Recombinant tumor necrosis factor alpha and interleukin 1 alpha increase expression of c-abl protooncogene mRNA in cultured human marrow stromal cells.

Analysis of protooncogene RNA expression in marrow stromal cells from long-term marrow culture demonstrated high levels of c-abl 5-, 6-, and 7-kilobase (kb) RNA transcripts. In experiments on three independently derived simian virus 40-transformed marrow stromal cell lines, the expression of these c-abl transcripts was further increased in response to recombinant tumor necrosis factor alpha (1000 units/ml) and interleukin 1 alpha (10 units/ml). Although lymphocyte-conditioned medium predominantly up-regulated the 5-kb transcript, interleukin 1 alpha primarily affected the 6-kb transcript. The up-regulation of the 5-kb c-abl message correlated with up-regulation of the granulocyte/macrophage colony-stimulating factor transcript and down-regulation of procollagen I transcripts in transformed cells. These data suggest that c-abl plays roles in the regulation of extracellular matrix expression and in the regulation of hematopoietic growth factors by stromal cells.