Objective: To investigate effect of Tonglian decoction(T) on proliferation of esophageal carcinoma cell line Eca109 through determination of cell morphology and cell cycle

and to discuss inhibition mechanism of the prescription on esophageal carcinoma. Method: Human esophageal carcinoma cell line Eca109 cultured in vitro were treated with T and its separated formulae

including clearing-heat-and-detoxification formula (Q)

activating-blood-and-promoting-Qi formula (H) and nourishing-Yin-and-blood formula (Z). Cell proliferation was assayed by MTT

cells morphology was observed with microscope and cell cycle was measured with Flow Cyto Meter (FCM). Result: Dose for 50 percent cells inhibition rates (IC50) of T

Q and H was 386

771

729 mg·L-1

respectively. T

Q and H inhibit cell proliferation predominantly

rate of G1 phase of cell cycle reached to 69.43%

60.84%

61.90%

respectively. Cells number in S phase treated with T

Q

and H had significant difference with controlled group (P<0.05)

and T had the best effect. But Z has little inhibition power

having no difference with controlled group. Conclusion: T can be used to regulate Eca109 carcinoma cell proliferation with inhibiting cells S phase. During whole process

3 separated formulae cooperate with each other to insure effect of T.