Background E-cadherin,beta-catenin,cathepsin D,matrix metalloproteinase(MMP)-2,MMP-9,tissue inhibitors ofmetalloproteinase(TIMP)-1 and TIMP-2 are all invasion-related proteins.The expression patterns of these proteins ininvasive ductal breast carcinomas,and their associations with known clinicopathological parameters,tumor recurrenceand expressions of estrogen receptor(ER),progesterone receptor(PR),PS2 and c-erbB2 were not well studied inChinese patients.Methods In a set of 94 invasive ductal breast carcinomas,protein expressions of these molecular markers wereinvestigated by immunohistochemistry,and their associations with known clinicopathological parameters,tumorrecurrence and expressions of ER,PR,PS2 and c-erbB2 were also examined.In addition,the interrelationship betweenthe expressions of these proteins were studied.Results Preserved membrane E-cadherin expression was associated with late tumor stage and tumor recurrence,whereas the reduced junctional beta-catenin associated with positive lymph node status and c-erbB2 overexpression.Positive staining of cathepsin D in tumor stromal cells displayed a significant association with late tumor stage.Highexpression of MMP-2 in cancer cells was associated with large tumor size and PR positive expression.TIMP-2expression was positively associated with tumor recurrence.In addition,inter-relationship between the expressions ofthese biomarkers was also assessed.Cathepsin D staining in cancer cells was inversely correlated with its staining instromal cells,and also inversely correlated with MMP-2 staining in tumor stromal cells.MMP-2 expression in stromal cellsdisplayed an inverse correlation with TIMP-2 expression.MMP-9 expression displayed parallel associations with TIMP-1and TIMP-2 expression.Conclusion Evaluation of E-cadherin,beta-catenin,cathepsin D,MMP-2 and TIMP-2 expression may be of some helpin more accurately predicting the prognosis of invasive ductal breast carcinomas. Background E-cadherin, beta-catenin, cathepsin D, matrix metalloproteinase (MMP) -2, MMP-9, tissue inhibitors of metalloproteinase (TIMP) -1 and TIMP-2 are all invasion-related proteins. These expression patterns of these proteins in invasive ductal breast carcinomas, and their associations with known clinicopathological parameters, tumor recurrence and expressions of estrogen receptor (ER), progesterone receptor (PR), PS2 and c-erbB2 were not well studied in Chinese patients. Methods In a set of 94 invasive ductal breast carcinomas , protein expressions of these molecular markers were investigated by immunohistochemistry, and their associations with known clinicopathological parameters, tumor recurrence and expressions of ER, PR, PS2 and c-erbB2 were also examined.In addition, the interrelationship betweenthe expressions of these proteins were studied.Results Preserved membrane E-cadherin expression was associated with late tumor stage and tumor recurrence, whereas the reduced junctional beta-catenin associated with positive lymph node status and c-erbB2 overexpression. Positive staining of cathepsin D in tumor stromal cells displayed a significant association with late tumor stage. Hexhexpression of MMP-2 in cancer cells was associated with large tumor size and PR positive expression. TMP-2 expression was positively associated with tumor recurrence. In addition, inter-relationship between the expressions of the biomarkers was also assessed. Cartein D staining in cancer cells was inversely correlated with its staining instromal cells, and also inversely correlated with MMP-2 staining in tumor stromal cells . MMP-2 expression in stromal cells displayed an inverse correlation with TIMP-2 expression. MMP-9 expression displayed parallel associations with TIMP-1 and TIMP-2 expression. Conlusion Evaluation of E-cadherin, beta-catenin, cathepsin D, and TIMP-2 expression may be of some helpin more accurately predicting the prognosis of invasive ductal breast carcinomas.