For Tableland company EcoBiotics, going back to nature has unearthed the mother lode of all drugs - a possible cancer-fighting molecule, reports GAIL SEDORKIN

Curing cancer is now a quantum leap closer.

A Yungaburra company has conducted successful clinical trials combating cancer using a drug derived from the fruit of a small rainforest tree.

Dr Paul Reddell, co-founder Dr Victoria Gordon and the EcoBiotics team have discovered the rainforest plant with potential life-saving compounds.

"We have already completed a successful clinical trial in horses with a common type of cancer in horses (advanced equine sarcoids) that is untreatable with current methods," he said. "We are now looking to move the drug to testing against obstructive tumours and skin cancers in humans."

The trial with diseased horses produced dramatic results.

"The cancers were the size of a tennis ball to begin and following the injection of this drug have shrunk, died and then fallen out. Finally the skin around the tumour area has healed."

The story behind discovering this new drug started eight years ago when EcoBiotics was founded in Far North Queensland.

"We got an idea and really wanted to try it – to take a risk," he said.

Dr Reddell points out if you go to any pharmacy, more than half the drugs come originally from a molecule that was discovered in nature.

"For instance aspirin was one of the first drugs made and it comes from the bark of willow trees, while taxol (a frontline drug used to treat breast cancer) comes from the North American yew tree," he said.

"Nature doesn’t make chemicals for fun – they are there for a purpose, to allow the organism to survive, compete and defend themselves and reproduce.

"Why not look more closely at how and why they use this chemistry to get smart leads for new drugs?"

Dr Reddell said this was the key to EcoBiotics’ work.

Both formerly with CSIRO, the husband-and-wife team of Dr Reddell and Dr Gordon co-founded the small biotechnology firm in the Atherton Tableland township in 2000. EcoBiotics now also operates out of Brisbane.

The team recently attracted international zebrafish expert Dr Jim Hill from Europe to work in the tropics.

"How did we find our current cancer drug in a rainforest tree? We basically sat down and thought about what were the features that would make a good drug and where would nature make chemicals with these sort of properties," Dr Reddell said.

"In this case the search was for a plant defence compound where the plant basically protects itself against animals that want to make a meal of it."

The drug used for the successful clinical trials was produced in a rainforest fruit, acting as a feeding deterrent to protect the seed.

The active chemical causes mild inflammation in the animal’s mouth, which stops it eating the seed.

It’s this "deterring" or "toxic" quality that caught the team’s eye.

"It won’t kill the animal but it will put it off eating any more," Dr Reddell said.

Once the active chemical is found the next step is to determine if there will be any adverse side effects and again the company looks to nature for help.

Zebrafish are bred in tanks at their laboratory where the eggs are then collected.

The way a zebrafish egg develops over the first few days of its life is quite similar to that of a human embryo, to a certain point, Dr Reddell explained.

"We can see, for instance, whether the drugs will inhibit the massive development of capillaries (which provide tumours with their essential food source).

"We can also tell from how the drug affects the embryo whether it might block migration of cancer stem cells
which is the basis for fighting metastasis (the spread of malignant tumour cells and infections)," Dr Reddell says.

"Anything that is highly toxic gets culled very early in our studies as does anything that produces deformed embryos."

For instance, when thalidomide was tested in the fish embryos, it produced mutation to the limbs by the second day.

EcoBiotics is now offering its zebrafish screening services to other drug companies.

"There’s only four other companies in the world offering this sort of contract research. The others are in the UK, Europe and the US," he said.

"We decided to do what we could do well in the Far North – be close to the rainforest and reef to discover their chemical secrets, tap into a great skill base of local knowledge in our region and adopt new technologies like the zebrafish testing."

When they first founded the business, Dr Reddell took a job with an environmental consulting group within Rio Tinto as their principal ecologist for three years to basically keep the money coming in, while Dr Gordon started full time.

Dr Reddell said EcoBiotics was an unusual combination of science, ideas and business that works but credits Dr Gordon with the business acumen.

EcoBiotics is also unusual in the field in that it was totally private from the start, with support from local shareholders.

Work in the field is usually done at universities and government institutions.

While the big drug companies have pumped massive investment into moving new technology away from nature-derived drugs, it has not been that successful.

"In the past 10 to 15 years they’ve been spending more but getting less new drugs approved," Dr Reddell said.

London-based drug developer Antisoma agreed and in 2006 signed a multi-million dollar licensing agreement with EcoBiotics Ltd to evaluate up to three chemicals discovered in rainforest plants by EcoBiotics.

The work of EcoBiotics also has the support of the Queensland Government, which through the Biodiscovery Act allows the company access to state land to collect plants and berries. Royalties from any successes go back to the Government.

Dr Reddell says only very small quantities of material are initially needed to find new compounds from the rainforest. They then study the molecules to determine if they can be made in a laboratory.

"This is the preferred method for the big drug companies – to put on a white lab coat and make something. But nature is complex and also very subtle," he said.

"So often we find interesting molecules that you can’t make in a laboratory.

"We then look to grow our own supplies from which we can isolate the drug.

"It becomes just like a high-value orchard with the potential to mean another add-on industry here on the Tableland."

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