Vaccine strategies for glioblastoma: progress and future directions

Therapeutic cell-based vaccines for glioblastoma multiforme

Glioblastoma multiforme (GBM), a highly aggressive tumor, poses significant challenges in achieving successful treatment outcomes. Conventional therapeutic modalities including surgery, radiation, and chemotherapy have demonstrated limited efficacy, primarily attributed to the complexities associated with drug delivery to the tumor site and tumor heterogeneity. To address this critical need for innovative therapies, the potential of cancer vaccines utilizing tumor cells and dendritic cells has been explored for GBM treatment. This article provides a comprehensive review of therapeutic vaccinations employing cell-based vaccine strategies for the management of GBM. A meticulous evaluation of 45 clinical trials involving more than 1500 participants revealed that cell-based vaccinations have exhibited favorable safety profiles with minimal toxicity. Moreover, these vaccines have demonstrated modest improvements in overall survival and progression-free survival among patients. However, certain limitations still persist. Notably, there is a need for advancements in the development of potent antigens to evoke immune responses, as well as the optimization of dosage regimens. Consequently, while cell-based vaccinations show promise as a potential therapeutic approach for GBM, further research is imperative to overcome the current limitations. The ultimate objective is to surmount these obstacles and establish cell-based vaccinations as a standard therapeutic modality for GBM.

The clinical significance of radiological changes associated with gliadel implantation in patients with recurrent high grade glioma

Gliadel occasionally induces edema following its implantation. We aimed to correlate such post-surgical radiological changes to its efficacy and subsequent survival. Fifty-six patients with recurrent high grade glioma were treated between 2005 and 2016 with Gliadel implantation. Volumetric measurements of MRI features, including FLAIR abnormalities, tumor bulk (volume of gadolinium enhancement on T1) and resection cavity volumes over time were conducted. To assess dynamics over time, linear regression trendlines for each of these were calculated and examined to correlate with survival. Median follow-up after resection was 21.5 months. Median survival post-Gliadel implantation and overall survival since diagnosis were 12 months and 22 months, respectively. A subgroup of patients (n = 6) with a transient increase in FLAIR changes volume over time survived significantly longer post-Gliadel compared to those who did not demonstrate such change (36 vs 12 months, p = .03). Positive trends, representing overall growth in volume over time, of tumor bulk and resection cavity predicted survival in multivariate analyses (hazard ratios 7.9 and 84, p = .003 and .002, respectively). Increase in tumor bulk and resection cavity over time were associated with decreased survival, while transient FLAIR increase was a favorable prognostic factor. This may represent a transient inflammatory process in the tumor, possibly stemming from a presumed immune-mediated anti-tumor response.

Identification of Tumor Antigens and Immune Subtypes of Glioblastoma for mRNA Vaccine Development

The use of vaccines for cancer therapy is a promising immunotherapeutic strategy that has been shown to be effective against various cancers. Vaccines directly target tumors but their efficacy against glioblastoma multiforme (GBM) remains unclear. Immunotyping that classifies tumor samples is considered to be a biomarker for immunotherapy. This study aimed to identify potential GBM antigens suitable for vaccine development and develop a tool to predict the response of GBM patients to vaccination based on the immunotype. Gene Expression Profiling Interactive Analysis (GEPIA) was applied to evaluate the expression profile of GBM antigens and their influence on clinical prognosis, while the cBioPortal program was utilized to integrate and analyze genetic alterations. The correlation between antigens and antigen processing cells was assessed using TIMER. RNA-seq data of GBM samples and their corresponding clinical data were downloaded from the Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) for further clustering analysis. Six overexpressed and mutated tumor antigens (ARHGAP9, ARHGAP30, CLEC7A, MAN2B1, ARPC1B and PLB1) were highly correlated with the survival rate of GBM patients and the infiltration of antigen presenting cells in GBMs. With distinct cellular and molecular characteristics, three immune subtypes (IS1-IS3) of GBMs were identified and GBMs from IS3 subtype were more likely to benefit from vaccination. Through graph learning-based dimensional reduction, immune landscape was depicted and revealed the existence of heterogeneity among individual GBM patients. Finally, WGCNA can identify potential vaccination biomarkers by clustering immune related genes. In summary, the six tumor antigens are potential targets for developing anti-GBMs mRNA vaccine, and the immunotypes can be used for evaluating vaccination response.

