New research by Liverpool University team has revealed a protein marker that identifies aggressive cancers. Prostate cancer is the fifth most common cancer worldwide. Many men who have this disease can live with their cancer untreated for several years - but in others, the cancer spreads aggressively and the prognosis is poor.

In what has proved to be one of the largest studies of its kind, a team of researchers from the Trans-Atlantic Prostate Group (comprising groups from Liverpool University, Kings College and the Memorial Sloan Kettering Centre etc) identified a population of 4,000 patients diagnosed with prostate cancer and studied them over 15 years to find out more about the natural history of this disease.

Although doctors have used the Gleason scoring system to get some idea of how aggressive a prostate cancer is, we do not yet have an accurate test on which we can base a decision on whether a particular cancer needs aggressive treatment or can be managed conservatively and treated expectantly.

The results of one aspect of the study by the Translantic Prostate Group were published in the British Journal of Cancer in August this year, and revealed (among other facts) that a blood test to differentiate aggressive from non-aggressive forms of prostate cancer could well become a possibility in the not too distant future.

The team, led by Professor Chris Forster (head of the division of Pathology at Liverpool University in England) took samples of prostate tissue from a well defined cohort of 553 men who had conservatively managed prostate cancer and analysed the tissue in these samples for the presence of a protein termed Hsp-27.

They found that those samples of prostate cells which showed the presence of the Hsp27 protein came from patients in whom the disease was more aggressive. In fact, during the 15-year period of follow-up, the study showed that those men who tested positive for Hsp-27 at the time of diagnosis were almost twice as likely to die from prostate cancer than men who did not have this protein.

In simple terms, the presence of this biomarker Hsp-27 was an accurate and independent predictor of aggressive disease with poor clinical outcome.

The study also showed that in more than 60% of prostate cancers the Hsp-27 protein was not expressed. These cancers could therefore be managed by careful monitoring ("watchful waiting") rather than with interventions such as drug treatment or surgery.

Explained Professor Chris Foster, the main author of the research paper: "We have identified a link between the presence of Hsp-27 at diagnosis and a lower survival rate for prostate cancer. Our study shows that this protein marker – currently found in tissue samples - can give us a reliable and accurate indication of whether individual cancers will become aggressive. Currently, we are working on developing this finding into a blood test to monitor men with prostate cancer in order to determine when their individual disease needs treatment."

He added "Cancer of any kind is a very distressing disease, having the ability to impact on every aspect of a person’s life. Chemotherapy and surgery can also have a significant effect on health and wellbeing and that is why it is important that we first understand the biological nature of the disease and how it will behave in each individual patient before determining if and when a person needs a particular type of treatment.

"By studying the disease in a large number of men throughout the UK and over a long period of time, we have been able to get a more complete picture of how to manage the disease successfully, whilst limiting the negative impact it can have on a patient’s life. Our study also demonstrates the role of modern Pathology, not only in establishing diagnoses but in determining if the subsequent management of individual patients is biologically appropriate for their particular condition.’’

The newly identified biomarker Hsp27 provides doctors with a signal that a patient’s prostate cancer will continue to progress - and once a prostate cancer is found to express this biomarker, such a patient needs active treatment to kill the cancer cells.