Prostate cancer is the most common cancer in Canadian men and while it has been the focus of extensive research, an estimated 4,000 Canadians die of the disease each year. That is why six years ago Dr. Paul Boutros and Dr. Rob Bristow set out to sequence the normal and diseased tissue of 350 patients and learn from a clinical perspective how genomic information can be used to guide better treatment.

After many years of hard work the Canadian Prostate Cancer Genome Network (CPC-GENE), co-led by Boutros and Bristow, has completed the planned genome sequencing and is publishing results that are poised to improve the treatment of prostate cancer by personalizing therapy for individual patients. The CPC-GENE project is part of the International Cancer Genome Consortium and is funded by Prostate Cancer Canada and OICR.

This research was important in helping us to understand how we should be analyzing tumours to personalize treatment

“This project was different from a lot of the efforts you see in genome sequencing, since there is such a clinical focus to it,” explains Boutros. “People working on the project had to understand both the technical aspects of genome sequencing and analysis as well as the treatment of prostate cancer in the clinic.” Boutros says that exceptional graduate students and trainees were essential to bridging this gap.

One of those trainees, Dr. Emilie Lalonde, published a first paper describing a novel technique to use both genomics and the tumour’s microenvironment to establish a more accurate prognosis. “This research was important in helping us to understand how we should be analyzing tumours to personalize treatment,” says Boutros. “It goes hand-in-hand with our other recent major paper where we looked at why mistakes are made in the use of tests in the clinic.”

In this second paper Boutros, Bristow and collaborators across Canada reported that differences within tumours are partially responsible for biomarkers not always being as accurate and useful as possible. “We found that differences within the tumour mean that a single biopsy will not tell the whole story,” explains Boutros. “Multiple biopsies are needed to get an accurate picture of the patient’s prostate cancer and in turn provide better treatment through personalization.” He says that their data suggests 10 – 15 per cent of patients have two genetically distinct tumours in their prostate and this highlights the difficulty in personalizing treatment.

Boutros and Bristow plan to continue to build upon the findings of these papers and validate their work using large cohort studies. “We are excited to keep adding to our understanding of prostate cancer and to make a push to see that our work is used in the clinic. Armed with this improved understanding of the disease we can offer better diagnostic and prognostic tools that will enhance treatment for prostate cancer patients,” says Bristow.