Temozolomide nano enabled medicine: promises made by the nanocarriers in glioblastoma therapy

Glioblastoma multiforme (GBM) is abnormal cell proliferation of glial cells. GBM is the grade IV glioma brain cancer which is life-threatening to many individuals affected by this cancer. The DNA alkylating agent Temozolomide (TMZ) has the distinctiveness of being FDA approved anticancer drug for the first line treatment for GBM. However, treatment of GBM still remains a challenge. This is attributed to TMZ's toxic nature, severe side effects, and fast degradation in vivo. In addition, the lack of targeting ability increases the chances of systemic toxicities. A nano enabled targeted delivery system not only improves the efficiency of TMZ by making it cross the blood brain barrier, have specificity to target, but also reduces toxicity to healthy tissues. Over the last decade the significant advances in the area of nanotechnology applied to medicine have developed many multifunctional therapeutics. In this context, the present review article comprehends the significant progress in the field of TMZ loaded nanocarriers showing promise for futuristic nanomedicine therapies in treating GBM.

Frontiers in the treatment of glioblastoma: Past, present and emerging

Glioblastoma (GBM) is one of the most aggressive cancers of the brain. Despite extensive research over the last several decades, the survival rates for GBM have not improved and prognosis remains poor. To date, only a few therapies are approved for the treatment of GBM with the main reasons being: 1) significant tumour heterogeneity which promotes the selection of resistant subpopulations 2) GBM induced immunosuppression and 3) fortified location of the tumour in the brain which hinders the delivery of therapeutics. Existing therapies for GBM such as radiotherapy, surgery and chemotherapy have been unable to reach the clinical efficacy necessary to prolong patient survival more than a few months. This comprehensive review evaluates the current and emerging therapies including those in clinical trials that may potentially improve both targeted delivery of therapeutics directly to the tumour site and the development of agents that may specifically target GBM. Particular focus has also been given to emerging delivery technologies such as focused ultrasound, cellular delivery systems nanomedicines and immunotherapy. Finally, we discuss the importance of developing novel materials for improved delivery efficacy of nanoparticles and therapeutics to reduce the suffering of GBM patients.

Combination immunotherapy strategies for glioblastoma

INTRODUCTION

Despite recent advances in treatment for a number of cancers with immune checkpoint blockade (ICB), immunotherapy has had limited efficacy in glioblastoma (GBM). The recent multi-centered CheckMate 143 trial in first time recurrent GBM and the Checkmate 498 trial in newly diagnosed unmethylated GBM showed that antibodies against programmed cell death protein 1 (PD-1) failed to improve overall survival in patients with GBM. Recent preclinical and clinical studies have explored combining ICB with several other therapies including additional ICB against alternative checkpoint molecules, activation of costimulatory checkpoint molecules such as 4-1BB, radiation-induced tumor cell lysis and immunogenic recruitment, local chemotherapy, neoadjuvant ICB therapy, and myeloid cell reactivation.

METHODS

We have reviewed the literature on ICB seminal to the progression of several preclinical studies and clinical trials in order to provide a compendium of the current state of combination immunotherapy for GBM. For ongoing clinical trials without associated publications, we searched clinicaltrials.gov for ongoing studies using the keywords, "GBM" and "glioblastoma", as well as names of checkpoint molecules.

RESULTS

Recent trends from clinical trials demonstrate that despite a variety of different combination strategies involving ICB, GBM remains largely elusive to current immunotherapies. There is a discordance of survival outcomes between GBM pre-clinical models and clinical trials, likely due to the heterogeneity of GBM in patients as well as other adaptive immune mechanisms not otherwise represented in murine models. However, in clinical studies, neoadjuvant ICB in GBM was found to diversify the T cell receptor (TCR) repertoire and increase chemokine mRNA transcripts when comparing pre- and post- surgical time points. Moreover, an increase in peripheral and tumor-infiltrating lymphocyte (TIL) clonotypes were also observed when comparing adjuvant and neoadjuvant cohorts.

DISCUSSION

Despite the lack of clinical survival benefit, immune modulation was observed in multiple different combination strategies for GBM in both preclinical and clinical studies, indicating that ICB combination therapy results in a significant immunological impact on the tumor microenvironment.

