[Suramin inhibits the proliferation and stimulates the differentiation of tumoral cell lines HT29-D4 and C6].

Suramin is an anti-helminthic drug that has been shown to antagonize the effects of a variety of growth factors including EGF, PDGF and TGF beta. When added to the culture medium, suramin inhibited the proliferation of both human colonic adenocarcinoma cells HT29-D4 and rat glioma cells C6. Suramin also induced the differentiation of both cell lines: appearance of cellular extensions for C6 cells, enterocyte-like epithelial differentiation for HT29-D4-cells. In the latter case, suramin probably acts at the level of glucose metabolism, which is likely to be modulated by autocrine growth factors. The permanent secretion of such factors probably stimulates HT29-D4 proliferation and simultaneously inhibits their differentiation. It is hypothesized that interfering with this autocrine loop, suramin allows HT29-D4 cells to differentiate.