Abstract: Objective To explore the relationship and clinical significance between the expressions of melatonin receptor（MT1） and CUE domaincontaining 2（CUEDC2） in breast cancer. Methods Western blotting and immunohistochemical method were performed to detect the expression of MT1 and CUEDC2 in 80 invasive ductal breast cancer， 30 intraductal breast cancer and 30 normal breast tissues. Results The positive expression rates of MT1 in invasive ductal breast cancer， intraductal breast cancer and normal breast tissue were 78.8％，60.0％ and 16.7％ with statistical significance（P＜0.05）. The positive expression rate of CUEDC2 in invasive ductal breast cancer and intraductal breast cancer tissue was 68.8％ and 53.3％, higher than 133％ in normal breast tissue（P＜0.05）. Western blotting showed expressions of MT1 and CUEDC2 in invasive ductal breast cancer were 0.542±0.078 and 0.461±0.057， significantly higher than those in normal breast tissue（P＜0.05）. The positive expressions of MT1 and CUEDC2 in invasive ductal breast carcinoma was correlated with axillary lymphnode metastasis（P=0.034，P=0.027） and histological grade（P=0.018，P=0.022），but not with age and tumor size of patients（P＞0.05）. Positive correlation was observed between the expression of MT1 and CUEDC2 in invasive ductal breast cancer（r=0.44，P＜0.05）.
ConclusionThe overexpression of MT1 and CUEDC2 is related with the occurrence，development and metastasis of breast carcinoma. The combined detection of their expression provides experimental evidence for finding the new intervention targets in the breast cancer gene therapy