High-Density Lipoprotein-Mimicking Nanodiscs for Chemo-immunotherapy against Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is an aggressive primary brain tumor, for which there is no cure. Treatment effectiveness for GBM has been limited due to tumor heterogeneity, an immunosuppressive tumor microenvironment (TME), and the presence of the blood-brain barrier, which hampers the transport of chemotherapeutic compounds to the central nervous system (CNS). High-density lipoprotein (HDL)-mimicking nanodiscs hold considerable promise to achieve delivery of bioactive compounds into tumors. Herein, we tested the ability of synthetic HDL nanodiscs to deliver chemotherapeutic agents to the GBM microenvironment and elicit tumor regression. To this end, we developed chemo-immunotherapy delivery vehicles based on sHDL nanodiscs loaded with CpG, a Toll-like receptor 9 (TLR9) agonist, together with docetaxel (DTX), a chemotherapeutic agent, for targeting GBM. Our data show that delivery of DTX-sHDL-CpG nanodiscs into the tumor mass elicited tumor regression and antitumor CD8+ T cell responses in the brain TME. We did not observe any overt off-target side effects. Furthermore, the combination of DTX-sHDL-CpG treatment with radiation (IR), which is the standard of care for GBM, resulted in tumor regression and long-term survival in 80% of GBM-bearing animals. Mice remained tumor-free upon tumor cell rechallenge in the contralateral hemisphere, indicating the development of anti-GBM immunological memory. Collectively, these data indicate that sHDL nanodiscs constitute an effective drug delivery platform for the treatment of GBM, resulting in tumor regression, long-term survival, and immunological memory when used in combination with IR. The proposed delivery platform has significant potential for clinical translation.

Histone deacetylase enzymes and selective histone deacetylase inhibitors for antitumor effects and enhancement of antitumor immunity in glioblastoma

Glioblastoma multiforme (GBM), which is the most common primary central nervous system malignancy in adults, has long presented a formidable challenge to researchers and clinicians alike. Dismal 5-year survival rates of the patients with these tumors and the ability of the recurrent tumors to evade primary treatment strategies have prompted a need for alternative therapies in the treatment of GBM. Histone deacetylase (HDAC) inhibitors are currently a potential epigenetic therapy modality under investigation for use in GBM with mixed results. While these agents show promise through a variety of proposed mechanisms in the pre-clinical realm, only several of these agents have shown this same promise when translated into the clinical arena, either as monotherapy or for use in combination regimens. This review will examine the current state of use of HDAC inhibitors in GBM, the mechanistic rationale for use of HDAC inhibitors in GBM, and then examine an exciting new mechanistic revelation of certain HDAC inhibitors that promote antitumor immunity in GBM. The details of this antitumor immunity will be discussed with an emphasis on application of this antitumor immunity towards developing alternative therapies for treatment of GBM. The final section of this article will provide an overview of the current state of immunotherapy targeted specifically to GBM.

Anti-PD-1 antitumor immunity is enhanced by local and abrogated by systemic chemotherapy in GBM

The immunosuppressive effects of chemotherapy present a challenge for designing effective cancer immunotherapy strategies. We hypothesized that although systemic chemotherapy (SC) exhibits negative immunologic effects, local chemotherapy (LC) can potentiate an antitumor immune response. We show that LC combined with anti-programmed cell death protein 1 (PD-1) facilitates an antitumor immune response and improves survival (P < 0.001) in glioblastoma. LC-treated mice had increased infiltration of tumor-associated dendritic cells and clonal expansion of antigen-specific T effector cells. In comparison, SC resulted in systemic and intratumoral lymphodepletion, with decreased immune memory in long-term survivors. Furthermore, adoptive transfer of CD8⁺ cells from LC-treated mice partially rescued SC-treated mice after tumor rechallenge. Last, the timing of chemo- and immunotherapy had differential effects on anti-PD-1 efficacy. This study suggests that both mode of delivery and timing have distinct effects on the efficacy of anti-PD-1. The results of this work could help guide the selection and scheduling of combination treatment for patients with glioblastoma and other tumor types.

Tumor Vaccines for Malignant Gliomas

Despite continued research efforts, glioblastoma multiforme (GBM) remains the deadliest brain tumor. Immunotherapy offers a novel way to treat this disease, the genetic signature of which is not completely elucidated. Additionally, these tumors are known to induce immunosuppression in the surrounding tumor microenvironment via an array of mechanisms, making effective treatment all the more difficult. The immunotherapeutic strategy of using tumor vaccines offers a way to harness the activity of the host immune system to potentially control tumor progression. GBM vaccines can react to a variety of tumor-specific antigens, which can be harvested from the patient's unique pathological condition using selected immunotherapy techniques. This article reviews the rationale behind and development of GBM vaccines, the relevant clinical trials, and the challenges involved in this treatment strategy.

