Researchers at the Brain Tumour Research Centre of Excellence at Imperial College, London have discovered a potential new treatment which could dramatically improve the effectiveness of radiotherapy for patients diagnosed with the most common and deadliest form of brain tumour.
Scientists found that a drug which depletes the amino acid arginine made glioblastoma multiforme (GBM) tumours much more susceptible to radiotherapy. The research has been published in a paper in the Journal of Clinical Investigation.
Hugh Adams, our Head of Stakeholder Relations, said: “This is a significant and exciting finding. There is an urgent need for novel approaches to treat GBM which, in the majority of cases, is fatal. There have been no improvements to treatment options for this type of tumour in two decades.
“Despite the promise of new targeted approaches in cancer treatment, the standard of care for patients with GBM remains unchanged - surgical resection followed by radiotherapy and chemotherapy.”
Arginine is an amino acid used in the production of complex molecules called proteins, which conduct a vast range of functions within cells. It is required by a variety of cancer cells, especially ones that are growing quickly, and therefore depriving tumours of this amino acid has been explored as a potential anti-cancer strategy in a variety of tumour types, including GBM.
Whilst 70% of GBM tumours are able to make arginine, 30% are not. In this study, the research team focused on the tumours that can make arginine by exposing them to a drug called ADI-PEG20. This drug degrades arginine and the aim was to deprive tumours from access to arginine. The team is also exploring the potential for using ADI-PEG20 in the 30% of tumours that are not able to make arginine. If successful, this would mean that all GBM patients could be treated with arginine depletion.
Dr Nel Syed, who leads the team at Imperial, said: “Arginine is a vital nutrient for tumour growth and our results show that reducing its supply makes tumours much more susceptible to radiotherapy. Removing arginine removes tumour immunosuppression and we found our approach meant immune cells around the tumour were more likely to attack and remove tumour cells.”
“Laboratory results showed that, using the drug ADI-PEG20 in combination with radiotherapy, led to a durable response with extended disease-free survival with no significant toxicity. The next steps are to explore the safety and effectiveness of using this in humans by setting up a new clinical trial.”
Our Director of Research, Policy and Innovation, Dr Karen Noble, explains what this could mean for patients on our blog. Read more here.
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