The results showed that the average value of AGR2 in healthy control group was 2.93 ± 0.42 ng/ml (n = 56), that in breast cancer group was 5.62 ± 0.87 ng/ml (n = 118), and that in breast cancer metastasis group was 13.7 ± 3.2 ng/ml (n = 23). The gene discussed is AGR2; the disease is breast cancer.