Quantification and Purification of Circulating Prostasomes as Diagnostic Tool for Prostate Cancer Detection

Prostate cancer is the most frequently diagnosed cancer among men over 50 years old in Western societies, with an incidence that is steadily increasing in most countries. The current, most commonly used biomarker for prostate cancer is prostate specific antigen (PSA), which has well known limitations in accuracy and requires additional testing. However, prostate cancer cells secrete exosomes, also known as prostasomes, which are only detectable in the blood of prostate cancer patients. The presence of prostasomes in the blood is in itself a prostate cancer diagnosis. However, the assay that has been designed for the purification of prostasomes requires additional testing for evaluating its robustness and usefulness in the clinical setting. Additionally, the evaluation of the cargo of the purified prostasomes may provide more information on the nature of the prostate cancer, which may help develop a molecular assay for a prostate cancer liquid biopsy rather than a tissue biopsy. Therefore, the purpose of this study is two-fold: a validation phase where the purification of prostasomes will be tested on plasma collected from prostate cancer patients and a molecular testing phase where the contents of the purified prostasomes will be evaluated on their ability to determine the grade of the prostate tumors.

We will collaborate with Dr. Masood Kamali-Moghaddam at the Uppsala University (Department of Immunology, Genetics and Pathology) for molecular assay processing.