OBJECTIVETo study the action mechanism of Yiqi Yangyin Recipe (YYR) in treating leukemia by observing the effects of YYR and its different assembling, energy supporting part (P1) and evil dispelling part (P2) on expressions of Flt3 and N-ras gene in acute myeloid leukemic (AML) cells.

METHODSThe mononuclear cells collected from bone marrow of 60 AML patients were assigned to four groups: the blank was untreated for control and the three tested groups were treated with YYR, P1 and P2, respectively. The effects on Flt3 and N-ras gene expressions and FLT3 protein expression were observed by RT-PCR and Western bloting.

RESULTSRT-PCR test showed the expression of Flt3 in the control, YYR, P1 and P2, group was 90.78% +/- 6.92%, 38.18% +/- 4.50%, 65.57% +/- 5.55% and 61.35% +/- 6.39%, respectively; and that of N-ras in them 93.28% +/- 5.54%, 34.38% +/- 6.69%, 59.42% +/- 7.35% and 65.28% +/- 7.64%, respectively, both showed significant difference as compared the data in the tested groups with those in the control group (P < 0.05). Western bloting test showed the FLT3 protein gray value in the four groups was 0.8127 +/- 0.0284, 0.4265 +/- 0.0353, 0.5396 +/- 0.0274 and 0.5473 +/- 0.0282, respectively, also showed significant difference between the control and the tested groups (P < 0.01).

CONCLUSIONYYR can inhibit the colonic proliferation of AML cells, decrease the expressions of FLT3 and N-ras in cells, therefore shows a therapeutic effect on AML.