Reaching out to a new understanding of cancer

Cancer expert Dr Mark Shackleton, from the University of Melbourne and the Peter MacCallum Cancer Centre, has been named the 2012 Prime Minister’s Prize for Life Scientist of the Year.

Dr Shackleton, a Senior Fellow in the University’s Department of Pathology and the Sir Peter MacCallum Department of Oncology, was awarded the $50,000 prize for his work on breast cancer and melanoma and how this new paradigm is changing our understanding of how cancers grow and resist treatment.

Dr Shackleton graduated from the University of Melbourne in 1992 with a Bachelor of Medicine, Bachelor of Surgery and all he ever really wanted to be, was a doctor – and to cure cancer. However, after years of specialty training as a medical oncologist, he was left disappointed at the lack of progress in cancer research and poor survival rates for some patients. His desire to improve outcomes for patients inspired him to return to basic science.

“I have a problem seeing how millions of dollars are spent on advances that provide only two or three months of extra survival to patients. A 22-year-old with cancer wants 50 more years, not just a few months. So I really wanted to do something brand new, to contribute in a way that was more fundamental than prescribing drugs too often of limited efficacy. What impresses me about basic science is its power to change history. Its potential impact is quite staggering,” Dr Shackleton says.

In his PhD studies on breast cancer at the Walter and Eliza Hall Institute of Medical Research (WEHI) in Melbourne, Dr Shackleton demonstrated for the first time that an entire solid organ – a functioning breast – could be grown from a single cell, a stem cell. He thus proved that, although rare, stem cells exist in solid organs and contribute importantly to normal organ function.

In post-doctoral studies at the University of Michigan on melanoma, Dr Shackleton showed that a high proportion of the cells in these tumours – at least one in four – is capable of producing cancerous offspring. This meant that instead of trying to seek out and destroy rare cancer stem cells, effective treatments for melanoma needed a ‘scorched earth’ policy, attempting to kill as many tumour cells as possible.

In 2010, a Victorian Endowment for Science, Knowledge and Innovation (VESKI) Fellowship facilitated his return to Melbourne, to further his work at the University of Melbourne and at the Peter MacCallum Cancer Centre. 

At the Peter MacCallum Cancer Centre in Melbourne, Dr Shackleton is now studying the organisation of tumours and tracing their development in patients. In doing this, he is testing another theory, clonal evolution – the idea that tumours evolve and change by natural selection of the cells in them. What he is finding is that melanoma cells can mutate surprisingly quickly and easily – perhaps explaining the rapid spread of this disease in patients and why melanoma notoriously becomes resistant to drugs. This evolutionary nature of cancer makes the job of finding cures much more complex – possibly requiring different approaches altogether.

Dr Shackleton says he is delighted to have won this prestigious award.

“I pay tribute to my research team and to all cancer patients. Cancer is a disease of enormous complexity and we still have much to learn.

“This award will allow me to advance research in this new and exciting area. I am investing in research that has huge implications for the development of new cancer treatments that provide lasting benefit to patients.”

Professor James McCluskey, University of Melbourne Deputy Vice-Chancellor Research, congratulated Dr Shackleton. “This is a wonderful achievement which reflects years of hard work that has a real and immediate impact on the quest to understand and control cancer-related diseases. The accolade is a welcome acknowledgement of the depth of research across the University and our affiliates.”

www.mdhs.unimelb.edu.au