Objective To research the effect of Changweiqing Granules（TCM formula to clean up the stomach）containing serum combined with Carboplatin on the proliferation and apoptosis of resistant human colon cancer cells. Methods The sensitive human colon cancer cells HCT116 and resistant human colon cancer cells HCT116/L-OHP were intervened by 2.5%

5.0%

10.0% and 20.0% Changweiqing containing serum.The combination concentration of Changweiqing containing serum was selected.HCT116 and HCT116/L-OHP were intervened by different concentrations of Carboplatin.The combination time of Carboplatin was determined.The MTT assay was used to detect HCT116/L-OHP cell growth inhibited by Changweiqing containing serum combined with Carboplatin.The cell cycle distribution was analyzed with flow cytometry and propidium iodide（PI）staining.The apoptosis was detected with Annexin V-FITC kit.Results The resistance index of HCT116/L-OHP cells to Carboplatin was 3.17.The half inhibitory concentration （IC50） of Carboplatin was （325.97±29.26）mg/L.There were 6% Changweiqing containing serum selected to act on HCT116/L-OHP cells with Carboplatin for 48 hours.The IC50 of Changweiqing combined with Carboplatin was （68.64±5.74）mg/L and the resistance index was 4.75.The apoptosis rates in the combination group and Carboplatin group were higher than that in the blank group and the apoptosis rate in the combination group was higher than that in the Carboplatin group（P<0.05）.There were significant differences between groups in the cell cycle distribution of G1

G2 and S phase （P<0.05）.Conclusion Changweiqing Granules containing serum can effectively reverse the resistance of resistant human colon cancer cells HCT116/L-OHP to Carboplatin

induce the apoptosis of HCT116/L-OHP

increase the distribution rate of cells in G2 phase and decreased the distribution rate of cells in S phase.