Effects of STAT3 antisense RNA on IL-6-induced differentiation and growth arrest of M1 leukemia cells

To investigate the biological roles of STAT3 in the regulation of growth an d differentiation of leukemia cells, we modified a murine myeloid leukemia cell line M1 with STAT3 antisense RNA. The effects of STAT3 antisense RNA o n the growth arrest and terminal differentiation of M1 cells induced by int erleukin 6 (IL-6) were determined. It was found that STAT3 antisense RNA bl ocked the activation of STAT3, and reduced the growth arrest and terminal d ifferentiation of IL-6-induced M1 leukemia cells. These results indicate th at STAT3 activation is a necessary process for IL-6-induced growth arrest o f M1 cells and for the differentiation of M1 cells into macrophage.