Expression and function of autocrine motility factor receptor in human choriocarcinoma

Our purpose was to determine whether human choriocarcinoma cells express autocrine motility factor receptor (AMF-R) and to study its function in this tumor system.

The expression and localization of AMF-R were compared in choriocarcinoma and normal placental trophoblasts using both cell lines and tissue sections. In addition, migratory properties of choriocarcinoma cells and normal placental cells was determined.

Using immunofluorescence and immunoperoxidase staining, we have detected the expression of AMF-R in choriocarcinoma cells with receptor clustering on the cell surface, while term placenta cells expressed AMF-R less intensely with no receptor clustering. In choriocarcinoma tissues, AMF-R was strongly expressed in malignant cytotrophoblasts cells while adjacent normal villous trophoblast cells and necrotic regions were weakly or negatively stained. Choriocarcinoma cells responded to AMF-R stimulation with increased cell motility, while term placental cells were unresponsive.

Human choriocarcinoma cells express functional cell surface AMF-R in vitro and in choriocarcinoma tissue suggesting that this receptor may play an important role in cancer cell motility.