Trastuzumab had been widely used in clinical trials, which showed an improved therapeutic effect in clinical treatment of breast cancer patients.7,25 Anti-tumor activity of Trastuzumab was mainly based on two ways: Firstly, to combine with targeted proteins (HER-2) of tumor cell, inhibiting cell signaling transduction in the cancer cells26,27; second, to activate immune system, regulating immune mechanism to kill tumor cells.28,29 Fewer adverse reactions were found in trastuzumab immunotherapy, the effect of combined chemotherapy or radiotherapy was better in clinical treatment. This evidence concerns the gene ERBB2 and cancer.