OBJECTIVETo explore the clinical value of PKC412 (midostaurin) in treatment of AML patients with FLT3.

METHODSThe bone marrow or peripheral blood were collected and heparinized from 21 newly diagnosed FLT3AML patients, then the mononuclear cells from bone marrow or peripheral blood were isolated by density-gradient method. The sensitivity of leukemia cells to PKC412 of 8 concentration in vitro was detected by ATP-bioluminescence-tumor chemosensitivity assay (ATP-TCA), and the relationship among sensitivity results in vitro, risk stratification and therapeutic efficacy was analyzed.

RESULTSThe leukemia cells of 21 patients with AML displayed different sensitivities to PKC412 in vitro. The rate of sensitivity in vitro was 42.9%, and sensitive concentration in vitro were between 1 µmol/L and 5 µmol/L. There was no significant relationship between risk stratification and sensitivity results of PKC412 in vitro. There was also no significant relationship between clinical efficacy and sensitivity results of PKC412 in vitro. The survival of patients in low-risk and intermediate-risk groups was better than that of patients in high-risk groups (P=0.015).

CONCLUSIONPKC412 can be one of the effective therapeutic method for AML patients without FLT3 mutation. The sensitivity of leukemia cells to PKC412 may become a prognostic marker for evaluating clinical efficacy of PKC412, which is independent of other factors.