Effect of tumor necrosis factor-alpha on a cell line transformed by a secreted form of human fibroblast growth factor-1 gene and on its parental cell line

In the present study we characterized the responses of the cell line HST-α, stably transformed by a secreted form of human fibroblast growth factor-1 (acidic FGF) gene, and its parental NIH 3T3 cell line to recombinant murine (rMu) TNF-α. Treatment of HST-α cells with rMu TNF-α can significantly reduce the number of foci formed in the in vitro transformation assay. In the presence of the RNA polymerase inhibitor actinomycin-D, the transformed HST-α cell is more susceptible to the cytotoxicity of rMu TNF-α than is its parental NIH 3T3 cell. The median lethal concentrations (LC50) of rMu TNF-α to HST-α cell and NIH 3T3 cell were 0.35 ng/ml and 4.56 ng/ml respectively. These results demonstrated that the introduction of a single oncogene or a growth factor gene to a cell can change the cellʹs response to cytokines.