy of adding low dose 2-4 mg PER to LEV in patients whose seizure were uncontrollable with LEV monotherapy. Clinical outcome data of 18 consecutive patients were reviewed. This included nine males and nine females aged 24-76 years (median, 48.5 years), treated for glioma between June 2009 to December 2018. We added PER to patients with LEV-uncontrollable epilepsy. Adverse effects, irritability occurred in two patients, but continuous administration was possible in all cases. Though epileptic seizures occurred in four cases receiving 2 mg PER, 17 cases achieved seizure freedom by dose increments; final dose, 2-4 mg PER added to LEV 500-3000 mg. Our study revealed anti-epileptic efficacy of low dose PER 2-4 mg as first add-on therapy to LEV in glioma patients who have failed or intolerable to LEV monotherapy. Low dose PER added on to LEV may have favorable efficacy with tolerable adverse effects in glioma patients with LEV-uncontrollable epilepsy.