Mouse Podxl (Podocalyxin) ELISA Kit

The zebrafish pronephros provides an excellent in vivo system to study the mechanisms of vertebrate nephron development. When and how renal progenitors in the zebrafish embryo undergo tubulogenesis to form nephrons is poorly understood, but is known to involve a mesenchymal to epithelial transition (MET) and the acquisition of polarity. Here, we determined the precise timing of these events in pronephros tubulogenesis. As the ternary polarity complex is an essential regulator of epithelial cell polarity across tissues, we performed gene knockdown studies to assess the roles of the related factors atypical protein kinase C iota and zeta (prkc iota, prkc zeta). We found that prkcz and prkc zeta serve partially redundant functions to establish pronephros tubule epithelium polarity. Further, the loss of prim or the combined knockdown of prkc iota/zeta disrupted proximal tubule morphogenesis and podocyte migration due to cardiac defects that prevented normal fluid flow to the kidney. Surprisingly, tubule cells in prkc iota/zeta morphants displayed ectopic expression of the transcription factor pax2 alpha and the podocyte-associated genes wtl alpha, wtlb, and podxl, suggesting that prkc iota/zeta are needed to maintain renal epithelial identity. Knockdown of genes essential for cardiac contractility and vascular flow to the kidney, such as tnnt2 alpha, or elimination of pronephros fluid output through knockdown of the intraflagellar transport gene ift88, was not associated with ectopic pronephros gene expression, thus suggesting a unique role for prkc iota/zeta in maintaining tubule epithelial identity separate from the consequence of disruptions to renal fluid flow. Interestingly, knockdown of pax2 alpha, but not wtla, was sufficient to rescue ectopic tubule gene expression in prkc iota/zeta morphants. These data suggest a model in which the redundant activities of prkc iota and prkc zeta are essential to establish tubule epithelial polarity and also serve to maintain proper epithelial cell type identity in the tubule by inhibiting pax2 alpha expression. These studies provide a valuable foundation for further analysis of MET during nephrogenesis, and have implications for understanding the pathways that affect nephron epithelial cells during kidney disease and regeneration. (C) 2014 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-SA license

Background: Urothelial bladder cancer (UBC) is a disease that often is discovered when the tumour is non-muscle invasive, i.e. in Ta or T1 stage. Some patients will progress into muscle-invasive disease, a potentially deadly condition. Although there are some prognostic models, the need for prognostic and predictive biomarkers is considerate and urgent. Membranous expression of podocalyxin-like protein 1 (PODXL) and low expression of the RNA-binding motif 3 (RBM3) has previously been shown to be associated with an aggressive tumour phenotype and poor prognosis in several forms of cancer, including UBC. In this study, we sought to validate the prognostic impact of PODXL and RBM3 in an independent cohort of UBC. Methods: Using tissue microarrays and immunohistochemistry, PODXL and RBM3 expression was evaluated in 272 incident UBC cases from the prospective, population-based cohort study Malmo Diet and Cancer. Kaplan-Meier analysis and Cox proportional hazards modelling were used to evaluate the prognostic impact of these markers on 5-year overall survival (OS). Results: In line with previous studies, both membranous PODXL expression and low RBM3 expression was significantly associated with disadvantageous clinicopathological features. Membranous PODXL expression was significantly associated with a reduced 5-year overall survival in the entire cohort (univariable HR 3.28; 95% CI 1.89-5.69), but this association did not remain significant in multivariable analysis. In T1 tumours, PODXL was significantly associated with reduced survival in univariable analysis (HR = 2.83; 95% CI 1.04-7.72) and borderline significant in multivariable analysis (HR = 2.60; 95% CI 0.91-7.39). Low RBM3 expression was an independent predictor of a reduced survival in the entire cohort (univariable HR 3.19; 95% CI 2.02-5.04, and multivariable HR 1.85; 95% CI 1.11-3.09), and in T1 tumours (univariable HR 2.64; 95% CI 1.11-6.27, and multivariable HR 2.63; 95% CI 1.01-6.84). Conclusions: A link between membranous PODXL expression and clinically more aggressive tumours was further confirmed, but PODXL expression was not an independent prognostic biomarker in this study. Low RBM3 expression was validated as an independent factor of poor prognosis in UBC, including T1 disease. These findings suggest that these biomarkers could be useful in stratifying patients with non-muscle invasive disease for more aggressive first line treatment.