MTOR and myelofibrosis: This nicely parallels the situation in chronic myeloid cancers, such as myelofibrosis where recently two independent reports showed that in myelofibrosis and in MPN models, the combination of JAK2 inhibitors and PI3K (pan type I) inhibitors, such as ZSTK424, GDC0941 and NVP-BEZ235 (also an mTOR inhibitor), synergize to prevent cytokine-independent proliferation, which is characteristic of MPNs [123, 124].