Developing Therapies for Brain Tumors: The Impact of the Johns Hopkins Hunterian Neurosurgical Research Laboratory

The Johns Hopkins Hunterian Neurosurgical Laboratory at the Johns Hopkins University School of Medicine was created in 1904 by Harvey Cushing and William Halsted and has had a long history of fostering surgical training, encouraging basis science research, and facilitating translational application. Over the past 30 years, the laboratory has addressed the paucity of brain tumor therapies. Pre-clinical work from the laboratory led to the development of carmustine wafers with initial US Food and Drug Administration (FDA) approval in 1996. Combining carmustine wafers, radiation, and temozolomide led to a significant increase in the median survival of patients with glioblastoma. The laboratory has also developed microchips and immunotherapy to further extend survival in this heretofore underserved population. These achievements were made possible by the dedication, commitment, and creativity of more than 300 trainees of the Hunterian Neurosurgical Laboratory. The laboratory demonstrates the beneficial influence of research experience as well its substantial impact on the field of biomedical research.

Immunotherapy for glioma: from illusion to realistic prospects?

There is now evidence that the rules established for tumor immunology and immunotherapy in general are relevant for brain tumors. Treatment strategies explored have mainly involved vaccines using either tumor cells or components, and vaccines with defined synthetic peptides. This latter approach offers the advantage to select well-characterized antigens with selective or preferential expression on glioma. This is a prerequisite because collateral damage to the brain is not allowed. A second strategy which is reaching clinical trials is T cell therapy using the patients' own lymphocytes engineered to become tumor reactive. Tumor specificity can be conferred by forced expression of either a high-avidity T cell receptor or an antitumor antibody (the latter cells are called chimeric antigen receptors). An advantage of T cell engineering is the possibility to modify the cells to augment cellular activation, in vivo persistence and resistance to the tumor immunosuppressive milieu. A direct targeting of the hostile glioma microenvironment will additionally be required for achieving potent immunotherapy and various trials are assessing this issue. Finally, combining immunotherapy with immune checkpoint inhibitors and chemotherapy must be explored within rigorous clinical trials that favor constant interactions between the bench and bedside. Regarding immunotherapy for glioma patients, what was an unrealistic dream a decade ago is today a credible prospect.

Vaccine therapies in malignant glioma

Glioblastoma is a grade IV astrocytoma that is widely accepted in clinical neurosurgery as being an extremely lethal diagnosis. Long-term survival rates remain dismal, and even when tumors undergo gross resection with confirmation of total removal on neuroimaging, they invariably recur with even greater virulence. Standard therapeutic modalities as well as more contemporary treatments have largely resulted in disappointing improvements. However, the therapeutic potential of vaccine immunotherapy for malignant glioma should not be underestimated. In contrast to many of the available treatments, vaccine immunotherapy is unique because it offers the means of delivering treatment that is highly specific to both the patient and the tumor. Peptide, heat-shock proteins, and dendritic cell vaccines collectively encapsulate the majority of research efforts involving vaccine-based treatment modalities. In this review, important recent findings for these vaccine types are discussed in the context of ongoing clinical trials. Broad challenges to immunotherapy are also considered.

Brain Tumor Immunotherapy: What have We Learned so Far?

High grade glioma is a rare brain cancer, incurable in spite of modern neurosurgery, radiotherapy, and chemotherapy. Novel approaches are in research, and immunotherapy emerges as a promising strategy. Clinical experiences with active specific immunotherapy demonstrate feasibility, safety and most importantly, but incompletely understood, prolonged long-term survival in a fraction of the patients. In relapsed patients, we developed an immunotherapy schedule and we categorized patients into clinically defined risk profiles. We learned how to combine immunotherapy with standard multimodal treatment strategies for newly diagnosed glioblastoma multiforme patients. The developmental program allows further improvements related to newest scientific insights. Finally, we developed a mode of care within academic centers to organize cell-based therapies for experimental clinical trials in a large number of patients.

