Each year in New Zealand, around 3000 women and 20 men are diagnosed with breast cancer. Photo / 123RF
Each year in New Zealand, around 3000 women and 20 men are diagnosed with breast cancer. Photo / 123RF
A Kiwi-led project could create a new generation of drugs to combat the biggest killer of breast cancer patients.
Each year in New Zealand, around 3000 women and 20 men are diagnosed with breast cancer, and the principal cause of death remains the spread of primary tumours to other parts of the body.
In the past 15 years, there have been nearly 40 phase-three clinical trials of drugs to counter this incurable process, called metastasis.
Yet, just a dozen of those drugs were approved, of which only four had been supported by results showing longer survival times.
Dr Olga Zubkova, of Victoria University's Ferrier Research Institute, suspects a breakthrough could lie in a specific enzyme that plays an influential role in metastasis.
Heparanase weakens the "glue" that holds cells together, enabling cancer cells to escape through tissue barriers.
"This means the primary tumour can grow faster, enter the circulation and spread to remote parts of the body, becoming very difficult to treat," Zubkova said.
"This tissue invasion makes heparanase a promising drug target."
Zubkova has been investigating heparanase with research that has drawn funding support from the Breast Cancer Foundation New Zealand, and more recently, the Ministry of Business, Innovation and Employment's Endeavour Fund.
"Our research aims to combat heparanase by developing a new generation of anti-cancer drugs that inhibit the enzyme," she explained.
"Standard anti-cancer drugs kill rapidly dividing cancer cells but also affect normal cells and have adverse toxic side effects.
"Cancer treatments frequently employ combinations of drugs with different mechanisms of action. Our goal is to contribute an important new drug to the mix, but one with lower side effects"
Such compounds would provide a framework to exploit what she described as "Velcro-type" interactions for bio-molecular recognition.
"Traditional drug discovery has focused on small-molecule drugs that attach to a single binding site on their target, however biological targets are large molecules," she said.
After seven years of groundwork, she is finally focusing on bringing her promising innovation to fruition.
The project brings together an impressive team of experts from across New Zealand, as well as Canada, Israel, Singapore and the UK.
Dr Olga Zubkova with her Victoria University colleague, Emeritus Professor John Miller. Photo / Supplied
One team led by Victoria University's Emeritus Professor John Miller, a widely-recognised leader in cancer research, will test the compounds in human breast cancer cell lines.
After selecting the best ones for treatment, Dr Anne Barnett of the university's subsidiary Viclink, would push the new class of drugs toward commercialisation.
"The model of drug development is changing," she said.
"Traditionally, large pharmaceutical companies developed their own pipeline of compounds and focused on a few blockbuster products.
"We are now entering a new era of partnerships and alliances between big pharma and smaller companies and universities that are valuable sources of innovative compounds and drug development services."
Because of this, Zubkova said, New Zealand is set to capitalise on having both a strong biomedical research community, and a resourceful society that encourages innovation.
She expects their work wouldn't just benefit breast cancer patients, but also those battling prostate, liver and brain cancers.
Further, she said, the compounds would complement therapies patients were already receiving.
"This will be, potentially, beneficial for preventing a relapse in women with breast cancer that is in remission," she said.
"We hope it will pave the way for long-term treatment with fewer cumulative toxicities, improved patient quality of life, better tolerance and cost–effectiveness."
