The prognostic value of stromal and epithelial periostin expression in human breast cancer: correlation with clinical pathological features and mortality outcome

摘要

Background PN is a secreted cell adhesion protein critical for carcinogenesis. In breast cancer, it is overexpressed compared to normal breast, and a few reports suggest that it has a potential role as a prognostic marker. Methods Tumour samples obtained at the time of mastectomy from 200 women followed for a median time of 18.7?years (range 0.5–29.5?years) were investigated through IHC with a polyclonal anti-PN antibody using tissue microarrays. Epithelial and stromal PN expression were scored independently according to the percentage of coloured cells; the 60th percentile of PN epithelial expression, corresponding to 1?%, and the median value of PN stromal expression, corresponding to 90?%, were used as arbitrary cut-offs. The relationships between epithelial and stromal PN expression and clinical-pathological features, tumour phenotype and the risk of mortality following surgery were analysed. Appropriate statistics, including the Fine and Gray competing risk proportional hazard regression model, were used. Results The expression of PN in tumour epithelial cells was significantly lower than that which was observed in stromal cells ( p Conclusions Although they require further validation through larger studies, our findings suggest that the patterns of expression of PN in both compartments can allow for the development of IHC “signatures” that maintain a strong independent predictive value of both all causes and, namely, of cancer-specific mortality.