Worldwide Cancer Research Menu

Studying how ‘bubbles’ released by glioblastoma (brain) tumours enable them to grow and spread

Dr Kasper Rouschop is studying how 'bubbles' released by glioblastoma (brain) cancer cells encourage blood vessels to grow into the tumour.

Within tumors, areas exist that are exposed to very low levels of oxygen as it is used up by the rapidly growing cells. These are known as 'hypoxic regions' and they contribute to drug and radiotherapy resistance. They also allow the tumour to progress and grow by stimulating new blood vessel development which bring in food supplies, take away waste products, delivers new oxygen to relieve hypoxia and allow cancer cells to enter the blood stream and start secondary tumours elsewhere in the body, known as metastasis.

Dr Rouschop told us "In part, the hypoxic cells facilitate these effects. Recently we identified vesicles, small 'bubbles,' that are involved in the release of factors that promote blood vessel growth. Now we are trying to determine how these vesicles are created, pinpoint what their role is in tumor progression and identify their mechanism of action."

He concluded "We anticipate that the results of this research will enable us to evaluate whether targeting these particular bubbles could be a potential new way to reduce the growth of brain tumours. Our approach is highly innovative and is based on our previous identification of “bubbles” that are specifically released by hypoxic tumour cells. Without the support of Worldwide Cancer Research, evaluation of this promising approach would not be possible.”

Using fruit flies to study how brain tumours develop

Professor Christos Delidakis is studying how brain tumours develop, with the help of fruit flies. Contrary to common belief, insects can get cancer. In fact, with the right genetic tools researchers can create fruit fly tumours with particular defects that mimic those often found to be responsible for human cancers.

Professor Delidakis told us “We plan to use the fruit fly Drosophila to study a tumour model. The advantages of using flies are many – to name a few: easy, cheap and quick to grow in the lab, sophisticated yet exquisitely easy to use genetic tools, compact genome, great ease to isolate and image tissues under the microscope.”

He continued “When a molecular pathway called Notch is over-activated in fly brains, the brains grow to a larger size and consist of masses of cells that do not look like normal nerve cells. Although this reminds us of a brain tumour, it is not known if these enlarged brains are truly malignant. To qualify as such, they have to be able to metastasize (spread around the body) and kill the animal.

We plan to perform experiments to transplant fragments of brains with overactive Notch to healthy flies and ask whether the transplants will metastasize and kill their host.

We will also use modern genomic tools to look in great detail into the number of genes active in healthy vs tumorous brain tissue. Since the human Notch counterpart is deregulated in many cancers, including brain tumours, this research will help us gain a deeper understanding of how Notch works and how it can trigger cancer.”

Hope for children – understanding why some medullablastoma brain tumours don’t respond to chemotherapy

Professor Taylor in Toronto is working to improve standard treatments for an aggressive form of childhood brain tumour.

Medulloblastomas are one of the most common types of brain tumour to affect children and young teenagers. Despite advances in treatment and survival, they still account for around 1 in 10 of all childhood cancer deaths.

“This type of brain tumour can sometimes spread around the brain and spinal cord, making it very difficult for doctors to treat,” explains Professor Taylor. “Conventional treatment consists of a combination of surgery, chemotherapy and radiation therapy, which often successfully shrinks the original tumour but is less effective at controlling the cancer which has spread.”

In this project Professor Taylor and his team want to find out why chemotherapy treatments sometimes don’t work against these medulloblastoma tumours.

“Understanding why medulloblastoma sometimes fails to respond to chemotherapy is key to developing novel and meaningful therapies.” Says Professor Taylor. “Yet this is often a neglected area of brain tumour research.”

“In this study we will search for the tumour genes which make tumour cells and tumours which have spread ‘chemoresistant’, that is, able to survive chemotherapy treatment. If we can unveil the core mechanisms of chemoresistance in medulloblastoma, this knowledge will contribute to the development of better treatments, and ultimately, we hope, improve survival for children with medulloblastoma.”