MX1 and leukemia: Furthermore, co-culture of PKCα-KR cells revealed a significant decrease in the GFP+CD19+ cell number and reduced proliferation of Mx1-Raptor cKO CLL-like cells (and not Mx1-Raptor control cells) upon IFNβ treatment (Fig. 2G–I), supporting the role of mTORC1 in promoting leukemia propagation [13].