Novel markers for prostate cancer
Diagnosis of prostate cancer is largely based on testing positive for the prostate-specific antigen (PSA). This is increases the rate of over-detection without necessarily correlating with cancer symptoms. Apart from the role of androgens in the development of prostate cancer, the effect of molecular mechanisms such as non-coding ribonucleic acids (ncRNAs) is unknown. The EU-funded 'Prostate cancer: Profiling and evaluation of ncRNA' (PROSPER) project proposed to explore the role of ncRNAs (regulators of key cellular mechanisms) in prostate cancer. Project members will also evaluate the potential use of ncRNAs in diagnostic and prognostic tools as well as therapy targets. As a first step, scientists performed global microRNA (miRNA) expression analysis in prostate cancer samples, which led to the discovery of 20 novel miRNAs. Microarray analyses of miRNAs in over 180 prostate cancer samples indicated that androgens and/or the androgen receptor were instrumental in regulating expression of some miRNAs. Androgen signalling models verified the impact of androgen signalling on miRNA expression and also located androgen receptor binding sites near some of these miRNAs. For prognostic and diagnostic purposes, PROSPER scientists identified a panel of 25 and 56 miRNAs, respectively, to distinguish between normal and prostate cancer samples. miRNAs with oncogenic or tumour suppressor activity in prostate cancer were also identified. The prognostic and diagnostic miRNA panels developed during PROSPER could significantly improve the clinical diagnosis of prostate cancer and reduce unnecessary patient treatment. They also opened up new avenues for drug design and therapeutic exploitation.