Glioblastoma multiforme: Pathogenesis and treatment

Each year, about 5-6 cases out of 100,000 people are diagnosed with primary malignant brain tumors, of which about 80% are malignant gliomas (MGs). Glioblastoma multiforme (GBM) accounts for more than half of MG cases. They are associated with high morbidity and mortality. Despite current multimodality treatment efforts including maximal surgical resection if feasible, followed by a combination of radiotherapy and/or chemotherapy, the median survival is short: only about 15months. A deeper understanding of the pathogenesis of these tumors has presented opportunities for newer therapies to evolve and an expectation of better control of this disease. Lately, efforts have been made to investigate tumor resistance, which results from complex alternate signaling pathways, the existence of glioma stem-cells, the influence of the blood-brain barrier as well as the expression of 0(6)-methylguanine-DNA methyltransferase. In this paper, we review up-to-date information on MGs treatment including current approaches, novel drug-delivering strategies, molecular targeted agents and immunomodulative treatments, and discuss future treatment perspectives.

PI3K pathway inhibitors: potential prospects as adjuncts to vaccine immunotherapy for glioblastoma

Constitutive activation of the PI3K pathway has been implicated in glioblastoma (GBM) pathogenesis. Pharmacologic inhibition can both inhibit tumor survival and downregulate expression of programmed death ligand-1, a protein highly expressed on glioma cells that strongly contributes to cancer immunosuppression. In that manner, PI3K pathway inhibitors can help optimize GBM vaccine immunotherapy. In this review, we describe and assess the potential integration of various classes of PI3K pathway inhibitors into GBM immunotherapy. While early-generation inhibitors have a wide range of immunosuppressive effects that could negate their antitumor potency, further work should better characterize how contemporary inhibitors affect the immune response. This will help determine if these inhibitors are truly a therapeutic avenue with a strong future in GBM immunotherapy.

New strategies in glioblastoma: exploiting the new biology

Glioblastoma is one of the deadliest human cancers. There have been few significant therapeutic advances in the field over the past two decades, with median survival of only about 15 months despite aggressive neurosurgery, radiotherapy, and chemotherapy. Nevertheless, the past 5 years has seen an explosion in our understanding of the genetic and molecular underpinnings of these tumors, leading to renewed optimism about potential new therapeutic approaches. Several of the most promising new approaches include oncogenic signal transduction inhibition, angiogenesis inhibition, targeting canonical stem cell pathways in glioblastoma stem cells, and immunotherapy. As promising as many of these approaches appear, they have not had an impact yet on the natural history of the disease or on patient long-term outcomes. Nevertheless, it is hoped that with time such approaches will lead to more effective treatments, but issues such as the unique biology and anatomy of the central nervous system, impaired drug delivery, poor preclinical models with resultant nonpredictive preclinical screening, and poor clinical trial design potentially impede the rapid development of such new therapies. In this article, we review the excitement and challenges that face the development of effective new treatments that exploit this new biology.

Immunotherapeutic advancements for glioblastoma

Immunotherapy seeks to improve the body’s immune response to a tumor. Currently, the principal mechanisms employed are: (1) to improve an aspect of the immune response (e.g., T cell activation) and (2) to encourage the targeting of particular antigens. The latter is typically achieved by exposing the immune system to the antigen in question, in vivo, or in vitro followed by re-introduction of the primed cells to the body. The clinical relevance of these approaches has already been demonstrated for solid tumors such as melanoma and prostate cancer. The central nervous system was previously thought to be immune privileged. However, we know now that the immune system is highly active in the brain and interacts with brain tumors. Thus, harnessing and exploiting this interaction represents an important approach for treating malignant brain tumors. We present a summary of progress in this area, focusing particularly on immune-checkpoint inhibition, vaccines, and T cell engineering.

Peptide vaccines for the treatment of glioblastoma

Glioblastoma multiforme (GBM) is an extremely malignant brain tumor for which current therapies do little to remedy. Despite aggressive treatment with surgery, radiation therapy, and chemotherapy, tumors inevitably recur as a direct consequence of the infiltrative nature of GBM. The poor prognosis of patients with GBM underscores the clear and urgent need for more precise and potent therapies. Immunotherapy is emerging as a promising means to treat GBM based on the immune system's capacity to mediate tumor-specific cytotoxicity. In this review, we will discuss the use of peptide vaccines for the treatment of GBM. The simplicity of peptide vaccines and their ability to elicit tumor antigen-specific immune responses make them an invaluable tool for the study of brain tumor immunotherapy.

