Objective To explore the possible mechanism of Modified Shengma Biejia Decoction（升麻鳖甲汤加减方） in treating acute myeloid leukemia. Methods The MTT method was used to observe the effects of 0

2

4

6

8

and 10 mg/ml of Modified Shengma Biejia Decoction on the inhibition rate of cell proliferation of HL-60 cells at 24 h

48 h

and 72 h. Take 5 × 10

5

/ml HL-60 cells in logarithmic growth phase and put into 6-well culture plates at a volume of 2 ml per well. Add the screened concentration of Modified Shengma Biejia Decoction of the high

medium

and low dose groups

and make the control group to add the same volume of complete medium. After continuing to screen the best experimental time

cells of each group were collected. Heochest 33258 staining and flow cytometry were used to observe the apoptosis rate of each group. Cell cycle distribution

mitochondrial membrane potential

and apoptosis-related proteins cysteine aspartase 3（caspase-3）

cysteine caspase-8（caspase-8）

cysteine caspase-9（cysteine-9）

polyphosphate adenosine ribose polymerase（PARP） expression

MAPK signaling pathway-related protein p38 Mitogen-activated protein kinase（p38 MAPK）

extracellular signal-regulated kinase（ERK）

and c-Jun amino-terminal kinase（JNK） protein expression were detected. Results The optimal effect time was 24 h after screening. The intervention concentrations of the low

medium and high dose groups of Modified Shengma Biejia Decoction were 4

6

and 8 mg/ml

respectively. The different dosage groups of Modified Shengma Biejia Decoction can inhibit the proliferation of HL-60 in human acute myeloid leukemia cells to varying degrees（P

<

0.05）. The results of Heochest 33258 staining and Annexin V/PI showed that all dose groups of Modified Shengma Biejia Decoction can increase the apoptosis rate and increase the mitochondrial membrane potential in a concentration-dependent manner（P

<

0.05）; the different dosage groups of Modified Shengma Biejia Decoction inhibite the expression of apoptosis-related proteins and the levels of MAPK signaling pathway-related proteins in a concentration-dependent manner（P

<

0.05）. Conclusion The Modified Shengma Biejia Decoction can inhibit the proliferation of HL-60 cells by blocking the cell cycle

inducing the loss of mitochondrial membrane potential

and inducing apoptosis

which may be related to the regulation of MAPK signaling pathway.