Wnt pathway is involved in breast cancer (BC) progression. Our aim was to evaluate the expression of some components of the Wnt pathway (β-catenin, FZD4, LRP5, LRP6 and TCF1) in order to detect potential associations with NHERF1 protein. In addition, we assessed their impact on patients’clinical outcome. We evaluated 220 primary BC samples by immunohistochemistry (IHC) and protein localization by immunofluorescence. We found a significant correlation between NHERF1 and FZD4, LRP5, LRP6 and TCF1. Univariate analysis showed that β-catenin (p<0.0001), FZD4 (p=0.0001), LRP5, LRP6 and TCF1 over-expression (p<0.0001 respectively) was related to poor disease free survival (DFS). A Kaplan-Meier analysis confirmed univariate data and showed a poor DFS for cNHERF1+/FZD4+ (p=0.0007), cNHERF1+/LRP5+ (p=0.0002), cNHERF1+/LRP6+ (p<0.0001) and cNHERF1+/TCF1+ phenotypes (p=0.0034). In multivariate analysis, TCF1 and β-catenin expression were independent prognostic variable of worse DFS (p=0.009 and p=0.027, respectively). In conclusion, we found that β-catenin, FZD4, LRP5, LRP6 and TCF1 overexpression was associated to poor prognosis. Furthermore, we first identified TCF1 as independent prognostic factor of poor outcome, indicating it as a new potential biomarker for BC patients management. In addition, Wnt pathway proteins expression, both alone and in association with NHERF1, suggests original associations of biological significance for new studies.

To maintain an optimal body content of phosphorus throughout postnatal life, variable phosphate absorption from food must be finely matched with urinary excretion. This amazing feat is accomplished through synchronised phosphate transport by myriads of ciliated cells lining the renal proximal tubules. These respond in real time to changes in the phosphate and composition of the renal filtrate, and to hormonal instructions. How they do this has stimulated decades of research. New analytical techniques, coupled with incredible advances in computer technology, have opened new avenues for investigation at a sub-cellular level. There has been a surge of research into different aspects of the process. These have verified long held beliefs and are also dramatically extending our vision of the intense, integrated, intracellular activity which mediates phosphate absorption. Already, some have indicated new approaches for pharmacological intervention to regulate phosphate in common conditions, including chronic renal failure and osteoporosis, as well as rare inherited biochemical disorders. It is a rapidly evolving field. The aim here is to provide an overview of our current knowledge, to show where it is leading, and where there are uncertainties. Hopefully this will raise questions and stimulate new ideas for further research.