INTERACTION OF BASIC FIBROBLAST GROWTH-FACTOR (FGF-2) WITH NONRESPONSIVE HELA-CELLS

Human HeLa adenocarcinoma cells did not respond to basic fibroblast growth factor (bFGF or FGF-2) but did bind the same amount of bFGF as responsive Chinese hamster lung fibroblasts (CCL 39). Heparitinase II treatment of HeLa and CCL 39 cells resulted in a decrease of bFGF binding by 96 and 57%, respectively, indicating that heparan sulfate molecules were involved in bFGF binding. On HeLa cells, bFGF bound to a single family of low-affinity sites. Cross-linking experiments of I-125-bFGF to HeLa cells yielded several labeled complexes. Cell-associated (125)-bFGF Was internalized in both cell types either by high-affinity receptors and heparitinase-sensitive sites in CCL 39 cells or by heparitinase-sensitive binding sites only in HeLa cells. The binding of bFGF to nonresponsive HeLa cells and its internalization via a family of heparitinase-sensitive binding sites might illustrate other functions of bFGF unrelated to cell proliferation. (C) 1994 Academic Press,Inc.