Prof. Balyasnikova's project is truly game-changing for brain cancer treatment. The development of this novel non-invasive imaging approach is analogous to giving our medical experts a powerful new pair of glasses for the brain, allowing them to witness in real-time how immunotherapy battles GBM. This cutting-edge approach provides a dynamic and detailed view, ensuring quicker and more accurate assessments of treatment effectiveness. By enabling timely adjustments to therapy plans, it not only enhances patient care but also offers the precious gift of time – a crucial factor in the challenging journey against brain cancer. This innovative project represents a significant leap forward, promising a more proactive and effective approach to monitoring GBM and improving outcomes for those facing this formidable disease.

Prof. Balyasnikova's innovative imaging tool promises clinicians and researchers not only a more reliable but also an earlier indication of therapy effectiveness. This ensures timely adjustments to treatment plans, avoiding unnecessary delays. By incorporating an effective early monitoring program, we can provide patients with the gift of time, enabling a seamless transition to alternative therapies and enhancing the proactive and engaging approach to caring for brain cancer patients.

The recent success of immunotherapy in extracranial malignancies has translated into active clinical trials. However, the standard assessment for therapeutic response relies on conventional CT and MRI, both of which detect primary changes in the tumour (e.g., morphology, size) but fail to reflect the molecular alteration induced by immunotherapy, which often translates into subtle modifications at the cellular level directly linked to positive therapeutic response without early morphological manifestations. In this perspective, clinicians often have difficulty differentiating between actual tumour progression and pseudoprogression (i.e., the complex set of changes that mimic actual progression but, in reality, reflect positive therapeutic outcomes). Developing an imaging approach for monitoring immunotherapy response, which can improve the clinical ability to distinguish between the two regimens, represents an unmet clinical need. The proposed study will employ a preclinical framework aiming to monitor immunotherapeutic response in vivo using a multimodality imaging approach, allowing the detection of spatiotemporal changes in the tumour microenvironment with a particular focus on a quantitative regional assessment of early tumoural apoptosis, which plays an essential role in determining therapeutic outcome early before macroscopic morphological manifestations. The specific strength of our preclinical experimental design is in combined quantitative multiparametric MRI with 99mTc-duramycin SPECT (imaging agent targeting apoptosis) to capture the early changes in cellular and molecular tumour microenvironment linked to immunotherapeutic intervention. This approach will allow the visualization and GBM response to immunotherapy, facilitate toxicity monitoring in the surrounding healthy brain tissue, and identify patient responders and non-responders in the clinic.

Such a molecule has never been discovered before for changing the characteristic of a tumour blood vessel. Its potential for treating brain cancers is simply untapped. We know in real world clinical trials, regular immunotherapy does not work in brain cancers, but the addition of antibodies targeting CD93 may hold the key in unleashing the body's immune system to battle brain cancers with minimal side effects.

This project aims to resolve one of the greatest problems in tumour immunotherapy, by allowing infiltration of immune cells into the tumour microenvironment, which will enable other scientists to combine their own immunotherapeutic strategies for the treatment of brain cancers. In essence, this treatment strategy is an enabling tool for other immunotherapy researchers to work on further treatments for brain cancer patients.

Targeting CD93/IGFBP7 axis to normalise tumour vasculature and improve T cell trafficking in human gliomas

Tumour vasculature has been theorised to present chemical and physical impedance to effector T cell trafficking. Recently, Dr Yeung’s research group interrogated gene expression profiles in tumours under the treatment of VEGF inhibitors and identified CD93 as a potential target that mediates vascular normalization. The group identified a novel interaction between CD93 and IGFBP7, both overexpressed in tumour but not normal vasculature, that could be antagonised to improve drug delivery and increase immune infiltration.

Aggressive gliomas displayed poor response to nivolumab (anti-PD1 mAb) and overexpression of the IGFBP7/CD93 pathway has been associated with poor response to anti-PD therapies in other cancers. Blockade of the CD93/IGFBP7 using proprietary antibodies developed by the group successfully turned “cold” tumours into “hot” tumours with increased T cell infiltration in preclinical melanoma and pancreatic cancer models.

