Scientists have developed a test that studies genetic patterns in blood cells to detect advanced?stage prostate cancer. The study shows that gene patterns in blood cells act as a barcode and could be used together with the current PSA test to select those patients with the worst prognosis in need of immediate treatment.
Advanced stage prostate cancer is a very heterogeneous illness in its symptomatology and evolution. Some patients live with it for several years without showing any symptoms, whilst in other cases the tumour can be very aggressive and deadly. This heterogeneity highlights the need to develop reliable tests that discriminate between the different types of patients.
In this study, led by David Olmos from M?laga and Johann de Bono from ICR and The Royal Marsden, the researchers demonstrate that the signs prostate cancer leaves in the blood can be used to further understand the illness. David Olmos has just joined CNIO to set up the Prostate Cancer Clinical Research Unit.
The study described in the article consists of sampling the genetic changes in the patient’s blood. These changes can be interpreted as barcodes to identify those patients who are going to suffer an aggressive form of the cancer. Using the results, doctors could adjust treatment to the specific profile of each patient.
In order to carry out the study, the scientists scanned all the genes in the blood samples of 100 patients with prostate cancer; 69 patients were suffering from an advanced stage of prostate cancer and 31 patients has a localised, low-risk tumour.
Using statistical models, the researchers split the patients into four groups that reflected the different genetic activity patterns?what we have described above as barcodes. After following the patients for approximately two-and-a-half years, the authors observed that one of these groups of patients had a much lower survival rate.
This group had a barcode that can be summed up as showing alterations in the activity of nine genes, and an alteration in the different functions of the immunological system, which suggests that the cancerous cells unleash an anomalous immune response as they multiply in the body.
The authors of the study confirmed these results with 70 additional patients from the Memorial Sloan Kettering Cancer Centre in New York who were also suffering from advanced stage prostate cancer. These results show that this nine-gene barcode can be useful and precise in identifying those patients with the worst prognosis.
“The test we have developed is simpler and potentially more precise than many other tests we currently have available or than carrying out another biopsy”, say the researchers in their study.
The authors of this study plan to evaluate this new test in large-scale clinical trial that will analyse the efficiency of a new drug for treating prostate cancer. Other studies, led by CNIO researchers, will also analyse the utility of these blood tests in patients at early stages of the illness.
David Olmos, the study’s lead researcher, joined CNIO last September to head CNIO’s Prostate Cancer Clinical Research Unit. Olmos previously worked at the Institute for Cancer Research (ICR) and The Royal Marsden NHS Foundation Trust in London, where the study was carried out. David Olmos has made very important contributions to the study of prostate cancer, working with the development of new biomarkers for tracking the illness and the development of phase I, II and III clinical trials for new drugs, some of which have recently been approved for treating the illness.
Source: Centro Nacional de Investigaciones Oncologicas, Madrid