Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
A green approach to cancer research Understanding what turns on and turns off apoptosis or cell suicide promises to provide a new range of tools for fighting cancer. Dr Mark Hampton, an HRC Sir Charles Hercus Health Research Fellowship recipient, is part of the Free Radical Research Group at the Christchurch School of Medicine and Health Sciences. Apoptosis should be switched on when something goes wrong in a cell, such as when it gets damaged or begins to grow out of control, Dr Hampton explains. “Unfortunately in a number of cancer cells this pathway gets switched off, and the cell continues to grow.” Dr Mark Hampton Key words: – cancer, apoptosis, drug resistance, isothiocyanates. Key facts about cancer in New Zealand: – 7,674 New Zealanders died of cancer in 1999, more than 20 every day. – a major cause of treatment failure is the development of drug resistance by cancer cells. Aims of our research are to: – characterise the ability of various isothiocyanates to trigger apoptosis in normal cells and cancer cells – discover what proteins are being targeted by isothiocyanates, and how this leads to the induction of apoptosis. What our research has found: – phenethyl isothiocyanate (present in watercress) is able to kill cancer cells that are resistant to a range of chemotherapeutic drugs – a distinct set of thiol proteins are modified in cancer cells treated with isothiocyanates, and these proteins are currently being identified. This resistance to apoptosis also complicates the task of oncologists who find cancer cells can become resistant to chemotherapy as well. The key for Dr Hampton and his colleagues in the Free Radical Research Group is to find compounds that can turn apoptosis on again. They now have a particularly promising group of compounds called isothiocyanates, which are derived from cruciferous vegetables such as watercress, broccoli and wasabi. Isothiocyanates are responsible for the pungency and peppery flavour of these plants. It is already known that isothiocyanates can protect against cancer, and that they can trigger apoptosis. But Dr Hampton’s team has also discovered that one of these compounds can kill drug-resistant cancer cells, and sensitise them to other agents that trigger apoptosis. They intend to look at a range of different isothiocyanates to try and discover the chemical features important for promoting apoptosis. They will also look at the efficacy of crude extracts of cruciferous vegetables to see if they do the same thing. The ability to drive apoptosis may contribute to the cancer preventive properties of these plants. The research team is also studying what is happening at a molecular level inside cells. The goal is to identify the targets of isothiocyanates, and understand how they promote apoptosis in cells. Dr Hampton believes that specialized thiol proteins inside cells are able to control processes like apoptosis and the team has developed a proteomic technique to monitor changes in all the thiol proteins in a cell. “The technique will allow us to identify the molecular targets of the isothiocyanates. This fundamental knowledge will be crucial in working out how isothiocyanates promote apoptosis in cancer cells, and provide a foundation for developing them or related products for use in the clinic.” This research is funded by the Health Research Council of New Zealand, and has also received funding from the Cancer Society of New Zealand, the Marsden Fund, the Canterbury Medical Research Foundation and the University of Otago. HRC39 2004 Level 3, 110 Stanley Street, Auckland PO Box 5541, Wellesley Street, Auckland, NZ Telephone 64 9 303 5200 Facsimile 64 9 377 9988 Website www.hrc.govt.nz Health Research Council of New Zealand Te Kaunihera Rangahau Hauora o Aotearoa