ABSTRACT
@# Objective: To investigate the effects of prostate cancer exosomes on the migration and invasion ability of stromal cells (WPMY-1), and to explore its mechanism. Methods: Exosomes in LNCaP-AI+F prostate cancer cell supernatant were isolated by ultracentrifugation and the typical structure of exosome was captured by electron microscope. The particle size distribution was analyzed by Zetaview, and Wb was used to identify the marker proteins and other proteins.After co-incubation of WPMY-1 cells and prostate cancer exosomes (40 µg/ml), laser confocal microscope was used to observe the uptake of PKH67-labeled exosomes by WPMY-1 cells; Transwell assay was used to detect the migration and invasion ability of WPMY-1 cells; qPCR was performed to detect the expression of three cancer-associated fibroblast (CAF)-related molecules (IL-8, PDGFB and MMP9) at mRNA level; and the phosphorylation of EGFR and ERK1/2 was analyzed by Wb. Results: Typical cup-shaped structure of exosomes was observed under electron microscope. The Zetaview results showed that the particle size distribution was concentrated at about 100 nm. The expression of exosome marker proteins CD63 andALIX further verified that the isolated particles were exosomes. Besides, EGFR, HER2 and SRC, which were related to the progression of prostate cancer, were also enriched in exosomes. After co-incubation, confocal microscope imaging showed a number of PKH67 labeled exosomes in recipient WPMY-1 cells. Transwell experiments showed that exosomes could significantly enhance the migration and invasion ability of WPMY-1 cells (all P<0.01). Compared with the control group, increased secretion of IL-8, PDGFB and MMP9 was observed after exosome treatment (40 µg/ml) (P<0.05 or P<0.01). Wb indicated that exosomes could promote the phosphorylation of EGFR and ERK1/2 of WPMY-1 cells (P<0.01). Conclusion: Prostate cancer cell exosomes could act on the stromal cell WPMY-1 to highly express multiple CAF-related molecules, promote the phosphorylation of EGFR and ERK1/2 and enhance the migration and invasion ability of WPMY-1 cells.