Shining a light on cancer

The Australian Synchrotron is being built at Monash, and the university's scientists are preparing themselves by becoming heavily involved in research that will make the most of this vital tool. PENNY FANNIN reports on a project that aims to identify brain tumour types more accurately, making treatment easier.

The human brain is considered the last frontier of biology. Despite years of research, many aspects of this vital organ remain poorly understood. But what is known is that the most common malignant tumours of the brain tend to be spread out, making them difficult to remove.

Their diffuseness also means that attacking these brain tumours with conventional cancer treatments such as surgery and radiotherapy is vexed because these treatments damage healthy brain tissue.

Dr Karen Siu.

But Dr Karen Siu, an Australian Synchrotron Research Program Fellow in the School of Physics and Materials Engineering at Monash, is working towards a test that will identify brain tumours more accurately, making treatment easier.

She is starting by using synchrotron radiation to identify structural differences between healthy and cancerous brain tissue.

Dr Siu is focusing on a specific type of brain tumour - gliomas - that are the most common type and of which a subtype, the astrocytomas, are the most malignant.

"The structural characterisation of brain tumours could help us better identify tumour types and give us an improved understanding of how the tumours spread. This could lead to more effective treatment regimes for patients," she says.

The project follows on from research by Monash's professor of X-ray and synchrotron physics, Rob Lewis, into the structural changes that occur in cancerous breast tissue.

A synchrotron is a particle accelerator that uses high-energy electrons to create bright pinpoint beams of light (synchrotron radiation). These high-intensity light beams allow scientists to examine the structure of matter down to the level of atoms and have been used by Professor Lewis to investigate cancerous and non-cancerous breast tissue.

"In cancerous breast tissue, the extra-cellular matrix (the scaffolding that holds cells together) breaks down as the cancer progresses. For the cancer to spread it has to break down this scaffolding," Dr Siu says.

"X-ray scattering is a good probe of this breakdown as it is sensitive to the highly ordered molecules of the extra-cellular matrix. We want to see if we can observe differences, similar to those seen in the breast, between healthy and non-healthy brain tissue."

Dr Siu is using a technique called small angle X-ray scattering to study up to 200 tissue samples taken from patients with brain tumours.

"We hope the technique will give us more information on how brain tumours progress and allow us to distinguish the different types of tumours more accurately," she says.

The project is part of an international collaboration with neurosurgeon Dr Elisabeth Schultke from the University of Saskatchewan in Canada and neurosurgeon Professor Andrew Kaye from the Royal Melbourne Hospital.

"The use of synchrotron radiation is important, as is it gives the best possible data. We're not using it to solve the structure of cancerous versus non-cancerous tissue but to identify certain features that are unique to diseased brain tissue," Dr Siu says.

"Ultimately, we hope that statistical analysis of these features will form the basis of a diagnostic test to identify brain tumours and lead to improved patient outcomes."

Dr Siu will conduct her research over the next three years at four synchrotrons - Daresbury Laboratory in the UK, Elettra in Italy, SPring-8 in Japan and the Advanced Photon Source in Chicago.

The Australian Synchrotron is being built at Monash's Clayton campus and is expected to be operational in 2007.

Construction company Thiess is designing and constructing the building to house the main synchrotron machine. Work began on the building in September.

Action: For more information, contact Dr Karen Siu on +61 3 9905 3646 or email karen.siu@spme.monash.edu.au.