Intracellular FGF-2 promotes differentiation in T-47D breast cancer cells

To test the implicated role of basic fibroblast growth factor (bFGF; FGF-S) in promoting differentiation in breast cancer, we enforced the expression of FGF-2 in T-47D breast cancer cells. Expression of FGF-S conferred an ove rall less malignant phenotype to T-47D cells as revealed by their reduced p roliferative response, impaired capacity for anchorage-independent growth, and invasion through Matrigel. To understand one candidate mechanism for th e intracellular FGF-2-mediated anti-invasive effect, we examined the effect of FGF-2 on T-47D cell motility. Addition of recombinant FGF-2 to the grow th medium markedly enhanced cell motility while constitutive expression of intracellular FGF-2 significantly inhibited the migratory potential of T-47 D cells in a dominant manner. FGF-2-expressing T-47D cells also formed rela tively defined branching structures in Matrigel matrices, a characteristic phenotype of differentiation in breast cancer cells. These data suggest a p otential role for FGF-2 in promoting functional differentiation of breast e pithelial cells. (C) 2000 Academic Press.