Personalized Medicine Targets Prostate Cancer’s Genetic Signatures
Research Advances In some prostate cancers, treatments fail and the goal switches from cure to prolonging life. Investigators are looking at more targeted therapies from the start.
Improved understanding prevents under-treatment
When it comes to prostate cancer treatment, one size doesn’t fit all.
Traditionally, many patients would be handled similarly. The size of their tumour and its appearance under a microscope would dictate treatment, explains Dr. Paul Boutros, Assistant Professor, Medical Biophysics at the University of Toronto, and Principal Investigator at the Ontario Institute for Cancer Research (OICR).
However, that meant many patients with a good prognosis would be over-treated, with a loss of quality of life. More problematic, many other patients at risk of their cancer recurring were under-treated.
“Everybody gets excited about new therapies,” says Dr. Boutros. “But curing cancer won’t just come from new drugs. It will come from using techniques as effectively as possible.”
A big part of that is personalized medicine. By improving their understanding of the unique characteristics of the patient and disease, doctors can customize treatment.
"Curing cancer won’t just come from new drugs. It will come from using techniques as effectively as possible.”
Identifying which cancers respond to treatment
Some highly promising research in personalized medicine is happening through CPC-GENE (the Canadian Prostate Cancer Genome Network). The goal: crack the prostate cancer genetic code, to predict when a treatment might fail.
OICR and Prostate Cancer Canada are part of the CPC-GENE project, which will sequence the genomes of 350 intermediate-risk prostate cancers. This will identify genetic signatures in cancers that do and don’t respond to treatment, and see how the cancer’s makeup varies in each individual’s prostate.
CPC-GENE is one of 67 projects in 17 jurisdictions that are part of the International Cancer Genome Consortium. Together, these projects are sequencing 25,000 tumour genes.
"Some highly promising research in personalized medicine is happening through CPC-GENE (the Canadian Prostate Cancer Genome Network). The goal: crack the prostate cancer genetic code, to predict when a treatment might fail."
The significance of sequencing
What is the significance of the sequencing? Dr. Rob Bristow, lead Principal Investigator on CPC-GENE Project, uses the analogy of an infection. Sometimes, standard drugs don’t work because the bacteria are resistant. So you try another medicine. That’s why it’s critical to determine those genetic signatures, says Dr. Bristow, a Clinician-Scientist at Toronto’s Princess Margaret Cancer Centre.
He says one-third of intermediate-risk patients need additional treatment, beyond the standard image-guided radiotherapy and surgery to remove the prostate.“Instead of allowing patients to go through all other treatments first,” says Dr. Bristow, “we can understand the genetics with such clarity that we can intensify treatment for a cure.”