The effects of oncostatin M on trophoblast cells: influence on matrix metalloproteinases-2 and -9, and invasion activity.

Oncostatin M (OSM), a cytokine of the interleukin-6 (IL-6) family, can either promote or inhibit cell growth in various normal and tumor cells and is expressed in rheumatoid arthritis, multiple sclerosis, multiple myeloma, and other inflammatory conditions. We investigated one of the possible mechanisms involved in trophoblast invasion using the human placental cell line derived from first trimester extravillous trophoblasts (HTR8SVneo): modulation of matrix metalloproteinase (MMP)-2 and -9 expression and enzymatic activity. And we addressed also the effects of exogenous OSM on the in vitro invasion activity of HTR8SVneo cells. We found that OSM enhanced the constitutive RNA and protein expressions of MMP-2 and MMP-9 in HTR8SVneo cell lines. Also, OSM treatment increased significantly the enzymatic activity of MMP-2 on gelatin zymography. The effects OSM on enzymatic activity of MMP-9 was not significant. We found that OSM increased invasion activities of HTR8SVneo cells in time-dependent and dose-dependent manners. This study suggests that OSM enhances invasion activities of extravillous trophoblasts during the first trimester through the increased enzyme activity of gelatinases, especially MMP-2.