VEGF overexpression is commonly found in high-grade and recurrent gliomas so CD93-IGFBP7 would likely be induced in these aggressive tumours. Indeed, CD93 expression was recently found to be highly expressed in GBM vasculature, but not in normal brain vessels.

Targeting the CD93/IGFBP7 axis has the potential to enhance the effects of immunotherapy in malignant gliomas without unwanted side-effects of anti-VEGF therapy as CD93/IGFBP7 is downstream in signalling.

This project combines three game-changing approaches to treating brain cancer: (1) a novel form of radiotherapy – known as FLASH radiotherapy – which uses a rapid, ultra-high dose rate radiotherapy beam. This shortens treatment time and minimises damage to healthy brain tissue (2) injection of a drug-loaded gel (called a hydrogel) into the tumour resection cavity to attack and kill residual cancer cells that could not be surgically removed and (3) the hydrogel loaded with a compound effective at attacking GBM stem cells, the tumour cells responsible for tumour recurrence.

This project aims to show the effectiveness of drug-loaded gel (known as hydrogel) as a therapy for brain cancer patients, and explore the effectiveness of combining the hydrogel treatment with a rapid, high-dose rate radiotherapy technology. For patients, this combined treatment approach has the potential to minimise treatment time for patients while sparing healthy brain tissue damage. Most importantly, the drug compound in this study has already been shown to effectively kill GBM and glioma stem cells known to drive recurrence, meaning this treatment approach may prevent tumour recurrence.

FLASH radiotherapy and radiation-responsive hydrogel drug delivery as a novel combination therapy for glioblastoma

Glioblastoma (GBM) patients, despite an aggressive treatment strategy, invariably have recurrence of the primary tumour, leading to death. Seeking improved treatments for GBM and the potential glioma stem cells (GSCs) implicated in recurrence, the team performed a high-throughput screen of a large bioactive drug library and found that the drug Quisinostat effectively targets GSCs and GBM cells at nanomolar concentrations. The team also tested this drug and confirmed efficacy in patient-derived GBM organoids and in mouse GBM models, however, the team observed dose-limiting systemic side effects. Therefore, the team now seek to leverage their collective expertise to develop a therapeutic strategy centered on administration of a radiation-responsive drug loaded hydrogel (RR-gel) to the tumour resection cavity. Such an approach will result in high concentrations of drug deposited directly to the target site, while avoiding unnecessary systemic doses to other organs. Furthermore, since radiotherapy is also part of the standard of care, a hydrogel that synergizes with radiation (e.g. increases the effects of radiotherapy and/or releases drug in response to radiotherapy) will improve treatment outcomes.

The team’s promising preliminary data shows that such a hydrogel can effectively control GBM tumours. Moreover, the team plans to integrate the hydrogel with FLASH radiotherapy, a novel form of radiotherapy that involves ultra-fast delivery of radiation treatment at dose rates several orders of magnitude higher than those conventionally used and has the potential to decrease normal tissue toxicity. The team proposes to develop improved versions of our radiation-responsive hydrogel system, characterize them and test them in vitro and in vivo for their anti-GBM efficacy, in combination with FLASH radiotherapy. The team will use spectral CT to monitor the hydrogel in vivo. The safety of the treatment will be extensively assessed. Overall, the team seeks to develop a breakthrough therapy for GBM.

Many attempts have been made to analyse short DNA fragments from the blood that are associated with cancer. The critical limitation is that these cancer-associated DNA fragments are very low in concentration, and are hidden amongst a sea of other ‘background’ DNA within the blood. This project takes a game-changing approach by analysing longer DNA fragments and comparing the patterns with thousands of known brain tumours to accurately identify the type of brain tumour. This project will also investigate the DNA content across several blood components such as platelets and white blood cells. This approach has never been tested in childhood brain cancer patients.

