Elevated STAT3 phosphorylation was probably due to the previously described upregulation of JAK3 expression in sorafenib-resistant AML.34 Thus, we suggest that the activation of the PI3K/mTOR pathway leads to aberrant expression of survival proteins that further contributes resistance to multiple FLT3 inhibitors in MV4-11- and MOLM-13-resistant cell lines. Here, JAK3 is linked to acute myeloid leukemia.