Expressions of DLL4,COX-2 and MMP-2 in breast cancer tissues and its significance

Objective To study the expressions of DLL4(delta-like ligand 4),COX-2(Cyclooxygenase-2) and MMP-2(matrix metalloproteinase-2) in different molecular subtypes of breast cancer and analyze their correlation.Methods The expressions of DLL4,COX-2 and MMP-2 were determined by SP immunohistochemistry in 100 cases of breast carcinoma(41 luminal A,18 lumianl B,22 HER-2 over-expression and 19 basal-like subtypes) and 40 cases of adjacent normal breast tissues.Then the correlation of DLL4,COX-2 and MMP-2 expression with lymph node metastasis was analyzed.Results The positive expression rates of DLL4,COX-2 and MMP-2 in breast cancer were 73.0%,81.0% and 93.0%,significantly higher than those in adjacent normal breast tissues(P0.05).The positive rates of DLL4,COX-2 and MMP-2 were 95.5%,100.0% and 100.0% in HER-2 over-expression type,and 89.5%,94.7% and 100.0% in basal-like subtype.They were significantly higher than those in luminal A and luminal B subtypes(P0.05).The expression of DLL4,COX-2 and MMP-2 in lymph node metastasis group were 88.7%,92.5% and 96.2% respectively,higher than those without lymph node metastasis group(P0.05).Positive correlation could be found between DLL4 and COX-2,MMP-2 expression(r=0.215,P0.05;r=0.435,P0.05).Conclusion DLL4,COX-2 and MMP-2 are highly expressed in HER-2 over-expression and basal-like subtypes of breast cancer.These results suggest that they might be important factors in breast carcinogenesis,development and metastasis.These proteins are indicators of metastasis of breast cancer.