Abstract

Exosomes: Novel Opportunities for the Diagnosis and Therapy of Cancer

Lucia R. Languino, Professor of Cancer Biology, Thomas Jefferson University

Our studies have revealed a role for Integrins in mediating extracellular vesicle (EV) functions.  We have demonstrated a cross-talk between prostate cancer cells and monocytes that promotes pro-tumorigenic M2 polarization.  We have shown that this cross-talk is mediated by the alphavß6 integrin in EVs and have suggested that inhibition of this integrin and its downstream effectors might offer a novel immune – based therapeutic strategy in prostate cancer.  We also demonstrate that the EVs circulating in plasma from prostate cancer patients contain higher levels of a different integrin, alphavß3, and CD9 as compared to plasma EVs from age-matched subjects who are not affected by cancer.  We show that the EVs present in plasma from prostate cancer patients contain higher levels of alphavß3 and CD9 as compared to plasma EVs from age-matched subjects who are not affected by cancer. Furthermore, using PSMA antibody-bead mediated immunocapture, we show that the alphavß3 integrin is expressed in a subset of EVs characterized by PSMA, CD9, CD63, and an epithelial-specific marker, Trop-2.  Our results suggest that detecting alphavß3 integrin in prostate cancer patient EVs could be a clinically useful and non-invasive biomarker to follow prostate cancer progression.