Australian biomarker research headlines international conference

Researchers have moved a step closer to a new and better blood test to diagnosis mesothelioma.

A team from the Asbestos Disease Research Institute in Sydney have discovered a small molecule that is present in far higher levels in the blood of people with mesothelioma than those unaffected by the disease.

The research was the headline presentation at the 3rd European Lung Cancer Conference in Geneva last month, where Dr Michaela Kirschner spoke of the ADRI team’s search for a biomarker, or biological marker, for early diagnosis of the disease.

The team focused on microRNAs, small molecules that are vital to gene regulation, discovering that one, known as miR-625-3p, was four times more abundant in the blood of mesothelioma patients.

To date, soluble mesothelin-related (SMR) protein, discovered by Perth scientist Professor Bruce Robinson and his team in 2004, remains the best available biomarker for mesothelioma. But it is not accurate enough for routine use and patients still need to have a lung biopsy before they can be diagnosed.

Scientists believe that the right biomarker could be the key to detecting mesothelioma early enough to give sufferers a fighting chance of survival. At present, the disease’s long latency period means that by the time sufferers experience symptoms, the disease has often progressed too far for meaningful treatment. A simple blood test would also mean that large numbers of people who have been exposed to asbestos could be screened easily and relatively cheaply.

In two independent trials of miR-625-3p, the ADRI team was able to detect the disease with an accuracy of 82.4 per cent. SMR protein has an accuracy of about 50 per cent.

ADRI researcher Glen Reid says larger trials are needed to discover if the molecule is, in fact, more accurate than observed.

“We used up all the samples we had (in the trials) so we are now searching internationally for more through collaborations,” Dr Reid says. “Even though mesothelioma is a pronounced problem, it is still a rare enough disease that bio-samples can be hard to find in larger quantities.”

The team has joined forces with Prof Robinson and Prof Bill Musk from the National Centre for Asbestos Related Diseases on the project and their research has been published in the current edition of The Journal of Thoracic Oncology.
In another presentation by Australian researchers at the European Lung Cancer Conference, researchers from Melbourne showed that high-dose radiotherapy may help some advanced mesothelioma sufferers.

Researchers from Austin Health Radiation Oncology Centre, led by Dr Malcolm Feigen, gave radiotherapy to 45 patients, none of whom had surgery to remove their affected lung.

The median survival for the patients was 12.4 months from starting radiotherapy, ranging from 2 to 87 months. There were no life-threatening toxicities from treatment.

Dr Feigen said new radiotherapy techniques enabled high doses to be given safely, giving many patients a treatment option to surgery.

By Catherine Madden.