Abstract
Objective: Microparticles are cellular-derived vesicles (0.5-1.0 [mu]m) composed of cell membrane components, which are actively shed from the surface of various cells, including epithelial cells. We compared microparticles in ascites between women with ovarian carcinoma and women with benign ovarian pathology, and isolated tumor-derived (epithelial cell adhesion molecule [EpCAM]-positive) microparticles for functional analysis and proteomics.
Results: Microparticles in benign pelvic fluid were similar to early and advanced-stage ascites (2.4 vs 2.8 vs 2.0 x 106 microparticles/mL). Advanced stage had a greater proportion of EpCAM-positive microparticles than early or benign disease (13.3% vs 2.5% vs 2.1%; P = 0.001), and serous histology had more than endometrioid (13.2% vs 1.8%; P = 0.01).......Conclusions: Ascites from advanced-stage and serous ovarian carcinomas contain large numbers of tumor-derived microparticles. In vitro, these microparticles bind to cancer cells and stimulate migration. Tumor-derived microparticles in ascites could mediate the predilection for peritoneal spread in serous ovarian carcinomas.
