Objective: To observe the growth inhibition effect of the single clone antibody of epidermal growth factor receptor (EGFR) Cetuximab combined with Paclitaxel (PTX) on human breast cancer cell line MCF-7.Methods: The experiment involved four groups: control group

Cetuximab group

PTX group and combination group. The inhibitory rates of Cetuximab

PTX and different combinations of Cetuximab and PTX on MCF-7 cells were examined by MTT assay and the apoptosis rate and cell cycle distribution were analyzed by flow cytometry. The immunofluorescence and RT-PCR were used to evaluate the EGFR protein and mRNA expression in control group and PTX group. Results:PTX can exert inhibitory effect on MCF-7 cells in a dose dependent manner based on the results from MTT assay. MTT assay showed that different combination schemes exerted different inhibitory effects; the synergistic effect was seen in the scheme of MCF-7 cells first treated with PTX and then Cetuximab. The apoptosis rate of the other three groups was increased compared with that of control group and the effect was more evident in combination group than in single agent groups (P<0.05).The EGFR protein and mRNA expressions reduced in PTX group compared with those in control group (P<0.05).Conclusion：Human breast cancer cell line MCF-7 was sensitive to PTX and PTX can exert inhibitory effect on MCF-7 cells in a dose dependent manner. The combination of Cetuximab and PTX can increase the apoptosis and decrease the proliferation of breast cancer cell line MCF-7 with a synergistic action.