A NOVEL APPROACH TO PROSTATE CANCER BIOMARKER DISCOVERY

Prostate cancer (PCa) is the second most common cancer in men worldwide and the sixth most common cause of death. Current screening for PCa consists of monitoring serum prostate-specific antigen (PSA), together with digital rectal examination. The US Preventive Services Task Force concluded that PSA offers little to no benefit when considered together with low specificity and the risk of illness or death from overtreatment. Clearly, new biomarkers are needed for PCa screening. Microscopic vesicles called exosomes are secreted from nearly every cell in the body. Exosomes possess unique mixtures of proteins, RNA and lipids specific for their cell of origin, which has made them the subject of much excitement in biomarker research. To date, exosome biomarker discovery has focused on proteins. Lipids, despite being more abundant and also displaying tissue specificity, have received little attention, since they have been difficult to study in the past. Using lipid mass spectrometry, in which we are experts, we will identify prostasomal lipids from patient samples that are specifically associated with the presence and/or grade of underlying PCa. Our proposed research is unique in the PCa field and on the cutting edge of biomarker research and development.