Kiwi scientists are making big strides in the field of cancer medicine, revealing two new drug advances yesterday which could reduce the side effects of traditional treatments.
A team from the Auckland Cancer Society Research Centre (ACSRC) and Maurice Wilkins Centre for Molecular Biodiversity, based at the University of Auckland, has designed a new compound that starves certain cancer cells of glucose, depriving them of energy.
The potential of the compound, STF-31, has been demonstrated in the laboratory through a collaboration with researchers from the Stanford University School of Medicine.
The findings were published in Science Translational Medicine.
“Standard cancer therapies attack healthy tissue as well as cancer cells, causing side effects that can limit treatment,” said associate professor Michael Hay.
“By designing new drugs that target some of the abnormal biological processes unique to cancer cells, it may be possible to fight cancer with minimal side effects.”
He said many cancerous cells underwent a change in metabolic process and did not produce energy efficiently, becoming "addicted" to glucose.
“Using STF-31 we have shown that it is possible to selectively inhibit the ability of certain cancer cells to take up glucose. This starves them of energy and causes them to die. Importantly, treatment with STF-31 did not appear to cause toxicity in normal cells and so presages a novel way to selectively target cancer cells.”
Professor Rod Dunbar, director of the Maurice Wilkins Centre, said New Zealand had an outstanding international reputation in biomedical science.
"This is another example of how our scientists are advancing understanding of major diseases and developing innovative new ways of combating them."
The research focused on renal cell carcinoma, the most common form of kidney cancer in adults that is resistant to standard chemotherapy.
Screening at Stanford University identified a simple compound capable of selectively killing renal cell carcinoma. Medicinal chemists at the ACSRC in New Zealand then created a series of drugs for testing.
A series of biological experiments showed STF-31 almost halved the amount of glucose taken up by renal cell carcinoma tumours in mice, and significantly slowed tumour growth.
Hay said the approach could potentially be used to treat a broad range of cancers.
Meanwhile, a “stealth” anticancer drug has also been developed by a separate group of ARSRC and Maurice Wilkins scientists.
PR610 will be clinically developed thanks to an agreement between US-based Proacta Incorporated and Tokyo company Yakult Honsha.
It is part of a pipeline of hypoxia-activated pro-drugs licensed to pharmaceutical firm Proacta by the University of Auckland.
Along with PR509, it targets the low-oxygen (hypoxic) conditions found in many solid tumours. Since they are inactive in healthy tissues, they avoid the problem of indiscriminate toxicity associated with standard cancer treatments.
Proacta granted Yakult research, development and commercialisation rights to the first agent in its class, PR509, in Japan in February.
Both PR509 and PR610 have been targeted for development in non-small cell lung cancer that is resistant to established treatments. They are also likely to be evaluated in other cancers such as gastric, breast, and pancreatic cancer.
“All New Zealanders have an interest in cancer drug discovery and development. We should take pride in seeing such a breakthrough occurring and being led by our local scientific community,” said John Loof, Cancer Society chief executive.