Revealing prostate cancer heterogeneity – five genetic subtypes identified

Researchers from the Cancer Research UK Cambridge Institute and Addenbrooke’s Hospital (both UK) have discovered five subtypes of prostate cancer and discerned a method to distinguish each of them. The findings, published in EBioMedicine, could lead to advances in the diagnosis of aggressive tumors as well as more personalized therapies for prostate cancer patients.

Samples of healthy and cancerous prostate cancer tissue were taken from more than 250 men and were investigated for abnormal chromosomes and activity of 100 specific genes known to be associated with the disease. From the samples, the researchers reported five genetically distinct subtypes of prostate cancer. The analysis predicted the most aggressive subtypes with more accuracy than current PSA and Gleason score tests, which are used routinely by doctors.

With approximately 41,700 new cases diagnosed every year, prostate cancer is the most common cancer in men in the UK. In addition, 10,800 people die in the UK each year due to the disease.

Malcolm Mason, Cancer Research UK’s prostate cancer expert, commented: “The challenge in treating prostate cancer is that it can either behave like a pussycat – growing slowly and unlikely to cause problems in a man’s lifetime –or a tiger – spreading aggressively and requiring urgent treatment. At the moment we have no reliable way to distinguish them. This means that some men may get treatment they don’t need, causing unnecessary side effects, while others might benefit from more intensive treatment.

“This research could be game-changing if the results hold up in larger clinical trials and could give us better information to guide each man’s treatment – even helping us to choose between treatments for men with aggressive cancers. Ultimately, this could mean more effective treatment for the men who need it, helping to save more lives and improve the quality of life for many thousands of men with prostate cancer.”

Further research will set out to confirm the findings in studies of a larger scale. The team hope to explore the molecular foundations of each identified prostate cancer subtype.

By carrying out more research into how the distinct subtypes behave, scientists may be able to develop more effective ways to treat prostate cancer patients in the future, saving more lives. The findings also have the potential to aid clinical decisions on treatment courses for each individual patient, based on the characteristics of their tumor.

Sources: Ross-Adams H, Lamb AD, Dunning MJ et al. Integration of copy number and transcriptomics provides risk stratification in prostate cancer: A discovery and validation cohort study. EBioMedicine. DOI: 10.1016/j.ebiom.2015.07.017 (2015); Cancer Research UK press release