Prevalence of protein C receptor (PROCR) is associated with inferior clinical outcome in Breast invasive ductal carcinoma.

Recently, PROCR is reported to play an important role in cell growth, apoptosis, proliferation and tumor relapse. Some researchers thought that PROCR cells had cancer stem cell ability, which might contribute to progressive behavior in breast cancer. Our study was to assess the expression of PROCR in invasive ductal carcinoma tissues with their prognostic implications. We enrolled formalin fixed paraffin-embedded tumor tissues of 271 patients diagnosed as invasive ductal breast cancer with clinical stage II or III into our study. Immunohistochemistry staining was performed on all the tissue microarray slides, and result were interpreted by two pathologists with blinded method. We analyzed PROCR expression levels with the clinical characteristics as well as their prognostic values. PROCR expression detected in the cell was interpreted. Chi-square test showed us its positive expression had a close association with distant metastases (p=0.035). Univariate survival analysis indicated that prevalence of PROCR expression in the invasive ductal breast cancer was significantly related with decreased disease-free survival (p=0.010) and overall survival (p=0.008). In multivariate survival by Cox proportional hazard model, positive expression group for PROCR was found to have shorter DFS [p=0.028, hazard ratio (95% CI): 1.183(1.069-3.140)]. Our findings suggested that breast cancer patients with expression of PROCR is more prone to suffer from distant metastasis and bad clinical outcomes.