KDM2b/JHDM1b, an H3K36me2-specific demethylase, is required for initiation and maintenance of acute myeloid leukemia

The histone H3 lysine 36 dimethyl–specific demethylase KDM2b/JHDM1b, which is highly expressed in various human leukemias, was previously found to be important in regulating cell proliferation and cellular senescence. However, its functions in leukemia development and maintenance are unclear. Here, we demonstrate that ectopic expression of Kdm2b/Jhdm1b is sufficient to transform hematopoietic progenitors. Conversely, depletion of Kdm2b/Jhdm1b in hematopoietic progenitors significantly impairs Hoxa9/Meis1-induced leukemic transformation. In leukemic stem cells, knockdown of Kdm2b/Jhdm1b impairs their self-renewing capability in vitro and in vivo. The functions of Kdm2b/Jhdm1b are mediated by its silencing of p15Ink4b expression through active demethylation of histone H3 lysine 36 dimethyl. Thus, our study suggests that Kdm2b/Jhdm1b functions as an oncogene and plays a critical role in leukemia development and maintenance.