Estrogen and progestin inhibit invasiveness of gynecologic metastatic cancer cells to blood vessel endothelium.

The Boyden chamber method showed that the invasiveness to reconstituted blood vessel endothelium of metastatic gynecologic cancer cell lines of the uterine cervix (MS751 and ME-180), endometrium (AN3 CA), and ovary (SK-OV-3 and PA-1) was significantly higher than of primary cancer cell lines of the cervix (HeLa and C-33 A), endometrium (Ishikawa, HEC-1-A and HHUA), and ovary (MCAS and Caov-3), and that the invasiveness was inhibited by estradiol or progestin in the metastatic cells but not in the primary cells. These results suggest that metastatic cancer cells by themselves increase the potential of blood vessel invasion, which can be inhibited by estrogen and progestin administration.