Expression of TGF-β1 and the mechanism of invasiveness and metastasis induced by TGF-β1 in breast cancer

Objective To investigate the expression of MMP-2,TIMP-2,TGF-β1 and TGF-βRI and the relationship among them in breast cancer.Methods The protein expression of MMP-2,TIMP-2,TGF-β1 and TGF-β1R1 was detected on tissue chips by S-P immunohistochemical staining in 160 cases of breast carcinoma.Results The positive rates of TGF-β1,TGF-β1 mRNA,MMP-2,MMP-9,TIMP-1 and TIMP-2 expression were 73.7%,56.2%,96.9%,95.0%,87.5% and 89.4%,respectively.Axillary lymph node metastasis and TNM staging(P ＜0.01 and P ＜0.01,respectively)were positively correlated to the expression of TGF-β1.Relase-free survival of TGF-β1 positive group was lower than that of TGF-β1 negative group(P = 0.023).The expression of M MP-2 or M M P-9 was positively correlated to that of TGF-β1 (r=0.170,P＜0.05;r =0.221,P＜0.01)and was negatively correlated to that of TGF-β1 mRNA(r =-0.126,P ＞0.05;r = 0.019,P ＞ 0.05).Conclusion The expression of TGF-β1 may be closely correlated with the invasion and metastasis of breast cancer.TGF-β1-induced invasiveness and metastasis of breast cancer cells are mediated by MMP-2 and MMP-9.