Recent advances in the role of toll-like receptors and TLR agonists in immunotherapy for human glioma

Gliomas are extremely aggressive brain tumors with a very poor prognosis. One of the more promising strategies for the treatment of human gliomas is targeted immunotherapy where antigens that are unique to the tumors are exploited to generate vaccines. The approach, however, is complicated by the fact that human gliomas escape immune surveillance by creating an immune suppressed microenvironment. In order to oppose the glioma imposed immune suppression, molecules and pathways involved in immune cell maturation, expansion, and migration are under intensive clinical investigation as adjuvant therapy. Toll-like receptors (TLRs) mediate many of these functions in immune cell types, and TLR agonists, thus, are currently primary candidate molecules to be used as important adjuvants in a variety of cancers. In animal models for glioma, TLR agonists have exhibited antitumor properties by facilitating antigen presentation and stimulating innate and adaptive immunity. In clinical trials, several TLR agonists have achieved survival benefit, and many more trials are recruiting or ongoing. However, a second complicating factor is that TLRs are also expressed on cancer cells where they can participate instead in a variety of tumor promoting activities including cell growth, proliferation, invasion, migration, and even stem cell maintenance. TLR agonists can, therefore, possibly play dual roles in tumor biology. Here, how TLRs and TLR agonists function in glioma biology and in anti-glioma therapies is summarized in an effort to provide a current picture of the sophisticated relationship of glioma with the immune system and the implications for immunotherapy.

Clinical efficacy of tumor antigen-pulsed DC treatment for high-grade glioma patients: evidence from a meta-analysis

BACKGROUND

The effectiveness of immunotherapy for high-grade glioma (HGG) patients remains controversial. To evaluate the therapeutic efficacy of dendritic cells (DCs) alone in the treatment of HGG, we performed a systematic review and meta-analysis in terms of patient survival with relevant published clinical studies.

MATERIALS AND METHODS

A total of 409 patients, including historical cohorts, nonrandomized and randomized controls with HGG, were selected for the meta-analysis.

RESULTS

The treatment of HGG with DCs was associated with a significantly improved one-year survival (OS) (p<0.001) and 1.5-, 2-, 3-, 4-, and 5-year OS (p<0.001) compared with the non-DC group. A meta-analysis of the patient outcome data revealed that DC immunotherapy has a significant influence on progression-free survival (PFS) in HGG patients, who showed significantly improved 1-,1.5-, 2-, 3- and 4-year PFS (p<0.001). The analysis of Karnofsky performance status (KPS) demonstrated no favorable results for DC cell therapy arm (p = 0.23).The percentages of CD3+CD8+ and CD3+CD4+ T cells and CD16+ lymphocyte subset were not significantly increased in the DC group compared with the baseline levels observed before treatment (p>0.05), whereas CD56+ lymphocyte subset were significantly increased after DC treatment (p = 0.0001). Furthermore, the levels of IFN-γ in the peripheral blood of HGG patients, which reflect the immune function of the patients, were significantly increased after DC immunotherapy (p<0.001).

CONCLUSIONS

Thus, our meta-analysis showed that DC immunotherapy markedly prolongs survival rates and progression-free time, enhances immune function, and improves the efficacy of the treatment of HGG patients.

Vaccine therapies for patients with glioblastoma

Glioblastoma (GBM) is a high-grade glial tumor with an extremely aggressive clinical course and a median overall survival of only 14.6 months following maximum surgical resection and adjuvant chemoradiotherapy. A central feature of this disease is local and systemic immunosuppression, and defects in patient immune systems are closely associated with tumor progression. Immunotherapy has emerged as an important adjuvant in the therapeutic armamentarium of clinicians caring for patients with GBM. The fundamental aim of immunotherapy is to augment the host antitumor immune response. Active immunotherapy utilizes vaccines to stimulate adaptive immunity against tumor-associated antigens. A vast array of vaccine strategies have advanced from preclinical study to active clinical trials in patients with recurrent or newly diagnosed GBM, including those that employ peptides, heat shock proteins, autologous tumor cells, and dendritic cells. In this review, the rationale for glioma immunotherapy is outlined, and the prevailing forms of vaccine therapy are described.

Advances in diagnostic and treatment modalities for intracranial tumors

Intracranial neoplasia is a common clinical condition in domestic companion animals, particularly in dogs. Application of advances in standard diagnostic and therapeutic modalities together with a broad interest in the development of novel translational therapeutic strategies in dogs has resulted in clinically relevant improvements in outcome for many canine patients. This review highlights the status of current diagnostic and therapeutic approaches to intracranial neoplasia and areas of novel treatment currently in development.