Objective: Observe the effect of extractive from Periplaneta americana（CⅡ-3） on immune and on inhibitory tumor action in S180-bearing mice.Method: S180 sarcoma was implanted into right-fore oxter

then randomly divided into normal group

model group

cyclophosphamide group（30 mg·kg-1

ip quaque die alterna）

CⅡ-3 high dosage group

medium dosage group and low dosage group（200

100

50 mg·kg-1

ig）

the S180-bearing mice in every group were received corresponding treatment for 10 days.Tumor growth of the mice was observed

immune organs were weighted to calculate the organ index and ELISA was used to test the concentration of vascular tumor necrosis factor-α（TNF-α） in serum.Results: CⅡ-3 inhibited the growth of S180 sarcoma significantly

200

100

50 mg·kg-1 dosages inhibited the tumor weight by 58.22%

45.66%

35.37%.CⅡ-3 had protective function on immune

the liver indexs in high dosage group

medium dosage group and low dosage group were 53.54

54.15 59.53 mg·g-1 respectively

spleen indexs were 3.60

4.44

5.18 mg·g-1 respectively and thymic indexs were 2.45

2.00

2.30 mg·g-1 respectively.And it dramatically increased the concentration of TNF-α in serum

the concentrations of TNF-α of three groups were 324.92

304.81

278.84 ng·L-1.Conclusion:These results suggest that the CⅡ-3 can obviously inhibit the growth of tumor in S180-bearing mice and toxic effects on immune organs have not fpund

one of anti-tumor effects by CⅡ-3 may be mediated by increasing concentrations of TNF-α in serum.