The rate of membrane vesicle shedding by tumor cells is probably related to
their invasive capability. In order to verify whether the vesicle amount c
ould be utilized as a marker of different pathologies, we analyzed biologic
al fluids obtained from 33 patients with gynecological diseases. In fluids
of benign serous cysts, vesicle content was extremely low; in cystoadenomas
and fibromas generally it was low. On the contrary, large amounts of vesic
les were found in malignant tumor fluids. Gelatin zymographies showed the p
resence of MMP-2 and MMP-9 in all vesicles except in those recovered from f
luids of some serous cysts. A positive correlation between tumor malignancy
and both vesicle-amount and vesicle-associated MMP-2 activity was noticed.
We also analyzed vesicle content in ascitic fluids recovered from two carc
inomas at different times during clinical treatment. In both cases, tumor p
rogression, not monitored by Ca 125 levels, was pointed out by an increased
amount of vesicles in ascites. These findings suggest that vesicle content
in biological fluids could represent a new useful marker of tumor aggressi
veness and tumor progression.