Basic fibroblast growth factor, albumin, and transferrin purified from rat rhodamine fibrosarcoma tissue are all essential for growth of primary tumor cells from the same tissue in serum-free medium

Distribution of fibroblast growth factors in cultured tumor cells and their transplants

The distributions of acidic fibroblast growth factor (aFGF) and basic FGF (bFGF) in extracts of various cultured mammalian cells were determined from their elution profiles on heparin-affinity chromatography, and assay of activity as ability to stimulate DNA synthesis in BALB/c3T3 cells. Only aFGF was found in extracts of mouse melanoma B 16 cell and rat Morris hepatoma cell (MH1C1) lines. Other tumor cell lines established from solid tumors and some normal cells contained bFGF as a main component, but blood tumor cell lines contained no aFGF or bFGF. The FGFs in extracts of solid tumor tissues derived by transplantations of these cultured tumor cells and various normal tissues of mice were also examined. Tumors formed by all cell lines, regardless of whether they produced aFGF, bFGF, or neither, contained bFGF that was probably derived from host cells including capillary endothelial cells, in addition to the tumor-derived aFGF or bFGF, if produced. The content of bFGF, possibly derived from the host, in these tumor tissues was comparable to those of various mouse organs other than thymus, lung, spleen, and testis, which have higher bFGF contents. Tumor tissues derived from cultured cells producing bFGF had relatively higher bFGF contents. Like bFGF, aFGF was distributed almost ubiquitously in normal mouse tissues.

Production of basic fibroblast growth factor-like factor by cultured human cholangiocellular carcinoma cells

An extract of cultured human cholangiocellular carcinoma cells (HuCC-T1) was found to contain high mitogenic activity for BALB/c3T3 cells. The growth factor eliciting most of the mitogenic activity was purified and concluded to be identical with basic fibroblast growth factor (bFGF)-like factor on the basis of its molecular weight and heparin-Sepharose elution profile, and the results of immunoblotting and radioimmunoassay. HuCC-T1 cells also secreted bFGF-like factor into serum-free medium. A combination of insulin and transferrin or bovine serum albumin stimulated the growth of HuCC-T1 cells in serum-free medium. However, bFGF did not stimulate their growth in the presence and absence of these supplements. Neutralizing monoclonal antibody against bFGF did not inhibit growth. These results indicate that bFGF-like factor is not a growth factor for this cell line.