Introduction: Prostate cancer (PCa) is the most common malignant tumour and the second leading cause of death among males in Western countries. The current challenges for PCa research are that there are no suitable biomarkers for PCa accurate diagnosis, risk stratification and predicting or monitoring metastasis. Extracellular vesicles and particles (EVPs), secreted by all kind of cells, enriched in nucleic acids, lipids, and proteins from parent cells, with a tremendous potential, including the large extracellular vesicles, small extracellular vesicles, two new nano-sized non-membrane particles called exomeres and supermeres. EVPs hod promise for PCa diagnosis, risk progression stratification and monitoring metastasis.
Methods:The selected PCa patients and health correcponding people were divided into four groups (control, low risk, intermediate risk, high risk, metastasis. N=3 in each group) following the 2017 American Joint Committee on Cancer guideline. PCa cell lines including PC3, LNCaP and 22Rv1, and a normal prostate epithelial cell line RWPE-1 were cultured for EVPs isolation. All EVPs were isolated by UC and then characterised by transmission electron microscopy, nanoparticle tracking analysis and western blotting, atomic force microscopy, zeta potential analyzer and nano-flowcytometry. LC-MS/MS proteomics was carried out to profile the EVPs' proteins.
Results: We have successfully established a method for isolating EVP sub-populations from a group of PCa cell lines and human PCa plasma samples. we comprehensively conbined 6 different methods to characterised EVPs’ properties. Several panels of new EVP protein biomarkers have been identified and the validation and functional study are ongoing in our laboratory.
Key words: EVPs, biomarkers.