Mass spectrometry may improve our ability to diagnose cancer

Endometrial cancer – which affects the lining of the uterus – is the fourth most common form of cancer facing women in Canada. Last year alone, an estimated 3,500 new cases were reported. However, while the numbers are alarming, York Professor Michael Siu, director of the Centre for Research in Mass Spectrometry, and his collaborators are taking steps to help improve the diagnosis and prognosis of this potentially deadly condition.



Right: Michael Siu


“Traditional methods of diagnosing cancer are not perfect,” says Siu, referring to ultrasound, biopsies and the painstaking examination of tissue under microscope. “These methods tend to be very costly and invasive. By using mass spectrometry, however, we may be able to change all of that.”


Mass spectrometry is an analytical technique used to identify the chemical constitution of a substance by separating and weighing that substance’s gaseous ions. By applying mass spectrometry to the field of proteomics, Siu is helping to sequence and identify specific proteins that are involved in endometrial cancer. He expects that these “cancer markers”, once identified, will greatly improve the diagnosis and even prognosis of cancer. In collaboration with Dr. Terence Colgan at Toronto’s Mount Sinai Hospital and Dr. Alexander Romaschin at Toronto General Hospital, Siu and his team have already identified over 10 cancer markers in the last two-and-a-half years.


“Ultimately, we hope to develop a panel or collection of cancer markers,” explains Siu. “This will increase the sensitivity and the selectivity of the diagnosis.”


Siu, a professor of chemistry, is also working on more fundamental research projects. A flourishing collaboration with York chemisty Professor Alan Hopkinson has resulted in a better understanding of the structures and fragmentation mechanisms of peptides – relevant to protein sequencing in mass spectrometry. With Ronald Pearlman, University Professor of biology at York, Siu has identified 223 proteins – many of which are novel and have unknown functions – in the cilia of Tetrahymena thermophila, a member of the protists, a group of organisms that actually make up a greater part of the biosphere than humans. Easy to grow and manipulate, Tetrahymena thermophila can provide researchers with a useful model for explaining the behaviour of other, more complex organisms.


As NSERC/MDS SCIEX Chair, Siu stresses the importance of collaboration with academics, hospitals and industry. His current work involves collaborations with researchers in Toronto, Chicago, Halifax and Connecticut, and he expects that his partnerships will continue to expand.


Among his many distinctions, Siu’s most recent awards include the Spectroscopy Society of Canada’s 2004 Gerhard Herzberg Award as well as a 2002 Award of Merit from the Federation of Chinese Canada Professionals’ Education Foundation. 


This article was submitted to YFile by Jason Guriel, research assistant in the Office of the Vice-President Research & Innovation.