Hong Kong (PRWEB) April 10, 2009
The Hong Kong Polytechnic University (PolyU) has achieved further breakthrough in developing cancer drugs through making use of advanced biotechnology. This breakthrough not only gives a ray of hope for cancer patients, but also revolutionizes the concept of cancer drug development. This innovation has recently been awarded the Prize of the State of Geneva (third runner-up prize) and a Gold Medal with Jury's Commendation at the 37th International Exhibition of Inventions, New Techniques and Products of Geneva.
Developed by Associate Professor Dr Thomas Leung Yun-chung and Assistant Professor Dr Thomas Lo Wai-hung of the University's Department of Applied Biology and Chemical Technology, the new drugs work on the mechanism of starving cancer cells through depletion of arginine - a key nutrient for many cancer cells.
PolyU researchers have proved that the depletion or lowering of blood arginine concentrations is effective in inhibiting the proliferation of liver cancer. The research paper on this important finding was first published in the authoritative, highly cited journal Cancer Research, published by the American Association for Cancer Research (January 2007 issue). This paper has shed new light on the development of novel arginine-depleting cancer drug for treating liver cancer (hepatocellular carcinoma).
The main constituent of this new drug is arginase, an enzyme that degrades arginine, with urea as an end-product. However, naturally occurring arginase has a very short half-life and thus cannot be used for therapeutic purpose. Using state-of-the-art DNA technology, PolyU researchers produced in 2005 a recombinant human arginase that, after chemical modification, has a significantly prolonged half-life for therapeutic use. More recently, they have further invented a novel drug based on naturally occurring thermostable Bacillus arginase (BCA). A patent application has been filed for this novel drug.
This breakthrough has a far-reaching impact in that the second generation of cancer drugs developed by PolyU researchers could provide a cure not just for liver cancer, but also for other deadly cancer diseases. In the laboratory settings, the new drug has been proved to work in cell culture for breast cancer, cervical cancer, skin cancer, pancreatic cancer, lung cancer, colorectal cancer, and gastric cancer.
Pre-clinical studies conducted on the use of this drug in nude mice showed that the drug is effective in depleting blood arginine and inhibiting breast cancer. The use of this new drug has opened up many new opportunities for effective treatment of different types of cancer. As this anti-cancer therapy is a targeted approach, it only affects cancer cells but not normal cells, causing less side effects than traditional cytotoxic chemotherapy.
Furthermore, the new drug is more stable with a longer blood circulating half-life, which means cancer patients can receive fewer injections of smaller amounts of this drug to achieve the same result. The new drug is also purer because of its homogenous structure and the production cost is expected to be lower because of its simple form.
The first generation of cancer drug based on arginine depletion has been proved to work on liver cancer and is now going through the clinical trial stages with the support of Queen Mary Hospital and the Centre for the Study of Liver Diseases at the University of Hong Kong. The second generation of cancer drugs will also go through similar testing stages in the years ahead.
The discovery of this new drug is supported by research funding from the Lo Ka Chung Charity Foundation and the Simatelex Charitable Foundation. The research work is being undertaken at the University's Lo Ka Chung Centre for Natural Anti-Cancer Drug Development, which was set up in December 2006 with a generous donation of HK$20 million from Mr Lo.
This innovation, together with the descriptions of five other intriguing research projects, are being put on public display at the "PolyU Achievements Exhibition" which runs from 6 to 9 April on the university campus.