Prostate cancer caused an estimated 258,000 deaths worldwide in 2008, and is the second most common cause of cancer deaths in males in the USA with approximately 32,000 deaths estimated for 2010. Currently the most effective screening tests available are based on a single biomarker, prostate specific antigen (PSA). Screening for prostate cancer using PSA is controversial as it is known to have low specificity (generally less than 50%), which generates high false positive rates, resulting in many unnecessary surgical and radiotherapy procedures. The development of autoantibodies associated with prostate cancer, and their appearance prior to symptoms in other cancers, makes them attractive as potential biomarkers for early diagnosis of prostate cancer.
OGT has developed the unique Sense Proteomic™ “functional protein” array platform which uses over a thousand correctly folded proteins to detect autoantibodies in prostate cancer serum samples. Using leading-edge data analysis strategies, the company has identified panels of multiple biomarkers which may have clinical utility in the diagnosis of prostate cancer. In this new pilot study presented at the AACR conference, 73 prostate cancer and 60 control samples were used to identify a set of biomarkers which can distinguish prostate cancer from control samples with both sensitivity and specificity above 90% — well above the “standard” for PSA.
Welcoming this promising development, Dr John Anson, OGT’s Vice President of Biomarker Discovery, said: “These initial data are very satisfying, so much so that we have already instigated a major follow-on clinical study involving 1800 samples to further develop and validate the biomarker panel.” The trial has been rigorously-designed, and as well as 400 prostate cancer samples and an equal number of matched normal samples, there are around 150 samples of other cancers and several hundred samples from patients shown to have other diseases of the prostate. The latter can present similar symptoms to prostate cancer and can, in many cases, raise PSA levels and trigger a biopsy. OGT expects its biomarker panel to discriminate between prostate cancer and these ‘interfering’ diseases.
Results from this follow-on study are due in the first half of 2011. “Based on these exciting results and the larger study,” Dr Anson continued “we are assessing partnership opportunities with diagnostic and pharmaceutical companies for the development of a diagnostic test. We are also exploring the extensive potential of our Sense Proteomic functional protein array technology for improving the diagnosis of other cancers and autoimmune diseases.”
For further information on this trial and OGT’s functional protein array technology, as well as background information on existing diagnostics tests for prostate cancer, please visit www.ogt.co.uk/go/prostate
For further information, please contact: Oxford Gene Technology, Begbroke Science Park, Sandy Lane, Yarnton, Oxford OX5 1PF T: +44 (0) 1865 856826 ; F: +44 (0) 1865 848684 ; E: products@ogt.co.uk W: www.ogt.co.uk
About Oxford Gene Technology
Founded by Professor Ed Southern, Oxford Gene Technology (OGT) provides innovative clinical genetics and diagnostic solutions to advance molecular medicine. www.ogt.co.uk.
Biomarker Discovery: OGT has a proven pedigree in genomic technology, which, together with the experience gained through the purchase of Sense Proteomics in 2009, enables OGT to develop highly specific customised genomic and proteomic biomarker panels for cancer and other diseases. OGT develops these for clinical screening and companion diagnostics requirements, both for direct sale and also for collaboration with partner companies.
Early results in prostate cancer, and additional studies in systemic lupus erythematosus (SLE) and non-small cell lung cancer, validate OGT’s functional protein microarray technology for identifying highly-specific and sensitive biomarker panels for a range of cancers and autoimmune diseases.
OGT’s functional protein microarray technology also allows monitoring of immune modulation to therapeutic intervention during clinical trials. This new field of study will allow pharmaceutical companies to identify off-target effects of prospective drugs and the development of companion diagnostics.
Clinical & Genomic Solutions: OGT’s Genefficiency™ is a unique combination of world-leading platforms, people, processing power and performance synchronised to deliver rapid, high quality genomic data to customers worldwide. The OGT CytoSure™ cytogenetics array, labelling and interpretation software products provide a complete solution for the detection of chromosomal abnormalities. Together, Genefficiency and CytoSure offer a unique, standardised and integrated solution for cytogenetics research.
About prostate cancer and PSA
Prostate cancer is the second most common cause of cancer deaths in males in the USA with approximately 220,000 new cases and 32,000 deaths estimated for 2010. Screening using Prostate Serum Antigen (PSA) and digital rectum examination (DRE) has not been proven to be effective in reducing mortality.
Reported specificities for the PSA test vary but in general are much less than 50%. For example, in community practice the PSA cut-off point of 4 ng/ml is considered sensitive but relatively non-specific (sensitivity of 86% and specificity of 33%). A raised PSA level can indicate prostate cancer but it is also seen in other conditions of the prostate such as benign prostatic hypertrophy (BPH) and prostatitis. This poor specificity results in many unnecessary procedures and their associated morbidity.
