ABSTRACT
OBJECTIVES: To define the biology of the tumor-host cell interaction with regard to cellular kinetics and morphologic changes during cell-cell interaction in an in vitro model of trophoblastic neoplasia. METHODS: Using a coculture in vitro system of cytotrophoblasts and choriocarcinoma cells, we investigated the cellular kinetics and the morphologic changes in these interacting cells. A fully automatic time-lapse image system was used to record phase contrast images of the cocultured cells in a tissue culture chamber. To examine cytoskeletal structure, immunofluorescent-labeled antibodies against intermediate filaments were used. Slides were examined with a confocal laser scanning microscope and subjected to computed analysis. RESULTS: The choriocarcinoma cells attract normal cytotrophoblasts using what resembles pseudopodia to engulf the latter cells and thus form slow-growing colonies. In this process, new hybrid cells are formed, which can be differentiated from their original contributors by morphologic characteristics. CONCLUSION: This phenomenon supports our previous biochemical and molecular data on the role of cell-cell interaction in the complex process of cytotrophoblast transformation and the development of gestational trophoblastic neoplasia.
