I am regularly asked about the importance of genetic research for brain tumours and how it can help us to develop new treatments and ultimately a cure.  The first lecture at the American Society for Neuro-oncology meeting, which summarised the new World Health Organisation classification of brain tumours published earlier this year, helped to answer this question.

The previous guidelines were published in 2007, so we have obtained a significant amount of information about brain tumours in the interim. The reclassification actually took over four years because of all the new information that had to be taken into consideration.

The key advance is that the classification is no longer based primarily on the pathology of the tumour but now it is combined with the genetic changes in the tumour cells. This allows us to be much more precise in the diagnosis of the tumour which will ensure that the most appropriate drugs are used. Work from the genetic studies carried out by researchers at the Brain Tumour Research-funded centres has contributed to the development of the new classification.

Because of the differences between individual types of brain tumour, it is appreciated that new therapies won’t be appropriate for all tumour types. The information on tumour classification will help to identify those which are more likely to be sensitive to specific therapies. This is called “personalised medicine” and will be a key focus for future drug development.

The results from a number of initial clinical trials of new therapies were announced at the meeting today. Many of these focus on new targets which have been identified following detailed research on tumour samples. While the results from some of the initial trials are encouraging, there is still a way to go before these would be available for use in the clinic. However, it is encouraging to know that trials into new drugs are being carried out.

A number of research presentations focused on changes in how tumour cells generate energy which is a key requirement for them to spread within the brain. This may be a target at which drugs can act to halt tumour progression. But, the development of such drugs requires a detailed understanding of individual tumours and their particular characteristics so that the drug can accurately target the cells.

It is particularly interesting that some trials are being carried out using a combination of drugs. Each drug will interfere with different aspects of the cell function but together, they can have a maximal effect to kill the cells.

While the body’s immune system is designed to recognise “foreign” factors such as bacteria, it should also recognise the changes observed on the surface of tumour cells when they start to grow out of control.

However, tumour calls can prevent the immune system from recognising these changes. Some of the newer therapies under development act to unmask the cells so that they can now be attacked by the immune system. However, the use of an immune-based approach to treat brain tumours has an added problem as the brain has a much less active immune system because of the sensitivity of the nerve cells.

One approach would be to turn up the activity of the brain’s immune system and use this to increase the sensitivity of tumour cells to the action of other drugs. This requires the development of novel tools which have provided a challenge to the researchers. However, a discussion focusing on immune-associated therapies reported a number of novel systems that are being tested. While most of the studies in this area are at a relatively early stage, there are a few which are likely to start in clinical trials in the near future.

So at the end of the meeting’s first day, there are reports that some new treatments are in the development pipeline. However, our detailed understanding of individual tumour types will be essential to ensure that the treatments are used most effectively.

Dr Kieran Breen -Director of Research

Read Part 2 here