Modulation by colony stimulating factors of human epithelial colon cancer cell apoptosis.

Colony stimulating factors (CSF) promote leukocyte survival by reducing apoptotic cell death. However, their effects on non-leukocyte cell types are unclear. Reduced apoptosis in colon epithelial cells is thought to contribute to the initiation of cancer. Here, we report diminished spontaneous apoptosis of human colon epithelial HT-29 cells in the presence of macrophage-CSF or granulocyte macrophage-CSF. Moreover, reduced apoptosis induced by sulindac sulfide was also observed with macrophage-CSF. Granulocyte-CSF failed to modify spontaneous or sulindac sulfide induced apoptosis. It seems, therefore, that the action of CSFs on apoptosis is not confined to haematopoietic cells but may be extended to stromal cells.