This blood test technology aims to help children with brain cancer by providing a non-invasive diagnostic that: (1) identifies those children showing neurological symptoms who need brain scans; (2) assist surgeons in surgical planning; (3) identifies those children who may be able to avoid surgery, since some tumours do not benefit from surgery. In addition, this blood test may potentially show whether a tumour is responding to treatment, and whether it is growing back or not.

Methylation profiling of circulating DNA in paediatric brain tumour patients

Most children with brain tumours first come to medical attention with headaches and other neurological symptoms. Because imaging is expensive, a child is often just treated for their symptoms, hoping they get better, without actually being diagnosed. But sometimes, the disease ends up being a brain tumour. Treating these tumours can be difficult, since the developing brain is very sensitive to neurosurgery, radiation, and chemotherapy. We need an earlier, cheaper, and easier test to reliably diagnose and subclassify paediatric brain tumours. This would not only help identify children who do need brain scans, it would also help neurosurgeons if they knew exactly what kind of tumour they were dealing with while planning surgery. This might even help some children avoid surgery altogether, since some tumours don’t benefit from surgery, or if the blood test says it’s unlikely to even be a tumour. It would also be helpful if that same test could tell whether a tumour is responding to treatment, and whether it is growing back or not.

The Nervous System Tumour Bank at Northwestern University in Chicago recently collaborated with scientists from Toronto to show that a new blood test, called “cell-free methylated DNA immunoprecipitation and high-throughput sequencing” (cfMeDIP-seq), could accurately diagnose the presence and type of brain tumour in adult patients. This technique detects fragments of tumour DNA in the circulating blood, and tests it to see if it matches any pattern of DNA in a large reference library consisting of thousands of brain tumours. While cfMeDIP-seq is already being developed for use in adults with brain tumours, it has not yet been explored in children. Northwestern Medicine, in partnership with Lurie Children’s Hospital of Chicago, has the required technical expertise and paediatric brain tumour patient volume to advance cfMeDIP-seq for the care of children with CNS tumours.

To do this, the team will use laboratory models that incorporate a 'complete' immune system. Having an immune system is essential for testing new immunotherapies, and allows development of brain-specific childhood approaches. This project will study the childhood brain tumour microenvironment, especially the immune compartment, during cancer growth and treatment to uncover the best timing to administer immunotherapy to childhood cancer patients.

This project will develop a new model for testing immunotherapy in the childhood cancer setting. This will help children with brain cancer from three perspectives (1) allowing for identification of more effective childhood cancer-specific treatments (2) improve our understanding of child-specific toxicities and (3) enhance our ability to translate the most effective therapies into the clinic faster.

Using paediatric mice to model paediatric brain tumours

Very few new cancer drugs have been identified for children. We believe this is partially because children are treated as “small adults” in cancer drug discovery. Without exception, cancer drugs are tested in adult clinical trials, with trials in children only performed later, if at all. Furthermore, virtually all preclinical studies have been conducted in adult mice rather than paediatric mice. This completely ignores differences that exist between adults and children in the developmental stage of their brain, immune system, organs, and tumour microenvironment. we will develop world-first techniques to more accurately evaluate new childhood cancer therapies in paediatric mice, rather than in adult mice as is done currently. We hypothesise this will better identify childhood cancer-specific treatments and child-specific toxicities, improving our ability to translate the best therapies into the clinic faster. In particular, our pipeline will enable the testing of promising new immunotherapies in paediatric mice for the first time. Using our paediatric models, we will pioneer the development of preclinical standard-of-care protocols, including radiotherapy, for paediatric mice that mimic clinical protocols. This will then give us clinically-relevant and age-appropriate model systems with which we can overlay and evaluate new immunotherapies, thus expediting their translation to upfront clinical trials. Our long-term vision is that introduction of effective new therapies will afford a reduction in the dose of toxic chemotherapies and radiotherapy currently used for standard-of-care, so that all brain cancer patients can live long, happy, and healthy lives.