ELIZABETH FINKEL

CANCER researchers at Hadassah University Hospital in Jerusalem and The Royal Melbourne Hospital in Melbourne are joining forces to pioneer a blood-based test for detecting brain cancer.

Not only will the technique facilitate monitoring the disease in patients, it will speed the introduction of new therapies.

Andrew Kaye, professor of surgery at the University of Melbourne and director of The Royal Melbourne Hospital department of neurosurgery, said: “This will totally change the way we evaluate cancer therapies for brain tumours.”.

To translate scientific research into cures, researchers need to share their expertise and their patients. That is exactly what Kaye is up to with Professor Tali Siegal and Dr Iris Lavon, who visited RMH earlier this month.

Siegal, a neurologist-researcher, is Director of Hadassah’s neuro-oncology centre; Lavon heads the research laboratory. The pair are paying Kaye a return visit after he and other Melbourne researchers visited Hadassah Hospital in April as part of Hadassah Australia’s AUSiMED Initiative.

While many types of cancers are yielding to modern therapies, brain cancer has remained one of the most resistant. Part of the problem is that researchers do not have a sensitive way to monitor their treatments.

Unlike the lung or bowel, it is extremely hard to get an accurate picture of what is going on in the brain. The mainstay technique, MRI, is a blurred lens. Not only is it unable to detect tumours less than 5mm in size, it fails to distinguish between tumours and local inflammation. This becomes a problem in the follow-up period after chemotherapy and radiotherapy.

A suspicious shadow on an MRI scan often turns out to be inflammation not cancer, meaning the patient has been put through risky surgery for no reason. “Many times we have a dilemma, we have endless arguments,” says Siegal

A blood-based test to detect brain cancers is “the holy grail”, says Kaye. Often cancers do leave clues to their existence in the bloodstream; they shed cells, proteins or even DNA. In prostate cancer, for instance, the protein PSA is used as a marker for the cancer. But so far there is no equivalent for brain cancer.

Hadassah and RMH are forging a partnership in this quest. Kaye’s laboratory has focussed its efforts on cells that can sprout into blood vessels, so-called endothelial cells. In patients with cancer, these cells are commonly found circulating through the bloodstream and might provide the hoped-for “marker” for brain cancer.

On a different front, Hadassah researchers are developing a test to detect the DNA of cancer cells.

As Lavon explains, cancers not only grow more prolifically than other cells, they also die more prolifically. When cancer cells disintegrate some of the debris ends up in the bloodstream as DNA. Like a fingerprint, the DNA of a cancer cell is specific for that cancer. For instance a type of brain cancer known as oligodendroglioma tends to lose particular bits of its DNA in specific regions of chromosomes 1 and 19. Another known as glioblastoma tends to lose methyl groups from a gene called MDMT.

Over the past three years Lavon tested these DNA markers in blood samples and in brain tissue specimens of patients. She was indeed able to detect the same DNA signature in the brain tissue and the bloodstream of the patient, results that will be published shortly in the journal Neuroncology.

Now the key question is: how early can these blood-borne DNA signatures be detected in the course of the disease? To answer that question as quickly as possible, the Jerusalem and Melbourne researchers are combining forces to recruit 250 patients with newly diagnosed brain cancer. RMH technicians will extract DNA from their blood and brain tissue, as per Lavon’s instructions, and send the samples to her Jerusalem lab for DNA testing.

For these combatants against brain cancer this is just the beginning of a powerful strategic alliance. “I see great synergies that can be developed; this is the first step,” says Kaye.

Dr Elizabeth Finkel is a cofounder and contributing editor of Cosmos magazine. She holds a PhD in biochemistry and spent 10 years as a professional research scientist before becoming a journalist and author.