TRANSFECTED MCF-7 CELLS AS A MODEL FOR BREAST-CANCER PROGRESSION

The MCF-7 human breast carcinoma cell line has been used as a recipien t for eukaryotic plasmid expression vectors to determine the effects o f growth factor and growth factor receptor overexpression on the estro gen-dependent, antiestrogen sensitive and poorly metastatic phenotypes exhibited by this line. Overexpression of some members of the erbB fa mily of ligands and receptors were found to have some effects on these phenotypes. However, only when two members of the fibroblast growth f actor family, FGF-1 and FGF-4, were overexpressed was progressive in v ivo growth observed is either ovariectomized nude mice without estroge n supplementation or in mice that received tamoxifen treatment. FGF tr ansfected cells also exhibited an increased ability to form micrometas tases. The implications of these results with regard to the possible r ole of the paracrine and autocrine effects of angiogenic growth factor production in breast cancer progression are discussed.